Neighborhood Disadvantage and Prostate Tumor Aggressiveness among African American and European American Men.

BACKGROUND: Studies have identified associations between neighborhood disadvantage (ND), which is more likely to affect African American (AA) individuals, and aggressive prostate cancer. Thus, ND may contribute to prostate cancer disparities. However, it is unknown what ND components drive aggressive disease and whether associations vary by race. METHODS: We evaluated associations between aggressive prostate cancer and four ND metrics-Area Deprivation Index (ADI), validated Bayesian Neighborhood Deprivation Index (NDI), racial isolation (RI) index, and historical redlining, and whether these factors interacted with race, among men with prostate cancer treated at the University of Maryland Greenebaum Comprehensive Cancer Center (2004-2021). RESULTS: We included 1,458 men (698 European American and 760 AA). AA men were more likely to experience ND. In adjusted models, the ADI, RI, and redlining were significantly associated with aggressive versus nonaggressive prostate cancer overall [ADI, OR for one SD increase = 1.14, 95% confidence interval (CI), 1.00-1.30; RI, OR = 1.27, CI, 1.07-1.51; redlining, OR = 1.77; CI, 1.23-2.56] and among AA men. The NDI was associated with aggressive prostate cancer among AA men (OR = 1.32, 95% credible interval: 1.13-1.57); percent in poverty received the largest importance weight. The ADI (P heterogeneity = 0.002) and NDI (exceedance probability heterogeneity = 98.1%) significantly interacted with race, such that associations were significantly stronger for AA men. CONCLUSIONS: We identified novel significant positive associations for racial segregation and historical redlining with aggressive prostate cancer and significant interactions between ND indices and race. IMPACT: Findings inform specific ND components that are associated with aggressive prostate cancer and suggest the ND effect is stronger for AA men, which has implications for interventions to reduce disparities.

Neighborhood Disadvantage and Prostate Tumor RNA Expression of Stress-Related Genes.

Importance: African American men experience greater prostate cancer incidence and mortality than White men. Growing literature supports associations of neighborhood disadvantage, which disproportionately affects African American men, with aggressive prostate cancer; chronic stress and downstream biological impacts (eg, increased inflammation) may contribute to these associations. Objective: To examine whether several neighborhood disadvantage metrics are associated with prostate tumor RNA expression of stress-related genes. Design, Setting, and Participants: This cross-sectional study leveraged prostate tumor transcriptomic data for African American and White men with prostate cancer who received radical prostatectomy at the University of Maryland Medical Center between August 1992 and January 2021. Data were analyzed from May 2023 to April 2024. Exposures: Using addresses at diagnosis, 2 neighborhood deprivation metrics (Area Deprivation Index [ADI] and validated bayesian Neighborhood Deprivation Index) as well as the Racial Isolation Index (RI) and historical redlining were applied to participants' addresses. Self-reported race was determined using electronic medical records. Main Outcomes and Measures: A total of 105 stress-related genes were evaluated with each neighborhood metric using linear regression, adjusting for race, age, and year of surgery. Genes in the Conserved Transcriptional Response to Adversity (CTRA) and stress-related signaling genes were included. Results: A total of 218 men (168 [77%] African American, 50 [23%] White) with a median (IQR) age of 58 (53-63) years were included. African American participants experienced greater neighborhood disadvantage than White participants (median [IQR] ADI, 115 [100-130] vs 92 [83-104]; median [IQR] RI, 0.68 [0.34-0.87] vs 0.11 [0.06-0.14]). ADI was positively associated with expression for 11 genes; HTR6 (serotonin pathway) remained significant after multiple-comparison adjustment (ß = 0.003; SE, 0.001; P < .001; Benjamini-Hochberg q value = .01). Several genes, including HTR6, were associated with multiple metrics. We observed higher expression of 5 proinflammatory genes in the CTRA with greater neighborhood disadvantage (eg, CXCL8 and ADI, ß = 0.008; SE, 0.003; P = .01; q value = .21). Conclusions and Relevance: In this cross-sectional study, the expression of several stress-related genes in prostate tumors was higher among men residing in disadvantaged neighborhoods. This study is one of the first to suggest associations of neighborhood disadvantage with prostate tumor RNA expression. Additional research is needed in larger studies to replicate findings and further investigate interrelationships of neighborhood factors, tumor biology, and aggressive prostate cancer to inform interventions to reduce disparities.