Platinum resistance accounts for much of the high mortality and morbidity associated with
ovarian cancer. Identification of targets with significant clinical translational potential remains an unmet challenge. Through a high-throughput synthetical lethal screening for clinically relevant targets using 290
kinase inhibitors, we identify
calcium/calmodulin-dependent protein kinase II gamma (CAMK2G) as a critical vulnerability in
cisplatin-resistant
ovarian cancer cells. Pharmacologic inhibition of CAMK2G significantly sensitizes
ovarian cancer cells to
cisplatin treatment in vitro and in vivo. Mechanistically, CAMK2G directly senses ROS, both basal and
cisplatin-induced, to control the phosphorylation of ITPKB at
serine 174, which directly regulates ITPKB activity to modulate
cisplatin-induced ROS stress. Thereby, CAMK2G facilitates the adaptive redox homeostasis upon
cisplatin treatment and drives
cisplatin resistance. Clinically, upregulation of CAMK2G activity and ITPKB pS174 correlates with
cisplatin resistance in human
ovarian cancers. This study reveals a key
kinase network consisting of CAMK2G and ITPKB for ROS sense and scavenging in
ovarian cancer cells to maintain redox homeostasis, offering a potential strategy for
cisplatin resistance treatment.