Leveraging the transcriptome to further our understanding of GWAS findings: eQTLs associated with genes related to LDL and LDL subclasses, in a cohort of African Americans

Background: GWAS discoveries often pose a significant challenge in terms of understanding their underlying mechanisms. Further research, such as an integration with expression quantitative trait locus (eQTL) analyses, are required to decipher the mechanisms connecting GWAS variants to phenotypes. An eQTL analysis was conducted on genes associated with low-density lipoprotein (LDL) cholesterol and its subclasses, with the aim of pinpointing genetic variants previously implicated in GWAS studies focused on lipid-related traits. Notably, the study cohort consisted of African Americans, a population characterized by a heightened prevalence of hypercholesterolemia. Methods: A comprehensive differential expression (DE) analysis was undertaken, with a dataset of 17,948 protein-coding mRNA transcripts extracted from the whole-blood transcriptomes of 416 samples to identify mRNA transcripts associated with LDL, with further granularity delineated between small LDL and large LDL subclasses. Subsequently, eQTL analysis was conducted with a subset of 242 samples for which whole-genome sequencing data were available to identify single-nucleotide polymorphisms (SNPs) associated with the LDL-related mRNA transcripts. Lastly, plausible functional connections were established between the identified eQTLs and genetic variants reported in the GWAS catalogue. Results: DE analysis revealed 1,048, 284, and 94 mRNA transcripts that exhibited differential expression in response to LDL, small LDL, and large LDL, respectively. The eQTL analysis identified a total of 9,950 significant SNP-mRNA associations involving 6,955 SNPs including a subset 101 SNPs previously documented in GWAS of LDL and LDL-related traits. Conclusion: Through comprehensive differential expression analysis, we identified numerous mRNA transcripts responsive to LDL, small LDL, and large LDL. Subsequent eQTL analysis revealed a rich landscape of eQTL-mRNA associations, including a subset of eQTL reported in GWAS studies of LDL and related traits. The study serves as a testament to the important role of integrative genomics in unraveling the enigmatic GWAS relationships between genetic variants and the complex fabric of human traits and diseases.

Genomic, epigenomic, and transcriptomic signatures of prostate cancer between African American and European American patients

Prostate cancer is the second most common cancer in men in the United States, and racial disparities are greatly observed in the disease. Specifically, African American (AA) patients have 60% higher incidence and mortality rates, in addition to higher grade and stage prostate tumors, than European American (EA) patients. In order to narrow the gap between clinical outcomes for these two populations, genetic and molecular signatures contributing to this disparity have been characterized. Over the past decade, profiles of prostate tumor samples from different ethnic groups have been developed using molecular and functional assays coupled with next generation sequencing or microarrays. Comparative genome-wide analyses of genomic, epigenomic, and transcriptomic profiles from prostate tumor samples have uncovered potential race-specific mutations, copy number alterations, DNA methylation, and gene expression patterns. In this study, we reviewed over 20 published studies that examined the aforementioned molecular contributions to racial disparities in AA and EA prostate cancer patients. The reviewed genomic studies revealed mutations, deletions, amplifications, duplications, or fusion genes differentially enriched in AA patients relative to EA patients. Commonly reported genomic alterations included mutations or copy number alterations of FOXA1, KMT2D, SPOP, MYC, PTEN, TP53, ZFHX3, and the TMPRSS2-ERG fusion. The reviewed epigenomic studies identified that CpG sites near the promoters of PMEPA1, RARB, SNRPN, and TIMP3 genes were differentially methylated between AA and EA patients. Lastly, the reviewed transcriptomic studies identified genes (e.g. CCL4, CHRM3, CRYBB2, CXCR4, GALR1, GSTM3, SPINK1) and signaling pathways dysregulated between AA and EA patients. The most frequently found dysregulated pathways were involved in immune and inflammatory responses and neuroactive ligand signaling. Overall, we observed that the genomic, epigenomic, and transcriptomic alterations evaluated between AA and EA prostate cancer patients varied between studies, highlighting the impact of using different methods and sample sizes. The reported genomic, epigenomic, and transcriptomic alterations do not only uncover molecular mechanisms of tumorigenesis but also provide researchers and clinicians valuable resources to identify novel biomarkers and treatment modalities to improve the disparity of clinical outcomes between AA and EA patients.

