PTEN and diabetic kidney disease: The expression level of miRNA-22 is significantly increased during the pathogenesis of diabetic nephropathy, and miRNA-22 promotes the expression of type IV collagen (Col IV) and inhibits the autophagy of renal tubular epithelial cells by targeting phosphatase and tensin homolog (PTEN), inducing tubulointerstitial fibrosis and promoting the development of diabetic nephropathy [12].