[Cloning of 67 kDa-laminin receptor cDNA and its expression in various human lung cancer cell lines].

Cell-adhesive proteins such as laminin and fibronectin and their specific receptors play an important role in the processes of cancer proliferation, invasion, and metastasis. In the present study, we cloned the cDNA of 67 kDa-laminin receptor both from human lung cultured cell line (IMR90) and from human small cell lung cancer (SBC3), and determined the nucleotide sequences. In addition, the expression of mRNA in 11 lung cancer cell lines with various cell types was estimated by the method of Northern blot hybridization. As a result, 1.2 kb-message was detected in all cancer cell lines examined. It was also demonstrated that the mRNA level of 67 kDa-laminin receptor was inversely proportional to the population doubling time of the cell line (r = -0.80).