PCD1, a novel gene containing PDZ and LIM domains, is overexpressed in several human cancers

In an effort to discover novel genes differentially expressed in human panc reatic cancer, we have identified a gene named PCD1 (pancreatic cancer deri ved) that is up-regulated in pancreatic dysplasia and cancer relative to no rmal pancreatic ductal epithelium, We cloned the full length (4572 bp) of t his gene, which encodes a novel protein of 1064 amino acids containing a PD Z domain and a LIM domain. An alternatively spliced form with a deletion of 30 bp in the coding region was also found, In situ hybridization results s howed that PCD1 is highly expressed in a significant percentage of colon, b reast, liver, lung, pancreas, stomach, and prostate tumor tissues but is ex pressed in very few normal tissues, Northern blot hybridization confirmed t he overexpression of PCD1 in colon and breast tumor tissues and also showed strong expression of PCD1 in the heart as well as in HeLa cells. Real-time quantitative reverse transcription-PCR verified the overexpression of PCD1 in primary colon tumors or in liver metastases relative to normal colon ti ssues in five of eight patients. The PCD1 gene maps to human chromosome 13q 21.33. Because of its high levels of expression in neoplastic tissues and t he presence of both PDZ and LIM domains, we suggest that PCD1 may play an i mportant role in cytoskeletal reorganization during carcinogenesis.