Association of Urinary N7-(1-hydroxyl-3-buten-1-yl) Guanine (EB-GII) Adducts and Butadiene-Mercapturic Acids with Lung Cancer Development in Cigarette Smokers

Approximately 10% of smokers will develop lung cancer. Sensitive predictive biomarkers are needed to identify susceptible individuals. 1,3-Butadiene (BD) is among the most abundant tobacco smoke carcinogens. BD is metabolically activated to 3,4-epoxy-1-butene (EB), which is detoxified via the glutathione conjugation/mercapturic acid pathway to form monohydroxybutenyl mercapturic acid (MHBMA) and dihydroxybutyl mercapturic acid (DHBMA). Alternatively, EB can react with guanine nucleobases of DNA to form N7-(1-hydroxyl-3-buten-1-yl) guanine (EB-GII) adducts. We employed isotope dilution LC/ESI-HRMS/MS methodologies to quantify MHBMA, DHBMA, and EB-GII in urine of smokers who developed lung cancer (N = 260) and matched smoking controls (N = 259) from the Southern Community Cohort (white and African American). The concentrations of all three biomarkers were significantly higher in smokers that subsequently developed lung cancer as compared to matched smoker controls after adjusting for age, sex, and race/ethnicity (p < 0.0001 for EB-GII, p < 0.0001 for MHBMA, and p = 0.0007 for DHBMA). The odds ratio (OR) for lung cancer development was 1.63 for MHBMA, 1.37 for DHBMA, and 1.97 for EB-GII, with a higher OR in African American subjects than in whites. The association of urinary EB-GII, MHBMA, and DHBMA with lung cancer status did not remain upon adjustment for total nicotine equivalents. These findings reveal that urinary MHBMA, DHBMA, and EB-GII are directly correlated with the BD dose delivered via smoking and are associated with lung cancer risk.

Integrating participants as partners in research governance and operations: an approach from the All of Us Research Program Engagement Core

OBJECTIVES

During the last two decades, researchers and funders increasingly recognised the value of engaging patients and communities in research. Despite progress, community engagement remains challenging. There are few examples of successful participant engagement in governance of large-scale research programmes. Here we describe efforts to engage participants as partners in new governance roles in the All of Us Research Program, a precision medicine research initiative which intends to enrol at least one million participants. Using intentional, participant-centric engagement strategies, the All of Us Engagement Core recruited and integrated a diverse group of participants into governance roles including Steering and Executive Committees. Evaluation measures included a survey to assess Consortium Members' readiness for participant engagement.

RESULTS

Over a 3-year period, all items on the survey increased (higher readiness). Of the 291 respondents to the 2021 survey, respondents most frequently agreed that participant perspectives are essential (100%), participants understand enough to contribute meaningfully (94%) and participants should be involved in setting goals (96%). Respondents least frequently agreed that participants should have an equal voice in Working Groups (75%), Steering Committee (69%) and Executive Committee (63%).

CONCLUSION

In conclusion, participants can be effectively integrated into large-scale research governance, which is associated with increased researcher readiness for engagement.

Genetic Sex Effects of Polycystic Ovary Syndrome Reveal Distinct Metabolic Etiology

Females with polycystic ovary syndrome (PCOS) have an increased risk of developing metabolic disorders such as insulin resistance, obesity, and type 2 diabetes (T2D). High-risk groups or individuals with a family history are more likely to have a greater genetic susceptibility to these diseases, which drastically increases their risk of developing other chronic health conditions. In this study, we systematically evaluated the bidirectional genetic burden of PCOS and its comorbidities among females and males. First, we analyzed the pleiotropic effects of the PCOS polygenic risk score (PRS), a measurement of genetic liability to PCOS, across 1,857 medical conditions recorded in the Vanderbilt University Medical Center electronic health record. We conducted a phenome-wide association study (PheWAS) adjusted for median age, sex, and genetic ancestry. In the European sex-combined model (n = 72,824), we observed that PCOS PRS was significantly (Bonferroni corrected p < 7.86e-06) associated with T2D (OR = 1.11, p = 8.75e-08) and hypertension (OR = 1.06, p = 1.13e-07) in addition to polycystic ovaries (OR = 1.11, p = 1.91e-07). In the sex-stratified model, we found that males (n = 32,022) with a higher PRS for PCOS were more likely to develop cardiovascular diseases (CVD) compared to females (n = 40,802) who had higher odds of developing T2D. Although we were underpowered to detect any phenome-wide significant effects in our African descent sample (n=15,283), uterine leiomyoma (OR = 1.24, p = 3.79e-03), osteoarthritis (OR = 1.21, p = 3.94e-03), and benign neoplasm of uterus (OR = 1.24, p = 4.00e-03) were the top three nominal significant results (p < 0.05) in females (n = 9,418). To understand the genetic relationships observed in the PheWAS, we used LD score regression to determine the genetic correlation between the phenotypes. We found that PCOS was positively correlated with T2D (rg = 31%), systolic blood pressure (rg = 12%), and pulse pressure (rg = 15%). However, we found no significant associations between the genetic risk of CVD and PCOS diagnosis in the European or African descent samples. Our findings show that the genetic architecture of PCOS has distinct metabolic sex differences, but the genetic risk of those comorbidities is not predictive of a PCOS diagnosis. This suggests that other drivers are contributing to the endocrine and cardiovascular comorbid signatures that underlie PCOS.

Characterizing the Clinical and Genetic Spectrum of Polycystic Ovary Syndrome in Electronic Health Records

CONTEXT

Polycystic ovary syndrome (PCOS) is one of the leading causes of infertility, yet current diagnostic criteria are ineffective at identifying patients whose symptoms reside outside strict diagnostic criteria. As a result, PCOS is underdiagnosed and its etiology is poorly understood.

OBJECTIVE

We aim to characterize the phenotypic spectrum of PCOS clinical features within and across racial and ethnic groups.

