Frequent amplification of the cyclin E gene in human gastric carcinomas.
We searched for genetic alterations of the cyclin D1 and cyclin E genes in 45 human gastric carcinoma tissues. Expression of cyclin E mRNA and protein was also analyzed in eight of them by Northern and Western blots and immunohistochemical staining. The cyclin E gene was amplified 3-10 fold in seven gastric cancer tissues (15.6%), of which six were advanced gastric cancers. All of the cases with the cyclin E gene amplification displayed lymph node metastasis. Moreover, the case with the gene amplification overexpressed the cyclin E mRNA and protein. One of eight gastric cancer cell lines, MKN-7, shared the cyclin E gene amplification, and all of the gastric cancer cell lines expressed high levels of the cyclin E mRNA and protein even without gene amplification. Amplification of the cyclin D1 gene was not observed in any of the gastric carcinoma tissues or gastric carcinoma cell lines. These results suggest that the gene amplification and overexpression of cyclin E play an important role in the abnormal growth and progression of gastric carcinoma.
Akama
Y
Y
First Department of Pathology, Hiroshima University School of Medicine.
Yasui
W
W
Yokozaki
H
H
Kuniyasu
H
H
Kitahara
K
K
Ishikawa
T
T
Tahara
E
E
D000368:Aged; D015152:Blotting, Northern; D015153:Blotting, Western; D002460:Cell Line; D019938:Cyclin D1; D016213:Cyclins / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D005784:Gene Amplification; D015870:Gene Expression; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D015513:Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D014407:Tumor Cells, Cultured
D016213:Cyclins; D015513:Oncogene Proteins; D012333:RNA, Messenger; D019938:Cyclin D1