MicroRNA-142-3p suppresses cell proliferation and migration in bladder cancer via Rac1

Expression of microRNA(miR)-142-3p has been implicated to be associated with several cancers, whereas its function in bladder cancer (BC) remains unknown. The present study aimed to explore the correlation between the expression of miR-142-3p and the proliferation, migration and invasion of bladder cancer cells by activating Rac1. qRT-PCR was used to measure the expression of miR-142- 3p in bladder cancer tissues and cell lines. RNA transfection was used to silence and accelerate the expression of miR-142-3p in bladder cancer cells. CCK-8 and trans-well assays were used to detect the proliferation, migration and invasion of cells before and after RNA transfection. The direct interaction between Rac1 and miR-142-3p was demonstrated by a dual luciferase reporter assay. qRT-PCR and Western blot assays were used to detect the expression changes in Rac1 before and after transfection. The results showed that miR-142-3p in bladder cancer tissues was significantly lower than that in adjacent tissues and lower than that in HT1376 and T-24 cells but higher than that in T5637 and BIU- 87 cells. Additionally, upregulating miR-142-3p expression not only inhibits the proliferation of SV-HUC-1 and BIU-87 cells but also inhibits migration and invasion, and downregulating miR-142-3p expression showed the opposite results. The expression of Rac1 was promoted after stimulating miR- 142-3p expression, but was inhibited after silencing miR-142-3p expression. In conclusion, miR-142-3p affects the proliferation, migration and invasion of bladder cancer cells by regulating Rac1.

[Effect and related mechanisms of RTA-408 on rat vascular smooth muscle cell calcification induced by advanced glycation end products]

Objective: To investigate the effect and related mechanisms of RTA-408 on rat vascular smooth muscle cells (VSMCs) calcification induced by advanced glycation end products(AGE). Methods: VSMCs were isolated from the aorta of Sprague Dawley rats and cultured in vitro. The fifth generation of VSMCs were randomly divided into 4 groups with random number table including control group(cells were incubated with normal medium for 2 days, then incubated with bovine serum albumin for 5 days),AGE group (cells were incubated with normal medium for 2 days, then incubated with 200 mg/L AGE for 5 days), experimental group(cells were incubated with 100 nmol/L RTA-408 for 2 days,then incubated with 200 mg/L AGE for 5 days),and RTA group(cells were incubated with 100 nmol/L RTA-408 for 2 days,then incubated with bovine serum albumin for 5 days). Cytosolic calciumin VSMC was measured using arsenazo Ⅲ assay. Von Kossa staining was utilized to detect the calcium deposition.The contents of malondialdehyde(MDA) and superoxide dismutase(SOD) in VSMCs were tested by appropriate kits.The protein expressions of osteopontin (OPN), alkaline phosphatase (ALP), nuclear factor E2 related factor 2(Nrf2), and NAD(P)H: quinone oxidoreductase 1(NQO1) were examined using Western blot. Results: (1) Cytosolic calciumconcentration was significantly higher in AGE group than in control group((2.43±0.15) mmol/L vs. (1.23±0.09) mmol/L, P<0.01), which was significantly reduced in experimental group((1.62±0.18) mmol/L,P<0.01 vs. AGE group). (2) Calcium deposition in VSMCs was significantly upregulated in AGE group than in control group(3.64±0.50 vs. 1.00±0.12, P<0.01), and was downregulated in experimental group (1.56±0.37, P<0.01 vs. AGE group). (3) The MDA contents were higher((3.79±0.27) nmol/mg prot vs.(1.99±0.15) nmol/mg prot, P<0.01), while the SOD activities were lower((308.45±14.28) U/mg prot vs. (428.58±11.00) U/mg prot, P<0.01) in AGE group than in control group. The MDA contents were lower((2.37±0.19) nmol/mg prot vs. (3.79±0.27) nmol/mg prot, P<0.01),while the SOD activities were higher((391.03±22.92) U/mg prot vs. (308.45±14.28) U/mg prot, P<0.05)in experimental group compared with AGE group. (4) The relative expressions of OPN and ALP were higher in AGE group than in control group(3.06±0.21 vs. 1.00±0.07, and 2.89±0.29 vs. 1.00±0.10,both P<0.01), both (OPN(1.15±0.12) and ALP(1.45±0.15)) were downregulated in experimental group (both P<0.01 vs. AGE group). (5) The relative protein expressions of Nrf2 and NQO1 in experimental group were higher than AGE group(2.37±0.17 vs. 1.17±0.09, and 3.91±0.18 vs. 1.05±0.08, both P<0.01). Conclusion: Activation of nrf2/NQO1 signaling pathway by RTA-408 can reduce the AGE-induced VSMC calcification through attenuating oxidative injury.