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1.
Braz. j. med. biol. res ; 56: e12546, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1505884

ABSTRACT

Intense stimulation of most living cells triggers the activation of immediate early genes, such as Fos and Jun families. These genes are important in cellular and biochemical processes, such as mitosis and cell death. The present study focused on determining the temporal expression pattern of Fos and Jun families in fibroblasts and neural stem cells of cerebellum, hippocampus, and subventricular zone (SVZ) of rats of different ages at 0, 0.5, 1, 3, and 6 h after stimulation with fibroblast growth factor (FGF)-2. In neonates, a similar expression pattern was observed in all cells analyzed, with lower expression in basal condition, peak expression at 0.5 h after stimulation, returning to baseline values between 1 and 3 h after stimulation. On the other hand, cells from adult animals only showed Fra1 and JunD expression after stimulation. In fibroblasts and hippocampus, Fra1 reached peak expression at 0.5 h after stimulation, while in the SVZ, peak level was observed at 6 h after stimulation. JunD in fibroblasts presented two peak expressions, at 0.5 and 6 h after stimulation. Between these periods, the expression observed was at a basal level. Nevertheless, JunD expression in SVZ and hippocampus was low and without significant changes after stimulation. Differences in mRNA expression in neonate and adult animals characterize the significant differences in neurogenesis and cell response to stimulation at different stages of development. Characterizing these differences might be important for the development of cell cultures, replacement therapy, and the understanding of the physiological response profile of different cell types.

2.
Braz. j. otorhinolaryngol. (Impr.) ; 87(3): 274-282, May-Jun. 2021. graf
Article in English | LILACS | ID: biblio-1285692

ABSTRACT

Abstract Introduction Postoperative dysphonia is mostly caused by vocal fold scarring, and careful management of vocal fold surgery has been reported to reduce the risk of scar formation. However, depending on the vocal fold injury, treatment of postoperative dysphonia can be challenging. Objective The goal of the current study was to develop a novel prophylactic regenerative approach for the treatment of injured vocal folds after surgery, using biodegradable gelatin hydrogel microspheres as a drug delivery system for basic fibroblast growth factor. Methods Videoendoscopic laryngeal surgery was performed to create vocal fold injury in 14 rabbits. Immediately following this procedure, biodegradable gelatin hydrogel microspheres with basic fibroblast growth factor were injected in the vocal fold. Two weeks after injection, larynges were excised for evaluation of vocal fold histology and mucosal movement. Results The presence of poor vibratory function was confirmed in the injured vocal folds. Histology and digital image analysis demonstrated that the injured vocal folds injected with gelatin hydrogel microspheres with basic fibroblast growth factor showed less scar formation, compared to the injured vocal folds injected with gelatin hydrogel microspheres only, or those without any injection. Conclusion A prophylactic injection of basic fibroblast growth factor -containing biodegradable gelatin hydrogel microspheres demonstrates a regenerative potential for injured vocal folds in a rabbit model.


Resumo Introdução A disfonia pós-operatória é causada principalmente por cicatrizes nas pregas vocais. Tem sido relatado que o manejo cuidadoso da cirurgia das pregas vocais reduz o risco de formação de cicatriz. No entanto, a depender da lesão da prega vocal, o tratamento da disfonia pós-operatória pode ser desafiador. Objetivo Desenvolver uma nova abordagem regenerativa profilática para o tratamento de pregas vocais lesionadas após a cirurgia, com microesferas biodegradáveis de hidrogel de gelatina como sistema de administração de medicamentos para o Fator Básico de Crescimento de Fibroblastos (bFGF). Método A cirurgia laríngea videoendoscópica foi feita para criar lesão nas pregas vocais em 14 coelhos. Imediatamente após esse procedimento, microesferas biodegradáveis de hidrogel de gelatina com bFGF foram injetadas na prega vocal. Duas semanas após a injeção, as laringes foram excisadas para avaliação da histologia das pregas vocais e do movimento da mucosa. Resultados A presença de função vibratória deficiente foi confirmada nas pregas vocais lesionadas. A histologia e a análise de imagem digital demonstraram que as pregas vocais lesionadas injetadas com microesferas de hidrogel de gelatina com bFGF apresentaram menor formação de cicatriz, em comparação com as pregas vocais lesionadas injetadas apenas com microesferas de hidrogel de gelatina ou aquelas sem injeção. Conclusão Uma injeção profilática de microesferas biodegradáveis de hidrogel de gelatina com bFGF demonstra um potencial regenerativo para pregas vocais lesionadas em um modelo de coelho.


Subject(s)
Animals , Vocal Cords/surgery , Gelatin , Rabbits , Fibroblast Growth Factor 2 , Hydrogels , Microspheres
3.
Braz. dent. j ; 32(1): 98-103, Jan.-Feb. 2021. graf
Article in English | LILACS, BBO | ID: biblio-1180724

ABSTRACT

Abstract Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (FGF-2) have the ability to increase vascular proliferation and permeability. The aim of this study was to quantify the release of two diffusible angiogenic growth factors (VEGF and FGF-2) after rapid maxillary expansion (RME). Thirty animals were randomly assigned to two groups. Control group (5 rats - intact suture) and Experimental groups (25 rats with RME) which were evaluated in different periods of treatment. Five animals were euthanized in different periods of healing at 0, 1, 2, 3, 5 and 7 days after RME. RT-PCR was used to evaluate the gene expression of angiogenic growth factors released on different periods of study. Data were submitted to statistical analysis using ANOVA followed by Tukey test and significance was assumed at a=0.05. RT-PCR showed that mRNAs of VEGF and FGF-2 were expressed in intact palatal suture tissue. mRNAs of VEGF and FGF-2 was upregulated in early periods (24 h) after RME (p<0.001 and p<0.01, respectively). The molecular levels of VEGF never returned to its original baseline values, and FGF-2 expression decreased up to day 5 (p<0.001) and suddenly increased at day 7, returning to its original level. RME increased VEGF secretion, but decreased FGF-2 secretion when compared to intact tissue. The results showed that these angiogenic growth factors are released and regulated in the palatal suture tissue after RME and could make an important contribution to the knowledge of overall reparative response of the suture tissue during the bone remodeling process.


