2698
This study demonstrates a novel link between alterations in platelet - derived growth factor ( PDGF ) regulation of ornithine decarboxylase ( ODC ) expression during malignant conversion .
 GENE: platelet - derived growth factor; GENE: PDGF; GENE: ornithine decarboxylase; GENE: ODC
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 GENE: platelet - derived growth factor; GENE: PDGF; GENE: ornithine decarboxylase; GENE: ODC