Nuclear expression of CXCR4 is associated with advanced colorectal cancer.
OBJECTIVE
CXCR4 and its ligand, SDF-1alpha, play an important role in the targeted metastasis of colon cancer. In this study, we analyzed an expression of CXCR4 in clinical samples and showed that SDF-1alpha affected the expression of CXCR4 in colon cancer cells.


METHODS
A total of 388 patients with colorectal cancer (CRC) who underwent surgery in Taipei Veterans General Hospital from 2000 to 2004 were included. The expression of CXCR4 in CRC was visualized by immunohistochemistry (anti-CXCR4 mAb, R&D 12G5). HCT116, SW480, and SW620 cells were treated with SDF-1alpha in vitro and the CXCR4 proteins located in the cytoplasmic and nuclear compartments were separated and analyzed with western blotting.


RESULTS
The frequency of cytoplasmic and nuclear expression of CXCR4 in colorectal cancers was 35.6% and 36.9%, respectively. Nuclear but not cytoplasmic expression of CXCR4 was associated with advanced CRC (p < 0.001) and lymphovascular invasion. However, in multivariate analysis, nuclear expression of CXCR4 did not correlate with patients' outcome. In the in vitro study, SDF-1alpha, stimulation of three colorectal carcinoma lines enhanced the CXCR4 nuclear expression.


CONCLUSIONS
Expression of the CXCR4 plays a role in CRC progression and may be associated with SDF-1alpha stimulation.
Wang
Shang-Chiung
SC
Division of Colon and Rectal Surgery, Department of Surgery, Taipei Veterans General Hospital, National Yang-Ming University, Taipei, Taiwan.
Lin
Jen-Kou
JK
Wang
Huann-Sheng
HS
Yang
Shung-Haur
SH
Li
Anna Fen-Yau
AF
Chang
Shih-Ching
SC
D000368:Aged; D002467:Cell Nucleus / Q000737:chemistry / Q000473:pathology*; D054377:Chemokine CXCL12 / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000473:pathology*; D003593:Cytoplasm / Q000737:chemistry; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D019718:Receptors, CXCR4 / Q000032:analysis*; D016896:Treatment Outcome
D054377:Chemokine CXCL12; D019718:Receptors, CXCR4