MiR-30e-5p overexpression promotes proliferation and migration of colorectal cancer cells by activating the CXCL12 axis via downregulating PTEN / 南方医科大学学报

OBJECTIVE@#To investigate the regulatory effects of miR-30e-5p on biological behaviors of colorectal cancer cells and the role of PTEN/CXCL12 axis in mediating these effects.@*METHODS@#Bioinformatic analysis was performed to explore the differential expression of miR-30e-5p between colorectal cancer tissues and normal tissues. RT-qPCR was used to detect the differential expression of miR-30e-5p in intestinal epithelial cells and colorectal cancer cells. Bioinformatics and dual luciferase assay were used to predict and validate the targeting relationship between miR-30e-5p and PTEN. Human and murine colorectal cancer cell lines were transfected with miR-30e-5p mimics, miR-30e-5p inhibitor, miR-30e-5p mimics+LV-PTEN, or miR-30e-5p inhibitor + si-PTEN. The changes in biological behaviors of the cells were detected using plate clone formation assay, CCK-8 assay, flow cytometry, scratch healing and Transwell assays. PTEN and CXCL12 expressions in the cancer cells were detected by Western blotting. The effects of miR-30e-5p inhibitor on colorectal carcinogenesis and development were observed in nude mice.@*RESULTS@#Bioinformatic analysis showed that miR-30e-5p expression was significantly elevated in colorectal cancer tissues compared with the adjacent tissue (P < 0.01). Higher miR-30e-5p expression was detected in colorectal cancer cell lines than in intestinal epithelial cells (P < 0.01). Dual luciferase assay confirmed the targeting relationship between miR-30e-5p and PTEN (P < 0.05). Transfection with miR-30e-5p mimics significantly enhanced proliferation and metastasis and inhibited apoptosis of the colorectal cancer cells (P < 0.05), and co-transfection with LV-PTEN obviously reversed these changes (P < 0.05). MiR-30e-5p mimics significantly inhibited PTEN expression and enhanced CXCL12 expression in the cancer cells (P < 0.01), and miR-30e-5p inhibitor produced the opposite effect. Transfection with miR-30e-5p inhibitor caused cell cycle arrest in the cancer cells, which was reversed by co-transfection with si-PTEN (P < 0.05). In the in vivo experiments, the colorectal cancer cells transfected with miR-30e-5p inhibitor showed significantly lowered tumorigenesis.@*CONCLUSION@#Overexpression of miR-30e-5p promotes the malignant behaviors of colorectal cancer cells by downregulating PTEN to activate the CXCL12 axis.

Electrotaxis of alveolar epithelial cells in direct-current electric fields / 中华创伤杂志(英文版)

PURPOSE@#This study aims to elucidate the electrotaxis response of alveolar epithelial cells (AECs) in direct-current electric fields (EFs), explore the impact of EFs on the cell fate of AECs, and lay the foundation for future exploitation of EFs for the treatment of acute lung injury.@*METHODS@#AECs were extracted from rat lung tissues using magnetic-activated cell sorting. To elucidate the electrotaxis responses of AECs, different voltages of EFs (0, 50, 100, and 200 mV/mm) were applied to two types of AECs, respectively. Cell migrations were recorded and trajectories were pooled to better demonstrate cellular activities through graphs. Cell directionality was calculated as the cosine value of the angle formed by the EF vector and cell migration. To further demonstrate the impact of EFs on the pulmonary tissue, the human bronchial epithelial cells transformed with Ad12-SV40 2B (BEAS-2B cells) were obtained and experimented under the same conditions as AECs. To determine the influence on cell fate, cells underwent electric stimulation were collected to perform Western blot analysis.@*RESULTS@#The successful separation and culturing of AECs were confirmed through immunofluorescence staining. Compared with the control, AECs in EFs demonstrated a significant directionality in a voltage-dependent way. In general, type Ⅰ alveolar epithelial cells migrated faster than type Ⅱ alveolar epithelial cells, and under EFs, these two types of cells exhibited different response threshold. For type Ⅱ alveolar epithelial cells, only EFs at 200 mV/mm resulted a significant difference to the velocity, whereas for, EFs at both 100 mV/mm and 200 mV/mm gave rise to a significant difference. Western blotting suggested that EFs led to an increased expression of a AKT and myeloid leukemia 1 and a decreased expression of Bcl-2-associated X protein and Bcl-2-like protein 11.@*CONCLUSION@#EFs could guide and accelerate the directional migration of AECs and exert antiapoptotic effects, which indicated that EFs are important biophysical signals in the re-epithelialization of alveolar epithelium in lung injury.

