Racial Differences in Vaginal Fluid Metabolites and Association with Systemic Inflammation Markers among Ovarian Cancer Patients: A Pilot Study

The vaginal microbiome differs by race and contributes to inflammation by directly producing or consuming metabolites or by indirectly inducing host immune response, but its potential contributions to ovarian cancer (OC) disparities remain unclear. In this exploratory cross-sectional study, we examine whether vaginal fluid metabolites differ by race among patients with OC, if they are associated with systemic inflammation, and if such associations differ by race. Study participants were recruited from the Ovarian Cancer Epidemiology, Healthcare Access, and Disparities Study between March 2021 and September 2022. Our study included 36 study participants with ovarian cancer who provided biospecimens; 20 randomly selected White patients and all 16 eligible Black patients, aged 50-70 years. Acylcarnitines (n = 45 species), sphingomyelins (n = 34), and ceramides (n = 21) were assayed on cervicovaginal fluid, while four cytokines (IL-1β, IL-10, TNF-α, and IL-6) were assayed on saliva. Seven metabolites showed >2-fold differences, two showed significant differences using the Wilcoxon rank-sum test (p < 0.05; False Discovery Rate > 0.05), and 30 metabolites had coefficients > ±0.1 in a Penalized Discriminant Analysis that achieved two distinct clusters by race. Arachidonoylcarnitine, the carnitine adduct of arachidonic acid, appeared to be consistently different by race. Thirty-eight vaginal fluid metabolites were significantly correlated with systemic inflammation biomarkers, irrespective of race. These findings suggest that vaginal fluid metabolites may differ by race, are linked with systemic inflammation, and hint at a potential role for mitochondrial dysfunction and sphingolipid metabolism in OC disparities. Larger studies are needed to verify these findings and further establish specific biological mechanisms that may link the vaginal microbiome with OC racial disparities.

Association of reproductive risk factors and breast cancer molecular subtypes: a systematic review and meta-analysis

BACKGROUND

Associations between reproductive factors and breast cancer (BC) risk vary by molecular subtype (i.e., luminal A, luminal B, HER2, and triple negative/basal-like [TNBC]). In this systematic review and meta-analysis, we summarized the associations between reproductive factors and BC subtypes.

METHODS

Studies from 2000 to 2021 were included if BC subtype was examined in relation to one of 11 reproductive risk factors: age at menarche, age at menopause, age at first birth, menopausal status, parity, breastfeeding, oral contraceptive (OC) use, hormone replacement therapy (HRT), pregnancy, years since last birth and abortion. For each reproductive risk factor, BC subtype, and study design (case-control/cohort or case-case), random-effects models were used to estimate pooled relative risks and 95% confidence intervals.

RESULTS

A total of 75 studies met the inclusion criteria for systematic review. Among the case-control/cohort studies, later age at menarche and breastfeeding were consistently associated with decreased risk of BC across all subtypes, while later age at menopause, later age of first childbirth, and nulliparity/low parity were associated with increased risk of luminal A, luminal B, and HER2 subtypes. In the case-only analysis, compared to luminal A, postmenopausal status increased the risk of HER2 and TNBC. Associations were less consistent across subtypes for OC and HRT use.

CONCLUSION

Identifying common risk factors across BC subtypes can enhance the tailoring of prevention strategies, and risk stratification models can benefit from subtype specificity. Adding breastfeeding status to current BC risk prediction models can enhance predictive ability, given the consistency of the associations across subtypes.

Associations of Healthcare Affordability, Availability, and Accessibility with Quality Treatment Metrics in Patients with Ovarian Cancer

BACKGROUND

Differential access to quality care is associated with racial disparities in ovarian cancer survival. Few studies have examined the association of multiple healthcare access (HCA) dimensions with racial disparities in quality treatment metrics, that is, primary debulking surgery performed by a gynecologic oncologist and initiation of guideline-recommended systemic therapy.

