Timing of HPV16-E6 antibody seroconversion before OPSCC: findings from the HPVC3 consortium

BACKGROUND

Human papillomavirus type 16 (HPV16)-E6 antibodies are detectable in peripheral blood before diagnosis in the majority of HPV16-driven oropharyngeal squamous cell carcinoma (OPSCC), but the timing of seroconversion is unknown.

PATIENTS AND METHODS

We formed the HPV Cancer Cohort Consortium which comprises nine population cohorts from Europe, North America and Australia. In total, 743 incident OPSCC cases and 5814 controls provided at least one pre-diagnostic blood sample, including 111 cases with multiple samples. Median time between first blood collection and OPSCC diagnosis was 11.4 years (IQR = 6-11 years, range = 0-40 years). Antibodies against HPV16-E6 were measured by multiplex serology (GST fusion protein based Luminex assay).

RESULTS

HPV16-E6 seropositivity was present in 0.4% of controls (22/5814; 95% CI 0.2% to 0.6%) and 26.2% (195/743; 95% CI 23.1% to 29.6%) of OPSCC cases. HPV16-E6 seropositivity increased the odds of OPSCC 98.2-fold (95% CI 62.1-155.4) in whites and 17.2-fold (95% CI 1.7-170.5) in blacks. Seropositivity in cases was more frequent in recent calendar periods, ranging from 21.9% pre-1996 to 68.4% in 2005 onwards, in those with blood collection near diagnosis (lead time <5 years). HPV16-E6 seropositivity increased with lead time: 0.0%, 13.5%, 23.7%, and 38.9% with lead times of >30 years (N = 24), 20-30 years (N = 148), 10-20 years (N = 228), and <10 years (N = 301 cases) (p-trend < 0.001). Of the 47 HPV16-E6 seropositive cases with serially-collected blood samples, 17 cases seroconverted during follow-up, with timing ranging from 6 to 28 years before diagnosis. For the remaining 30 cases, robust seropositivity was observed up to 25 years before diagnosis.

CONCLUSIONS

The immune response to HPV16-driven tumorigenesis is most often detectable several decades before OPSCC diagnosis. HPV16-E6 seropositive individuals face increased risk of OPSCC over several decades.

Vitamin B6 catabolism and lung cancer risk: results from the Lung Cancer Cohort Consortium (LC3)

BACKGROUND

Increased vitamin B6 catabolism related to inflammation, as measured by the PAr index (the ratio of 4-pyridoxic acid over the sum of pyridoxal and pyridoxal-5'-phosphate), has been positively associated with lung cancer risk in two prospective European studies. However, the extent to which this association translates to more diverse populations is not known.

MATERIALS AND METHODS

For this study, we included 5323 incident lung cancer cases and 5323 controls individually matched by age, sex, and smoking status within each of 20 prospective cohorts from the Lung Cancer Cohort Consortium. Cohort-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between PAr and lung cancer risk were calculated using conditional logistic regression and pooled using random-effects models.

RESULTS

PAr was positively associated with lung cancer risk in a dose-response fashion. Comparing the fourth versus first quartiles of PAr resulted in an OR of 1.38 (95% CI: 1.19-1.59) for overall lung cancer risk. The association between PAr and lung cancer risk was most prominent in former smokers (OR: 1.69, 95% CI: 1.36-2.10), men (OR: 1.60, 95% CI: 1.28-2.00), and for cancers diagnosed within 3 years of blood draw (OR: 1.73, 95% CI: 1.34-2.23).

CONCLUSION

Based on pre-diagnostic data from 20 cohorts across 4 continents, this study confirms that increased vitamin B6 catabolism related to inflammation and immune activation is associated with a higher risk of developing lung cancer. Moreover, PAr may be a pre-diagnostic marker of lung cancer rather than a causal factor.

No association between circulating concentrations of vitamin D and risk of lung cancer: an analysis in 20 prospective studies in the Lung Cancer Cohort Consortium (LC3)

Background

There is observational evidence suggesting that high vitamin D concentrations may protect against lung cancer. To investigate this hypothesis in detail, we measured circulating vitamin D concentrations in prediagnostic blood from 20 cohorts participating in the Lung Cancer Cohort Consortium (LC3).