Regulatory effects of bio-intensity electric field on transformation of human skin fibroblasts / 中华烧伤杂志

Objective: To investigate the regulatory effects of bio-intensity electric field on the transformation of human skin fibroblasts (HSFs). Methods: The experimental research methods were used. HSFs were collected and divided into 200 mV/mm electric field group treated with 200 mV/mm electric field for 6 h and simulated electric field group placed in the electric field device without electricity for 6 h. Changes in morphology and arrangement of cells were observed in the living cell workstation; the number of cells at 0 and 6 h of treatment was recorded, and the rate of change in cell number was calculated; the direction of cell movement, movement velocity, and trajectory velocity within 3 h were observed and calculated (the number of samples was 34 in the simulated electric field group and 30 in 200 mV/mm electric field group in the aforementioned experiments); the protein expression of α-smooth muscle actin (α-SMA) in cells after 3 h of treatment was detected by immunofluorescence method (the number of sample was 3). HSFs were collected and divided into simulated electric field group placed in the electric field device without electricity for 3 h, and 100 mV/mm electric field group, 200 mV/mm electric field group, and 400 mV/mm electric field group which were treated with electric fields of corresponding intensities for 3 h. Besides, HSFs were divided into simulated electric field group placed in the electric field device without electricity for 6 h, and electric field treatment 1 h group, electric field treatment 3 h group, and electric field treatment 6 h group treated with 200 mV/mm electric field for corresponding time. The protein expressions of α-SMA and proliferating cell nuclear antigen (PCNA) were detected by Western blotting (the number of sample was 3). Data were statistically analyzed with Mann-Whitney U test, one-way analysis of variance, independent sample t test, and least significant difference test. Results: After 6 h of treatment, compared with that in simulated electric field group, the cells in 200 mV/mm electric field group were elongated in shape and locally adhered; the cells in simulated electric field group were randomly arranged, while the cells in 200 mV/mm electric field group were arranged in a regular longitudinal direction; the change rates in the number of cells in the two groups were similar (P>0.05). Within 3 h of treatment, the cells in 200 mV/mm electric field group had an obvious tendency to move toward the positive electrode, and the cells in simulated electric field group moved around the origin; compared with those in simulated electric field group, the movement velocity and trajectory velocity of the cells in 200 mV/mm electric field group were increased significantly (with Z values of -5.33 and -5.41, respectively, P<0.01), and the directionality was significantly enhanced (Z=-4.39, P<0.01). After 3 h of treatment, the protein expression of α-SMA of cells in 200 mV/mm electric field group was significantly higher than that in simulated electric field group (t=-9.81, P<0.01). After 3 h of treatment, the protein expressions of α-SMA of cells in 100 mV/mm electric field group, 200 mV/mm electric field group, and 400 mV/mm electric field group were 1.195±0.057, 1.606±0.041, and 1.616±0.039, respectively, which were significantly more than 0.649±0.028 in simulated electric field group (P<0.01). Compared with that in 100 mV/mm electric field group, the protein expressions of α-SMA of cells in 200 mV/mm electric field group and 400 mV/mm electric field group were significantly increased (P<0.01). The protein expressions of α-SMA of cells in electric field treatment 1 h group, electric field treatment 3 h group, and electric field treatment 6 h group were 0.730±0.032, 1.561±0.031, and 1.553±0.045, respectively, significantly more than 0.464±0.020 in simulated electric field group (P<0.01). Compared with that in electric field treatment 1 h group, the protein expressions of α-SMA in electric field treatment 3 h group and electric field treatment 6 h group were significantly increased (P<0.01). After 3 h of treatment, compared with that in simulated electric field group, the protein expressions of PCNA of cells in 100 mV/mm electric field group, 200 mV/mm electric field group, and 400 mV/mm electric field group were significantly decreased (P<0.05 or P<0.01); compared with that in 100 mV/mm electric field group, the protein expressions of PCNA of cells in 200 mV/mm electric field group and 400 mV/mm electric field group were significantly decreased (P<0.05 or P<0.01); compared with that in 200 mV/mm electric field group, the protein expression of PCNA of cells in 400 mV/mm electric field group was significantly decreased (P<0.01). Compared with that in simulated electric field group, the protein expressions of PCNA of cells in electric field treatment 1 h group, electric field treatment 3 h group, and electric field treatment 6 h group were significantly decreased (P<0.01); compared with that in electric field treatment 1 h group, the protein expressions of PCNA of cells in electric field treatment 3 h group and electric field treatment 6 h group were significantly decreased (P<0.05 or P<0.01); compared with that in electric field treatment 3 h group, the protein expression of PCNA of cells in electric field treatment 6 h group was significantly decreased (P<0.01). Conclusions: The bio-intensity electric field can induce the migration of HSFs and promote the transformation of fibroblasts to myofibroblasts, and the transformation displays certain dependence on the time and intensity of electric field.