METHODS

We analyzed data for patients with ovarian cancer diagnosed from 2008 to 2015 in the Surveillance, Epidemiology, and End Results-Medicare database. We defined HCA dimensions as affordability, availability, and accessibility. Modified Poisson regressions with sandwich error estimation were used to estimate the relative risk (RR) for quality treatment.

RESULTS

The study cohort was 7% NH-Black, 6% Hispanic, and 87% NH-White. Overall, 29% of patients received surgery and 68% initiated systemic therapy. After adjusting for clinical variables, NH-Black patients were less likely to receive surgery [RR, 0.83; 95% confidence interval (CI), 0.70-0.98]; the observed association was attenuated after adjusting for healthcare affordability, accessibility, and availability (RR, 0.91; 95% CI, 0.77-1.08). Dual enrollment in Medicaid and Medicare compared with Medicare only was associated with lower likelihood of receiving surgery (RR, 0.86; 95% CI, 0.76-0.97) and systemic therapy (RR, 0.94; 95% CI, 0.92-0.97). Receiving treatment at a facility in the highest quartile of ovarian cancer surgical volume was associated with higher likelihood of surgery (RR, 1.12; 95% CI, 1.04-1.21).

CONCLUSIONS

Racial differences were observed in ovarian cancer treatment quality and were partly explained by multiple HCA dimensions.

IMPACT

Strategies to mitigate racial disparities in ovarian cancer treatment quality must focus on multiple HCA dimensions. Additional dimensions, acceptability and accommodation, may also be key to addressing disparities.

Association of lipid profile biomarkers with breast cancer by molecular subtype: analysis of the MEND study

There is conflicting evidence on the role of lipid biomarkers in breast cancer (BC), and no study to our knowledge has examined this association among African women. We estimated odds ratios (ORs) and 95% confidence intervals (95% CI) for the association of lipid biomarkers-total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides-with odds of BC overall and by subtype (Luminal A, Luminal B, HER2-enriched and triple-negative or TNBC) for 296 newly diagnosed BC cases and 116 healthy controls in Nigeria. Each unit standard deviation (SD) increase in triglycerides was associated with 39% increased odds of BC in fully adjusted models (aOR: 1.39; 95% CI: 1.03, 1.86). Among post-menopausal women, higher total cholesterol (aOR: 1.65; 95% CI: 1.06, 2.57), LDL cholesterol (aOR: 1.59; 95% CI: 1.04, 2.41), and triglycerides (aOR: 1.91; 95% CI: 1.21, 3.01) were associated with increased odds of BC. Additionally, each unit SD increase in LDL was associated with 64% increased odds of Luminal B BC (aOR 1.64; 95% CI: 1.06, 2.55). Clinically low HDL was associated with 2.7 times increased odds of TNBC (aOR 2.67; 95% CI: 1.10, 6.49). Among post-menopausal women, higher LDL cholesterol and triglycerides were significantly associated with increased odds of Luminal B BC and HER2 BC, respectively. In conclusion, low HDL and high LDL are associated with increased odds of TN and Luminal B BC, respectively, among African women. Future prospective studies can definitively characterize this association and inform clinical approaches targeting HDL as a BC prevention strategy.

Abstract PO-113: Overall survival in ovarian cancer patients seeking care at more than one treatment facility

