PDGFA and PDGFRA expression was evaluated by immunohistochemistry in a series of 160 gliomas of distinct World Health Organization (WHO) malignancy grade.
Overexpression of platelet-derived growth factor A-chain (PDGF-A) is clearly linked to autocrine and paracrine stimulation of malignant growth in many human cancers.
Of the 15 explants tested, PDGFB was seen in six, all of which were malignant tumors; PDGFA was seen in all 15 with much higher levels expressed in malignant tumors; and TGF-beta 1 and TGF-beta 2 were seen in all 15 without a clear difference between cell types, although expression tended to be higher in malignant tumors.
These results suggest that malignant mesothelioma cell lines show constitutively enhanced expression of the c-sis and PDGF A-chain genes that could play a role in the etiology of this type of malignancy.