Utilizing Social Media Advertisements and Participant Social Networks to Recruit African American Breast Cancer Survivors: Design and Rationale

Purpose

Our objective is to pilot an advertisement-driven sampling procedure among African American (AA) breast cancer survivors living in Maryland. These pilot study methods will inform a future population-based study of AA breast cancer survivors at high risk of poor outcomes due to biological differences and social inequities.

Methods

This cross-sectional study utilizes an innovative, social media-based advertisement campaign with an associated social media study page to recruit 100 AA breast cancer survivors. Participants are biologically female, aged 18 and older, identify as AA/Black, have a diagnosis of breast cancer, and reside in Maryland. A preset "Audience" was created via Meta (formerly Facebook) to automatically target potential interest in the online study via geolocation and public social media interests (estimated range = 101,000 women). Eligible participants complete an online survey including demographic and clinical characteristics, cancer screening, healthcare access, and utilization, COVID-19 impact, quality of doctor-patient communication, and preferences for future study participation.

Results

Recruitment began on 5 January 2022 and remains ongoing. As of 7 June 2002: 124 completed the screener, 110/124 (88.7%) consented passively, 24/110 (21.8%) started but did not complete survey, 86/110 (78.1%) completed the survey.

Conclusions

Results from this study will inform a statewide multilevel prospective population-based study to improve health behaviors, disease management, and self-efficacy of chronic disease management among AA breast cancer survivors.

Lifetime Trauma Exposure and Posttraumatic Stress Disorder Among African Americans and Black Caribbeans by Sex and Ethnicity

OBJECTIVE

Posttraumatic stress disorder (PTSD) is a debilitating disorder requiring timely diagnosis and treatment, with special attention needed for Black populations in the U.S. Yet, stakeholders often fail to recognize Black communities' heterogeneous ethnic composition, thus not allowing diverse sociocultural realities to inform PTSD interventions. This study aims to characterize sex and ethnic differences in lifetime trauma exposure, lifetime PTSD diagnosis and symptoms, and help-seeking among the African Americans and Black Caribbeans in the U.S.

METHOD

This study relied on data from the National Survey of American Life 2001-2003 (NSAL) to investigate the lifetime exposure to traumatic events and prevalence of a clinical PTSD diagnosis based on the DSM-IV among African American (n = 3,570) and Black Caribbean (n = 1,623) adults. 44.5% of respondents were men and 55.5% were women. Logistic regression was utilized to investigate the impact of traumatic events on PTSD.

RESULTS

Several ethnic and sex differences in exposure to potentially traumatic events were identified. African American respondents were more likely to experience spousal abuse and toxin exposure than their Black Caribbean counterparts. Black Caribbeans reported higher lifetime exposure to muggings, natural disasters, harsh parental discipline, being a civilian living in terror and/or being a refugee than African American respondents. Specific to sex, Black men reported more events of combat, a peacekeeper/relief worker, being mugged, toxin exposure, seeing atrocities, and/or injuring someone. Black women were more likely to have been rape/sexual assault and/or intimate partner violence victims. The assaultive violence trauma type was most predictive of lifetime PTSD diagnosis among Black Americans. African American women were more likely to report PTSD symptoms than men, with almost no significant differences in Black Caribbean men and women. Approximately half of Black Americans sought help for their worst traumatic event, commonly engaging family/friends, psychiatrists, and mental health professionals. Further, there were almost no ethnic and sex differences related to professional and non-professional help sought.

CONCLUSION

Future PTSD-related research should aim to characterize the heterogenous experiences of potentially traumatic events within different Black communities. Clinicians working with Black clients should strive to understand the limitations within their tools/interventions in meeting the needs of diverse groups.

