Effect of Mir-299-3p on the biological function of lung adenocarcinoma cell H1299 through targeting PTPRD

The paper aimed to investigate the effects of up-regulation and down-regulation of Mir-299-3p on the proliferation, migration, invasion and apoptosis of lung adenocarcinoma cell line H1299, and to preliminarily explore the mechanism of Mir-299-3p regulating the biological behavior of lung adenocarcinoma cells. Mir-299-3p inhibitor and Mir-299-3p mimics were transfected into lung adenocarcinoma cell line H1299, and the transfection efficiency was measured by fluorescence microscopy. The successfully transfected lung adenocarcinoma cells were detected of proliferation, migration, invasion, and apoptosis. Mir-299-3p inhibitor and Mir-299-3p mimics were used to down-regulate and up-regulate Mir-299-3p respectively. Western blot was employed to detect the expressions of STAT3, p-STAT3, caspase3, Bcl-2, Bax and MMP-9 proteins in lung adenocarcinoma cells. Small interfering RNA technology was applied to construct a cell line with low expression of PTPRD. WB was used to measure the transfection efficiency to determine whether the down-regulation of PTPRD can partially or completely reverse the proliferation, migration, invasion, and apoptosis of lung adenocarcinoma cells after the down-regulation of Mir-299-3p. It was also determined whether the down-regulation of PTPRD can partially or completely reverse the effect of Mir-299-3p down-regulation on the expressions of p-STAT3, MMP-9, Cleaved-caspase3, Bcl-2 and Bax proteins in lung adenocarcinoma cells. Down-regulation of Mir-299-3p can inhibit the proliferation and invasion of lung adenocarcinoma cell H1299, promote cell apoptosis, inhibit the expression of p-STAT3 and MMP-9, promote the expressions of apoptosis-inducing proteins such as Bax and Cleaved-caspase3, and also inhibit the expression of apoptosis inhibitor protein Bcl-2. The up-regulation of Mir-299-3p worked in the opposite way.