RESUMO
Cell-adhesive protein laminin and its specific receptor play an important role in the processes of cancer proliferation, invasion and metastasis. In the present study, we cloned the cDNAs of the 67-kDa laminin receptor both from a human lung cell line (IMR90) and from a human lung cancer cell line (SBC3), and determined the nucleotide sequences. In comparison with both cDNA sequences of the protein-coding region, three nucleotide differences were found. These differences in the secondary structure of the protein, however, were caused by nucleotide substitutions. It was also demonstrated that the level of 67-kDa-laminin receptor mRNA was higher in SBC3 than in IMR90.
Assuntos
DNA/química , Neoplasias Pulmonares/metabolismo , Receptores Imunológicos/biossíntese , Proteínas Recombinantes/biossíntese , Sequência de Aminoácidos , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Expressão Gênica , Humanos , Pulmão/metabolismo , Dados de Sequência Molecular , RNA Mensageiro/análise , Receptores Imunológicos/genética , Receptores de LamininaRESUMO
We investigated the expression of laminin in two cell lines with different metastatic potentials established from murine Lewis lung carcinoma. Immunostaining of the cells with anti-laminin antibody and Northern blot analysis of laminin mRNA demonstrated that the high metastatic clone expressed less laminin than the low metastatic one. In contrast, expressions of 67 kDa-laminin receptor were at similar levels between these two lines. These findings show the possibility that endogenous laminin may contribute to the difference in metastatic properties in the murine Lewis lung carcinoma cell lines examined.