Resumo Fator de crescimento endothelial (VEGF) e fator de crescimento de fibroblasto (FGF-2) tem a capacidade de aumentar a proliferação e permeabilidade vascular. O objetivo deste estudo foi quantificar a liberação dos dois fatores de crescimento (VEGF e FGF-2) após expansão rápida da maxilla (ERM). Trinta animais foram divididos aleatoriamente em dois grupos. Grupo Controle (5 ratos - sutura intacta) e grupos Experimentais (25 ratos submetidos a ERM) que foram avaliados em períodos diferentes de tratamento. Cinco animais foram eutanaziados em diferentes períodos de avaliação aos 0, 2, 3, 5 e 7 dias após ERM. RT-PCR foi usado para avaliar a expressão gênica dos fatores de crescimento liberados nos diferentes períodos de estudo. Os dados foram submetidos à análise estatística usando ANOVA seguido do pós-teste de Tukey com nível de significância de a=0.05. RT-PCR mostrou que os RNAm de VEGF e FGF-2 estavam expressos na sutura palatina mediana intacta. Os RNAm de VEGF e FGF-2 foram estimulados nos períodos iniciais (24h) após ERM (p<0.001 e p<0.01, respectivamente). Os nívies moleculares de VEGF nunca retornaram aos valores originais, e a expressão de FGF-2 reduziu até o dia 5 (p<0.001) e de repente aumentou até o dia 7, retornando aos níveis originais. ERM aumentou a secreção de VEGF, mas diminuiu a secreção de FGF-2 quando comparado ao tecido intacto. Os resultados mostraram que estes fatores de crescimento são liberados e regulados na sutura palatina mediana após ERM e podem ser de importante contribuição para o entendimento da resposta reparadora geral do tecido da sutura durante o processo de remodelação óssea.


Subject(s)
Animals , Rats , Fibroblast Growth Factor 2 , Palatal Expansion Technique , Palate/surgery , Sutures , Vascular Endothelial Growth Factor A
4.
Chinese Journal of Cancer Biotherapy ; (6): 984-991, 2020.
Article in Chinese | WPRIM | ID: wpr-825749

ABSTRACT

@#[Abstract] Objective: To investigate the molecular mechanism of microRNA-101 (miR-101) inhibiting the migration and invasion of non-small cell lung cancer (NSCLC) via targeting fibroblast growth factor 2 (FGF2). Methods: qPCR was used to detect the expression levels of miR-101 and FGF2 in human normal lung epithelial BEAS-2B cells and NSCLC cell lines (A549, H661 and SK-MES-1) as well as A549 cells after transfection. MiR-NC, miR-101 mimics, miR-IN-NC, miR-101 inhibitor or pcDNA-3.1 empty plasmid, pcDNA-FGF2 were respectively transfected into A549 cells. Wound healing assay and Transwell assay were used to examine the effects of overexpression of miR-101 and FGF2 on the migration and invasion of A549 cells. Western blotting(WB) was used to detect the expression levels of FGF2, E-cadherin, N-cadherin, Vimentin, ERK1/2 and p-ERK1/2 in A549 cells in each group. Results: The expression level of miR-101 in NSCLC cell lines were significantly lower than that in normal lung epithelial cells (all P<0.05), while the expression level in A549 cells was the lowest. Overexpression of miR-101 significantly inhibited the migration (P<0.05) and invasion (P<0.01) of A549 cells, increased the expression level of E-cadherin but decreased the expression level of Vimentin (P<0.05),N-cadherin (P<0.01) and p-ERK1/2 (P<0.05). Inhibition of miR-101 significantly enhanced the invasion and migration of A549 cells (all P<0.05), decreased the expression level of E-cadherin but increased the expression levels of Vimentin, N-cadherin and p-ERK1/2 (all P<0.05). The results of WB and Dual-luciferase reporter gene assay verified that FGF2 is a direct target gene of miR-101, and over‐expression of FGF2 significantly enhanced the invasion and migration of A549 cells (all P<0.01), decreased the expression of E-cadherin (P<0.01) but increased the expressions of Vimentin (P<0.01), N-cadherin (P<0.05) and p-ERK1/2 (P<0.01). Compared with the FGF2 overexpression alone group, co-overexpression of miR-101 and FGF2 significantly reduced the invasion and migration of A549 cells (all P<0.01), increased the expression of E-cadherin (P<0.01), and decreased the expressions of Vimentin (P<0.01), N-cadherin (P<0.05) and p-ERK1/2 (P<0.01). Conclusion: By targeting FGF2, miR-101 inhibits the invasion and migration of NSCLC cells through suppressing the epithelial-mesenchymal transition (EMT) and ERK signaling pathway.

5.
International Journal of Stem Cells ; : 360-366, 2019.
Article in English | WPRIM | ID: wpr-764068

ABSTRACT

The robust capacity of skeletal muscle stem cells (SkMSCs, or satellite cells) to regenerate into new muscles in vivo has offered promising therapeutic options for the treatment of degenerative muscle diseases. However, the practical use of SkMSCs to treat muscle diseases is limited, owing to their inability to expand in vitro under defined cultivation conditions without loss of engraftment efficiency. To develop an optimal cultivation condition for SkMSCs, we investigated the behavior of SkMSCs on synthetic maltose-binding protein (MBP)-fibroblast growth factor 2 (FGF2)-immobilized matrix in vitro. We found that the chemically well-defined, xeno-free MBP-FGF2-immobilized matrix effectively supports SkMSC growth without reducing their differentiation potential in vitro. Our data highlights the possible application of the MBP-FGF2 matrix for SkMSC expansion in vitro.


Subject(s)
In Vitro Techniques , Maltose-Binding Proteins , Muscle, Skeletal , Muscles , Stem Cells
6.
J. venom. anim. toxins incl. trop. dis ; 24: 1-16, 2018. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1484750

ABSTRACT

Background Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Methods Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F +T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. Results The experiments indicated...


