Abstract 1997: Health-related quality of life at diagnosis in survivors of adolescent and young adult cancer

Purpose: Data are lacking on the distribution, factors associated with, and long-term impact of diminished health-related quality of life (HRQoL) at diagnosis in adolescent and young adult (AYA) cancer survivors (≥2 years post cancer diagnosis). Our goal was to fill this gap in knowledge.

Methods: A cohort of AYA (15y - 39y) cancer patients treated at MD Anderson between 2000-2016 who had survived at least 2 y was identified from our Institutional Tumor Registry. HRQoL was assessed at diagnosis with the SF12v1 questionnaire. Demographic and behavioral risk factors, tumor type, and vital status were ascertained. Physical composite summary (PCS) and mental composite summary (MCS) scores were generated from SF12 responses following mean-based normalization; PCS or MCS < 50 indicated “poor” HRQoL. Statistical tests included ANOVA, quantile regression, and multivariable Cox proportional hazards.

Results: 2,609 AYA cancer survivors (75% diagnosed between age of 26-39 y; 67% White, 18% Hispanic and 9% Black) were included. Breast cancer was the most frequent diagnosis (25%), followed by sarcoma (12%) and Hodgkin lymphoma (10%). Median follow-up for participants was 10.5 y. Overall mean PCS and MCS scores at diagnosis were 45.3 (SD: 11.4) and 47.0 (SD: 10.5), respectively. Female AYA cancer patients had significantly higher PCS, yet lower MCS compared to their male counterparts (both P<0.001). A positive association between age at diagnosis and PCS was observed (P<0.001), in contrast to the inverse association with MCS (P<0.001). Differences in PCS (P<0.001) and MCS (P=0.001) were also evident by tumor type. For example, women with breast cancer reported the most favorable PCS (51.5) at diagnosis, yet among the lowest MCS (46.1) of the nine tumor types analyzed. The Black AYA population had a larger burden of poor PCS at diagnosis with 61% of patients reporting scores <50 compared to 55% of Hispanic and 51% of non-Hispanic whites. Significant predictors of diminished PCS in AYA cancer survivors in the bottom 25% of PCS scores were younger age at diagnosis (P=0.003), male gender (P<0.001), diagnosis of a hematologic malignancy versus solid tumor (P<0.001), smoking (P=0.003) and not consuming any alcohol currently (P<0.001). Overall, low PCS (<50) at diagnosis (HR=1.57, P<0.001), and diagnosis of a solid tumor compared to a hematologic malignancy (HR=2.33, P<0.001) were associated with lower survival.

Conclusions: In this large, diverse AYA cancer survivor cohort, physical and mental HRQoL at diagnosis were impacted by AYA’s age at diagnosis, gender, tumor type, and smoking status. Low PCS at diagnosis was an independent predictor of diminished survival among AYA cancer survivors ≥2y post diagnosis. Our findings suggest that patient-reported poor physical well-being at diagnosis is a biomarker of poor prognosis for AYA cancers. Further studies are needed to identify interventions to improve outcomes for this population.

Citation Format: Goldy C. George, Clark R. Andersen, Xiaohui Tang, John A. Livingston, Michael E. Roth, Michelle A. Hildebrandt. Health-related quality of life at diagnosis in survivors of adolescent and young adult cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1997.

Abstract 826: Large-scale genome-wide association study identifies multiple novel germline susceptibility variants associated with bladder cancer risk

Background: Genomic regions that confer susceptibility for bladder cancer have provided important insights into the mechanisms of this disease. Sixteen genomic regions harboring bladder cancer susceptibility loci have been reported to date. To identify additional loci associated with bladder cancer risk, we conducted a meta-analysis including data from previously published genome-wide association studies as well as unpublished data.

Methods: Data from 32 studies including 13,790 bladder cancer cases and 343,502 controls of European ancestry were included. Stratified analyses by sex and smoking status, as well as heterogeneity in risk by muscle-invasiveness, were also conducted. We tested for multiplicative and additive interactions between cigarette smoking and susceptibility loci that achieved genome-wide significance. After genotyping, quality control, and imputation log-additive effects were calculated by study/array group using regression models adjusting for age and significant eigenvectors. Results were combined by meta-analysis using a fixed-effects model.

Results: We report strengthened or independent signals in several previously published regions at 4p16.3 (TACC3, FGFR3), 5p15.33 (CLPTM1L, TERT) and 11p15.5 (TNNT3, LSP1), as well as nine novel loci. In addition, we observed the first evidence of effect modification by sex at the FGFR3 locus, with a stronger risk observed in women (pmultiplicative-interaction=0.002). Further, we confirmed an interaction between smoking and a susceptibility locus at 8p22 (NAT2), indicating an increased risk of bladder cancer among smokers with the NAT2 slow acetylation genotype/phenotype (pmultiplicative-interaction=0.001). We also identified additional multiplicative, as well as additive, interactions between several novel loci and cigarette smoking status. In addition, we are currently building a risk stratification model using the combined effects of smoking and genetic susceptibility to identify subgroups of individuals at higher and lower absolute risk of bladder cancer.