Effect of lncRNA HULC knockdown on rat secreting pituitary adenoma GH3 cells

Pituitary adenoma is one of the most common tumors in the neuroendocrine system. This study investigated the effects of long non-coding RNAs (lncRNAs) highly up-regulated in liver cancer (HULC) on rat secreting pituitary adenoma GH3 cell viability, migration, invasion, apoptosis, and hormone secretion, as well as the underlying potential mechanisms. Cell transfection and qRT-PCR were used to change and measure the expression levels of HULC, miR-130b, and FOXM1. Cell viability, migration, invasion, and apoptosis were assessed using trypan blue staining assay, MTT assay, two-chamber transwell assay, Guava Nexin assay, and western blotting. The concentrations of prolactin (PRL) and growth hormone (GH) in culture supernatant of GH3 cells were assessed using ELISA. The targeting relationship between miR-130b and FOXM1 was verified using dual luciferase activity. Finally, the expression levels of key factors involved in PI3K/AKT/mTOR and JAK1/STAT3 pathways were evaluated using western blotting. We found that HULC was highly expressed in GH3 cells. Overexpression of HULC promoted GH3 cell viability, migration, invasion, PRL and GH secretion, as well as activated PI3K/AKT/mTOR and JAK1/STAT3 pathways. Knockdown of HULC had opposite effects and induced cell apoptosis. HULC negatively regulated the expression of miR-130b, and miR-130b participated in the effects of HULC on GH3 cells. FOXM1 was a target gene of miR-130b, which was involved in the regulation of GH3 cell viability, migration, invasion, and apoptosis, as well as PI3K/AKT/mTOR and JAK1/STAT3 pathways. In conclusion, HULC tumor-promoting roles in secreting pituitary adenoma might be via down-regulating miR-130b, up-regulating FOXM1, and activating PI3K/AKT/mTOR and JAK1/STAT3 pathways.

FOXC2-AS1 regulates phenotypic transition, proliferation and migration of human great saphenous vein smooth muscle cells

OBJECTIVES: In varicose veins, vascular smooth muscle cells (VSMCs) often shows phenotypic transition and abnormal proliferation and migration. Evidence suggests the FOXC2-Notch pathway may be involved in the pathogenesis of varicose veins. Here, this study aimed to explore the role of long non-coding RNA FOXC2-AS1 (FOXC2 antisense RNA 1) in phenotypic transition, proliferation, and migration of varicose vein-derived VSMCs and to explore whether the FOXC2-Notch pathway was involved in this process. METHODS: The effect of FOXC2-AS1 on the proliferation and migration of human great saphenous vein smooth muscle cells (SV-SMCs) was analyzed using MTT assay and Transwell migration assay, respectively. The levels of contractile marker SM22α and synthetic marker osteopontin were measured by immunohistochemistry and Western blot to assess the phenotypic transition. RESULTS: The human varicose veins showed thickened intima, media and adventitia layers, increased synthetic VSMCs, as well as upregulated FOXC2-AS1 and FOXC2 expression. In vitro assays showed that FOXC2-AS1 overexpression promoted phenotypic transition, proliferation, and migration of SV-SMCs. However, the effect of FOXC2-AS1 overexpression could be abrogated by both FOXC2 silencing and the Notch signaling inhibitor FLI-06. Furthermore, FOXC2-AS1 overexpression activated the Notch pathway by upregulating FOXC2. CONCLUSION: FOXC2-AS1 overexpression promotes phenotypic transition, proliferation, and migration of SV-SMCs, at least partially, by activating the FOXC2-Notch pathway.

Alternagin-C binding to 21 integrin controls matrix metalloprotease-9 and matrix metalloprotease-2 in breast tumor cells and endothelial cells

Background Matrix metalloproteinases (MMPs) are key players in tumor progression, helping tumor cells to modify their microenvironment, which allows cell migration to secondary sites. The role of integrins, adhesion receptors that connect cells to the extracellular matrix, in MMP expression and activity has been previously suggested. However, the mechanisms by which integrins control MMP expression are not completely understood. Particularly, the role of 21 integrin, one of the major collagen I receptors, in MMP activity and expression has not been studied. Alternagin-C (ALT-C), a glutamate-cysteine-aspartate-disintegrin from Bothrops alternatus venom, has high affinity for an 21 integrin. Herein, we used ALT-C as a 21 integrin ligand to study the effect of ALT-C on MMP-9 and MMP-2 expression as well as on tumor cells, fibroblats and endothelial cell migration. Methods ALT-C was purified by two steps of gel filtration followed by anion exchange chromatography. The 21, integrin binding properties of ALT-C, its dissociation constant (Kd) relative to this integrin and to collagen I (Col I) were determined by surface plasmon resonance. The effects of ALT-C (10, 40, 100 and 1000 nM) in migration assays were studied using three human cell lines: human fibroblasts, breast tumor cell line MDA-MB-231, and microvascular endothelial cells HMEC-1, considering cells found in the tumor microenvironment. ALT-C effects on MMP-9 and MMP-2 expression and activity were analyzed by quantitative PCR and gelatin zymography, respectively. Focal adhesion kinase activation was determined by western blotting. Results Our data demonstrate that ALT-C, after binding to 21 integrin...

