SSCP PATTERN INDICATIVE FOR P53 MUTATION IS RELATED TO ADVANCED-STAGEAND HIGH-GRADE OF TONGUE CANCER

p53 and bcl-2 are involved in the control of cell cycling and apoptosi s. Environmental factors such as smoking and radiation can disturb p53 function and predispose a cell to malignant transformation. To invest igate the role of p53 mutations, as well as p53 and bcl-2 protein expr ession in squamous cell carcinoma of the tongue, 39 samples were analy sed. Since neck metastasis is the most important prognostic factor of this disease, samples from patients both with and without nodal diseas e were selected to find out whether there was any difference between t he groups. Non-radioactive single-stranded conformation polymorphism ( SSCP) was used to screen p53 mutations; an altered SSCP pattern indica ting p53 mutation was found in 21 samples (54%). A significant correla tion between tumour size, histological differentiation and p53 mutatio ns was found (P<0.01). Immunocytochemically, nuclear expression of p53 was moderate or strong in 18 (46%) samples. No correlation between al tered p53 SSCP pattern and p53 immunoreactivity was seen. bcl-2 expres sion was cytoplasmic; moderate or strong staining was detected in only six of the carcinoma samples (15.5%). Interestingly, there was a sign ificant correlation between smoking and bcl-2 expression (P<0.01): all six samples with moderate or strong staining were taken from heavy sm okers. Furthermore, all those patients died within 32 months. Copyrigh t (C) 1996 Elsevier Science Ltd