402 “Glutathion system” and chemoresponse to 5-fluorouracil and cisplatine in head and neck squamous cell carcinoma: A pilot study

The relationship between the glutathione system and the chemoresponse to nea-adjuvant chemotherapy (CT) commonly used (cisplatine/5-fluorouracil: CDDP/5-FU) in head and neck squamous carcinoma (HNSCC). We assayed in the total blood of 38 patients (pt) the glutathione system before treatment (BT) and after 3 courses of CT. Objective response based on clinical examination (CE) and CT-Scan was achieved in 19/38 patients. The regression stage (RS) based on tumors histology obtained surgically (n = 28) after 3 courses of chemotherapy was achieved in 8/28 patients. Total glutathione (GSH), glutathione-S-transferase (GST) activity and GST-π content were assayed on cytosols of total blood. For each cycle and each pt, GST activity and GSH content were investigated by spectrophotometric assays, GST-π by Western blot. According to CE and RS, our results showed difference between non responders (NR) and objective responders pt (R) only for GST activity. The difference was significant after one course of CT [according to CE for NR (5 ± 2 nmoles/min/mg) and R (4 ± 2 nmoles/min/mg) ( P P