Role of the CHD7 chromatin remodeler protein in glioblastoma multiformePalavras-chave em inglês Cell motility / Papel do remodelador de cromatina CHD7 em glioblastoma multiforme

Chromatin remodeler proteins exert an important function in promoting dynamic modifications in the chromatin architecture, rendering the transcriptional machinery available to the condensed genomic DNA. Due to this central role in regulating gene transcription, deregulation of these molecular machines may lead to severe perturbations in the normal cell functions. Loss-of-function mutations in the CHD7 gene, a member of the chromodomain helicase DNA-binding (CHD) family, are the major cause of the CHARGE syndrome in humans. The disease is characterized by a variety of congenital anomalies, including malformations of the craniofacial structures, peripheral nervous system, ears, eyes and heart. In this context, several studies have already shown the importance of CHD7 for proper function of the neural stem cells (NSCs). Interestingly, we found that CHD7 mRNA levels are upregulated in gliomas, when compared to normal brain tissue, therefore, we hypothesized that CHD7 might have a role in the pathogenesis of these tumors. To investigate the possible oncogenic role of CHD7 in glioblastoma (GBM), we adopted gain- and loss-of-function approaches in adherent GBM cell lines. Using CRISPR_Cas9 genome editing, we found that CHD7 deletion suppresses anchorage-independent growth and reduces spheroid invasion in human LN-229 cells. Moreover, deletion of CHD7 delayed tumor growth and improved overall survival in an orthotopic xenograft glioma mouse model. Conversely, ectopic overexpression of CHD7 in LN-428 and A172 cells was found to increase cell motility and invasiveness in vitro and LN-428 tumor growth in vivo. RNAseq analysis showed that alterations of CHD7 expression levels promote changes in several molecular pathways and modulate critical genes associated with cell adhesion and locomotion. However, the mechanisms underlying the effects of CHD7 overexpression in glioma tissue are still not understood. Here, we also generated recombinant plasmid with functional CHD7 promoter activity reported by luciferase assay. This powerful tool should enable future studies to determine the direct targeting relationship between different signal transduction pathways and CHD7 geneexpression. In summary, our findings indicate that GBM cells expressing a high level of CHD7 may exist and contribute to tumor infiltration and recurrence. Further studies should warrant important clinical-translational implications of our findings for GBM treatment

As proteínas remodeladoras de cromatina exercem importante papel, promovendo modificações dinâmicas na arquitetura da cromatina e dando acesso à maquinaria transcricional ao DNA genômico condensado. Devido à esta função central na regulação da transcrição gênica, a desregulação dessas máquinas moleculares pode levar a perturbações graves na função normal das células. Assim, por exemplo, mutações do tipo perda de função no gene CHD7, um membro da família "chromodomain helicase DNA-binding" (CHD), são a principal causa da síndrome de CHARGE em humanos. A doença é caracterizada por uma variedade de anomalias congênitas, incluindo malformações das estruturas craniofaciais, sistema nervoso periférico, orelhas, olhos e coração. Neste contexto, vários estudos já mostraram a importância da proteína CHD7 para o funcionamento normal de células-tronco neurais (NSCs). Curiosamente, descobrimos que os níveis de mRNA de CHD7 estão mais fortemente expressos em gliomas, quando comparados ao tecido cerebral normal, portanto, nós hipotetizamos que CHD7 poderia ter um papel na patogênese desses tumores. Para investigar o possível papel oncogênico de CHD7 em glioblastoma (GBM), utilizamos enfoques de ganho e perda de função em linhagens celulares aderentes de GBM. Utilizando a técnica de CRISPR_Cas9 para edição do genoma, demonstramos que a deleção do gene CHD7 suprime o crescimento independente de ancoragem e reduz a invasão de esferóides em células LN-229 humanas de GBM. Além disso, a deleção de CHD7 reduziu o crescimento do tumor e melhorou a sobrevida em modelo de injeção ortotópica xenográfica em camundongo. Por outro lado, verificou-se que a super-expressão ectópica de CHD7 nas células LN-428 e A172 aumenta não só a motilidade celular e a capacidade de invasão in vitro, mas, também, o crescimento do tumor de LN-428 in vivo. A análise de RNA-seq mostrou que o nocauteamento da sequência codificadora de CHD7 e sua super-expressão promovem alterações em diversas vias moleculares, modulando genes críticosassociados à adesão e locomoção celular. No entanto, os mecanismos subjacentes aos efeitos da super-expressão de CHD7 em tecidos de glioma ainda não são compreendidos. Neste trabalho, geramos um plasmídeo recombinante contendo um fragmento da região promotora de CHD7, o qual se mostrou funcional em ensaios de luciferase. Esta ferramenta permitirá que estudos futuros possam identificar a relação direta entre as diferentes vias de transdução de sinal e a expressão do gene CHD7. Em resumo, nossos achados indicam que células de GBM expressando um alto nível de CHD7 podem existir e contribuir para a infiltração e recorrência do tumor. Estudos posteriores deverão avaliar as possíveis implicações dos resultados apresentados neste trabalho para a translação clínica no tratamento de pacientes com GBM

MicroRNA-221 promotes cell proliferation, migration, and differentiation by regulation of ZFPM2 in osteoblasts

