Genetic risk impacts the association of menopausal hormone therapy with colorectal cancer risk.

BACKGROUND: Menopausal hormone therapy (MHT), a common treatment to relieve symptoms of menopause, is associated with a lower risk of colorectal cancer (CRC). To inform CRC risk prediction and MHT risk-benefit assessment, we aimed to evaluate the joint association of a polygenic risk score (PRS) for CRC and MHT on CRC risk. METHODS: We used data from 28,486 postmenopausal women (11,519 cases and 16,967 controls) of European descent. A PRS based on 141 CRC-associated genetic variants was modeled as a categorical variable in quartiles. Multiplicative interaction between PRS and MHT use was evaluated using logistic regression. Additive interaction was measured using the relative excess risk due to interaction (RERI). 30-year cumulative risks of CRC for 50-year-old women according to MHT use and PRS were calculated. RESULTS: The reduction in odds ratios by MHT use was larger in women within the highest quartile of PRS compared to that in women within the lowest quartile of PRS (p-value = 2.7 × 10-8). At the highest quartile of PRS, the 30-year CRC risk was statistically significantly lower for women taking any MHT than for women not taking any MHT, 3.7% (3.3%-4.0%) vs 6.1% (5.7%-6.5%) (difference 2.4%, P-value = 1.83 × 10-14); these differences were also statistically significant but smaller in magnitude in the lowest PRS quartile, 1.6% (1.4%-1.8%) vs 2.2% (1.9%-2.4%) (difference 0.6%, P-value = 1.01 × 10-3), indicating 4 times greater reduction in absolute risk associated with any MHT use in the highest compared to the lowest quartile of genetic CRC risk. CONCLUSIONS: MHT use has a greater impact on the reduction of CRC risk for women at higher genetic risk. These findings have implications for the development of risk prediction models for CRC and potentially for the consideration of genetic information in the risk-benefit assessment of MHT use.

Health insurance coverage and poverty status of postpartum women in the United States in 2019: an ACS-PUMS population-based cross-sectional study.

BACKGROUND: A quarter of United States (US) postpartum women still report unmet health care needs and health care unaffordability. We aimed to study associations between receipt of health insurance coverage and poverty status/receipt of government financial support and determine coverage gaps overall and by social factors among US postpartum women in poverty. METHODS: This study design is a cross-sectional study using secondary data. We included women who gave birth within the last 12 months from 2019 American Community Survey Public Use Microdata Sample. Poverty was defined as having an income-to-poverty ratio of less than 100%. We explored Medicaid/government medical assistance gaps among women in poverty. To examine the associations between Medicaid/government medical assistance (exposures) and poverty/government financial support (outcomes), we used age-, race-, and multivariable-adjusted logistic regression models. We also evaluated the associations of state, race, citizenship status, or language other than English spoken at home (exposures) with receipt of Medicaid/government medical assistance (outcomes) among women in poverty through multivariable-adjusted logistic regression. RESULTS: It was notable that 35.6% of US postpartum women in poverty did not have Medicaid/government medical assistance and only a small proportion received public assistance income (9.8%)/supplementary security income (3.1%). Women with Medicaid/government medical assistance, compared with those without the coverage, had statistically significantly higher odds of poverty [adjusted odds ratio (aOR): 3.15, 95% confidence interval (95% CI): 2.85-3.48], having public assistance income (aOR: 24.52 [95% CI: 17.31-34.73]), or having supplementary security income (aOR: 4.22 [95% CI: 2.81-6.36]). Also, among postpartum women in poverty, women in states that had not expanded Medicaid, those of Asian or other race, non-US citizens, and those speaking another language had statistically significantly higher odds of not receiving Medicaid/government medical assistance [aORs (95% CIs): 2.93 (2.55-3.37); 1.30 (1.04-1.63); 3.65 (3.05-4.38); and 2.08 (1.86-2.32), respectively]. CONCLUSIONS: Our results showed that the receipt of Medicaid/government medical assistance is significantly associated with poverty and having government financial support. However, postpartum women in poverty still had Medicaid/government medical assistance gaps, especially those who lived in states that had not expanded Medicaid, those of Asian or other races, non-US citizens, and other language speakers.

