Table 3: Microbiome role in maturation of the immune system and involvement in cancer.

Microbiome componentsImmune cell developmentRole in cancerReferences

Firmicutes phylum: Fusobacterium nucleatum Direct killing of lymphocytes; Promotes metastasis and tumor growth[92]
Proteobacteria: E. coli, Citrobacter, Enterobacter, Shigella, Klebsiella, and Hemophilus Promotes TH17 Promotes cancer progression and metastasis[93]
Archea phylum: Eubacterium rectale IL-6 production by intestinal inflammatory dendritic cells Promotes cancer progression and metastasis[94]
Proteobacteria phylum: Sphingomonas species,CD8+ T cellsAnti cancer activities[91, 95]
Clostridium cluster IV-XIVa[22, 96101]
Actinobacterium phylum: Bifidobacterium Th1 noninflammatoryProtects against inflammation and cancer[102]