Abstract:

Objective:The aim of this study was to investigate the relationship between loss of heterozygosity (LOH) on chromosome 9p and the pathogenesis of oral squamous cell carcinoma (OSCC).Methods: Atotal of 24 humanOSCC specimenswere analyzed for LOHon chromosome 9p using 8 microsatellite markers by means of polymerase chain reaction.Results: In 24 cases of OSCC, LOH on chromosome 9pwas identified in 10 of 24 cases (41167%) with at least one marker. The main LOHwere found on 9p21 at locus D9S171 (21105%) and D9S304 (10.00%). There were also a deletion on 9p22-23 at locus D9S168 (22122%) and D9S162 (15138%). However, there was no statistically significant correlation between LOH at these loci with such clinical pa- rameters as pathological types, tumor size and lymph-node metastasis. Microsatellite instability (MSI) is rare for any of the 8 markers in 24 OSCC, No MSI could observed using the common criteria for defining MSI-its detection in two or more markers. Conclusion: We found that high frequency of LOH occurred at 9p21-23 band. Their results indicate that more than one tumor suppressor genes at chromosome 9p21-23 region related to a subset of OSCC, while MSI might not be a crucial event.

Key words: oral squamous cell carcinoma, loss of heterozygosity, microsatellite instability, chromosome 9p