Cytoplasmic CD24 expression in colorectal cancer independently correlates with shortened patient survival.
OBJECTIVE
CD24 is a cell adhesion molecule that has been implicated in metastatic tumor progression of various solid tumors. We aimed to clarify the expression patterns of CD24 in colorectal cancer and to correlate these to clinicopathologic variables including patient survival.


METHODS
147 colorectal carcinomas and two colon carcinoma cell lines were immunostained for CD24. Cytoplasmic and membranous immunoreactivity were semiquantitatively scored. Fisher's exact test, chi(2) test for trends, Kaplan-Meier analysis, and Cox's regression were applied.


RESULTS
The cell line CX-2 showed only a minimal membranous CD24 immunoreactivity, in contrast to HT29, which stained strongly in the cytoplasm. In colorectal cancer, 68.7% of the tumors showed membranous CD24 staining, whereas 84.4% showed cytoplasmic staining. In 10% of cases, an exceptionally strong cytoplasmic CD24 expression was observed. The latter significantly correlated to higher tumor stages (Dukes and pT), nodal or systemic metastasis, and higher tumor grade. In survival analysis, strong cytoplasmic CD24 expression correlated significantly (Cox's regression: P = 0.012, relative risk = 3.7) to shortened patient survival in the group of cases without distant metastases.


CONCLUSIONS
CD24 is commonly up-regulated in colorectal cancer and is a new independent prognostic marker which corroborates the importance of CD24 in tumor progression of this disease.
Weichert
Wilko
W
Institute of Pathology and Tumor Center, Charité University Hospital, Berlin, Germany.
Denkert
Carsten
C
Burkhardt
Mick
M
Gansukh
Tserenchunt
T
Bellach
Joachim
J
Altevogt
Peter
P
Dietel
Manfred
M
Kristiansen
Glen
G
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000096:biosynthesis*; D051927:CD24 Antigen; D045744:Cell Line, Tumor; D016009:Chi-Square Distribution; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology*; D003593:Cytoplasm / Q000737:chemistry; D005455:Fluorescent Antibody Technique; D019073:HT29 Cells; D006801:Humans; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D018613:Microscopy, Confocal; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016019:Survival Analysis; D013997:Time Factors
D015703:Antigens, CD; D051927:CD24 Antigen; C497889:CD24 protein, human; D008562:Membrane Glycoproteins