METHODS

We developed a strictly defined PCOS algorithm (PCOSkeyword-strict) using the International Classification of Diseases, ninth and tenth revisions and keywords mined from clinical notes in electronic health records (EHRs) data. We then systematically relaxed the inclusion criteria to evaluate the change in epidemiological and genetic associations resulting in 3 subsequent algorithms (PCOScoded-broad, PCOScoded-strict, and PCOSkeyword-broad). We evaluated the performance of each phenotyping approach and characterized prominent clinical features observed in racially and ethnically diverse PCOS patients.

RESULTS

The best performance came from the PCOScoded-strict algorithm, with a positive predictive value of 98%. Individuals classified as cases by this algorithm had significantly higher body mass index (BMI), insulin levels, free testosterone values, and genetic risk scores for PCOS, compared to controls. Median BMI was higher in African American females with PCOS compared to White and Hispanic females with PCOS.

CONCLUSIONS

PCOS symptoms are observed across a severity spectrum that parallels the continuous genetic liability to PCOS in the general population. Racial and ethnic group differences exist in PCOS symptomology and metabolic health across different phenotyping strategies.

African-specific improvement of a polygenic hazard score for age at diagnosis of prostate cancer

Polygenic hazard score (PHS) models are associated with age at diagnosis of prostate cancer. Our model developed in Europeans (PHS46) showed reduced performance in men with African genetic ancestry. We used a cross-validated search to identify single nucleotide polymorphisms (SNPs) that might improve performance in this population. Anonymized genotypic data were obtained from the PRACTICAL consortium for 6253 men with African genetic ancestry. Ten iterations of a 10-fold cross-validation search were conducted to select SNPs that would be included in the final PHS46+African model. The coefficients of PHS46+African were estimated in a Cox proportional hazards framework using age at diagnosis as the dependent variable and PHS46, and selected SNPs as predictors. The performance of PHS46 and PHS46+African was compared using the same cross-validated approach. Three SNPs (rs76229939, rs74421890 and rs5013678) were selected for inclusion in PHS46+African. All three SNPs are located on chromosome 8q24. PHS46+African showed substantial improvements in all performance metrics measured, including a 75% increase in the relative hazard of those in the upper 20% compared to the bottom 20% (2.47-4.34) and a 20% reduction in the relative hazard of those in the bottom 20% compared to the middle 40% (0.65-0.53). In conclusion, we identified three SNPs that substantially improved the association of PHS46 with age at diagnosis of prostate cancer in men with African genetic ancestry to levels comparable to Europeans.

SAT-024 Investigating Racial and Ethnic Comorbidity Patterns of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a highly heterogenous reproductive endocrine disorder that affects up to 15% of women and is one of the leading causes of infertility. However, its genetic etiology remains poorly understood. Additionally, PCOS patients have a greater risk of having metabolic disorders, such as insulin resistance and cardiovascular diseases, but it is estimated that up to 75% of women remain undiagnosed. Delayed treatment and care can exacerbate comorbid conditions and be detrimental to high risk populations like African American and Hispanic women. We aim to characterize genetic and environmental variables contributing to PCOS and understand its shared etiological features with metabolic disorders. To do this, we developed two algorithms to identify diverse PCOS patients using medical records. The broad algorithm used a combination of PCOS-related billing codes (Code Based) and identified a large dataset (N = 8,340) who exhibited diverse PCOS symptoms, while the strict algorithm required PCOS keywords in addition to billing codes (Regex Based). The strict algorithm identified a smaller cohort of patients (N = 4,593) who exhibited more classically diagnoseable PCOS characteristics according to Rotterdam and NIH criteria. Using both datasets, we tested PCOS case status against 1,853 phenotypes in the medical database using a logistic regression model and identified comorbidity patterns for women of European and African descent. We observed that European descent women consistently had more distinct phenotypes associated with PCOS case status than African American women. Next, we examined the interacting effects of self-reported race on PCOS case status and found four significant phenotypes (p < 6.25e-4) in our Regex Based algorithm. African American women with PCOS had greater odds of being diagnosed with “Early onset of delivery” (p = 1.3e-4, OR = 1.86), “Hereditary hemolytic anemias” (p =1.8e-4, OR = 0.65), and “Other hereditary hemolytic anemias” (p = 3.7e-04, OR = 0.90). Meanwhile, European descent women had greater odds of being diagnosed with “Hypertensive chronic kidney disease” (p = 1.7e-04, OR = 0.68). Results show that European and African American women have unique metabolic comorbidity patterns and it may also indicate that clinical PCOS diagnostic standards vary between these groups with possible disparity-causing effects.

Genome-wide association study confirms lung cancer susceptibility loci on chromosomes 5p15 and 15q25 in an African-American population

OBJECTIVES

Genome-wide association studies (GWAS) of lung cancer have identified regions of common genetic variation with lung cancer risk in Europeans who smoke and never-smoking Asian women. This study aimed to conduct a GWAS in African Americans, who have higher rates of lung cancer despite smoking fewer cigarettes per day when compared with Caucasians. This population provides a different genetic architecture based on underlying African ancestry allowing the identification of new regions and exploration of known regions for finer mapping.

MATERIALS AND METHODS

We genotyped 1,024,001 SNPs in 1737 cases and 3602 controls in stage 1, followed by a replication phase of 20 SNPs (p<1.51×10(-5)) in an independent set of 866 cases and 796 controls in stage 2.

RESULTS AND CONCLUSION

In the combined analysis, we confirmed two loci to be associated with lung cancer that achieved the threshold of genome-wide significance: 15q25.1 marked by rs2036527 (p=1.3×10(-9); OR=1.32; 95% CI=1.20-1.44) near CHRNA5, and 5p15.33 marked by rs2853677 (p=2.8×10(-9); OR=1.28; 95% CI=1.18-1.39) near TERT. The association with rs2853677 is driven by the adenocarcinoma subtype of lung cancer (p=1.3×10(-8); OR=1.37; 95% CI=1.23-1.54). No SNPs reached genome-wide significance for either of the main effect models examining smoking - cigarettes per day and current or former smoker. Our study was powered to identify strong risk loci for lung cancer in African Americans; we confirmed results previously reported in African Americans and other populations for two loci near plausible candidate genes, CHRNA5 and TERT, on 15q25.1 and 5p15.33 respectively, are associated with lung cancer. Additional work is required to map and understand the biological underpinnings of the strong association of these loci with lung cancer risk in African Americans.

