Assessing Immuno-Expression of p53 Protein and TP53 Gene Amplification in Histologically Negative Surgical Margins of Oral Squamous Cell Carcinoma Patients and Normal Oral Mucosa

Background

About 30% of patients with Oral Squamous Cell Carcinoma (OSCC) develop a Local Recurrence (LR) even with histologically tumor-free surgical margins (HNMs). Hence, molecular analysis of the HNMs before the occurrence of any morphological changes is of paramount importance. The present study aimed to assess and compare the immunoexpression of p53 and TP53 gene amplification in normal oral mucosa and histologically negative surgical margins of Oral Squamous Cell Carcinoma (OSCC) along with the correlation with LR and survival.

Methods

Formalin-fixed paraffin-embedded tissue blocks of 40 HNMs of OSCC and 40 normal oral mucosa samples were analyzed for p53 immunostaining and TP53 gene amplification by PCR.

Results

Significantly higher positivity was noted with p₅₃ immuno-expression, TP53 gene amplification, and combined p₅₃ and TP53 expression in the study group than the control group (p<0.05). Although, statistically insignificant, most of the cases that showed LR and succumbed to mortality; were positive for p53 immuno-expression, TP53 gene amplification, and combined p53 and TP53 expression. Kaplan-Meier survival analysis showed that subjects with TP53 and combined p53 and TP53 positivity had decreased survival rate than their negative counterparts.

Conclusion

Detection of p53 in HNMs of OSCC can be used as a biomarker to identify those patients who are at high risk to develop LR and to predict survival. Combined p53 and TP53 assessment to be more reliable for predicting LR to help clinicians/surgeons for treatment planning.

Author(s): Shankargouda Patil, Mamata S Kamat, Rudrayya S Puranik, Bhagavan Das Rai A and BR Patil

Abstract | Full-Text | PDF

Share This Article