Retracted: MicroRNA‐21 promotes glioma cell proliferation and inhibits senescence and apoptosis by targeting SPRY1 via the PTEN/PI3K/AKT signaling pathway

Abstract

Our study aims to investigate the effect of microRNA-21 (miR-21) on the proliferation, senescence, and apoptosis of glioma cells by targeting SPRY1 via the PTEN/PI3K/AKT signaling pathway. Glioma tissues and brain tissues were collected for this study after surgical decompression for traumatic brain injury. RT-qPCR was employed to measure mRNA levels of miR-21, SPRY1, PTEN, PI3K, and AKT, and Western blotting was conducted to determine protein levels of SPRY1, PTEN, PI3K, AKT, p-AKT, Caspase-3, Caspase-9, P53, GSK3, and p-GSK3. Human glioma U87 cells were assigned into the blank, negative control (NC), miR-21 mimics, miR-21 inhibitors, siRNA-SPRY1, and miR-21 inhibitors + siRNA-SPRY1 groups, with human HEB cells serving as the normal group. Cell proliferation, cell cycle, and apoptosis were determined by MTT and flow cytometry, respectively. Compared with control group, an increased expression of miR-21, PI3K, AKT, p-AKT, P53, and p-GSK3, and a decreased expression of SPRY1, PTEN, Caspase-3, and Caspase-9 were observed in the glioma group, and no significant differences were found in the expression of GSK3. SPRY1 was verified to be the target gene of miR-21. Compared with the blank and NC groups, levels of PI3K, AKT, p-AKT, P53, and p-GSK3 increased while levels of SPRY1, PTEN, Caspase-3, and Caspase-9 decreased in the miR-21 mimics and siRNA-SPRY1 groups; the miR-21 inhibitors group reversed the tendency; furthermore, the miR-21 inhibitors group showed decreased cell proliferation but promoted apoptosis, which were opposite to the results of the miR-21 mimics and siRNA-SPRY1 groups. MicroRNA-21 might promote cell proliferation and inhibit cell senescence and apoptosis of human glioma cells by targeting SPRY1 via the PTEN/PI3K/AKT signaling pathway.