Gut microbiota, especially human pathogens, has been shown to be involved in the occurrence and development of cancer. Esophageal squamous cell carcinoma and lung cancer are two malignant cancers, and their relationship with gut microbiota is still unclear. Virulence factor database (VFDB) is an integrated and comprehensive online resource for curating information about human pathogens. Here, based on VFDB database, we analyzed the differences of bacteria at genus level in the gut of patients with esophageal squamous cell carcinoma, lung cancer, and healthy controls. We proposed the possible cancer-associated bacteria in gut and put forward their possible effects. Apart from this, principal coordinate analysis (PCoA) and analysis of similarities (ANSOIM) suggested that some bacteria in the gut can be used as potential biomarkers to screen esophageal squamous cell carcinoma and lung cancer, and their effectiveness was preliminary verified. The relative abundance of Klebsiella and Streptococcus can be used to distinguish patients with esophageal squamous cell carcinoma and lung cancer from healthy controls. The absolute abundance of Klebsiella can further distinguish patients with esophageal squamous cell carcinoma from patients with lung cancer. In particular, the relative abundance of Fusobacterium can directly distinguish between patients with esophageal squamous cell carcinoma and healthy controls. Additionally, the absolute abundance of Haemophilus can distinguish lung cancer from healthy controls. Our study provided a new way based on VFDB database to explore the relationship between gut microbiota and cancer, and initially proposed a feasible cancer screening method.

肠道微生物群，尤其是人类病原体，已被证明与癌症的发生和发展有关。食管鳞癌和肺癌是两种恶性肿瘤，它们与肠道菌群的关系尚不清楚。毒力因子数据库 (VFDB) 是一个综合而全面的在线资源，用于管理有关人类病原体的信息。在这里，我们基于 VFDB 数据库，分析了食管鳞癌患者、肺癌患者和健康对照组肠道内细菌属水平的差异。我们提出了肠道中可能的癌症相关细菌，并提出了它们可能的作用。除此之外，主坐标分析（PCoA）和相似性分析（ANSOIM）表明，肠道中的一些细菌可作为潜在的生物标志物用于筛查食管鳞癌和肺癌，其有效性得到初步验证。相对丰度克雷伯氏菌和链球菌可用于区分食管鳞状细胞癌和肺癌患者与健康对照。克雷伯氏菌的绝对丰度可以进一步区分食管鳞癌患者和肺癌患者。特别是梭杆菌的相对丰度可以直接区分食管鳞癌患者和健康对照。此外，嗜血杆菌的绝对丰度可以将肺癌与健康对照区分开来。我们的研究为探索肠道菌群与癌症之间的关系提供了一种基于VFDB数据库的新方法，并初步提出了一种可行的癌症筛查方法。