Risk of Breast Cancer Among Carriers of Pathogenic Variants in Breast Cancer Predisposition Genes Varies by Polygenic Risk Score

PURPOSE

This study assessed the joint association of pathogenic variants (PVs) in breast cancer (BC) predisposition genes and polygenic risk scores (PRS) with BC in the general population.

METHODS

A total of 26,798 non-Hispanic white BC cases and 26,127 controls from predominately population-based studies in the Cancer Risk Estimates Related to Susceptibility consortium were evaluated for PVs in BRCA1, BRCA2, ATM, CHEK2, PALB2, BARD1, BRIP1, CDH1, and NF1. PRS based on 105 common variants were created using effect estimates from BC genome-wide association studies; the performance of an overall BC PRS and estrogen receptor-specific PRS were evaluated. The odds of BC based on the PVs and PRS were estimated using penalized logistic regression. The results were combined with age-specific incidence rates to estimate 5-year and lifetime absolute risks of BC across percentiles of PRS by PV status and first-degree family history of BC.

RESULTS

The estimated lifetime risks of BC among general-population noncarriers, based on 10th and 90th percentiles of PRS, were 9.1%-23.9% and 6.7%-18.2% for women with or without first-degree relatives with BC, respectively. Taking PRS into account, more than 95% of BRCA1, BRCA2, and PALB2 carriers had > 20% lifetime risks of BC, whereas, respectively, 52.5% and 69.7% of ATM and CHEK2 carriers without first-degree relatives with BC, and 78.8% and 89.9% of those with a first-degree relative with BC had > 20% risk.

CONCLUSION

PRS facilitates personalization of BC risk among carriers of PVs in predisposition genes. Incorporating PRS into BC risk estimation may help identify > 30% of CHEK2 and nearly half of ATM carriers below the 20% lifetime risk threshold, suggesting the addition of PRS may prevent overscreening and enable more personalized risk management approaches.

Genetic insights into biological mechanisms governing human ovarian ageing

Reproductive longevity is essential for fertility and influences healthy ageing in women1,2, but insights into its underlying biological mechanisms and treatments to preserve it are limited. Here we identify 290 genetic determinants of ovarian ageing, assessed using normal variation in age at natural menopause (ANM) in about 200,000 women of European ancestry. These common alleles were associated with clinical extremes of ANM; women in the top 1% of genetic susceptibility have an equivalent risk of premature ovarian insufficiency to those carrying monogenic FMR1 premutations3. The identified loci implicate a broad range of DNA damage response (DDR) processes and include loss-of-function variants in key DDR-associated genes. Integration with experimental models demonstrates that these DDR processes act across the life-course to shape the ovarian reserve and its rate of depletion. Furthermore, we demonstrate that experimental manipulation of DDR pathways highlighted by human genetics increases fertility and extends reproductive life in mice. Causal inference analyses using the identified genetic variants indicate that extending reproductive life in women improves bone health and reduces risk of type 2 diabetes, but increases the risk of hormone-sensitive cancers. These findings provide insight into the mechanisms that govern ovarian ageing, when they act, and how they might be targeted by therapeutic approaches to extend fertility and prevent disease.

Functional annotation of the 2q35 breast cancer risk locus implicates a structural variant in influencing activity of a long-range enhancer element

A combination of genetic and functional approaches has identified three independent breast cancer risk loci at 2q35. A recent fine-scale mapping analysis to refine these associations resulted in 1 (signal 1), 5 (signal 2), and 42 (signal 3) credible causal variants at these loci. We used publicly available in silico DNase I and ChIP-seq data with in vitro reporter gene and CRISPR assays to annotate signals 2 and 3. We identified putative regulatory elements that enhanced cell-type-specific transcription from the IGFBP5 promoter at both signals (30- to 40-fold increased expression by the putative regulatory element at signal 2, 2- to 3-fold by the putative regulatory element at signal 3). We further identified one of the five credible causal variants at signal 2, a 1.4 kb deletion (esv3594306), as the likely causal variant; the deletion allele of this variant was associated with an average additional increase in IGFBP5 expression of 1.3-fold (MCF-7) and 2.2-fold (T-47D). We propose a model in which the deletion allele of esv3594306 juxtaposes two transcription factor binding regions (annotated by estrogen receptor alpha ChIP-seq peaks) to generate a single extended regulatory element. This regulatory element increases cell-type-specific expression of the tumor suppressor gene IGFBP5 and, thereby, reduces risk of estrogen receptor-positive breast cancer (odds ratio = 0.77, 95% CI 0.74-0.81, p = 3.1 × 10-31).

Genome-wide homozygosity and risk of four non-Hodgkin lymphoma subtypes

AIM

Recessive genetic variation is thought to play a role in non-Hodgkin lymphoma (NHL) etiology. Runs of homozygosity (ROH), defined based on long, continuous segments of homozygous SNPs, can be used to estimate both measured and unmeasured recessive genetic variation. We sought to examine genome-wide homozygosity and NHL risk.