Subject(s)
Humans , Fibrin Tissue Adhesive , Bioengineering , Stem Cells , Sciatic Nerve , Nerve Regeneration , Peripheral Nerve Injuries
7.
J. venom. anim. toxins incl. trop. dis ; 24: 11, 2018. tab, graf, ilus
Article in English | LILACS | ID: biblio-894174

ABSTRACT

Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Methods Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F +T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. Results The experiments indicated that sensory function improved when transgenic hESCs were used. The regeneration of sensory fibers indeed led to increased reflexes, upon stimulation of the paw ipsilateral to the lesion, as seen by von-Frey evaluation, which was supported by immunohistochemistry. Conclusions Overall, the present data demonstrated that transgenic embryonic stem cells, engineered to overexpress FGF-2 in an inducible fashion, could be employed to support regeneration aiming at the recovery of both motor and sensory functions.(AU)


Subject(s)
Animals , Male , Rats , Sciatic Nerve/transplantation , Transplantation, Heterologous/rehabilitation , Fibrin Tissue Adhesive , Embryonic Stem Cells , Nerve Regeneration , Mice, Inbred C57BL
8.
São Paulo; s.n; s.n; 2018. 165 p. ilus, tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-911612

ABSTRACT

O FGF2 (Fibroblast Growth Factor 2) é um clássico fator peptídico de crescimento que ativa vias intracelulares de sinalização molecular promovendo a transição G0 → G1 e o comprometimento com o ciclo celular. Não surpreendentemente, seus papéis pró-tumoral e angiogênico estão bem caracterizados e estabelecidos na literatura. No entanto, um crescente corpo de evidências tem indicado que o FGF2 também pode exercer efeitos anti-tumorais in vitro e in vivo, em modelos murinos e também humanos. Neste contexto, nosso grupo publicou em 2008 que o FGF2 exerce um efeito antiproliferativo seletivo em células murinas malignas dependentes de alta atividade de K-Ras e H-Ras. Os genes ras compõem a família de oncogenes mais frequentemente mutada em tumores malignos humanos, alcançando aproximadamente 30% de todos os casos. O desenvolvimento de terapias contra tumores dependentes de Ras fracassou, apesar dos intensos esforços e investimentos desde a descoberta em 1982 de suas mutações ativadoras em múltiplos cânceres. O objetivo deste trabalho foi desvendar os mecanismos moleculares pelo quais o FGF2 inibe irreversivelmente a proliferação de células malignas dependentes da atividade de Ras, empregando como modelos experimentais a linhagem murina Y1 de células adrenocorticais, e 4 linhagens humanas derivadas de sarcomas de Ewing. Identificamos que o efeito citotóxico do FGF2 não se processa por um mecanismo novo e independente das viasproliferativas classicamente ativadas por fatores peptídicos de crescimento. Ao contrário, seu efeito tóxico é resultado de sinalização mitogênica exagerada decorrente de estimulação sustentada por FGF2. A ativação da via de MAPK, principal sinalização mitogênica intracelular, a níveis elevados e sustentados provoca estresse mitogênico, que se propaga para a fase S na forma de estresse replicativo. Nesta situação, a célula passa a depender exageradamente da sinalização protetora de ATR, de modo que a combinação de estimulação com FGF2 e inibição de ATR foi altamente letal para as células malignas dependentes de Ras empregadas neste trabalho. Também analisamos as bases moleculares de resistência a FGF2 exibida por células Y1 anteriormente selecionadas para resistir ao efeito tóxico do FGF2 (Y1FRs). Descobrimos que a pressão seletiva do FGF2 não teve efeito na expressão de seus receptores, mas provocou a eliminação de um dos dois cromossomos que portam a amplificação gênica de ras nesta linhagem, enquanto o segundo cromossomo foi mantido por ser a única fonte de genes ribossomais ativos. Suas cópias de ras, no entanto, mostraram-se transcricionalmente silenciadas. Além disso, as sublinhagens Y1FRs não expressam o principal RasGEF, GRP4, encontrado nas células parentais Y1, o que pode ter influenciado o surgimento do fenótipo resistente ao FGF2. As linhagens resistentes mostraram grande redução no número de cromossomos e aumento da frequência de fusões entre cromossomos não homólogos em relação às células parentais


FGF2 (Fibroblast Growth Factor 2) is a classic peptide growth factor that activates intracellular molecular signaling pathways promoting the G0 → G1 transition and cell cycle commitment. Not surprisingly, its pro-tumor and angiogenic roles are well characterized and established in the literature. However, a growing body of evidence has indicated that FGF2 may also exert anti-tumor effects in vitro and in vivo in murine and human models. In this context, our group reported in 2008 that FGF2 exerts a selective antiproliferative effect in murine cells dependent on high activity of K-Ras and H-Ras. Ras genes make up the most frequently mutated oncogene family in human malignant tumors, reaching approximately 30% of all cases. The development of therapies against Ras-dependent tumors has failed despite intense efforts and investments since the discovery in 1982 of its activating mutations in multiple cancers. The objective of this work was to uncover the molecular mechanisms by which FGF2 irreversibly inhibits the proliferation of malignant cells dependent on Ras activity, using as experimental models the Y1 murine lineage of adrenocortical malignant cells and 4 human lineages derived from Ewing sarcomas. We showed that the cytotoxic effect of FGF2 did not involve novel cell cycle regulatory pathways; instead, this cytotoxic effect is a result of sustainedhyper mitogenic stimulation by FGF2. Activation of the KRas/MAPK pathway, the major intracellular mitogenic signaling, at high and sustained levels provokes mitogenic stress, which is propagated to S phase as replicative stress. In this situation, the cell dependence on the ATR protective signaling is enhanced, so that the combination of stimulation with FGF2 and inhibition of ATR was highly lethal for the Ras dependent malignant cells employed in this work. We also analyzed the molecular basis of FGF2 resistance exhibited by Y1 cells previously selected for resistance to FGF2. We found that the selective pressure of FGF2 had no effect on the expression of its receptors but promoted the elimination of one of the two marker chromosomes that carry the K-ras amplified copies, while the second chromosome was maintained because it is the only source of active ribosomal genes; however, its K-ras amplified copies were transcriptionally silenced. In addition, the Y1FRs sublines did not express the main RasGEF, GRP4, found in the parental Y1 cells, which might have played a role in the emergence of the FGF2-resistant phenotype. The resistant Y1FRs sublines showed a large reduction in chromosome numbers and increased frequency of fusions between non-homologous chromosomes in relation to parental cells


Subject(s)
Fibroblast Growth Factor 2/analysis , Fibroblast Growth Factor 2/adverse effects , Genes, ras/genetics , Adrenocortical Carcinoma/classification , Molecular Mechanisms of Pharmacological Action , Synthetic Lethal Mutations
9.
Chinese Traditional Patent Medicine ; (12): 1233-1237, 2018.
Article in Chinese | WPRIM | ID: wpr-710285