Conclusions: This meta-analysis identified 3 novel loci in previously reported regions and 9 novel bladder cancer susceptibility loci in new regions. These results add to our knowledge of the genetic architecture of bladder cancer. In addition, observed gene-smoking interactions suggest that risk stratification models may have translational implications, informing future disease screening efforts.

Citation Format: Stella Koutros, Lambertus A. Kiemeney, Roger L. Milne, Yuanqing Ye, Vijai Joseph, Jonine Figueroa, Nilanjan Chatterjee, Graham G. Giles, Michelle A. Hildebrandt, Lars Dyrskjot, Kenneth Offit, Manolis Kogevinas, Elisabete Weiderpass, Marjorie L. McCullough, Neal D. Freedman, Demetrius Albanes, Charles Kooperberg, Victoria Cortessis, Margaret R. Karagas, Dalsu Baris, Alison Johnson, Molly R. Schwenn, Helena Furberg, Dean F. Bajorin, Parichoy Pal Choudhury, Oscar Florez-Vargas, Olivier Cussenot, Geraldine Cancel-Tassin, Simone Benhamou, Peter Kraft, Stefano Porru, Mark P. Purdue, Katherine A. McGlynn, Cari M. Kitahara, Christopher A. Haiman, Mark H. Greene, Thorunn Rafnar, Stephen J. Chanock, Xifeng Wu, Francisco X. Real, Debra T. Silverman, Montserrat Garcia-Closas, Kari Stefansson, Ludmila Prokunina-Olsson, Nuria Malats, Nathaniel Rothman. Large-scale genome-wide association study identifies multiple novel germline susceptibility variants associated with bladder cancer risk [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 826.

Abstract 853: GPX4 Gene Expression is Dose-responsive to Doxorubicin Exposure in iPSC-Cardiomyocytes and Correlated With Mitochondrial Function

Impaired mitochondrial function has been implicated as a mechanism of doxorubicin-induced cardiotoxicity, however the precise genes that regulate this process in human cardiomyocytes remain to be elucidated. We hypothesized that doxorubicin significantly alters expression of genes involved in mitochondrial function in human cardiomyocytes, which in turn impairs mitochondrial respiration. Towards this, we treated human inducible pluripotent stem cell (iPSC)-cardiomyocytes with doxorubicin at 15 different time and dose conditions. Gene expression was assessed by RNAseq for each condition and 169 genes involved in mitochondrial function were analyzed for differential expression between control and treated conditions. Mitochondrial respiration (basal respiration, ATP production, maximal respiration, and spare respiratory capacity) was measured using the Seahorse Bioscience XFe96 Cell Mito Stress Test kit and correlated to gene expression levels. Of the 169 genes analyzed, 25 were significantly differentially expressed (P < 0.05) including GPX4 (P = 5.70 x 10 -3 ). Expression of GPX4 remained significant in pairwise comparisons by dose for day 2 and qRT-PCR validation confirmed a dose-dependent decrease in GPX4 expression. Maximal respiration (r = -0.62; P = 0.031) and spare respiratory capacity (r = -0.67; P = 0.017) correlated with GPX4 expression in doxorubicin-treated iPSC-cardiomyocytes. GPX4 encodes a glutathione peroxidase that is responsible for protecting the cell against oxidative damage. Damage due to reactive oxygen species (ROS) is one of the established mechanisms of anthracycline-induced cardiac damage. Our findings underscore a role for mitochondrial function and ROS in the development of doxorubicin-induced cardiotoxicity and implicates GPX4 in this process. The assessment of doxorubicin-altered gene expression in iPSC-cardiomyocytes may provide insight into how impaired mitochondrial respiration leads to cardiotoxicity and heart failure in cancer survivors treated with doxorubicin and other anthracyclines.

Abstract 2686: Associations between a polygenic risk score and risk of multiple myeloma and its precursor

Genome-wide association studies (GWAS) conducted among populations of European ancestry (EA) have identified 23 common single nucleotide polymorphisms (SNPs) associated with multiple myeloma (MM) risk. We hypothesize that the combination of these SNPs in a polygenic risk score (PRS) is likely to be a strong risk factor for MM. However, it is unclear whether the genetic variation associated with MM susceptibility also predisposes to monoclonal gammopathy of undetermined significance (MGUS). Thus, we calculated a PRS and evaluated the association with risk of MM and its precursor, MGUS.

