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

The renin-angiotensin system (RAS) is a hormonal signaling mechanism widely known as a blood pressure regulation system. The classic pathway begins with the release of renin (REN), an aspartyl-protease that cleaves angiotensinogen (AGT) to produce angiotensin I (AngI), which is later hydrolyzed by the angiotensin I-converting enzyme (ACE) to produce angiotensin II (AngII); this octapeptide exerts its functions through its specific receptors, angiotensin II receptor type 1 and type 2 (AGTR1 and AGTR2 respectively). 1 Most of the physiological effects such as blood vessel constriction have been attributed to the AGTR1 signaling pathway. In recent years, however, research papers have described mitogenic and angiogenic activities as well, activities that are also mediated through AGTR1. 2,3 Since angiogenesis and proliferative processes are related to the development, progression and metastasis of cancer, it is reasonable to believe that RAS may have a role in cancer. 4 When ACE insertion-deletion (indel) polymorphism was examined as a cancer risk marker, it was associated with gastric, endometrial, prostate and breast cancer. [5][6][7][8][9][10][11][12][13] However, three different AGTR polymorphisms presented contradictory results when studied for breast cancer. [13][14][15] For every biological system each component contributes to the overall effect; therefore, to explain any phenomenon, a more integrated approach is needed. To date, no study has included more than two RAS genes. With this in mind, in the present work we explored the association between breast cancer and some of the major polymorphisms of the four Abstract Recent information has revealed new roles in the angiogenic processes linked to the rennin-angiotensin system. To date few studies have been done on the association between RAS genes and cancer and the majority focus mainly on angiotensin I-converting enzyme (ACE). For breast cancer there are three reports that include the angiotensin II receptor, subtype 1 (AGTR1), only one for angiotensinogen (AGT) and none for renin gene (REN). In the present study we investigate whether REN (BglI), AGT (M235T), ACE (A245T, Indel), and AGTR1 (A1166C) are associated with breast cancer. Polymorphisms were analysed by PCR and RFPLs or sequence specific assay in three groups: breast cancer, benign breast disease (BBD) and general population. REN polymorphism shows that homozygous for A allele have an increased risk for BBD. Differences in M235T genotype frequencies were significant with less heterozygous in breast cancer. With different risk values ACE indel was associated with BBD and breast cancer. Association of AGTR1 was observed only in the breast cancer group, where C allele carriers present a reduced risk. Results of this work supports previous observations on the possible involvement of this system in breast cancer but it also suggests a role in benign disease.

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. Prostate cancer is one of the most common malignant neoplasias in developed countries. In 2003, 6,536 new cases and 4,602 related deaths were reported in Mexico. The renin-angiotensin system has been shown to play a role in prostate cancer pathology. Two previous studies investigated the association of prostate cancer with the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene; both studies reported an association between prostate cancer and the DD genotype. The present study was aimed at searching for an association of prostate cancer and benign prostatic hyperplasia with the I/D polymorphism in the ACE gene and the A1166C polymorphism in the angiotensin type 1 receptor (AGT1R) gene and at comparing allele frequencies between both groups and the general population. Materials and methods. DNA was extracted from 20 samples from individuals with a prostate cancer diagnosis and from 20 samples from individuals with a benign prostatic hyperplasia diagnosis. Genotyping was performed by PCR-RFLP analysis. Polymorphism frequency results obtained for the test groups were compared with the frequencies in 66 individuals from the general population, which were previously obtained at the same molecular medicine laboratory in the context of other studies.Results. The comparative analysis of the three groups revealed significant differences for allele frequencies in the two genes in patients groups (prostate cancer and benign prostatic hyperplasia) versus the general population. The D allele in the ACE gene was closely associated with a significant higher risk of developing both benign prostatic hyperplasia (odds ratio [OR]