ABSTRACT

AIM To study the influence and action mechanism of effective components in compatible solution of Sparganii Rhizoma-Curcumae Rhizoma on pelvic adhesions of model rats with chronic pelvic inflammatory disease.METHODS Laboratory rats were randomly assigned into six groups,a sham-operated group,a model group,a positive Fukeqianjin tablets group,compatible solution groups (40 g/kg high-dose group,20 g/kg medi um-dose group,and 10 g/kg low-dose group).Except rats of the sham-operated group,those in the other groups were induced into models of chronic pelvic inflammatory disease by mechanical bacterial strain implantation,after which a 20 d corresponding drug administration by oral gavage for each group was initiated.After completion of the last drug administration,Verco criterion was taken as the reference to evaluate pelvic adhesions,HE staining was performed on uterine tissues for pathological scoring,ELASA method was applied to measuring serum IL-1β and TNF-α levels,and Western blot method was used to detect the expression levels of proteins FGF-2 and IGF-1 in uterine tissues.RESULTS Compared with the model group,the high-dose compatible solution group had a much sharper fall in Verco scores (P < 0.05),and remarkably decreased serum IL-1β and TNF-α levels (P < 0.01);both high-dose and medium-dose groups manifested with notably alleviated degenerative necrosis and lowered scores of chronic inflammation infiltration and epithelial hyperproliferation (P < 0.01 or P < 0.05),and a distinct reduction in the expression of proteins FGF-2 and IGF-1 (P < 0.05,P < 0.01).CONCLUSION The significant improvement of the chronic pelvic inflammatory disease in model rats due to the effective components in the compatibile solution of Sparganii Rhizoma-Curcumae Rhizoma may be associated with inhibited release of inflammatory mediators IL-1β and TNF-α,and the reduced expression of proteins FGF-2 and IGF-1 as well.

10.
The Journal of Practical Medicine ; (24): 4019-4023, 2017.
Article in Chinese | WPRIM | ID: wpr-665315

ABSTRACT

Objective To expore the effects of FGF-2 and TGF-β1 on the differentiation of rat bone mar-row mesenchymal stem cells(BMSCs)towards cardiocytes. Methods BMSCs were isolated from bones of SD rats and cultured and identified by flow cytometry.The cells were divided into four groups:group A(FGF-2),group B (TGF-β1),group C(FGF-2+TGF-β1)and group D(blank control).The morphological changes were observed by the microscope. The expressions of Desmin,α-sarcomeric actin and cTnI were detected by immunocytochemical stainning.The expressions of GATA-4 and Nkx2.5was detected by RT-qPCR.Result The positive expression rate of CD90,CD29 and CD45 was 84.7%,86.5%,0.3% respectively. After induction,group C presence of myotube structures and the shape is fusiform.The positive rate of combined induction group was higher than the others (P < 0.05). The expression of GATA-4 and Nkx2.5 genes was higher than that in the other groups(P < 0.05). Conclution FGF-2 and TGF-β1 can be used to induce BMSCs into cardiocytes,and the combined group has the better effect.

11.
The Journal of Practical Medicine ; (24): 36-40, 2017.
Article in Chinese | WPRIM | ID: wpr-507161

ABSTRACT

] Objective To explore the role and mechanisms of FGF2 in chemo?resistance in breast cancer. Methods The inhibitors for different signal pathway were used to treat two drug?resistant breast cancer cell lines MCF?7/5?Fu and T47D/5?Fu established in our lab. MTS assay was used to determine chemo?sensitivity and Hoechst stain was used to measure apoptosis. Protein activation and FGF2 protein level in cell culture medium were detected by western blot and ELISA respectively. Results Akt inhibitor MK?2206 (20 nM) and mTOR inhibitor AZD8055 (2 nM) significantly reversed the chemo?resistance of MCF?7/5?Fu and T47D/5?Fu cell lines to 5?Fu and paclitaxel, but ERK1/2 inhibitor SCH772984 showed no significant effect. Compared to parent cell lines MCF?7 and T47D, p?Akt and p?S6K (represented as mTORactivity) levels were obviously up?regulated in MCF?7/5?Fu and T47D/5?Fu cell lines, and so do the FGF2 mRNA level and FGF2 protein level from culture medium. Moreover, FGFR inhibitor AZD4547 (4 nM) markedly reversed the chemo?resistance of MCF?7/5?Fu and T47D/5?Fu cell lines to 5?Fu and paclitaxel and down?regulated activation of FGFR?Akt?mTOR signal pathway. In agreement, FGF2 protein (10ng/ml) enhanced the chemo?resistance of MCF?7 and T47D cell lines to 5?Fu and paclitaxel and up?regulated activation of FGFR?Akt?mTOR signal pathway. Conclusion Activation of FGF2?FGFR?Akt?mTOR signal pathway promoted chemo?resistance of breast cancer cells.

12.
São Paulo; s.n; s.n; 2014. 102 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-847313

ABSTRACT

Sabe-se há décadas que mutações nos genes ras estão presentes em cerca de 20% dos cânceres humanos, mas o desenvolvimento de terapias eficazes para o tratamento de câncer dependente dos oncogenes ras permanece um desafio científico importante. Nesse contexto, o nosso grupo publicou recentemente resultados interessantes mostrando que FGF2 exógeno ou PMA, contrariamente à expectativa geral, inibem a proliferação de células de camundongo malignas dependentes dos oncogenes H- ou K-Ras. Para dar continuidade a estes estudos o projeto desta tese foi planejado para investigar os mecanismos subjacentes a possíveis efeitos citotóxicos de FGF2 e PMA em células humanas transformadas por ras. Para esse fim, a linhagem humana imortalizada HEK 293 foi condicionalmente transformada pela expressão ectópica da construção quimérica de DNA ER:H-rasV12, que codifica a oncoproteína de fusão ER:H-RasV12, cuja atividade é induzível por 4-hidroxi-tamoxifen (4OHT). Essa abordagem nos permitiu verificar os efeitos de FGF2 e PMA em sublinhagens HEK/ER:HrasV12 fenotipicamente "normais" ou transformadas por níveis crescentes da oncoproteína H-RasV12. Os principais resultados mostraram que tanto FGF2 como PMA tem efeito dual promovendo ou inibindo a proliferação das células transformadas em função da concentração intracelular crescente de H-RasV12. Ensaios de crescimento de colônias em suspensão de agarose mostraram que: a) as células parentais HEK293 não desenvolveram colônias mesmo quando tratadas com FGF2 ou PMA, resultados que estão de acordo com seu fenótipo não tumoral; b) mas, as sublinhagens HEK/ER:HrasV12 deram origem a colônias mesmo quando tratadas com concentrações pequenas de 4OHT, que condicionaram níveis intracelulares baixos de ER:HRasV12; nestas condições experimentais, FGF2 foi um forte promotor do crescimento de colônias, condizente com sua reconhecida atividade promotora do crescimento de células tumorais em suspensão; ainda nestas condições, PMA não teve efeito significante sobre o crescimento de colônias; c) coerentemente, concentrações elevadas de 4-OHT levaram aos níveis intracelulares mais altos de ER:HRasV12 e, por conseguinte, a desenvolvimento máximo de colônias de células HEK/ER:HrasV12, no entanto, nestas condições, ambos FGF2 e PMA inibiram completamente o crescimento de colônias. Por outro lado, transformação de HEK293 com um vetor de expressão constitutiva de HrasV12 levou à seleção e isolamento das sublinhagens tumorais HEK/HrasV12, cujo fenótipo se caracterizou por: a) nenhum efeito de FGF2 sobre a sua proliferação e b) forte inibição de sua proliferação por PMA. A ação citotóxica de PMA exclusivamente observada em células HEK 293 transformadas por H-rasV12 se caracterizou por: a) total dependência de PKC, provavelmente mediada pela ativação proteolítica específica de PKC δ; b) envolvimento de níveis elevados e sustentados de ROS com disparo tardio de apoptose