We pooled genotype data for 2434 MM and 3446 controls from ten MM GWAS of individuals of EA within the Interlymph Consortium, for 23 MM risk SNPs identified by prior GWAS. An additional 754 MGUS cases were ascertained from Mayo Clinic and MD Anderson clinical practices. To calculate the PRS, we used the risk estimates corresponding to the 23 SNP associations from the largest published MM GWAS. The log of the odds ratio (OR) for each SNP was multiplied by the respective number of risk alleles and summed to generate a PRS for each individual. The PRS was examined continuously, per one standard deviation (SD), and as quintiles, based on the PRS distribution in the controls. Associations of PRS with MM and MGUS risk were examined separately, using multivariable logistic regression assuming an additive model to assess ORs and 95% confidence intervals adjusted for age, sex, and site. We also evaluated age and sex stratified models.

The distribution of sex within MM cases, MGUS cases and controls were each ~60% male and ~40% female. The median age was 61, 66, and 66 years for MM cases, MGUS cases and controls, respectively. PRS ranged from 1.52-4.91, with a median PRS of 3.21 for MM cases, 3.19 for MGUS cases, and 3.05 for controls. PRS was significantly associated with MM risk when assessed continuously (OR=1.19 per SD, p=2.2x10-16) and categorically; compared with the middle quintile (Q3), individuals in the highest quintile (Q5) had a 66% increased MM risk (OR=1.66, p=2.3x10-9) and those in the lowest quintile (Q1) had a 38% decreased MM risk (OR=0.62, p=1.3x10-6). PRS was also significantly associated with MGUS risk (OR=1.19 per SD, p=1.7x10-11); individuals with the highest PRS (Q5) had a 77% increased risk (OR=1.77, p=4.0x10-4) and those with lowest PRS (Q1) had 30% decreased risk (OR=0.70, p=0.04), compared with Q3. When stratified by age and sex, similar associations and trends were found.

Using an independent sample of MM / MGUS cases and controls, we showed that a PRS constructed from 23 common genetic variants for MM risk is associated with risk of both MM and MGUS, regardless of age or sex. A future direction of this work is testing associations with PRS and clinical characteristics of the MM cases, as well as differences between MGUS cases that progress and those that do not. Our results suggest that common genetic variation may predispose to MGUS as the precursor to MM.

Citation Format: Alyssa I. Clay-Gilmour, Michelle A. Hildebrandt, Nicola J. Camp, Elad Ziv, Elizabeth E. Brown, Jonathan N. Hofmann, John J. Spinelli, Graham G. Giles, Parveen Bhatti, Wendy Cozen, Xifeng Wu, Dennis P. Robinson, Aaron D. Norman, Jason P. Sinnwell, Shaji K. Kumar, S Vincent Rajkumar, Susan L. Slager, Celine M. Vachon. Associations between a polygenic risk score and risk of multiple myeloma and its precursor [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 2686.

Genetic Data from Nearly 63,000 Women of European Descent Predicts DNA Methylation Biomarkers and Epithelial Ovarian Cancer Risk

DNA methylation is instrumental for gene regulation. Global changes in the epigenetic landscape have been recognized as a hallmark of cancer. However, the role of DNA methylation in epithelial ovarian cancer (EOC) remains unclear. In this study, high-density genetic and DNA methylation data in white blood cells from the Framingham Heart Study (N = 1,595) were used to build genetic models to predict DNA methylation levels. These prediction models were then applied to the summary statistics of a genome-wide association study (GWAS) of ovarian cancer including 22,406 EOC cases and 40,941 controls to investigate genetically predicted DNA methylation levels in association with EOC risk. Among 62,938 CpG sites investigated, genetically predicted methylation levels at 89 CpG were significantly associated with EOC risk at a Bonferroni-corrected threshold of P < 7.94 × 10-7. Of them, 87 were located at GWAS-identified EOC susceptibility regions and two resided in a genomic region not previously reported to be associated with EOC risk. Integrative analyses of genetic, methylation, and gene expression data identified consistent directions of associations across 12 CpG, five genes, and EOC risk, suggesting that methylation at these 12 CpG may influence EOC risk by regulating expression of these five genes, namely MAPT, HOXB3, ABHD8, ARHGAP27, and SKAP1. We identified novel DNA methylation markers associated with EOC risk and propose that methylation at multiple CpG may affect EOC risk via regulation of gene expression. SIGNIFICANCE: Identification of novel DNA methylation markers associated with EOC risk suggests that methylation at multiple CpG may affect EOC risk through regulation of gene expression.

