IRS1 and hepatocellular carcinoma: Decreased miR-105 expression promotes the proliferation and tumorigenicity of HCC cells in vitro and in vivo and activates the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway by directly upregulating insulin receptor substrate-1, 3-phosphoinositide-dependent protein kinase-1, and AKT1, leading to decreased cyclin-dependent kinase inhibitors of 1A and 1B (p21Cip1 and p27Kip1) and increased cyclin D1 expression in HCC (16).