The mechanism of miR-16-5p protection on LPS-induced A549 cell injury by targeting CXCR3.

OBJECTIVE: To study the effect of miR-16-5p on lung cancer cell injury and apoptosis, and its mechanism. METHODS: LPS induced lung cancer cell A549 injury; qRT-PCR method was applied to detect the expression of miR-16-5p and CXCR3 in A549 cells. Con (without LPS treatment), LPS + miR-NC group (transfected negative control samples), LPS + miR-16-5p group (transfected miR-16-5p mimics); LPS + si-NC group (transfected negative control samples), LPS + si-CXCR3 group (transfected si-CXCR3); LPS + miR-16-5p + pcDNA3.1 group (co-transfected miR-16-5p mimics and pcDNA3.1), LPS + miR-16-5p + pcDNA3.1-CXCR3 group (co-transfected miR-16-5p mimics and pcDNA3.1-CXCR3) were transfected into A549 cells by liposome method. Western blot was used to detect protein expression of CXCR3, IL-6 and TNF-α in A549 cells; apoptosis of A549 cells was detected by flow cytometry. RESULTS: Compared with the control group, the expression of miR-16-5p mRNA was significantly decreased in A549 cells in LPS group, and the mRNA and protein expression of CXCR3 were significantly increased (p < .05). Overexpression of miR-16-5p and knockdown of CXCR3 both can down-regulated protein expression of IL-6 and TNF-α, and up-regulated apoptosis in LPS-induced A549 cell; CXCR3 is a target of miR-16-5p. Overexpression of CXCR3 rescued the protective effect of miR-16-5p on LPS-induced A549 cell injury. CONCLUSION: miR-16-5p can protect LPS-induced A549 cell injury, and its mechanism may be related to the targeted regulation of CXCR3, which could provide a new target for targeted therapy of lung cancer.

Downregulation of miR-1224 protects against oxidative stress-induced acute liver injury by regulating hepatocyte growth factor.

OBJECTIVE: To study the effect of microRNA-1224 (miR-1224) on hydrogen peroxide (H2 O 2 )-induced oxidative stress injury in hepatocytes, and explore its underlying mechanism. METHODS: L02 cells were treated with H2 O 2 (100 mmol/L) to establish the model of an oxidative stress injury in hepatocytes. Quantitative reverse transcriptase polymerase chain reaction was used to detect the expression of miR-1224 and hepatocyte growth factor (HGF) in L02 cells. L02 cells were transfected with anti-miR-con (H 2 O 2 + anti-miR-con group), anti-miR-1224 (H 2 O 2 + anti-miR-1224 group), pcDNA3.1 (H 2 O 2 + ctrl group), pcDNA3.1-HGF (H 2 O 2 + HGF group), si-HGF and anti-miR-1224 (H 2 O 2 + anti-miR-1224 + HGF group), si-NC and anti-miR-1224 (H 2 O 2 + anti-miR-1224 + ctrl group) by liposome method. Cells without any treatment were regarded as a negative control (NC) group. The protein expression of HGF in each group cells was detected by Western blot analysis. Cell viability and apoptosis of each group were detected by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay or flow cytometry, respectively. The interaction between miR-1224 and HGF was measured by dual luciferase reporter gene assay. RESULTS: The expression of miR-1224 was enhanced in H2 O 2 -treated L02 cells and its knockdown alleviated H 2 O 2 -induced suppression of viability and promotion of apoptosis. HGF is a target of miR-1224 and its overexpression abated H 2 O 2 -induced injury in hepatocytes. Moreover, silencing of HGF rescued the effect of downregulation of miR-1224 on cell viability and apoptosis in H 2 O 2 -treated L02 cell. CONCLUSION: Downregulation of miR-1224 could attenuate oxidative stress-induced inhibition of viability and increase of apoptosis in hepatocytes by targeting HGF, which may provide a target for potential therapy of acute liver injury.