ABSTRACT
Objective:To explore the inhibitory effect of long non-coding RNA (lncRNA) KCNQ1 overlapping transcript 1 (KCNQ1OT1) by targeting microRNA-199a-5p (miR-199a-5p) on the apoptosis of human lens epithelial cells (LECs).Methods:The anterior lens capsule tissue of 23 age-related cataract patients who underwent cataract surgery in Xinxiang First People's Hospital from December 2018 to August 2019 was collected.At the same time, anterior lens capsules from 20 healthy donor were collected.The expressions of KCNQ1OT1 and miR-199a-5p in the tissues were detected by real-time fluorescence PCR.Human LECs SRA01/04 cultured in vitro were divided into blank control group, model control group, small interfering RNA-negative control (siR-NC) group, siR-KCNQ1OT1 group, miR-NC group, miR-199a-5p group, siR-KCNQ1OT1+ anti-miR-NC group and siR-KCNQ1OT1+ anti-miR-199a-5p group.No intervention was administered to blank control group.Cells in model control group were cultured with 100 μmol/L H 2O 2 for 24 hours to establish oxidative stress injured model, and cells in the other six groups were transfected with corresponding transfection reagents for 6 hours by liposome method according to grouping, and then treated with 100 μmol/L H 2O 2 for 24 hours.The expressions of KCNQ1OT1 and miR-199a-5p in lens anterior capsule tissue and LECs cells were determined by real-time fluorescent quantitative PCR.Cell viability was detected with thiazolyl blue (MTT). Cell apoptosis was analyzed by flow cytometry.The expressions of B-cell lymphoma/leukemia-2 (bcl-2) and bcl-2 related X protein (Bax) proteins were assayed by Western blot.The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were measured by enzyme-linked immunosorbent assay (ELISA). The targeting relationship between KCNQ1OT1 and miR-199a-5p was verified by dual luciferase reporter experiment.The study protocol was approved by an Ethics Committee of Xinxiang First People's Hospital (No.2019-001). Written informed consent was obtained from relatives of patient. Results:The relative expression of KCNQ1OT1 in the anterior capsule of patients with age-related cataract was 2.41±0.42, which was significantly higher than 0.97±0.19 of normal people, and the relative expression of miR-199a-5p in the capsule of patients with age-related cataract was 0.36±0.12, which was lower than 1.04±0.15 of normal people, and the differences were statistically significant ( t=14.112, 16.507; both at P<0.001). Compared with blank control group, the relative expressions of KCNQ1OT1 and bax protein, cell apoptosis rate and MDA content were significantly increased, and the relative expressions of miR-199a-5p and bcl-2 protein, cell viability and SOD activity were significantly reduced in model control group, showing statistically significant differences (all at P<0.001). Compared with siR-NC group, the relative expressions of KCNQ1OT1 and bax protein, cell apoptosis rate and MDA content in cells of siR-KCNQ1OT1 group were decreased, while the relative expression of bcl-2 protein, cell survival rate and SOD activity were increased, and the differences were statistically significant (all at P<0.05). Compared with miR-NC group, the KCNQ1OT1-wild type (WT) luciferase activity in miR-199a-5p group was significantly decreased, with a statistically significant difference ( t=21.131, P<0.001). The relative expression levels of miR-199a-5p and bcl-2 proteins, cell survival rate and SOD activity were significantly increased, and the relative expression of bax protein, cell apoptosis rate and MDA content were significantly decreased in miR-199a-5p group than those in miR-NC group, and the differences were statistically significant (all at P<0.05). The relative expression levels of miR-199a-5p and bcl-2 proteins, cell survival rate and SOD activity were significantly lower, and the cell apoptosis rate, relative expression of bax protein and MDA content were significantly higher in siR-KCNQ1OT1+ anti-miR-199a-5p group than those in siR-KCNQ1OT1+ anti-miR-NC group, and the differences were statistically significant (all at P<0.05). Conclusions:The inhibition of KCNQ1OT1 can promote the cell viability of human LECs, inhibit H 2O 2-induced cell apoptosis and oxidative stress, and the mechanism may be related to the up-regulation of miR-199a-5p.
