The Prognostic Value of the Chromobox Family in Human Ovarian Cancer

Ovarian cancer is one of the most lethal gynecologic tumors in women and has a poor prognosis. The purpose of our study was to identify new prognostic markers in ovarian cancer. We examined the prognostic roles of mRNA expression of the chromobox (CBX) family in patients with ovarian cancer utilizing the Kaplan-Meier plotter database. The prognostic values and expression levels of CBX members associated with prognosis were further evaluated using KM plotter in diverse subgroups and immunohistochemistry (IHC) analysis in ovarian carcinoma. The results revealed that elevated CBX1-3 mRNA expression may predict poor overall survival (OS) and progression-free survival (PFS) outcomes in patients with ovarian cancer. Notably, in women with ovarian cancer, increased CBX1 mRNA expression was linked to a short OS in all stages and in the grade II and grade III subgroups. Additionally, CBX2 and CBX3 were strongly related to short OS in stage III+IV patients, and a link between high CBX3 mRNA expression and unfavorable OS in grade II patients was observed. High expression levels of CBX1 and CBX3 were significantly associated with chemotherapy resistance in ovarian cancer patients. IHC staining showed that the CBX1-3 proteins were upregulated in serous ovarian carcinoma tissues compared with normal ovarian tissues. Therefore, our results indicated that CBX1-3 could be attractive biomarkers for predicting poor prognosis of ovarian cancer.