[Mutation and abnormal expression of FHIT gene in hypopharyngeal carcinoma]

To analyze the mutation and abnormal expression of the FHIT gene in human hypopharyngeal carcinoma.

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.

Normal sized FHIT transcript was detected in 23 of the 24 cases of normal matched tissues. Aberrant FHIT transcripts were found in 9/24 (37.5%) cases in hypopharyngeal carcinoma. Aberrant FHIT transcripts rate of well-differentiated, moderately differentiated and poorly differentiated squamous cell carcinoma, was 28.6% (2/7), 50.0% (4/8) and 33.3% (3/9), respectively. There the carcinoma with FHIT aberrant transcripts was neither corresponding to histological grade (P>0.05) nor to lymphatic metastasis. The sequence analyses of the two aberrant cDNAs revealed absence of exon 8 and exon 7-9. All initial deletion were in conjunction of exons.

High deletion rate of the FHIT gene in Chinese hypopharyngeal squamous cell carcinoma suggested the FHIT gene, a candidate tumor suppressor gene at 3p14.2, plays an important role in the tumor carcinogenesis, development and progression of the tumor, and thus may become a new prognostic marker in hypopharyngeal carcinoma.