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1.
Curr Stem Cell Res Ther ; 19(7): 1009-1020, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38221663

RESUMO

BACKGROUND: This systematic review describes the most common methodologies for immortalizing human and animal mesenchymal stem cells (MSCs). This study follows the rules of PRISMA and is registered in the Institutional Review Board of PROSPERO International of systematic reviews, numbered protocol code: CRD42020202465. METHOD: The data search systematization was based on the words "mesenchymal stem cell" AND "immortalization." The search period for publications was between 2000 and 2022, and the databases used were SCOPUS, PUBMED, and SCIENCE DIRECT. The search strategies identified 384 articles: 229 in the SCOPUS database, 84 in PUBMED, and 71 in SCIENCE DIRECT. After screening by titles and abstracts, 285 articles remained. This review included thirty-nine articles according to the inclusion and exclusion criteria. RESULT: In 28 articles, MSCs were immortalized from humans and 11 animals. The most used immortalization methodology was viral transfection. The most common immortalized cell type was the MSC from bone marrow, and the most used gene for immortalizing human and animal MSCs was hTERT (39.3%) and SV40T (54.5%), respectively. CONCLUSION: Also, it was observed that although less than half of the studies performed tumorigenicity assays to validate the immortalized MSCs, other assays, such as qRT-PCR, colony formation in soft agar, karyotype, FISH, and cell proliferation, were performed in most studies on distinct MSC cell passages.


Assuntos
Células-Tronco Mesenquimais , Medicina Regenerativa , Células-Tronco Mesenquimais/citologia , Humanos , Medicina Regenerativa/métodos , Animais , Telomerase/metabolismo , Telomerase/genética
2.
Oncol Rep ; 49(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36960859

RESUMO

PIN1 is the only known enzyme capable of recognizing and isomerizing the phosphorylated Serine/Threonine­Proline motif. Through this mechanism, PIN1 controls diverse cellular functions, including telomere maintenance. Both PIN1 overexpression and its involvement in oncogenic pathways are involved in several cancer types, including glioblastoma (GBM), a lethal disease with poor therapeutic resources. However, knowledge of the role of PIN1 in GBM is limited. Thus, the present work aimed to study the role of PIN1 as a telomere/telomerase regulator and its contribution to tumor biology. PIN1 knockout (KO) LN­229 cell variant using CRISPR/Cas9 was developed and compared with PIN1 LN­229 expressing cells. To study the effect of PIN1 absence, status of NF­κB pathway was evaluated by luciferase reporter gene assay and quantitative PCR. Results revealed that PIN1 deletion in GBM cells diminished the active levels of NF­κB and decrease the transcription of il­8 and htert genes. Then, telomere/telomerase related processes were studied by RQ­TRAP assay and telomere length determination by qPCR, obtaining a reduction both in telomerase activity as in telomere length in PIN1 KO cells. In addition, measurement of SA ß­galactosidase and caspase­3 activities revealed that loss of PIN1 triggers senescence and apoptosis. Finally, migration, cell cycle progression and tumorigenicity were studied by flow cytometry/western blot, Transwell assay and in vivo experiments, respectively. PIN1 deletion decreased migration as well as cell cycle progression by increasing doubling time and also resulted in the loss of LN­229 cell ability to form tumors in mice. These results highlight the role of PIN1 in telomere homeostasis and GBM progression, which supports PIN1 as a potential molecular target for the development of novel therapeutic agents for GBM treatment.


Assuntos
Glioblastoma , Telomerase , Humanos , Animais , Camundongos , Glioblastoma/patologia , NF-kappa B/genética , NF-kappa B/metabolismo , Telomerase/metabolismo , Reação em Cadeia da Polimerase , Telômero/genética , Telômero/metabolismo , Linhagem Celular Tumoral , Peptidilprolil Isomerase de Interação com NIMA/genética , Peptidilprolil Isomerase de Interação com NIMA/metabolismo
3.
Clin Transl Oncol ; 22(9): 1619-1634, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32056127

