biostudies-literatureLiu YNIDDK NIH HHSNational Institute of Diabetes and Digestive and Kidney DiseasesNational Cancer InstituteNCI NIH HHSNIH HHSe29485https://www.ebi.ac.uk/biostudies/studies/S-EPMC10916714biostudies-literatureUnknown96(2)Emerging evidence supports a high prevalence of cancer type-specific microbiota residing within tumor tissues. The intratumoral microbiome in hepatocellular carcinoma (HCC), especially in viral (hepatitis B virus [HBV]/hepatitis C virus [HCV]) HCC, has not been well characterized for their existence, composition, distribution, and biological functions. We report herein a finding of specific microbial signature in viral HCC as compared to non-HBV/non-HCV (NBNC) HCC. However, the significantly diverse tumor microbiome was only observed in HBV-related HCC, and Cutibacterium was identified as the representative taxa biomarker. Biological function of the unique tumor microbiota in modulating tumor microenvironment (TME) was characterized by using formalin-fixed paraffin-embedded (FFPE) tissue-based multiplex immunofluorescence histochemistry (mIFH) allowing simultaneous in situ detection of the liver cancer cells surrounded with high/low density of microbiota, and the infiltrating immune cells. In HBV_HCC, the intratumoral microbiota are positively associated with increased tumor-infiltrating CD8+ T lymphocytes, but not the CD56+ NK cells. Two subtypes of myeloid-derived suppressor cells (MDSCs): monocytic MDSCs and polymorphonuclear MDSCs, were also found to be positively correlated with the intratumoral microbiota in HBV_HCC, indicating an inhibitory role of these microbial species in antitumor immunity and the contribution to the liver TME in combination of chronic viral hepatitis during HCC development.Journal of medical virologyHepatitis B virus-related hepatocellular carcinoma exhibits distinct intratumoral microbiota and immune microenvironment signatures.PMC10916714P30 DK120531P30 CA047904P30CA047904P30DK120531Liu YGuo HKim ESfalseHepatitis B virus-related hepatocellular carcinoma exhibits distinct intratumoral microbiota and immune microenvironment signatures.Emerging evidence supports a high prevalence of cancer type-specific microbiota residing within tumor tissues. The intratumoral microbiome in hepatocellular carcinoma (HCC), especially in viral (hepatitis B virus [HBV]/hepatitis C virus [HCV]) HCC, has not been well characterized for their existence, composition, distribution, and biological functions. We report herein a finding of specific microbial signature in viral HCC as compared to non-HBV/non-HCV (NBNC) HCC. However, the significantly diverse tumor microbiome was only observed in HBV-related HCC, and Cutibacterium was identified as the representative taxa biomarker. Biological function of the unique tumor microbiota in modulating tumor microenvironment (TME) was characterized by using formalin-fixed paraffin-embedded (FFPE) tissue-based multiplex immunofluorescence histochemistry (mIFH) allowing simultaneous in situ detection of the liver cancer cells surrounded with high/low density of microbiota, and the infiltrating immune cells. In HBV_HCC, the intratumoral microbiota are positively associated with increased tumor-infiltrating CD8+ T lymphocytes, but not the CD56+ NK cells. Two subtypes of myeloid-derived suppressor cells (MDSCs): monocytic MDSCs and polymorphonuclear MDSCs, were also found to be positively correlated with the intratumoral microbiota in HBV_HCC, indicating an inhibitory role of these microbial species in antitumor immunity and the contribution to the liver TME in combination of chronic viral hepatitis during HCC development.2024-01-01T00:00:00Z2024 Feb2025-04-05T10:19:09.564Z2025-04-05T10:19:09.564ZS-EPMC109167143837716710.1002/jmv.29485