Expression of TGF-beta and procollagen type I and type III in human gastric carcinomas.
To elucidate the difference between scirrhous and non-scirrhous gastric carcinomas, we examined the expressions of TGF-beta, procollagen type I and type III in 7 gastric carcinoma cell lines and 37 gastric carcinoma tissues, and also examined the effect of TGF-beta on the expression of procollagen mRNA by TMK-I cells. TGF-beta mRNA was detected in all the tumors examined in vivo and in vitro. Interestingly, 9 (90%) of 10 scirrhous gastric carcinomas revealed higher levels of TGF-beta mRNA than normal tissues, while 8 (38%) of 21 well-differentiated adenocarcinomas had higher TGF-beta mRNA levels than normal tissues. As for procollagen mRNA, most of the human gastric carcinoma cell lines expressed type-I procollagen mRNA and MKN-I expressed type-III procollagen mRNA. Furthermore, procollagen type-I mRNA accumulation in TMK-I cells was increased by exogenous TGF-beta. Most of the tumor tissues from surgical specimens expressed higher procollagen mRNA than normal tissues. These results indicate that TGF-beta produced by carcinoma cells might stimulate collagen synthesis not only by fibroblasts but also by carcinoma cells themselves, leading to diffuse fibrosis of scirrhous gastric carcinomas.
First Department of Pathology, Hiroshima University School of Medicine, Japan.
K
K
Yoshida
H
H
Yokozaki
M
M
Niimoto
H
H
Ito
M
M
Ito
E
E
Tahara
D002277:Carcinoma / Q000378:metabolism*; D006801:Humans; D011347:Procollagen / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis*; D013274:Stomach Neoplasms / Q000378:metabolism*; D015291:Transforming Growth Factors / Q000235:genetics* / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D011347:Procollagen; D012333:RNA, Messenger; D015291:Transforming Growth Factors