Megha J Pandya, Jessica Hoffman, Achuth Padmanabhan
ZNF217 is a potent oncogene that drives ovarian cancer progression and therapeutic resistance. We show that ZNF217 overexpression markedly increases ERBB2 levels in ovarian cancer cells, suggesting its potential as a biomarker to identify ovarian tumors that will respond to ERBB2-targeted therapeutics. Unexpectedly, ZNF217-high ovarian cancer cells exhibit resistance to multiple ERBB2 inhibitors, revealing a disconnect between receptor abundance and drug sensitivity. Mechanistically, ZNF217 drives chemoresistance by elevating the expression of several key receptor tyrosine kinases, most notably AXL, that activates MAPK signaling. Further, ZNF217 also upregulates ERK1/2 levels in ovarian cancer cells. This induces rewiring of downstream signaling, promoting an ERK-dominant state that sustains survival despite ERBB2 inhibition. Therapeutic targeting of the AXL-ERK axis reduced cell viability and metastatic potential in vitro, while suppressing tumor burden and prolonging survival in xenograft models. Thus, by elevating the expression of several key signaling receptors and their downstream effectors in ovarian cancer cells, ZNF217 establishes signaling plasticity that defines a novel mechanism of chemoresistance. These findings identify ZNF217 as a key determinant of signaling state and drug response and provides rationale to evaluate targeting AXL and ERK signaling in ZNF217-high ovarian tumors.