Detection of c-sis transcripts and PDGF-like products by in situ hybridization and immunohistochemical study

To clarify the relationship between oncogene c-sis expression and tumorigenesis in human osteosarcoma, in situ hybridization and immunohistochemical studies were performed to detect c-sis mRNA and PDGF-like protein partially consisting of c-sis product. Formalin fixed-paraffin embedded sections of eight cases of osteosarcoma of bone were examined. Three osteosarcomas highly expressed c-sis mRNA with a fine granular pattern in their cytoplasms. Five osteosarcomas, including three cases with c-sis expression, contained PDGF-like protein in their cytoplasms. These results suggested that c-sis oncogene and PDGF-like protein were closely related to tumorigenesis in human osteosarcoma. The DNA-mRNA in situ hybridization technique applied by the author is as efficient as the immunohistochemical method in cancer research.