Abstract C19: Assessing metformin use and ovarian cancer survival from electronic medical records

Background: Ovarian cancer is a rare disease with a poor prognosis. Type 2 Diabetes Mellitus (T2D) is associated with increased cancer risk and mortality. Metformin is a common first-line treatment for T2D that has been shown to have multiple anti-cancer effects. Repurposing metformin for ovarian cancer treatment is attractive, but associations between T2D, metformin use, and ovarian cancer survival have been evaluated in only a few studies to date.

Methods: Electronic medical record (EMR) data was abstracted for tumor registry confirmed ovarian and fallopian tube cancer cases from the Vanderbilt University Medical Center; MedEx was used to determine metformin use. Associations with T2D or metformin were evaluated with chi-square tests or Student's t-tests. Associations with overall survival were evaluated using Cox proportional hazards regression to compute Hazard Ratios (HR) and corresponding 95% Confidence Intervals (CI). Associations with and without adjustment for age, race, stage of disease, and histologic subtype were modeled. Kaplan-Meir functions were used to visualize survival functions; differences were evaluated via the log-rank test. For 50 subjects, we used natural language processing assisted manual review to assess metformin use; a Kappa coefficient was used to compare this to MedEx captured use.

Results: EMR data was available for 414 Tumor Registry confirmed cases; of these, 372 (89.9%) were invasive epithelial ovarian cancers. Of the 372 cases, 332 were non T2D ovarian cancer cases of which 47 (14.2%) were from minority population(s) (non-Caucasian). There were a total of 40 T2D ovarian cancer cases of which 7 (17.5%) were from minority population(s). There were more high stage (III & IV) cancers among T2D than non-T2D OC cases (P=0.032). T2D cases on metformin were taller and weighed more than T2D cases without metformin use (P=0.034 and P=0.044, respectively). Associations with overall survival were suggestive but non-significant for T2D (HR: 0.72, 95% CI: 0.47-1.08) and metformin use, either compared to T2D cases without metformin use (HR: 0.56, 95% CI: 0.23-1.39) or compared to all ovarian cancer cases (HR: 0.53, 95% CI: 0.27-1.05). MedEx captured and manually curated metformin use was highly concordant (Kappa=0.96).

Conclusions: We found that ovarian cancer cases with metformin use had marginally better overall survival than both T2D cases not taking metformin and all ovarian cancer cases. While not significant, these associations indicate that metformin may have utility clinically repurposed as a treatment for ovarian cancer. Finally, high agreement between MedEx captured and natural language processing assisted manually curated metformin use indicates that MedEx captured metformin use can be used in larger EMR studies.

Citation Format: Leshaun Clayton, Spencer Keene, Samantha P. Stansel, Min Jiang, Melinda Aldrich, Hua Xu, Jeremy Warner, Joshua Denny, Dineo Khabele, Alicia Beeghly-Fadiel. Assessing metformin use and ovarian cancer survival from electronic medical records. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr C19.

Abstract B17: Type 2 diabetes, metformin, and ovarian cancer survival: An analysis of tumor registry and electronic medical record data

Background: Type 2 Diabetes Mellitus (T2D) is associated with increased cancer risk and higher cancer mortality. Metformin, a common T2D treatment, is associated with improved survival for several cancers. With a five year survival of 42%, repurposing metformin to improve ovarian cancer prognosis is attractive. However, only a few studies to date have evaluated associations between T2D, metformin use, and ovarian cancer survival.

Methods: We evaluated tumor registry confirmed ovarian and fallopian tube cancer cases from the Vanderbilt University Medical Center. Metformin use was determined from electronic medical records (EMR) using MedEx. For validation, natural language processing EMR review was conducted for 50 subjects. Cox proportional hazards regression was used to evaluate associations with overall survival and calculate Hazard Ratios (HR) and corresponding 95% Confidence Intervals (CI); models included adjustment for age, stage, histologic subtype, and body-mass index (BMI).

Results: Tumor registry data and EMR was available for 372 invasive epithelial ovarian cancer cases. Forty (10.8%) had T2D, and 20 had metformin use (5.4%). MedEx and EMR reviewed metformin use was highly concordant (Kappa=0.96). Associations with overall survival were suggestive but non-significant for T2D (HR: 0.80, 95% CI: 0.51-1.25) and metformin use, either among only T2D cases (HR: 0.73, 95% CI: 0.29-1.84) or among all ovarian cancer cases (HR: 0.61, 95% CI: 0.31-1.21). Two or more years of metformin use was significantly associated with better survival compared to cases without metformin use (HR: 0.28, 95% CI: 0.09-0.89). Exploratory analyses suggested better survival among serous cases and worse survival among non-serous cases for both T2D and metformin, but associations were not significant. Analyses to address survival time bias yielded results comparable to our primary findings.

Conclusions: Ovarian cancer cases with metformin use had marginally better overall survival. While not significant, these associations indicate that metformin may have utility repurposed as a treatment for ovarian cancer. Larger studies are needed to determine if associations differ by histology, and if metformin may be beneficial to all ovarian cancer subtypes.

Citation Format: Spencer Keene, Samantha P. Stansel, Leshaun Clayton, Min Jiang, Melinda Aldrich, Hua Xu, Jeremy Warner, Joshua Denny, Dineo Khabele, Alicia Beeghly-Fadiel. Type 2 diabetes, metformin, and ovarian cancer survival: An analysis of tumor registry and electronic medical record data. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: Exploiting Vulnerabilities; Oct 17-20, 2015; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(2 Suppl):Abstract nr B17.

