ZNF865 as a novel molecular target for cancer treatment

Despite the advancements and increased availability of conventional cancer therapies, there is a need for strategies to enhance treatment, prolong survival, and prevent recurrence and resistance. Gene therapies can address the limitations of traditional anti-cancer therapies to improve outcomes. Modulation of cancer-related genes has shown promising results. Identifying specific proteins and pathways that drive cancer cell proliferation and survival as molecular targets is fundamental for cancer gene therapy. ZNF865 is a 1056 amino acid-long protein with 20 unique ZNF and two transactivation domains identified by our team [1]. Even though ZNF865 is widely expressed in all cell types, the function of this protein is not fully known. We have demonstrated that the expression of ZNF865 affects the viability and proliferation of multiple cell types, and that upregulation of ZNF865 leads to the repair of DNA damage, while downregulation leads to rapid DNA damage accumulation, which pushes cells into and out of senescence. DNA damage/cellular senescence is recognized as a key tumor-suppressor mechanism in cancer. A dramatic decrease in cell proliferation capacity in ZNF865 downregulated cells suggests that this protein may be a molecular target for cancer. Survival analysis of lung and esophageal cancers showed a correlation between ZNF865 expression and survival probability. The purpose of this study is to investigate the role of ZNF865 in cancer cell proliferation and invasion. For this, ZNF865 was knocked down in lung adenocarcinoma cells (A549) with CRISPRi using the lentivirus system. The ZNF865 downregulated cells were sorted with flow cytometry. The proliferation of the cells was assessed using colony formation assay. The cells were allowed to proliferate for 14 days. The changes in the invasive potential of the cells were assessed using scratch assay for 48 h. Apoptosis rates of the cells were determined using Annexin-V/PI analysis, and the cell cycle phase distributions of the cells were analyzed by flow cytometry. The toxicity of cisplatin was tested using CCK8 viability assay. The ZNF865 knockdown resulted in approximately 90% decrease in clonogenic survival of the lung cancer cells (p<0.001). The gap closure in scratch assay was inhibited by 35% in the ZNF865 downregulated cells compared to the non-target control at 24 h (p<0.001). Apoptosis rates, cell cycle phase distributions, and cisplatin toxicity were not significantly affected by inhibition of ZNF865 expression, indicating alternate molecular mechanisms of action. Our findings suggest that silencing ZNF865 gene inhibited proliferation and decreased the invasion rate of the A549 cells, indicating ZNF865 may be a therapeutic target for lung cancer treatment. Future studies include validating the effect of ZNF865 downregulation on cancer proliferation and invasion in additional cancer cell types. 1. Lewis, C., et al., ZNF865 (BLST) Regulates Human Cell Senescence and DNA Damage. 2025.