title: Dipeptidase 1: a candidate tumor-specific molecular marker in colorectal carcinoma.
abstract: The aim of this study was to identify tumor-specific markers for the detection of rare disseminated colorectal tumor cells in peripheral venous blood and in intra-peritoneal saline lavage samples collected before and after resection of colorectal tumors. Using cDNA micro-array screening, we found dipeptidase 1 (DPEP1) to be highly expressed in colon tumors compared to matched normal mucosa. Relative reverse transcriptase (RT)-PCR showed that DPEP1 was over-expressed by >/=2 fold in colon tumor compared to normal colonic mucosal tissue in 56/68 (82%) patients. Using immunobead RT-PCR, a technique that first enriches for epithelial cells, we found DPEP1 positive cells in intra-peritoneal lavage and venous blood samples from 15/38 (39%) colorectal cancer cases. This is the first report of DPEP1 as a marker for disseminated colon tumor cells.
authors.affiliation: Department of Haematology-Oncology, The Basil Hetzel Institute, The Queen Elizabeth Hospital, 28 Woodville Rd, Woodville, SA, 5011, Australia.
authors.forename: C M
authors.initials: CM
authors.lastname: McIver
authors.forename: J M
authors.initials: JM
authors.lastname: Lloyd
authors.forename: P J
authors.initials: PJ
authors.lastname: Hewett
authors.forename: J E
authors.initials: JE
authors.lastname: Hardingham
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000201:enzymology*; D018076:DNA, Complementary / Q000378:metabolism; D004150:Dipeptidases / Q000378:metabolism / Q000502:physiology*; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D058851:GPI-Linked Proteins; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D014408:Biomarkers, Tumor; D018076:DNA, Complementary; D058851:GPI-Linked Proteins; D004150:Dipeptidases; C038937:dipeptidase; C549872:dipeptidase 1