Genomic instability association with intracellular aluminum concentration in breast tumors

Author(s)

Raquel Mary Rodrigues Peres

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Ciências Médicas
• Defense date: 2013-07-30

Examining board members

Luís Otávio Zanatta Sarian; Lucia Costa Paiva; Luiz Carlos Zeferino; Ana Elizabete Silva; Jurandyr Moreira de Andrade

• Advisor: Luís Otávio Zanatta Sarian

Abstract

Introduction: It has long been hypothesized if the effects of aluminum on human cells may have clinical implications, especially regarding to breast cancer. The current laboratorial evidence showing higher levels of aluminum in breast tissues and the known biological effects of this metal, are not sufficient to establish a causal relationship between aluminum exposure and increased risk of developing breast cancer. The objective of this study was to establish the aluminum concentration in the central and peripheral areas of breast tumors as well as in normal glandular area of the breast and to correlate these findings with the instability of ERBB2, C-MYC and CCND1, and aneuploidy of chromosomes harboring these genes. Methods: This study included 176 women diagnosed with invasive breast carcinoma with tumors larger than 1cm3 without neoadjuvant chemotherapy, operated between 2008 and 2010 at the Women's Hospital Professor. Dr. José Aristodemo Pinotti - Centro de Atenção Integral à Saúde da Mulher (CAISM) - UNICAMP. To analyze the intracellular concentration of aluminum, samples from 150 patients were considered viable; for the analysis of genomic instability as a function of the concentration of aluminum, 118 samples were considered viable. These figures define the sample of each of the two articles that this PhD thesis comprises. Evaluation of tissue aluminum content was carried out using Graphite Furnace Atomic Absorption Spectrometry (GFAAS). A TMA slide containing the tumor and normal samples was used in FISH assays to assess ERBB2, C-MYC and CCND1 and the respective chromosomes 17, 8 and 11 centromeres status. Clinicopathological data were obtained from patients' records. Results: The average aluminum content found in breast was 1.88 mg/kg in the central tumor areas, 2.10 mg/ kg in the peripheral tumor areas and 1.68 mg/ kg in the normal tissue areas. The amplification and/or aneuploid status for the ERBB2/CEP17, C-MYC/CEP8 and CCND1/CEP11 was detected in 24%, 36.7% and 29.3% of the tumors, respectively. The average aluminum content in tumor areas (either central or peripheral) was not significantly different from that in normal tissues. We found that aluminum concentration was not related to any of the gene status. Conclusions: We consider important that in vitro experimental studies continue to be done in order to elucidate the possible effects of aluminum in the development of breast tumors, whether it is influencing the tissue microenvironment or other genome stability pathways (AU)

• FAPESP's process: 09/06148-4 - Genomic instability in breast malignant tumors as related to the concentration of intracelular aluminium and to estrogen receptor status
• Grantee: Raquel Mary Rodrigues Peres
• Support Opportunities: Scholarships in Brazil - Doctorate