No Evidence That Genetic Variation in the Myeloid-Derived Suppressor Cell Pathway Influences Ovarian Cancer Survival.

Background: The precise mechanism by which the immune system is adversely affected in cancer patients remains poorly understood, but the accumulation of immunosuppressive/protumorigenic myeloid-derived suppressor cells (MDSCs) is thought to be a prominent mechanism contributing to immunologic tolerance of malignant cells in epithelial ovarian cancer (EOC). To this end, we hypothesized genetic variation in MDSC pathway genes would be associated with survival after EOC diagnoses.Methods: We measured the hazard of death due to EOC within 10 years of diagnosis, overall and by invasive subtype, attributable to SNPs in 24 genes relevant in the MDSC pathway in 10,751 women diagnosed with invasive EOC. Versatile Gene-based Association Study and the admixture likelihood method were used to test gene and pathway associations with survival.Results: We did not identify individual SNPs that were significantly associated with survival after correction for multiple testing (P < 3.5 × 10-5), nor did we identify significant associations between the MDSC pathway overall, or the 24 individual genes and EOC survival.Conclusions: In this well-powered analysis, we observed no evidence that inherited variations in MDSC-associated SNPs, individual genes, or the collective genetic pathway contributed to EOC survival outcomes.Impact: Common inherited variation in genes relevant to MDSCs was not associated with survival in women diagnosed with invasive EOC. Cancer Epidemiol Biomarkers Prev; 26(3); 420-4. ©2016 AACR.

Risk Analysis of Prostate Cancer in PRACTICAL, a Multinational Consortium, Using 25 Known Prostate Cancer Susceptibility Loci.

BACKGROUND: Genome-wide association studies have identified multiple genetic variants associated with prostate cancer risk which explain a substantial proportion of familial relative risk. These variants can be used to stratify individuals by their risk of prostate cancer. METHODS: We genotyped 25 prostate cancer susceptibility loci in 40,414 individuals and derived a polygenic risk score (PRS). We estimated empirical odds ratios (OR) for prostate cancer associated with different risk strata defined by PRS and derived age-specific absolute risks of developing prostate cancer by PRS stratum and family history. RESULTS: The prostate cancer risk for men in the top 1% of the PRS distribution was 30.6 (95% CI, 16.4-57.3) fold compared with men in the bottom 1%, and 4.2 (95% CI, 3.2-5.5) fold compared with the median risk. The absolute risk of prostate cancer by age of 85 years was 65.8% for a man with family history in the top 1% of the PRS distribution, compared with 3.7% for a man in the bottom 1%. The PRS was only weakly correlated with serum PSA level (correlation = 0.09). CONCLUSIONS: Risk profiling can identify men at substantially increased or reduced risk of prostate cancer. The effect size, measured by OR per unit PRS, was higher in men at younger ages and in men with family history of prostate cancer. Incorporating additional newly identified loci into a PRS should improve the predictive value of risk profiles. IMPACT: We demonstrate that the risk profiling based on SNPs can identify men at substantially increased or reduced risk that could have useful implications for targeted prevention and screening programs.

Evaluation of a new multiplex real-time polymerase chain reaction assay for the detection of human papillomavirus infections in a referral population.

OBJECTIVES: Human papillomavirus (HPV) testing is an important part of cervical cancer screening and management of women with atypical screening results. This study was conducted to evaluate the analytical and clinical performance of the Abbott RealTime High-Risk HPV assay (RealTime) in a referral population, in comparison to the Qiagen Hybrid Capture 2 High-Risk HPV DNA Test (hc2). METHODS: RealTime is a new polymerase chain reaction assay that detects 14 high-risk HPV genotypes with simultaneous differentiation between HPV 16 and HPV 18. Five hundred forty-five routine cervical smear samples (ThinPrep) from women who were referred to 2 German colposcopy clinics were included in the study. All samples were tested with both assays for the detection of high-risk HPV DNA. Specimens with repeatedly discordant results were genotyped by Linear Array (Roche) and in-house polymerase chain reaction assays. RESULTS: Both assays showed excellent overall agreement (92.8%; κ = 0.86) on 545 samples. Analytical sensitivity of RealTime was comparable to that of hc2 (97.6% vs 95.1%, P = 0.189), whereas RealTime demonstrated significantly higher analytical specificity compared with hc2 (100% vs 93.1%, P < 0.0001). RealTime showed no cross-reactivity with untargeted HPV genotypes in this study. The clinical performance of the assays was evaluated based on histology results available from 319 women (90 nonpathological, 73 cervical intraepithelial neoplasia [CIN] 1, 75 CIN 2, 74 CIN 3, and 7 invasive cancers). High-risk HPV detection rates observed in women with CIN 1, CIN 2+, and CIN 3+ diagnosis, respectively, were comparable for both assays: 47.9%, 92.3%, and 97.5% (RealTime) and 47.9%, 92.3%, and 93.8% (hc2). Detection of HPV 16/18 with RealTime was highly correlated with severity of dysplasia: less than CIN 2, 30.5%; CIN 2+, 59.0%; CIN 3+, 71.6%. CONCLUSIONS: These results support the use of RealTime for routine detection of HPV infections in a referral population.

Genetic determination of chromosomal radiosensitivities in G0- and G2-phase human lymphocytes.

BACKGROUND AND PURPOSE: The radiosensitivity of human lymphocytes measured using a G0- or G2-assay has been linked with an individual's risk of developing normal tissue complications following radiotherapy. This study was performed to increase basic knowledge of the genetics of the human radiation response, and chromosomal aberration induction in particular. MATERIALS AND METHODS: The study was carried out with blood samples taken from 15 monozygotic twin pairs. G0-assay was performed for cells irradiated with 6 Gy counting only deletions and G2-assay for cells irradiated with 0.5 Gy scoring only chromatid breaks. RESULTS: The mean number of deletions measured at 6 Gy for all 30 samples using the G0-assay amounted to 2.96+/-0.37 (means+/-SD), which corresponds to a coefficient of variation (CV) of 13%. There is a highly significant intra-pair correlation for this number among twins (r(2)=0.911) demonstrating that this parameter is mostly determined by genetic factors. According to the mean number of deletions, a theoretical classification based on the definition < or = MV-SD as resistant, MV+/-SD as normal and > or = MV+SD as sensitive was made, identifying two pairs as sensitive or resistant, respectively, while nine were normal and two pairs are intermediate. For chromatid breaks measured at 0.5 Gy with the G2-assay the mean number was 1.35+/-0.42 (means+/-SD) corresponding to a CV of 31%. There was again a strong intra-pair correlation among twins with r(2)=0.837 showing that this sensitivity is also determined mostly by genetic factors. There was, however, no inter-assay correlation between the G0- and G2-sensitivity (r(2)=0.006) demonstrating that these two sensitivities depend on different genetic factors. CONCLUSION: The chromosomal radiosensitivity of lymphocytes as defined by G0- or G2-assay is largely determined by different genetic factors, which may allow the use of genetic profiling as an indicator of the respective individual radiosensitivity.