Targeting Phosphatidyl-inositol-4-Phosphate-5-Kinase ameliorates hepatic cancer by inhibiting PI3K/Akt/mTOR and autophagy mechanism and enhancing ROS-mediated apoptosis

Abstract

Abstract Background Hepatic cancer cells control Reactive Oxygen Species (ROS) and lipid kinases to grow. PIP5K, a lipid kinase, modulates the proliferation and Autophagy; however, its role remains HCC progression is uncertain. This study examined the involvement of PIP5K in ROS-dependent autophagy-Nrf2 antioxidant pathways using α- and β-specific isoform inhibitors (ISA201IB and IITZ01) and discovered NG-TZ-17 and 20 as inhibitors under lead optimization from IITZ01. Methods PIP5K and its relationship with the ROS-Autophagy-Nrf2 axis were examined using western blotting and IHC in Hepatocellular carcinoma (HCC) tissue samples (n = 36) and hepatic cancer cell panels. To determine the role of PIP5K in ROS-mediated apoptosis, HepG2 cells (PIP5K highly expressed cancer cells) were treated with different amounts of H2O2 with and without PIP5K inhibitors and compared to a standard autophagy inhibitor. To support in vitro cell-based data, PIP5K inhibitors (IITZ01, 60 mg/kg and NG-TZ-17, 50 mg/kg) were orally administered for 10 days in a GFP-HepG2-induced hepatic cancer model in SCID mice. Animal imaging, tumor regression, survival, and protein expression in the isolated tumors were monitored. Results PIP5K isoforms, Beclin-1, and Nrf2 increased with HCC grade. Autophagy boosted the expression of PIP5K isoforms, Nrf2, HO-1, and SOD2, preventing peroxide-induced apoptosis. Under these conditions, PIP5K inhibitors increase ROS-mediated apoptosis by downregulating proliferation, autophagy, and Nrf2, indicating that PIP5K controls cellular proliferation, autophagy, and ROS-mediated apoptosis. In vivo research showed that PIP5K inhibitors (NG-TZ-17 and IITZ01) dramatically reduced the tumor burden in HepG2-xenograft SCID mice, comparable to sorafenib. Conclusion PIP5K isoforms induced hepatic cancer cell proliferation in response to ROS. Inhibition of PIP5K isoforms sensitizes hepatic cancer cells to ROS-mediated apoptosis by decreasing the PI3K/Akt/mTOR axis, autophagy, and Nrf2.