Expression of the E2F family in human gastrointestinal carcinomas.
The E2F family of transcription factors plays a key role in the control of cell-cycle progression. Some family members may act as oncogenes, others as tumor-suppressor genes. The genetic changes and the expression of E2F-1 and -3 were examined in human gastric and colorectal carcinomas by Southern, Northern and Western blots. Gene amplification of E2F-1 was detected in 4% (1/23) of gastric carcinomas and 25% (3/12) of the colorectal carcinomas. Increased expression of E2F-1 mRNA was observed in 40% (12/30) of the gastric carcinomas and in 60% (3/5) of the colorectal carcinomas in comparison with the corresponding non-neoplastic mucosa. Over-expression of E2F-1 protein was confirmed in many of the gastric carcinomas. In contrast, expression levels of E2F-3 mRNA were lower in 70% (21/30) of the gastric carcinomas and in 20% (1/5) of the colorectal carcinomas than in their corresponding normal counterparts, while gross alteration of the E2F-3 gene was not detected. These results suggest that gene amplification and anomalous expression of the E2F gene may permit development of gastrointestinal carcinomas.
Suzuki
T
T
First Department of Pathology, Hiroshima University School of Medicine, Japan.
Yasui
W
W
Yokozaki
H
H
Naka
K
K
Ishikawa
T
T
Tahara
E
E
D000328:Adult; D000368:Aged; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D004268:DNA-Binding Proteins / Q000235:genetics; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; D050699:E2F3 Transcription Factor; D005260:Female; D005784:Gene Amplification; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D056465:Retinoblastoma-Binding Protein 1; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology; D050680:Transcription Factor DP1; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; D050699:E2F3 Transcription Factor; C098319:E2F3 protein, human; D012333:RNA, Messenger; D056465:Retinoblastoma-Binding Protein 1; D050680:Transcription Factor DP1; D014157:Transcription Factors