Study On The Protein Expression Of HPV16 And Its Early Gene E6/E7 And Rb Proteins In Human Laryngeal Squamous Cell Carcinoma And Their Relationship

[Objective]Laryngeal carcinoma is a commonly malignant tumor in otolaryngology, whose incidence inclines to go higher recently, but whose pathogenesis is unknown. Many researched indicated that laryngeal carcinoma is often the result of a long-term exposure to a variety of carcinogens including tobacco, ethanol, et al. At present, human papillomavirus (HPV) has been identified to be correlated with laryngeal carcinoma closely, and our former study has also found that HPV16 is associated with laryngeal carcinoma.In order to Observing the correlation of expression rate of HPV 16 protein and its early gene HPV16 E6/E7 expressed proteins and retinoblastoma (Rb) protein in human laryngeal squamous cell carcinoma so that we can give gists for the etiology search and immunologic therapy of laryngeal carcinoma. The expressions rate of HPV16,HPV16 E6,HPV16 E7 and Rb proteins were detected by the immunohistochemical method in the specimens with different clinical stages and different histopathological grades laryngeal squamous cell carcinoma and the specimens with non-carcinoma so far as to probe into their relationship with the genesis of human laryngeal carcinoma, further study the mechanism of the genesis, and supply the molecule biological evidence and new method of earlier diagnosis, prevention and cure of laryngeal carcinoma.[Methods]The 147 specimens of different laryngeal tissues sample were collected by surgery in our department from 1999. Of which, there were 82 specimens of laryngeal carcinoma, 53 specimens of non-carcinoma of larynx (including 27 specimens of polyp of vocal cord, 26 specimens of leukoplakia of the larynx), and 12 specimens of normal laryngeal tissues taken from the area more than 1.5 cm adjacent to the carcinoma.In 82 cases with laryngeal carcinoma, there were 80 males and 2 females, whose average age was 60.55±10.65 years (age ranges from 38 to 85 years). Tumor clinical stages showed 13 cases in clinical stageⅠ, 17 cases in clinical stageⅡ, 30 cases in clinical stageⅢand 22 cases in clinical stageⅣ, according to the criteria of the 2002 Union International Conte le Cancer. Tumor grading showed 22 cases in histopathological gradeⅠ(well differentiated), 32 cases in gradeⅡ(moderately differentiated), and 28 cases in gradeⅢ(poorly differentiated). All of the patients in this study had not been treated with radiation or chemical therapy before the operation.All specimens were fixed in a 10% neutral buffered formalin solution, underwent tissue processing, and were embedded in paraffin. The expressions of HPV16,HPV16 E6,HPV16 E7 and Rb proteins were detected by the immunohistochemical method of EnVision kit.[Results]1,Between different human laryngeal tissues, different clinical stages and different histopathological grades of laryngeal cacinoma, there were difference for the positive expression rates of HPV16(P<0.05).2,Between different human laryngeal tissues, there were difference significantly for the positive expression rates of HPV16 E6 and HPV16 E7(P<0.01),while in different clinical stages and different histopathological grades, there were no difference statistically (P>0.05).3,Between non-carcinoma and laryngeal squamous cell carcinoma tissues, there were different positive expression rates for the HPV16 E6/E7 and Rb proteins(P<0.01);Between the positive expression rates of the expression of HPV16 E6/E7 and Rb proteins, there were negative correlation significantly in non-carcinoma tissues(P<0.01).4,Between non-carcinoma and laryngeal squamous cell carcinoma tissues, there were different positive expression rates for the HPV16 E7 and Rb proteins(P<0.01)and for HPV16(P<0.05).5,In laryngeal squamous cell carcinoma tissues, there were different positive rates of Rb protein in HPV16(+) and HPV16(-) group or HPV16 E7(+) and HPV16 E7(-) group(P<0.01);comparing non-carcinoma tissues, there were no such difference(P>0.05).6,In laryngeal squamous cell carcinoma tissues, there were different positive rates of Rb protein in HPV16 E7(+) and HPV16 E7(-) group(P<0.01);comparing HPV16 E6(+) and HPV16 E6(-) group or non-carcinoma tissues, there were no such difference(P>0.05).[Conclusion]1,The occurring of human laryngeal carcinoma might be related to the expression of HPV16 E6,E7 proteins after the HPV16 infection;2,The expression of HPV16 E6 and E7 proteins might not be the factors to induce the different clinical stages of human laryngeal carcinoma;3,The expression of HPV16 E6 and E7 proteins might not be the factors to induce the different histopathological grades of human laryngeal carcinoma;4,The over expression of HPV16 E7 protein in human laryngeal carcinoma might be the main factor for the inactivation of Rb protein.5,It might be of one the main factors for the human laryngeal carcinoma occurrence that inactivation of Rb protein caused by over expression of HPV16E7 protein.6,It is useful to treat human laryngeal carcinoma by means of restraining the expression of E7 protein via immunologic therapy, but its prevent and therapy function shouldn't be too aggrandized.