Coffee, Citrus, and Alcohol: A Review of What We Drink and How it May Affect our Risk for Skin Cancer.

Climate change and environmental health are closely linked with agriculture and food supply. The environment influences accessibility, quality, and variety of foods and drinks that are available for consumption, which in turn influences population health. A growing area of research is the role of dietary intake of nutrients and how they may influence risk for skin cancer. In recent years, our group has studied dietary nutrients, particularly those found in commonly consumed beverages, such as those containing caffeine, citrus products, and alcohol, in large prospective cohorts to evaluate how their intake may influence risk for skin cancer. Our data suggest that intake of citrus juices, when consumed around once per day or more, or around 5 to 6 times per week, may be associated with increased risk for both keratinocyte carcinomas (KC) and malignant melanoma (MM). With regards to alcohol consumption, we have found that intake of white wine may be associated with increased risk for both KC and MM, while beer and red wine have not shown such associations. Lastly, our work suggests caffeinated beverages, including coffee, tea, and cola, may be associated with decreased risk for basal cell carcinoma (BCC) and MM. While the associations between food intake and skin cancer development are complex, and remain to be further analyzed in future studies, we hope that our summary may help guide individuals to small changes they may make towards potentially reducing their risk for certain skin cancers.

Cumulative Erythemal Ultraviolet Radiation and Risk of Cancer in 3 Large US Prospective Cohorts.

Ultraviolet radiation (UVR) exposure is the major risk factor for melanoma. However, epidemiologic studies on UVR and noncutaneous cancers have reported inconsistent results, with some suggesting an inverse relationship potentially mediated by vitamin D. To address this, we examined 3 US prospective cohorts, the Health Professionals Follow-up Study (HPFS) (1986) and Nurses' Health Study (NHS) I and II (1976 and 1989), for associations between cumulative erythemal UVR and incident cancer risk, excluding nonmelanoma skin cancer. We used a validated spatiotemporal model to calculate erythemal UVR. Participants (47,714 men; 212,449 women) were stratified into quintiles by cumulative average erythemal UVR, using the first quintile as referent, for Cox proportional hazards regression analysis. In the multivariable-adjusted meta-analysis of all cohorts, compared with the lowest quintile, risk of any cancer was slightly increased across all other quintiles (highest quintile hazard ratio (HR) = 1.04, 95% confidence interval (CI): 1.01, 1.07; P for heterogeneity = 0.41). All UVR quintiles were associated with similarly increased risk of any cancer excluding melanoma. As expected, erythemal UVR was positively associated with risk of melanoma (highest quintile HR = 1.17, 95% CI: 1.04, 1.31; P for heterogeneity = 0.83). These findings suggest that elevated UVR is associated with increased risk of both melanoma and noncutaneous cancers.

Genetic variants of SDCCAG8 and MAGI2 in mitosis-related pathway genes are independent predictors of cutaneous melanoma-specific survival.

Mitosis is a prognostic factor for cutaneous melanoma (CM), but accurate mitosis detection in CM tissues is difficult. Therefore, the 8th Edition of the American Joint Committee on Cancer staging system has removed the mitotic rate as a category criterion of the tumor T-category, based on the evidence that the mitotic rate was not an independent prognostic factor for melanoma survival. As single-nucleotide polymorphisms (SNPs) have been shown to be potential predictors for cutaneous melanoma-specific survival (CMSS), we investigated the potential prognostic value of SNPs in mitosis-related pathway genes in CMSS by analyzing their associations with outcomes of 850 CM patients from The University of Texas MD Anderson Cancer Center in a discovery dataset and validated the findings in another dataset of 409 CM patients from the Harvard University Nurses' Health Study and Health Professionals Follow-up Study. In both datasets, we identified two SNPs (SDCCAG8 rs10803138 G>A and MAGI2 rs3807694 C>T) as independent prognostic factors for CMSS, with adjusted allelic hazards ratios of 1.49 (95% confidence interval = 1.17-1.90, P = .001) and 1.45 (1.13-1.86, P = .003), respectively. Furthermore, their combined unfavorable alleles also predicted a poor survival in both discovery and validation datasets in a dose-response manner (Ptrend  = .0006 and .0001, respectively). Additional functional analysis revealed that both SDCCAG8 rs10803138 A and MAGI2 rs3807694 T alleles were associated with elevated mRNA expression levels in normal tissues. Therefore, these findings suggest that SDCCAG8 rs10803138 G>A and MAGI2 rs3807694 C>T are independent prognostic biomarkers for CMSS, possibly by regulating the mRNA expression of the corresponding genes involved in mitosis.

