Similarity between glyceraldehyde-3-phosphate dehydrogenase and a 37,000-dalton protein which is abundantly expressed in human lung cancers.

Human lung cancers of all histological types contain a protein of 37,000 daltons (37K) as an abundant component. Partial sequence analysis of purified 37K revealed a strong homology with glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12). Tryptic peptide mapping analysis showed that the pattern of 37K was very similar to those of GAPDHs both purified from lung tumor and obtained commercially. An antibody raised against 37K in a rabbit also reacted with authentic GAPDH. These results suggest a possible involvement of GAPDH itself or a GAPDH-related protein in lung tumorigenesis.