Many of the investigations in this genetic epidemiology project arise from observations in families at high risk of cancer or in other etiologic studies. A pilot study to follow-up patients from a case-control study of 718 non-Hispanic white patients with cutaneous melanoma from melanoma clinics in Philadelphia and San Francisco is being planned. Questionnaire data, tumor, and DNA from a case-control study of 183 incident melanoma cases and 179 controls conducted in North-Eastern Italy were used to evaluate the melanocortin-1 receptor (MC1R) gene, the major regulator of human pigmentation, and somatic mutations of the BRAF oncogene. In subjects with melanoma arising on sun exposed areas of the body and with limited chronic solar damage, we found a strong association between MC1R germline variants and melanoma with somatic mutations in the BRAF oncogene. We confirmed this association in an independent population. Data from other Italian populations have been collected to extend the analyses of association between melanoma risk and pigmentation and immune-related genes;evaluation of these additional populations is in process. One of the potential pathways that leads to the development of melanoma includes the loss of regulation of common melanocytic nevi, which acquire atypic or dysplastic characteristics that can further evolve in neoplasia. To study this pathway, we are currently collecting multiple tissue samples of normal skin, common melanocytic nevi, dysplastic nevi, melanoma and metastasis from melanoma from the same subjects from North-Eastern Italy. We extended the collection to another Italian site (LAquila) to increase the statistical power for analyses. Unfortunately most of the material collected at LAquila was destroyed during the devastating 2009 LAquila earthquake. We are planning to study the expression and presence of mutations in multiple genes of the cell cycle, telomere, and transduction pathways in the serial tissue samples and germline DNA to explore the mechanisms involved in melanoma development through nevi. Relatives of 365 of the glioma cases from a DCEG comprehensive case-control study of adults with brain tumors were interviewed about personal/family medical history and other risk factors. Analyses to examine the risk of cancer among the first degree relatives compared to population controls have been completed;write-up of the results is in process. Examination of questionnaire data from a retrospective single institution study of childhood medulloblastoma showed little evidence for increased cancer risks among relatives of medulloblastoma patients. Chordoma is a rare primary malignant bone tumor that arises mainly in the axial skeleton from rests of embryonic notochordal stem cells that failed to undergo normal regression. We are collaborating with the Department of Radiation Oncology, Massachusetts General Hospital, Boston, to identify chordoma families to help map and identify a chordoma susceptibility gene. The project involves obtaining personal and family medical history, buccal cells and slides of tumor tissue from the subgroup of patients most likely to have a genetic predisposition to chordoma: those diagnosed with chordoma <18 years. During the past year we completed enrollment of 55 chordoma patients. We are in the process of obtaining personal and family medical history, buccal cells and tumor tissue from them. In addition we are preparing an amendment to this protocol to expand the study to include 150 additional patients diagnosed with chordoma at any age and site. In collaboration with Yale University Tissue Microarray (TMA) core facility, we have successfully built TMAs of 1,500 invasive tumors collected from the Polish Breast Cancer Study. We have immunohistochemically (IHC) stained a subset of these tumors (N=842) for 18 molecular markers involved in hormone biosynthesis, metabolism, and receptor mediated pathways. Analyses of these markers suggest that risk factors for breast cancer may vary by molecular subtypes and by hormone pathways characterized by co-expression of the hormonal markers. We have also stained all TMAs for six markers (ER-alpha, ER-beta, PR, HER2, EGFR, and CK5) using a newly developed Automated Quantitative Analysis (AQUA). Comparison of the two approaches (AQUA and IHC) demonstrated AQUA analyses of tumors represented in TMAs provide reliable, quantitative measures of marker expression. We have also compared some commercially available imaging analysis software to pathologists measurement and our data suggested that automated analysis of IHC markers represents a promising approach for analyzing large numbers of breast cancer tissues in epidemiologic investigations.. We are also exploring the utility of the imaging analysis in scoring marker expression in 1,547 non-invasive tissue cores including normal TDLUs and DCIS constructed on 32 TMA blocks. In addition to TMA analyses of candidate markers in fixed tissues, we have conducted tumor profiling for gene expression and copy number changes in frozen tumors from a subset of Polish cases to better define molecular subtypes that are associated with distinct etiologic pathways. Renal cell carcinoma (RCC) rates in Central and Eastern Europe are among the highest in the world. The von Hippel Lindau-Hypoxia Inducible Factor (VHL-HIF) pathway has been implicated in kidney cancer tumorigenesis. We investigated the role of common variants in genes in the VHLHIF pathway in the susceptibility of sporadic RCC and clear cell RCC. We identified common genetic variants in genes in the VHL-HIF pathway associated with kidney cancer risk. Genotyping results for these variants are now available and are being examined for confirmation in several additional study populations. We are continuing to conduct studies based on Swedish linked registry data to better define the pattern of lymphoid malignancies that co-aggregate in families. We have conducted detailed analyses of the precursor condition, monoclonal gammopathy of uncertain significance (MGUS). We found that relatives of MGUS patients had a 3-fold increased risk of developing MGUS and 3-fold risk of developing multiple myeloma (MM). Risks for Waldenstrom macroglobulinemia and CLL were also increased. Some differences were seen by MGUS subtype. Relatives of patients with MM were at increased risk for MGUS or MM. The risk of any solid tumor was elevated among relatives of both MGUS and MM patients although the risk was small (HR=1.1, 95% CI=1.0-1.2). We have also refined our estimates of lymphoma aggregation by classifying lymphoma into subtypes sing the WHO classification. We found that relatives of patients with diffuse large b-cell lymphoma (DLBCL) had a 10-fold increased risk of developing DLBCL, a 2-fold elevated risk for Hodgkin lymphoma, but no increased risk for developing follicular lymphoma (FL). Similarly, relatives of patients with FL had a 4-fold increased risk for developing FL, a 2-fold increased risk for all indolent B-cell lymphomas but no increased risk for DLBCL.
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