It is known for nearly 20 years that mutated ras oncogenes are found in 20% of human malignancies, however efficacious therapies are not yet available for Ras-driven cancer. Along of these lines, our group recently published provocative results showing, against common belief, that FGF2 and PMA inhibited proliferation of Ras-dependent malignant mouse cells. Aiming to gain insight into this intriguing phenomenon, the present thesis project was planned to investigate the possible cytotoxicity of FGF2 and PMA in human Ras-driven malignant cells. To this end an immortalized non-tumorigenic human cell line (HEK293) was stably transformed with the DNA construction ER:H-rasV12, which encodes the fusion protein ER:H-RasV12, whose activity requires activation by 4-hidroxitamoxifen (4-OHT). This approach allowed us to evaluate FGF2 and PMA effects on HEK/ER:HrasV12 sublines under switching from "normal" to transformed phenotypes upon 4-OHT induction. Our main results have shown that both FGF2 and PMA displayed dual effects promoting or inhibiting proliferation of HEK/ER:HrasV12 cells in function of ER:HRasV12 intracellular levels. Clonogenic assays in agarose suspension have shown: a) parental HEK293 line did not develop colonies under FGF2 and PMA treatment or not, in agreement with its non-tumorigenic nature; b) however, HEK/ER:HrasV12 sublines developed colonies even under low 4-OHT concentrations, which led to low ER:HRasV12 intracellular levels; under these conditions FGF2 strongly promoted colony growth and PMA had no effect; c) furthermore, in HEK/ER:HrasV12 sublines, elevated 4-OHT concentrations led to high ER:HRasV12 intracellular levels and maximal colony growth; but, under these experimental conditions both FGF2 and PMA abolished colony growth. On the other hand, HEK293 transformation with a vector that constitutively express HrasV12 yielded HEK/ER:HrasV12 sublines displaying the following phenotypic traits: a) non FGF2 effects on proliferation and b) severe proliferation inhibition by PMA. PMA toxicity, exclusively observed in HrasV12 -transformed HEK293 cells, was characterized by: a) total dependency on PKC, likely mediated by specific proteolytic activation of PKCδ; b) involvement of high and sustained ROS levels correlated with late apoptosis triggering


Subject(s)
Animals , Male , Female , Mice , Fibroblast Growth Factor 2/analysis , Genes, ras/genetics , HEK293 Cells , Neoplasms/complications , Cell Culture Techniques/methods , Flow Cytometry/methods , Reverse Transcription/genetics , Tamoxifen , Transduction, Genetic/methods
13.
Asian Pacific Journal of Tropical Medicine ; (12): 71-75, 2014.
Article in English | WPRIM | ID: wpr-819727

ABSTRACT

OBJECTIVE@#To observe the change of fibroblast growth factor-2 (FGF-2), insulin-like growth factor-1 (IGF-1) in serum and bone callus after fracture in diabetic rats, and to explore molecular biological mechanism of healing of diabetic fracture.@*METHODS@#Thirty male SD rats were designed into normal (n=15) and control (n=15) groups randomly. Venous blood was extracted on the lst, 2nd, 4th, 6th, 8th week after surgery. It was certificated and the serum was obtained. Left lower extremity was observed by X- ray. Bone callus at broken ends was observed under light microscope. Expressions of FGF-2 and IGF-1 in tissue were detected by immunohistochemistry method, and ELISA was used to detect expression of FGF-2 and IGF-1 in serum.@*RESULTS@#The results showed a significant increase in the density and area of newly formed bone in the distraction gaps of normal rats compared to control rats. Increased cell proliferation was also found in the distraction gaps of normal rats versus control rats. There was significant difference in serum levels of FGF-2 and IGF-1 between two groups.@*CONCLUSIONS@#The decrease of FGF-2 and IGF-1 both in the serum and in the fracture region is one of the reasons for bad bone healing or delayed union in rats' fracture with diabetes. There are some synergistic effects possibly between FGF-2 and IGF-1.


Subject(s)
Animals , Male , Rats , Behavior, Animal , Diabetes Mellitus, Experimental , Metabolism , Fibroblast Growth Factor 2 , Blood , Metabolism , Fracture Healing , Physiology , Fractures, Bone , Metabolism , Immunohistochemistry , Insulin-Like Growth Factor I , Metabolism , Pain Measurement , Random Allocation , Rats, Sprague-Dawley
14.
Chinese Pharmacological Bulletin ; (12): 1535-1538, 2014.
Article in Chinese | WPRIM | ID: wpr-460029

ABSTRACT

Aim To construct eukaryotic expressing plasmid of hi FGF2 ( high molecular weight isoform fi-broblast growth factor-2,hi FGF2) gene and to investi-gate its effect on apoptosis after its overexpression in HEK293 cells. Methods The DNA template primer was designed and synthesized. The pDsRed1-N1 plas-mids were digested by the restriction enzymes of Nhel and Hind III. The hi FGF2 was ligated with linearized pDsRed1-N1 by T4 DNA Ligase. The recombinant plasmid was identified by endonuclease digestion and sequenced. The recombinant hi FGF2 plasmid was transient transfected into HEK293 cells by Lipofectami-neTM 2000 Reagent. The transfection efficiency was de-tected by fluorescence inversion microscope. The cell apoptosis was detected by Annexin V-FITC/PI apopto-sis detection kit with flow cytometry analysis. Results The pDsRed1-N1 eukaryotic expression vector was consistent with the design. The recombinant hi FGF2 plasmid was transfected in HEK293 cells. The trans-fection rate was more than 70%. The FITC/PI dyeing rate in hi-FGF2 over-expression HEK297 cells was a-bout ( 29. 12 ± 2. 81 )%. Conclusions pDsRed1-N1 eukaryotic expression vector is successfully constructed and transfected into HEK293 cells. Over-expression of hi FGF2 induces cell apoptosis.

