Human malignant mesothelioma cell lines express PDGF beta-receptors whereas cultured normal mesothelial cells express predominantly PDGF alpha-receptors.
In human malignant mesothelioma cell lines elevated expression of the platelet-derived growth factor (PDGF) beta-chain (c-sis) gene was previously reported, while normal mesothelial cells barely express this gene. Expression of the PDGF A-chain gene was only slightly elevated in these cell lines compared with normal mesothelial cells. For a putative autocrine function of the produced PDGF, in these cells expression of PDGF receptors is a prerequisite. In this paper we report on the expression of PDGF alpha- and beta-receptors in normal and malignant mesothelial cells. Cultured normal mesothelial cells expressed PDGF alpha-receptor mRNA and protein and had weak to undetectable levels of the PDGF beta-receptor mRNA and protein. In contrast, malignant mesothelioma cell lines were found to express PDGF beta-receptor mRNA and protein, while PDGF alpha-receptor expression was not detectable by Northern blotting and immunoprecipitation. Binding experiments with [125I]-PDGF-AA and [125I] PDGF-BB to normal and malignant mesothelial cell lines confirmed these observations. These results suggest that autocrine stimulation of growth may occur both in cultured normal mesothelial cells (PDGF-AA acting via the alpha-receptor) and in malignant mesothelioma cell lines (PDGF-BB acting via the beta-receptor).
Versnel
M A
MA
Department of Immunology, Erasmus University, Rotterdam, The Netherlands.
Claesson-Welsh
L
L
Hammacher
A
A
Bouts
M J
MJ
van der Kwast
T H
TH
Eriksson
A
A
Willemsen
R
R
Weima
S M
SM
Hoogsteden
H C
HC
Hagemeijer
A
A
D015152:Blotting, Northern; D002460:Cell Line; D002894:Chromosomes, Human, Pair 4; D002895:Chromosomes, Human, Pair 5; D004848:Epithelium / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D008654:Mesothelioma / Q000235:genetics / Q000378:metabolism*; D016253:Microscopy, Immunoelectron; D011233:Precipitin Tests; D012333:RNA, Messenger / Q000096:biosynthesis; D011869:Radioligand Assay; D011956:Receptors, Cell Surface / Q000096:biosynthesis*; D017479:Receptors, Platelet-Derived Growth Factor
D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D017479:Receptors, Platelet-Derived Growth Factor