Imputation and subset-based association analysis across different cancer types identifies multiple independent risk loci in the TERT-CLPTM1L region on chromosome 5p15.33

Genome-wide association studies (GWAS) have mapped risk alleles for at least 10 distinct cancers to a small region of 63 000 bp on chromosome 5p15.33. This region harbors the TERT and CLPTM1L genes; the former encodes the catalytic subunit of telomerase reverse transcriptase and the latter may play a role in apoptosis. To investigate further the genetic architecture of common susceptibility alleles in this region, we conducted an agnostic subset-based meta-analysis (association analysis based on subsets) across six distinct cancers in 34 248 cases and 45 036 controls. Based on sequential conditional analysis, we identified as many as six independent risk loci marked by common single-nucleotide polymorphisms: five in the TERT gene (Region 1: rs7726159, P = 2.10 × 10(-39); Region 3: rs2853677, P = 3.30 × 10(-36) and PConditional = 2.36 × 10(-8); Region 4: rs2736098, P = 3.87 × 10(-12) and PConditional = 5.19 × 10(-6), Region 5: rs13172201, P = 0.041 and PConditional = 2.04 × 10(-6); and Region 6: rs10069690, P = 7.49 × 10(-15) and PConditional = 5.35 × 10(-7)) and one in the neighboring CLPTM1L gene (Region 2: rs451360; P = 1.90 × 10(-18) and PConditional = 7.06 × 10(-16)). Between three and five cancers mapped to each independent locus with both risk-enhancing and protective effects. Allele-specific effects on DNA methylation were seen for a subset of risk loci, indicating that methylation and subsequent effects on gene expression may contribute to the biology of risk variants on 5p15.33. Our results provide strong support for extensive pleiotropy across this region of 5p15.33, to an extent not previously observed in other cancer susceptibility loci.

Abstract 4149: Genetic variation in CYP2A6, a nicotine/nitrosamine metabolism enzyme, influences lung cancer risk in two independent case-control studies of African American smokers

We investigated the association of CYP2A6 genotype with lung cancer risk among African American smokers to further our understanding of cancer susceptibility within this high-risk population. CYP2A6 gene variants are hypothesized to modify lung cancer risk among cigarette smokers by influencing smoking amount, through altered nicotine inactivation, and/or by influencing the bioactivation of carcinogenic tobacco-specific nitrosamines.

Participants were African American smokers drawn from two independent lung cancer case-control studies: a study nested within the Southern Community Cohort Study, Vanderbilt University, Nashville, TN with 1-2 controls matched to each incident lung cancer case by age, sex and recruitment site (SCCS: n = 494), and a case-control study from the University of Texas MD Anderson Cancer Center, Houston, TX with controls frequency matched to cases by smoking history in addition to age and sex (MDA: n = 407). Genotyping was performed for 12 CYP2A6 reduced/null activity alleles, and participants with genotypes associated with a 25% or more reduction in CYP2A6 activity were pooled together as reduced metabolizers. Lung cancer risk was estimated through logistic regression modeling, which permitted adjustments for smoking.

Compared to the CYP2A6 normal metabolism genotype group, the reduced metabolism group was associated with a significant reduction in lung cancer risk in SCCS, MDA, and in the pooled studies (SCCS: Odds ratio [OR] 0.62, 95% confidence interval [CI] 0.43-0.90; MDA: OR 0.66, 95% CI 0.44-0.98; Pooled: OR 0.64, 95% CI 0.49-0.84; ORs adjusted for age and sex). The association remained significant following additional adjustments for cigarettes/day and years of smoking (SCCS: OR 0.58, 95% CI 0.39-0.87; MDA: OR 0.66, 95% CI 0.44-0.99; Pooled: OR 0.62, 95% CI 0.47-0.83). Stratified analyses within the pooled studies revealed a consistent degree of CYP2A6 genetic risk across categories of cigarettes/day (≤10 cig/day: OR 0.65, 95% CI 0.43-0.98; 11-20 cig/day: OR 0.58, 95% CI 0.37-0.91; &gt;20 cig/day: OR 0.64, 95% CI 0.29-1.44) and further assessment of CYP2A6 genotype and lung cancer risk according to smoking duration and current/former smoking status is ongoing. We also noted a significant interaction between CYP2A6 genotype and sex on the risk for lung cancer (SCCS: P=.03; MDA: P=.03; Pooled: P=.003) with a greater effect in men. Additional analyses are underway to explore potential contributing factors to the observed interaction.

Genetic variation in CYP2A6 contributes to lung cancer risk among African American smokers, whereby CYP2A6 genotypes associated with reduced metabolic activity confer a lower risk of developing lung cancer.

Citation Format: Catherine A. Wassenaar, Yuanqing Ye, Qiuyin Cai, Melinda Aldrich, Joanne Knight, Margaret R. Spitz, Xifeng Wu, William J. Blot, Rachel F. Tyndale. Genetic variation in CYP2A6, a nicotine/nitrosamine metabolism enzyme, influences lung cancer risk in two independent case-control studies of African American smokers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4149. doi:10.1158/1538-7445.AM2014-4149

Genome-wide association studies identify CHRNA5/3 and HTR4 in the development of airflow obstruction

RATIONALE

Genome-wide association studies (GWAS) have identified loci influencing lung function, but fewer genes influencing chronic obstructive pulmonary disease (COPD) are known.

OBJECTIVES

Perform meta-analyses of GWAS for airflow obstruction, a key pathophysiologic characteristic of COPD assessed by spirometry, in population-based cohorts examining all participants, ever smokers, never smokers, asthma-free participants, and more severe cases.

METHODS

Fifteen cohorts were studied for discovery (3,368 affected; 29,507 unaffected), and a population-based family study and a meta-analysis of case-control studies were used for replication and regional follow-up (3,837 cases; 4,479 control subjects). Airflow obstruction was defined as FEV(1) and its ratio to FVC (FEV(1)/FVC) both less than their respective lower limits of normal as determined by published reference equations.

