CARD9 contributes to ovarian cancer cell proliferation, cycle arrest, and cisplatin sensitivity.

Background: Ovarian cancer recurrence and chemotherapy resistance are still urgent issues, and exploring the mechanisms of metastasis and chemotherapy resistance is beneficial to the development of therapeutic methods. Caspase recruitment domain family member 9 (CARD9) and homeobox B5 (HOXB5) are related and both are upregulated in ovarian cancer. This study aimed to define their functions in ovarian cancer cell proliferation, migration, and cisplatin sensitivity.

Results: The levels of CARD9 were detected in acquired ovarian cancer tissues and cell lines. CARD9 was indeed abnormally upregulated in them. CARD9 knockdown significantly suppressed cell proliferation, colony formation, migration, cycle arrest, and cisplatin sensitivity. HOXB5 bound to the CARD9 promoter, and HOXB5 overexpression reversed the regulation by CARD9 knockdown in cells, as well as the activation of NF-κB signaling. This indicated that CARD9 was positively regulated by HOXB5 in ovarian cancer cells.

Conclusion: Together, CARD9 is involved in ovarian cancer cell proliferation, migration, and cisplatin sensitivity via NF-κB signaling after transcriptional activation by HOXB5.