RESUMO

BACKGROUND: Mammospheres are breast cancer stem cells (BCSCs) that could be yielded through culturing cells in non-adherent and non-differentiating condition. With regard to therapy resistance of cancer stem cells (CSCs), it is essential to discover efficient approaches targeting CSCs. Viola odorata extract has been considered as a traditional herbal anti-metastatic drug in several cancer cells. Effect of this drug on BCSCs has not been clearly identified. Current study tries to detect and to compare effect of Viola odorata extract on malignant characterization of breast cancer cell lines and BCSCs. MATERIALS AND METHODS: MCF7 and SKBR3 and their derived mammospheres as BCSCs were used and the effect of alcoholic extraction of Viola odorata on apoptosis and malignant characters of MCF7, SKBR3 and their derived BCSCs were analyzed and compared. RESULTS: Viola odorata extract induced cell death in MCF7, SKBR3 and their derived mammospheres through apoptosis without any effects on MCF10A. Also, this extract showed anti-migratory, anti-invasion and anti-colony formation activity in MCF7, SKBR3 and their derived mammospheres which was significantly more in MCF7- and SKBR3-derived mammospheres. Also, this extract decreased size and volume of tumors generated by MCF7, SKBR3 and their derived mammospheres in chicken embryo model. CONCLUSION: Viola odorata extract exerted anti-cancerous activity on both breast cancer cell lines and their derived BCSCs. Anti-cancerous activity of this extract was significantly more in MCF7-, SKBR3-derived mammospheres in comparison with dedicated cell lines. Data suggest that Viola odorata extract mostly targets cancerous cells, not normal cells with exception in high concentration. It acts in a cell-dependent manner.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Viola/química , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Feminino , Humanos , Células-Tronco Neoplásicas/patologia , Esferoides Celulares
4.
Cytokine ; 127: 154965, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31901762

RESUMO

BACKGROUND: Mechanisms influencing severity of acute lower respiratory infection (ALRI) in children are not established. We aimed to assess the role of inflammatory markers and respiratory viruses in ALRI severity. METHODS: Concentrations of interleukin(IL)-33, soluble suppression of tumorigenicity (sST)2, IL-1ß, tumor necrosis factor α, IL-4, IL-6 and IL- 8 and types of respiratory viruses were evaluated in children at the first and fifth days after hospital admission. Disease severity was defined as need for mechanical ventilation. RESULTS: Seventy-nine children <5 years-old were included; 33(41.8%) received mechanical ventilation. No associations between virus type, viral load or co-detections and severity of disease were observed. Detection of IL-33 and sST2 in nasopharyngeal aspirates (NPA) on admission were associated with higher risk for mechanical ventilation (RR = 2.89 and RR = 4.57, respectively). IL-6 and IL-8 concentrations were higher on Day 5 in mechanically ventilated children. IL-6 NPA concentrations decreased from Day 1 to Day 5 in children who did not receive mechanical ventilation. Increase in sST2 NPA concentrations from Day 1 to Day 5 was associated with longer hospital length of stay (p < 0.01). CONCLUSIONS: An exacerbated local activation of the IL-33/ST2 axis and persistently high sST2 concentrations over time were associated with severity of viral ALRI in children.


Assuntos
Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Interleucina-33/metabolismo , Infecções por Vírus Respiratório Sincicial/metabolismo , Infecções por Vírus Respiratório Sincicial/patologia , Infecções Respiratórias/metabolismo , Infecções Respiratórias/patologia , Biomarcadores/metabolismo , Pré-Escolar , Feminino , Hospitalização , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença
5.
Clin Transl Oncol ; 21(7): 910-923, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30565087

