Further study indicated that PYCR1 deficiency increased PI3K, IRS-1 and p-IRS-1 expression but decreased mTOR expression in HepG2 cells without PYCR1 expression; in addition, PYCR1 deficiency improved insulin resistance mediated by combined glucose/0.5 Gy treatment due to increases in p-Akt, IRS-1 and p-IRS-1 but a decrease in mTOR compared with the levels in HepG2 cells treated with glucose and 0.5 Gy without PYCR1 deficiency (Fig. 8c, d). This evidence concerns the gene PIK3CA and Insulin resistance.