15.
Biol. Res ; 46(4): 421-429, 2013. ilus, graf, tab
Article in English | LILACS | ID: lil-700404

ABSTRACT

Among the osteogenic growth factors used for bone tissue engineering, bone morphogenetic proteins (BMPs) are the most extensively studied for use in orthopaedic surgery. BMP-2 and BMP-7 have been widely investigated for developing therapeutic strategies and are the only two approved for use in several clinical applications. Due to the chemical and biological characteristics of these molecules, their authorised uses are always in combination with a carrier based on collagen type I. Although the use of these growth factors is considered safe in the short term, the very high doses needed to obtain significant osteoinduction make these treatments expensive and their long-term safety uncertain, since they are highly pleiotropic and have the capacity to induce ectopic ossification in the surrounding tissues. Therefore it is necessary to improve the currently used BMP-collagen system in terms of efficiency, biosecurity and costs. There are several strategies to increase the clinical effectiveness of these treatments. In this review we summarize the most promising results and our related work focused on this field through two different approaches: i) the development of recombinant BMPs with additional features, and ii) complementing these systems with other growth factors or molecules to enhance or accelerate osteogenesis.


Subject(s)
Animals , Humans , Bone Morphogenetic Proteins/physiology , Collagen/physiology , Osteogenesis/physiology , Tissue Engineering , Cell Differentiation , Cell Proliferation
16.
São Paulo; s.n; 2012. 164 p.
Thesis in Portuguese | LILACS, SES-SP, SESSP-IBPROD, SES-SP, SESSP-IBACERVO | ID: biblio-1080927

ABSTRACT

FGF2 ( Fibroblast Growth Factor 2) é o membro fundador de uma grande família de fatores de crescimento proteícos. Sua atividade se dá através da ligação e ativação de receptores especificos da membrana (FGFRs) com atividade de tirosina quimase. No organismo adulto, a simalização de FGF2 está envolvida na indução de processos de sobrevivência, proliferação e diferenciação celular; além de cicatrização e angiogênese. Por atuar como um clássico fator de crescimento, a atividade de FGF2 está frequentemente implicada em mecanismos pró-tumorais....


FGF2 is the first member of a large family of peptide growth factors. It binds and activates specific membrane receptors ( FGFRs) belonging to a family of tyrosine kinase receptors (RTK). in adult organisms, FGF2 signaling is involved in the induction of cell surveillance, proliferation and differentation; and also wound healing and angiogenesis. FGF2 is a bona fide growth factor and, as such, it is often implicated in pro-tumor mechanisms...


Subject(s)
Humans , Neoplasms/chemistry , ras Proteins/adverse effects , ras Proteins/immunology , ras Proteins/toxicity
17.
Biol. Res ; 45(1): 51-60, 2012. ilus
Article in English | LILACS | ID: lil-626747

ABSTRACT

Acute renal failure (ARF) can be caused by injuries that induce tissue hypoxia, which in turn can trigger adaptive or inflammatory responses. We previously showed the participation of basic fibroblast growth factor (FGF-2) in renal repair. Based on this, the aim of this study was to analyze the effect of FGF-2 signaling pathway manipulation at hypoxia-induced protein levels, as well as in key proteins from the vasoactive systems of the kidney. We injected rat kidneys with FGF-2 recombinant protein (r-FGF) or FGF-2 receptor antisense oligonucleotide (FGFR2-ASO) after bilateral ischemia, and evaluated the presence of iNOS, EPO and HO-1, in representation of hypoxia-induced proteins, as well as COX-2, renin, kallikrein, and B2KR, in representation of the vasoactive systems of the kidney. A reduction in iNOS, HO-1, EPO, renin, kallikrein, B2KR, and in renal damage was observed in animals treated with r-FGF. The opposite effect was found with FGF-2 receptor down-regulation. In contrast, COX-2 protein levels were higher in kidneys treated with r-FGF and lower in those that received FGFR2-ASO, as compared to saline treated kidneys. These results suggest that the protective role of FGF-2 in the pathogenesis of ARF induced by I/R is a complex process, through which a differential regulation of metabolic pathways takes place.


Subject(s)
Animals , Male , Rats , Acute Kidney Injury/metabolism , Cell Hypoxia/physiology , /metabolism , /pharmacology , Kidney/drug effects , Nitric Oxide Synthase/metabolism , Reperfusion Injury/physiopathology , Acute Kidney Injury/pathology , Disease Models, Animal , Erythropoietin/metabolism , /analysis , /metabolism , Heme Oxygenase-1/metabolism , Kallikreins/analysis , Kidney/blood supply , Rats, Sprague-Dawley , /analysis
18.
São Paulo; s.n; s.n; 2012. 162 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-846848

