Table 6.

Mechanisms of resistance type 6 (MOC-6) in colorectal cancer.

Factor	Change	Drugs Affected	Consequences	Reference
HIF-1α	Upregulation	5-FU	MDR1 upregulation; lower response to treatment	[199]
	Upregulation	Bevacizumab	Lower apoptosis in resistant cells in vitro	[200]
HIF-1α, TGF-β	High expression	5-FU, Oxaliplatin	Increased GLI2 expression; lower drug effect in vitro	[201]
IL-17A	Increased production	5-FU, Oxaliplatin	Reduced drug effect on CSCs	[202]
Gut microbiota	Fusobacterium nucleatum	Oxaliplatin, Capecitabine	Lower response to treatment	[207]
	Gammaproteobacteria	Gemcitabine	Drug inactivation; reduced efficacy in vivo	[208]
UCA1	Upregulation	Cetuximab	Reduced drug efficacy in vitro and in patients	[209]

5-FU: 5-fluorouracil; CSC: cancer stem cells.