Failure to Detect Mutations in the Retinoblastoma Protein‐binding Domain of the Transcription Factor E2F‐1 in Human Cancers

The functions of the transcription factor E2F‐1 are regulated by the RB protein through the RB‐binding domain of E2F‐1 and this factor is considered to be an important molecule that functions downstream of the RB protein. In order to determine whether E2F‐1 that cannot bind to RB might be associated with various human cancers, we searched for mutations in the RB‐binding domain of E2F‐1 using samples of DNA from various clinical specimens obtained from 406 cancer patients (with lung, pancreatic, stomach, colon, esophageal, and hepatic cancers) by analysis of polymerase chain reaction‐mediated single‐strand conformational polymorphism. No mutations or deletions were detected in genes for E2F‐1 from any of the tumor tissues examined. These results suggest that a mutation or deletion in E2F‐1 that might affect binding of the RB protein is not involved in human cancers.