Breast cancer is the number one cause of can- cer deaths among Hispanic women in the United States, and in Mexico, it recently became the primary cause of cancer deaths. This malign- nancy represents a poorly understood and un- derstudied disease in Hispanic women. The ELLA Binational Breast Cancer Study was es- tablished in 2006 as a multi-center study to as- sess patterns of breast tumor markers, clinical characteristics, and their risk factors in women of Mexican descent. We describe the design and implementation of the ELLA Study and provide a risk factor comparison between women in the U.S. and those in Mexico based on a sample of 765 patients (364 in the U.S. and 401 in Mexico). Compared to women in Mexico, U.S. women had significantly (p < 0.05) lower parity (3.2 vs. 3.9 mean live births) and breastfeeding rates (57.5% vs. 80.5%), higher use of oral contraceptives (60.7% vs. 50.1%) and hormone replacement therapy (23.3% vs. 7.6%), and higher family history of breast cancer (15.7% vs. 9.0%). Re- sults show that differences in breast cancer risk factor patterns exist between Mexico and U.S. women. We provide lessons learned from the conduct of our study. Binational studies are an important step in understanding disease pat- terns and etiology for women in both countries

ABSTRACT. MDR1, which is encoded by the ABCB1 gene, is involved in multidrug resistance (hydrophobic), as well as the elimination of xenotoxic agents. The association between ABCB1 gene polymorphisms ABCB1 polymorphisms in Mexican women with breast cancer and breast cancer risk in different populations has been described previously; however, the results have been inconclusive. In this study, we examined the association between polymorphisms 3435 C/T and 1236 C/T in the ABCB1 gene and breast cancer development in Mexican women according to their menopausal status and molecular classification. Molecular subtypes as well as allele and genotype frequencies were analyzed. A total of 248 women with initial breast cancer diagnosis and 180 ethnically matched, healthy, unrelated individuals were enrolled. Polymerase chain reaction-restriction fragment length polymorphism was performed to detect polymorphisms 3435 C/T and 1236 C/T in the ABCB1 gene. Premenopausal T allele carriers of the 3435 C/T polymorphism showed a 2-fold increased risk of breast cancer with respect to the reference and postmenopausal groups, as well as triplenegative expression regarding the luminal A/B molecular subrogated subtypes. In contrast, the CT genotype of the 1236 polymorphism was a protective factor against breast cancer. We conclude that the T allele carrier of the 3435 C/T polymorphism in the ABCB1 gene in combination with an estrogen receptor-negative status may be an important risk factor for breast cancer development in premenopausal women.

Introduction. Premature rupture of membranes (PRM) is a late pregnancy complication commonly associated with preterm delivery (PD).Although several markers related to the renin-angiotensin system (RAS) have been evaluated in certain pregnancy complications, only the angiotensin-converting enzyme (ACE) I/D variant has been studied in PD-PRM.The aim of this survey was to investigate the association of the polymorphisms (angiotensin II type 1 [AT1] receptor T174M and M235T, renin G2805A,ACE I/D and AT1-receptor A1166C) of the genes of RAS in women with PD-PRM. Design. Deoxyribonucleic acid samples from 89 Mexican Mestizo women with PD and PRM and 224—288 controls were studied. Polymorphisms were analysed by polymerase chain reaction-sequence specific primer assays. restricted fragment length polymorphism or sequence specific prim assays. Results. For all loci , genotype distribution was in agreement with Hardy—Weinberg expectations in the control group. Significant intergroup difference (case vs. control) was seen for angiotensinogen (AGT) M235T polymorphism, with an increased allele M235 in affected cases (50% vs. 40% in controls).Analysis of two- locus haplotype agrees with an independent segregation of physically unlinked genes. Haplotype AGT 174T-235M was also increased (50 % vs. 40% in controls). Conclusions. Physically unlinked genes involved in RAS segregate independently. The AGT 174—235 region is associated with PD-PRM in this population.

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ABSTRACT. Breast cancer (BC) is the leading cause of cancer-related deaths among women in Mexico. Two single-nucleotide polymorphisms (SNPs) in the thymidylate synthase (TS) gene, the 28-base pair (bp) 8750©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 13 (4): 8749-8756 (2014) A. Quintero-Ramos et al. tandem repeat in the TS 5'-untranslated enhanced region (TSER) and the 6-bp insertion/deletion in the TS 3'-untranslated region (TS 3'-UTR), increase the rate of misincorporation of uridylate into DNA and may lead to chromosomal damage. We examined the association between these polymorphisms and BC risk in Mexican women according to menopause status. Mexican patients with initial BC diagnosis (N = 230) and 145 individuals from a reference general population group (RGP) were included. For statistical analysis, the BC group was divided into pre-and post-menopause groups (PRE and POST groups, respectively). We analyzed both TS polymorphisms (TSER and TS 3'-UTR) using polymerase chain reaction. Finetti analysis was used to evaluate interand intra-group differences. The results showed a high frequency for the 3R and ins6 alleles in the BC, RGP, PRE, and POST groups. No significant differences were observed for the TS and TSER genotype and allele frequency distributions between groups. We found that the TSER and TS 3'-UTR SNPs are not associated with BC risk in Mexican patients.

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The polymorphisms in the genes related to angiogenesis -675 4G/5G PAI-1 and G-800A TGF-β1, segregated solely or combined, might contribute to the increased susceptibility to UCC in a Mexican population.

Background: Functional variants -173 G > C (rs755622) and -794CATT 5-8 (rs5844572) MIF gene have been associated with the risk in several types of cancer, as well as with the increase of soluble levels of MIF and TNFα. However, in previous studies contradictory and uncertain results have been presented on the implication of MIF polymorphisms with the association in cancer, specifically in breast cancer (BC). We investigated whether the variants are associated with the susceptibility to develop BC and the soluble levels of MIF and TNFα in women with BC from western Mexico. Materials and methods:A total of 152 women with BC and 182 control subjects (CS) were enrolled in this study. The determination of genotypes -173 G > C and -794 CATT 5-8 MIF polymorphisms was performed by PCR-RFLP and PCR, respectively. In addition, the soluble levels of MIF and TNFα in both studied groups were quantified by ELISA and MILLIPLEX assay, respectively. Results:The most frequent allele found in BC was the G (74.3%) and 6 (54%) in the variants -173G > C and -794 CATT 5-8 , respectively, without significant differences in both groups. Nevertheless, the women with BC carriers -173*C and -794CATT 7 have higher levels of MIF in comparison with CS. An increase of MIF (BC: 11.1 ng/mL vs CS: 5.2 ng/mL, P < .001) and TNFα (BC: 24.9 ng/mL vs CS: 9.9 pg/mL, P < .001) was found. Conclusion:The functional variants of MIF are not genetic susceptibility markers for BC. Nevertheless, the alleles -173*C and -794CATT 7 are associated with the increase of MIF circulating in women with BC.