Bone fracture is a common medical condition, which may occur due to traumatic injury or disease-related conditions. Evidence suggests that microRNAs (miRNAs) can regulate osteoblast differentiation and function. In this study, we explored the effects and mechanism of miR-221 on the growth and migration of osteoblasts using MC3T3-E1 cells. The expression levels of miR-221 in the different groups were measured by qRT-PCR. Then, miR-221 mimic and inhibitor were transfected into MC3T3-E1 cells, and cell viability and migration were measured using the CCK-8 assay and the Transwell migration assay. Additionally, the expression levels of differentiation-related factors (Runx2 and Ocn) and ZFPM2 were measured by qRT-PCR. Western blot was used to measure the expression of cell cycle-related proteins, epithelial-mesenchymal transition (EMT)-related proteins, ZFPM2, and Wnt/Notch, and Smad signaling pathway proteins. miR-221 was significantly up-regulated in the patients with lumbar compression fracture (LCM) and trochanteric fracture (TF). miR-221 promoted ALP, Runx2, and OPN expressions in MC3T3-E1 cells. miR-221 overexpression significantly increased cell proliferation, migration, differentiation, and matrix mineralization, whereas suppression of miR-221 reversed these effects. Additionally, the results displayed that ZFPM2 was a direct target gene of miR-221, and overexpression of ZFPM2 reversed the promoting effects of miR-221 overexpression on osteoblasts. Mechanistic study revealed that overexpression of miR-221 inactivated the Wnt/Notch and Smad signaling pathways by regulating ZFPM2 expression. We drew the conclusions that miR-221 overexpression promoted osteoblast proliferation, migration, and differentiation by regulation of ZFPM2 expression and deactivating the Wnt/Notch and Smad signaling pathways.

Intestinal cell migration damage induced by enteropathogenic Escherichia coli strains

Epithelial cell migration is an essential response to enteric pathogens such as enteropathogenic Escherichia coli (EPEC). This study aimed to investigate the effects of EPEC infection on intestinal epithelial cell migration in vitro, as well as the involvement of type III secretion system (T3SS) and Rho GTPases. Crypt intestinal epithelial cells (IEC-6) were infected with EPEC strains (E2348/69, ΔescF, and the LDI001 strain isolated from a malnourished Brazilian child) and commensal E. coli HS. Wound migration and cell death assays were performed at different time-points. Transcription and expression of Rho GTPases were evaluated using real-time PCR and western blotting. Overall, EPEC E2348/69 reduced migration and increased apoptosis and necrosis levels compared to EPEC LDI001 and E. coli HS strains. Moreover, EPEC LDI001 impaired cell migration at a higher level than E. coli HS and increased necrosis after 24 hours compared to the control group. The different profiles of virulence genes between the two wild-type EPEC strains, characterized by the absence of espL and nleE genes in the LDI001, might explain the phenotypic results, playing significant roles on cell migration impairment and cell death-related events. Moreover, the type III secretion system is determinant for the inhibition of intestinal epithelial cell migration by EPEC 2348/69, as its deletion prevented the effect. Active Rac1 concentrations were increased in E2348/69 and LDI001-infected cells, while the T3SS-deficient strain did not demonstrate this activation. This study contributes with valuable insight to characterize the mechanisms involved in the impairment of intestinal cell migration induced by EPEC.

Effects of platelet-rich plasma on human gingival fibroblast proliferation and migration in vitro

Abstract Objective This study evaluated the influence of platelet-rich plasma (PRP) on the behaviour of human gingival fibroblasts (hGFs), including fibroblast proliferation, migration and colony formation. Methods PRP was obtained from the human peripheral blood of a healthy volunteer and then was diluted into platelet concentrations of 1%, 2% and 5%. The proliferation of hGFs was determined by two methods: (1) Cell-number counting with a haemocytometer method at days 1, 3, 5 and 7; (2) Colony-forming unit-fibroblast (CFU-F) assay at 2 weeks. The migration of hGFs was evaluated with scratch assay, then recorded digital images were analysed by Image-Analysis J 1.51j8 software to compare the remaining artificial wound areas between PRP groups at 0, 24 and 48 hours. Results All hGFs that were cultivated in media with 1%, 2% and 5% PRP showed their ability to proliferate and migrate. Cell numbers incubated with 1% PRP increased significantly during the first three days and peaked at day 5, tending to be similar to their proliferation in complete medium. With concentrations of 2% and 5% PRP, hGFs outgrew and peaked at day 3, which was faster than with those in medium with 1% PRP. Especially, hGFs in the group 5% PRP proliferated with higher cell numbers than those in the other remaining groups at day 3. The hGF colony number that was formed in the group 5% PRP was significantly higher than those in the groups 1% and 2% PRP. Scratch assay showed hGFs in the groups 2% and 5% PRP almost filled the artificial wound and migrated more effectively than in the group 1% PRP at 24 hours, which was significant. Conclusion In this study, perhaps the medium with 5% PRP is the dominant option, promoting the abilities of hGFs to heal wounds, because of its fast and effective impact on cell proliferation, colony formation and migration.

miR-379 Inhibits Cell Proliferation, Invasion, and Migration of Vascular Smooth Muscle Cells by Targeting Insulin-Like Factor-1