METHODS

We used data from eight genome-wide association studies of four common NHL subtypes: 3061 chronic lymphocytic leukemia (CLL), 3814 diffuse large B-cell lymphoma (DLBCL), 2784 follicular lymphoma (FL), and 808 marginal zone lymphoma (MZL) cases, as well as 9374 controls. We examined the effect of homozygous variation on risk by: (1) estimating the fraction of the autosome containing runs of homozygosity (FROH); (2) calculating an inbreeding coefficient derived from the correlation among uniting gametes (F3); and (3) examining specific autosomal regions containing ROH. For each, we calculated beta coefficients and standard errors using logistic regression and combined estimates across studies using random-effects meta-analysis.

RESULTS

We discovered positive associations between FROH and CLL (β = 21.1, SE = 4.41, P = 1.6 × 10-6) and FL (β = 11.4, SE = 5.82, P = 0.02) but not DLBCL (P = 1.0) or MZL (P = 0.91). For F3, we observed an association with CLL (β = 27.5, SE = 6.51, P = 2.4 × 10-5). We did not find evidence of associations with specific ROH, suggesting that the associations observed with FROH and F3 for CLL and FL risk were not driven by a single region of homozygosity.

CONCLUSION

Our findings support the role of recessive genetic variation in the etiology of CLL and FL; additional research is needed to identify the specific loci associated with NHL risk.

Toxoplasma gondii infection and the risk of adult glioma in two prospective studies

Toxoplasma gondii (T gondii) is a common parasite that shows affinity to neural tissue and may lead to the formation of cysts in the brain. Previous epidemiologic studies have suggested an association between glioma and increased prevalence of T gondii infection, but prospective studies are lacking. Therefore, we examined the association between prediagnostic T gondii antibodies and risk of glioma in two prospective cohorts using a nested case-control study design. Cases and matched controls were selected from the American Cancer Society's Cancer Prevention Study-II Nutrition Cohort (CPSII-NC) (n = 37 cases and 74 controls) and the Norwegian Cancer Registry's Janus Serum Bank (Janus) (n = 323 cases and 323 controls). Blood samples collected prior to diagnosis were analyzed for antibodies to two T gondii surface antigens (p22 and sag-1), with individuals considered seropositive if antibodies to either antigen were detected. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI) for each cohort. In both cohorts, a suggestive increase in glioma risk was observed among those infected with T gondii (OR: 2.70; 95% CI: 0.96-7.62 for CPSII-NC; OR: 1.32, 95% CI: 0.85-2.07 for Janus), particularly among participants with high antibody titers specific to the sag-1 antigen (CPSII-NC OR: 3.35, 95% CI: 0.99-11.38; Janus OR: 1.79, 95% CI: 1.02-3.14). Our findings provide the first prospective evidence of an association between T gondii infection and risk of glioma. Further studies with larger case numbers are needed to confirm a potential etiologic role for T gondii in glioma.

Gene-Environment Interactions Relevant to Estrogen and Risk of Breast Cancer: Can Gene-Environment Interactions Be Detected Only among Candidate SNPs from Genome-Wide Association Studies?

In this study we aim to examine gene-environment interactions (GxEs) between genes involved with estrogen metabolism and environmental factors related to estrogen exposure. GxE analyses were conducted with 1970 Korean breast cancer cases and 2052 controls in the case-control study, the Seoul Breast Cancer Study (SEBCS). A total of 11,555 SNPs from the 137 candidate genes were included in the GxE analyses with eight established environmental factors. A replication test was conducted by using an independent population from the Breast Cancer Association Consortium (BCAC), with 62,485 Europeans and 9047 Asians. The GxE tests were performed by using two-step methods in GxEScan software. Two interactions were found in the SEBCS. The first interaction was shown between rs13035764 of NCOA1 and age at menarche in the GE|2df model (p-2df = 1.2 × 10-3). The age at menarche before 14 years old was associated with the high risk of breast cancer, and the risk was higher when subjects had homozygous minor allele G. The second GxE was shown between rs851998 near ESR1 and height in the GE|2df model (p-2df = 1.1 × 10-4). Height taller than 160 cm was associated with a high risk of breast cancer, and the risk increased when the minor allele was added. The findings were not replicated in the BCAC. These results would suggest specificity in Koreans for breast cancer risk.

Prospective investigation of polyomavirus infection and the risk of adult glioma

Glioma is an aggressive primary tumor of the brain with a poorly understood etiology. We studied the association of 4 human polyomaviruses (HPyV)—JC virus (JCV), BK virus (BKV), human polyomavirus 6 (HPyV6), and Merkel cell polyomavirus (MCPyV) with glioma risk within the Cancer Prevention Study II in the US (CPS-II) and the Janus Serum Bank in Norway. Cohort participants subsequently diagnosed with glioma from the CPS-II (n = 37) and Janus Serum Bank (n = 323), a median of 6.9 and 15.4 years after blood collection, respectively, were matched to individual controls on age, sex, and date of blood draw. Serum antibodies to the major viral capsid protein (VP1) were used to establish infection history for each polyomavirus. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. In the Janus Serum Bank, MCPyV infection was associated with a higher risk of glioma overall (OR: 1.56; 95% CI 1.10, 2.19). A modest, nonsignificant positive association with MCPyV infection was also observed in CPS-II (OR: 1.29; 95% CI 0.54, 3.08). In both cohorts, glioma risk was not significantly related to infection with JCV, BKV or HPyV6. The present study suggests that MCPyV infection may increase glioma risk.

