Adams-Reyes Nishi, Coral-Vázquez Ramón M, Méndez Juan P, Tenorio Alberto, Zenteno Juan C, Villegas-Ruiz Vanessa, Canto Patricia
Obesity Research Unit, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Obesity Clinic, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.
Rev Invest Clin. 2019;71(4):237-245. doi: 10.24875/RIC.19002909.
Mitochondrial and oxidative stress has been related to obesity and breast cancer being this cancer more frequent and more aggressive in postmenopausal women with obesity.
The objective of this study was to investigate whether Mexican-Mestizo postmenopausal women with breast cancer and obesity present different somatic mutations in the mitochondrial DNA (mtDNA) when compared to women with normal body mass index (BMI).
We included six Mexican-Mestizo postmenopausal women bearing breast cancer and who underwent mastectomy or breast-conserving surgery. BMI was determined in each case. Patients' genomic DNA was isolated from blood leukocytes and tumor tissue samples. Whole mtDNA sequence was determined by MitoChip v2.0 mitochondrial resequencing array, and data were analyzed using the GeneChip Sequence Analysis Software. Tumor mtDNA sequence was compared with matched leukocyte mtDNA sequence.
Three women had a normal BMI and three presented obesity. Overall, we found 64 genetic variants: 53.1% were somatic mutations and 46.9% were polymorphisms; 44.1% were in the non-coding region and 55.9% were in genes that encode for mitochondrial proteins. Among the somatic mutations, 67.7% were in patients with normal BMI and 32.3% in patients with obesity.
We did not find a higher frequency of mitochondrial somatic mutations in postmenopausal women with breast cancer and obesity compared to those with normal BMI. However, results could be due to the small number of women studied.
线粒体和氧化应激与肥胖及乳腺癌相关，在肥胖的绝经后女性中，这种癌症更为常见且侵袭性更强。
本研究的目的是调查患有乳腺癌和肥胖症的墨西哥梅斯蒂索绝经后女性与体重指数（BMI）正常的女性相比，线粒体DNA（mtDNA）中是否存在不同的体细胞突变。
我们纳入了6名患有乳腺癌且接受了乳房切除术或保乳手术的墨西哥梅斯蒂索绝经后女性。测定了每例患者的BMI。从血液白细胞和肿瘤组织样本中分离出患者的基因组DNA。通过MitoChip v2.0线粒体重测序阵列测定整个mtDNA序列，并使用基因芯片序列分析软件对数据进行分析。将肿瘤mtDNA序列与匹配的白细胞mtDNA序列进行比较。
3名女性BMI正常，3名女性肥胖。总体而言，我们发现了64个基因变异：53.1%是体细胞突变，46.9%是多态性；44.1%位于非编码区，55.9%位于编码线粒体蛋白的基因中。在体细胞突变中，BMI正常的患者占67.7%，肥胖患者占32.3%。
与BMI正常的绝经后女性相比，我们未发现患有乳腺癌和肥胖症的绝经后女性线粒体体细胞突变频率更高。然而，结果可能归因于所研究的女性数量较少。