Purpose: Ovarian cancer is the most lethal gynecological cancer and despite advances in treatment, most patients are diagnosed at an advanced stage with poor prognosis. Black women have a lower 5 year survival than White women when diagnosed at the same stage, and while there are a number of contributing factors, quality of treatment center may play a significant role. Choice in treatment facility may be limited by insurance coverage, availability of high-volume hospitals or specialists, or ability to access high-quality facilities, and it is unclear how a change in treatment facility may impact ovarian cancer survival. Methods: Participant usage files from the National Cancer Database were used to interrogate the characteristics of patients that seek treatment at more than one Commission on Cancer accredited facility in the United States to determine the effect on overall survival. Multivariable Cox regression analysis models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CI) to determine risk of mortality for patients receiving all of their first course treatment at one facility vs those receiving first course treatment at more than one facility. The fully-adjusted model was then stratified by race/ethnicity (Non-Hispanic White, Non-Hispanic Black, Hispanic) and by facility type (Community, Comprehensive Community, Academic/Research, Integrative Network). Results: A total of 211,937 women were included in the analysis. Patients were more likely to receive all of their first course treatment at one facility (81%). Patents treated at more than one facility had a 26% increase in ovarian cancer mortality compared with those treated at a single facility (HR: 1.26, 95% CI: 1.24-1.28). When stratified by race, NH-Black patients had the lowest increase in overall survival (HR: 1.08, 95% CI: 1.03-1.14) when compared with NH-White (HR: 1.27, 95% CI: 1.25-1.29) and Hispanic (HR: 1.33, 95% CI: 1.28-1.39) patients. Stratification by facility type showed that among women receiving treatment at more than one facility, those switching to an academic research center had the highest mortality (HR: 1.31, 95% CI: 1.28-1.34). Conclusions: Ovarian cancer patients that received treatment at more than one facility had a higher rate of mortality than those who were treated at a single center. Our findings suggest the need for further investigation into the effects of continuity of care, including how race, facility type, and other socioeconomic factors may modulate those effects.

Citation Format: April Deveaux, Jessica Islam, Tomi Akinyemiju. Overall survival in ovarian cancer patients seeking care at more than one treatment facility [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-113.

Metabolic Syndrome and Risk of Breast Cancer by Molecular Subtype: Analysis of the MEND Study

Metabolic syndrome is a cluster of biological irregularities that is a known risk factor for cardiovascular disease, stroke, and diabetes. In a case-control study of 555 West African women, we observed that metabolic syndrome was strongly associated with breast cancer and the aggressive triple-negative molecular subtype, highlighting a need for clinical and lifestyle interventions targeting metabolic syndrome to reduce breast cancer risk in this population.

Ovarian Cancer Epidemiology, Healthcare Access and Disparities (ORCHiD): methodology for a population-based study of black, Hispanic and white patients with ovarian cancer

INTRODUCTION

Less than 40% of patients with ovarian cancer (OC) in the USA receive stage-appropriate guideline-adherent surgery and chemotherapy. Black patients with cancer report greater depression, pain and fatigue than white patients. Lack of access to healthcare likely contributes to low treatment rates and racial differences in outcomes. The Ovarian Cancer Epidemiology, Healthcare Access and Disparities study aims to characterise healthcare access (HCA) across five specific dimensions-Availability, Affordability, Accessibility, Accommodation and Acceptability-among black, Hispanic and white patients with OC, evaluate the impact of HCA on quality of treatment, supportive care and survival, and explore biological mechanisms that may contribute to OC disparities.

METHODS AND ANALYSIS

We will use the Surveillance Epidemiology and Ends Results dataset linked with Medicare claims data from 9744 patients with OC ages 65 years and older. We will recruit 1641 patients with OC (413 black, 299 Hispanic and 929 white) from cancer registries in nine US states. We will examine HCA dimensions in relation to three main outcomes: (1) receipt of quality, guideline adherent initial treatment and supportive care, (2) quality of life based on patient-reported outcomes and (3) survival. We will obtain saliva and vaginal microbiome samples to examine prognostic biomarkers. We will use hierarchical regression models to estimate the impact of HCA dimensions across patient, neighbourhood, provider and hospital levels, with random effects to account for clustering. Multilevel structural equation models will estimate the total, direct and indirect effects of race on treatment mediated through HCA dimensions.

ETHICS AND DISSEMINATION

Result dissemination will occur through presentations at national meetings and in collaboration with collaborators, community partners and colleagues across othercancer centres. We will disclose findings to key stakeholders, including scientists, providers and community members. This study has been approved by the Duke Institutional Review Board (Pro00101872). Safety considerations include protection of patient privacy. All disseminated data will be deidentified and summarised.

