Table 1.

Role of IL-17 in CRC.

Species	Mediators	Findings	References
Tumor promoting role
Human	VEGF	IL-17 induces both CRC cell lines and primary cancer cells to produce VEGF.	[52]
Human	HIF-1α and c-myc	IL-17 and TNFα cooperatively stimulate glycolysis in CRC cells via induction of HIF-1α and c-myc expression.	[45]
Mouse	Stat 3	IL-23/IL-17 signaling activated by microbial products promotes STAT3 phosphorylation in CRC epithelial cells.	[48]
Mouse	VEGF, KC, and PGE2	IL-17 promotes angiogenesis via induction of a variety of proangiogenic factors secretion from fibroblasts and tumors.	[36]
Mouse	IL-6, IL-23, and IL-1β; KC and Cox-2; CD4 T cells	IL-6, IL-23, IL-1β, KC, and Cox-2 are decreased and function of CD4 T cells alters in ApcMin/+ mice, resulting in abrogating spontaneous intestinal tumorigenesis.	[17]
Mouse	IL-6, STAT3, and TNF-α; cyclin D1, cyclin-dependent kinase 2, and cyclin E	IL-17A knockout decreases IL-6, STAT3, TNF-α, cyclin-D1, cyclin-dependent kinase 2, and cyclin E and inhibits CAC tumorigenesis.	[46]
Mouse	G-CSF, VEGF, and Bv8 NF-κB and ERK signaling	IL-17 induces the expression of G-CSF through NF-κB and ERK signaling, enhancing proangiogenic function via VEGF and Bv98 and promoting tumor growth.	[50]
Tumor inhibiting activity
Mouse	IFN-γ  NK cells and T cells	IL-17-deficient decreases IFN-γ + NK and tumor-specific IFN-γ + T cells and promotes tumor growth and lung metastasis.	[53]
Human	Claudin ERK MAPK pathway	IL-17 enhances the development of the tight junctional barrier mediated by claudin of T84-cell monolayers via ERK MAPK pathway in intestine.	[54]