Objective: To analyze the mutation and abnormal expression of the FHIT gene in human hypopharyngeal carcinoma.
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.
Result: 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.
Conclusion: 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.