GSTP1 and oral cavity squamous cell carcinoma: Tremblay et al. [41] recruited 42 young patients (age: 21-40 years) with oral squamous cell carcinomas (OSCCs) and 62 older (age: 60-95 years) OSCCs patients to detect GSTP1 expression in tumor tissues and found a significantly decreased expression of GSTP1 in the tumors of young patients compared to their nondysplastic mucosa, but an increased expression of GSTP1 in tumors of older patients compared with their nondysplastic mucosa [41].