Fhit expression is absent or reduced in a subset of primary head and neck cancer.

BACKGROUND

The inactivation of the FHIT gene at 3p14.2 by various mechanisms might be of importance in head and neck squamous cell carcinoma (HNSCC). Most reports are based on DNA and RNA findings of intragenic deletions and abnormal transcripts.

MATERIAL AND METHODS

To study the protein expression of this putative tumour suppressor gene, we analysed 48 HNSCCs by immunohistochemistry using a polyclonal antibody (ZR44). The results were compared with mutation analysis, clinical data and loss of heterozygosity (LOH) data at 3p14.2.

RESULTS

Complete absence of Fhit expression was detected in 8 out of 48 of tumours (17%) and 3 tumours (6%) showed heterogenous staining. The overall frequency of LOH for microsatellite D3S1234 was 64% and 5/7 of Fhit negative tumours exhibited LOH.

CONCLUSION

Our findings provide further evidence that FHIT is inactivated in a subtype of HNSCC; however, the incidence of lack of Fhit expression compared to the high frequency of LOH on chromosome 3p supports the notion of additional tumour suppressor genes at 3p14.