Brief Article
Copyright ©2010 Baishideng. All rights reserved
World J Gastroenterol. Feb 14, 2010; 16(6): 732-739
Published online Feb 14, 2010. doi: 10.3748/wjg.v16.i6.732
ABCG5-positivity in tumor buds is an indicator of poor prognosis in node-negative colorectal cancer patients
lsabel Hostettler, Inti Zlobec, Luigi Terracciano, Alessandro Lugli
lsabel Hostettler, Inti Zlobec, Luigi Terracciano, Alessandro Lugli, Institute for Pathology, University Hospital of Basel, Schoenbeinstrasse 40, Basel, CH-4031, Switzerland
Author contributions: Hostettler I and Zlobec I contributed equally to the research; Hostettler I collected and interpreted the data; Lugli A designed the study, conceptualized the project and interpreted the data; Zlobec I analyzed and interpreted the data and drafted the manuscript; Terracciano L provided the material and administrative support; All authors played a role in the editing, revision and final approval of this manuscript.
Supported by The Krebsliga Beider Basel (Zlobec I, Terracciano L and Lugli A)
Correspondence to: Dr. Alessandro Lugli, MD, Institute for Pathology, University Hospital of Basel, Schoenbeinstrasse 40, Basel, CH-4031, Switzerland.
Telephone: +41-61-2652390 Fax: +41-61-2653194
Received: September 18, 2009
Revised: November 2, 2009
Accepted: November 9, 2009
Published online: February 14, 2010

AIM: To analyze the expression of 8 putative cancer stem cell (CSC) markers within colorectal cancer tumor buds and to determine their prognostic impact in patients with this disease.

METHODS: Immunohistochemistry was performed on 101 colorectal cancer resections for CK22 (to identify tumor buds) as well as CD133, CD166, CD24, CD44s, CD90, EpCAM, ALDH1, and ABCG5, and their expression within tumor buds was evaluated.

RESULTS: CD90, CD44s, and CD133 expression in tumor buds was found in less than 5% of all cases. ALDH1, CD24, CD166 were expressed in 16.5%, 16.2%, and 34% cases, respectively, while ABCG5 and EpCAM expression was more frequent and found in 35% and 69% of cases, respectively. Of the 8 markers studied, EpCAM and ABCG5 positivity in tumor buds were significantly associated with poor prognosis (P = 0.023, P = 0.038, respectively) in multivariable analysis with pT and pN classification [P = 0.048; hazard ratio (HR): 2.64; 95% CI: 1.0-6.9, for EpCAM and P = 0.029; HR: 2.22; 95% CI: 1.0-4.5, for ABCG5]. Poor survival time was particularly striking for lymph node-negative patients with ABCG5-positive buds (P < 0.001).

CONCLUSION: Expression of putative stem cell markers EpCAM and ABCG5 within the tumor buds of colorectal cancer are frequently noted and are associated with poor prognosis.

Keywords: Colorectal cancer, Cancer stem cells, Tumor budding, ABCG5, Prognosis