Qu Fei, Wang Xiufen
Pharmazie. 2017 Aug 1;72(8):482-486. doi: 10.1691/ph.2017.7501.
Aberrant expression of miR-340 has been found in several kinds of cancers including ovarian cancer. Pro-apoptotic and anti-metastasis roles of miR-340 in ovarian cancer have also been reported; however, the underling molecular mechanisms by which miR-340 suppresses ovarian cancer are still unclear. This study focused on the role and molecular mechanism of miR-340 in ovarian cancer. Human ovarian carcinoma SKOV3 cells were used and transfected with miR-340 mimic, miR-340 inhibitor and their correspondingly negative controls (mimic control and inhibitor control). Thereafter, cell viability, apoptosis, and the expressions of apoptosis-associated factors and BAG3 were respectively assessed by MTT assay, flow cytometry, qRT-PCR and Western blotting. SKOV3 cells were then co-transfected with miR-340 inhibitor and BAG3 targeted siRNA, then cell viability, apoptosis and the expression of apoptosis-associated factors were retested. Besides, the expressions of main factors in PI3K/AKT pathway were detected. Overexpression of miR-340 suppressed BAG3 cells viability (P < 0.05), but improved apoptosis (P < 0.001). BAG3 was negatively regulated by miR-340 (P < 0.05 or P < 0.01). BAG3 silence significantly induced cell apoptosis (P < 0.001), and abolished miR-340 suppression-induced increase in cell viability (P < 0.001). Besides, BAG3 silence abolished miR-340 suppression-induced activation of PI3K and AKT. This study revealed the tumor suppressive role of miR-340 in SKOV3 cells by negative regulation of BAG3. PI3K/AKT pathway might be involved in the regulation of miR-340 and BAG3.
已发现在包括卵巢癌在内的多种癌症中存在miR - 340的异常表达。也有报道称miR - 340在卵巢癌中具有促凋亡和抗转移作用；然而，miR - 340抑制卵巢癌的潜在分子机制仍不清楚。本研究聚焦于miR - 340在卵巢癌中的作用及分子机制。使用人卵巢癌细胞系SKOV3细胞，并分别用miR - 340模拟物、miR - 340抑制剂及其相应的阴性对照（模拟物对照和抑制剂对照）进行转染。此后，通过MTT法、流式细胞术、qRT - PCR和蛋白质印迹分别评估细胞活力、凋亡以及凋亡相关因子和BAG3的表达。然后将SKOV3细胞与miR - 340抑制剂和靶向BAG3的小干扰RNA（siRNA）共转染，随后重新检测细胞活力、凋亡以及凋亡相关因子的表达。此外，检测PI3K/AKT通路中主要因子的表达。miR - 340的过表达抑制了BAG3细胞的活力（P < 0.05），但促进了凋亡（P < 0.001）。BAG3受到miR - 340的负调控（P < 0.05或P < 0.01）。BAG3沉默显著诱导细胞凋亡（P < 0.001），并消除了miR - 340抑制诱导的细胞活力增加（P < 0.001）。此外，BAG3沉默消除了miR - 340抑制诱导的PI3K和AKT的激活。本研究揭示了miR - 340通过对BAG3的负调控在SKOV3细胞中的肿瘤抑制作用。PI3K/AKT通路可能参与了miR - 340和BAG3的调控。
