Table 5.

Clinical Studies of Glutathione Levels in Head and Neck Cancers

Study	Ptsa	Cancer Site / Typeb	Tumor Glutathione Levelsc	γGTd	Controle	Ratiof (T/C)
(Balasenthil et al. 2000)	10	Oral SQ	26.5 ± 2.6 mg/100g-tissue	Y	H	1.3*
(Caglar et al. 2001)	28	Larynx SQ	0.69 ± 0.73 μmol/g-tissue	Y	P	1.0
(Ferruzzi et al. 2003)	23	Oral, Oropharynx, Larynx SQ	34.8 ± 17.4 nmol/mg-protein	Y	P	1.4*
(Fiaschi et al. 2005)	18	Oral SQ	25.71 ± 4.976 nmol/mg-protein	Y	P	2.2*
					H	5.9*
(Guichard, 1990)	17	Oral, Oropharynx	21.5 ± 9.4 nmol/mg-protein	?	H	0.92
(Inci et al. 2003)	20	Larynx SQ	23.39 ± 5.8 nmol/mg-protein All tumors	Y	P	1.5*
			22.63 ± 7.51 Stage I/II
			24.23 ± 3.45 Stage III
(Janot et al. 1993)	9	Sinus SQ	47 ± 20 nmol/mg-protein	Y	P	2.4*
(Kacakci et al. 2009)	30	Larynx SQ	30.14 ± 6.37 mg/mg-protein	Y	H	1.0
(Kolanjiappan, Ramachandran and Manoharan 2003)	48	Oral SQ	10.90 ±1.30 nmol/mg-protein Stage II	Y	H	1.6*
			15.8 ± 1.30 Stage III			2.3*
			20.90 ± 4.20 Stage IV			3.1*
(Lafuente et al. 1998)	37	Larynx SQ	93.05 ± 68.93 nmol/mg-protein	N	P	1.9*
(Mulder et al. 1995)	25	Oral/Oropharynx	26.9 ± 1.6 nmol/mg-protein (Oral)	Y	P	0.88
		Larynx SQ	40.9 ± 4.9 (Larynx)			1.7*
(Nagini, Manoharan and Ramachandran 1998)	24	Oral SQ	17.40 ± 4.27 nmol/mg-protein	Y	H	2.8*
(Parise et al. 1994)	18	Oral, Oropharynx; Larynx. Hypopharynx	15.2 ± 8.2 nmol/mg-protein All tumors	Y	P	1.8*
			13 ± 6 Stage II			1.3
			16 ± 9 Stage III			2.2
			17 ± 10 Stage IV			2.1*
(Patel et al. 2007; Patel et al. 2008)	32	Oral SQ	0.0112 ± 0.00086 mmol/dL	?	P	0.75*
(Sadani & Nadkarni 1996)	44	Thyroid	3.4 ± 0.6 F Adenomag μM/g-tissue	Y	H	1.2*
			2.8 ± 0.1 F Carcinoma			0.97
			3.4 ± 0.4 P Carcinoma			1.2*
(Saroja, Balasenthil and Nagini 1999)	33	Oral SQ	29.56 ± 3.87 mg/100g-tissue	Y	H	1.4*
(Somashekar et al. 2011)	22	Oral, Larynx		N	P	≫1*
(Subapriya et al. 2002)	24	Oral SQ	~28 mg/100g-tissue	?	P	1.4*
(Wong et al. 1994)	26	Oral Epidermoid	24.36 ± 18.03 nmol/mg-protein	Y	P	8.0*
		Carcinoma			H	5.0*

^aNumber of patients.

^bSQ, squamous cell carcinoma.

^cConcentration of glutathione or thiols in tissue. Numbers in italics indicates reports of non-protein sulfhydryls rather than glutathione.

^dDenotes whether degradation by γ-glutamyltranspeptidase was prevented (Y) or not (N) by sample processing methods.

^eDisease free tissue from healthy controls (H); peritumoral tissue (P) or benign lesion (B).

^fRatio of tumor glutathione to control tissue levels. Gray shading indicates statistically significant T/C<1

^gThis study reported levels in Follicular Ademona, Follicular Carcinoma, Papillary Carcinoma

^*Asterisk indicates statistically significant differences in glutathione levels