MEASUREMENTS AND MAIN RESULTS

The discovery meta-analyses identified one region on chromosome 15q25.1 meeting genome-wide significance in ever smokers that includes AGPHD1, IREB2, and CHRNA5/CHRNA3 genes. The region was also modestly associated among never smokers. Gene expression studies confirmed the presence of CHRNA5/3 in lung, airway smooth muscle, and bronchial epithelial cells. A single-nucleotide polymorphism in HTR4, a gene previously related to FEV(1)/FVC, achieved genome-wide statistical significance in combined meta-analysis. Top single-nucleotide polymorphisms in ADAM19, RARB, PPAP2B, and ADAMTS19 were nominally replicated in the COPD meta-analysis.

CONCLUSIONS

These results suggest an important role for the CHRNA5/3 region as a genetic risk factor for airflow obstruction that may be independent of smoking and implicate the HTR4 gene in the etiology of airflow obstruction.

Abstract 662: Effect of tobacco smoking on the risks of childhood acute lymphocytic and myeloid leukemias, by phenotypic and cytogenetic subtype

Background: Tobacco smoke contains several myelotropic carcinogens (i.e., benzene, 1,3 butadiene and formaldehyde) and is strongly suspected of damaging pluripotential hematopoietic stem cells. Objective: To examine the role of tobacco smoking in the etiology of childhood acute lymphocytic leukemia (ALL) and myeloid leukemia (AML), defined by phenotypic feature and type of chromosomal aberrations at diagnosis, such as translocation t(12:21) or high hyperdiploidy (51+ chromosomes). Method: Children (0-14 years old) newly diagnosed with ALL (n=839) and AML (n=145) were enrolled in a case-control study in California (1995-2008). Population-based controls (n=1226) were matched to cases on age, sex, Hispanic status, and maternal race. Parents provided information on exposure to tobacco smoking before and after their child's birth. Conventional karyotype and fluorescence in situ hybridization (FISH) data were abstracted from the medical reports. Additional FISH assays using pre-treatment bone marrow specimens were conducted to complete cytogenetic classification. Unconditional logistic regression analyses were used to estimate the odds ratios (OR) and 95% confidence intervals (CI) for developing leukemia, using binary variable for ever/never smoked (ORbinary) and continuous variable for number of cigarettes smoked per day (ORcig). All models included the matching factors and household income. Results: In univariate analyses, elevated risks of B-cell ALL (n=722) were associated with pre-conception paternal smoking (“PCPS”) (ORcig= 1.02; 95% CI:1.00-1.03; p=0.04) and child's passive smoking (“CPS”) after birth (ORbinary=1.32; 95% CI:1.21-3.50; p=0.02). Analyses using mutually exclusive exposure variables (i.e., only “PCPS,” only “CPS,” and both “PCPS-CPS,” compared to no smoking) showed that the elevated risk of B-cell ALL was limited to children exposed to both “PCPS-CPS” (OR=1.50, 95% CI:1.10-2.04). The magnitude of this association increased for 133 B-cell ALL cases harboring chromosomal translocation t(12;21) (OR=2.37; 95% CI:1.41-4.01). Weaker associations were seen between “PCPS” and “CPS” and B-cell ALL harboring other chromosome translocations (n=82) or deletions (n=63). Tobacco smoking did not appear to be associated with hyperdiploid B-cell ALL (n=228) and T-cell ALL (n=70). Child's passive smoking conferred a 1.5-fold increased risk of AML (95% CI:0.98-2.26; p=0.06), with a higher risk observed for those with chromosome aberrations linked to a “favorable” prognosis (ORbinary=1.94; p=0.07; n=80). No excess risks were seen with maternal smoking during pregnancy, after accounting for other sources of smoking. Conclusions: Exposure to tobacco smoking is an important predictor of childhood ALL, and possibly AML. The observed risks contrast by phenotypic and cytogenetic subtype, providing insights in the etiology of the disease.

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 662. doi:1538-7445.AM2012-662

Lung cancer risk among smokers of menthol cigarettes

BACKGROUND

Menthol cigarettes, preferred by African American smokers, have been conjectured to be harder to quit and to contribute to the excess lung cancer burden among black men in the Unites States. However, data showing an association between smoking menthol cigarettes and increased lung cancer risk compared with smoking nonmenthol cigarettes are limited. The Food and Drug Administration is currently considering whether to ban the sale of menthol cigarettes in the United States.

METHODS

We conducted a prospective study among 85,806 racially diverse adults enrolled in the Southern Community Cohort Study during March 2002 to September 2009 according to cigarette smoking status, with smokers classified by preference for menthol vs nonmenthol cigarettes. Among 12,373 smokers who responded to a follow-up questionnaire, we compared rates of quitting between menthol and nonmenthol smokers. In a nested case-control analysis of 440 incident lung cancer case patients and 2213 matched control subjects, using logistic regression modeling we computed odds ratios (ORs) and accompanying 95% confidence intervals (CIs) of lung cancer incidence, and applied Cox proportional hazards modeling to estimate hazard ratios (HRs) of lung cancer mortality, according to menthol preference.

RESULTS

Among both blacks and whites, menthol smokers reported smoking fewer cigarettes per day; an average of 1.6 (95% CI = 1.3 to 2.0) fewer for blacks and 1.8 (95% CI = 1.3 to 2.3) fewer for whites, compared with nonmenthol smokers. During an average of 4.3 years of follow-up, 21% of participants smoking at baseline had quit, with menthol and nonmenthol smokers having equal odds of quitting (OR = 1.02, 95% CI = 0.89 to 1.16). A lower lung cancer incidence was noted in menthol vs nonmenthol smokers (for smokers of <10, 10-19, and ≥ 20 cigarettes per day, compared with never smokers, OR = 5.0 vs 10.3, 8.7 vs 12.9, and 12.2 vs 21.1, respectively). These trends were mirrored for lung cancer mortality. In multivariable analyses adjusted for pack-years of smoking, menthol cigarettes were associated with a lower lung cancer incidence (OR = 0.65, 95% CI = 0.47 to 0.90) and mortality (hazard ratio of mortality = 0.69, 95% CI = 0.49 to 0.95) than nonmenthol cigarettes.

