Beebe‐Dimmer, Jennifer

Abstract Background: A rare nonconservative substitution (G84E) in the HOXB13 gene has been shown to be associated with risk of prostate cancer. DNA samples from male patients included in the Mayo Clinic Biobank (MCB) were genotyped to determine the frequency of the G84E mutation and its association with various cancers. Methods: Subjects were genotyped using a custom TaqMan (Applied Biosystems) assay for G84E (rs138213197). In addition to donating a blood specimen, all MCB participants completed a baseline questionnaire to collect information on medical history and family history of cancer. Results: Forty-nine of 9,012 male patients were carriers of G84E (0.5%). Thirty-one percent (n = 2,595) of participants had been diagnosed with cancer, including 51.1% of G84E carriers compared with just 30.6% of noncarriers (P = 0.004). G84E was most frequently observed among men with prostate cancer compared with men without cancer (P < 0.0001). However, the mutation was also more commonly observed in men with bladder cancer (P = 0.06) and leukemia (P = 0.01). G84E carriers were more likely to have a positive family history of prostate cancer in a first-degree relative compared to noncarriers (36.2% vs. 16.0%, P = 0.0003). Conclusions: Our study confirms the association between the HOXB13 G84E variant and prostate cancer and suggests a novel association between G84E and leukemia and a suggestive association with bladder cancer. Future investigation is warranted to confirm these associations in order to improve our understanding of the role of germline HOXB13 mutations in human cancer. Impact: The associations between HOXB13 and prostate, leukemia, and bladder suggest that this gene is important in carcinogenesis. Cancer Epidemiol Biomarkers Prev; 24(9); 1366–72. ©2015 AACR.

Abstract Background: Statins are the most widely prescribed cholesterol-lowering drugs in the United States, with approximately 25% of US adults using statins by 2008. The anti-carcinogenic effect of statins may reduce the metastatic potential of cancer cells leading to ‘stage migration’ with statin users more likely diagnosed with early rather than late stage cancer. We evaluated the effects of statins on breast cancer stage migration and breast cancer-specific mortality in the Women’s Health Initiative (WHI) Clinical Trial and Observational Study. Methods: The study population included 128,675 postmenopausal women aged 50 to 79 years, with 7,883 newly-diagnosed pathologically-confirmed cases of in situ (19%), local stage (61%), regional stage (19%) and distant stage (1%) breast cancer and 401 deaths due to breast cancer after an average of 11.5 (SD=3.7) years of follow-up. To reduce the possibility of detection bias, we excluded women who did not report a mammogram within 5 years of study entry, and who had no health insurance or medical care provider (n=28,237). Stage was coded using criteria implemented in the Surveillance, Epidemiology and End Results Program and stratified into early stage (in situ and local) vs. late stage (regional and distant). Information on statin use prior to breast cancer diagnosis was collected at baseline and years one, three, six, and nine years post-baseline. Self- and interviewer-administered questionnaires were used to collect risk factor information. Cause of death was based on medical record review by physician adjudicators. Cox proportional hazards regression models were used to calculate hazard ratios (HR) with 95% confidence intervals (CI) to evaluate the relationship between statin use as a time-dependent exposure and diagnosis of late stage breast cancer and breast cancer-specific mortality adjusting for important confounders. For these models, participants who had early stage breast cancer or who died during follow-up were censored at time of diagnosis or death, respectively. We also evaluated the effect of statins stratified by estrogen receptor (ER) status. Statistical tests were two-sided. Results: Statins were used by 10,474 women (8%) at baseline. In the multivariable-adjusted time-dependent model, statin use was associated with a marginal reduction in risk of late stage breast cancer (HR 0.84, 95% CI: 0.70-1.02, p=0.082) and a reduction in risk of late stage estrogen receptor positive breast cancer (HR 0.79, 95% CI: 0.63-0.99, p=0.044). Statin use was also associated with a marginal reduction in breast cancer-specific mortality although it did not reach statistical significance (HR 0.59, 95% CI: 0.32-1.06, p=0.075). Conclusions: In the WHI, statin use was associated with a modest reduction in risk of late stage estrogen positive breast cancer and a non-significant decrease in breast cancer mortality. We are currently performing sensitivity analyses on these models. Studies using other large data sets with longer follow-up and information on cancer-directed therapy are needed to further evaluate this possible association. Citation Format: Monica P Arun, Pinkal Desai, Amy Lehman, Marilyn L Kwan, JoAnn E Manson, Sayeh Lavasani, Sylvia Wasswertheil-Smoller, Gloria E Sarto, Meryl S LeBoff, Jane Cauley, Michele L Cote, Jennifer Beebe-Dimmer, Allison Jay, Rowan T Chlebowski, Michael S Simon. Statins and breast cancer stage and mortality in the Women's Health Initiative cohort [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-10-04.

Abstract Germ line mutations in several genes (BRCA1, BRCA2, and CHEK2) whose products are involved in the DNA damage–signaling pathway have been implicated in prostate cancer risk. To identify additional genes in this pathway that might confer susceptibility to this cancer, we analyzed a recently identified DNA damage–response gene, p53AIP1 (a gene encoding for p53-regulated apoptosis-inducing protein 1), for genetic variants in prostate cancer. Five novel germ line variants were identified. The two truncating variants (Ser32Stop and Arg21insG) were found in 3% (4 of 132) of unselected prostate tumor samples. Genotyping of the two variants in an additional 393 men with sporadic prostate cancer showed a frequency of 3.1% (12 of 393) in contrast to 0.6% (2 of 327) in 327 unaffected men (Fisher's exact test, P = 0.018), with an odds ratio (OR) of 5.1 [95% confidence interval (95% CI), 1.1-23.0]. In addition, two of six tumors carrying the truncating variants were associated with loss of heterozygosity of the wild-type alleles, suggesting that p53AIP1 may act as a tumor suppressor. We also showed that the truncated p53AIP1 was unable to induce apoptosis and suppress cell growth in HeLa and COS-7 cells. These results suggest that loss-of-function variants in p53AIP1 associated with the risk of sporadic prostate cancer and further support the concept that the genetic defects in the DNA damage–response genes play an important role in the development of prostate cancer. (Cancer Res 2006; 66(21): 10302-7)