M. Miyaki et al., COEXISTENCE OF SOMATIC AND GERM-LINE MUTATIONS OF APC GENE IN DESMOIDTUMORS FROM PATIENTS WITH FAMILIAL ADENOMATOUS POLYPOSIS, Cancer research, 53(21), 1993, pp. 5079-5082
Desmoid tumors, which are locally invasive with recurrence but without
metastasis, are frequently observed in patients with familial adenoma
tous polyposis after abdominal surgery or during pregnancy. This study
analyzed mutation of the adenomatous polyposis coli gene in 8 desmoid
tumors from 7 familal adenomatous polyposis patients using polymerase
chain reaction-single-strand conformation polymorphism and the direct
sequencing method. Seven somatic mutations, 1 somatic allele loss, an
d 6 germ-line mutations were detected. The majority of adenomatous pol
yposis coli gene mutations were deletions of 1 to 19 base pairs in exo
n 15, and all mutations led to the formation of stop codons. A somatic
mutation with repetition of 82 base pairs from codon 1399 to 1426 was
also observed in a desmoid, which was most likely caused by an error
during replication or repair replication. No mutation was detected in
exons 1 to 2 of H-ras, K-ras, and N-ras genes and in exons 5 to 8 of p
53 gene, in these tumors. The simultaneous existence of somatic and ge
rm-line alterations of adenomatous polyposis coli gene observed in all
8 tumors strongly suggests that inactivation of both alleles of adeno
matous polyposis coli gene is involved in the development of desmoid t
umors.