CONCLUSIONS

The findings suggest that menthol cigarettes are no more, and perhaps less, harmful than nonmenthol cigarettes.

Train wrecks to typhoid fever: the development of railroad medicine organizations, 1850-World War I

From their beginning American railroads developed medical arrangements to care for the large number of workers and passengers they killed or injured. After the Civil War, both labor unrest and liability concerns led them to expand and formalize these arrangements, and three forms of organization arose. Western roads, facing an almost complete lack of medical facilities, developed employee-funded hospital organizations. In the east, companies created medical organizations under a salaried chief surgeon and contracted with local physicians to provide care. A third model, pioneered by the Baltimore & Ohio Railroad in the 1880s, devised a beneficial society that provided medical care and compensation for injured workers. Although these organizations involved both contract practice and group hospitalization, the AMA seems to have ignored them. In the 1880s railroad physicians developed their own organizations, including the National Association of Railway Surgeons, in which they discussed problems of professionalization and such medical matters as "railway spine." Concern with costs and labor turnover also led the carriers into preventive medicine. Some roads provided smallpox and typhoid vaccinations, campaigned against malaria, improved passenger-car sanitation, required physical examinations of their employees, and trained them in first aid. By World War I, railroad medical organizations provided care to nearly two million employees and employment to about 10 percent of all physicians.

The use of enzyme therapy to regulate the metabolic and phenotypic consequences of adenosine deaminase deficiency in mice. Differential impact on pulmonary and immunologic abnormalities

Adenosine deaminase (ADA) deficiency results in a combined immunodeficiency brought about by the immunotoxic properties of elevated ADA substrates. Additional non-lymphoid abnormalities are associated with ADA deficiency, however, little is known about how these relate to the metabolic consequences of ADA deficiency. ADA-deficient mice develop a combined immunodeficiency as well as severe pulmonary insufficiency. ADA enzyme therapy was used to examine the relative impact of ADA substrate elevations on these phenotypes. A "low-dose" enzyme therapy protocol prevented the pulmonary phenotype seen in ADA-deficient mice, but did little to improve their immune status. This treatment protocol reduced metabolic disturbances in the circulation and lung, but not in the thymus and spleen. A "high-dose" enzyme therapy protocol resulted in decreased metabolic disturbances in the thymus and spleen and was associated with improvement in immune status. These findings suggest that the pulmonary and immune phenotypes are separable and are related to the severity of metabolic disturbances in these tissues. This model will be useful in examining the efficacy of ADA enzyme therapy and studying the mechanisms underlying the immunodeficiency and pulmonary phenotypes associated with ADA deficiency.

A mutation in a case of early onset narcolepsy and a generalized absence of hypocretin peptides in human narcoleptic brains

We explored the role of hypocretins in human narcolepsy through histopathology of six narcolepsy brains and mutation screening of Hcrt, Hcrtr1 and Hcrtr2 in 74 patients of various human leukocyte antigen and family history status. One Hcrt mutation, impairing peptide trafficking and processing, was found in a single case with early onset narcolepsy. In situ hybridization of the perifornical area and peptide radioimmunoassays indicated global loss of hypocretins, without gliosis or signs of inflammation in all human cases examined. Although hypocretin loci do not contribute significantly to genetic predisposition, most cases of human narcolepsy are associated with a deficient hypocretin system.

Night time versus daytime transient ischaemic attack and ischaemic stroke: a prospective study of 110 patients

OBJECTIVE

Ischaemic stroke occurs only in 20%-40% of patients at night. The aim of the study was to compare sleep and stroke characteristics of patients with and without night time onset of acute ischaemic cerebrovascular events.

METHODS

A consecutive series of 110 patients with transient ischaemic attack (n=45) or acute ischaemic stroke (n=65) was studied prospectively by means of a standard protocol which included assessment of time of onset of symptoms, sleep, and stroke characteristics. An overnight polysomnography was performed after the onset of transient ischaemic attack/stroke in 71 patients. Stroke and sleep characteristics of patients with and without cerebrovascular events occurring at night (between midnight and 0600) were compared.

RESULTS

A night time onset of transient ischaemic attack or stroke was reported by 23 (21%) of 110 patients. Patients with daytime and night time events were similar in demographics; risk factors; associated vascular diseases; clinical and polysomnographic sleep characteristics (including severity of sleep apnoea); and stroke severity, aetiology, and outcome. Only the diastolic blood pressure at admission was significantly lower in patients with night time events (74 v 82 mm Hg, p=0.01).

CONCLUSIONS

Patients with night time and daytime transient ischaemic attack/stroke are similar in sleep and stroke characteristics. Diastolic hypotension may predispose to night time cerebrovascular events. Factors not assessed in this study probably account for the circadian variation in the frequency of transient ischaemic attack and acute ischaemic stroke.

Cyclosporin toxicity at therapeutic blood levels and cytochrome P-450 IIIA

A 40-year-old male liver allograft recipient had neurological dysfunction and renal failure while his cyclosporin blood levels were in the therapeutic range; these features recurred on rechallenge. The hypothesis that this toxic effect might have resulted from abnormal metabolism of cyclosporin by liver cytochrome P-450 IIIA was investigated with the [14C]erythromycin breath test, which is a measure of this enzyme's activity. P-450 IIIA activity was decreased compared with that in controls, including other liver transplant recipients. Pretreatment with rifampicin, an inducer of P-450 IIIA, increased enzyme activity. After treatment with rifampicin the patient could be rechallenged with cyclosporin at a dose almost twice that which had previously been toxic. The patient died during a second transplantation and the microsomal content of P-450 IIIA was found to be low in the first transplant.

