BCL2L12: a promising molecular prognostic biomarker in breast cancer

Abstract

Objectives: BCL2-like 12 (BCL2L12) is a new member of the BCL2 gene family that was discovered and cloned by members of our group and found to be expressed in the mammary gland. Many genes of the BCL2 family were found to be implicated in breast carcinogenesis and to serve as possible prognostic markers. The aim of the present study was the quantification of BCL2L12 mRNA expression in order to assess its value as a prognostic tissue biomarker in breast cancer (BC).

Design and methods: BCL2L12 mRNA levels were determined in a statistically significant sample size of cancerous (N=108) and adjacent non-cancerous (N=71) breast tissues using a highly sensitive quantitative real-time polymerase chain reaction (qRT-PCR) method. Relative quantification analysis was conducted using the comparative C(T) (2(-ΔΔC)(T)) method, whereas the association between BCL2L12 expression and clinopathological data, disease-free survival (DFS) and overall survival (OS) were estimated by statistical analysis.

Results: BCL2L12 mRNA expression was decreased in malignant samples compared to the histologically normal counterparts (p=0.012). Significant relationships between BCL2L12 expression and TNM stages (p=0.009), metastatic potential (p=0.012), tumor size (p=0.04) and age (p=0.024) were observed. Moreover, Kaplan-Meier and Cox univariate analyses indicated that BCL2L12 expression is associated with longer DFS, whereas multivariate analysis pointed out the independent favorable prognostic value of BCL2L12.

Conclusions: According to our results, BCL2L12 mRNA expression is a favorable prognostic marker of DFS for BC patients, suggesting its possible application as a novel prognostic indicator of this malignancy.

Keywords: Apoptosis; BCL2 family; Molecular tumor markers; Prognostic biomarker; Quantitative real-time PCR.