Expressions of ETS2 in colorectal cancer tissues and its clinical significance

Objective To investigate the expressions of ETS2 (E-twenty six 2) in colorectal cancer tissues, analyze the relationships between clinic-pathological parameters and ETS2 expression, and evaluate its clinical prognostic value. Methods We collected fresh colorectal cancer, paracancerous and the corresponding normal tissues, and specimens of paraffin of colorectal cancer and adjacent to carcinoma. Real-time fluorescent quantitative PCR and immunohistochemistry were used to detect ETS2 mRNA expression and protein expression respectively. Results Our results showed that the expression of ETS2 mRNA in colorectal cancer tissues was significantly higher than that in adjacent and normal tissues (P 0.05). Immuno-histochemical results showed that ETS2 was expressed in 52.07% (63/121) colorectal cancer tissues, but only in 13.04% (6/46) para-cancerous tissues, showing a significant difference (P<0.05). ETS2 expression was closely associated with tumor differentiation, invasion depth, lymph node metastasis, and MMR status (all P<0.05). ETS2 expression was associated with postoperative progression-free survival in patients with colorectal cancer (P<0.001). Multivariate regression analysis using Cox model showed that ETS2 expression (HR: 0.461, 95% CI: 0.271~0.683, P=0.003) and infiltration depth (HR: 0.352, 95% CI: 0.113~0.769, P=0.015) were independent prognostic factors for postoperative progressive-free survival of colorectal cancer patients. Conclusion Compared with para-cancerous tissues, ETS2 was overexpressed in transcriptional and translational levels of colorectal cancer. Moreover, ETS2 was a potential marker for predicting postoperative progression-free survival in patients. Key words: Colorectal neoplasms; Prognosis; ETS2; Infiltration depth; Marker