Pattern of FHIT Gene 5'CpG Island Methylation Contribute to Human Cervical Carcinoma Cell Tumorigenesis

Objective 　To determine whether hypermethylation of FHIT played an important role in cervical tumorigenesis. Methods 　By incubating DNA in the presence of a methylase, we investigated the methylation of FHIT in four cervical cancer cell lines and one human umbilical vein endothelial cell line treating with the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (5-aza-dC) . The expression of FHIT was also monitored by RT-PCR and immunofluorescence technique before and af ter 5-aza-dC treatment . Results 　We found that methylation of FHIT occured in the four cervical cancer cell lines instead of the ECV-304. Through RT-PCR and immunofluorescence technique, we found that the expression of FHIT, which could hardly be detected in all four cervical cancer cells, was significant different af ter 5-aza-dC treatment . However, the ECV-304 cell expressed FHIT at constant levels before and af ter 5-aza-dC t reatment . Conclusion 　We concluded that hypermethylation of FHIT gene occurred f requently in cervical tumorigenesis. And hypermethylation within the regulatory sequences of FHIT gene might be an important means for its inactivation in cervical cancer.