Patients and methods

The study included 5313 lung cancer cases and 5313 controls. Blood samples for the cases were collected, on average, 5 years before lung cancer diagnosis. Controls were individually matched to the cases by cohort, sex, age, race/ethnicity, date of blood collection, and smoking status in five categories. Liquid chromatography coupled with tandem mass spectrometry was used to separately analyze 25-hydroxyvitamin D2 [25(OH)D2] and 25-hydroxyvitamin D3 [25(OH)D3] and their concentrations were combined to give an overall measure of 25(OH)D. We used conditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for 25(OH)D as both continuous and categorical variables.

Results

Overall, no apparent association between 25(OH)D and risk of lung cancer was observed (multivariable adjusted OR for a doubling in concentration: 0.98, 95% CI: 0.91, 1.06). Similarly, we found no clear evidence of interaction by cohort, sex, age, smoking status, or histology.

Conclusion

This study did not support an association between vitamin D concentrations and lung cancer risk.

Gravity-driven instability of a thin liquid film underneath a soft solid

The gravity-driven instability of a thin liquid film located underneath a soft solid material is considered. The equations and boundary conditions governing the solid deformation are systematically converted from a Lagrangian representation to an Eulerian representation, which is the natural framework for describing the liquid motion. This systematic conversion reveals that the continuity-of-velocity boundary condition at the liquid-solid interface is more complicated than has previously been assumed, even in the small-strain limit. We then make clear the conditions under which the commonly used simplified version of this boundary condition is valid. The small-strain approximation, lubrication theory, and linear stability analysis are applied to derive an expression for the growth rate of small-amplitude perturbations. Asymptotic analysis reveals that the coupling between the liquid and solid manifests itself as a lower effective liquid-air interfacial tension that leads to larger instability growth rates. Although this suggests that it is more difficult to maintain a stable liquid coating underneath a soft solid, the effect is expected to be weak for cases of practical interest.

Effects of α-tocopherol and β-carotene supplementation on liver cancer incidence and chronic liver disease mortality in the ATBC study

Background:

Recent data suggest the possible benefits of α-tocopherol and β-carotene supplementation on liver cancer and chronic liver disease (CLD), but the long-term trial data are limited.

Methods:

We evaluated the efficacy of supplemental 50 mg day⁻¹α-tocopherol and 20 mg day⁻¹β-carotene on incident liver cancer and CLD mortality in a randomised trial of 29 105 Finnish male smokers, who received supplementation for 5–8 years and were followed for 16 additional years for outcomes.

Results:

Supplemental α-tocopherol, β-carotene, or both, relative to placebo, did not reduce the risk of liver cancer or CLD, either overall, during the intervention or during the post-intervention period.

Conclusions:

Long-term supplemental α-tocopherol or β-carotene had no effect on liver cancer or CLD mortality over 24 years of follow-up.

Hypertension, pulse, and other cardiovascular risk factors and vitamin D status in Finnish men

BACKGROUND

Debate exists about the relationship between hypovitaminosis D and cardiovascular (CVD) risk.

METHODS

This study investigated baseline (n=2,271) 25-hydroxyvitamin D (25(OH)D) and baseline and 4 year (n=1,957) CVD risk in a cohort of Finnish middle-aged male smokers.

RESULTS

The prevalences of measured hypertension, high pulse rate, diabetes, and coronary heart disease were 63%, 16%, 5%, and 10% at baseline and were 64%, 20%, 6%, and 16% at 4 years after baseline. The mean 25(OH)D was 41±18 nmol/L. At baseline, systolic blood pressure (β = -0.048; P = 0.02), and pulse rate (β = -0.043; P = 0.04) were both associated with lower 25(OH)D levels but not coronary heart disease or diabetes prevalence. On remeasuring CVD risk 4 years after baseline, the only significant association with baseline 25(OH)D levels was high pulse rate (β = -0.077; P = 0.001). In addition, a higher 25(OH)D level at baseline was associated with a change in pulse rate (β = -0.055; P = 0.01). These trends for hypertension (baseline) and high pulse rate (baseline and 4 years after baseline) were also seen on adjusted categorical analysis (P trend < 0.05).

