RESUMO
CpG site methylation patterns have potential to improve differentiation of high-grade screening-detected cervical abnormalities. We assessed CpG differential methylation (DM) and differential variability (DV) in high-grade (CIN2+) vs. low-grade (≤CIN1) lesions. In ≤CIN1 (n=117) and CIN2+ (n=31) samples, cervical sample DNA underwent testing with Illumina HumanMethylation arrays. We assessed DM and DV of CpG methylation M values among nine cervical cancer-associated genes. We fit CpG-specific linear models and estimated empirical Bayes standard errors and false discovery rates (FDR). An exploratory epigenome-wide association study (EWAS) aimed to detect novel DM and DV CpGs (FDR<0.05) and Gene Ontology (GO) term enrichment. Compared to ≤CIN1, CIN2+ exhibited greater methylation at CCNA1 Cluster 1 (M value difference 0.24; 95% CI 0.04, 0.43) and RARB Cluster 2 (0.16; 95% CI 0.05, 0.28), and lower methylation at CDH1 Cluster 1 (-0.15; 95% CI -0.26, -0.04). CIN2+ exhibited lower variability at CDH1 Cluster 2 (variation difference -0.24; 95% CI -0.41, -0.05) and FHIT Cluster 1 (-0.30; 95% CI -0.50, -0.09). EWAS detected 3,534 DM and 270 DV CpGs. Forty-four GO terms were enriched with DM CpGs related to transcriptional, structural, developmental, and neuronal processes. Methylation patterns may help triage screening-detected cervical abnormalities and inform US screening algorithms.
RESUMO
Background: Poor birth outcomes such as preterm birth/delivery disproportionately affect African Americans compared to White individuals. Reasons for this disparity are likely multifactorial, and include prenatal psychosocial stressors, and attendant increased lipid peroxidation; however, empirical data linking psychosocial stressors during pregnancy to oxidative status are limited. Methods: We used established scales to measure five psychosocial stressors. Maternal adverse childhood experiences, financial stress, social support, anxiety, and depression were measured among 50 African American and White pregnant women enrolled in the Stress and Health in Pregnancy cohort. Liquid chromatography-tandem mass spectrometry was used to measure biomarkers of oxidative stress (four urinary F2-isoprostane isomers), to estimate oxidative status. Linear regression models were used to evaluate associations between psychosocial stressors, prenatal oxidative status and preterm birth. Results: After adjusting for maternal obesity, gestational diabetes, and cigarette smoking, African American women with higher oxidative status were more likely to report higher maternal adverse childhood experience scores (ß = 0.16, se = 1.07, p-value = 0.024) and depression scores (ß = 0.05, se = 0.02, p = 0.014). Higher oxidative status was also associated with lower gestational age at birth (ß = -0.13, se = 0.06, p = 0.04) in this population. These associations were not apparent in Whites. However, none of the cross-product terms for race/ethnicity and social stressors reached statistical significance (p > 0.05). Conclusion: While the small sample size limits inference, our novel data suggest that psychosocial stressors may contribute significantly to oxidative stress during pregnancy, and preterm birth or delivery African Americans. If replicated in larger studies, these findings would support oxidative stress reduction using established dietary or pharmacological approaches present a potential avenue to mitigate adverse effects of psychosocial stressors on birth outcomes.