Effects of continuous positive airway pressure on phasic events of REM sleep in patients with obstructive sleep apnea

In patients with obstructive sleep apnea and associated rapid-eye-movement (REM) sleep deprivation and disruption, the first night of nasal continuous positive airway pressure (CPAP) is often associated with increases in REM sleep time and REM density (REM rebound). The amount of REM rebound, however, varies considerably. We sought to characterize the magnitude of REM rebound and to determine what factors determine individual differences in REM rebound with initial CPAP treatment. Twenty-six patients with sleep apnea had a baseline nocturnal polysomnogram and a second night with a trial of CPAP. REM sleep time increased by 69% with CPAP, REM density increased by 73%, and REM activity by 169%. REM density was highest in the second REM period. Improvement in respiratory disturbance index with CPAP correlated significantly with increased minutes of REM sleep with CPAP. Of polysomnographic measures on the baseline night, change in minutes of REM sleep with CPAP correlated best with minimum oxygen saturation and to a lesser degree with respiratory disturbance index, and minutes of Stage 1 sleep. One possible explanation for the effect of hypoxemia on subsequent REM rebound is that some physiological functions of REM sleep may fail when oxygen saturation falls below a certain level.

Effect of patent ductus arteriosus on gentamicin pharmacokinetics in very low birth weight (less than 1,500 g) babies

The effect of patent ductus arteriosus (PDA) and its therapy on the pharmacokinetic disposition of gentamicin in very low birth weight neonates was studied. Twenty-four neonates weighing less than 1,500 g with PDA were compared to 16 patients without PDA. Patients with PDA had significantly greater apparent volumes of distribution (0.64 +/- 0.20 vs. 0.41 +/- 0.08 l/kg; p less than 0.001) and serum half-life (8.49 +/- 2.69 vs. 6.23 +/- 1.92 h; p less than 0.01). The total body clearance was not significantly different between the two groups (56 +/- 20 ml/kg/h with PDA vs. 50 +/- 24 ml/kg/h without PDA). In addition, 7 patients were studied before and after PDA closure. The apparent volume of distribution fell in every case (p = 0.02). A statistically significant effect on clearance and half-life was not found. These findings suggest that PDA increases extracellular fluid volume, but does not affect glomerular filtration rate adversely. Additionally, serum gentamicin concentrations must be reevaluated after PDA closure in premature neonates.

Exaggerated jaundice in Navajo neonates. The role of bilirubin production

We have explored further the mechanism of exaggerated neonatal hyperbilirubinemia in the Navajo by determining bilirubin production rates with measurements of endogenous carbon monoxide excretion. Navajo newborns had elevated serum bilirubin concentrations and endogenous carbon monoxide excretion measurements at 2 days of age compared with a Caucasian control population. These findings could not be explained by differences in gestational age, postnatal age, or hemoglobin concentration. We conclude that accentuated bilirubinemia in Navajo neonates is partially due to increased bilirubin production.

Amino acid sequence of protein B23 phosphorylation site

A major phosphopeptide labeled in vivo, was identified in nucleolar protein B23 (Mr/pI = 37,000/5.1) after tryptic digestion. This peptide was purified by high performance liquid chromatography using reverse-phase (C8 and C18) columns. The phosphopeptide contains 20 amino acids including 1 phosphoserine, 7 glutamic acids, and 4 aspartic acids. The amino acid sequence is: His-Leu-Val-Ala-Val-Glu-Glu-Asp-Ala-Glu-Ser(P)-Glu-Asp-Glu-Asp- Glu-Glu-Asp-Val-Lys. This amino acid sequence is similar to that of nucleolar phosphoprotein C23 (8 consecutive amino acids were identical), and to the regulatory subunit (RII) of cAMP-dependent protein kinase (7 consecutive amino acids were identical, which is phosphorylated by casein kinase II (Carmichael, D.F., Geahlen, R.L., Allen, S.M., and Krebs, E.G. (1982) J. Biol. Chem 257, 10440-10445). The regions near these phosphorylation sites are enriched with glutamic and aspartic acids, suggesting that this acidic amino acid cluster may be essential for kinase recognition.

Alterations in immunolocalization of the phosphoprotein B23 in HeLa cells during serum starvation

Bright nucleolar immunofluorescence was observed in HeLa S3 cells by immunostaining with a monoclonal antibody to the nucleolar phosphoprotein B23 (MW 37 kD/pI 5.1). After 48 h of incubation in a serum-free medium, the nucleolar fluorescence was diminished and a general nuclear immunofluorescence was observed. This change in localization of fluorescence indicated that protein B23 had migrated out of the nucleoli. No gross morphological change in nucleoli was observed by light microscopy and the immunolocalization of another nucleolar phosphoprotein, C23, was unaffected by serum deprivation. Relocation of protein B23 in nucleoli was observed after refeeding with serum-containing medium. This re-entry process was not observed after treatment with actinomycin D (50 ng/ml-5 micrograms/ml), but the process was unaffected by cycloheximide (0.2 mM). Quantitation of protein B23 in the nucleoli of the control (fed) or starved HeLa cells was done by ELISA immunoassay. A marked decrease in the amount of protein B23 occurred in the nucleoli of the starved cells (11.8 micrograms B23/mgDNA) as compared with the control nucleoli (20.8 micrograms B23/mgDNA). The amount of protein B23 in the nucleoplasm (excluding nucleoli) was 70% higher in the starved cells. Protein B23 was analysed by one- and two-dimensional PAGE. Three components of protein B23 with slightly different molecular weights and pIs (37 kD/5.1, 35 kD/5.1 and 35 kD/5.3) were observed in nucleoli. The lower molecular weight components were predominantly found in the nucleoplasm.