Comprehensive analysis of prognostic immune-related genes in the tumor microenvironment of cutaneous melanoma.

Cutaneous malignant melanoma (hereafter called melanoma) is one of the most aggressive cancers with increasing incidence and mortality rates worldwide. In this study, we performed a systematic investigation of the tumor microenvironmental and genetic factors associated with melanoma to identify prognostic biomarkers for melanoma. We calculated the immune and stromal scores of melanoma patients from the Cancer Genome Atlas (TCGA) using the ESTIMATE algorithm and found that they were closely associated with patients' prognosis. Then the differentially expressed genes were obtained based on the immune and stromal scores, and prognostic immune-related genes further identified. Functional analysis and the protein-protein interaction network further revealed that these genes enriched in many immune-related biological processes. In addition, the abundance of six infiltrating immune cells was analyzed using prognostic immune-related genes by TIMER algorithm. The unsupervised clustering analysis using immune-cell proportions revealed eight clusters with distinct survival patterns, suggesting that dendritic cells were most abundant in the microenvironment and CD8+ T cells and neutrophils were significantly related to patients' prognosis. Finally, we validated these genes in three independent cohorts from the Gene Expression Omnibus database. In conclusion, this study comprehensively analyzed the tumor microenvironment and identified prognostic immune-related biomarkers for melanoma.

DNA repair and cancer in colon and rectum: Novel players in genetic susceptibility.

Interindividual differences in DNA repair systems may play a role in modulating the individual risk of developing colorectal cancer. To better ascertain the role of DNA repair gene polymorphisms on colon and rectal cancer risk individually, we evaluated 15,419 single nucleotide polymorphisms (SNPs) within 185 DNA repair genes using GWAS data from the Colon Cancer Family Registry (CCFR) and the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), which included 8,178 colon cancer, 2,936 rectum cancer cases and 14,659 controls. Rs1800734 (in MLH1 gene) was associated with colon cancer risk (p-value = 3.5 × 10-6 ) and rs2189517 (in RAD51B) with rectal cancer risk (p-value = 5.7 × 10-6 ). The results had statistical significance close to the Bonferroni corrected p-value of 5.8 × 10-6 . Ninety-four SNPs were significantly associated with colorectal cancer risk after Binomial Sequential Goodness of Fit (BSGoF) procedure and confirmed the relevance of DNA mismatch repair (MMR) and homologous recombination pathways for colon and rectum cancer, respectively. Defects in MMR genes are known to be crucial for familial form of colorectal cancer but our findings suggest that specific genetic variations in MLH1 are important also in the individual predisposition to sporadic colon cancer. Other SNPs associated with the risk of colon cancer (e.g., rs16906252 in MGMT) were found to affect mRNA expression levels in colon transverse and therefore working as possible cis-eQTL suggesting possible mechanisms of carcinogenesis.

Meta-analysis of 16 studies of the association of alcohol with colorectal cancer.

Alcohol consumption is an established risk factor for colorectal cancer (CRC). However, while studies have consistently reported elevated risk of CRC among heavy drinkers, associations at moderate levels of alcohol consumption are less clear. We conducted a combined analysis of 16 studies of CRC to examine the shape of the alcohol-CRC association, investigate potential effect modifiers of the association, and examine differential effects of alcohol consumption by cancer anatomic site and stage. We collected information on alcohol consumption for 14,276 CRC cases and 15,802 controls from 5 case-control and 11 nested case-control studies of CRC. We compared adjusted logistic regression models with linear and restricted cubic splines to select a model that best fit the association between alcohol consumption and CRC. Study-specific results were pooled using fixed-effects meta-analysis. Compared to non-/occasional drinking (≤1 g/day), light/moderate drinking (up to 2 drinks/day) was associated with a decreased risk of CRC (odds ratio [OR]: 0.92, 95% confidence interval [CI]: 0.88-0.98, p = 0.005), heavy drinking (2-3 drinks/day) was not significantly associated with CRC risk (OR: 1.11, 95% CI: 0.99-1.24, p = 0.08) and very heavy drinking (more than 3 drinks/day) was associated with a significant increased risk (OR: 1.25, 95% CI: 1.11-1.40, p < 0.001). We observed no evidence of interactions with lifestyle risk factors or of differences by cancer site or stage. These results provide further evidence that there is a J-shaped association between alcohol consumption and CRC risk. This overall pattern was not significantly modified by other CRC risk factors and there was no effect heterogeneity by tumor site or stage.