Association of body composition with odds of breast cancer by molecular subtype: analysis of the Mechanisms for Established and Novel Risk Factors for Breast Cancer in Nigerian Women (MEND) study

BACKGROUND

The association between obesity and breast cancer (BC) has been extensively studied among US, European and Asian study populations, with often conflicting evidence. However, despite the increasing prevalence of obesity and associated conditions in Africa, the continent with the highest age-standardized BC mortality rate globally, few studies have evaluated this association, and none has examined in relation to molecular subtypes among African women. The current analysis examines the association between body composition, defined by body mass index (BMI), height, and weight, and BC by molecular subtype among African women.

METHODS

We estimated odds ratios (ORs) and 95% confidence intervals (95% CI) for the association between measures of body composition and BC and molecular subtypes among 419 histologically confirmed cases of BC and 286 healthy controls from the Mechanisms for Established and Novel Risk Factors for Breast Cancer in Women of Nigerian Descent (MEND) case-control study.

RESULTS

Higher BMI (aOR: 0.79; 95% CI: 0.67, 0.95) and weight (aOR: 0.83; 95% CI: 0.69, 0.98) were associated with reduced odds of BC in adjusted models, while height was associated with non-statistically significant increased odds of BC (aOR: 1.07, 95% CI: 0.90, 1.28). In pre/peri-menopausal, but not post-menopausal women, both higher BMI and weight were significantly associated with reduced odds of BC. Further, higher BMI was associated with reduced odds of Luminal A, Luminal B, and HER2-enriched BC among pre/peri-menopausal women, and reduced odds of triple-negative BC among post-menopausal women.

CONCLUSIONS

Higher BMI and weight were associated with reduced odds of BC overall and by molecular subtype among West African women. Larger studies of women of African descent are needed to definitively characterize these associations and inform cancer prevention strategies.

Association of high-sensitivity C-reactive protein and odds of breast cancer by molecular subtype: analysis of the MEND study

Breast cancer (BC) in Nigeria is characterized by disproportionately aggressive molecular subtypes. C-reactive protein (CRP) is associated with risk and aggressiveness for several types of cancer. We examined the association of high-sensitivity CRP (hsCRP) with odds of BC by molecular subtype among Nigerian women. Among 296 newly diagnosed BC cases and 259 healthy controls, multivariable logistic regression models were used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) for the association between hsCRP and odds of BC overall and by molecular subtype (luminal A, luminal B, HER2-enriched and triple-negative or TNBC). High hsCRP (> 3 mg/L) was observed in 57% of cases and 31% of controls and was associated with 4 times the odds of BC (aOR: 4.43; 95% CI: 2.56, 7.66) after adjusting for socio-demographic, reproductive, and clinical variables. This association persisted regardless of menopausal status and body mass index (BMI) category. High hsCRP was associated with increased odds of TNBC (aOR: 3.32; 95% CI: 1.07, 10.35), luminal A BC (aOR: 4.03; 95% CI: 1.29, 12.64), and HER2-enriched BC (aOR: 6.27; 95% CI: 1.69, 23.25). Future studies are necessary in this population to further evaluate a potential role for CRP as a predictive biomarker for BC.

Racial disparities in palliative care utilization among metastatic gynecological cancer patients living at last follow-up: An analysis of the National Cancer Data Base

