Opportunities and challenges in ovarian cancer research, a perspective from the 11th Ovarian cancer action/HHMT Forum, Lake Como, March 2007.

Advances in surgery and chemotherapy have improved the 5-year survival for patients with epithelial ovarian cancer, but have not impacted on the ultimate rate of cure in a disease that is diagnosed in late stage and that recurs in the majority of patients. "Omic" technologies promise to define genetically driven aberrant signaling pathways in malignant cells, provided that bioinformatic expertise can be focused on a cancer that is neither common nor rare. Molecular therapeutics must be linked to molecular diagnostics to permit individualized therapy. Not only epithelial cancer cells but also stroma, vasculature and the immune response must be targeted. Closer collaboration between academic institutions, biotech and pharma will be required to facilitate this process and to interest the private sector in an orphan disease. New preclinical models may permit more efficient development of drugs and siRNA that can target dormant drug resistant stem cells. Strategies must be developed to deal with the heterogeneity of different grades and histotypes. Identification of women at increased risk will facilitate prevention and early detection in subsets of patients. BRCA1/2 might be sequenced in all ovarian cancer patients to identify new kindreds. Epidemiologic algorithms are being developed and validated. Awareness must be raised that oral contraceptives can reduce risk of developing ovarian cancer by 50%. Early detection is likely to require panels of complementary biomarkers, analyzed by sophisticated statistical techniques, to improve sensitivity while maintaining extremely high specificity. As ovarian cancer becomes a chronic disease, greater emphasis will be placed on the challenges facing survivors.

MSH6 germline mutations are rare in colorectal cancer families.

Germline mutations in MSH6 can cause HNPCC, which is associated with a tumor phenotype featuring MSI. However, tumors arising in persons with disease-causing mutations of MSH6 may or may not exhibit MSI. We used D-HPLC to screen for germline mutations in the promoter region, the coding region and the 3'-UTR of MSH6. Eighty-four families, enrolled on the basis of Amsterdam I and II criteria (HNPCC families) and less stringent criteria (HNPCC-like families), were tested for MMR gene mutations; 27 families had a disease-causing mutation in MLH1 or MSH2, and the remaining 57 families were tested for mutations in MSH6. Two protein-truncating mutations were identified in each of 2 families fulfilling the Amsterdam I criteria, being present in persons affected with early-onset colorectal cancers exhibiting MSI. Immunohistochemical analysis showed that expression of both MSH2 and MSH6 proteins was lost in the cancer cells of the 2 mutation carriers but only MSH6 protein expression was lost in 2 adenomatous polyps. A third possibly disease-causing mutation was found in a person affected with a tumor that did not exhibit MSI. In addition, we found 4 new polymorphisms and determined that neither of the 2 studied by association analysis conferred susceptibility to colorectal or endometrial cancer. Altogether, our results indicate that disease-causing germline mutations of MSH6 are rare in HNPCC and HNPCC-like families.