ABSTRACT
Fragile histidine triad (FHIT) gene is an important tumor suppressor gene,in non-small-cell lung cancer and precancerous lesions its protein deficiency is common,reflecting the FHIT gene is changing in lung cancer occurred in the early molecular events.Ferredoxin in the participation of Fhit protein promotes the electron transport function,and promotes the apoptosis of tumour cells in oxidative stress environment.Fhit protein expression combined platinum enhanced the apoptosis of tumor cell response.With early occuring,high-frequency and facilitate detection,the abnormal changes of FHIT/FRA3B,which take great significance to explain the factors,such as race,genetic polymorphism,geography,environment,respiratory diseases in the pathogenesis of lung cancer.
ABSTRACT
OBJECTIVE: The abnormal expression of fragile histidine triad (FHIT) gene has been frequently reported in a variety of epithelial malignancies including cervical carcinoma. Furthermore, in a recent study it was proposed that transcriptional inactivation of FHIT, as a consequence of aberrant 5'-CpG island methylation, plays an important role in the carcinogenesis of human cervical carcinoma. The authors sought to determine whether abnormal FHIT transcription occurs in human cervical carcinoma, and if so, whether this abnormal expression is associated with aberrant 5'-CpG island methylation. In addition, the clinical significance of FHIT inactivation was investigated in Korean women with cervical cancer. METHODS: To examine for abnormal transcripts of the FHIT gene, quantitative RT-PCR, genomic DNA-PCR and nonisotopic RT-PCR-SSCP analysis were performed using the standard method. The methylation status was determined by methylation specific PCR and bisulfite DNA sequencing. RESULTS: The FHIT gene was down-regulated in 15 of 58 (25.9%) cervical carcinomas. FHIT promoter hypermethylation was detected in 15 of 15 (100%) abnormally expression in cervical carcinomas. Bisulfite DNA sequencing confirmed these findings and a significant correlation was found between CpG site hypermethylation and low FHIT expression. However, no significant correlation was found between reduced FHIT expression and clinicopathological characteristics. CONCLUSION: In this study, FHIT inactivation in cervical cancer was found to be strongly correlated with 5'-CpG island hypermethylation rather than a genetic alteration. Furthermore, no significant relation was found between a lack of FHIT expression and the prognostic factors of cervical cancer in our Korean cohort.
Subject(s)
Female , Humans , Cohort Studies , Histidine , Methylation , Polymerase Chain Reaction , Sequence Analysis, DNA , Sulfites , Uterine Cervical NeoplasmsABSTRACT
Objective To investigate the effect of the exogenous fragile hisdidine triad(FHIT) gene on the proliferation and the apoptosis of cutaneous carcinoma cell line A431,and to explore the mechanism of tumor suppression by the FHIT gene.Methods The plasmids pcDNA3-FHIT and pcDNA3-vector were transfected into the cutaneous carcinoma cell line A431 without FHIT gene expression,and then the transfected cells were screened by G418 and the expression of FHIT was determined by the immunocytochemical staining technique.The effect of FHIT on the growth characteristics of cutaneous carcinoma cell line A431 was observed by MTT,colony forming test and flow cytometry.Results Stable FHIT gene expressing A431 cells were produced,the proliferation activity and colony forming capability of A431FHIT were suppressed,whereas the apoptosis was increased.All these differences between A431-FHIT cells and the two control groups of cutaneous carcinoma cells had statistical significance.Conclusion Transfecting the exogenous FHIT gene into cutaneous carcinoma cells line A431can suppress the proliferation of tumor cells,and can also induce apoptosis and cell cycle arrest.
ABSTRACT
Objective To investigate the status of fragile histidine triad (FHIT) gene in human esophageal, gastric and colorectal carcinomas. Methods Ninety six samples of digestive tract cancer (including 21 esophageal carcinomas, 43 gastric carcinomas and 32 colorectal carcinomas) tissues and their adjacent non carcinoma tissues and 18 samples of normal tissue were examined by nested RT PCR for FHIT gene alteration. Results Aberrant transcripts were observed in 33.3% esophageal cancers, 51.7% gastric cancers and 31.3% colorectal cancers. In the adjacent esophageal,gastric and colorectal non carcinoma tissues the rate of aberrant transcripts were 4.8%,20.9% and 9.4%, respectively ( P
ABSTRACT
Objective To investigate the expression of fragile histid ine triad (FHIT)gene and its relationship with the proliferation and apoptosis of tumor cells in cutaneous malignant melanoma (CMM).Methods The expression o f FHIT gene and PCNA were detected by streptavidin peroxidase method with skin s pecimens taken from 57 primary cutaneous melanoma and 20 normal controls.Apopto sis of tumor cells was detected by terminal deoxynuclneotidyl transferase mediat ed dUTP nick end labeling (TUNEL).Results The expression level of FHIT protei n was significantly lower in CMM than that in the normal skin tissue (P
ABSTRACT
Objective To construct eukaryotic cell expression vector of human frangible histone triad (FHIT) gene. Methods A 456 bp cDNA fragment was amplified from the total RNA of normal human thyroid tissue by RT PCR method and cloned into plasmid pcDNA3. The cloned insert was identified by double digestion of the recombinant plasmid with restriction enzymes Kpn Ⅰ and Bst XⅠ and sequenced by Sanger dideoxy mediated chain termination. The expression of FHIT gene was detected by immunocytochemical methods. Results The results showed that the cDNA fragment included 456 bp entire coding region. The recombinant eukaryotic cell expression vector of pcDNA3 FHIT was constructed, and the sequence of the insert was identical to the published sequence. MM96L cells transfected with the pcDNA3 FHIT plasmid expressed high level of Fhit protein in cytoplasm. Conclusion The recombinant plasmid pcDNA3 FHIT can provide a strong molecular tool for the studies of neoplasm pathogenesis.