Fhit Gene And Related Studies Of Hypopharyngeal And Pectoralis Major Myocutaneous Flap In The Department Of Otolaryngology - Head And Neck Surgical Oncology Defect

Objective: To analyze the expression of fragile histidine triad gene protein—FHIT and the transcript abnormal of FHIT Gene in human hypopharyngeal carcinoma. To explore the relationship between FHIT gene and hypopharyngeal carcinoma.Methods: Detecting FHIT protein in 60 cases of formalin-fixed,paraffin-embeded hypopharyngeal squamous cell carcinoma and analysing its relationship to historical grade and lymphatic metastasis were performed by rabbit antibody to human FHIT gene protein with citrate-microwave-SP irnmunohistochemical method. Matched normal and cancerous tissues from 24 patients with hypopharyngeal squamous cell carcinoma were obtained immediately after surgery. Total RNA was extracted, the FHIT gene was detected by nested RT-PCR and DNA sequencing technology.Results: FHIT expression was detected positive in 45%(27/60) cases of carcinoma, and 88.3% (53/60) in nomal hypopharyngeal tissure, respectively. There was a significant difference in FHIT expression between the cancer tissure and nomal tissure(P=0.000). The expression of FHIT in hypopharyngeal carcinoma wascorresponding to histoiogical grade (P=0.0277) due to well cell differentiation in 62.5%(15/24), morderate cell differentiation in 36.8%(7/19) and poor in 29.4%(5/17). The carcinoma's expression of FHIT was corresponding to lymphatic metastasis (P=0.02) due to with lymphatic metastasis in 37.5%( 18/48), without lymphatic metastasis in 75%(9/12). Normal sized FHIT transcript was detected in 23 of the 24 cases of normal matched tissures. Aberrant transcripts were observed in 37.5%(9/24) cases in hypopharyngeal carcinoma. The carcinoma with FHIT aberrant transcripts was neither corresponding to histoiogical grade (P=0.9268) nor to lymphatic matastasis (P= 1.0000). The sequence analyses of the two aberrant cDNAs revealed absence of exon 8 and exon 7~9.Conclutions: High deletion rate of the FHIT gene in Chinese hypopharyngeal squamous cell carcinoma suggested the FHIT gene, a candidate tumor suppressor gene at 3pl4.2, plays an important rule in the tumor origenesis, development and progression of the tumor, and thus may become a new prognostic marker in hypopharyngeal carcinoma.