Expression And Significance Of KiSS-1 In Parotid Gland Carcinoma

Parotid gland carcinoma is the common malignancy in oral and maxillofacialregion which has the ability to invade and metastasize. The invasion and metastasisare an important character of malignant tumors and also are the main cause of deathof malignant tumors. Metastasis suppressor gene is a kind of gene associated withmalignant tumors.It has come into being with the development of molecule cloningtechnique.At present,several MSGs have been found,such as nm23,KAI1, MKK4,BRMS1 and KiSS-1. KiSS-1 was a novel tumor metastasis suppressor gene whichwas found in human melanoma cell lines by Lee in 1996.Studies showed that loss ofexpression of KiSS-1 is correlated with the invasion and metastasis of many kinds oftumors.Researchs on KiSS-1 and parotid gland carcnoma have not been reportedyet. Our experiment was to detect the expression of KiSS-1 protein metastin inparotid gland carcinoma by immunohistochemistry of streptavidin-perocidase (S-P)method and to explore the function of KiSS-1 in the invasion and metastasis ofparotid gland carcinoma.We collected 76 cases of parotid gland carcinoma tissues from oral andmaxillofacial surgery department of College of Stomatology, Sichuan University from 1997.1 to 2006.4. We took 10 cases of normal parotid tissue as the normalgroup. We detected the expression of metastin in them by immunohistochemistry ofstreptavidin-perocidase (S-P) method and analyzed the correlation between theexpression of metastin and clinicopathologic features such as gender,age,size,pathologic type,TNM classification,histologic grade,lymph node metastasis.The positive rate of metastin in normal parotid tissue was 100%, the location ofexpression was the plasma of duct epithelium cell. The positive rate of metastin inparotid gland carcinoma tissue was 64.5%, the location of expression was the plasmof tumor cell (P＜0.05).There was no correlation found between the expression ofmetastin in patients with patient's gender, age and size of tumor(P＞0.05). Theexpression ofmetastin in papillary cyst carcinoma and squamous cell carcinoma waslower than that in mucoepidermoid carcinoma and acinic cell carcinoma(P＜0.05).Asfor histological grade, the expression of metastin in gradeⅢmucoepidermoidcarcinoma was lower than that in gradeⅠ,Ⅱmucoepidermoid carcinoma(P＜0.05),there was no difference between gradeⅠand gradeⅡmucoepidermoidcarcinoma(P＞0.05). The expression of metastin in parotid gland carcinoma ofⅢ-Ⅳclinical stage was lower than that in parotid gland carcinoma ofⅠ-Ⅱclinicalstage(P＜0.05). The expression of metastin in parotid gland carcinoma with lymphnode metastasis was much lower than that in parotid gland carcinoma without lymphnode metastasis(P＜0.05).Based on these findings, the expression of KiSS-1 protein metastin in parotidgland carcinoma was lower than that in normal parotid tissue,it revealed that KiSS-1may be involved in the genesis of parotid gland carcinoma. The expression ofmetastin in gradeⅢmucoepidermoid carcinoma, papillary cyst carcinoma andsquamous cell carcinoma which are easy to invade and metastasize was lower than that in gradeⅠ,Ⅱmucoepidermoid carcinoma and acinic cellcarcinoma(P＜0.05),the expression of metastin in parotid gland carcinoma ofⅢ-Ⅳclinical stage was lower than that in parotid gland carcinoma ofⅠ-Ⅱclinicalstage(P＜0.05), the expression of metastin in parotid gland carcinoma with lymphnode metastasis was lower than that in parotid gland carcinoma without lymph nodemetastasis(P＜0.05).These differences of expression may prove that KiSS-1 is ametastasis supressor gene of parotid gland carcinoma.When the expression ofKiSS-1 becomes low, the invasion and metastasis are coming or already existed.KiSS-1 is important in predicting the prognosis and deciding treatment scheme ofparotid gland carcinoma.In the future,it is possible that we treat parotid carcinomawith gene therapy by using KiSS-1 as the target.