CONCLUSIONS

Vitamin D deficiency at baseline was associated with hypertension in Finnish male smokers, but not after 4 years. These results are consistent with recent findings in other large cohort studies with measured blood pressure. Change in pulse rate over time continued to be significantly associated with lower 25(OH)D baseline levels; this new finding should be investigated further.

The association of coffee intake with liver cancer incidence and chronic liver disease mortality in male smokers

Background:

Coffee intake is associated with reduced risk of liver cancer and chronic liver disease as reported in previous studies, including prospective ones conducted in Asian populations where hepatitis B viruses (HBVs) and hepatitis C viruses (HCVs) are the dominant risk factors. Yet, prospective studies in Western populations with lower HBV and HCV prevalence are sparse. Also, although preparation methods affect coffee constituents, it is unknown whether different methods affect disease associations.

Methods:

We evaluated the association of coffee intake with incident liver cancer and chronic liver disease mortality in 27 037 Finnish male smokers, aged 50–69, in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, who recorded their coffee consumption and were followed up to 24 years for incident liver cancer or chronic liver disease mortality. Multivariate relative risks (RRs) and 95% confidence intervals (CIs) were estimated by Cox proportional hazard models.

Results:

Coffee intake was inversely associated with incident liver cancer (RR per cup per day=0.82, 95% CI: 0.73–0.93; P-trend across categories=0.0007) and mortality from chronic liver disease (RR=0.55, 95% CI: 0.48–0.63; P-trend<0.0001). Inverse associations persisted in those without diabetes, HBV- and HCV-negative cases, and in analyses stratified by age, body mass index, alcohol and smoking dose. We observed similar associations for those drinking boiled or filtered coffee.

Conclusion:

These findings suggest that drinking coffee may have benefits for the liver, irrespective of whether coffee was boiled or filtered.

Pigmentation-related phenotypes and risk of prostate cancer

BACKGROUND

Solar ultraviolet radiation exposure has been inversely related to prostate cancer incidence and mortality, possibly mediated through vitamin D status. Pigmentation-related traits influence endogenous vitamin D synthesis and may alter risk of prostate cancer.

METHODS

We examined prostate cancer in relation to hair and eye colour, and skin phototype in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study cohort. Incident cancer was diagnosed in 1982 out of 20 863 men. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated from Cox proportional hazards models.

RESULTS

Prostate cancer risk did not differ by eye colour or skin phototype. Men with naturally red hair were significantly less likely to develop prostate cancer (HR=0.46, 95% CI 0.24-0.89) than men with light brown hair (reference).

CONCLUSION

The red hair phenotype, which results from polymorphisms in the melanocortin-1-receptor (MC1R) gene, is associated with lower risk of prostate cancer. This pigmentation-related trait may influence prostate cancer development either directly, through genetic effects or regulatory mechanisms related to MC1R, another nearby gene, or other pigmentation genes, or indirectly, through associations with other exposures such as sunlight or vitamin D status.

An asymptotically consistent approximant method with application to soft- and hard-sphere fluids

A modified Padé approximant is used to construct an equation of state, which has the same large-density asymptotic behavior as the model fluid being described, while still retaining the low-density behavior of the virial equation of state (virial series). Within this framework, all sequences of rational functions that are analytic in the physical domain converge to the correct behavior at the same rate, eliminating the ambiguity of choosing the correct form of Padé approximant. The method is applied to fluids composed of "soft" spherical particles with separation distance r interacting through an inverse-power pair potential, φ = ε(σ∕r)(n), where ε and σ are model parameters and n is the "hardness" of the spheres. For n < 9, the approximants provide a significant improvement over the 8-term virial series, when compared against molecular simulation data. For n ≥ 9, both the approximants and the 8-term virial series give an accurate description of the fluid behavior, when compared with simulation data. When taking the limit as n → ∞, an equation of state for hard spheres is obtained, which is closer to simulation data than the 10-term virial series for hard spheres, and is comparable in accuracy to other recently proposed equations of state. By applying a least square fit to the approximants, we obtain a general and accurate soft-sphere equation of state as a function of n, valid over the full range of density in the fluid phase.

