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Under conditions of reduced tissue oxygenation, hypoxia-inducible factor (HIF) controls many processes, including angiogenesis and cellular metabolism, and also influences cell proliferation and survival decisions. HIF is centrally involved in tumour growth in inherited diseases that give rise to renal cell carcinoma (RCC), such as Von Hippel-Lindau syndrome and tuberous sclerosis complex. In this study, we examined whether HIF is involved in tumour formation of RCC in Birt-Hogg-Dubé syndrome. For this, we analysed a Birt-Hogg-Dubé patient-derived renal tumour cell line (UOK257) that is devoid of the Birt-Hogg-Dubé protein (BHD) and observed high levels of HIF activity. Knockdown of BHD expression also caused a threefold activation of HIF, which was not as a consequence of more HIF1α or HIF2α protein. Transcription of HIF target genes VEGF, BNIP3 and CCND1 was also increased. We found nuclear localization of HIF1α and increased expression of VEGF, BNIP3 and GLUT1 in a chromophobe carcinoma from a Birt-Hogg-Dubé patient. Our data also reveal that UOK257 cells have high lactate dehydrogenase, pyruvate kinase and 3-hydroxyacyl-CoA dehydrogenase activity. We observed increased expression of pyruvate dehydrogenase kinase 1 (a HIF gene target), which in turn leads to increased phosphorylation and inhibition of pyruvate dehydrogenase. Together with increased protein levels of GLUT1, our data reveal that UOK257 cells favour glycolytic rather than lipid metabolism (a cancer phenomenon termed the 'Warburg effect'). UOK257 cells also possessed a higher expression level of the L-lactate influx monocarboxylate transporter 1 and consequently utilized L-lactate as a metabolic fuel. As a result of their higher dependency on glycolysis, we were able to selectively inhibit the growth of these UOK257 cells by treatment with 2-deoxyglucose. This work suggests that targeting glycolytic metabolism may be used therapeutically to treat Birt-Hogg-Dubé-associated renal lesions. [ABSTRACT FROM AUTHOR]

Vos J, Oosterwijk JC, Gómez-García E, Menko FH, Jansen AM, Stoel RD, van Asperen CJ, Tibben A, Stiggelbout AM. Perceiving cancer-risks and heredity-likelihood in genetic-counseling: how counselees recall and interpret BRCA 1/2-test results. Previous studies on the counsellees' perception of DNA test results did not clarify whether counsellees were asked about their recollections or interpretations, and focused only on patients' own risks and not on the likelihood that cancer is heritable in the family. We tested differences and correlations of four perception aspects: recollections and interpretations of both cancer risks and heredity likelihood. In a retrospective study, women tested for BRCA1/2 on average, 5 years ago, completed questionnaires about their perception. Participants had received an unclassified variant ( n = 76), uninformative ( n = 76) or pathogenic mutation ( n = 51) result in BRCA1/2. Analyses included t-tests, correlations and structural equation modelling. The counsellees' perception showed to consist of four distinctive phenomena: recollections and interpretations of cancer risks and of heredity likelihood. This distinctiveness was suggested by significant differences between these perception variables. Moderate to strong correlations were found between these variables, suggesting that these differences between variables were consistent. The relationships between these variables were not influenced by actually communicated DNA test results, sociodemographics, medical and pedigree information, or framing of cancer risk questions. The largest differences between recollections and interpretations were found in the unclassified variant group and the smallest in uninformatives. Cancer risks and heredity likelihood correlated least in the pathogenic mutation group. Communication of ambiguous genetic information enlarged the differences. To understand the counsellees' perception of genetic counselling, researchers should study recollections and interpretations of cancer risks and heredity likelihood. Genetic counsellors should explicitly address the counsellees' recollections and interpretations, and be aware of possible inaccuracies. [ABSTRACT FROM AUTHOR]

Background: About 5% of all breast cancer cases are attributable to germline mutations in BRCA1 or BRCA2 genes. BRCA mutations in suspected carriers, however, may be missed, which hampers genetic counselling. Materials and methods: Different clinicopathological features were compared between 22 breast cancers from carriers of proved BRCA1 mutations and 604 cancers from sporadic controls. In addition, 5 BRCA2- related breast cancers and 66 breast cancers of untested patients at intermediate risk and 19 breast cancers of untested patients at high risk of hereditary disease on the basis of family history were evaluated. Results: A ‘probably sporadic’ class (age ⩾54 years and epidermal growth factor receptor (EGFR) negative; 68% of cases) with a 0% chance of BRCA1-related breast cancer containing 79% of the sporadic cases was yielded by using a decision tree with age, Ki67 and EGFR. A 75% chance of BRCA1-related breast cancer was shown by the ‘probably BRCA1-related’ class (age <54 years and Ki67 ⩾25%; 8% of cases) with 82% of the BRCA1-related cases but only 1 .4% of the sporadic cases. Most cases at intermediate or high risk of hereditary disease on the basis of family history could be classified with high probability as either probably BRCA1 related or probably sporadic. Conclusion: Breast carcinomas can be classified with a high level of certainty as sporadic or related to BRCA1 germline mutations by using a decision tree with age, Ki67 and EGFR. This can be clinically useful in mutation analysis in families with a borderline risk of hereditary disease. [ABSTRACT FROM AUTHOR]

Background: In BRCA2 mutation carriers, increased risks have been reported for several cancer sites besides breast and ovary. As most of the families included in earlier reports were selected on the basis of multiple breast/ovarian cancer cases, it is possible that risk estimates may differ in mutation carriers with a less striking family history. Methods: In the Netherlands, 139 BRCA2 families with 66 different pathogenic mutations were included in a nationwide study. To avoid testing bias, we chose not to estimate risk in typed carriers, but rather in male and female family members with a 50% prior probability of being a carrier (n=1811). The relative risk (RR) for each cancer site with the exception of breast and ovarian cancer was determined by comparing observed numbers with those expected, based on Dutch cancer incidence rates. Results: We observed an excess risk for four cancer sites: pancreas (RR 5.9; 95% confidence interval (CI) 3.2 to 10.0), prostate (2.5; 1.6 to 3.8), bone (14.4; 2.9 to 42.1) and pharynx (7.3; 2.0 to 18.6). A small increase was observed far cancer of the digestive tract (1.5; 1.1 to 1.9). Histological verification was available for 46% of the tumours. Nearly all increased risks reached statistical significance for men only. Cancer risks tended to be higher far people before the age of 65 years. Moreover, families with mutations outside the previously defined ovarian cancer cluster region tended to have a higher cancer risk. Conclusions: We found that BRCA2 carriers are at increased risk far cancers of the prostate and pancreas, and possibly bone and pharynx. Larger databases with extended fallow up are needed to provide insight into mutation specific risks of selected carriers in BRCA2 families. [ABSTRACT FROM AUTHOR]