Recently, we focused on the project that intestinal bacterial products are involved in the occurrence and development of digestive system tumors. We found for the first time that when gut-derived bacterial products reach the liver through the portal vein, they can activate the bacterial recognition receptor NOD2. NOD2 receptor then enter the nucleus, causing nuclear autophagy and genomic instability which promotes the malignant transformation of normal hepatocytes into tumor cells. We predict NOD2 as a new therapeutic target for liver cancer. We further discovered that intestinal bacterial products also participate in the occurrence and development of gastrointestinal stromal tumors by affecting NLRP3 inflammatory bodies and changing the tertiary lymphoid structure of tumors. What's more, gut-derived bacterial products also regulate the variable splicing process of mRNA and participate in the occurrence and development of pancreatic cancer by affecting the level of long-chain non-coding RNA. We also pay much attention to clinical transformation of scientific research results. For example, we are studying on a drug used for treating liver cirrhosis for its new application on tumors.