Genetic variants in PDSS1 and SLC16A6 of the ketone body metabolic pathway predict cutaneous melanoma-specific survival.

A few single-nucleotide polymorphisms (SNPs) have been identified to be associated with cutaneous melanoma (CM) survival through genome-wide association studies, but stringent multiple testing corrections required for the hypothesis-free testing may have masked some true associations. Using a hypothesis-driven analysis approach, we sought to evaluate associations between SNPs in ketone body metabolic pathway genes and CM survival. We comprehensively assessed associations between 4196 (538 genotyped and 3658 imputed) common SNPs in 44 ketone body metabolic pathway genes and CM survival, using a dataset of 858 patients of a case-control study from The University of Texas M.D. Anderson Cancer Center as the discovery set and another dataset of 409 patients from the Nurses' Health Study and the Health Professionals Follow-up Study as the replication set. There were 95/858 (11.1%) and 48/409 (11.7%) patients who died of CM, respectively. We identified two independent SNPs (ie, PDSS1 rs12254548 G>C and SLC16A6 rs71387392 G>A) that were associated with CM survival, with allelic hazards ratios of 0.58 (95% confidence interval [CI] = 0.44-0.76, P = 9.00 × 10-5 ) and 1.98 (95% CI = 1.34-2.94, P = 6.30 × 10-4 ), respectively. Additionally, associations between genotypes of the SNPs and messenger RNA expression levels of their corresponding genes support the biologic plausibility of a role for these two variants in CM tumor progression and survival. Once validated by other larger studies, PDSS1 rs12254548 and SLC16A6 rs71387392 may be valuable biomarkers for CM survival.

Insulinemic Potential of Lifestyle Is Inversely Associated with Leukocyte Mitochondrial DNA Copy Number in US White Adults.

BACKGROUND: Poor lifestyles have been linked to insulin insensitivity/hyperinsulinemia, which may contribute to downstream changes such as inflammation and oxidative damage and the development of chronic diseases. As a biomarker of intracellular oxidative stress, leukocyte mitochondrial DNA copy number (mtDNA-CN) has been related to lifestyle factors including diet and weight. No epidemiologic study has examined the relation between combined insulinemic potential of lifestyle and mtDNA-CN. OBJECTIVES: Our aim was to examine the association between Empirical Lifestyle Index for Hyperinsulinemia (ELIH) and leukocyte mtDNA-CN in US men and women. METHODS: This cross-sectional analysis included 2835 white adults without cancers, diabetes, or cardiovascular disease at blood collection, including 2160 women from the Nurses' Health Study and 675 men from the Health Professionals Follow-Up Study. ELIH is an index based on plasma C-peptide that characterizes the insulinemic potential of lifestyle (diet, body weight, and physical activity). Relative mtDNA-CN in peripheral blood leukocytes was measured by qPCR-based assay. RESULTS: We found a significant inverse association between ELIH and mtDNA-CN. In multivariable-adjusted linear models, absolute least squares means ± SDs of mtDNA-CN z score across ELIH quintiles in women were as follows: Q1: 0.14 ± 0.05; Q2: 0.04 ± 0.06; Q3: 0.008 ± 0.05; Q4: 0.01 ± 0.05; and Q5: -0.06 ± 0.05 (P-trend = 0.006). Means ± SDs in men were as follows: Q1: 0.25 ± 0.09; Q2: 0.23 ± 0.09; Q3: 0.07 ± 0.09; Q4: 0.02 ± 0.09; and Q5: -0.04 ± 0.09 (P-trend = 0.007). Means ± SDs in all participants were as follows: Q1: 0.16 ± 0.05; Q2: 0.07 ± 0.05; Q3: 0.01 ± 0.05; Q4: 0.01 ± 0.05; and Q5: -0.05 ± 0.05 (P-trend = 0.0004). CONCLUSIONS: Hyperinsulinemic lifestyles (i.e., higher ELIH) were associated with lower leukocyte mtDNA-CN among subjects without major diseases, suggesting that the difference in lifestyle insulinemic potential may be related to excessive oxidative stress damage.