The Impact of COVID-19 on Risky Behaviors and Health Changes in African-American Smokers Who Are Eligible for LDCT Screening

The COVID-19 pandemic has disrupted much of day-to-day life in the US and around the world. Smokers have a higher risk of adverse outcomes due to COVID-19. This study investigated the impact of COVID-19 on risky behaviors and health changes in lower income African-American smokers eligible for Low dose computed tomography (LDCT) screening, who may be more adversely impacted by the COVID-19 pandemic. A total of 22 African-American daily smokers who were eligible for LDCT screening participated in this study. The mean age of participants was 61.2 years old (SD = 4.7), 77.3% of the smokers were female, all participants had an income below $20,000, and 63.6% were on Medicaid. Descriptive statistics were used to provide summary information on demographics, COVID-19, and health status. Results showed that participants increased cigarette smoking, spent more time on screens, increased sugary drink consumption, consumed more vegetables and fruits, and engaged in more gardening activities during the COVID-19 pandemic. However, participants also decreased physical activity time and slept less during the pandemic. In general, more than one-third of participants gained more body weight and reported increased stress and anxiety. Our results suggest that African-American smokers who qualify for LDCT screening should be encouraged to consider strategies not only for smoking cessation, but also risky behavior control and management.

The association of prostatic lipids with progression, racial disparity and discovery of biomarkers in prostate cancer

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This study performed lipid profiling on human PCa and BPT tissues matched with patient's age and race, pathological grades and clinical stages.

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The human prostatic lipid profiles were widely associated with the pathogenesis, progression and racial disparity of PCa.

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Neutral lipids had greater impact on pathogenesis, progression and racial disparity of PCa as compared to phospholipids. Cholesteryl ester is the only lipid class significantly higher in PCa than in BPT in all population and stratified AA and CA populations.

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A panel of prostatic lipid parameters in each study population were identified as diagnostic and prognostic biomarkers with high sensitivity, specificity and accuracy simultaneously.

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Lipid profiling on mouse prostatic tissue from mouse PCa model further confirmed the roles of prostatic lipids on the pathogenesis, progression and discovery of diagnostic and prognostic biomarkers of PCa. In addition, this animal model was excellent to investigate prognostic lipid biomarkers in differentiation of indolent from aggressive PCa.

Background

It remains under-investigated whether prostatic lipid profiles are associated with pathogenesis, progression, racial disparity, and discovery of biomarkers in prostate cancer (PCa).

Methods

The electrospray ionization-tandem mass spectrometry was applied to quantitate prostatic lipids in human and mouse PCa and non-cancer prostatic tissues. Biostatistics and bioinformatics were used to compare the concentrations of prostatic lipids at levels of total lipid, group, class and individual species between PCa and benign prostatic tissues, between races, and among pathological conditions of PCa.

Results

Prostatic concentrations of total lipids as well as neutral lipids were significantly higher in PCa than in benign prostatic tissues in all population and Caucasian American population, but not in African American population. The prostatic phospholipid were not statistically different between PCa and benign prostatic tissues in all study populations. Cholesteryl ester is the only lipid class significantly higher in PCa than in benign prostatic tissues in all study populations. A panel of prostatic lipid parameters in each study population was identified as diagnostic and prognostic biomarkers with >60% of sensitivity, specificity and accuracy simultaneously. Lipid profiling on mouse prostatic tissues further confirmed correlation of prostatic lipid profiles to the pathogenesis and progression of PCa. In addition, a few prostatic lipids in mouse can serve as prognostic biomarkers in differentiation of indolent from aggressive PCa.

Conclusion

The prostatic lipids are widely associated with the pathogenesis, progression and racial disparity of PCa. A panel of prostatic lipids can serve as diagnostic, prognostic and race-specific biomarkers for PCa.

IMPROVE, a community-based exercise intervention versus support group to improve functional and health outcomes among older African American and Non-Hispanic White breast cancer survivors from diverse socioeconomic backgrounds: Recruitment strategies and baseline characteristics

BACKGROUND

Behavioral intervention studies in older breast cancer survivors, particularly older African American (AA) and socioeconomic status-disadvantaged breast cancer survivors, are lacking. To inform future studies, the authors examined recruitment strategies in older breast cancer survivors who participated in an exercise intervention study.

METHODS

IMPROVE is a randomized trial designed to evaluate a group-based exercise intervention versus a support group (ClinicalTrials.gov identifier, NCT02763228). Participants were aged ≥65 years who had survived stage I through III breast cancer and were within 5 years of treatment completion. Participants were recruited through multiple approaches, including peripheral, linguistic, and constituent-involving strategies that incorporated the identification of potentially eligible patients from 3 local hospitals and from State of Ohio registries and through direct clinician and community organization referrals.

