ABSTRACT
Objective To investigate the expression of mitochondrial autophagy-associated protein PINK1 and Parkin in parotid pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma(CA-EX-PA). Methods The expression of PINK1 and Parkin were detected by immunohistochemistry in 24 cases of normal parotid gland tissues, 32 cases of PA tissues and 42 cases of CA-EX-PA tissues. The correlations of PINK1 and Parkin expression with the clinicopathologic characteristics of CA-EX-PA patients were analyzed. Results The positive rates of PINK1 in normal parotid gland, PA and CA-EX-PA tissues were 100%, 91% and 67% respectively; and those of Parkin were 100%, 88% and 52% respectively. The expression rates of PINK1 and Parkin in PA and CA-EX-PA tissues were significantly lower than those in normal tissues (P < 0.05). The expression of PINK1 and Parkin protein were positively correlated in CA-EX-PA tissues (r=0.877, P < 0.01). In CA-EX-PA tissues, the expression of PINK1 and Parkin were associated with tumor invasion, lymph node metastasis and TNM stage (P < 0.05). Conclusion The expression of PINK1 and Parkin are decreased in PA and CA-EX-PA tissues. The decrease of mitochondrial autophagy activity might play important roles in the development, invasion and metastasis of parotid gland tumors.
ABSTRACT
Objective To explore the expression and significance of main autophagic regulatory factors of mTOR and Beclin 1 in benign and malignant pleomorphic adenoma .Methods The expression of Beclin1 in 35 cases of carcinoma in parotid pleomorphic adenoma(CPA) ,37 cases of benign pleomorphic adenoma(PA) and 20 cases and normal parotid tissues was measured by adopting the immunohistochemical staining method .The expression of p-mTOR and Beclin1 in CPA ,PA and normal parotid tissues was measured by Western blot .Results The positive expression of p-mTOR in normal parotid tissue ,parotid pleomorphic adenoma and parotid pleomorphic adenoma showed the increasing trend ,and the difference among them was statistically significant (P<0 .05) . The Beclin1 level in 3 kinds of tissue showed the descending trend ,the difference among the three tissues was statistically signifi-cant(P<0 .05) .Conclusion mTOR signal factor is over-expressed in CPA tissue ,while the positive expression of Beclin 1 is inhibi-ted in CPA tissue .