Sub-species niche specialization in the oral microbiome is associated with nasopharyngeal carcinoma risk in an endemic area of southern China

Nasopharyngeal carcinoma (NPC) is a globally rare cancer, with a unique geographic distribution. In endemic areas including Southern China, the incidence is more than 20 times higher than the rest of the world. Although recent evidence suggests poor oral hygiene is a risk factor for NPC, it remains unknown whether the disease status is associated with changes in the oral microbiome. Therefore, we carried out a population-based case-control study in an endemic area of southern China. We analyzed microbial communities from 499 untreated incident NPC cases and 495 age and sex frequency-matched controls. Here, we show the oral microbiome is altered in patients with NPC: patients have lower microbial diversity and significant changes in the overall structure of their microbial communities which cannot be attributed to other factors. Furthermore, the combination of two closely related amplicon sequence variants (ASVs) from Granulicatella adiacens an individual carried were predicted by disease status. These ASVs sat at the center of a network of closely-related co-excluding organisms, suggesting that NPC may be associated with subtle changes in the oral microbiome.