Prediagnostic Antibody Responses to Fusobacterium nucleatum Proteins Are Not Associated with Risk of Colorectal Cancer in a Large U.S. Consortium

BACKGROUND

The association between prediagnostic antibody responses to Fusobacterium nucleatum (F. nucleatum) and subsequent risk of colorectal cancer is not established.

METHODS

We conducted a nested case-control study of 8,126 participants in a consortium of 10 prospective cohorts in the United States.

RESULTS

Higher seroprevalence of any F. nucleatum antibody was observed among non-White participants (51.1%) compared with White participants (31.2%). We did not find any statistically significant association between seropositivity to any of the eight F. nucleatum proteins and colorectal cancer risk.

CONCLUSIONS

Prediagnostic antibody responses to F. nucleatum proteins were not associated with the risk of colorectal cancer.

IMPACT

Future studies may consider a more specific detection of the immunoglobulin isotypes or focus on examining F. nucleatum in stool or tissue samples.

Body size and weight change over adulthood and risk of breast cancer by menopausal and hormone receptor status: a pooled analysis of 20 prospective cohort studies

Associations between anthropometric factors and breast cancer (BC) risk have varied inconsistently by estrogen and/or progesterone receptor (ER/PR) status. Associations between prediagnostic anthropometric factors and risk of premenopausal and postmenopausal BC overall and ER/PR status subtypes were investigated in a pooled analysis of 20 prospective cohorts, including 36,297 BC cases among 1,061,915 women, using multivariable Cox regression analyses, controlling for reproductive factors, diet and other risk factors. We estimated dose-response relationships and tested for nonlinear associations using restricted cubic splines. Height showed positive, linear associations for premenopausal and postmenopausal BC risk (6-7% RR increase per 5 cm increment), with stronger associations for receptor-positive subtypes. Body mass index (BMI) at cohort baseline was strongly inversely associated with premenopausal BC risk, and strongly positively-and nonlinearly-associated with postmenopausal BC (especially among women who never used hormone replacement therapy). This was primarily observed for receptor-positive subtypes. Early adult BMI (at 18-20 years) showed inverse, linear associations for premenopausal and postmenopausal BC risk (21% and 11% RR decrease per 5 kg/m2, respectively) with stronger associations for receptor-negative subtypes. Adult weight gain since 18-20 years was positively associated with postmenopausal BC risk, stronger for receptor-positive subtypes, and among women who were leaner in early adulthood. Women heavier in early adulthood generally had reduced premenopausal BC risk, independent of later weight gain. Positive associations between height, baseline (adult) BMI, adult weight gain and postmenopausal BC risk were substantially stronger for hormone receptor-positive versus negative subtypes. Premenopausal BC risk was positively associated with height, but inversely with baseline BMI and weight gain (mostly in receptor-positive subtypes). Inverse associations with early adult BMI seemed stronger in receptor-negative subtypes of premenopausal and postmenopausal BC.

Erythrocyte levels of cadmium and lead and risk of B-cell non-Hodgkin lymphoma and multiple myeloma

Cadmium and lead are persistent environmental toxins that are known or probable carcinogens, based on evidence for causality for nonhematologic cancers. Associations of these metals with risk of non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) are unknown but biologically plausible. To examine the associations of circulating levels of lead and cadmium exposure with risk of B-cell NHL (B-NHL) and multiple myeloma, we conducted a nested case-control study among 299 incident B-cell NHLs and 76 MM cases within the Cancer Prevention Study-II Nutrition Cohort (CPS-II NC). Each case was incidence-density matched to two eligible controls on age, race, sex and blood draw date. Conditional logistic regression was used to estimate relative risks (RR) and 95% confidence intervals (CI) for lymphoid malignancies overall and stratified by subtype. We observed a significant positive association between high erythrocyte lead concentration and risk of lymphoid malignancies overall (RR = 1.16, 95% CI: 1.02-1.33 per 17.6 μg/L (1 standard deviation [SD])) and follicular lymphoma in particular (RR = 1.80, 95% CI: 1.15-2.80 per SD). In contrast, there was no association between erythrocyte cadmium and risk of B-NHL (RR = 0.89, 95% CI: 0.75-1.06 per 0.37 μg/L [1 SD]), or any B-NHL subtypes; but a strong inverse association with MM risk (RR = 0.59, 95% CI: 0.38-0.89, per SD). Results from our study suggest a positive association between erythrocyte lead level and risk of lymphoid malignancies and a possible inverse association between cadmium and myeloma. Additional research is needed to confirm and further explore these findings.

Sustained Weight Loss and Risk of Breast Cancer in Women 50 Years and Older: A Pooled Analysis of Prospective Data

BACKGROUND

Excess body weight is an established cause of postmenopausal breast cancer, but it is unknown if weight loss reduces risk.

