Down-regulation of BACH2 in formalin-fixed paraffin-embedded breast cancer tissue as transcriptional regulation in cancer

Abstract

Introduction: Breast cancer is one of the main causes of mortality in women. BACH2 gene is required in regulating the development and function of diverse immune cell types (B and T cell, macrophage). The BACH2 gene is a prominent susceptibility locus for multiple autoimmune and allergic diseases. Nevertheless, the expression and potential function of BACH2 in breast cancer stay unclear. Therefore, this study was performed with aim to evaluate BACH2 gene expression in breast tumor samples. Methods: In this case-control study which used paraffin tissues of breast cancer to evaluate gene expression, 40 formalin-fixed paraffin embedded (FFPE) tumoral of breast cancer and 40 healthy tissue provided from pathology department of Al-Zahra Hospital in Isfahan were enrolled. The samples of paraffin blocks were prepared during 2014 to 2015. After completing the consent form, the clinical information for all samples were taken. Total RNA was extracted and complementary DNA (cDNA) was synthesized. The relative gene expression was determined using quantitative method of real-time RT PCR (qRT-PCR) and was evaluated by method. Data were analyzed by SPSS software (version 22) and t-test and ANOVA. P<0.05 was considered significant. Results: The expression of BACH2 gene was significantly lower in tumor tissue compared to healthy tissue adjacent (P < 0.05). Also, the expression of this gene in metastatic state showed significant decrease (P=0.029). Conclusion: The expression of BACH2 is lower in breast cancer tumoral tissue than the healthy tissue. Considering the BACH2 gene function, it can be suggested as tumor suppressor in breast cancer. Furthermore, the results show down-regulation in metastatic samples, which indicates the role of gene in suppressing the metastasis pathways.

Keywords

• bach2 gene
• breast cancer
• real-time pcr
• transcriptional regulation