ABSTRACT
Dendrobium nobile Lindl. alkaloids (DNLA) promote the apoptosis of breast cancer and colon cancer cells, but whether they affect the malignant biological behavior of cervical cancer cells is unknown. Herein we explored the effects and possible mechanisms of DNLA on the proliferation, apoptosis, migration and invasion of cervical cancer SiHa cells. SiHa cells were transfected with si-NC, siKCNQ1OT1, miR-NC, miR-487a-3p mimics, pcDNA-NC or pcDNA-KCNQ1OT1. Different doses (15, 30, 60 ng/mL) of DNLA were applied. The CCK-8 method was used to detect cell proliferation; Tran-swell was used to detect cell migration and invasion; flow cytometry was used to detect cell apoptosis; Western blotting was used to detect the expression of MMP2, MMP9 and Cleaved-Caspase-3 genes at the protein level; RT-qPCR was used to detect the expression of KCNQ1OT1 and miR-487a-3p. The dual luciferase reporter gene experiment verified the regulatory relationship between KCNQ1OT1 and miR-487a-3p. The results showed that different doses (15, 30, 60 ng/mL) of DNLA reduced the absorbance value, migration number, invasion number, the protein level of MMP2 and MMP9, reduced the expression of KCNQ1OT1, and increased the apoptosis rate, the abundance of Cleaved-Caspase-3 and the expression of miR-487a-3p (P<0. 05). Low expression of KCNQ1OT1 or high expression of miR-487a-3p reduced the absorbance value, migration number, invasion number, and the protein level of MMP2 and MMP9, but increased the apoptosis rate and the abundance of Cleaved-Caspase-3 (P<0. 05). KCNQ1OT1 negatively regulated the expression of miR-487a-3p. The effects of high expression of KCNQ1OT1 on the proliferation, apoptosis, migration and invasion of SiHa cells were opposite to that of low expression of KCNQ1OT1, and high expression of KCNQ1OT1 reduced the effects of 60 ng/mL DNLA on the proliferation, apoptosis, migration and invasion of SiHa cells. In summary, DNLA may reduce the proliferation, migration and invasion of cervical cancer SiHa cells and promote SiHa cell apoptosis by regulating the KCNQ1OT1/miR-487a-3p axis.
ABSTRACT
Abstract Background: Osteoarthritis (OA) is defined as a degenerative disease. Pivotal roles of long non-coding RNA (lncRNAs) in OA are widely elucidated. Herein, we intend to explore the function and molecular mechanism of lncRNA KCNQ1OT1 in CHON-001 cells. Methods: Relative expression of KCNQ1OT1, miR-126-5p and TRPS1 was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability was examined by MTT assay. The migratory ability of chondrocytes was assessed by transwell assay. Western blot was used to determine relative protein expression of collagen II, MMP13 and TRPS1. Dual-luciferase reporter (DLR) assay was applied to test the target of lncRNA KCNQ1OT1 or miR-126-5p. Results: Relative expression of KCNQ1OT1 and TRPS1 was reduced, whereas miR-126-5p was augmented in cartilage tissues of post-traumatic OA patients compared to those of subjects without post-traumatic OA. Increased KCNQ1OT1 or decreased miR-126-5p enhanced cell viability and migration, and repressed extracellular matrix (ECM) degradation in CHON-001 cells. MiR-126-5p was the downstream target of KCNQ1OT1, and it could directly target TRPS1. There was an inverse correlation between KCNQ1OT1 and miR-126-5p or between miR-126-5p and TRPS1. Meantime, there was a positive correlation between KCNQ1OT1 and TRPS1. The promoting impacts of KCNQ1OT1 on cell viability and migration as well as the suppressive impact of KCNQ1OT1 on ECM degradation were partially abolished by miR-126-5p overexpression or TRPS1 knockdown in CHON-001 cells. Conclusions: Overexpression of KCNQ1OT1 attenuates the development of OA by sponging miR-126-5p to target TRPS1. Our findings may provide a possible therapeutic strategy for human OA in clinic.