Intake of Furocoumarins and Risk of Skin Cancer in 2 Prospective US Cohort Studies.

BACKGROUND: In prior studies, higher citrus consumption was associated with higher risk of cutaneous malignant melanoma, squamous cell carcinoma (SCC), and basal cell carcinoma (BCC). Furocoumarins, compounds with phototoxicity and photocarcinogenicity in citrus, may be responsible for the association. OBJECTIVES: The objective of the study was to investigate the association between furocoumarin intake and skin cancer risk. METHODS: A total of 47,453 men from the Health Professionals Follow-Up Study (HPFS) and 75,291 women from the Nurses' Health Study (NHS) with diet data collected every 2-4 y in the 2 prospective cohort studies were included. A furocoumarin food composition database for 7 common furocoumarins [bergaptol, psoralen, 8-methoxypsoralen, bergapten, 6',7'-dihydroxybergamottin (6'7'-DHB), epoxybergamottin, and bergamottin] was developed and used to calculate participants' cumulative average and energy-adjusted furocoumarin intake. Multivariate HRs and 95% CIs of the associations between furocoumarin intake and skin cancer risk were estimated using Cox proportional hazards models. Analyses were performed separately in each cohort as well as pooled using a fixed-effects model. RESULTS: Throughout follow-up (1984-2012 in the NHS and 1986-2012 in the HPFS), we identified 1593 melanoma, 4066 SCC, and 28,630 BCC cases. Higher intake of total furocoumarins was associated with an increased risk of BCC; the pooled HR comparing the top with the bottom quintile was 1.16 (95% CI: 1.11, 1.21; P-trend = 0.002). Higher intakes of bergaptol, bergapten, 6'7'-DHB, and bergamottin were also significantly associated with increased BCC risk. No significant associations were found between intake of total furocoumarins and the risks of SCC or melanoma. CONCLUSIONS: Intakes of total furocoumarins as well as some individual furocoumarins were associated with an increased risk of skin cancer, especially BCC, in 2 cohorts of US health professionals.

Citrus Consumption and Risk of Cutaneous Malignant Melanoma in the Women's Health Initiative.

Citrus products are rich sources of furocoumarins, a class of photoactive compounds. Certain furocoumarins combined with ultraviolet radiation can induce skin cancer. We examined the relationship between citrus consumption and cutaneous melanoma risk among 56,205 Caucasian postmenopausal women in the Women's Health Initiative. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of melanoma by citrus intake level. During a mean follow-up of 15.7 years, 956 incident melanoma cases were documented. In multivariable adjusted models, the HR (95% CI) for melanoma was 1.12 (0.91, 1.37) among the highest citrus consumers (1.5+ servings/day of fruit or juice) versus the lowest (<2 servings/week), 0.95 (0.76, 1.20) among the highest citrus fruit consumers (5+ servings/week) versus non-consumers, and was 1.13 (0.96, 1.32) for the highest citrus juice consumers (1+ servings/day) versus the lowest (<1 serving/week). In stratified analyses, an increased melanoma risk associated with citrus juice intake was observed among women who spent the most time outdoors in summer as adults; the HR for the highest versus lowest intake was 1.22 (1.02, 1.46) (p trend = 0.03). Further research is needed to explore the association of melanoma with citrus juices among women with high sun exposure.

Height, nevus count, and risk of cutaneous malignant melanoma: Results from 2 large cohorts of US women.