Abstract 3011: Determinants and prognostic value of quality of life in patients with pancreatic ductal adenocarcinoma

Background Quality of life (QOL) is impaired in pancreatic cancer patients. Our aim was to investigate the determinants and prognostic value of QOL after diagnosis in a hospital-based cohort of racially/ethnically diverse patients with pancreatic ductal adenocarcinoma (PDAC). Patients and methods QOL was prospectively assessed using the Short Form-12 version 1 in 2478 PDAC patients. The Physical Component Summary (PCS) and Mental Component Summary (MCS) were categorized into tertiles based on their distribution. Ordered logistic regression was adopted to compare the risk of having lower PCS and MCS by patient sociodemographic and clinical characteristics. The association of PCS and MCS with mortality was assessed by Cox regression. Results Compared with non-Hispanic whites, Hispanics were at significantly higher risk of having lower PCS (odds ratio [95%CI], 1.69 [1.26-2.26]; P &lt; .001) and lower MCS (1.66 [1.24-2.23]; P &lt; .001). Patients diagnosed with stage III (1.80 [1.10-2.94]; P = .02) and stage IV (2.32 [1.50-3.59]; P &lt; .001) were more likely to have lower PCS than were patients diagnosed with stage I. Other determinants included sex, age, drinking, smoking, education level, and comorbidities. The low tertile of PCS (hazard ratio [95%CI], 1.94 [1.72-2.18]; P &lt; .001) and MCS (1.42 [1.26-1.59]; P &lt; .001) were each related to poor prognosis. Similar results were found for non-Hispanic Whites as compared to African Americans/Hispanics/others. Conclusion QOL after diagnosis is a significant prognostic indicator for patients with PDAC, and multiple factors determine QOL, suggesting possible means of intervention to improve QOL and outcomes of PDAC patients.

Citation Format: Yang Deng, Huakang Tu, Jeanne A. Pierzynski, Ethan Miller, Maosheng Huang, Xiangjun Gu, David W. Chang, Yuanqing Ye, Michelle A. Hildebrandt, Alison P. Klein, Scott M. Lippman, Xifeng Wu. Determinants and prognostic value of quality of life in patients with pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3011.

Abstract 892: Doxorubicin-induced cardiotoxicity in iPSC-cardiomyocytes: Altered mitochondrial gene expression and function

Introduction: Cardiomyocytes are highly vulnerable to anthracycline-induced toxicity, which may lead to heart failure. This includes doxorubicin, which is a commonly used chemotherapeutic agent. Although mitochondrial function has been implicated as a mechanism of anthracycline-induced toxicity in rodent heart cells, the precise genes that regulate this response in humans remain to be elucidated. We hypothesized that doxorubicin significantly alters expression of mitochondrial genes in human cardiomyocytes, which impairs mitochondrial function.

Methods: Human inducible pluripotent stem cell (iPSC)-derived cardiomyocytes were treated with doxorubicin or left untreated for control to assess changes in gene expression using RNAseq. A total of 169 genes involved in mitochondrial function, as defined by Ingenuity Pathway Analysis and KEGG, were analyzed for significant differences between untreated and treated conditions using DESeq2 and GenePattern 2.0. Mitochondrial respiration was measured in control and doxorubicin-treated cells using the Seahorse Bioscience XFe96 Cell Mito Stress Test kit. We used a Spearman's partial correlation coefficient analysis to correlate gene expression levels with mitochondrial basal respiration, ATP production, maximal respiration, and spare respiratory capacity for untreated and doxorubicin-treated iPSC-cardiomyocytes.

Results: Of the 169 mitochondrial genes analyzed, we identified 25 genes that were significant in our global differential expression analysis across all conditions (P&lt;0.05). Seven of these genes (ATP5D, COX5A, CYC1, HSD17B10, NDUFB10, NDUFS8, UQCRC1) remained significant in pairwise analyses between control and doxorubicin treated cells. We observed a decrease in mitochondrial respiration following treatment with doxorubicin. Maximal respiration (r=-0.929; P=0.022) and spare respiratory capacity (r=-0.98;P=0.0025) negatively correlated with NDUFS8 expression in doxorubicin-treated iPSC-cardiomyocytes.

Conclusion: Our findings underscore a role for mitochondrial function in the development of doxorubicin-induced cardiotoxicity and implicate specific genes in this process. Doxorubicin-altered gene expression in cardiomyocytes may provide insight into how impaired mitochondrial function leads to heart failure in cancer survivors.

Citation Format: Monica E. Reyes, Rashida Callender, Jianzhong Ma, Megan L. Grove, Alanna C. Morrison, Michelle A. Hildebrandt. Doxorubicin-induced cardiotoxicity in iPSC-cardiomyocytes: Altered mitochondrial gene expression and function [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 892.

