19 research outputs found

    Losartan Slows Pancreatic Tumor Progression and Extends Survival of SPARC-Null Mice by Abrogating Aberrant TGFβ Activation

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    Pancreatic adenocarcinoma, a desmoplastic disease, is the fourth leading cause of cancer-related death in the Western world due, in large part, to locally invasive primary tumor growth and ensuing metastasis. SPARC is a matricellular protein that governs extracellular matrix (ECM) deposition and maturation during tissue remodeling, particularly, during wound healing and tumorigenesis. In the present study, we sought to determine the mechanism by which lack of host SPARC alters the tumor microenvironment and enhances invasion and metastasis of an orthotopic model of pancreatic cancer. We identified that levels of active TGFβ1 were increased significantly in tumors grown in SPARC-null mice. TGFβ1 contributes to many aspects of tumor development including metastasis, endothelial cell permeability, inflammation and fibrosis, all of which are altered in the absence of stromal-derived SPARC. Given these results, we performed a survival study to assess the contribution of increased TGFβ1 activity to tumor progression in SPARC-null mice using losartan, an angiotensin II type 1 receptor antagonist that diminishes TGFβ1 expression and activation in vivo. Tumors grown in SPARC-null mice progressed more quickly than those grown in wild-type littermates leading to a significant reduction in median survival. However, median survival of SPARC-null animals treated with losartan was extended to that of losartan-treated wild-type controls. In addition, losartan abrogated TGFβ induced gene expression, reduced local invasion and metastasis, decreased vascular permeability and altered the immune profile of tumors grown in SPARC-null mice. These data support the concept that aberrant TGFβ1-activation in the absence of host SPARC contributes significantly to tumor progression and suggests that SPARC, by controlling ECM deposition and maturation, can regulate TGFβ availability and activation

    The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer

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    Abstract: Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM−/− patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (OR = 2.44, P = 0.034 and OR = 3.79; P = 0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (OR = 1.96; P = 0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors

    Análise de Política Externa e Política Externa Brasileira: trajetória, desafios e possibilidades de um campo de estudos

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    Association of a Culturally Defined Syndrome (Nervios) with Chest Pain and DSM-IV Affective Disorders in Hispanic Patients Referred for Cardiac Stress Testing

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    Background: Hispanics have a high prevalence of cardiovascular risk factors, most notably type 2 diabetes. However, in a large public hospital in Houston, Texas, Hispanic patients referred for cardiac stress testing were significantly more likely to have normal test results than were Whites or non-Hispanic Blacks. We undertook an exploratory study to determine if nervios, a culturally based syndrome that shares similarities with both panic disorder and anginal symptoms, is sufficiently prevalent among Hispanics referred for cardiac testing to be considered as a possible explanation for the high probability of a normal test result. Methods: Hispanic patients were recruited consecutively when they presented for a cardiac stress test. A bilingual interviewer administered a brief medical history, the Rose Angina Questionnaire (RAQ), a questionnaire to assess a history of nervios and associated symptoms, and the PRIME-MD, a validated brief questionnaire to diagnose DSM-IV defined affective disorders. Results: The average age of the 114 participants (38 men and 76 women) was 57 years, and the average educational attainment was 7 years. Overall, 50% of participants reported a history of chronic nervios, and 14% reported an acute subtype known as ataque de nervios. Only 2% of patients had DSM-IV de®ned panic disorder, and 59% of patients had a positive RAQ score (ie, Rose questionnaire angina). The acute subtype, ataque de nervios, but not chronic nervios, was related to an increased probability of having Rose questionnaire angina (P5.006). Adjusted for covariates, a positive history of chronic nervios, but not Rose questionnaire angina, was signi®cantly associated with a normal cardiac test result (OR52.97, P5.04). Conclusion: Nervios is common among Hispanics with symptoms of cardiac disease. Additional research is needed to understand how nervios symptoms differ from chest pain in Hispanics and the role of nervios in referral for cardiac workup by primary care providers and emergency room personnel

    Evidence for Paleoindians in Wisconsin and at the Skare Site

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