RESULTS

Between October 2016 and November 2019, 7487 patients were screened, 4790 were potentially eligible, and 213 were randomized into the study. The eligible:randomization rates were 4.4% overall and 84%, 8%, and 2% for recruitment using direct referrals, hospital registries, and state registries, respectively. The median age of the randomized cohort was 70 years (range, 65-88 years) and included 44% AA and 44% socioeconomic status-disadvantaged breast cancer survivors. Compared with all registry-eligible patients, directly referred-eligible patients were more likely to be AA versus Non-Hispanic White (41% vs 19%; P = .006), to be contacted successfully (100% vs 33%; P < .0001), and to accept study participation (88% vs 16%; P < .0001).

CONCLUSIONS

Direct referrals appeared to be the most efficient strategy for recruiting AA survivors. Behavioral intervention studies seeking to target older AA and socioeconomic status-disadvantaged breast cancer survivors should include strategies that foster direct referrals to study participation.

Case Series: COVID-19 in African American Patients With Sarcoidosis

Data on the clinical presentation and outcomes of sarcoidosis patients with coronavirus disease 19 (COVID-19) are scarce. In this case series, we identified 5 out of 238 sarcoidosis patients who are enrolled in an ongoing longitudinal observational study who developed COVID-19 during the study period and follow their clinical course. Four patients recovered completely, whereas one patient expired during hospital admission. Our preliminary experience suggests that African American patients with chronic sarcoidosis treated with disease-modifying anti-rheumatic drugs (DMARDs) or anti-tumor necrosis factor (TNF) therapy do not seem to be at increased risk of respiratory or life-threatening complications from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compared with the general population, although at the present time, we advocate for maintaining a high level of vigilance and strict follow-up in this patient population.

Understanding breast cancer disparities-a multi-scale challenge

Despite convergence of overall breast cancer incidence rates between European American (EA) and African American (AA) women, disparities in mortality persist. The factors contributing to differences in mortality rates across population groups remain controversial and range from population genetics to sociodemographic influences. This review explores the complex multi-factorial nature of tumor-intrinsic and -extrinsic factors that impact the biology and clinical outcomes of breast cancer patients. In addition to summarizing the current state of breast cancer disparities research, we also motivate the development of integrative multi-scale approaches involving interdisciplinary teams to tackle this complex clinical challenge.

Distribution and clinical relevance of phospholipids in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is the most common liver cancer and featured with prominent disparity in incidence and mortality rate between male and female. It remains unclear whether alterations of phospholipids (PL) in hepatic tissues contribute to the pathogenesis, progression, and disparity of HCC.

Methods

Using electrospray ionization mass spectrometry (ESI–MS), PL profiles including 320 individual phospholipid species in 13 PL classes were determined in paired samples from HCC and adjacent benign hepatic tissues (BHT).

Results

(1) Concentrations of PLs in most of individual species, in subgroups and in total were decreased in HCC than in BHT in all studied population; (2) the number of individual PL species significantly different between HCC and BHT, and the number of PLs in six subgroups and in total decreased in HCC were more in male population than in female population; (3) panels of PL parameters (more in male population than in female population) were identified as biomarkers in differentiation of HCC from BHT, and in the prediction of pathological grade and clinical stage of HCC with high sensitivity, specificity, and accuracy.

Conclusion

It is concluded that alterations of PLs in hepatic tissues play important roles in pathogenesis, progression, and gender disparity of HCC.

Electronic supplementary material

The online version of this article (10.1007/s12072-020-10056-8) contains supplementary material, which is available to authorized users.

Vitamin D and Abdominal Aortic Calcification in Older African American Women, the PODA Clinical Trial

Abdominal aortic calcification (AAC) detected on lateral vertebral fracture assessment is associated with increased cardiovascular risk. Vitamin D deficiency and toxicity have been linked with vascular calcification. The objective of this study was to determine the effect of high-dose vitamin D on the progression of AAC. The Physical Performance, Osteoporosis and vitamin D in African American Women (PODA) is a randomized, clinical trial examining the effect of vitamin D. There were 14.7% subjects with AAC in the vitamin D group, compared to 12.1% in the placebo group at baseline. The prevalence of extended AAC at baseline was 6.4% in the vitamin D group and 3.5% in the placebo group. The extended calcification scores over time were not different between groups. There was no association between AAC and serum 25(OH)D. However, PTH was associated with an increase in AAC in the placebo group.

