Cleft Lip And Palate Associated Transmembrane Protein 1 Like Protein (CLPTM1L)

Using differential display to identify genes involved in resistance to the anticancer drug cisplatin in ovarian cancer cell lines, followed by 5-prime RACE of the cisplatin-resistant cell line, Yamamoto et al. (2001) cloned CLPTM1L, which they called CRR9. The deduced 512-amino acid protein contains 5 putative transmembrane regions and shares 35% identity with CLPTM1.CRR9 was upregulated in all cisplatin-resistant cell lines examined. Overexpression of CRR9 in a cisplatin-sensitive cell line resulted in apoptosis, whereas CRR9 overexpression had no effect on a cisplatin-resistant cell line. CRR9 is not associated with cisplatin resistance but with cisplatin-induced apoptosis, and that cisplatin resistance is likely due to a signaling change downstream of CRR9.