Coexpression of platelet-derived growth factor (PDGF) A-chain and PDGF receptor genes in human gastric carcinomas

In this study we examined the expression of platelet-derived growth factor (PDGF) A-chain and PDGF receptor genes in seven human gastric carcinoma cell lines and 15 gastric carcinoma tissues. Expression of mRNA for PDGF A-chain was found in all gastric cell lines and all gastric carcinoma tissues. Two of the seven gastric carcinoma cell lines expressed PDGF receptor mRNA. Out of the 15 gastric carcinoma tissues, eight showed enhanced expression of PDGF receptor mRNA and all of them demonstrated prominent fibrous stroma. Moreover, the incidence of enhanced expression of PDGF receptor mRNA was higher in scirrhous carcinoma than in well differentiated adenocarcinoma. These results strongly suggest that PDGF produced by tumor cells acts as a paracrine growth factor for production of fibrous stroma in gastric carcinomas.