Study On Expression Of Proto-oncogene C-met In Laryngeal Carcinomas

[Objective] c-met proto-oncogene is a gene for hepatocyte growth factor receptor and express a transmembrane protein with tyrosine kinase activity .It is known to be associated with tumour development in several human carcinomas.Studies on c-met have improved greatly since Mr Cooper cloned met DNA in 1991.Comoglic studied c-met by Northern blot and Southern blot and he found that c-met is amplified and overexpressed in various human carcinomas such as gastric,thyroid gland, liver,kidney carcinomas. Sawatsubashi M found that positive reaction for c-met in neoplastic epithelium was noted in 45 out of 82 (54.9%) cases. In 44 cases, structures adjacent to the carcinoma (noncancerous squamous epithelium, some stromal fibroblastic cells, and endothelial cells) showed positive reaction for c-met. c-met expression in cancerous epithelium was significantly correlated with lymph node status (P<0.04). There was no correlation between c-met expression and age, sex, histological type, T category, distant metastasis or clinical stage. So he thought that overexpression of c-met in laryngeal carcinomas represents a growth advantage for cancer cells.Simultaneous c-met expression in noncancerous components of the larynx may represent a paracrinemodification of c-met.To study the expression of proto-oncogene c-met in human laryngeal carcinomas to find the assocication between protein expression of c-met and clinical pathological differentiation,stage andlymph nodes status of laryngeal carcinomas.[Methods] Using streptavidin - biotinimmuno -histochemistry(SABC),we studied 80 laryngeal squamous-cell carcinomas specimens and 60 vocal cord polyps with polyclonal antibodys of c-met .Disease stages were determined using the pTNM classification according to UICC criteria (1992).All specimens were approved by pathological examination after operation. AH data were analyzed by Excel statistic software.[Results] We found that Proto-oncogene c-met was expressed highly in laryngeal squamous-cell carcinomas (The rate was 65%).But the express rate was 10% In contrast .The differences were significant statistically(p<0.01).c-met was expressed in poorly ,moderately, and highly differentiated squamous-cell carcinomas at frequencies of 15,44,92% respectively. The differences were significant statistically (p<0.01).Similarly, we found there were relativity between the clinical stages, lymph nodes status of laryngeal squamous-cell carcinomas and c-met(p<0.01).But it was no relativity between patients'gender,neoplasms'places,sizes and c-met.[Conclusion] So we thought that proto-oncogene c-met expressed highly in laryngeal squamous-cell carcinomas,and it is relative to pathological differentiation,stage and lymph nodes status of laryngeal carcinomas.Postgraduate: Miao Beiping(ENT) Directed by: Professor Zhao shuyou...