PURPOSE: MicroRNAs are small non-coding RNAs that play important roles in vascular smooth muscle cell (VSMC) function. This study investigated the role of miR-379 on proliferation, invasion, and migration of VSMCs and explored underlying mechanisms thereof. MATERIALS AND METHODS: MicroRNA, mRNA, and protein levels were determined by quantitative real-time PCR and western blot. The proliferative, invasive, and migratory abilities of VSMCs were measured by CCK-8, invasion, and wound healing assay, respectively. Luciferase reporter assay was used to confirm the target of miR-379. RESULTS: Platelet-derived growth factor-bb was found to promote cell proliferation and suppress miR-379 expression in VSMCs. Functional assays demonstrated that miR-379 inhibited cell proliferation, cell invasion, and migration. Flow cytometry results further showed that miR-379 induced apoptosis in VSMCs. TargetScan analysis and luciferase report assay confirmed that insulin-like growth factor-1 (IGF-1) 3'UTR is a direct target of miR-379, and mRNA and protein levels of miR-379 and IGF-1 were inversely correlated. Rescue experiments showed that enforced expression of IGF-1 sufficiently overcomes the inhibitory effect of miR-379 on cell proliferation, invasion, and migration in VSMCs. CONCLUSION: Our results suggest that miR-379 plays an important role in regulating VSMCs proliferation, invasion, and migration by targeting IGF-1.

Reprimo as a modulator of cell migration and invasion in the MDA-MB-231 breast cancer cell line

BACKGROUND: Reprimo (RPRM), a highly glycosylated protein, is a new downstream effector of p53-induced cell cycle arrest at the G2/M checkpoint, and a putative tumor suppressor gene frequently silenced via methylation of its promoter region in several malignances. The aim of this study was to characterize the epigenetic inactivation and its biological function in BC cell lines. METHODS: The correlation between RPRM methylation and loss of mRNA expression was assessed in six breast cancer cell lines by methylation specific PCR (MSP), 5'-Aza-2'-deoxycytidine treatment and RT-PCR assays. MDA-MB-231 cells were chosen to investigate the phenotypic effect of RPRM in cell proliferation, cell cycle, cell death, cell migration and invasion. RESULTS: In the cancer methylome system (CMS) (web-based system for visualizing and analyzing genome-wide methylation data of human cancers), the CpG island region of RPRM (1.1 kb) was hypermethylated in breast cancer compared to normal breast tissue; more interesting still was that ERa(+) tumors showed higher methylation intensity than ERa(-). Downregulation of RPRM mRNA by methylation was confirmed in MDA-MB-231 and BT-20 cell lines. In addition, overexpression of RPRM in MDA-MB-231 cells resulted in decreased rates of cell migration, wound healing and invasion in vitro. However, RPRM overexpression did not alter cell viability, phosphatidylserine (PS) translocation or G2/M cell cycle transition. CONCLUSION: Taken together, these data suggest that RPRM is involved in decreased cell migration and invasion in vitro, acting as a potential tumor suppressor gene in the MDA-MB-231 cell line.

Galectin-8 promotes migration and proliferation and prevents apoptosis in U87 glioblastoma cells

BACKGROUND: Glioblastoma is one of the most aggressive cancers of the brain. Malignant traits of glioblastoma cells include elevated migration, proliferation and survival capabilities. Galectins are unconventionally secreted glycan-binding proteins that modulate processes of cell adhesion, migration, proliferation and apoptosis by interacting with beta-galactosides of cell surface glycoproteins and the extracellular matrix. Galectin-8 is one of the galectins highly expressed in glioblastoma cells. It has a unique selectivity for terminally sialylated glycans recently found enhanced in these highly malignant cells. A previous study in glioblastoma cell lines reported that Gal-8 coating a plastic surface stimulates two-dimensional motility. Because in other cells Gal-8 arrests proliferation and induces apoptosis, here we extend its study by analyzing all of these processes in a U87 glioblastoma cell mode.l METHODS: We used immunoblot and RT-PCR for Gal-8 expression analysis, recombinant Gal-8 produced in a bacteria system for Gal-8 treatment of the cells, and shRNA in lentivirus transduction for Gal-8 silencing. Cell migration as assessed in transwell filters. Cell proliferation, cell cycle and apoptosis were analyzed by FACS. RESULTS: Gal-8 as a soluble stimulus triggered chemotactic migration of U87 cells across the polycarbonate filter of transwell chambers, almost as intensively as fetal bovine serum. Unexpectedly, Gal-8 also enhanced U87 cell growth. Co-incubation of Gal-8 with lactose, which blocks galectin-glycan interactions, abrogated both effects. Immunoblot showed Gal-8 in conditioned media reflecting its secretion. U87 cells transduced with silencing shRNA in a lentiviral vector expressed and secreted 30-40 % of their normal Gal-8 levels. These cells maintained their migratory capabilities, but decreased their proliferation rate and underwent higher levels of apoptosis, as revealed by flow cytometry analysis of cell cycle, CFSE and activated caspase-3 staining. Proliferation seemed to be more sensitive than migration to Gal-8 expression levels. CONCLUSIONS: Gal-8, either secreted or exogenously enriched in the media, and acting through extracellular glycan interactions, constitutes a strong stimulus of directional migration in glioblastoma U87 cells and for the first time emerges as a factor that promotes proliferation and prevents apoptosis in cancerous cells. These properties could potentially contribute to the exaggerated malignancy of glioblastoma cells.

