Background: The zinc finger protein 587B (ZNF587B ) is a novel cisplatin-sensitive gene that was identified in our previous research by using a genome-scale CRISPR-Cas9 knockout library in ovarian cancer (OC) cell lines. ZNF587B  belongs to the C2H2-type zinc finger protein (ZFP) family. Many ZFP protein could inhibit tumor development and malignancy. However, the function of ZNF587B  remains unknown.
Methods: Quantitative PCR (qPCR) was utilized to compare ZNF587B  mRNA expression levels in OC and normal ovarian cell lines. The small interfering RNA (siRNA) and full-length ZNF587B eukaryotic expression plasmid were constructed and transfected into OC cells later. Colony formation, 5-ethynyl-2′-deoxyuridine (EdU) assay, transwell assay, and xenograft experiment were conducted to evaluate the effect of ZNF587B  on OC cells.
Results: ZNF587B  was downregulated by approximately 43% and 17% in the OC cell lines SKOV3 and A2780, respectively, compared with that in the normal ovarian cell line IOSE80. Overexpression of ZNF587B  reduced cell proliferation, colony formation, migration, and invasion, which could be reversed by knockdown of ZNF587B via siRNA. Xenograft experiments also confirmed that ZNF587B  could suppress tumor growth. Survival data of OC patients in the SurvExpress database showed that with respect to overall survival, low-risk patients grouped by the prognostic index had a higher expression of ZNF587B  and a better prognosis than high-risk group (HR = 1.77, 95% CI: 0.55– 0.70, p = 0.023). Moreover, overexpression of ZNF587B promoted OC cells apoptosis when pretreated with cisplatin.
Conclusion: ZNF587B  is a novel potential tumor suppressor of OC and may be a therapeutic target for OC.
Keywords: ZNF587B, C2H2-type zinc finger protein, proliferation, metastasis, ovarian cancer