METHODS

Associations between weight change and risk of breast cancer were examined among women aged 50 years and older in the Pooling Project of Prospective Studies of Diet and Cancer. In 10 cohorts, weight assessed on three surveys was used to examine weight change patterns over approximately 10 years (interval 1 median = 5.2 years; interval 2 median = 4.0 years). Sustained weight loss was defined as no less than 2 kg lost in interval 1 that was not regained in interval 2. Among 180 885 women, 6930 invasive breast cancers were identified during follow-up.

RESULTS

Compared with women with stable weight (±2 kg), women with sustained weight loss had a lower risk of breast cancer. This risk reduction was linear and specific to women not using postmenopausal hormones (>2-4.5 kg lost: hazard ratio [HR] = 0.82, 95% confidence interval [CI] = 0.70 to 0.96; >4.5-<9 kg lost: HR = 0.75, 95% CI = 0.63 to 0.90; ≥9 kg lost: HR = 0.68, 95% CI = 0.50 to 0.93). Women who lost at least 9 kg and gained back some (but not all) of it were also at a lower risk of breast cancer. Other patterns of weight loss and gain over the two intervals had a similar risk of breast cancer to women with stable weight.

CONCLUSIONS

These results suggest that sustained weight loss, even modest amounts, is associated with lower breast cancer risk for women aged 50 years and older. Breast cancer prevention may be a strong weight-loss motivator for the two-thirds of American women who are overweight or obese.

Abstract 1051: Association of Toxoplasma gondii antibodies in blood and risk of glioma

Background: Brain and other nervous system cancers are relatively rare but remain the eighth most common cancer among persons aged 40 years and older. Gliomas are the most common type of primary brain cancer, have poor overall survival, and their etiology remains unclear. Toxoplasma gondii (T. gondii) is a common protozoan parasite and has been reported to cause glioma-like tumors in animals. In humans, the infection shows affinity to neural tissue and may lead to local necrosis and inflammation, and the formation of cysts in the brain from which infection may be reactivated according to host immunologic status. Previous ecologic and case-control studies have suggested an association with increased risk of gliomas in humans infected with T. gondii, but retrospective collection of exposure information from brain tumor patients is challenging. In this study, we assessed the relation between prediagnostic T. gondii antibodies and risk of glioma in two prospective cohorts.

Methods: Cases and matched controls were selected from the American Cancer Society's Cancer Prevention Study-II (CPSII) and the Norwegian Cancer Registry's Janus Serum Bank (Janus). To avoid potential effects of preclinical disease on serum antibody titers, the study was restricted to cases with blood collected a minimum of 3 years (in CPSII) or 5 years (in Janus) prior to glioma diagnosis. Using a multiplex serological assay, blood samples were analyzed simultaneously for antibodies to two surface antigens (p22 and sag1) specific to T. gondii which represent acute parasitic infection. Samples were considered positive for T. gondii infection if either antibody was positive, defined using assay-specific cutoffs unique to each antigen. Conditional logistic regression was used to calculate odds ratios for each cohort separately.

Results: A total of 37 cases and 74 controls were included from CPSII while 323 cases and 323 controls were included from Janus. The median age at blood draw was 71 years in CPSII and 41.1 years in Janus. In both cohorts, there was a suggestive increased risk of glioma among those infected with T. gondii. The association was strongest for gliomas diagnosed in approximately the first decade after blood collection in both Janus (OR: 2.50; 95% CI: 0.97-6.44, p = 0.058) and CPSII (OR: 2.71; 95% CI: 0.95-7.62, p = 0.060), with similar results observed in high grade glioblastoma (CPSII N = 27, OR: 2.31, 95% CI: 0.71-7.47; Janus N = 61, OR: 2.25, 95% CI: 0.70-7.31) and lower grade gliomas (Janus N = 47, OR: 3.00, 95% CI: 0.61-15).

Conclusions: Blood antibody levels from two prospective cohorts indicate a possible association between T. gondii infection and increased risk of glioma. The association was strongest in the first decade after antibody measurement. The consistency, magnitude, and direction of the association support the need for pooled analyses with larger case numbers for definitive investigation.

Citation Format: James M. Hodge, Anna E. Coghill, Youngchul Kim, Noemi Bender, Stephanie Smith-Warner, Tom K. Grimsrud, Susan M. Gapstur, Tim Waterboer, Lauren R. Teras, Kathleen M. Egan. Association of Toxoplasma gondii antibodies in blood and risk of glioma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1051.

Relationship Between Muscle-Strengthening Activity and Cause-Specific Mortality in a Large US Cohort

INTRODUCTION

Muscle-strengthening activity (MSA) has beneficial effects on hypertension, glucose homeostasis, and other health conditions; however, its association with mortality is not as well understood.

METHODS

We analyzed data from the Cancer Prevention Study-II Nutrition Cohort (data collection 1982-2014), a prospective US cohort that consisted of 72,462 men and women who were free of major chronic diseases; 18,034 of the cohort died during 13 years of follow-up (2001-2014). We used Cox proportional hazards modeling, controlling for various potential confounding factors, to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for MSA (none, >0 to <1 h/wk, 1 to <2 h/wk, and ≥2 h/wk) in relation to mortality risk, independent of and in combination with aerobic physical activity.