MicroRNA-related genetic variants in iron regulatory genes, dietary iron intake, microRNAs and lung cancer risk

Background

Genetic variations in MicroRNA (miRNA) binding sites may alter structural accessibility of miRNA binding sites to modulate risk of cancer. This large-scale integrative multistage study was aimed to evaluate the interplay of genetic variations in miRNA binding sites of iron regulatory pathway, dietary iron intake and lung cancer (LC) risk.

Patients and methods

The interplay of genetic variant, dietary iron intake and LC risk was assessed in large-scale case-control study. Functional characterization of the validated SNP and analysis of target miRNAs were performed.

Results

We found that the miRNA binding site SNP rs1062980 in 3' UTR of Iron-Responsive Element Binding protein 2 gene (IREB2) was associated with a 14% reduced LC risk (P value = 4.9×10 - 9). Comparing to AA genotype, GG genotype was associated with a 27% reduced LC risk. This association was evident in males and ever-smokers but not in females and never-smokers. Higher level of dietary iron intake was significantly associated with 39% reduced LC risk (P value = 2.0×10 - 8). This association was only present in individuals with AG + AA genotypes with a 46% reduced risk (P value = 1.0×10 - 10), but not in GG genotype. The eQTL-analysis showed that rs1062980 significantly alters IREB2 expression level. Rs1062980 is predicted to alter a miR-29 binding site on IREB2 and indeed the expression of miR-29 is inversely correlated with IREB2 expression. Further, we found that higher circulating miR-29a level was significantly associated with 78% increased LC risk.

Conclusion

The miRNA binding site SNP rs1062980 in iron regulatory pathway, which may alter the expression of IREB2 potentially through modulating the binding of miR-29a, together with dietary iron intake may modify risk of LC both individually and jointly. These discoveries reveal novel pathway for understanding lung cancer tumorigenesis and risk stratification.

Abstract 3707: Baseline quality of life and genetic determinants and the impact on five-year lung cancer survival

Patient-reported health-related quality of life (QOL) is an important part of a cancer patient's treatment plan and has been linked to overall cancer survival. We aimed to identify the impact of QOL and potential genetic factors on five-year lung cancer survival using a lung cancer patient cohort from MD Anderson Cancer Center. QOL data was obtained from the SF-12 questionnaire. Patient responses were used to calculate Physical Component Summary (PCS) and Mental Component Summary (MCS) scores, with a lower score indicating a worse QOL. Mean baseline QOL scores were calculated for demographic factors in 7,135 patients, and individuals with a college degree (PCS = 42.0, compared to less than a high school degree PCS = 35.1, P&lt;0.0001), current alcohol drinkers (PCS = 42.0, compared to never drinkers PCS = 37.3, P&lt;0.0001), and those with no significant medical history (PCS = 40.8, compared to a significant history PCS = 38.4, P&lt;0.0001) reported an improved PCS. Individuals greater than 70 years old (MCS = 47.8, compared to those less than 50 MCS = 45.2, P&lt;0.0001), with a college degree (MCS = 48.0, compared to less than a high school degree MCS = 45.2, P&lt;0.0001), Asian Pacific Islanders (MCS = 48.5, compared to whites MCS = 46.3, P = 0.033), and current alcohol drinkers (MCS = 47.4, compared to never drinkers MCS = 45.9, P&lt;0.0001) reported a better MCS. We then analyzed the association between baseline QOL and lung cancer survival using survival data obtained from MD Anderson Tumor Registry. A PCS or MCS score less than 50 was associated with an increased risk of five-year mortality (HR = 1.20, 95% CI: 1.08-1.33, P = 0.001; HR = 1.13, 95%CI: 1.03-1.24, P = 0.008, respectively) and there was a significant difference between median survival time (MST) (PCS≥50 MST = 30.42 months, PCS&lt;50 MST = 20.70 months, Plog-rank&lt;0.0001) (MCS≥50 MST = 26.12 months, MCS&lt;50 MST = 20.17 months, Plog-rank&lt;0.0001). Finally, using a subset of the study population (N = 588), we completed a preliminary analysis of 218 single nucleotide polymorphisms (SNPs) in the p38 MAPK signaling pathway, activated in response to cellular and environmental stress, as a potential genetic determinant of QOL and five-year lung cancer survival. Using a score of 50 as the cut-off, twenty-five SNPs were associated with PCS, twenty-three SNPs were associated with MCS, and 28 SNPs were associated with five-year lung cancer survival (P&lt;0.05). Individuals with at least one variant allele of rs2715815 in MAP2K6 showed a decreased risk of poor PCS and MCS score (OR = 0.49, 95% CI = 0.26-0.90, P = 0.022; OR = 0.41, 95% CI = 0.22-0.76, P = 0.005, respectively). At least one variant allele of FASLG: rs5030772 was associated with a decreased risk of poor MCS score (OR = 0.51, 95% CI = 0.27-0.96, P = 0.038) and a decreased risk of lung cancer death (HR = 0.68, 95% CI = 0.46-1.00, P = 0.049). These findings suggest that baseline QOL in lung cancer patients as well as genetic determinants may impact lung cancer survival.

