Data/hora: 10/06/2024 10:05:57

Provedor de dados: | 56
País: | Brazil
Título: | Collateral methotrexate resistance in cisplatin-selected murine leukemia cells
Autores: | Bhushan,A.; Hacker,M.P.; Tritton,T.R.
Data: | 1999-07-01
Ano: | 1999
Palavras-chave: | Methotrexate transport; Resistance; Cisplatin; Leukemia; Phosphorylation.
Resumo: | Resistance to anticancer drugs is a major cause of failure of many therapeutic protocols. A variety of mechanisms have been proposed to explain this phenomenon. The exact mechanism depends upon the drug of interest as well as the tumor type treated. While studying a cell line selected for its resistance to cisplatin we noted that the cells expressed a &amp;gt;25,000-fold collateral resistance to methotrexate. Given the magnitude of this resistance we elected to investigate this intriguing collateral resistance. From a series of investigations we have identified an alteration in a membrane protein of the resistant cell as compared to the sensitive cells that could be the primary mechanism of resistance. Our studies reviewed here indicate decreased tyrosine phosphorylation of a protein (molecular mass = 66) in the resistant cells, which results in little or no transfer of methotrexate from the medium into the cell. Since this is a relatively novel function for tyrosine phosphorylation, this information may provide insight into possible pharmacological approaches to modify therapeutic regimens by analyzing the status of this protein in tumor samples for a better survival of the cancer patients.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000700005
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X1999000700005
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.32 n.7 1999
Fonte: | info:eu-repo/semantics/openAccess