RESULTS

The association between MSA and mortality appeared to be nonlinear (quadratic trend P value, <.001). After multivariable adjustment and comparison with no MSA, engaging in less than 2 hours per week of MSA was associated with lowered all-cause mortality (>0 to <1 h/wk: HR = 0.88, 95% CI, 0.82-0.94; 1 to <2 h/wk: HR = 0.90, 95% CI, 0.84-0.97), but engaging in 2 or more hours per week was not associated with reduced risk (HR = 1.01; 95% CI, 0.92-1.09). Associations were similar but not significant for cancer mortality. Engaging in >0 to <1 hr/wk of MSA was associated with a 19% lower risk (HR = 0.81; 95% CI, 0.71-0.92) of cardiovascular disease mortality, but more time spent in MSA was not associated with reduced risk (quadratic trend P value =.005). Associations did not vary by amount of moderate-to-vigorous aerobic physical activity.

CONCLUSION

Engaging in ≥2 hours per week of MSA was associated with lower all-cause mortality, independent of aerobic activity. Reasons for the lack of association with higher amounts of MSA are unclear. Our findings support recommending muscle-strengthening activities for overall health.

Lipid Trait Variants and the Risk of Non-Hodgkin Lymphoma Subtypes: A Mendelian Randomization Study

BACKGROUND

Lipid traits have been inconsistently linked to risk of non-Hodgkin lymphoma (NHL). We examined the association of genetically predicted lipid traits with risk of diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), and marginal zone lymphoma (MZL) using Mendelian randomization (MR) analysis.

METHODS

Genome-wide association study data from the InterLymph Consortium were available for 2,661 DLBCLs, 2,179 CLLs, 2,142 FLs, 824 MZLs, and 6,221 controls. SNPs associated (P < 5 × 10-8) with high-density lipoprotein (HDL, n = 164), low-density lipoprotein (LDL, n = 137), total cholesterol (TC, n = 161), and triglycerides (TG, n = 123) were used as instrumental variables (IV), explaining 14.6%, 27.7%, 16.8%, and 12.8% of phenotypic variation, respectively. Associations between each lipid trait and NHL subtype were calculated using the MR inverse variance-weighted method, estimating odds ratios (OR) per standard deviation and 95% confidence intervals (CI).

RESULTS

HDL was positively associated with DLBCL (OR = 1.14; 95% CI, 1.00-1.30) and MZL (OR = 1.09; 95% CI, 1.01-1.18), while TG was inversely associated with MZL risk (OR = 0.90; 95% CI, 0.83-0.99), all at nominal significance (P < 0.05). A positive trend was observed for HDL with FL risk (OR = 1.08; 95% CI, 0.99-1.19; P = 0.087). No associations were noteworthy after adjusting for multiple testing.

CONCLUSIONS

We did not find evidence of a clear or strong association of these lipid traits with the most common NHL subtypes. While these IVs have been previously linked to other cancers, our findings do not support any causal associations with these NHL subtypes.

IMPACT

Our results suggest that prior reported inverse associations of lipid traits are not likely to be causal and could represent reverse causality or confounding.

Medical conditions and physical function deficits among multiple primary cancer survivors

PURPOSE

Survivors of multiple primary cancers make up a sizable proportion of all cancer survivors, yet little is known about the health of this population. We examined the prevalence of medical conditions and physical function deficits among multiple primary survivors compared with single primary survivors and individuals without a cancer history.

METHODS

Participants were enrolled in the Cancer Prevention Study (CPS)-II Nutrition Cohort in 1992/1993. Prevalent medical conditions (diabetes, heart conditions, cerebrovascular conditions, emphysema/chronic bronchitis, osteoporosis, osteoarthritis), physical function limitations, use of a cane or walker, balance difficulties, and falls within the past year were assessed on a follow-up survey completed in 2011. We estimated age- and sex-adjusted prevalence ratios (PRs), comparing multiple primary survivors (N = 1003) to single primary survivors (N = 12,849) and participants without cancer (N = 63,578).

RESULTS

The prevalence of medical conditions did not differ substantially between multiple primary survivors and either comparison group. However, multiple primary survivors were more likely to report severe limitations in physical function than the single primary (PR = 1.48 (95% CI, 1.28-1.71)) and no-cancer (PR = 1.64 (95% CI, 1.42-1.88)) groups. Using a cane or walker and balance difficulties were also significantly more common among multiple primary survivors.

CONCLUSIONS

Despite a similar prevalence of comorbid medical conditions, severe functional limitations were significantly more common among multiple primary survivors than single primary survivors or individuals without cancer.

IMPLICATIONS FOR CANCER SURVIVORS

Assessment of functional status and treatment of physical deficits may be an especially critical component of care for older patients with a history of multiple cancer diagnoses.

