ABSTRACT
Objective: To explore the expression levels of miR-23a-3p and miR-27a-3p in the sera of mice with ulcerative colitis (UC) and their potential action mechanisms. Methods: Twenty C57BL/6 mice were randomly divided into the control group and the model group with 10 mice in each group. The model group mice were induced orally by water with 5% dextran sulfate sodium (DSS) for 7 d. During the induction period, the general condition, fecal morphology and occult blood status of the mice were observed. After 7 d, the whole blood and colon tissues of mice were collected, and the colon lengths and wet weights were measured. The expressions of miR-23a-3p and miR-27a-3p in the sera were detected by qRT-PCR. The expressions of peroxisome proliferator-activated receptor γ, coactivator-1α (PPARGC1A), PH domain leucine-rich repeat protein phosphatase 2 (PHLPP2), B-cell lymphoma-2 (BCL-2), BCL-2 associated X protein (BAX), cytochrome c (CYT-C) and cleaved cysteine-containing aspartate-specific protease (cleaved-caspase-3) were detected by Western blotting. Results: After DSS induction, the model group mice showed mental depression, weight loss, diarrhea, and bloody stool, whose colon lengths were shortened and colon wet weights decreased. The UC model was constructed successfully. In the model group, the expressions of miR-23a-3p and miR-27a-3p in the sera decreased significantly (P<0.05), and the expressions of PPARGC1A, PHLPP2, BAX, CYT-C and cleavedcaspase- 3 in the colon tissues increased significantly (P<0.05), but BCL-2 decreased (P<0.05). Conclusion: The expressions of miR-23a-3p and miR- 27a-3p are low in the sera of UC mice, which may be involved in the occurrence and development of UC by up regulating the expressions of PPARGC1A and PHLPP2 in the colons and triggering mitochondrial pathway to induce apoptosis.
ABSTRACT
@#[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.
ABSTRACT
Objective To investigate the effect and underlying mechanism of single,fractioned and continuous low dose rate radiation on CL187 colorectal cancer cell line.Methods CL187 cells were exposed to 6 MV X-rays at a high dose rate of 4 Gy/min and 125Ⅰ seed at a low dose rate of 2.77 cGy/h with three groups:single dose radiation group (SDR),fractioned dose radiation group (FDR) by 2 Gy/f,and continuous low dose rate radiation group (CLDR).The radiation doses were 0,2,4 and 8 Gy.Total cell number and cell viability were determined by trypan blue.Clone forming assay was used to evaluate the cell proliferation ability.The percentage of apoptosis cells was analyzed by flow cytometry.Western blot was used to detect the protein expression levels of PHLPP2,PTEN and Bax.Results Compared with SDR and FDR groups,the total cell number and survival fraction of CLDR group decreased.The relative biological effect (RBE) for 125Ⅰ seeds compared with 6 MV X-rays was 1.41.The percentage of apoptosis cells of CLDR group was significantly increased (t =-15.08,-11.99,P ＜ 0.05).The expression level of Bax increased in CLDR group,while no obvious changes were observed on PHLPP2 and PTEN among three groups.Conclusions The expression level of PHLPP2 increaseS in SDR,FDR and CLDR group,while it seems that it was not influenced by dose rate.The expression level of Bax increased in three groups,while more colorectal CL187 cells in CLDR group may be killed due to the increase of Bax expression.