RESUMO

OBJECTIVES: Citron kinase (CIT-K), as a key Rho effector, functions to maintain proper structure of the midbody during cell mitosis. This study assessed CIT-K expression and its role in breast cancer cells. METHODS: Paraffin-embedded breast cancer and para-tumor tissues from 43 invasive breast cancer patients and 33 normal mammary glands were collected for immunohistochemistry. CIT-K expression knockdown was achieved using lentivirus carrying CIT-K shRNA in a wide range of breast cancer cell lines. Cells were then subjected to Western blot, qRT-PCR, cell proliferation, colony formation, transwell, and flow cytometric assays. The tumorigenicity of CIT-K knocked-down breast cancer cells was assessed using the nude mouse xenograft assay. Microarray analysis was performed to elucidate the underlying gene regulation after CIT-K silencing. RESULTS: CIT-K protein was overexpressed in breast cancer tissues, which is associated with advanced tumor stage, HER-2 expression and Ki-67 expression, whereas knockdown of CIT-K expression reduced breast cancer cell proliferation and colony formation, but promoted tumor cell apoptosis and cell-cycle arrest. Knockdown of CIT-K expression also inhibited breast cancer cell migration and invasion capacity. Moreover, CIT-K knockdown suppressed the tumorigenicity of breast cancer cells in nude mice. Molecularly, the expression of a variety of signaling genes, such as cyclin D1, EGFR, JAK1, TGF-α, PTK2, RAF1, RALB, SOS1, mTOR, and PTGS2, were altered after CIT-K knockdown. CONCLUSIONS: This study demonstrated that CIT-K is associated with aggressive breast cancer behavior and targeting CIT-K may be a novel strategy for the future control of breast cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Transformação Celular Neoplásica/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Ciclo Celular , Movimento Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Vet Comp Oncol ; 16(4): 596-605, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30047225

RESUMO

Mammary tumours are the most frequent in female dogs as in women and half are malignant. Tumorigenicity and invasiveness are important acquired characteristics for the development and progression of cancers and could be regulated by transcription factors associated with epithelial-mesenchymal transition (EMT) as ZEB1, ZEB2, SNAI1, SLUG and STAT3. Thus, here, we evaluate the expression of EMT-associated transcription factors in canine mammary cancer (CMC) cell lines characterized for invasiveness and tumorigenicity to determine if these could be considered good targets for future development of therapies. Five CMC cell lines were characterized regarding their morphology, doubling time and expression of intermediate and actin filaments. In addition, gene expression of SLUG, STAT3, ZEB1, ZEB2 and CDH1, tumorigenicity and invasiveness were assessed. Two of these cells presented an epithelial-like morphology (E20 and E37) and three a mesenchymal-like morphology (M5, M25 and CF41.Mg). M25 and CF41.Mg presented higher invasiveness. Furthermore, only mesenchymal-like cells formed tumorspheres and CF41.Mg made more and larger tumorspheres. The mesenchymal-like cells are more malignant than the epithelial-like cells being the CF41.Mg the most malignant. This cell presented higher ZEB1 and ZEB2 and lower CDH1 gene expression. Finally, our results revealed that there is a positive correlation between ZEBs and the tumorsphere number and size. In conclusion, these findings support ZEB1 and ZEB2 as potential therapeutic targets for CMC cells, demonstrating a great potential of canine models for comparative and translational studies.


Assuntos
Doenças do Cão/metabolismo , Neoplasias Mamárias Animais/metabolismo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Actinas/metabolismo , Animais , Western Blotting/veterinária , Linhagem Celular Tumoral , Doenças do Cão/patologia , Cães , Feminino , Regulação Neoplásica da Expressão Gênica , Neoplasias Mamárias Animais/patologia , Invasividade Neoplásica , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Fator de Transcrição STAT3/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição da Família Snail/metabolismo
7.
Biol Res ; 51(1): 16, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29880026

RESUMO

BACKGROUND: Stathmin as a critical protein involved in microtubule polymerization, is necessary for survival of cancer cells. However, extremely little is known about Stathmin in glioblastoma. So, this study was designed to elucidate the function of Stathmin gene in the tumorigenesis and progression of glioblastoma cells. METHOD: The lentiviral interference vector pLV3-si-Stathmin targeting Stathmin gene and the control vector pLV3-NC were established for the co-transfection of 293T cells together with the helper plasmids. Viral titer was determined via limiting dilution assay. Then pLV3-si-Stathmin and pLV3-NC were stably co-transfected into U373 and U87-MG glioblastoma cells. Expression levels of Stathmin protein in each group were determined by using Western Blot, and the proliferation and migration ability of the cells with downregulated Stathmin were evaluated through CCK8 assay and transwell invasion assay, respectively. Cell cycles and cell apoptosis were detected with flow cytometry. Finally, the effect of Stathmin in tumor formation was determined in nude mice. RESULT: DNA sequencing and viral titer assay indicated that the lentiviral interference vector was successfully established with a viral titer of 4 × 108 TU/ml. According to the results from Western Blotting, Stathmin protein expression level decreased significantly in the U373 and U87-MG cells after transfected with pLV3-si-Stathmin, respectively, compared with those transfected with pLV3-NC. In glioblastoma cells, the cell proliferation and migration were greatly inhibited after the downregulation of Stathmin protein. Flow cytometry showed that much more cells were arrested in G2/M phasein Stathmin downregulated group, compared with the non-transfection group and NC group. But Stathmin downregulation did not induce significant cell apoptosis. Tumor formation assay in nude mice showed that tumor formation was delayed after Stathmin downregulation, with a reduction in both tumor formation rate and tumor growth velocity. CONCLUSION: Stathmin downregulation affected the biological behaviors of U373 and U87-MG glioblastoma cells, inhibiting the proliferation and migration of tumor cells. Stathmin gene may serve as a potential target in gene therapy for glioblastoma.


