Association between Circulating T Cells and the Gut Microbiome in Healthy Individuals: Findings from a Pilot Study.

Though the microbiome's impact on immune system homeostasis is well documented, the effect of circulating T cells on the gut microbiome remains unexamined. We analyzed data from 50 healthy volunteers in a pilot trial of aspirin, using immunophenotyping and 16S rRNA sequencing to evaluate the effect of baseline T cells on microbiome changes over 6 weeks. We employed an unsupervised sparse canonical correlation analysis (sCCA) and used multivariable linear regression models to evaluate the association between selected T cell subsets and selected bacterial genera after adjusting for covariates. In the cross-sectional analysis, percentages of naïve CD4+ T cells were positively associated with a relative abundance of Intestinimonas, and the percentage of activated CD8+ T cells was inversely associated with Cellulosibacter. In the longitudinal analysis, the baseline percentages of naïve CD4+ T cells and activated CD4+ T cells were inversely associated with a 6-week change in the relative abundance of Clostridium_XlVb and Anaerovorax, respectively. The baseline percentage of terminal effector CD4+ T cells was positively associated with the change in Flavonifractor. Notably, the microbiome taxa associated with T cell subsets exclusively belonged to the Bacillota phylum. These findings can guide future experimental studies focusing on the role of T cells in impacting gut microbiome homeostasis.

Hypertension and Risk of Endometrial Cancer: A Pooled Analysis in the Epidemiology of Endometrial Cancer Consortium (E2C2).

BACKGROUND: The incidence rates of endometrial cancer are increasing, which may partly be explained by the rising prevalence of obesity, an established risk factor for endometrial cancer. Hypertension, another component of metabolic syndrome, is also increasing in prevalence, and emerging evidence suggests that it may be associated with the development of certain cancers. The role of hypertension independent of other components of metabolic syndrome in the etiology of endometrial cancer remains unclear. In this study, we evaluated hypertension as an independent risk factor for endometrial cancer and whether this association is modified by other established risk factors. METHODS: We included 15,631 endometrial cancer cases and 42,239 controls matched on age, race, and study-specific factors from 29 studies in the Epidemiology of Endometrial Cancer Consortium. We used multivariable unconditional logistic regression models to estimate ORs and 95% confidence intervals (CI) to evaluate the association between hypertension and endometrial cancer and whether this association differed by study design, race/ethnicity, body mass index, diabetes status, smoking status, or reproductive factors. RESULTS: Hypertension was associated with an increased risk of endometrial cancer (OR, 1.14; 95% CI, 1.09-1.19). There was significant heterogeneity by study design (Phet < 0.01), with a stronger magnitude of association observed among case-control versus cohort studies. Stronger associations were also noted for pre-/perimenopausal women and never users of postmenopausal hormone therapy. CONCLUSIONS: Hypertension is associated with endometrial cancer risk independently from known risk factors. Future research should focus on biologic mechanisms underlying this association. IMPACT: This study provides evidence that hypertension may be an independent risk factor for endometrial cancer.

Blood Pressure, Hypertension, and Antihypertensive Medication Use and Risk of Total and Fatal Prostate Cancer in Black and White Men in the Atherosclerosis Risk in Communities (ARIC) Study.

Black men are disproportionately burdened by hypertension and prostate cancer (PCa), and some cohorts suggest hypertension is associated with increased PCa risk. We investigated the association of hypertension and antihypertensive use with total (N = 889; 290 Black, 599 White) and fatal (N = 127; 42 Black, 85 White) PCa risk in 6658 (1578 Black, 5080 White) men in the Atherosclerosis Risk in Communities study. In adjusted Cox models, time-updated untreated stage 1 hypertension (systolic/diastolic blood pressure 130-139/80-89 mmHg) was associated with a higher risk of fatal PCa compared to untreated normal blood pressure (hazard ratio (HR) = 1.95; 95% confidence interval (CI) = 1.03-3.70). Compared to untreated normal/elevated blood pressure (combined given few events in those with untreated normal blood pressure), the association was significant in Black (HR = 3.35; 95% CI = 1.27-8.83), but not White (HR = 1.21; 95% CI = 0.58-2.55) men. Ever antihypertensive use was associated with a lower risk of fatal PCa compared to never use (HR = 0.52; 95% CI = 0.31-0.87), including short-term (< 10 years) and long-term (310 years) use (p-trend = 0.02) with similar inverse associations in Black and White men. Hypertension and antihypertensive use were not significantly associated with total PCa. The positive association of untreated stage 1 hypertension and fatal PCa warrants additional confirmation, especially in Black men, and characterization of the underlying mechanism.