Influence of vitamin D binding protein on the association between circulating vitamin D and risk of bladder cancer

Background:

There is little research investigating the role of vitamin D binding protein (DBP) in the association between 25-hydroxyvitamin D (25(OH)D) and disease risk.

Methods:

Within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, 250 bladder cancer cases were randomly sampled and matched 1:1 to controls on age and date of blood collection. Odds ratios (OR) and 95% confidence intervals (CI) of bladder cancer were estimated by quartiles of DBP (measured by ELISA), 25(OH)D and the molar ratio of 25(OH)D:DBP, a proxy for free circulating 25(OH)D. Analyses were also conducted stratifying 25(OH)D by DBP (median split) and vice versa.

Results:

We found no direct association between circulating DBP levels and bladder cancer risk (P-trend=0.83). The inverse association between 25(OH)D and bladder cancer risk was unchanged after adjustment for DBP (Q4 vs Q1 OR=0.61, 95% CI=0.36–1.05; P-trend=0.04), and was stronger among men with lower DBP (low DBP: 25(OH)D Q4 vs Q1 OR=0.47, 95% CI=0.23–1.00; high DBP: 25(OH)D Q4 vs Q1 OR=0.83, 95% CI=0.40–1.75; P for interaction=0.11).

Conclusion:

Our findings provide additional support for an aetiologic role for vitamin D in bladder cancer and suggest that free, rather than total, circulating vitamin D may be a more relevant exposure when examining bladder and, perhaps, other cancers.

Abstract LB-337: Synergistic effects of twelve common genetic polymorphisms and smoking habits on absolute risk of bladder cancer

Smoking is the strongest established risk factor for bladder cancer and recent studies have identified multiple common susceptibility loci for this disease. Evaluation of gene-smoking interactions on absolute risk of bladder cancer could be important for understanding both the public health and biological significance of the combined effect of these factors. However, previous studies of gene-environment interactions focused on relative rather than absolute risk measures and thus did not address this important question. The aim of our analyses was to estimate absolute risk of bladder cancer in relation to smoking habits and 12 known susceptibility variants for this disease, and to evaluate if smoking risk differences (RD) vary by levels of a polygenic risk score derived from these variants, using additive tests for interaction. Analyses were based on data from 4,098 cases and 5,995 controls of European background in eight studies participating in the NCI bladder cancer genome-wide association study (GWAS). Absolute risks were estimated based on US incidence and mortality data. The main outcome measures were 30-year cumulative absolute risk of bladder cancer and RDs for males aged 50 years in relation to smoking habits and the polygenic risk score. RDs for ever compared to never smokers were significantly larger (P-additive interaction &lt; 0.05) for subjects carrying risk alleles for seven out of 12 known susceptibility variants. Polymorphisms in two detoxification enzymes, NAT2 and UGT1A6, provided the strongest evidence of additive interactions (P-additive interaction of 0.0002 and 0.0003, respectively), supporting the presence of biological interactions between smoking and these variants. The 30-year risk of bladder cancer in never, former and current smokers was 0.7%, 1.6% and 3.7%, respectively, for subjects in the bottom quartile of the polygenic risk score, compared to 2.0%, 5.1% and 8.0% for subjects in the top quartile. This translates into a significantly larger number of projected cases, which could be avoided by smoking prevention in subjects at higher compared to lower genetic risk (P-additive (2df)=4.6x10-9 for top to bottom quartile of the polygenic risk score). In conclusion, our analyses provide strong evidence for synergistic effects of smoking and known susceptibility loci for bladder cancer on the absolute risk of the disease. This indicates that targeting intense smoking prevention efforts to individuals at elevated genetic risk for bladder cancer could improve the public health impact of such efforts. However, genetic susceptibility for other smoking-related diseases, as well as practical and ethical considerations, would need to be taken into account before any recommendations could be made. (MGC, NR are Co-first authors; N.C. and DTS are Co-last authors)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-337. doi:1538-7445.AM2012-LB-337

Is dietary fat, vitamin D, or folate associated with pancreatic cancer?

