Abstract: Objective: To study tumor suppressor gene——fragile histidine triad（FHIT）， human papillomavirus16E6（HPV16E6） expression and their significance in cervical squamous carcinomas（CSC）. To study the correlation between FHIT， HPV16E6 in CSC. Methods: Immunohistochemical staining for FHIT， HPV16E6 were performed by SP methods in 40 cases of CSC， 30 cases of cervical intraepithelial neoplasias（CIN）， and 30 cases of normal cervical epithelium. Results: The express of FHIT in 96.7% of normal cervical epithelium， 66.7% of CIN and 30.0% of the CSC， FHIT expression showed significant statistical difference（χ2=43.595， P＜0.001）. The expression of FHIT in the degree of differentiation and clinic stages of CSC indicates no statistical difference （χ2=3.378， χ2=3.315， P＞0.05）. The expression of HPV16E6 in 13.3% of normal cervical epithelium， 53.3% of CINs， and 82.5% of the CSC， HPV16E6 expression showed significant statistical difference（χ2=32.538， P＜0.001）. The expression of HPV16E6 in the degree of differentiation and clinic stages of CSC were observed no statistical difference （χ2=0.231， χ2=1.399， P＞0.05）. Conclusions: The FHIT gene expression deletion and the high detection rate of HPV16E6 in the CSC indicate that these two factors play an important role in the CSC development mechanism. The infection of HPV16-E6 and the FHIT gene deletion might be the one of the CSC pathogenesises（or might be the causes of CSC）. The results of this study that FHIT gene and HPV16E6 biological effects on CSC development and their interaction in CSC could help reveal the pathogenesis of CSC. These two factors could be the potential CSC clinical diagnosis indicator and useful in CSC precaution and gene therapy.

Key words: Uterine cervical neoplasms, Human papillomavirus 16, Genes, tumor suppressor, Immunohistochemistry, FHIT gene