Genome-wide Association Study Identifies HLA-DPB1 as a Significant Risk Factor for Severe Aplastic Anemia

Severe aplastic anemia (SAA) is a rare disorder characterized by hypoplastic bone marrow and progressive pancytopenia. The etiology of acquired SAA is not understood but is likely related to abnormal immune responses and environmental exposures. We conducted a genome-wide association study of individuals with SAA genetically matched to healthy controls in discovery (359 cases, 1,396 controls) and validation sets (175 cases, 1,059 controls). Combined analyses identified linked SNPs in distinct blocks within the major histocompatibility complex on 6p21. The top SNP encodes p.Met76Val in the P4 binding pocket of the HLA class II gene HLA-DPB1 (rs1042151A>G, odds ratio [OR] 1.75, 95% confidence interval [CI] 1.50-2.03, p = 1.94 × 10-13) and was associated with HLA-DP cell surface expression in healthy individuals (p = 2.04 × 10-6). Phylogenetic analyses indicate that Val76 is not monophyletic and likely occurs in conjunction with different HLA-DP binding groove conformations. Imputation of HLA-DPB1 alleles revealed increased risk of SAA associated with Val76-encoding alleles DPB1∗03:01, (OR 1.66, p = 1.52 × 10-7), DPB1∗10:01 (OR 2.12, p = 0.0003), and DPB1∗01:01 (OR 1.60, p = 0.0008). A second SNP near HLA-B, rs28367832G>A, reached genome-wide significance (OR 1.49, 95% CI 1.22-1.78, p = 7.27 × 10-9) in combined analyses; the association remained significant after excluding cases with clonal copy-neutral loss-of-heterozygosity affecting class I HLA genes (8.6% of cases and 0% of controls). SNPs in the HLA class II gene HLA-DPB1 and possibly class I (HLA-B) are associated with SAA. The replacement of Met76 to Val76 in certain HLA-DPB1 alleles might influence risk of SAA through mechanisms involving DP peptide binding specificity, expression, and/or other factors affecting DP function.

Genetically Determined Height and Risk of Non-hodgkin Lymphoma

Although the evidence is not consistent, epidemiologic studies have suggested that taller adult height may be associated with an increased risk of some non-Hodgkin lymphoma (NHL) subtypes. Height is largely determined by genetic factors, but how these genetic factors may contribute to NHL risk is unknown. We investigated the relationship between genetic determinants of height and NHL risk using data from eight genome-wide association studies (GWAS) comprising 10,629 NHL cases, including 3,857 diffuse large B-cell lymphoma (DLBCL), 2,847 follicular lymphoma (FL), 3,100 chronic lymphocytic leukemia (CLL), and 825 marginal zone lymphoma (MZL) cases, and 9,505 controls of European ancestry. We evaluated genetically predicted height by constructing polygenic risk scores using 833 height-associated SNPs. We used logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI) for association between genetically determined height and the risk of four NHL subtypes in each GWAS and then used fixed-effect meta-analysis to combine subtype results across studies. We found suggestive evidence between taller genetically determined height and increased CLL risk (OR = 1.08, 95% CI = 1.00-1.17, p = 0.049), which was slightly stronger among women (OR = 1.15, 95% CI: 1.01-1.31, p = 0.036). No significant associations were observed with DLBCL, FL, or MZL. Our findings suggest that there may be some shared genetic factors between CLL and height, but other endogenous or environmental factors may underlie reported epidemiologic height associations with other subtypes.

Inherited variants at 3q13.33 and 3p24.1 are associated with risk of diffuse large B-cell lymphoma and implicate immune pathways

We previously identified five single nucleotide polymorphisms (SNPs) at four susceptibility loci for diffuse large B-cell lymphoma (DLBCL) in individuals of European ancestry through a large genome-wide association study (GWAS). To further elucidate genetic susceptibility to DLBCL, we sought to validate two loci at 3q13.33 and 3p24.1 that were suggestive in the original GWAS with additional genotyping. In the meta-analysis (5662 cases and 9237 controls) of the four original GWAS discovery scans and three replication studies, the 3q13.33 locus (rs9831894; minor allele frequency [MAF] = 0.40) was associated with DLBCL risk [odds ratio (OR) = 0.83, P = 3.62 × 10-13]. rs9831894 is in linkage disequilibrium (LD) with additional variants that are part of a super-enhancer that physically interacts with promoters of CD86 and ILDR1. In the meta-analysis (5510 cases and 12 817 controls) of the four GWAS discovery scans and four replication studies, the 3p24.1 locus (rs6773363; MAF = 0.45) was also associated with DLBCL risk (OR = 1.20, P = 2.31 × 10-12). This SNP is 29 426-bp upstream of the nearest gene EOMES and in LD with additional SNPs that are part of a highly lineage-specific and tumor-acquired super-enhancer that shows long-range interaction with AZI2 promoter. These loci provide additional evidence for the role of immune function in the etiology of DLBCL, the most common lymphoma subtype.

