Background: Women who are genetically predisposed to ovarian cancer are at very high risk of developing this disease. Although risk-reducing salpingo-oophorectomy (RRSO) and various screening regimens are currently recommended to reduce ovarian cancer risk, the optimal management strategy has not been established nor have multiple additional issues been adequately addressed. We developed a collaboration among the Clinical Genetics Branch (National Cancer Institute's Intramural Research Program), the Gynecologic Oncology Group (GOG), and the Cancer Genetics Network to address these issues. Methods: This is a prospective, international, twocohort, nonrandomized study of women at genetic risk of ovarian cancer, who chose either to undergo RRSO or screening, at study enrollment. Primary study objectives include quantifying and comparing ovarian and breast cancer incidence in the two study groups, assessing feasibility and selected performance characteristics of a novel ovarian cancer screening strategy (the Risk of Ovarian Cancer Algorithm), evaluating various aspects of quality of life and nononcologic morbidity related to various interventions in at-risk women, and creating a biospecimen repository for subsequent translational research.

The tyrosinase promoter has been used to target expression of the mutated human T24 Ha-ras oncogene in pigment-producing cells of transgenic mice. Two independent founder mice carrying the transgene survived and showed the same distinct phenotype of mutated coat color, deeply pigmented skin with multiple nevi, and twirling behavior. The offspring of one of these founders were developed into a line that stably expressed the same phenotype. Histopathological analysis of the tissues revealed hyperpigmentation and/or melanocytic hyperplasia in the skin, eyes, inner ear, and meningeal membranes in the brain. Reverse transcriptase-polymerase chain reaction analysis revealed expression of the transgene in skin, brain, and spleen. We propose that these transgenic mice will be a model for studying the process of multistage melanoma carcinogenesis and a system for evaluating potential chemopreventive agents.

Retinoids, the analogs of vitamin A, are active in vitro and in vivo against squamous cell carcinoma in animals and against certain epithelial precancers and cancers in humans. These data led us to design a prospective, multi-institutional, randomized phase II trial of isotretinoin in advanced head and neck squamous cell carcinoma. We randomly assigned 40 patients to receive isotretinoin or methotrexate, the best-studied and most active single agent for this disease. Overall, the study patients had extremely poor prognoses, i.e., low performance statuses and recurring disease after surgery and/or irradiation. Three objective responses (16%), including one complete response, occurred in the 19 evaluable isotretinoin-treated patients. Only one minor response (5%) occurred in the methotrexate-treated group. Toxicity occurred with both drugs, but was manageable and never life threatening in the retinoid group. These results and the established activity of retinoids in oral leukoplakia (a precursor of head and neck cancer) indicate the need for further study of this class of drugs in head and neck cancer.

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Papillary urothelial neoplasia of low malignant potential (PUNLMP) recurs in approximately 35% of patients. Conventional histopathological assessment does not distinguish non-recurrent from recurrent PUNLMP. The aim of the study was to explore the differences in global histone acetylation and global DNA methylation between non-recurrent and recurrent PUNLMP. Acetylated histone H3 lysine 9 (AcH3K9) and 5-methylcytosine (5MeC) were investigated by immunohistochemistry (IHC) in 20 PUNLMP cases (10 non-recurrent and 10 recurrent), in 5 cases of normal urothelium (NU) and in 5 cases of muscle invasive pT2 urothelial carcinoma (UC). The total optical density of the nuclear staining was measured photometrically in at least 40 nuclei separately for the basal, intermediate and luminal positions in each case. Concerning the total optical density values for both acetylation and methylation, a decrease in staining is observed from non-recurrent PUNLMP to recurrent PUNLMP, at all nuclear locations. For acetylation the mean value in non-recurrent. PUNLMP, intermediate between NU and UC, is closer to the former than to latter. The mean value in recurrent PUNLMP is closer to UC than to NU. In NU, non-recurrent and recurrent PUNLMP the acetylation to methylation ratio decreased from the nuclei in basal position to those in the surface, the average for the above groups being 1.491, 1.611 and 1.746, respectively. Setting the observed values for NU at each sampling location to unity, acetylation shows a steady decrease, the percentages of changes in this nuclear location compared to NU being − 5% in non-recurrent PUNLMP, − 15% in recurrent PUNLMP and − 24% in UC. Concerning methylation, there is slight increase in non-recurrent PUNLMP (+ 5%), a decrease in recurrent PUNLMP (− 19%) followed by a sharp rise for the UC (+ 61%). In conclusion there are differences in global histone acetylation and DNA methylation patterns between non-recurrent and recurrent PUNLMP. Further studies are needed to elucidate the complex interplay between chromatin structure, its modifications and recurrence of PUNLMP.