Y. Fujiwara et al., PTEN/MMAC1 mutation and frequent loss of heterozygosity identified in chromosome 10q in a subset of hepatocellular carcinomas, JPN J CANC, 91(3), 2000, pp. 287-292
Frequent allelic losses on chromosome 10q have been reported in several typ
es of cancers, suggesting the presence of a putative tumor suppressor gene(
s) on the chromosomal arm. We examined loss of heterozygosity (LOH) on chro
mosome 10q in 37 hepatocellular carcinomas (HCC) using eleven dinucleotide
microsatellite markers, spanning the entire chromosome arm of 10q, Twelve (
32%) out of 37 informative cases showed allelic losses of at least one locu
s on 10q and eight tumors showed a partial deletion of 10q, Analysis of del
etion mapping of these eight cases identified two commonly deleted regions
within the distal part of 10q (10q24-q26), a 20-cM interval flanked by D10S
597 and D10S216 and a 24-cM interval flanked by D10S216 and D10S590, Moreov
er, we detected a somatic missense mutation (Met-->Val) of a candidate tumo
r suppressor gene PTEN/MMAC1, located at 10q23.3, in one HCC with LOH of 10
q. Our findings indicated the presence of putative tumor suppressor gene(s)
in the distal region of 10q that might be involved in the development and
progression of HCC. Inactivation of PTEN/MMAC1 gene located outside the com
monly deleted region of 10q might also play an important role in a subset o
f HCCs.