ABSTRACT

FGF2 (Fibroblast Growth Factor 2) é o membro fundador de uma grande família de fatores de crescimento protéicos. Sua atividade se dá através da ligação e ativação de receptores específicos de membrana (FGFRs) com atividade de tirosina quinase. No organismo adulto, a sinalização de FGF2 está envolvida na indução de processos de sobrevivência, proliferação e diferenciação celular; além de cicatrização e angiogênese. Por atuar como um clássico fator de crescimento, a atividade de FGF2 está freqüentemente implicada em mecanismos pró-tumorais. Entretanto, alguns grupos, incluindo o nosso, têm reportado que FGF2 também pode apresentar efeitos antiproliferativos a até citotóxicos seletivamente em células malignas. Em 2008, publicamos um compreensivo relato mostrando que FGF2 bloqueia irreversivelmente a proliferação de linhagens murinas malignas dependentes de Ras. Alterações que levem a atividade aumentada de proteínas Ras estão presentes em diversos cânceres humanos e, freqüentemente, resultando em problemas no tratamento e prognóstico ruim. No presente trabalho, utilizamos principalmente a linhagem murina maligna dependente de Ras Y1 D1G, que apresenta um controle estrito de quiescência/proliferação em função da presença de soro; e é por isso mesmo um bom modelo para a análise dos efeitos de FGF2 sobre o ciclo celular. Análises por citometria de fluxo mostraram que, nessas células, apesar de disparar a transição G0→G1→S, FGF2 provoca um atraso na fase S seguido de um bloqueio do ciclo em G2. Embora bloqueie a progressão no ciclo (proliferação), FGF2 induz em Y1 D1G o crescimento celular em termos de massa e volume. Assim, nessas células FGF2 "desconecta" crescimento celular de proliferação. Esse desarranjo do ciclo celular provocado por FGF2 nas células Y1 D1G tem como resultado a instabilidade genotípica e morte celular; evidenciada pela perda da integridade de membrana plasmática e altas taxas de fragmentação de DNA observadas após o estímulo por esse fator. Esse efeito tóxico de FGF2 depende da atividade da proteína Src; porque a inibição química dessa proteína apresentou proteção total frente aos efeitos tóxicos de FGF2. Análises por espectrometria de massas mostraram que FGF2 induz aumento dos níveis de proteínas relacionadas à síntese protéica, e também de proteínas relacionadas ao estresse proteotóxico. Sabe-se que células malignas lidam com níveis basais altos de diferentes tipos de estresse; incluindo o estresse proteotóxico. Esse quadro mostra que o efeito tóxico disparado por FGF2 em Y1 D1G está relacionado a um acumulo de proteínas/célula, perda da homeostase de proteínas e estresse proteotóxico. Corrobora essas proposições o fato de que a inibição química de Src, que protege totalmente as células do efeito tóxico de FGF2, impede completamente o acúmulo de proteínas/célula. Além disso, em células Y1 D1G resistentes ao efeito tóxico de FGF2, e que inclusive dependem deste para proliferar em cultura, a atividade de FGF2 tem efeito oposto; ou seja, provoca diminuição dos níveis estacionários de proteínas/célula. Juntos, esses resultados demonstram que FGF2 é capaz de atacar uma vulnerabilidade de células malignas dependentes de Ras; e no caso estudado, essa vulnerabilidade decorre do desequilíbrio na homeostase de proteínas


FGF2 is the first member of a large family of peptide growth factors. It binds and activates specific membrane receptors (FGFRs) belonging to a family of tyrosine kinase receptors (RTK). In adult organisms, FGF2 signaling is involved in the induction of cell surveillance, proliferation and differentiation; and also wound healing and angiogenesis. FGF2 is a bona fide growth factor and, as such, it is often implicated in pro-tumor mechanisms. However, several groups, including ours, have reported that FGF2 can also display antiproliferative and even cytotoxic effects selectively in malignant cells. In 2008, we fully reported that FGF2 irreversibly blocks the proliferation of Ras-driven mouse malignant lineages. Alterations leading to Ras proteins overactivity are present in many human cancers frequently with bad prognosis. In the present work, we used mainly the Ras-driven mouse malignant lineage Y1 D1G that shows a strict control of quiescence/proliferation by serum factors, making it a great model to analyze the FGF2 effects upon cell cycle control. Flow cytometry analyses showed that in these cells, in spite of triggering G0→G1→S transition, FGF2 causes a delay on S phase followed by cell cycle arrest in G2. Despite blocking cell division, FGF2 induces cell growth in terms of mass and volume. Therefore, in these cells FGF2 "disconnects" cell growth from proliferation. This malfunction of cell cycle control caused by FGF2 on Y1 D1G cells leads to genotypic instability and cell death, highlighted by loss of plasma membrane integrity and high rates of DNA fragmentation. This FGF2 toxic effect depends on the activity of Src protein, because Src chemical inhibition completely protects cells from the FGF2 toxic effects. Mass spec analyses showed that FGF2 increases the levels of proteins involved in the protein synthesis machinery, and also of proteins active in proteostasis, indicating proteotoxic stress. It is known that malignant cells deal with high basal levels of different stresses, including the proteotoxic stress. This picture shows that the toxic effects triggered by FGF2 in Y1 D1G involve accumulation of proteins/cell, loss of protein homeostasis and proteotoxic stress. Corroborating these propositions, chemical inhibition of Src, which completely protects the cells from FGF2 toxic effects, totally abrogates the accumulation of proteins/cell. Moreover, in FGF2-resistant Y1 D1G cells, which depend on this factor for proliferation, FGF2 shows the opposite effect, causing decrease in steady state levels of protein/cell. Altogether, these results show that FGF2 causes a severe proteostasis imbalance in these Ras-driven mouse malignant cells


Subject(s)
Cell Division/genetics , Fibroblast Growth Factor 2/toxicity , ras Proteins/genetics , Cell Cycle/genetics , Cell Proliferation , Cell Proliferation/genetics , Disaster Vulnerability , DNA Damage , Flow Cytometry/methods , Neoplasms/complications
19.
São Paulo; s.n; s.n; 2012. 140 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-846867

ABSTRACT

Um passo limitante no desenvolvimento de fármacos para terapias do câncer está na descoberta de vulnerabilidades específicas de células tumorais que sirvam à identificação de alvos moleculares apropriados à intervenção farmacológica. Esta é a motivação central desta tese, cuja abordagem experimental focaliza a ação oncogênica das proteínas Ras. Amplificação ou mutação ativadora nos proto-oncogenes ras estão entre as alterações genéticas mais frequentes em cânceres. Essas lesões genéticas aparecem na origem etiológica de múltiplas formas de fenótipos malignos. Mas, essas lesões oncogênicas também conferem susceptibilidades letais às células malignamente transformadas frente a determinados agentes que não interferem significativamente nas funções vitais de células normais. Nos últimos anos nosso laboratório vem estudando os mecanismos moleculares da ação antiproliferativa do fator de crescimento FGF2 (Fibroblast Growth Factor2) e do éster de forbol PMA (Phorbol-12-Myristate-13-Acetate) em linhagens de células murinas malignas dependentes de ras oncogênico. Nesta tese investigamos quanto de nossas observações anteriores com células murinas são aplicáveis a células humanas. Nesse sentido focalizamos a linhagem HaCaT de queratinócitos humanos imortalizados e seus subclones malignizados por expressão ectópica de H-RasV12; além disso, numa triagem inicial também examinamos treze linhagens celulares humanas derivadas de tumores naturais portadores de mutação ativadora em H-Ras, N-Ras ou K-Ras. Nossos resultados mostram que os queratinócitos da linhagem parental HaCaT expressam receptores de FGFs e respondem mitogenicamente tanto a FGF2 como a PMA; portanto, ambos FGF2 e PMA são benéficos aos queratinócitos HaCaT. Por outro lado, o FGF2 mostrou-se citotóxico para subclones HaCaT que expressam H-RasV12 induzível, mas sublinhagens HaCaT com expressão constitutiva de H-RasV12 mostraram-se resistentes à ação citotóxica de FGF2. Diferentemente de FGF2, PMA bloqueou a proliferação de sublinhagens clonais HaCaT-H-RasV12 em ambos substrato sólido e suspensão de agarose e, também, reduziu a estratificação dos queratinócitos HaCaT-H-RasV12 em culturas organotípicas. PMA foi citotóxico e não citostático, pois induziu morte apoptótica sem causar arresto em nenhuma fase específica do ciclo celular. Em HaCaT parental, PMA induziu aumento transitório dos níveis intracelulares de espécies reativas de oxigênio (ROS), mas nos queratinócitos HaCaT-H-RasV12, PMA causou aumentos mais altos e persistentes de ROS, o que promove forte estresse oxidativo, provavelmente responsável pela toxidez deste ester de forbol. Entre as treze linhagens celulares humanas malignas com H-Ras, N-Ras ou K-Ras mutados, onze foram vulneráveis à ação citotóxica de PMA; mas apenas uma delas, a linhagem de tumor urotelial UM-UC-3, foi sensível ao efeito anti-proliferativo de FGF2. Em conclusão, células malignas humanas com Ras mutado parecem superar rapidamente uma possível toxidez de FGF2, mas não ultrapassam a toxidez causada por PMA