The Effects of APOE and ABCA7 on Cognitive Function and Alzheimer's Disease Risk in African Americans: A Focused Mini Review

African Americans have double the prevalence of Alzheimer's disease (AD), as compared to European Americans. However, the underlying causes of this health disparity are due to a multitude of environmental, lifestyle, and genetic factors that are not yet fully understood. Here, we review the effects of the two largest genetic risk factors for AD in African Americans: Apolipoprotein E (APOE) and ABCA7. We will describe the direct effects of genetic variation on neural correlates of cognitive function and report the indirect modulating effects of genetic variation on modifiable AD risk factors, such as aerobic fitness. As a means of integrating previous findings, we present a novel schematic diagram to illustrate the many factors that contribute to AD risk and impaired cognitive function in older African Americans. Finally, we discuss areas that require further inquiry, and stress the importance of racially diverse and representative study populations.

Rethinking active surveillance for prostate cancer in African American men

Active surveillance (AS) is a treatment modality for prostate cancer that aims to simultaneously avoid overtreatment and allow for the timely intervention of localized disease. AS has become the de facto standard of care for most men with low-risk prostate cancer. However, few African American (AA) men were included in the prospective observational cohorts that resulted in a paradigm shift in treatment recommendations from active intervention toward AS. It has been established that AA men have an increased prostate cancer incidence, higher baseline prostate-specific antigen (PSA) values, more aggressive prostate cancer features, greater frequency of biochemical recurrence after treatment, and higher overall cancer-specific mortality compared to their Caucasian counterparts. As such, this has given many physicians pause before initiating AS for AA patients. In the following manuscript, we will review the available literature regarding AS, with a particular focus on AA men. The preponderance of evidence demonstrates that AS is as viable a management method for AA with low-risk prostate cancer as it is with other racial groups.

Racial/Ethnic Disparity in Rates and Outcomes of Total Joint Arthroplasty

Racial/ethnic disparity in total joint arthroplasty (TJA) has grown over the last two decades as studies have documented the widening gap between Blacks and Whites in TJA utilization rates despite the known benefits of TJA. Factors contributing to this disparity have been explored and include demographics, socioeconomic status, patient knowledge, patient preference, willingness to undergo TJA, patient expectation of post-arthroplasty outcome, religion/spirituality, and physician-patient interaction. Improvement in patient knowledge by effective physician-patient communication and other methods can possibly influence patient's perception of the procedure. Such interventions can provide patient-relevant data on benefits/risks and dispel myths related to benefits/risks of arthroplasty and possibly reduce this disparity. This review will summarize the literature on racial/ethnic disparity on TJA utilization and outcomes and the factors underlying this disparity.

Differential Impact of Multiple Sclerosis on Cortical and Deep Gray Matter Structures in African Americans and Caucasian Americans

BACKGROUND

African Americans with multiple sclerosis (AAwMS) have different disease phenotypes when compared to Caucasians Americans with MS (CAwMS). The pathologic basis of this difference in disease presentation is unknown.

METHODS

Fifty-Four AAwMS and 54 CAwMS were appropriately matched for age, gender, treatment duration, and disease duration. FreeSurfer was used to segment brain white matter and gray matter from T1 images and compute thalamic volume. Regional cortical thickness was calculated using QDEC.

RESULTS

The 2 matched cohorts differed in disability, with AAwMS demonstrating significantly higher EDSS scores (2.3±2.2 vs. 1.3±1.5, P < .009), yet the 2 populations had similar T2 hyperintense lesion volumes (P = .35). AAwMS had a significantly lower total global cortical thickness when compared to CAwMS (P = .03). Controlling for EDSS, AAwMS showed multiple cortical regions to be significantly thinner than CAwMS; these included areas within the temporal, parietal and occipital lobes, as well as the precentral and postcentral gyrus. Middletemporal cortex was most affected in AAwMS in the left hemisphere (P = .009), while the superiortemporal cortex was most affected in the right hemisphere (P = .0001). In contrast, thalamic volume was significantly reduced in CAwMS when compared to AAwMS (P = .01). In both groups, worse disability was associated with lower total thalamic volume percentage.

CONCLUSION

AAwMS and CAwMS patients differ with regard to global and regional cortical thickness and thalamic volume. This diverging pattern of gray matter volumetrics among otherwise matched patients suggests that racial-specific disease differences may exist.