Environmental Contaminants Modulate Breast Cancer Development and Outcome in TP53 p.R337H Carriers and Noncarriers

Area of Science:

• Environmental Health
• Oncology
• Genetics

Background:

• Paraná state, South Brazil, faces significant cancer concerns from environmental pollution and a prevalent TP53 p.R337H germline variant.
• Subregions C1 (rural), C2 (rural), and C3 (industrialized) were previously classified based on geochemical, agricultural, and population density factors.
• Region C2 exhibits lower organochloride and chlorine anion levels, reduced agricultural output, and less industrial activity compared to C1 and C3.

Purpose of the Study:

• To assess breast cancer (BC) risk in relation to environmental factors and the TP53 p.R337H variant across different subregions of Paraná.
• To investigate the influence of environmental conditions on BC prevalence, risk, and mortality rates in women.

Main Methods:

• TP53 p.R337H carrier status was determined in 4658 women aged over 30 years from subregions C1, C2, and C3 (Group 1).
• Breast cancer risk was analyzed in relation to TP53 p.R337H status within the study population.
• Breast cancer mortality rates and risks were examined in 8181 deceased women aged over 30 years across the subregions (Group 2).

Main Results:

• Breast cancer risk was 4.58 times higher among TP53 p.R337H carriers.
• Breast cancer prevalence and risk were significantly lower in subregion C2 compared to C3.
• Mortality rates and risks associated with breast cancer were lower in C2 compared to both C3 and C1.

Conclusions:

• Environmental factors appear to modulate breast cancer risk and outcomes in both TP53 p.R337H carriers and non-carriers.
• The findings highlight the interplay between genetic predisposition and environmental exposures in breast cancer development and progression in Paraná.