Bromine domain protein 4 is an important marker for prognosis of ovarian cancer and tumor immune infiltration

Background: Ovarian cancer (OC) is one of the most common malignant gynecological tumors, but its pathogenesis is unclear. Bromine domain protein 4 (BRD4) is involved in the malignant transformation of cells, as well as the invasion and metastasis of tumor cells. The biological role of BRD4 in ovarian cancer is yet to be determined. Methods The differential expression of BRD4 in OC and corresponding normal tissues was evaluated by exploring the Tumor Immune Assessment Resources (TIMER) and the Oncomine database. The correlation between the expression level of BRD4 and the prognosis of OC patients was evaluated using the Kaplan-Meier Plotter database. Using TIMER, we further studied the correlation between BRD4 and tumor immune cell infiltration. Results The expression of BRD4 was significantly higher in patients with OC, and high BRD4 expression was closely related to low overall survival rate. The BRD4 expression was associated with the levels of immune markers of macrophages, dendritic cells, neutrophils, and various effector T cells. Taken together, these findings show that BRD4 expression is significantly related to immune infiltration in OC and suggest that BRD4 might play an important role in the immune evasion of OC cells. Conclusion The expression level of BRD4 in OC tissues is significantly upregulated, and its high expression is significantly associated with poor prognosis of patients and is closely related to tumor immune infiltration. These results suggest that BRD4 can be used as a prognostic marker and a marker of immune infiltration in OC.