Although potentially modifiable risk factors for pancreatic cancer include smoking, obesity, and diabetes, less is known about the extent to which diet affects cancer risk. Recent studies have demonstrated some consistency for dietary fat being associated with elevated pancreatic cancer risk, particularly from animal sources. However, less is known about which fatty acids pose the greatest risk. Vitamin D, due to its endogenous production following UV-B exposure, is a unique risk factor in that researchers have created several methods to assess its exposure in humans. Studies that measured vitamin D exposure differently have shown inconsistent results. Dietary studies suggest protective associations, whereas studies of circulating 25-hydroxyvitamin D status show null or positive associations with low or very high concentrations, respectively. Several, but not all epidemiologic studies provide evidence of an inverse relationship between total and/or dietary folate and risk of pancreatic cancer. Protective associations for circulating folate are more often observed among populations with inadequate status. This article reviews the current epidemiological and experimental evidence investigating the relationship of dietary fat, vitamin D, and folate with pancreatic cancer. Additionally the mechanisms by which these risk factors may contribute to cancer, the methodological challenges involved with assessing risk, and other obstacles encountered when ascertaining the magnitude and direction of these three exposures are discussed.

Predictors of vitamin D biochemical status in a large sample of middle-aged male smokers in Finland

BACKGROUND/OBJECTIVES

As vitamin D deficiency is considered to be more common in regions with little solar ultraviolet (UV) light in winter, the aim of this study was to analyze predictors of vitamin D status by season within a large sample of male smokers from Finland, a country where there is negligible solar UV light in winter.

SUBJECTS/METHODS

Vitamin D (measured by 25-hydroxyvitamin D (25(OH)D) nmol/l) and other serum constituents were assayed. Measured anthropometry, and self-reported dietary intake and physical activity (PA) were obtained and analyzed using stepwise multiple linear and logistic regression in 2271 middle-aged Finnish male smokers.

RESULTS

In all, 27% of the population in winter and 17% in summer had serum 25(OH)D levels of <25 nmol/l, respectively. In summer, in multiple logistic regression analyses with adjustment for confounding and other predictors, high vitamin D intake (odds ratios (OR) 3.6; 95% confidence interval (CI) 1.5-8.5), some leisure time PA (OR 2.0; 95% CI 1.3-3.1) and having a body mass index (BMI) of >or=21 kg/m(2) compared with <21 kg/m(2) (OR 2.6; 95% CI 1.3-5.0), were associated with 25(OH)D >or=25 nmol/l. In winter, additional modifiable factors were occupational PA (OR 1.6; 95% CI 1.1-2.5) and high fish (OR 3.1; 95% CI 1.7-6.2) or poultry consumption (OR 1.7; 95% CI 1.2-2.5). Predictors from linear regression analyses of continuous levels of 25(OH)D were similar to the logistic regression analyses of 25(OH)D >or=25 nmol/l.

CONCLUSION

In this Finnish sample more vitamin D intake, PA and having a BMI of >or=21 may have important modifiable roles in maintaining an adequate vitamin D status.