Autism in Brazil: a systematic review of family challenges and coping strategies / Autismo no Brasil, desafios familiares e estratégias de superação: revisão sistemática

OBJECTIVE: To describe the challenges faced by families caring for children with autism spectrum disorder (ASD) in Brazil and the coping strategies employed. SOURCES: Systematic review of articles published until September of 2013, without language restrictions, using quality appraisal (AMSTAR and CASP/Oxford instruments). SUMMARY OF THE FINDINGS: The literature shows parental emotional overload as one of the main challenges faced by families, especially mothers. The main stressors were diagnostic postponement, difficulty dealing with the diagnosis and associated symptoms, and poor access to health services and social support. The predominant coping strategies found included information exchange between affected families and integrated healthcare network for patient and family support. CONCLUSION: ASD exerts strong influence on family dynamics, resulting in caregiver overload, especially in mothers. The Brazilian Unified Health System needs to provide comprehensive, continuous, and coordinated care to strengthen the patient-family dyad and promote the full development and societal inclusion of children with ASD. .

OBJETIVO: Descrever os desafios encontrados pelas famílias na convivência com crianças portadoras de transtorno do espectro autista (TEA) no Brasil e as estratégias de superação empregadas. FONTE DOS DADOS: Revisão sistemática da literatura com inclusão de artigos publicados até setembro de 2013, sem restrições de idioma. Os artigos incluídos foram submetidos à avaliação de qualidade metodológica por meio do Amstar e Casp/Oxford. SÍNTESE DOS DADOS: Incluem-se estudos provenientes de São Paulo e Rio Grande do Sul com alta e moderada qualidade metodológica. A literatura mostra sobrecarga emocional dos pais como um dos principais desafios encontrados pelas famílias, inclusive com grande tensão sobre as mães. Dentre os fatores relacionados ao estresse estão: postergação diagnóstica, dificuldade de lidar com o diagnóstico e com os sintomas associados, acesso precário ao serviço de saúde e apoio social. Dentre as estratégias de superação destacaram-se: troca de informações entre as famílias afetadas e assistência integralizada da rede de saúde no atendimento do paciente e suporte à família. CONCLUSÃO: Observou-se que o TEA exerce forte influência na dinâmica familiar com sobrecarga dos cuidadores, geralmente da mãe. O Sistema Único de Saúde necessita prover cuidado integral, longitudinal e coordenado com vistas ao fortalecimento do binômio paciente-família e o pleno desenvolvimento e a plena inserção dessas crianças na sociedade. .

El impacto de los investigadores fieles a la industria farmacéutica en la ética y la calidad de los ensayos clínicos realizados en Latinoamérica / The impact of researchers loyal to Big Pharma on the ethics and quality of clinical trials in Latin America

Este artículo explica las dificultades que tienen las farmacéuticas innovadoras para retribuir a sus accionistas con dividendos atractivos. El problema es el resultado de la caducidad de las patentes de los medicamentos estrella (blockbusters) y las dificultades que tienen en desarrollar nuevos medicamentos estrella. Una solución que las empresas han encontrado es acelerar la ejecución de los ensayos clínicos para obtener, en el menor tiempo posible, el permiso de comercialización y así incrementar el tiempo monopólico de ventas de los nuevos medicamentos. En este contexto, los autores describen la forma en que las farmacéuticas innovadoras acortan el tiempo de ejecución de los ensayos en América Latina y las consecuencias en la calidad de los datos que se obtienen, en la protección de los derechos humanos de los sujetos de experimentación, y en el cumplimiento de los principios éticos aprobados en las declaraciones universales.

This article explains the difficulties innovative pharmaceutical firms have in repaying shareholders with attractive dividends. The problem is the result of the expiration of the patents of blockbuster drugs and the difficulties that the firms have in bringing new blockbuster drugs to the market. One of the solutions companies have found has been to accelerate the implementation of clinical trials in order to expedite the commercialization of new drugs. Doing so increases the period in which they can sell drugs at monopoly prices. We therefore discuss how innovative pharmaceutical firms shorten the implementation time of clinical trials in Latin America and the consequences such actions have on the quality of the collected data, the protection of human rights of the subjects of experimentation, and compliance with the ethical principles approved in international declarations.

Full-genome sequences of hepatitis B virus subgenotype D3 isolates from the Brazilian Amazon Region

The Brazilian Amazon Region is a highly endemic area for hepatitis B virus (HBV). However, little is known regarding the genetic variability of the strains circulating in this geographical region. Here, we describe the first full-length genomes of HBV isolated in the Brazilian Amazon Region; these genomes are also the first complete HBV subgenotype D3 genomes reported for Brazil. The genomes of the five Brazilian isolates were all 3,182 base pairs in length and the isolates were classified as belonging to subgenotype D3, subtypes ayw2 (n = 3) and ayw3 (n = 2). Phylogenetic analysis suggested that the Brazilian sequences are not likely to be closely related to European D3 sequences. Such results will contribute to further epidemiological and evolutionary studies of HBV.

