Gamboa-Loira Brenda, Cebrián Mariano E, Salinas-Rodríguez Aarón, López-Carrillo Lizbeth
Instituto Nacional de Salud Pública, Av. Universidad 655, Col. Santa María Ahuacatitlán, C.P. 62100, Cuernavaca, Morelos, Mexico.
Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, Del. Gustavo A. Madero, C.P. 07360, Ciudad de México, Mexico.
Environ Toxicol Pharmacol. 2017 Dec;56:106-113. doi: 10.1016/j.etap.2017.08.032. Epub 2017 Sep 8.
To evaluate whether the association between breast cancer (BC) and inorganic arsenic (iAs) exposure is modulated by selected polymorphisms in iAs metabolism.
A population based case-control (1016/1028) study was conducted in Northern Mexico. Urinary arsenic metabolites were measured by High Performance Liquid Chromatography. Metabolites percentages and methylation ratios, were estimated. Genotypes of selected polymorphisms were determined by allelic discrimination. The interaction between polymorphisms and iAs metabolites percentages and methylation ratios on BC was assessed with unconditional logistic regression models.
A significant interaction (p=0.002) between MTR c.2756A>G polymorphism and percentage dimethylarsinic acid (DMA) on BC was found; BC risk related with %DMA was lower in AG+GG carriers than in AA carriers. No other significant interactions were found.
MTR c.2756A>G polymorphism may confer protection for BC associated with iAs exposure. Further research is warranted to elucidate the potential involvement of other polymorphisms in iAs-related BC.
评估乳腺癌（BC）与无机砷（iAs）暴露之间的关联是否受iAs代谢中特定多态性的调节。
在墨西哥北部进行了一项基于人群的病例对照研究（1016/1028）。通过高效液相色谱法测量尿砷代谢产物。估算代谢产物百分比和甲基化率。通过等位基因鉴别确定所选多态性的基因型。使用无条件逻辑回归模型评估多态性与iAs代谢产物百分比和甲基化率对BC的相互作用。
发现MTR c.2756A>G多态性与二甲基砷酸（DMA）百分比之间在BC上存在显著相互作用（p=0.002）；AG+GG携带者中与%DMA相关的BC风险低于AA携带者。未发现其他显著相互作用。
MTR c.2756A>G多态性可能为与iAs暴露相关的BC提供保护。有必要进一步研究以阐明其他多态性在iAs相关BC中的潜在作用。
