| [Objective]The research programme was supported by National Natural Science Funds of China under the Grant No.30371610.Laryngeal carcinoma is a commonly malignant tumor in otolaryngology, whose incidence inclines to go higher recently, but whose pathogenesis is unknown. 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 has been identified to be correlated with laryngeal carcinoma closely, and our study has found that HPV16 is associated with laryngeal carcinoma. To study the expressions of heat shock protein 70, retinoblastoma proteins and human papillomavirus 16E7 proteins in human laryngeal carcinoma and 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, we detect the expressions of HSP70, Rb proteins and HPV16E7 proteins in different histopathological grade and Clinical stage of human laryngeal carcinoma and in precarcinoma of larynx.[Methods]The 138 specimens of different laryngeal tissues sample were collected by surgery in our department between Jan. 1996 and Jun. 2003. There were 78 specimens of laryngeal carcinoma, 26 specimens of precarcinoma of larynx (including 15 specimens of chronic hyperrophic laryngitis, 11 specimens of laryngeal leukoplakia), 24 specimens of vocal cord polyps and 10 specimens of normal laryngeal tissues taken from the area more than 1.0 cm adjacent to the carcinoma. In 78 cases with laryngeal carcinoma, there were 23 males and55 females, whose average age was 61.5 years (age ranges from 44 to 79 years). Tumor clinical stages showed 14 cases in clinical stage 1,13 cases in clinical stage II, 25 cases in clinical stagelll and 26 cases in clinical stage IV, according to the criteria of the 1987 Union International Conte le Cancer. Tumor grading showed 21 cases in histopathological grade I (well differentiated), 30 cases in grade II (moderately differentiated), and 27 cases in gradeIII(poorly differentiated). All specimens were fixed in a 10% neutral buffered formalin solution, underwent tissue processing, and were embedded in paraffin. The expressions of HSP70, Rb proteins and HPV16E7 proteins were detected by the immunohistochemical method of EnVision kit.[Results]In normal laryngeal tissues, vocal cord polyps, precarcinoma of larynx and laryngeal carcinoma, the positive expression rates of HPV16E7 protein were 0% (0/10), 4.1% (1/24), 27.0% (7/26) and 43.6% (34/78) respectively, those of Rb protein were 80.0% (8/10), 79.2% (19/24), 61.5 %(16/26) and 50.0% (39/78) respectively, and those of HSP70 were 0% (0/10), 8.3% (2/24), 50.0% (13/26) and 69.2% (54/78) respectively. In histopathological grade I, grade II and gradelllof laryngeal carcinoma, the positive expression rates of HPV16E7 protein were 28.6%(6/21), 36.7% (11/30)and 63.0% (17/27) respectively, those ofRb protein were 71.4% (15/21), 56.7% (17/30)and 25.9% (7/27) respectively, and those of HSP70 were 52.3% (11/21), 63.3% (19/30) and 88.9% (24/27) respectively. In clinical stage I - II and stage III-IV of laryngeal carcinoma, the positive expression rates of HPV16E7 protein were 26.0% (14/17) and 52.9% (27/51) respectively, those of Rb protein were 74.1% (20/27) and 37.3% (19/51) respectively, and those of HSP70 were 51.8% (14/27) and 78.4% (40/51) respectively. There was a significant difference of the expression rate of HPV16E7 protein and Rb protein between the laryngeal carcinoma and the vocal cord polyps(P<0.05). The positive expression of HPV16E7 protein was increased gradually, while that of Rbprotein was reduced gradually. In laryngeal carcinoma the positive expression rate of HPV16E7 protein in histopathological gradelllwas significantly higher than that in histopathological grade I or grade II (P<0.05), in the same way the positive expression rate of HPV16E7 protein in clinical stage III-IV was significantly higher than that in clinical stage I - II (P<0.05).On the contrary, the positive expression rate of Rb protein in histopathological grade III was significantly lower than that in histopathological grade I or grade II (P<0.05), and the positive expression of Rb protein in clinical stagelll-IV was significantly lower than that in clinical stage I -II (P<0.05). There was a significant difference of the expression rate of HSP70 between the laryngeal carcinoma and the vocal cord polyps (P<0.05). The positive expression of HSP70 in laryngeal carcinoma was significantly higher than that in the vocal cord polyps. In laryngeal carcinoma the positive expression rate of HSP70 in histopathological grade III was significantly higher than that in histopathological grade I or grade II (P<0.05), in the same way the positive expression rate of HSP70 in clinical stage III- IV was significantly higher than that in clinical stage I -II (P<0.05). There was a significant difference of the expression rate of HSP70 between the laryngeal carcinoma with positive expression of HPV16E7 protein and that with negative expression of HPV16E7 protein (P<0.05), whose positive expression rates were 85.3% (29/34) and 56.8% (25/44) respectively. The positive expression of HSP70 in laryngeal carcinoma with positive expression of HPV16E7 protein was significantly higher than that with negative expression of HPV16E7 protein.[Conclusion]Overexpression of HPV16E7 protein and loss of Rb protein expression may contribute to the genesis of human laryngeal carcinoma. The overexpression of HSP70 can be induced by HPV16E7 protein, which may contribute to the genesis of human laryngeal carcinoma. Detection of the expressions of HSP70, HPV16E7 and Rb proteins may be useful in evaluation of the aggressivenessof human laryngeal carcinoma.
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