Defective DNA mismatch repair proteins fail to correct replication errors (RERs). These defects may lead to secondary, mutation of oncogenes and tumor suppressor genes. Microsatellite instability might be a marker of such replication errors. Eighteen rectal tumors were examined to evaluate genetic instability, in sporadic rectal cancer by PCR. RERs were observed in 27.8% of the cases. No significant difference was noticed between RER+ and RER- patients as far as prognosis, clinicopathological features and p53 gene mutation are concerned. The incidence of nm23 gene mutation was the only statistically significant difference between the 2 groups. Three patients with only one altered microsatellite showed advanced tumor and nm23 gene mutation. Two cases with 5 altered microsatellites and nm23 gene mutated are disease-free: in one of them the p53 gene was also mutated. Probably more than one altered microsatellite is necessary to protect from the effects of secondary mutations.
|Autori:||INDINNIMEO M; CICCHINI C; STAZI A; MINGAZZINI P; CALIGO MA; GHIMENTI C; BEVILACQUA G|
|Titolo:||Genetic instability, p53 and nm23 mutation and clinicopathological features in rectal carcinoma|
|Anno del prodotto:||1998|
|Appare nelle tipologie:||1.1 Articolo in rivista|