人体的共生菌群可以作为内源性致癌物或促癌物的来源之一，参与肿瘤的发生和演进。我们在前期研究发现，人鼻咽部具有独特而丰富的菌群结构，其中含有多种可代谢短链脂肪酸的厌氧菌，构成鼻咽部生理微环境的一部分。本研究将分析健康人鼻咽部的SCFA构成以及鼻咽癌患者鼻咽部SCFA构成的改变。进一步研究SCFA对EBV潜伏感染的影响、对正常鼻咽上皮细胞及鼻咽癌细胞生物学行为的改变，从病毒学和细胞生物学角度探讨鼻咽部SCFA是否参与EBV的潜伏感染乃至上皮细胞癌变的过程，及其可能机制。阐明细菌代谢产物作为鼻咽上皮细胞外环境如何与EBV交互作用，参与鼻咽癌的致癌过程。由此探寻鼻咽癌化学预防和早期干预的策略。

The human commensal bacteria can be one of the endogenous carcinogens or tumor promoters involved in tumorigenesis and progression. In previous study, we found a unique and rich microflora locating in human nasopharynx. A variety of anaerobes which may produce short chain fatty acids (SCFAs) was included. In this study, we will analyze the composition of SCFAs, as parts of the physiological microenvironment, in nasopharynx of healthy people and nasopharyngeal carcinoma (NPC) patients. To explore the function of SCFAs in carcinogenesis of NPC and its possible mechanism, we will evaluate their effects in turning EBV into lytic cycle and modulating the biological behavior of nasopharyngeal epithelial cells. Further, clarifying how do the metabolites from microflora interact with EBV and involve in the carcinogenesis of NPC will provide strategies for NPC prevention and early chemical intervention.