Background: One of the main characteristics of oral squamous cell carcinoma (OSCC) is genetic alteration in specific target regions. Allelic imbalance in tumor suppressor genes is the key event in OSCC which is associated with loss of heterozygosity mostly on chromosome 9p21 locus which includes p16 marker. p16 (D9S1747) is a microsatellite marker which detects early changes in OSCC. To redefine more clearly the role of D9S1747 (p16 microsatellite marker) and its expression in OSCC, the study was designed with the aim to check the detection of D9S1747 in OSCC and to compare the same with histopathological grades and tumor node metastasis staging.
Materials and methods: Forty cases of paraffin-embedded tissue section which was histologically confirmed as OSCC and 10 cases of normal tissues were retrieved from the archives. DNA was extracted from the tissue sections and subjected for polymerase chain reaction to detect p16 microsatellite marker D9S1747. Data were analyzed using Chi-square test and Fisher's exact test.
Results: Twenty-seven cases (67.5%) showed p16 microsatellite marker positivity for OSCC. It was observed that 44.4%, 51.9% and 3.7% p16 microsatellite markers were positive in Stage 1, Stage 2 and Stage 4 OSCC cases, respectively. p16 microsatellite marker positivity was found in 77.8%, 22.2% and 0% for well-differentiated, moderately differentiated and poorly differentiated OSCC cases, respectively.
Conclusion: The observations of the present study revealed D9S1747 marker as an early event in OSCC, and this can be used as a prognostic marker.
Keywords: D9S1747; normal mucosa; oral squamous cell carcinoma; p16 microsatellite marker; polymerase chain reaction.