Furthermore, staining for PDGFR-β was seen in many pericytes in PDGF-B overexpressing carcinomas, implying that PDGF-B produced by cancer cells caused increased pericyte coverage around vessels, whereas faint staining was also seen in pericytes of carcinomas without PDGF-B overexpression (Figure 2). This evidence concerns the gene PDGFB and cancer.