RESUMO
@#[Abstract] Objective: To investigate the effects of exosome originated from bone marrow mesenchymal stem cell (BMSCs) on proliferation, migration and invasion of prostate cancer PC-3 cell and its mechanism. Methods: qPCR was used to detect the expression level of miR-21-5p in prostate cancer cell lines. The morphology of exosomes isolated from BMSCs was observed with an electron microscope. Western blotting was used to detect the expressions of exosome surface markers and the epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin and Vimentin). Dual luciferase reporter gene experiment was used to detect the targeted regulation relationship between miR-21-5p and PH domain leucine-rich repeat protein phosphatase 2 (PHLPP2). PC-3 cells were co-cultured with 10 μl BMSCs exosomes suspension (Exo group), transfected with sh-PHLPP2 or antagomiR, then CCK-8 and Transwell experiments were used to detect changesinproliferation,migrationandinvasionofPC-3cell.Results: miR-21-5p was highly expressed in prostate cancer PC-3 cell line. The exosomes in the supernatant of BMSCs culture fluid were successfully isolated, and the typical vesicle-like structures of exosomes were observed under transmission electron microscope. Exosomes expressed specific proteins such as CD9, CD63 and CD81. In the Exo group, the proliferation, invasion, migration, as well as the expressions of N-cadherin, Vimentin and miR-21-5p in PC-3 cells were significantly higher than those in the control group (all P<0.05). PHLPP2 is a target gene of miR-21-5p. Compared with the control group, the expression of PHLPP2 in PC-3 cells of Exo group and sh-PHLPP2 group was significantly reduced (0.66±0.09, 0.42±0.05 vs 1.09±0.08, all P<0.01); cell viability, invasion and migration were significantly improved (all P<0.01); and E-cadherin expression level was significantly reduced while N-cadherin and Vimentin expressions were significantly increased (both P<0.05). Conclusion: miR-21-5p is highly expressed in prostate cancer PC-3 cell line. BMSC exosome miR-21-5p can increase the proliferation, migration and invasion ability of PC-3 cells through targeted down-regulation of PHLPP2.
RESUMO
@# Objective: To explore the effect of histone deacetylase (HDAC) inhibitor valproic acid (VPA) on the epithelial-mesenchymal transition (EMT) of colon cancer. Methods: With four colon carcinoma cell lines (DLD-1, HCT116, SW480 and HT29) as study subjects, the effect of different concentrations of VPA(0.5，5 mmol/L) on cell proliferation was detected by MTT assay. The expression level of EMT-related proteins (E-cadherin and vimentin) was detected by Western blotting; Phenotypic changes of E-cadherin and vimentin were detected by immunofluorescence staining; Cell migration and invasion ability was detected by wound healing and Transwell invasion assay, respectively. Results:After treated with different concentrations of VPAfor 48 h, low concentration of VPAmerely exerted any effect on the cell proliferation rate of four colon cancer cell lines, and thus was chosen as the experiment concentration; The results of Western blotting showed that the expression of E-cadherin was reduced (P<0.05) and vimentin was increased (P<0.05) in colon carcinoma cells by VPAtreatment (0.5 mmol/L); Immunofluorescence staining revealed membranous attenuation or nuclear translocation of E-cadherin and enhanced expression of vimentin after VPA treatment (0.5 mmol/L), and these responses occurred after 6 h and sustained until 24 h; Wound healing and Transwell invasion assay showed increased migration and invasion ability following VPA treatment (0.5 mmol/L). Conclusion: Low concentration VPA could induce the development of EMT in colon cancer cells by nuclear translocation of E-cadherin, and obviously enhance the migration and invasion ability of colon cancer cells; Thus, HDAC inhibitors, as a new type anti-cancer option, shall be carefully considered before their application in colon cancer.