The National Comprehensive Cancer Network recommends palliative care should be integrated in to cancer care starting from cancer diagnosis. However, traditionally palliative care is prioritized for cancer patients at the end-of-life. In our main article titled “Racial and Ethnic Disparities in Palliative Care Utilization Among Gynecological Cancer Patients” we present data describing racial/ethnic disparities among metastatic gynecological cancer patients who were deceased at last follow-up. Here, we expand our population to evaluate racial disparities in palliative care utilization among (1) all metastatic gynecologic cancer patients, regardless of vital status (alive or deceased) (n = 176,899) and (2) among only patients who were alive at last follow-up (n = 66,781). We used data from the 2016 National Cancer Database (NCDB) and included patients between ages 18–90 years with metastatic (stage III-IV) gynecologic cancers including, ovarian, cervical and uterine cancer. Palliative care was defined by NCDB as non-curative treatment, and could include surgery, radiation, chemotherapy, and pain management or any combination. We used multivariable logistic regression to evaluate racial disparities in palliative care use among our two populations of interest. Overall, the mean age of gynecologic cancer patients utilizing palliative care was 66 years. Five percent of all metastatic gynecologic oncology patients utilized palliative care overall; and by cancer site palliative care use was as follows: 4% among ovarian, 9% among cervical, and 11% among uterine cancer patients. Among patients who utilized palliative care, 62% utilized surgery, radiation or chemotherapy only and 12% utilized pain management as a form of palliative care. Among ovarian cancer patients, Hispanic ovarian cancer patients were less likely to utilize palliative care compared to their NH-White counterparts (aOR: 0.79, 95% CI: 0.68–0.91). Among cervical cancer patients, we observed that Hispanic (aOR: 0.65, 95% CI: 0.56–0.75) and Asian (aOR: 0.74, 95% CI: 0.59–0.93) were less likely to utilize palliative care than NH-White cervical cancer patients. We observed no racial disparities in palliative care utilization among uterine cancer patients. When we focused on patients who were alive at last follow-up we found that only 3% of patients utilized palliative care. We also conducted multivariable analyses of racial/ethnic disparities among ovarian and cervical cancer patients who were alive at last follow-up. We were unable to conduct multivariable analyses of uterine cancer patients who were alive at last follow-up due to limited sample size of those who utilized palliative care. We observed no racial/ethnic disparities among this patient population of metastatic gynecologic patients.

Abstract B59: Race-related differential splicing of the insulin receptor: A novel target underlying prostate cancer disparities

Background: Age-adjusted incidence and mortality rates for prostate cancer (PCa) among African American (AA) men are significantly greater than among white men. Much of this disparity remains after controlling for behavioral, social, and neighborhood determinants of health, which is consistent with a biologic contribution. Evidence suggests that the genetic etiology and molecular progression of PCa are different in AAs versus whites. Our laboratory has identified novel alternatively spliced genes in AA versus white PCa biopsy tissue that track with population-based prostate tumor aggressiveness. This work addresses the urgent need to interrogate novel molecular mechanisms driving more aggressive PCa in AAs to aid in development of new biomarkers and therapeutic targets for improved prognosis and treatment of aggressive disease.

Methods: We have analyzed RNA from human PCa biopsy tissue from 20 AA and 15 white patients using exon arrays. From these data, we prioritized targets for further study by identifying those associated with androgen signaling and PCa and those that have also been shown to be alternatively spliced in breast, lung, and liver cancer. To validate race-related alternative splicing of the insulin receptor (INSR) gene, we have used qPCR and targeted sequencing of RNA from population-specific PCa cell lines and patient-derived explants. In addition, we have knocked down the INSR splice variants in population-specific PCa cell lines using isoform-specific siRNAs and assessed resulting alterations in proliferation using a WST-1 proliferation assay. Current studies include assessing additional resulting alterations in expression of selected key targets in INSR signaling using Western blot analysis. In addition, studies are under way to treat population-specific PCa cell lines with INSR signaling inhibitors and assess resulting alterations in PCa cell biology.

Results: Exon array analysis of RNA from AA and white PCa biopsy tissue revealed 934 differentially expressed exons in 861 corresponding genes. Thirty-nine targets have been prioritized for further study. We have validated race-related alternative splicing of INSR, involving differential exon inclusion/skipping of exon 11, in population-specific PCa cell lines and patient-derived explants, with the exclusion of exon 11 occurring more often in preclinical models of white PCa. Knockdown of INSR splice variants in population-specific PCa cell lines has shown that decreased expression of the isoform excluding exon 11 inhibits proliferation while decreased expression of the isoform including exon 11 has no effect on proliferation. Further studies to assess additional resulting alterations in expression of selected key targets in INSR signaling are under way. In addition, studies are under way to treat population-specific PCa cell lines with INSR signaling inhibitors and assess resulting alterations in PCa cell biology.

