Pre-operative radio-chemotherapy enhances apoptotic cell death in oral squamous cell carcinoma

• Published in: Journal of oral pathology & medicine 1998-09, Vol.27 (8), p.382-387
• Main Authors: Doi, Rieko, Makino, Takafumi, Adachi, Hironobu, Ryoke, Kazuo, Ito, Hisao
• Format: Article
• Language: English
• Subjects: Adult; Aged; Apoptosis; Biological and medical sciences; Carcinoma, Squamous Cell - metabolism; Carcinoma, Squamous Cell - pathology; Carcinoma, Squamous Cell - therapy; Chemotherapy, Adjuvant; Dentistry; Female; Humans; Immunohistochemistry; key words: apoptosis; Ki-67 Antigen - metabolism; Male; Medical sciences; Middle Aged; Mouth Neoplasms - metabolism; Mouth Neoplasms - pathology; Mouth Neoplasms - therapy; oral squamous cell carcinoma; Otorhinolaryngology. Stomatology; Preoperative Care; radio-chemotherapy; Radiotherapy, Adjuvant; Tumor Suppressor Protein p53 - metabolism; Tumors; TUNEL; Upper respiratory tract, upper alimentary tract, paranasal sinuses, salivary glands: diseases, semeiology
• ISSN: 0904-2512; 1600-0714
• DOI: 10.1111/j.1600-0714.1998.tb01971.x

The effect of pre‐operative radio‐chemotherapy (RCT) has been examined in a total of 15 oral squamous cell carcinomas (SCCs), in terms of apoptosis (cell loss) and proliferation. All the patients received pre‐operative radiation at a dosage of 30 or 40 Gy, as well as anticancer agents including tagaful (FT), 5‐fluorouracil (5‐FU), bleomycin (BLM) and peplomycin (PEP). Surgical specimens were obtained before and after RCT, and serial sections were prepared for immunohistochemistry for p53 oncoprotein and Ki‐67 antigen, as well as for terminal deoxynucleotidyl transferase (TdT)‐mediated dUTP‐biotin nick end labeling (TUNEL). TUNEL indices (TI; percentage of TUNEL‐positive cells in the tumor cells) before and after RCT were 1.2±1.1 and 4.7±2.9 in the nine well‐differentiated oral SCCs, and 1.0±0.7 and 3.9±2.1 in the six poorly differentiated SCCs, respectively. Similarly, Ki‐67 indices (KI; percentage of Ki‐67 antigen‐positive cells in tumor cells) before and after RCT were 31.1±14.2 and 15.8±11.1 in the former, and 37.1±7.8 and 8.7±13.4 in the latter, respectively. Thus, pre‐operative RCT enhanced apoptotic cell death and abated proliferative activity significantly (P < 0.05), regardless of histological differentiation. Enhancement of apoptosis was more prominent in the group treated with FT or 5‐FU than with BLM or PEP. Oral SCC with > 20% of nuclear p53‐positive tumor cells was noted in six cases. Enhanced TI and abadement of KI did not differ among the p53‐positive and ‐negative tumors.