Low serum and red blood cell folate are moderately, but nonsignificantly associated with increased risk of invasive cervical cancer in U.S. women

Previous observational epidemiologic studies of folate and cervical cancer, as well as folate supplementation trials for cervical dysplasia, have produced mixed results. We examined the relationship between serum and RBC folate and incident invasive cervical cancer in a large, multicenter, community-based case-control study. Detailed in-person interviews were conducted, and blood was drawn at least 6 mo after completion of cancer treatment from 51% of cases and 68% of controls who were interviewed. Blood folate was measured with both microbiologic and radiobinding assays. Included in the final analyses were 183 cases and 540 controls. Logistic regression was used to control for all accepted risk factors, including age, sexual behavior, smoking, oral contraceptive use, Papanicolaou smear history and human papillomavirus (HPV)-16 serology. For all four folate measures, the geometric mean in cases was lower than in controls (e.g., 11.6 vs. 13.0 nmol/L, P < 0.01 for the serum radiobinding assay). Folate measures using microbiologic and radiobinding assays were correlated (serum: r = 0.90; RBC: r = 0.77). For serum folate, multivariate-adjusted odds ratios (OR) in the lowest vs. highest quartile were 1.3 [95% confidence interval (CI) = 0.8--2.9] and 1.6 (0.9--2.9), using the microbiologic and radiobinding assays, respectively. For RBC folate, comparable OR were 1.2 (0.6--2.2) and 1.5 (0.8--2.7). Similar risks were obtained when restricting analyses to subjects with a history of HPV infection. Thus, low serum and RBC folate were each moderately, but nonsignificantly, associated with increased invasive cervical cancer risk. These findings support a role for one-carbon metabolism in the etiology of cervical cancer.

Elevated serum homocysteine levels and increased risk of invasive cervical cancer in US women

OBJECTIVES

To explore the relationship between serum homocysteine, a sensitive biomarker for folate inadequacy and problems in one-carbon metabolism, and invasive cervical cancer.

METHODS

A large case-control study was conducted in five US areas with up to two community controls, obtained by random-digit dialing, individually matched to each case. Cervical cancer risk factors were assessed through at-home interview. Blood was drawn at least 6 months after completion of cancer treatment from 51% and 68% of interviewed cases and controls. Serum homocysteine was measured by high-performance liquid chromatography, and exposure to human papillomavirus (HPV) type 16, the most prevalent oncogenic type, was assessed using an enzyme-linked immunosorbent assay. Cases with advanced cancer and/or receiving chemotherapy were excluded, leaving 183 cases and 540 controls.

RESULTS

Invasive cervical cancer risk was substantially elevated for women in the upper three homocysteine quartiles (> 6.31 micromol/L); multivariate-adjusted odds ratios ranged from 2.4 to 3.2 (all 95% CIs excluded 1.0). A trend was apparent and significant (p = 0.01). When cases were compared with HPV-16 seropositive controls only, odds ratios were comparable.

CONCLUSIONS

Serum homocysteine was strongly and significantly predictive of invasive cervical cancer risk. This association could reflect folate, B12 and/or B6 inadequacy, or genetic polymorphisms affecting one-carbon metabolism.

Accounting and accountability: observations on the AHERF settlements

Recent enforcement proceedings involving health care and accounting--relating primarily to the Allegheny Health, Education and Research Foundation (AHERF)--have sparked renewed interest in the activities of the U.S. Securities and Exchange Commission in the municipal securities market. Officials and accountants who are working for public-sector issuers in the healthcare industry have responsibilities under the Federal securities laws. Other issues of relevance include disclosure in the secondary market as well as upon initial issuance, and the significance of antifraud actions in other areas.

Single session treatment for bleeding hemorrhoids

Fifty consecutive outpatients with bleeding internal hemorrhoids were prospectively treated with a single application of rubber band ligation or infrared coagulation. Complete follow-up observation was obtained in 48 patients (23 underwent rubber band ligation and 25 underwent infrared coagulation). At one month after treatment, 22 patients who underwent rubber band ligation and 16 who underwent infrared coagulation, were symptomatically improved (p less than 0.05). At six months, 15 patients who had undergone rubber band ligation and ten who had infrared coagulation treatment, remained improved (p less than 0.05). There was no statistical difference in the discomfort experienced by either group during or after the procedure as determined by a self-assessment scale. Two patients who underwent rubber band ligation experienced complications--a thrombosed external hemorrhoid developed in one patient and another had delayed rectal bleeding. Although associated with occasional complications after treatment, rubber band ligation is more effective than in infrared coagulation for single session treatment of bleeding internal hemorrhoids.