Assuntos
Proliferação de Células/genética , Regulação para Baixo/genética , Glioblastoma/metabolismo , Estatmina/genética , Animais , Linhagem Celular Tumoral , Vetores Genéticos , Glioblastoma/genética , Glioblastoma/patologia , Camundongos , Estatmina/metabolismo , Transfecção
8.
Biol. Res ; 51: 16, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-950902

RESUMO

BACKGROUND: Stathmin as a critical protein involved in microtubule polymerization, is necessary for survival of cancer cells. However, extremely little is known about Stathmin in glioblastoma. So, this study was designed to elucidate the function of Stathmin gene in the tumorigenesis and progression of glioblastoma cells. METHOD: The lentiviral interference vector pLV3-si-Stathmin targeting Stathmin gene and the control vector pLV3-NC were established for the co-transfection of 293T cells together with the helper plasmids. Viral titer was determined via limiting dilution assay. Then pLV3-si-Stathmin and pLV3-NC were stably co-transfected into U373 and U87-MG glioblastoma cells. Expression levels of Stathmin protein in each group were determined by using Western Blot, and the proliferation and migration ability of the cells with downregulated Stathmin were evaluated through CCK8 assay and transwell invasion assay, respectively. Cell cycles and cell apoptosis were detected with flow cytometry. Finally, the effect of Stathmin in tumor formation was determined in nude mice. RESULT: DNA sequencing and viral titer assay indicated that the lentiviral interference vector was successfully established with a viral titer of 4 × 108 TU/ml. According to the results from Western Blotting, Stathmin protein expression level decreased significantly in the U373 and U87-MG cells after transfected with pLV3-si-Stathmin, respectively, compared with those transfected with pLV3-NC. In glioblastoma cells, the cell proliferation and migration were greatly inhibited after the downregulation of Stathmin protein. Flow cytometry showed that much more cells were arrested in G2/M phasein Stathmin downregulated group, compared with the non-transfection group and NC group. But Stathmin downregulation did not induce significant cell apoptosis. Tumor formation assay in nude mice showed that tumor formation was delayed after Stathmin downregulation, with a reduction in both tumor formation rate and tumor growth velocity. CONCLUSION: Stathmin downregulation affected the biological behaviors of U373 and U87-MG glioblastoma cells, inhibiting the proliferation and migration of tumor cells. Stathmin gene may serve as a potential target in gene therapy for glioblastoma.


Assuntos
Animais , Camundongos , Regulação para Baixo/genética , Glioblastoma/metabolismo , Proliferação de Células/genética , Estatmina/genética , Transfecção , Glioblastoma/genética , Glioblastoma/patologia , Linhagem Celular Tumoral , Estatmina/metabolismo , Vetores Genéticos
9.
Int J Clin Exp Pathol ; 7(9): 5515-26, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25337193

RESUMO

Smac-α is a mitochondrial protein that, during apoptosis, is translocated to the cytoplasm, where it negatively regulates members of the inhibitor of apoptosis (IAP) family via the IAP-binding motif (IBM) contained within its amino-terminus. Here, we describe a new alternative splice variant from Smac gene, which we have named Smac-ε. Smac-ε lacks both an IBM and a mitochondrial-targeting signal (MTS) element. Smac-ε mRNA exhibits a tissue-specific expression pattern in healthy human tissues as well as in several cancer cell lines. The steady-state levels of endogenous Smac-ε protein is regulated by the proteasomal pathway. When ectopically expressed, this isoform presents a cytosolic localization and is unable to associate with or to regulate the expression of X-linked Inhibitor of apoptosis protein, the best-studied member of IAP family. Nevertheless, over-expression of Smac-ε increases mammosphere formation. Whole genome expression analyses from these mammospheres show activation of several pro-survival and growth pathways, including Estrogen-Receptor signaling. In conclusion, our results support the functionality of this new Smac isoform.