BACKGROUND: Taller individuals are at higher risk of melanoma. OBJECTIVE: To prospectively investigate the association of height with nevus count and melanoma and estimate the proportion of height-melanoma association explained by nevus count among white participants from the Nurses' Health Study (NHS) and Nurses' Health Study 2 (NHS2). METHODS: We used Cox proportional hazards regression and multinomial logistic regression for data analyses, with adjustment of potential confounders in the multivariate model. RESULTS: We included 82,468 and 106,069 women from NHS and NHS2, respectively. The hazard ratio was 1.21 (95% confidence interval [CI] 1.12-1.31) for the association between every 10-cm increase in height and melanoma. Compared with women with no nevi, the odds ratios (95% CIs) associated with a 10-cm increase in height were 1.35 (95% CI 1.23-1.48) in the NHS and 1.12 (95% CI 1.09-1.15) in the NHS2 for women with greater than or equal to 10 moles. The proportion of excess melanoma risk associated with each 10-cm increase in height explained by nevus count was 8.03% in the NHS and 10.22% in the NHS2. LIMITATION: Self-reported height and nevus count. Mole counts were limited to 1 arm or both legs. CONCLUSION: Nevus count is an important explanatory factor for the excess risk of melanoma among taller white women.

Deep Metabolomics of a High-Grade Serous Ovarian Cancer Triple-Knockout Mouse Model.

High-grade serous carcinoma (HGSC) is the most common and deadliest ovarian cancer (OC) type, accounting for 70-80% of OC deaths. This high mortality is largely due to late diagnosis. Early detection is thus crucial to reduce mortality, yet the tumor pathogenesis of HGSC remains poorly understood, making early detection exceedingly difficult. Faithfully and reliably representing the clinical nature of human HGSC, a recently developed triple-knockout (TKO) mouse model offers a unique opportunity to examine the entire disease spectrum of HGSC. Metabolic alterations were investigated by applying ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) to serum samples collected from these mice at premalignant, early, and advanced stages of HGSC. This comprehensive analysis revealed a panel of 29 serum metabolites that distinguished mice with HGSC from controls and mice with uterine tumors with over 95% accuracy. Meanwhile, our panel could further distinguish early-stage HGSC from controls with 100% accuracy and from advanced-stage HGSC with over 90% accuracy. Important identified metabolites included phospholipids, sphingomyelins, sterols, N-acyltaurine, oligopeptides, bilirubin, 2(3)-hydroxysebacic acids, uridine, N-acetylneuraminic acid, and pyrazine derivatives. Overall, our study provides insights into dysregulated metabolism associated with HGSC development and progression, and serves as a useful guide toward early detection.

Genetic variants in the calcium signaling pathway genes are associated with cutaneous melanoma-specific survival.

Remodeling or deregulation of the calcium signaling pathway is a relevant hallmark of cancer including cutaneous melanoma (CM). In this study, using data from a published genome-wide association study (GWAS) from The University of Texas M.D. Anderson Cancer Center, we assessed the role of 41,377 common single-nucleotide polymorphisms (SNPs) of 167 calcium signaling pathway genes in CM survival. We used another GWAS from Harvard University as the validation dataset. In the single-locus analysis, 1830 SNPs were found to be significantly associated with CM-specific survival (CMSS; P ≤ 0.050 and false-positive report probability ≤ 0.2), of which 9 SNPs were validated in the Harvard study (P ≤ 0.050). Among these, three independent SNPs (i.e. PDE1A rs6750552 T>C, ITPR1 rs6785564 A>G and RYR3 rs2596191 C>A) had a predictive role in CMSS, with a meta-analysis-derived hazards ratio of 1.52 (95% confidence interval = 1.19-1.94, P = 7.21 × 10-4), 0.49 (0.33-0.73, 3.94 × 10-4) and 0.67 (0.53-0.86, 0.0017), respectively. Patients with an increasing number of protective genotypes had remarkably improved CMSS. Additional expression quantitative trait loci analysis showed that these genotypes were also significantly associated with mRNA expression levels of the genes. Taken together, these results may help us to identify prospective biomarkers in the calcium signaling pathway for CM prognosis.

Pre-diagnostic leukocyte mitochondrial DNA copy number and colorectal cancer risk.

