Human Epidermal Growth Factor Receptor-2 gene polymorphism and breast cancer risk in women from the Northeastern region of Brazil

Carla Solange Escórcio-Dourado,Francisco Adelton Alves-Ribeiro,Jose Charles Lima-Dourado,Alesse Ribeiro Dos Santos,Renato De Oliveira Pereira,Cleciton Braga Tavares,Vladimir Costa Silva,Pedro Vitor Lopes Costa,José Maria Soares-Júnior,Benedito Borges Da Silva

doi:10.6061/clinics/2020/e2360

Abstract

OBJECTIVES:In the Human Epidermal Growth Factor Receptor-2 (HER2) rs1136201 variant, the presence of the G allele may promote cellular alterations and increase breast cancer risk, in addition to enhanced cellular proliferation, tumor aggressiveness, and metastases. The aim of this study was to investigate the presence of the single-nucleotide polymorphism (SNP) variant, rs1136201, within the HER2 gene in women from the Northeastern region of Brazil and breast cancer risk.METHODS:The study included 140 women who were divided into two groups, case (breast cancer) and control (without breast cancer), with 70 women in each group. Peripheral blood of each woman was drawn for the study of genomic Deoxyribonucleic acid (DNA) extracted from leukocytes using the genotyping technique by real-time polymerase chain reaction.RESULTS:The GG genotype occurred in 1 woman in both groups (1.4%) (p=0.32), while the AG genotype occurred in 19 (27.2%) and 13 (18.6%) women in the case and control (p=1.00) groups, respectively. No statistically significant difference in GG and AG genotypes was observed between the case and control groups in premenopausal women (p=1.00). Furthermore, no significant difference in genotypes was observed between the groups, among postmenopausal women (p=0.14).CONCLUSION:In this study, the HER2 rs1136201 polymorphism did not show any statistically significant association with breast cancer, both in premenopausal and postmenopausal women. Nevertheless, further studies with a larger sample size should be performed to assess the association of HER2 polymorphism with breast cancer risk in women from the Northeastern region of Brazil.

Highlights

Breast cancer is a neoplasm that most commonly affects women worldwide, with an estimate of 2,088,849 new cases and 626,679 deaths in 2018 based on GLOBOCAN 2018 [1]
Women older than 80 years and patients suffering from liver, metabolic, cardiovascular, kidney disease or those reporting other types of malignancies were excluded from the study
Genotype frequencies of the rs1136201 variant of the human epidermal growth factor receptor 2 (HER2) gene conformed to Hardy–Weinberg equilibrium

Summary

Introduction

Breast cancer is a neoplasm that most commonly affects women worldwide, with an estimate of 2,088,849 new cases and 626,679 deaths in 2018 based on GLOBOCAN 2018 [1]. Breast cancer incidence is higher in the most developed country of the world compared to underdeveloped countries [2,3]. In Brazil, following non-melanoma skin cancer, breast cancer is the most common malignancy in women, with an estimate of 59,700 new cases and 16,927 deaths in 2019 [4]. Received for publication on August 24, 2020. Accepted for publication on October 23, 2020

Objectives

Methods

Results

Conclusion