Conclusions: These studies identify differential splicing of INSR in AA and white PCa and the INSR isoform excluding exon 11 as contributors to prostate tumor aggressiveness. Further interrogation of this mechanism underlying PCa disparities and its effect on targeted therapeutics has the potential to reduce PCa disparities for AA men and improve outcomes for men of all races with aggressive disease driven by this mechanism.

Citation Format: April Deveaux, Bi-Dar Wang, Bonnie Lacroix, Brendon Patierno, Dadong Zhang, Kouros Owzar, Norman Lee, Daniel George, Jennifer Freedman, Steven Patierno. Race-related differential splicing of the insulin receptor: A novel target underlying prostate cancer disparities [abstract]. In: Proceedings of the Tenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2017 Sep 25-28; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2018;27(7 Suppl):Abstract nr B59.

The gastrointestinal microbiota and colorectal cancer

The human gut is home to a complex and diverse microbiota that contributes to the overall homeostasis of the host. Increasingly, the intestinal microbiota is recognized as an important player in human illness such as colorectal cancer (CRC), inflammatory bowel diseases, and obesity. CRC in itself is one of the major causes of cancer mortality in the Western world. The mechanisms by which bacteria contribute to CRC are complex and not fully understood, but increasing evidence suggests a link between the intestinal microbiota and CRC as well as diet and inflammation, which are believed to play a role in carcinogenesis. It is thought that the gut microbiota interact with dietary factors to promote chronic inflammation and CRC through direct influence on host cell physiology, cellular homeostasis, energy regulation, and/or metabolism of xenobiotics. This review provides an overview on the role of commensal gut microbiota in the development of human CRC and explores its association with diet and inflammation.

Azithromycin analogue CSY0073 attenuates lung inflammation induced by LPS challenge

BACKGROUND AND PURPOSE

Azithromycin is a macrolide antibiotic with anti-inflammatory and immunomodulating effects. Long-term azithromycin therapy in patients with chronic lung diseases such as cystic fibrosis has been associated with increased antimicrobial resistance, emergence of hypermutable strains, ototoxicity and cardiac toxicity. The aim of this study was to assess the anti-inflammatory effects of the non-antibiotic azithromycin derivative CSY0073.

EXPERIMENTAL APPROACH

We compared the effects of CSY0073 with those of azithromycin in experiments on bacterial cultures, Pseudomonas aeruginosa biofilm, lung cells and mice challenged intranasally with P. aeruginosa LPS.

KEY RESULTS

In contrast to azithromycin, CSY0073 did not inhibit the growth of P. aeruginosa, Staphylococcus aureus or Haemophilus influenzae and had no effect on an established P. aeruginosa biofilm. Bronchoalveolar lavage (BAL) fluids and lung homogenates collected after the LPS challenge in mice showed that CSY0073 and azithromycin (200 mg·kg(-1), i.p.) decreased neutrophil counts at 24 h and TNF-α, CXCL1 and CXCL2 levels in the BAL fluid after 3 h and IL-6, CXCL2 and IL-1β levels in the lung after 3 h compared with the vehicle. However, only azithromycin reduced IL-1β levels in the lung 24 h post LPS challenge. CSY0073 and azithromycin similarly diminished the production of pro-inflammatory cytokines by macrophages, but not lung epithelial cells, exposed to P. aeruginosa LPS.

CONCLUSIONS AND IMPLICATIONS

Unlike azithromycin, CSY0073 had no antibacterial effects but it did have a similar anti-inflammatory profile to that of azithromycin. Hence, CSY0073 may have potential as a long-term treatment for patients with chronic lung diseases.