Citation Format: Jeanne A. Pierzynski, Michelle A. Hildebrandt, Yuanqing Ye, Jack A. Roth, Xifeng Wu. Baseline quality of life and genetic determinants and the impact on five-year lung cancer survival. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3707. doi:10.1158/1538-7445.AM2015-3707

Abstract 3056: Mitochondrial DNA copy number and risk of second primary tumors in long-term breast cancer survivors

Background. Mitochondria is constantly exposed to reactive oxygen species (ROS), an important factor in carcinogenesis. Altered mitochondrial DNA (mtDNA) copy number in peripheral blood has been associated with increased risks of several cancers, including breast cancer. However, the association of mtDNA copy number with clinical outcomes of breast cancer has not been reported. This study aimed to assess the association of mtDNA copy number with second primary tumors (SPT) in long-term breast cancer survivors.

Methods. We measured mtDNA by quantitative PCR in patients in 68 long-term breast cancer survivors with SPT, 100 long-term breast cancer survivors without SPT and 97 newly diagnosed breast cancer cases. Cases with and without SPT were matched by years since diagnosis, age at time of sample collection and race. Differences between mtDNA copy number among groups were analyzed using the Wilcoxon rank sum test.

Results. MtDNA copy number was significantly higher in long-term breast cancer survivors (either with SPT or not SPT) compared with newly diagnosed breast cancer patients (Mean (SD), 1.03 ± 0.25 vs 0.95 ± 0.27; p = 0.005). We did not observe significant differences of mtDNA copy number between long-term survivors with SPT and without SPT. However, in stratified analyses by epidemiological and clinical variables, we observed lower mtDNA copy number in HER2-positive long-term survivors with SPT than those without SPT (0.84 ± 0.13 vs 1.27 ± 0.44; p = 0.010) and in pre-menopause long-term survivors with SPT than those without SPT (0.95 ± 0.20 vs 1.06 ± 0.22; p = 0.034). A borderline significance of mtDNA copy number between SPT and non-SPT ER-negative long-term survivors was also noted (0.90 ± 0.17 vs 1.18 ± 0.41, p = 0.056).

Conclusion. Higher mtDNA copy number was found in long-term breast cancer survivors compared to newly diagnosed cases. There were significant associations between lower mtDNA copy number and SPT in long-term breast cancer survivors who are HER2+ or are pre-menopause. These results indicate a role of mtDNA copy number in long-term breast cancer survivorship.

Citation Format: Miguel Santibanez, Alma Rodriguez, Michelle A. Hildebrandt, David W. Chang, Xifeng Wu. Mitochondrial DNA copy number and risk of second primary tumors in long-term breast cancer survivors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3056. doi:10.1158/1538-7445.AM2015-3056

Genetic Variants in the Wnt/β-Catenin Signaling Pathway as Indicators of Bladder Cancer Risk

PURPOSE

Genetic factors that influence bladder cancer risk remain largely unknown. Previous research has suggested that there is a strong genetic component underlying the risk of bladder cancer. The Wnt/β-catenin signaling pathway is a key modulator of cellular proliferation through its regulation of stem cell homeostasis. Furthermore, variants in the Wnt/β-catenin signaling pathway have been implicated in the development of other cancers, leading us to believe that this pathway may have a vital role in bladder cancer development.

MATERIALS AND METHODS

A total of 230 single nucleotide polymorphisms in 40 genes in the Wnt/β-catenin signaling pathway were genotyped in 803 bladder cancer cases and 803 healthy controls.

RESULTS

A total of 20 single nucleotide polymorphisms were nominally significant for risk. Individuals with 2 variants of LRP6: rs10743980 were associated with a decreased risk of bladder cancer in the recessive model in the initial analysis (OR 0.76, 95% CI 0.58-0.99, p=0.039). This was validated using the bladder genome-wide association study chip (OR 0.51, 95% CI 0.27-1.00, p=0.049 and for combined analysis p=0.007).

CONCLUSIONS

Together these findings implicate variants in the Wnt/β-catenin stem cell pathway as having a role in bladder cancer etiology.

Genetic polymorphisms in MicroRNA-related genes as predictors of clinical outcomes in colorectal adenocarcinoma patients

PURPOSE

To evaluate the effects of single-nucleotide polymorphisms (SNP) in microRNA-related genes on clinical outcomes in patients with colorectal cancer (CRC) receiving first-line fluoropyrimidine-based chemotherapy.