Genetic overlap between autoimmune diseases and non-Hodgkin lymphoma subtypes

Epidemiologic studies show an increased risk of non-Hodgkin lymphoma (NHL) in patients with autoimmune disease (AD), due to a combination of shared environmental factors and/or genetic factors, or a causative cascade: chronic inflammation/antigen-stimulation in one disease leads to another. Here we assess shared genetic risk in genome-wide-association-studies (GWAS). Secondary analysis of GWAS of NHL subtypes (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, follicular lymphoma, and marginal zone lymphoma) and ADs (rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis). Shared genetic risk was assessed by (a) description of regional genetic of overlap, (b) polygenic risk score (PRS), (c)"diseasome", (d)meta-analysis. Descriptive analysis revealed few shared genetic factors between each AD and each NHL subtype. The PRS of ADs were not increased in NHL patients (nor vice versa). In the diseasome, NHLs shared more genetic etiology with ADs than solid cancers (p = .0041). A meta-analysis (combing AD with NHL) implicated genes of apoptosis and telomere length. This GWAS-based analysis four NHL subtypes and three ADs revealed few weakly-associated shared loci, explaining little total risk. This suggests common genetic variation, as assessed by GWAS in these sample sizes, may not be the primary explanation for the link between these ADs and NHLs.

Abstract 5037: Erythrocyte levels of cadmium and lead and risk of B-cell non-Hodgkin lymphoma and multiple myeloma

Heavy metals such as cadmium and lead are ubiquitous in the environment and have been classified as carcinogens by the International Agency for Research on Cancer. While research is limited, associations of heavy metals with risk of lymphoid malignancies is plausible given that other environmental factors have been associated with these cancers. To further explore associations of cadmium and lead exposure with risk of lymphoid malignancies, we conducted a nested case-control study within the Cancer Prevention Study-II (CPS-II) Nutrition cohort, a U.S. prospective cohort of men and women. Incident B-cell non-Hodgkin lymphomas (B-NHL) and multiple myelomas (MM) were identified from 32,704 CPS-II participants who were cancer-free at time of blood collection between 1998-2001. Cases included the following histologic subtypes: chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), multiple myeloma (MM), and other B-cell lymphoma. Each case was matched to two eligible controls that were selected among those who were cancer-free at the time of the case’s diagnosis. The matching factors included race, age, gender, and blood draw date. Cadmium and lead levels were measured in stored erythrocytes from the blood draw. Conditional logistic regression models were used to estimate relative risks (RR) and 95% confidence intervals (CI) for lymphoid malignancy overall and stratified by NHL subtype. The final analytic cohort consisted of 375 B-NHL or MM cases (95 DBLCL, 90 CLL/SLL, 62 FL, 76 MM, and 52 other B-cell lymphoma), and 750 matched controls. The cohort was 56% male, and an average of 69.9 years of age at the time of blood draw. There was a significant, positive association between erythrocyte levels of lead and risk of lymphoid malignancy overall (RR: 1.17, 95% CI: 1.03 - 1.33 per 1 standard deviation (SD; 17.6 µg/L) increase in lead level). This association appeared to be driven by FL (per SD of lead RR: 1.76, 95% CI: 1.21 - 2.57). No associations between lead and DLBCL, CLL/SLL, MM, or other B-cell lymphoma were observed. Results appeared similar when additionally controlling for alcohol use and smoking status. There was no association between cadmium and lymphoid malignancies overall; however, cadmium was inversely associated with risk of multiple myeloma (Q4 vs Q1 RR: 0.30, 95% CI: 0.12 - 0.75). Preliminary results from this nested case-control analysis suggests that a positive association between erythrocyte lead levels and risk of lymphoid malignancies (particularly follicular lymphoma) may exist. Reasons for an inverse association between cadmium and risk of multiple myeloma are unclear but might be due to chance. Further research is needed to fully explore and confirm these findings.

Citation Format: Emily L. Deubler, Susan M. Gapstur, W. Ryan Diver, Mia M. Gaudet, James M. Hodge, Victoria L. Stevens, Marjorie L. McCullough, Laura G. Haines, Keith E. Levine, Lauren R. Teras. Erythrocyte levels of cadmium and lead and risk of B-cell non-Hodgkin lymphoma and multiple myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5037.

Abstract 600: Clues to understanding the association between B-activation markers and the risk of B-cell non-Hodgkin lymphoma

Although severe immune dysregulation is an established risk factor for B-cell non-Hodgkin lymphoma (B-NHL), the role of subtle immune perturbations is unclear. However, associations between plasma/serum immune markers and B-NHL in immunocompetent individuals suggest a role for more moderate immune dysregulation in lymphomagenesis. To further understand the associations of immune markers with B-NHL risk, we evaluated associations between these markers and subsequent B-NHL risk; and also examined potential lymphomagens as predictors of the markers. Among the eligible population of 32,704 cancer-free individuals in the Cancer Prevention Study-II Nutrition Cohort who donated a blood sample between 1998 and 2001, 273 B-NHL cases were identified during ~13 years of follow-up. Cases were incidence-density matched to cancer-free controls on age, race, and sex. Plasma level of soluble CD23 (sCD23), sCD27, sCD30, and CXCL13 were measured by ELISA at the Institute for Risk Assessment Sciences, Utrecht University. Rate ratios (RR) and 95% confidence intervals (CI) were estimated using conditional logistic regression. Associations between infectious, lifestyle, and demographic factors and B-activation marker level were examined using multivariable linear regression. We observed strong associations for all four markers with risk of B-NHL (per standard deviation increase in the biomarker: CXCL13: Risk Ratio (RR)=4.18, 95% confidence interval (CI): 2.46-7.11; CD23: RR=3.59, 95% CI: 2.50-5.18; CD27: RR=2.04, 95% CI: 1.48-2.81; CD30: RR=3.12, 95% CI: 2.01-4.84). The associations remained strong regardless of time between biomarker measurement and B-NHL diagnosis with the exception of sCD27 which was attenuated ≥8 years after biomarker measurement. We did not observe differences by major B-NHL subtype with the exception of a notably stronger association for sCD23 with chronic lymphocytic leukemia (CLL). Age was the strongest predictor of CXCL13 (p&lt;0.0001), sCD27 (p=0.0009), and sCD30 (p=0.0043) level, but was not associated with sCD23 (p=0.1018). Body mass index, smoking, and alcohol intake were not associated with any of the markers. However, two Epstein-Barr virus reactivation markers (early antigen and ZEBRA) were associated with sCD27 (p=0.004 and p=0.003 respectively).These varied risk factor associations and time-since-biomarker measurement patterns, suggest that there may be different roles in lymphomagenesis for different B-activation markers. Understanding these associations may help identify high risk individuals—and potential targets for early intervention for B-NHL.

