Microbial Differences in Prostate Lesions Between Black and White American Men

Ethnicity and pathological factors contribute to differences in prostate neoplasm, and this landscape could be influenced by the local microbiome.

To investigate whether prostate tissue harbors race-specific microbiota, we performed 16S rRNA gene sequencing of various hypervariable regions of cancer, inflammation, and non-cancer (benign) tissue from Black and White American men with prostate cancer followed by qRT-PCR for validation. All reported p-values were adjusted for false discovery rate to account for multiple comparisons.

Comparative analysis revealed marked differences in microbial composition between the two groups. Several species showed significant differential abundance, including Alphaproteobacteria (p < 0.001), Bacteroides fragilis (p < 0.001), Candidatus Kerfeldbacteria (p < 0.001), Flavobacterium frigoris (p < 0.0001), Fusobacterium nucleatum (p < 0.003), Rhizobiales bacterium (p < 0.0001), Sphingomonas glacialis (p < 0.0001), and Staphylococcus epidermidis (p < 0.05). Lesion-specific analysis further identified Pseudomonadota, Actinomycetota, and Bacilliota as the most abundant phyla in inflammatory lesions of both racial groups. However, Tenericutes were uniquely present in Black American samples, whereas Bacteroidota and Deinococcota were more abundant in the inflammatory lesions of White American men. At the genus level, analysis identified several key bacterial taxa associated with prostate cancer. Streptococcus, Abiotrophia, and Acinetobacter were significantly enriched in the Black American prostate tissues, while Staphylococcus and Corynebacterium were more abundant in tissue from White American men.

This is the first study to demonstrate significant microbial diversity and distinct microbial signatures in Black and White American men, suggesting that intra-prostatic bacteria may play a role in disease disparities and pathogenesis.