EXPERIMENTAL DESIGN

Forty-one SNPs in 26 microRNA-related genes were genotyped in 1,097 patients with CRC recruited at the University of Texas MD Anderson Cancer Center (Houston, TX). Patients were enrolled between 1990 and 2008 and last follow-up was in 2010. The associations between genotypes and recurrence-free survival (RFS), progression-free survival (PFS), and overall survival (OS) stratified by clinical stage were analyzed in 741 newly diagnosed patients (diagnosed within 1 year) and replicated the findings in an additional 356 patients.

RESULTS

In patients with stage III disease, mir608: rs4919510 was associated with increased risk for both recurrence [HR, 2.72; 95% confidence interval (CI), 1.38-5.33] and death (HR, 3.53; 95%CI, 1.42-8.73). The associations were confirmed in the replication set, and the combined HRs for training and replication sets were 1.65 (95% CI, 1.13-2.41) for recurrence and 1.96 (95% CI, 1.19-3.21) for death, respectively. The mir219-1:rs213210 showed consistent association with death in the training set (HR, 3.86; 95% CI, 1.33-11.22), the replication set (HR, 3.33; 95% CI, 1.39-7.98), and combined data set (HR, 3.22; 95% CI, 1.70-6.10). In combined analysis of these two SNPs, patients carrying the variant genotypes at both sites exhibited a 5.6-fold increased risk of death.

CONCLUSION

Genetic polymorphisms in the microRNA pathway may predict prognosis in patients with stage III CRC treated with fluoropyrimidine-based chemotherapy.

A genome-wide association study identifies a novel susceptibility locus for renal cell carcinoma on 12p11.23

Renal cell carcinoma (RCC) is the most lethal urologic cancer. Only two common susceptibility loci for RCC have been confirmed to date. To identify additional RCC common susceptibility loci, we conducted an independent genome-wide association study (GWAS). We analyzed 533 191 single nucleotide polymorphisms (SNPs) for association with RCC in 894 cases and 1516 controls of European descent recruited from MD Anderson Cancer Center in the primary scan, and validated the top 500 SNPs in silico in 3772 cases and 8505 controls of European descent involved in the only published GWAS of RCC. We identified two common variants in linkage disequilibrium, rs718314 and rs1049380 (r(2) = 0.64, D ' = 0.84), in the inositol 1,4,5-triphosphate receptor, type 2 (ITPR2) gene on 12p11.23 as novel susceptibility loci for RCC (P = 8.89 × 10(-10) and P = 6.07 × 10(-9), respectively, in meta-analysis) with an allelic odds ratio of 1.19 [95% confidence interval (CI): 1.13-1.26] for rs718314 and 1.18 (95% CI: 1.12-1.25) for rs1049380. It has been recently identified that rs718314 in ITPR2 is associated with waist-hip ratio (WHR) phenotype. To our knowledge, this is the first genetic locus associated with both cancer risk and WHR.

Comprehensive pathway-based interrogation of genetic variations in the nucleotide excision DNA repair pathway and risk of bladder cancer

BACKGROUND

Growing evidence suggests that single nucleotide polymorphisms (SNPs) in nucleotide excision repair (NER) pathway genes play an important role in bladder cancer etiology. However, only a limited number of genes and variations in this pathway have been evaluated to date.

METHODS

In this study, the authors applied a comprehensive pathway-based approach to assess the effects of 207 tagging and potentially functional SNPs in 26 NER genes on bladder cancer risk using a large case-control study that included 803 bladder cancer cases and 803 controls.

RESULTS

In total, 17 SNPs were associated significantly with altered bladder cancer risk (P < .05), of which, 7 SNPs retained noteworthiness after they were assessed with a Bayesian approach for the probability of false discovery. The most noteworthy SNP was reference SNP 11132186 (rs11132186) in the inhibitor of growth family, member 2 (ING2) gene. Compared with the major allele-containing genotypes, the odds ratio was 0.52 (95% confidence interval, 0.32-0.83; P = .005) for the homozygous variant genotype. Three additional ING2 variants also exhibited significant associations with bladder cancer risk. Significant gene-smoking interactions were observed for 3 of the top 17 SNPs. Furthermore, through an exploratory classification and regression tree (CART) analysis, potential gene-gene interactions were identified.

CONCLUSIONS

In this a large association study of the NER pathway and the risk of bladder cancer, several novel predisposition variants were identified along with potential gene-gene and gene-environment interactions in modulating bladder cancer risk. The results reinforce the importance of a comprehensive, pathway-focused, and tagging SNP-based candidate gene approach to identify low-penetrance cancer susceptibility loci.

