Table 2.

List of proteins tested as biomarkers of mucositis development and/or severity

Biomarker	Reference	Treatment	Disease	Origin	Levels during treatment	Significant association with OM
TNF-α	[123]	RT	HNC	Saliva	High	No
	[124]	RT	HNC	Cytologic smears from oral cavity	High	Association with OM development
	[125]	RT, RT + CT	HNC	Serum	Low	No
	[126]	RT, RT + CT	HNC	Serum	Low	No
IL-1	[125]	RT, RT + CT	HNC	Serum	No change	No
	[126]	RT, RT + CT	HNC	Serum	No change	No
IL-1β	[124]	RT	HNC	Cytologic smears from oral cavity	High	Association with OM development
IL-6	[123]	RT	HNC	Saliva	High	Association with OM severity
	[125]	RT, RT + CT	HNC	Serum	High	Association with OM severity
IL-8	[123]	RT	HNC	Saliva	High	No
	[125]	RT, RT + CT	HNC	Serum	High	No
IL-10	[123]	RT	HNC	Saliva	High	Association with OM severity
	[125]	RT, RT + CT	HNC	Serum	No change	No
TGF-β	[127, 128]	RT + CT	HNC	Plasma	High	Association with OM severity
EGF	[2, 129, 130]	RT	HNC	Saliva	Low	Association with OM development
	[131]	RT	HNC	Saliva	Low	Association with OM development
CRP	[132]	RT	HNC	Blood	High	Association with OM severity
	[133]	RT	HNC	Blood	High	Not assessed
	[134]	RT, RT + CT	HNC	Blood	High	Not assessed
	[135]	RT + CT	HNC	Blood	High	Association with OM severity only at initial week
ESR	[132]	RT	HNC	Blood	High	No
	[134]	RT, RT + CT	HNC	Blood	High	Not assessed
	[135]	RT + CT	HNC	Blood	High	No
GSH	[136]	RT	Oral cavity cancer	Plasma	Measured before RT	GSH baseline levels associate with OM development
	[137]	RT	HNC	Plasma	No change	No
DNA DSB (γ-H2AX)	[138]	RT	HNC	Peripheral blood lymphocytes	High	Association with OM severity
	[139]	RT, RT + CT	HNC	Peripheral blood lymphocytes	High	No