Fig. 4

miR-493 enhences the sensitivity of lung cancer cells to cisplatin by targeting TCRP1. a Schematic of predicted miR-493 site in the 3’UTR of human TCRP1 mRNA, which broadly conserved among vertebrates. b miR-493 stable transfection reduces the TCRP1 mRNA levels. c Enforced expression miR-493 inhibits TCRP1 protein level and Akt signal pathway. d Luciferase assay of A549 and A549/DDP cells, which were co-transfected with miR-493 and a luciferase reporter containing full lengthTCRP1 3′-UTR (wt 3′-UTR) or a mutant (mut 3′-UTR) in which the nucleotides of the miR-493-binding site were mutated. An empty luciferase reporter construct was used as a negative control (scramble). The luciferase activities were measured 48 h post transfection. miR-493 markedly suppressed the luciferase activity in Luc-wt reporter constructs. The data are the means ± s.e.m. for separate transfections (n = 3). *P < 0.05 versus scramble. e MTS assay indicated that overexpression of exogenous TCRP1 (without 3’-UTR of TCRP1) rescued upon the sensitization induced by miR-493 in cells. f exogenous expression of TCRP1 attenuates DNA damage induced by miR-493 in lung cancer cells. Immunofluorescence staining was performed to examine γ-H2AX foci formation. γ-H2AX foci were counted in 5 random 200× micro fields under fluorescence microscope. Representative images of the assays are shown. Original magnification: ×200.Significant differences are indicated, (*, P < 0.05). g, h A549 or 549/DDP cells were treated with neither 2 uM 5-AZA or DMSO for 72 h, next treated with miR-493 inhibitor (RiboBio Co., Ltd) or scrambled control for 24 h, the mRNA and protein expression of TCRP1 were detected