Absence of mutations in the transforming growth factor-beta type II receptor in sporadic lung cancers with microsatellite instability and rare H-ras1 alleles

The transforming growth factor-beta type II receptor (RII) is commonlymutated in colon and gastric cancers with microsatellite instability (MI).We utilized our series of lung cancers with MI and rare alleles of theH-ras1 gene to determine the association between MI and RII mutations andsearched the entire RII coding region in 33 lung cancers with MI bypolymerase chain reaction-single-strand conformation polymorphism analysis.We found no mutations, and these data support other recent evidence thatRII mutations rarely occur except in colon and gastric tumors with MI.