Long non-coding RNA BDNF-AS inhibits the proliferation and migration of renal cancer cells by regulating PI3K-AKT signaling pathway through protein tyrosine phosphatase receptor type G / 肿瘤研究与临床

ABSTRACT

Objective:To investigate the expression of long non-coding RNA (lncRNA) BDNF-AS in kidney cancer tissues, and its effect on the proliferation and migration ability of kidney cancer cells and the molecular mechanism.Methods:Real-time reverse quantitative polymerase chain reaction (rRT-PCR) was used to detect the expression levels of BDNF-AS gene in renal cancer tissues, tumor-adjacent tissues of 67 renal cancer patients and normal renal tubular epithelial cells HK-2 and renal cancer cell lines A498, ACHN, OS-RC-2, Caki-1, 786-O in Huangshi Central Hospital of Edong Medical Group from May 2017 to July 2018. The kidney cancer cell line with the lowest expression of BDNF-AS was taken as the research object. Transient transfection with BDNF-AS overexpression plasmid was treated as the experiment group or a plasmid carrying meaningless sequences was treated as the control group. rRT-PCR was used to detect transfection efficiency. After the transfection with Caki-1 for 24 h, methythiazolyl tetrazolium (MTT) method was used to detect the proliferation of cells in both groups, Transwell migration assay was applied to detect the cell migration ability, rRT-PCR was used to detect the expression level of protein tyrosine phosphatase receptor type G (PTPRG) mRNA and Western blot was used to detect the expression level of PI3K-AKT pathway related-proteins.Results:The relative expression level of BDNF-AS in kidney cancer tissues was lower than that in tumor-adjacent tissues (0.96±0.24 vs. 4.62±0.84, t = 41.76, P < 0.01). The relative expression of BDNF-AS in kidney cancer cell lines was lower than that in normal renal tubular epithelial cells HK-2 (all P < 0.05), and the relative expression in Caki-1 cells was the lowest (0.10±0.01). The relative expression of BDNF-AS in the experimental group was higher than that in the control group ( P < 0.01). From the second day of transfection, the proliferation ability of Caki-1 cells in the experimental group was lower than that in the control group (all P < 0.05). The number of Caki-1 migrated cells in the experimental group was lower than that in the control group after migration for 15 h of Caki-1 cells transfected for 24 h [(51±8) vs. (192±25), t = 5.31, P < 0.01]. After 48 h transfection, the relative expression of PTPRG mRNA in Caki-1 cells ( P < 0.01) and protein expression of the experimental group were higher than those of the control group, the expression levels of PI3K-AKT signaling pathway related-proteins p-PI3K, p-AKT, p-Tpl2 in Caki-1 cells of the experimental group were lower than those of the control group. Conclusions:The expression of BDNF-AS is down-regulated in kidney cancer tissues and cell lines. Overexpression of BDNF-AS can inhibit the proliferation and migration ability of kidney cancer Caki-1 cells. The molecular mechanism may be related to the transduction that BDNF-AS promotes PTPRG gene expression and interferes with PI3K-AKT signaling pathway.