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AIM: To study the effects and mechanism of down-regulating lncRNA LINC00176 on cisplatin resistance and autophagy in lung cancer A549/DDP cells. METHODS: The qRT-PCR method was used to determine the expression changes of LINC00176 in normal bronchial epithelial 16HBE cells and lung cancer A549, A549/DDP, NCI-H1299 and SK-MES-1 cells. A549/DDP cells were divided into Control group, si-NC group, and si-LINC00176 group, si-LINC00176+ Anti-miR-NC group, and si-LINC00176+ Anti-miR-138-5p group. MTT experiment detected the half inhibitory concentration (IC
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AIM: To study the effect of miR-138-5p on the function of β cell in gestational diabetes mellitus (GDM) and its related mechanism. METHODS: The expression of miR-138-5p in peripheral blood of 15 GDM pregnant women and 15 normal pregnant women were compared by RT-qPCR. miR-138-5p mimic and inhibitor were transfected into INS-1 cells, respectively, and their expression level was over expressed or inhibited. RT-qPCR was used to verify the transfection efficiency.MTT proliferation experiment, Annexin V-FITC apoptosis experiment and insulin release experiment were used to detect the effects of miR-138-5p on INS-1 cell proliferation, apoptosis and insulin release ability. The target gene of miR-138-5p was screened by TargetScan, a miRNA target gene prediction software. The functional rescue experiment confirmed whether miR-138-5p could exert its influence on INS-1 cell proliferation, apoptosis and insulin release ability by targeting its target gene. Western blot was used to detect the molecular signaling pathway of miR-138-5p in INS-1 cells.RESULTS: The expression of miR-138-5p in peripheral blood of GDM pregnant women was significantly lower than that of normal pregnant women. RT-qPCR showed that miR-138-5p mimic and inhibitor could significantly promote or inhibit the expression of miR-138-5p in INS-1 cells. The results of MTT proliferation experiment, Annexin V-FITC apoptosis experiment and insulin release experiment indicated that over expression of miR-138-5p could significantly promote the proliferation of INS-1 cells, inhibit the apoptosis of cells and promote the insulin release ability of cells. However, down-regulating the expression of miR-138-5p could significantly inhibit the proliferation of INS-1 cells, promote apoptosis and inhibit insulin release. HIF-1α was selected as the target gene of miR-138-5p by TargetScan. The double luciferase gene report and Western blot showed that miR-138-5p could inhibit the expression of HIF-1α in INS-1 cells. The functional rescue experiment confirmed that miR-138-5p could affect the proliferation, apoptosis and insulin release of INS-1 cells by regulating the expression of HIF-1α. Western blot showed that miR-138-5p may play a role in INS-1 cells by affecting PI3K, Akt and p-PI3K, p-Akt protein after phosphorylation in PI3K/Akt signaling pathway. CONCLUSION: miR-138-5p may reguLate HIF-1α expression in a targeted manner, thereby affecting the PI3K/AKT signaling pathway, promoting the proliferation and inhibition of the parent cells' apoptosis, and promoting their insulin-releasing ability to protect the function of β cell in GDM.
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BACKGROUND: Cisplatin resistance (DDP-resistance) remains one of the major causes of poor prognosis in females with ovarian cancer. Long non-coding RNAs (lncRNAs) have been shown to participate in the regulation of cellular processes, including chemoresistance. The aim of this study was to explore the role of HOX transcript antisense RNA (HOTAIR) in DDP-resistant ovarian cancer cells. METHODS: DDP-resistant ovarian cancer cell lines (SKOV3/DDP and A2780/DDP) were established. Real-time PCR, western blot, dual-luciferase reporter assay, and flow cytometry were then used to evaluate the effect of HOTAIR/miR-138-5p axis on chemoresistance of DDP-resistant ovarian cancer cells to DDP. RESULTS: We found that HOTAIR was upregulated in DDP-resistant cells, while miR-138-5p was downregulated. Knockdown of HOTAIR increased the expression of miR-138-5p in DDP-resistant cells and miR-138-5p is directly bound to HOTAIR. Upregulation of miR-138-5p induced by HOTAIR siRNA or by its mimics enhanced the chemosensitivity of DDP-resistant cells and decreased the expression of EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit) and SIRT1 (sirtuin 1). Furthermore, the HOTAIR silencing-induced chemosensitivity of DDP-resistant cells was weakened by miR-138-5p inhibitor. CONCLUSIONS: These data demonstrate that HOTAIR acts as a sponge of miR-138-5p to prevent its binding to EZH2 and SIRT1, thereby promoting DDP-resistance of ovarian cancer cells. Our work will shed light on the development of therapeutic strategies for ovarian cancer treatment.