Cloning of 67-kDa laminin receptor cDNA and gene expression in normal and malignant cell lines of the human lung.

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.