Expression And Clinical Significance Of P53and Autophagy-related Genes In Salivary Pleomorphic Adenoma And Carcinoma In Pleomorphic Adenoma

Objective:The purpose of this study was to investigate the expressions of p53, and autophagy-related genes Beclinl and LC3in carcinoma in pleomorphic adenoma (CIPA) and pleomorphic adenoma (PA), and the correlation between their expressions with clinical pathological features and clinical significance. The research may provide new ideas and experimental evidence for early diagnosis and biotherapy for PA in the future.Methods:20surgical specimens of CIPA and108specimens of PA were collected from the surgical pathology files of the Department of Pathology, Provincial Hospital Affiliated to Shandong University during the past5years from2007to2012. The expressions of protein of p53, LC3and Beclinl were detected by using of immunohistochemistry in these tissues. The results were used to analyze the relationships between these gene expressions with the developing of PA and clinical pathological features. Differences between marker expression estimation and SID score regarding the clinicopathologic parameters were conducted using Pearson’s x2test. Spearman’s test for non-normal correlation coefficients were used to evaluate the associations between Beclin-1and p53expressions. Statistic analysis was conducted with SPSS20. AP value<0.05was considered statistically significant.Results:1. P53, Beclin1and LC3protein expression in CIPA and PA: The protein expressions of mutant-type p53in PA tissues were significantly lower than that CIPA (p<0.001). The protein expressions of autophagy-related genes LC3and Beclinl in PA tissues were significantly higher than those in CIPA (p<0.001). These expression changes of autophagy-related genes LC3and Beclinl were associated with tumor variant of PA except mutant-type p53. But these expression changes of these three genes were not associated with gender, age strata, evolution course, tumor size, and location of PA (p>0.05). The protein expression of LC3and Beclinl were correlated with p53protein expression in PA(p<0.05).2. Correlations of p53and autophagy-related genes Beclinl and LC3expression toclinicopathologic features of pleomorphic adenoma patients: There were no significant differences between expression estimation and SID scores of the markers regarding the clinical prognostic parameters such as age, gender, size, evolution course, recurrence and location of the lesions(P>0.05)3. Correlations of p53and autophagy-related genes expressions in pleomorphic adenoma tissues:Regarding the correlation of Beclinl and LC3protein expressions with p53protein expression,4of9patients with p53protein-positive expression were positive for protein expression of Beclinl. The protein expressions of Beclinl and P53in PA were negatively correlated (r=-0.330, p<0.05);5of9patients with P53protein-positive expression were positive for protein expression of LC3. The protein expressions of P53and LC3in PA were also negatively correlated (r=-0.225, p<0.05)Conclusion:The activity changes of tumor inhibitor of growth, autophagy, and apoptosis may be related to the occurrence and the progression of PA. The combined detection of p53, LC3and Beclinl genes and proteins will be helpful for early diagnosis and prognosis judgment for PA, and may also provide clues for targeted cancer chemotherapy.