Absence of markers of betaretrovirus infection in human pulmonary adenocarcinoma.

A proportion of human pulmonary adenocarcinomas has been shown previously to express an antigen related to the Gag protein of a betaretrovirus, Jaagsiekte sheep retrovirus, that causes ovine pulmonary adenocarcinoma. To investigate further the hypothesis that a retrovirus might be present in human lung adenocarcinoma, we examined specimens from patients with lung cancer for evidence of retroviral infection by immunohistochemistry, reverse transcriptase-polymerase chain reaction, immunoblotting and cDNA library screening. Thirty-eight percent of the tumor samples analyzed were positive by immunohistochemistry for Gag-related antigen of Jaagsiekte sheep retrovirus.