Mitochondrial DNA (mtDNA) is susceptible to oxidative stress and mutation. Few epidemiological studies have assessed the relationship between mtDNA copy number (mtDNAcn) and risk of colorectal cancer (CRC), with inconsistent findings. In this study, we examined the association between pre-diagnostic leukocyte mtDNAcn and CRC risk in a case-control study of 324 female cases and 658 matched controls nested within the Nurses' Health Study (NHS). Relative mtDNAcn in peripheral blood leukocytes was measured by quantitative polymerase chain reaction-based assay. Conditional logistic regression models were applied to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the association of interest. Results showed lower log-mtDNAcn was significantly associated with increased risk of CRC, in a dose-dependent relationship (P for trend < 0.0001). Compared to the fourth quartile, multivariable-adjusted OR [95% confidence interval (CI)] was 1.10 (0.69, 1.76) for the third quartile, 1.40 (0.89, 2.19) for the second quartile and 2.19 (1.43, 3.35) for the first quartile. In analysis by anatomic subsite of CRC, we found a significant inverse association for proximal colon cancer [lowest versus highest quartile, multivariable-adjusted OR (95% CI) = 3.31 (1.70, 6.45), P for trend = 0.0003]. Additionally, stratified analysis according to the follow-up time since blood collection showed that the inverse association between mtDNAcn and CRC remained significant among individuals with ≥ 5 years' follow-up, and marginally significant among those with ≥ 10 years' follow-up since mtDNAcn testing, suggesting that mtDNAcn may serve as a long-term predictor for risk of CRC. In conclusion, pre-diagnostic leukocyte mtDNAcn was inversely associated with CRC risk. Further basic experimental studies are needed to explore the underlying biological mechanisms linking mtDNAcn to CRC carcinogenesis.

Genetic variants in ELOVL2 and HSD17B12 predict melanoma-specific survival.

Fatty acids play a key role in cellular bioenergetics, membrane biosynthesis and intracellular signaling processes and thus may be involved in cancer development and progression. In the present study, we comprehensively assessed associations of 14,522 common single-nucleotide polymorphisms (SNPs) in 149 genes of the fatty-acid synthesis pathway with cutaneous melanoma disease-specific survival (CMSS). The dataset of 858 cutaneous melanoma (CM) patients from a published genome-wide association study (GWAS) by The University of Texas M.D. Anderson Cancer Center was used as the discovery dataset, and the identified significant SNPs were validated by a dataset of 409 CM patients from another GWAS from the Nurses' Health and Health Professionals Follow-up Studies. We found 40 noteworthy SNPs to be associated with CMSS in both discovery and validation datasets after multiple comparison correction by the false positive report probability method, because more than 85% of the SNPs were imputed. By performing functional prediction, linkage disequilibrium analysis, and stepwise Cox regression selection, we identified two independent SNPs of ELOVL2 rs3734398 T>C and HSD17B12 rs11037684 A>G that predicted CMSS, with an allelic hazards ratio of 0.66 (95% confidence interval = 0.51-0.84 and p = 8.34 × 10-4 ) and 2.29 (1.55-3.39 and p = 3.61 × 10-5 ), respectively. Finally, the ELOVL2 rs3734398 variant CC genotype was found to be associated with a significantly increased mRNA expression level. These SNPs may be potential markers for CM prognosis, if validated by additional larger and mechanistic studies.

Genetic variants in glutamine metabolic pathway genes predict cutaneous melanoma-specific survival.