Detection of a 140 KDA nucleolar protein with an anti-PCNA autoantibody

To assess the numbers and types of PCNA (proliferating cell nuclear antigen) species, immunoprecipitation studies on HeLa cell, nuclear and nucleolar extracts were performed. A 140 KDa protein from HeLa nucleoli was immunoprecipitated by an autoantibody (E.B.) previously used to detect the proliferating cell nuclear antigens (PCNA). The 140 KDa protein was also detected in the nuclear extract of colon carcinoma cells (omega) labeled in vitro with 125I-Bolton Hunter reagent. When the growth of the colon carcinoma cells was inhibited by 1% N,N-dimethylformamide for two weeks, the 140 KDa protein was not detected which suggests this protein is associated with cell growth.

Oxytocin and neonatal hyperbilirubinemia. Studies of bilirubin production

We studied the effect of oxytocin induction or augmentation of labor on rates of bilirubin production in newborns at three different institutions. Bilirubin production, assessed quantitatively by the pulmonary excretion rate of carbon monoxide or qualitatively by the blood carboxyhemoglobin concentration, was not elevated when compared with appropriately matched control groups. Previous studies have implicated administration of large volumes of electrolyte-free dextrose solutions together with oxytocin as an important factor contributing to hemolysis in the infant. The mothers in our studies received minimal amounts of free water. We conclude that oxytocin induction or augmentation of labor does not result in neonatal hemolysis and subsequent hyperbilirubinemia when it is administered without large volumes of sodium-free intravenous solutions.

Effect of patent ductus arteriosus on lower extremity blood flow velocity patterns in preterm infants

We used a 20-MHz, range-gated, pulsed Doppler device to measure noninvasively femoral artery blood flow velocity patterns in 24 preterm infants with patent ductus arteriosus (PDA). Mean spatial flow velocity and its temporal average were recorded by illumination of the entire flow stream. Peak systolic forward flow velocity (Vs), peak diastolic retrograde flow velocity (VD), mean flow velocity (Vf), and the peak to peak-mean velocity ratio, (VS-VD)/Vf, were determined serially in each patient. The changes in the femoral flow velocity pattern preceded or coincided with other evidence of ductal left to right shunting. Prior to PDA closure, (VS-VD)/Vf averaged 14.1 and Vf averaged 4.4 cm/sec; after ductal closure, (VS-VD)/Vf fell to 3.7 (P less than .001) and Vf rose to 9.1 cm/sec, more than twice the preclosure value (P less than .001). Large diastolic reverse flow velocity vectors and low mean velocity correlated with large left to right PDA shunts estimated from other methods of assessment. The noninvasive femoral artery Doppler approach detects patency of the ductus early in life, reflects left to right shunting in diastole, and emphasizes the impact of the PDA on systemic blood flow.

Noninvasive measurement of cardiac output in healthy preterm and term newborn infants

Although values for cardiac output in the newborn infant have been reported previously, the methods utilized have been invasive. To assess if cardiac output could be determined noninvasively in the neonate, we measured mean ascending aortic blood flow velocity (VAo) in well newborns using a portable 5MHz, range gated, pulsed Doppler velocity meter. Measurements were made from a suprasternal approach in 8 preterm (mean birth weight 1718 gm; mean estimated gestation age 33.3 weeks) and 14 term (mean birthweight 3127 gm; mean EGA 39.8 weeks) healthy infants under one week of age. The internal ascending aortic systolic diameter was determined echographically and aortic cross sectional area was calculated: AAo = pi d2/4. Ascending aortic blood flow (QAo) was then computed as QAo (ml/min) = VAo (cm/sec) X AAo (cm2) X 60 (sec/min). With the exclusion of patent ductus arteriosus (PDA) and detectable intracardiac defects, QAo was taken to equal cardiac output. Flow determinations were normalized to body weight. The 8 preterm infants had a mean cardiac output of 221 +/- 56 (+/- SD) ml/min/kg. The 14 term infants had a similar mean cardiac output of 236 +/- 47 ml/min/kg. The mean cardiac output of all 22 infants was 230 +/- 50. This study establishes normal values for cardiac output determined noninvasively by the Doppler technique, in the first week of life in healthy infants. These values are similar to previously reported systemic blood flows, which were determined by cardiac catheterization and thermodilution methods in healthy newborn infants.

Mortality from byssinosis among New England cotton mill workers, 1905-1912

Little was known about mortality from byssinosis among American cotton mill workers until recent times. Between 1912 and 1919, the Labor Department published two detailed investigations of mortality by cause of death among cotton mill workers and other residents of several New England mill towns. Statistical tests reveal no significant difference in mortality rates from nontubercular respiratory diseases between cotton textile workers and other mill town residents. Even when ex-mill workers who may have died from mill-related respiratory ailments are added to work-related deaths and subtracted from the control group, mortality rates do not differ significantly. Finally, when mortality rates for workers in the most dusty areas of the mills--picking and carding--are compared with those of other Fall River, Mass., residents, the differences are still not statistically significant. Apparently byssinosis was not a cause of excess mortality among New England cotton mill workers at the turn of the century.

Spinal cord swelling and candidiasis. A case report

Fusiform swelling of the spinal cord was noted myelographically in a patient with Hodgkin's disease. Autopsy revealed that the swelling was caused by Candida infection of the spinal cord. It is suggested that fungal infection be included in the differential diagnosis of spinal cord swelling in the immunosuppressed cancer patient.

Determinants of mortality among New England cotton mill workers during the Progressive era

Multiple regression analysis reveals that work in New England cotton textile mills during 1905–1912 raised age-adjusted mortality rates over those of non-mill- workers, and that worker mortality increased with years of mill experience. Mortality varied among groups because of differential self selection. Central age group native males with broad occupational choices had lower mortality rates than control groups. Young males, women, and the foreign born had restricted occupational choices. Hence they were less self selected and experienced higher mortality. Death rates were highest among married women workers who bore children. The combination of homework and millwork worsened their health and raised their mortality rates.