Assuntos
Neoplasias da Mama/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Reguladoras de Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Citosol/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células MCF-7 , Proteínas Mitocondriais/genética , Análise de Sequência com Séries de Oligonucleotídeos , Complexo de Endopeptidases do Proteassoma/metabolismo , Isoformas de Proteínas , Proteólise , Esferoides Celulares , Transcrição Gênica , Transfecção , Regulação para Cima
10.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;45(3): 197-204, Mar. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-618047

RESUMO

Our group established a method to culture spheres under serum-free culture condition. However, the biological characteristics and the tumorigenicity of spheres are unknown. Here, we demonstrate that sphere cells expressed high levels of the putative colorectal cancer stem cell markers CD133 and CD44. The CD133-positive rates were 13.27 ± 5.62, 52.71 ± 16.97 and 16.47 ± 2.45 percent in sphere cells, regular Colo205 cells and differentiated sphere cells, respectively, while the CD44-positive rates were 62.92 ± 8.38, 79.06 ± 12.10 and 47.80 ± 2.5 percent, respectively, and the CD133/CD44-double-positive rates were 10.77 ± 4.96, 46.89 ± 19.17 and 12.41 ± 2.27 percent, respectively (P < 0.05). Cancer sphere cells formed crypt-like structures in 3-D culture. Moreover, cells from cancer spheres exhibited more tumorigenicity than regular Colo205 cells in a xenograft assay. The cancer sphere cells displayed much higher oncogenicity than regular Colo205 cells to initiate neoplasms, as assayed by H&E staining, Musashi-1 staining and electron microscopy. Our findings indicated that the sphere cells were enriched with cancer stem cells (CSCs), and exhibited more proliferation capacity, more differentiation potential and especially more tumorigenicity than regular Colo205 cells in vitro and in vivo. Further isolation and characterization of these CSCs may provide new insights for novel therapeutic targets and prognostic markers.


Assuntos
Animais , Humanos , Camundongos , Antígenos CD/metabolismo , /metabolismo , Proliferação de Células , Neoplasias do Colo/patologia , Glicoproteínas/metabolismo , Células-Tronco Neoplásicas/patologia , Peptídeos/metabolismo , Esferoides Celulares/patologia , Biomarcadores Tumorais , Linhagem Celular Tumoral , Técnicas de Cultura de Células/métodos , Neoplasias do Colo/metabolismo , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Esferoides Celulares/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;45(2): 97-103, Feb. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-614568

RESUMO

The biological functions of the BC047440 gene highly expressed by hepatocellular carcinoma (HCC) are unknown. The objective of this study was to reconstruct antisense eukaryotic expression vectors of the gene for inhibiting HepG2 cell proliferation and suppressing their xenograft tumorigenicity. The full-length BC047440 cDNA was cloned from human primary HCC by RT-PCR. BC047440 gene fragments were ligated with pMD18-T simple vectors and subsequent pcDNA3.1(+) plasmids to construct the recombinant antisense eukaryotic vector pcDNA3.1(+)BC047440AS. The endogenous BC047440 mRNA abundance in target gene-transfected, vector-transfected and naive HepG2 cells was semiquantitatively analyzed by RT-PCR and cell proliferation was measured by the MTT assay. Cell cycle distribution and apoptosis were profiled by flow cytometry. The in vivo xenograft experiment was performed on nude mice to examine the effects of antisense vector on tumorigenicity. BC047440 cDNA fragments were reversely inserted into pcDNA3.1(+) plasmids. The antisense vector significantly reduced the endogenous BC047440 mRNA abundance by 41 percent in HepG2 cells and inhibited their proliferation in vitro (P < 0.01). More cells were arrested by the antisense vector at the G1 phase in an apoptosis-independent manner (P = 0.014). Additionally, transfection with pcDNA3.1(+)BC047440AS significantly reduced the xenograft tumorigenicity in nude mice. As a novel cell cycle regulator associated with HCC, the BC047440 gene was involved in cell proliferation in vitro and xenograft tumorigenicity in vivo through apoptosis-independent mechanisms.