Glutamine dependence is a unique metabolic defect seen in cutaneous melanoma (CM), directly influencing the treatment and prognosis. Here, we investigated the associations between 6025 common single-nucleotide polymorphisms (SNPs) in 77 glutamine metabolic pathway genes with CM-specific survival (CMSS) using genotyping datasets from two published genome-wide association studies (GWASs). In the single-locus analysis, 76 SNPs were found to be significantly associated with CMSS (P < .050, false-positive report probability < 0.2 and Bayesian false discovery probability < 0.8) in the discovery dataset, of which seven SNPs were replicated in the validation dataset and three SNPs (HAL rs17676826T > C, LGSN rs12663017T > A, and NOXRED1 rs8012548A > G) independently predicted CMSS, with an effect-allele attributed adjusted hazards ratio of 1.52 (95% confidence interval = 1.19-1.93) and P < .001, 0.68 (0.54-0.87) and P = .002 and 0.62 (0.46-0.83) and P = .002, respectively. The model including the number of unfavorable genotypes (NUGs) of these three SNPs and covariates improved the five-year CMSS prediction (P = .012) than the one with other covariates only. Further expression quantitative trait loci (eQTL) analysis found that the LGSN rs12663017 A allele was significantly associated with increased messenger RNA (mRNA) expression levels (P = 8.89 × 10 -11 ) in lymphoblastoid cell lines of the 1000 Genomes Project database. In the analysis of the genotype tissue expression (GTEx) project datasets, HAL rs17676826 C and NOXRED1 rs8012548 G alleles were significantly associated with their mRNA expression levels in sun-exposed skin of the lower leg (P = 6.62 × 10-6 and 1.37 × 10-7 , respectively) and in sun-not-exposed suprapubic skin (P < .001 and 1.43 × 10-8 , respectively). Taken together, these genetic variants of glutamine-metabolic pathway genes may be promising predictors of survival in patients with CM.

Extremity nevus count is an independent risk factor for basal cell carcinoma and melanoma, but not squamous cell carcinoma.

BACKGROUND: The presence of nevi portends an increased risk for melanoma. OBJECTIVE: We sought to examine the association between extremity nevus count and the risk of melanoma and keratinocyte cancers. METHODS: We evaluated prospective cohorts of 176,317 women (the Nurses' Health Study, 1986-2012 and the Nurses' Health Study 2, 1989-2013) and 32,383 men (Health Professionals Follow-up Study, 1986-2012). Information on nevus count (none, 1-5, 6-14, ≥15) on the extremity was collected at baseline. RESULTS: There were 1704 incident cases of melanoma, 2296 incident cases of squamous cell carcinoma, and 30,457 incident cases of basal cell carcinoma, with a total of 4,655,043 person-years for melanoma and 4,267,708 person-years for keratinocyte cancers. The presence of an extremity nevus was associated with an increased risk of melanoma in all anatomic areas and increased risk of basal cell carcinoma (BCC). Individuals with ≥15 nevi had the highest risk of melanoma and BCC compared to those without any extremity nevi (melanoma hazard ratio 2.79 [95% confidence interval 2.04-3.83]; BCC HR 1.40 [95% confidence interval 1.32-1.49]). No significant association was observed for squamous cell carcinoma. LIMITATIONS: Limitations of our study included self-reported nevus count and detection bias. CONCLUSIONS: Extremity nevus count is a helpful clinical marker in risk-stratifying individuals for BCC and melanoma on all body sites.

Having a first-degree relative with melanoma increases lifetime risk of melanoma, squamous cell carcinoma, and basal cell carcinoma.

BACKGROUND: Previous studies have found familial aggregation of melanoma and keratinocyte cancers (KCs). OBJECTIVE: We sought to determine the risk of melanoma and KCs in those with a positive family history of melanoma while controlling for pigmentary and environmental risk factors. METHODS: We prospectively followed 216,115 participants from the Nurses' Health Study, Nurse's Health Study 2, and Health Professionals Follow-up Study for more than 20 years. Cox proportional hazards regression controlling for known risk factors for skin cancer was used to estimate association between family history of melanoma and melanoma and KCs. RESULTS: Compared with those without a family history of melanoma, individuals with a family history of melanoma had a 74% increased risk of melanoma (hazard ratio [HR], 1.74; 95% confidence interval [CI], 1.45-2.09), a 22% increased risk of squamous cell carcinoma (HR, 1.22; 95% CI, 1.06-1.40), and a 27% increased risk of basal cell carcinoma (HR, 1.27; 95% CI, 1.12-1.44). Family history of melanoma increased the risk of development of truncal melanoma in both sexes, extremity melanoma in women, and extremity squamous cell carcinoma in women. LIMITATIONS: Limitations of this study include self-reported family history and detection bias. CONCLUSION: Individuals with a family history of melanoma are at an increased risk of melanoma and KCs.