RESUMO
We have shown that melanoma cells produce viral particles that contain sequences which are homologous to human endogenous retroviruses. In this study particles derived from different melanoma cell lines and from melanoma cells of a lymph node metastasis were characterized. We determined the density and the reverse transcriptase (RT) activity of viral particles. Furthermore, we analyzed the sequence variability of multiple clones of each particle preparation. The particles were found to package sequences, which vary for each of the analyzed cell lines. Moreover, even particles derived from the same cell line contain heterologous sequences.
Assuntos
Retrovirus Endógenos/genética , Variação Genética , Genoma Viral , Melanoma/virologia , Idoso , Sequência de Bases , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Humanos , Linfonodos/virologia , Metástase Linfática , Melanoma/secundário , Dados de Sequência Molecular , Alinhamento de SequênciaRESUMO
We show that human melanoma cells produce retrovirus-like particles that exhibit reverse transcriptase activity, package sequences homologous to human endogenous retrovirus K (HERV-K), and contain mature forms of the Gag and Env proteins. We also demonstrate expression of the pol gene and of Gag, Env, and Rec proteins in human melanomas and metastases but not in melanocytes or normal lymph nodes. The data suggest that expression of retroviral genes and production of retroviral particles is activated during development of melanoma.