Prognostic Value of EZH2 and Ki-67 in Squamous Cell Carcinoma of Ear and Temporal Bone

The objective of this study was to retrospectively evaluate the expression of EZH2 and Ki-67 and their role in the prediction of outcomes in a cohort of Ear and Temporal Bone Squamous Cell Carcinoma (ETBSCC) patients in a tertiary medical center.

Immunohistochemical EZH2 and Ki-67 expression was evaluated, and univariate and multivariate analyses were performed in 43 ETBSCC patients. The Kaplan-Meier method was used to plot survival curves. Cox regression analysis was used to investigate an independent prognostic factor.

EZH2 protein was overexpressed in almost 70% of the patients, and higher expression of Ki-67 was detected in more than 50% of the patients. The overexpression of either EZH2 or Ki-67 was significantly correlated with tumor T stage. Moreover, a significant positive correlation between the EZH2 and Ki-67 expression levels was detected. Higher expression of EZH2 or Ki-67, advanced T stage, positive surgical margin, and identified PNI were significantly predictive of a worse prognosis for the 5-year overall survival rate. Higher expression of Ki-67 and advanced T stage were confirmed to be independent prognostic factors. Moreover, patients with higher expression of EZH2 and Ki-67 simultaneously had a worse prognosis.

Our study demonstrated that the overexpression of EZH2 was significantly associated with advanced tumor stage and poor 5-year overall survival in a Chinese ETBSCC cohort. These findings highlight the applicability of EZH2 as a candidate therapeutic target for integrated therapies. Further exploration and validation through a stable cell line are needed.