Research papersAntiproliferative effect of 1,4-phenylenebis(methylene)selenocyanate (p-XSC) on colonic epithelium of patients with adenomatous polyps in vitroBartram, H-P; Krüger, S; Dusel, G; El-Bayoumy, K; Upadhyaya, P; Scheppach, WAuthor Information 1Gastroenterological Practice, Bahnhofstr. 29, 86150 Augsburg, Germany 2Department of Medicine, University of Wurzburg, Germany 3American Health Foundation, Valhalla, New York, USA 4University of Minnesota Cancer Center, Minneapolis, MN, USA Correspondence to: H-P Bartram. Fax: (+49) 821 158 425 E-mail: HP.Bartram@t-online.de Received 22 April 2003 Accepted 29 September 2003 European Journal of Cancer Prevention: December 2003 - Volume 12 - Issue 6 - p 463-468 Buy Abstract We have consistently shown that the organoselenium compound 1,4–phenylenebis(methylene)selenocyanate (p-XSC) is a superior cancer chemopreventive agent and less toxic than selenite or certain naturally-occurring selenoamino acids. To elucidate the effects of p-XSC on human colonic mucosa, biopsies from endoscopically normal sigmoid colon of 30 patients with adenomatous polyps were incubated with p-XSC at concentrations of 1, 2 and 5 μmol/l dissolved in dimethylsulphoxide (DMSO). Biopsies incubated with DMSO or pure culture medium served as a control. Proliferating cells were labelled by bromodeoxyuridine immunohistochemistry and the labelling index (LI) was computed. Upper crypt labelling index (LI of crypt compartments 4+5) and Φh value, which are both discriminators of the expansion of the proliferative zone, were significantly lower after incubation with 1 and 5 μmol/l p-XSC, respectively (LI 4+5: 0.8 and 1.0; Φh value: 2.1 and 2.4), as compared with DMSO (LI 4+5: 3.6 and 4.5; Φh value: 7.0 and 8.3) or culture medium (LI 4+5: 3.3 and 4.5; Φh value: 7.2 and 8.1) (P<0.005 and P<0.05 by Friedman's block test). A trend towards lower levels of LI 4+5 (P=0.059) and Φh value (P=0.075) were seen after 2 μmol/l p-XSC incubation compared with DMSO. Since hyperproliferation of colonic crypt cells with expansion of the proliferative zone is regarded as a biomarker of increased cancer risk, the antiproliferative effects of p-XSC especially on upper crypt LI and Φh value may indicate a possible protective effect of this organoselenium compound in the prevention of human colon cancer development. Copyright © 2003 Wolters Kluwer Health, Inc. All rights reserved.