Fig. 6

The function of PITX2 in LUAD was inhibited by miR-140-5p. a Venn diagram of microRNAs predicted to bind PITX2. b MiR-140-5p potentially targets position 135-141 of PITX2 3′UTR and the mutant type of PITX2 3′UTR was constructed. c MiR-140-5p decreased the luciferase activity of wild type PITX2 3′UTR but not mutant type (p < 0.001). d, e Ectopic expression of miR-140-5p reduced the expression of PITX2 and WNT3A in both mRNA and protein level (p < 0.001). f MiR-140-5p inhibited proliferation of LUAD cells and PITX2 restored the effect. g MiR-140-5p reduced the transcriptional activity of β-catenin (p < 0.001). h Confirmed by TUNEL assay, miR-140-5p induced apoptosis of LUAD cells, which can be rescued by PITX2. i The expression of miR-140-5p was downregulated in LUAD tissues (relative to paired normal tissues, p < 0.001). j The expression of miR-140-5p and PITX2 had a negative correlation (p < 0.0001, R = − 0.5866)