Inhibition of Rho-associated kinases disturbs the collective cell migration of stratified TE-10 cells

BACKGROUND: The collective cell migration of stratified epithelial cells is considered to be an important phenomenon in wound healing, development, and cancer invasion; however, little is known about the mechanisms involved. Furthermore, whereas Rho family proteins, including RhoA, play important roles in cell migration, the exact role of Rho-associated coiled coil-containing protein kinases (ROCKs) in cell migration is controversial and might be cell-type dependent. Here, we report the development of a novel modified scratch assay that was used to observe the collective cell migration of stratified TE-10 cells derived from a human esophageal cancer specimen. RESULTS: Desmosomes were found between the TE-10 cells and microvilli of the surface of the cell sheet. The leading edge of cells in the cell sheet formed a simple layer and moved forward regularly; these rows were followed by the stratified epithelium. ROCK inhibitors and ROCK small interfering RNAs (siRNAs) disturbed not only the collective migration of the leading edge of this cell sheet, but also the stratified layer in the rear. In contrast, RhoA siRNA treatment resulted in more rapid migration of the leading rows and disturbed movement of the stratified portion. CONCLUSIONS: The data presented in this study suggest that ROCKs play an important role in mediating the collective migration of TE-10 cell sheets. In addition, differences between the effects of siRNAs targeting either RhoA or ROCKs suggested that distinct mechanisms regulate the collective cell migration in the simple epithelium of the wound edge versus the stratified layer of the epithelium.

Maintenance of the corneal epithelium is carried out by germinative cells of its basal stratum and not by presumed stem cells of the limbus

The purpose of this investigation was to analyze the proliferative behavior of rabbit corneal epithelium and establish if any particular region was preferentially involved in epithelial maintenance. [3H]-thymidine was injected intravitreally into both normal eyes and eyes with partially scraped corneal epithelium. Semithin sections of the anterior segment were evaluated by quantitative autoradiography. Segments with active replication (on) and those with no cell division (off) were intermingled in all regions of the tissue, suggesting that the renewal of the epithelial surface of the cornea followed an on/off alternating pattern. In the limbus, heavy labeling of the outermost layers was observed, coupled with a few or no labeled nuclei in the basal stratum. This suggests that this region is a site of rapid cell differentiation and does not contain many slow-cycling cells. The conspicuous and protracted labeling of the basal layer of the corneal epithelium suggests that its cells undergo repeated cycles of replication before being sent to the suprabasal strata. This replication model is prone to generate label-retaining cells. Thus, if these are adult stem cells, one must conclude that they reside in the corneal basal layer and not the limbal basal layer. One may also infer that the basal cells of the cornea and not of the limbus are the ones with the main burden of renewing the corneal epithelium. No particular role in this process could be assigned to the cells of the basal layer of the limbal epithelium.

Diabetic retinopathy: could the alpha-1 antitrypsin be a therapeutic option?

Diabetic retinopathy is one of the most important causes of blindness. The underlying mechanisms of this disease include inflammatory changes and remodeling processes of the extracellular-matrix (ECM) leading to pericyte and vascular endothelial cell damage that affects the retinal circulation. In turn, this causes hypoxia leading to release of vascular endothelial growth factor (VEGF) to induce the angiogenesis process. Alpha-1 antitrypsin (AAT) is the most important circulating inhibitor of serine proteases (SERPIN). Its targets include elastase, plasmin, thrombin, trypsin, chymotrypsin, proteinase 3 (PR-3) and plasminogen activator (PAI). AAT modulates the effect of protease-activated receptors (PARs) during inflammatory responses. Plasma levels of AAT can increase 4-fold during acute inflammation then is so-called acute phase protein (APPs). Individuals with low serum levels of AAT could develop disease in lung, liver and pancreas. AAT is involved in extracellular matrix remodeling and inflammation, particularly migration and chemotaxis of neutrophils. It can also suppress nitric oxide (NO) by nitric oxide sintase (NOS) inhibition. AAT binds their targets in an irreversible way resulting in product degradation. The aim of this review is to focus on the points of contact between multiple factors involved in diabetic retinopathy and AAT resembling pleiotropic effects that might be beneficial.

Fibronectin modulates thymocyte-thymic epithelial cell interactions following Trypanosoma cruzi infection

Developing thymocytes interact with thymic epithelial cells (TECs) through cell-cell interactions, TEC-derived secretory moieties and extracellular matrix (ECM)-mediated interactions. These physiological interactions are crucial for normal thymocyte differentiation, but can be disrupted in pathological situations. Indeed, there is severe thymic atrophy in animals acutely infected with Trypanosoma cruzi due to CD4+CD8+ thymocyte depletion secondary to caspase-mediated apoptosis, together with changes in ECM deposition and thymocyte migration. We studied an in vitro model of TEC infection by T. cruzi and found that infected TEC cultures show a reduced number of cells, which was likely associated with decreased proliferative capacity, but not with increased cell death, as demonstrated by bromodeoxyuridine and annexin-V labelling. The infected TEC cultures exhibited increased expression of fibronectin (FN), laminin (LM) and type IV collagen. Importantly, treatment with FN increased the relative number of infected cells, whereas treatment with anti-FN or anti-LM antibodies resulted in lower infection rates. Consistent with these data, we observed increased thymocyte adhesion to infected TEC cultures. Overall, these results suggest that ECM molecules, particularly FN, facilitate infection of the thymic epithelium and that the consequent enhancement of ECM expression might be associated with changes in TEC-thymocyte interactions.