Abstract 4662: Genetic predictors of clinical outcomes for patients with non-small cell lung cancer

Background: Emerging evidence has shown that genetic factors can interact with host factors to influence patient's clinical outcomes. Inflammatory biomarkers have been identified as prognostic factors independent of tumor stage. To test the hypothesis that genetic variants in inflammation-related genes may modulate clinical outcome in non-small cell lung cancer (NSCLC) patients, we conducted a three-stage study, including an initial discovery phase and two validation phases. Methods: In the discovery phase, we analyzed the association between 19,458 SNPs in inflammation-related genes and SNPs from GWAS risk analysis, and clinical outcomes in 1,408 NSCLC patients. In the validation phases, the significant SNPs (p&lt;0.05) were first validated in an additional 1,104 NSCLC patients from MD Anderson and then validated in 978 NSCLC patients from Harvard University. Meta-analysis was used to summarize the combined effect of each SNP in all three stages. Results: A total of 16 SNPs were identified as top candidate predictors of respective outcomes after showing consistent associations in all three stages. Among them, 5 SNPs were associated with overall survival in the entire populations. The most significant SNP is located on chromosome 6 (discovery: HR=1.49, 95%CI=1.10-2.01, P=0.010; combined validation: HR=1.45, 95%CI=1.17-1.78, P=0.001; all combined: HR=1.46, 95% CI=1.23-1.73, P=1.59×10-5). Five SNPs were associated with overall survival in late stage unresectable patients receiving chemotherapy. The most significant SNP, located on chromosome 13, consistently showed increased risk of death in all three phases (discovery: HR=1.40, 95%CI=1.09-1.81, P=0.010; combined validation: HR=1.36, 95%CI=1.14-1.63, P=0.001; all combined: HR=1.37, 95% CI=1.19-1.59, P=2.26×10-5). Six SNPs were consistently associated with progression in early stage patient receiving surgery only. The top SNP was on chromosome 1 with protective effect against developing progression in all three phases (discovery: HR=0.52, 95%CI=0.32-0.86, P=0.033; combined validation: HR=0.63, 95%CI=0.49-0.82, P=0.001; all combined: HR=0.62, 95% CI=0.5-0.79, P=5.47×10-5). To our knowledge, this is the first study to systematically evaluate the association of genetic variations in major inflammation genes and NSCLC patients’ clinical outcomes with a multi-stage design using two of the largest lung studies in the US. Our study provides evidence that genetic variations in inflammation genes may affect clinical outcomes in NSCLC patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4662. doi:10.1158/1538-7445.AM2011-4662

Abstract 4663: Genetic variation in the p38 signaling pathway as markers for postoperative pulmonary complications in lung cancer patients

Surgical resection is the primary treatment for patients with localized non-small cell lung cancer (NSCLC). Although often a successful treatment option, a portion of these individuals will experience postoperative pulmonary complications, such as pneumonia, acute respiratory distress syndrome, and atelectasis. These complications are difficult to predict and often characterized by a hyper-inflammatory response. The p38 signaling pathway is activated following stress stimuli and in response to inflammatory signals. Because of this important role, we hypothesized that genetic polymorphisms within the core components of this pathway may result in dysregulated response to inflammation following surgery causing unforeseen complications. Therefore, in this study we genotyped 242 common, germline genetic variants from 19 p38 pathway genes in 275 Caucasian NSCLC patients who underwent a lobectomy at MD Anderson. After controlling for clinical risk factors, twenty-three significant associations with any pulmonary complication were observed (P&lt;0.05). Patients carrying at least one variant allele of IRAK2:rs778044 had a complication rate of 49.7% compared to 28.6% for patients with the common genotype for a highly significant 3.10-fold increase in risk (95% Confidence Interval [CI]: 1.76-5.47, P=9.6×10-5). A dose-response effect was evident between number of risk genotypes and risk of complication (P=2.08×10-7). Patients with the highest number of risk genotypes were nearly 14 times more likely to develop a pulmonary complication (95% CI: 5.30-36.87, P=9.73×10-8) compared to those with the fewest risk genotypes. Potential gene-gene interactions were also observed between IRAK2, MYD88, and IL1R1 that identified distinct risk groupings. Patients carrying both the variant genotypes for IRAK2:rs778044 and MYD88:rs11783456 were at highest risk, while those with the common genotype for IRAK2:rs778044 and the protective variant genotype for IL1R1:rs2287047 had the lowest risk. The increase in risk was 23.57-fold for high risk individuals compared to those with the low risk genetic profile (95% CI: 2.75-201.96, P=0.0039). These results strongly implicate the p38 pathway in modulating risk of pulmonary complications following lobectomy for NSCLC. Together with clinical and epidemiological variables, these variants may be useful biomarkers to better identify patients at high risk prior to surgery.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4663. doi:10.1158/1538-7445.AM2011-4663