Definition of a tumor suppressor gene locus on the short arm of chromosome 3 in squamous cell carcinoma of the head and neck by means of microsatellite markers.

BACKGROUND

Tumor suppressor genes are important in the development of head and neck cancer. Using microsatellite markers that map close to the region 3p24-pter, we determined the frequency of allele loss close to this site with a view to narrowing the search for a putative tumor suppressor gene involved in the development of squamous cell carcinoma of the head and neck, which may facilitate future positional cloning techniques.

DESIGN

Laboratory-based project with tumor and normal specimens subjected to molecular genetic analysis. Tumor-normal tissue DNA pairs were analyzed for allelic imbalance and microsatellite instability on chromosome 3p in the region 3p24-pter by the polymerase chain reaction and microsatellite markers D3S1304, D3S656, D3S1252, D3S1293, THRB, and D3S1266.

SETTING

Molecular genetics and oncology research laboratory.

PATIENTS

Paired tumor-normal DNA samples were obtained from 46 patients with tumors of the head and neck.

MAIN OUTCOME MEASURES

Detection of loss of heterozygosity and microsatellite instability on chromosome 3 in the region 3p24-p25.1.

RESULTS

We found loss of heterozygosity with at least one marker in 48% of informative cases and loss of heterozygosity or microsatellite instability in 57% of informative cases. The minimal region of loss was found in the region bounded by D3S656 and D31293.

CONCLUSION

A putative tumor suppressor gene in head and neck cancer lies between D3S656 and D3S1293 in the 3p25.1 region.