Citation Format: Lauren R. Teras, Mia M. Gaudet, Krishnaveni Subbiah, Esmeralda J. Krop, Roel Vermeulen, Susan M. Gapstur. Clues to understanding the association between B-activation markers and the risk of B-cell non-Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 600.

Physical Activity, Sitting Time, and Risk of Myelodysplastic Syndromes, Acute Myeloid Leukemia, and Other Myeloid Malignancies

INTRODUCTION

There is limited research on associations of moderate-to-vigorous physical activity (MVPA) and sitting with risk of myeloid neoplasms (MN) or MN subtypes. We examined these associations in the Cancer Prevention Study-II Nutrition Cohort.

METHODS

Among 109,030 cancer-free participants (mean age 69.2, SD 6.1 years) in 1999, 409 were identified as having been diagnosed with a MN [n = 155 acute myeloid leukemia (AML), n = 154 myelodysplastic syndromes (MDS), n = 100 other ML] through June 2013. Cox proportional hazards regression was used to calculate multivariable adjusted hazard ratios (HR) and 95% confidence intervals (CI) for associations of MVPA (MET-h/wk) and sitting (h/d) with risk of all MN, myeloid leukemia only, MDS, and AML.

RESULTS

Compared with insufficient MVPA [>0-<7.5 metabolic equivalent hours/week (MET)-h/wk], the HR (95% CI) for meeting physical activity guidelines (7.5-<15 MET-h/wk MVPA) and risk of MN was 0.74 (95% CI, 0.56-0.98) and for doubling guidelines (15-<22.5 MET-h/wk) was 0.75 (0.53-1.07); however, there was no statistically significant association for higher MVPA (22.5+ MET-h/wk, HR, 0.93; 95% CI, 0.73-1.20). Similarly, meeting/doubling guidelines was associated with lower risk of MDS (HR, 0.57; 95% CI, 0.35-0.92/HR, 0.51; 95% CI, 0.27-0.98), but there was no association for 22.5+ MET-h/wk (HR, 0.93; 95% CI, 0.63-1.37). MVPA was not associated with risk of myeloid leukemia or AML. Sitting time was not associated with risk of any outcome.

CONCLUSIONS

These results suggest that there may be a nonlinear association between MVPA and risk of MDS and possibly other MN.

IMPACT

Further studies are needed to better understand the dose-response relationships between MVPA and risk of MDS, a highly fatal and understudied cancer.

Anthropometric factors and risk of myeloid leukaemias and myelodysplastic syndromes: a prospective study and meta-analysis

There is insufficient evidence linking excess body weight to risk of myeloid malignancies. We investigated this association using data from the Cancer Prevention Study-II (CPS-II), and a meta-analysis of published cohort studies. Among 152 090 CPS-II participants, 387 acute myeloid leukaemias (AML), 100 chronic myeloid leukaemias (CML) and 170 MDS were identified over 21 years of follow-up. In CPS-II, body mass index (BMI) was weakly associated with risk of CML (hazard ratio [HR] = 1·04, 95% confidence interval [CI]: 0·99-1·09 per 1 unit increase in BMI), AML (HR = 1·01, 95% CI: 0·98-1·03) and MDS (HR = 1·03, 95% CI: 0·99-1·07). After controlling for other anthropometric factors, no clear association was observed for height, BMI at age 18 years or weight change. In the meta-analysis (n = 7117 myeloid leukaemias), BMI 25-29·9 kg/m² (HR_pooled  = 1·36, 95% CI: 1·12-1·59) and BMI ≥30 kg/m² (HR_pooled  = 1·43, 95% CI: 1·18-1·69) were associated with higher risk of myeloid leukaemia overall, compared to a BMI <25 kg/m² . Likewise, BMI ≥25 kg/m² was positively associated with both AML and CML risk individually in the meta-analysis. These results underscore the need for large studies to detect associations with rare cancers, and show a modest, but positive association between excess body weight and myeloid malignancy risk.