Assuntos
Animais , Humanos , Camundongos , Carcinoma Hepatocelular/metabolismo , DNA Antissenso/genética , Expressão Gênica , Vetores Genéticos/genética , Proliferação de Células , DNA Antissenso/metabolismo , Células Eucarióticas/metabolismo , Citometria de Fluxo , Vetores Genéticos/metabolismo , /metabolismo , Camundongos Nus , Transplante de Neoplasias , Plasmídeos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Mensageiro/análise , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Rev. bras. farmacogn ; 21(6): 1025-1034, Nov.-Dec. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-602300

RESUMO

This study aimed to investigate the antitumorigenicity of xanthones-rich extract from Garcinia mangostana L., Clusiaceae, fruit rinds which was obtained by a simple recrystallization of 75 percent ethanolic extract. α-Mangostin content of the extract was determined qualitatively by TLC and quantitatively by HPLC, and total xanthones content was quantified by UV spectrophotometry. The extract was evaluated for cytotoxicity, apoptosis and antitumorigenicity on HCT 116 human colorectal carcinoma cells. α-Mangostin was found to be the main constituent of the extract which was 71.2±0.1 percent, and the total xanthones content was 95±4.8 percent (wt/wt). The extract showed potent dose dependent cytotoxicity with IC50 value 9.2 μg/mL. Apoptosis studies revealed activation of caspases 3 and 7, DNA fragmentation, chromatin condensation and loss of mitochondrial membrane potential. Studies on cell migration and colony formation indicate reduced cell migration ability and clonogenicity of treated HCT 116 cells at sub-inhibitory concentrations. Taken together, the cytotoxic effect of the xanthones extract is mediated through the mitochondrial pathway of apoptosis. The reduced cell migration and clonogenicity of HCT 116 cells might prevent both primary and metastatic tumor growth in vivo which will be the topic of our future work using the metastatic orthotopic colon cancer model.

13.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;41(2): 110-116, Feb. 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-474763

RESUMO

To find Epstein-Barr virus (EBV) strains with genetic variations of EBV latent membrane protein 1 (EBV-LMP1) from nasopharyngeal carcinoma (NPC), the full-length DNA of LMP1 genes from 21 NPC biopsies obtained in Hunan province in southern China was amplified and sequenced. Our sequences were compared to those previously reported by the Clustal V method. Results showed that all 21 sequences displayed two amino acid changes most frequently in LMP1 of CD4+ T cell epitopes at codons 144 (F arrow right I, 21/21) and 212 (G arrow right S, 19/21) or (G arrow right N, 2/21). We also show that type A EBV strain is prevalent in the cases of NPC from Hunan province with a 30-bp 18/21 deletion, and we highlight that this deletion resulted in loss of one of the CD4+ T cell-restricted epitopes. The other 3 sequences without this deletion all had a change at codon 344 (G arrow right D). Furthermore, in the major epitope sequence of CD8+ T cells restricted by HLA-A2, all 21 sequences showed changes at codons 126 (L arrow right F) and 129 (M arrow right I). Our study discovered that one of the 21 sequence variations harbored a new change at codon 131 (W arrow right C), and 5/21 specimens showed another novel change at codon 115 (G arrow right A) in the major epitope sequence of CD8+ T cells restricted by HLA-A2. Our study suggests that these sequence variations of NPC-derived LMP1 may lead to a potential escape from host cell immune recognition, protecting latent EBV infection and causing an increase in tumorigenicity.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Epitopos de Linfócito T/genética , Variação Genética , /genética , Neoplasias Nasofaríngeas/virologia , Proteínas da Matriz Viral/genética , Sequência de Aminoácidos , Biópsia , Epitopos de Linfócito T/análise , Genótipo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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