A challenge in drug development for cancer therapy is the discovering of molecular targets suitable for pharmacological interference. This challenge was the main motivation of the present thesis. Amplification or activating mutation in ras proto-oncogenes are among the most frequent genetic lesions in human cancer. Actually, mutated Ras onco-proteins are in the etiological roots of multiple malignant phenotypes; however these onco-proteins also cause specific lethal vulnerabilities even in robust malignant cells. Recently, our laboratory reported that malignant murine cell lines dependent on oncogenic Ras are prone to toxicity initiated by FGF2 (Fibroblast Growth Factor 2) and PMA (Phorbol-12-Myristate-13-Acetate), which are not harmful to normal cells. This cytotoxicity of FGF2 and PMA very likely follows different molecular mechanisms, which, however, are not yet completely understood. The aim of this thesis was to investigate whether these vulnerabilities found in murine malignant cells were also valid for human malignant cell lines dependent on oncogenic Ras. To this end the experimental approach was focused on the HaCaT cell line of immortalized human keratinocytes and its sublines transformed by H-RasV12 ectopic expression. In addition thirteen human cell lines derived from natural tumor carrying mutated H-Ras, N-Ras or K-Ras oncogenes were also screened. The results showed that HaCaT keratinocytes express FGF receptors and respond mitogenically to both FGF2 and PMA. On the other hand, FGF2 was cytotoxic to HaCaT subclones expressing inducible H-RasV12. But, HaCaT sublines constitutively expressing H-RasV12 were resistant to FGF2 toxicity. However, PMA was toxic to all HaCaT-H-RasV12 sublines, inhibiting proliferation in both solid substrate and agarose suspension cultures and, also reducing stratification in organotypic cultures. Furthermore, in HaCaT-H-RasV12 sublines, but not in the parental HaCaT line, PMA caused a persistently high increase in intracellular levels of reactive oxygen species (ROS) and concomitantly induced apoptosis. Moreover, eleven of the thirteen human tumor cell lines with mutated H-Ras, N-Ras or K-Ras, were growth inhibited by PMA, whereas only one of them was inhibited by FGF2, the urothelial tumor cell line UM-UC-3. In conclusion, human malignant cells driven by Ras oncogenes very likely rapidly overcome FGF2 toxicity, whereas they remain stably vulnerable to PMA cytotoxicity


Subject(s)
Carcinoma, Islet Cell , Health Vulnerability , Oxidative Stress/genetics , ras Proteins/analysis , Cytotoxins , Fibroblast Growth Factor 2/analysis , Flow Cytometry/methods , Fluorescent Antibody Technique/methods , Immunoprecipitation/statistics & numerical data , Neoplasms , Phorbol Esters/analysis , Tumor Cells, Cultured , Tumor Stem Cell Assay/instrumentation
20.
Journal of Korean Neurosurgical Society ; : 7-13, 2012.
Article in English | WPRIM | ID: wpr-58027

ABSTRACT

OBJECTIVE: The aim of this study was to determine whether single nucleotide polymorphisms (SNPs) of fibroblast growth factor (FGF) 2 gene and fibroblast growth factor receptor (FGFR) genes are associated with ossification of the posterior longitudinal ligament (OPLL). METHODS: A total of 157 patients with OPLL and 222 controls were recruited for a case control association study investigating the relationship between SNPs of FGF2, FGFR1, FGFR2 and OPLL. To identify the association among polymorphisms of FGF2 gene, FGFR1, FGFR2 genes and OPLL, the authors genotyped 9 SNPs of the genes (FGF2 : rs1476217, rs308395, rs308397, and rs3747676; FGFR1 : rs13317 and rs2467531; FGFR2 : rs755793, rs1047100, and rs3135831) using direct sequencing method. SNPs data were analyzed using the SNPStats, SNPAnalyzer, Haploview, and Helixtree programs. RESULTS: Of the SNPs, a SNP (rs13317) in FGFR1 was significantly associated with the susceptibility of OPLL in the codominant (odds ratio=1.35, 95% confidence interval=1.01-1.81, p=0.048) and recessive model (odds ratio=2.00, 95% confidence interval=1.11-3.59, p=0.020). The analysis adjusted for associated condition showed that the SNP of rs1476217 (p=0.03), rs3747676 (p=0.01) polymorphisms in the FGF2 were associated with diffuse idiopathic skeletal hyperostosis (DISH) and rs1476217 (p=0.01) in the FGF2 was associated with ossification of the ligament flavum (OLF). CONCLUSION: The results of the present study revealed that an FGFR1 SNP was significantly associated with OPLL and that a SNP in FGF2 was associated with conditions that were comorbid with OPLL (DISH and OLF).


Subject(s)
Humans , Case-Control Studies , Fibroblast Growth Factor 2 , Fibroblast Growth Factors , Fibroblasts , Hyperostosis, Diffuse Idiopathic Skeletal , Ligaments , Longitudinal Ligaments , Polymorphism, Single Nucleotide , Receptors, Fibroblast Growth Factor , Receptors, Growth Factor
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