R. Maestro et al., CHROMOSOME 13Q DELETION MAPPING IN HEAD AND NECK SQUAMOUS-CELL CARCINOMAS - IDENTIFICATION OF 2 DISTINCT REGIONS OF PREFERENTIAL LOSS, Cancer research, 56(5), 1996, pp. 1146-1150
Head and neck squamous cell carcinomas show frequent cytogenetic alter
ations involving the long arm of chromosome 13, To define the extent o
f 13q deletions and to identify the minimal areas of chromosome loss,
48 primary squamous cell carcinomas of the head and neck were analyzed
for loss of heterozygosity using 11 different polymorphic loci, About
67% of the tumors displayed loss of genetic material at 13q, Most of
the cases showed loss of the entire long arm of the chromosome, Howeve
r, the presence of partial deletions in 10 cases provided evidence of
the existence of two preferential sites of chromosome loss at 13q32-te
r and 13q14.2-q14.3. The colocalization of the 13q14 minimal region of
deletion with the retinoblastoma (RB) gene, which has been proposed a
s an oncosuppressor in diverse tumor types, prompted us to verify the
involvement of this gene in the development of head and neck cancer, N
o significant variation in RB protein or RB mRNA expression was detect
ed, thus excluding a role for such a gene in the genesis of this type
of tumor, Taken together, our data suggest the existence of tno new tu
mor suppressor genes (one close to and one distal to RB), which play a
role in the development and/or progression of head and neck squamous
cell carcinomas.