Altogether, these results combined with previous studies conclude that metformin exerts its anti-cancer properties in part through inducing miRNAs such as miR-2110, miR-132-3p, miR-222-3p and miR-589-3p to directly target genes including PIK3R3 and STMN1, and thereby regulates signalling pathways such as PI3K-Akt and MAPK/ERK. This evidence concerns the gene PIK3R3 and cancer.