Overexpression of p53 protein in squamous cell carcinoma of buccal mucosa and tongue in Taiwan: an immunohistochemical and clinicopathological study

Abstract

Sixty squamous cell carcinomas of tongue and buccal mucosa were examined for expression of p53 protein by using an immunohistochemical technique improved by an antigen retrieval method. Twenty-seven (45%) tumors demonstrated strongly positive staining. Thirteen of p53-positive tumors (48%) also exhibited overexpression of p53 in immediately adjoining hyperplastic or pre-malignant epithelium. All 22 metastatic lymph nodes and 18 local recurrent lesions (except two) had an identical p53 immunophenotype to their corresponding primary sites. Mitotic indices were significantly higher in p53-positive tumors (P < 0.01); however, no association of PCNA scores with p53 expression was found (P > 0.1). There was no correlation between p53 overexpression and tumor grade, size and staging, vascular invasion, lymph node metastasis, and early local recurrence. Overexpression of p53 was found to be relatively higher, although not statistically significant, in nonsmokers than in heavy smokers (66.7% vs. 42.9%), and in nonbetel-quid chewers than in heavy chewers (62.5% vs. 34.2%). These data are consistent with the hypothesis that inactivation of p53 protein may occur in the early phases of oral tumorigenesis. It may not be a useful prognostic marker but could possibly be used for risk assessment and surveillance of local recurrence.

p53 Expression Helps Identify High Risk Oral Tongue Premalignant Lesions and Correlates with Patterns of Invasive Tumour Front and Tumour Depth in Oral Tongue Squamous Cell Carcinoma Cases

“…The results are similar to studies reported by Danieli et al, 2005 where they showed a 44% p53 positive expression in OTSCC. This is similar to the earlier studies from Indian population, 46%, 45%, 36% respectively (Yan et al, 1996;Saranath et al, 1999;Pillay et al, 2003).…”

Assessment of p53 Protein Expression in Leukoplakia, Oral Submucous Fibrosis and Oral Lichen Planus in Myanmar Patients

“…Increased p53 positive cells were detected in patients with betel quid chewing as well as smoking habits (Table 4). This is in contrast to the study of Yan et al, which showed that Taiwanese patients without a betel quid chewing habit had a higher rate of p53 overexpression than heavy chewers (18). Furthermore, alcohol drinking plays an important role in p53 alteration in southern Thailand (19).…”

Pathological Features of Betel Quid-Related Oral Epithelial Lesions in Taiwan with Special Emphasis on the Tumor Progression and Human Papillomavirus Association

“…Overexpression of the p53 protein and/or mutations of the p53 gene have been found in varying proportions of precancerous and malignant oral lesions, and most of them were associated with the consumption of BQ and tobacco [10, 11, 12, 36, 37]. It was, therefore, proposed that p53 alternations induced by carcinogens derived from BQ or tobacco were involved in the early development of oral cancer and may be helpful in identifying premalignant lesions [37, 38].…”

“…Mutations of the p53 gene play an important role in multistep carcinogenesis [9]. Overexpression of the p53 protein was found to be associated not only with oral cancers and premalignant lesions [10, 11, 12], but also with the histological grade of malignancy [13]. The carcinogenic pathway of overexpressed p53 protein has been suggested to synergize with bcl-2 overexpression, which occurs early in oral carcinogenesis resulting in defective apoptosis and subsequent tumor progression [14].…”