title: Ectopic expression of reg protein: A marker of colorectal mucosa at risk for neoplasia.
abstract: Pancreatic regenerating gene (reg I) messenger RNA is overexpressed within the pancreas following injury and resection. Its level of expression corresponds to the level of cellular dedifferentiation. Human reg I has been localized to chromosome 2p12, and ectopic expression of its mRNA has been found within colorectal tumors. We postulated that colorectal production of reg I might either be a marker for the presence of cancer or define mucosa at risk for development of neoplasia. Using a monoclonal antibody to reg I, regenerating gene protein was histochemically mapped in 56 cases of documented colorectal adenocarcinoma. In sections of colon from normal control subjects no reg I protein was noted, whereas 58.9% of the specimens from cancer patients stained positive for reg I. Although a correlation was noted between reg I staining and Dukes' stage, there was no correlation with histologic grade or 5-year patient survival. In 39 of 55 cancer specimens the transition zone (interface) between the neoplasm and normal mucosa was visualized; 100% of the transition zones contained cells that stained strongly positive for reg I. We conclude that reg I protein is ectopically expressed in colorectal mucosa at the transition zone of colorectal cancer, and occasionally within the tumor itself. Although ectopic reg I expression in colorectal epithelia is not a marker for the presence of carcinoma, it may be a sensitive marker for mucosa at risk for development of neoplasia.
authors.affiliation: Department of Surgery, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, NY 10461, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Zenilman
authors.forename: S
authors.initials: S
authors.lastname: Kim
authors.forename: B A
authors.initials: BA
authors.lastname: Levine
authors.forename: C
authors.initials: C
authors.lastname: Lee
authors.forename: J J
authors.initials: JJ
authors.lastname: Steinberg
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000368:Aged; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D051847:Lithostathine / Q000096:biosynthesis*; D008297:Male; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor; D051847:Lithostathine; C497617:REG1A protein, human