Chemokine receptor CXCR4 expression in colorectal cancer patients increases the risk for recurrence and for poor survival.
OBJECTIVE
Liver metastasis is the predominant cause of colorectal cancer (CRC) related mortality. Chemokines, soluble factors that orchestrate hematopoetic cell movement, have been implicated in directing cancer metastasis, although their clinical relevance in CRC has not been defined. Our hypothesis was that the chemokine receptor CXCR4 expressed by CRC is a prognostic factor for poor disease outcome.


METHODS
CRC cell lines (n = 6) and tumor specimens (n = 139) from patients with different American Joint Committee on Cancer (AJCC) stages of CRC were assessed. Microarray screening of select specimens and cell lines identified CXCR4 as a prominent chemokine receptor. CXCR4 expression in tumor and benign specimens was assessed by quantitative real-time reverse transcription polymerase chain reaction and correlated with disease recurrence and overall survival.


RESULTS
High CXCR4 expression in tumor specimens (n = 57) from AJCC stage I/II patients was associated with increased risk for local recurrence and/or distant metastasis (risk ratio, 1.35; 95% CI, 1.09 to 1.68; P = .0065). High CXCR4 expression in primary tumor specimens (n = 35) from AJCC stage IV patients correlated with worse overall median survival (9 months v 23 months; RR, 2.53; 95% CI, 1.19 to 5.40; P = .016). CXCR4 expression was significantly higher in liver metastases (n = 39) compared with primary CRC tumors (n = 100; P < .0001).


CONCLUSIONS
CXCR4, a well-characterized chemokine receptor for T-cells, is differentially expressed in CRC. CXCR4 gene expression in primary CRC demonstrated significant associations with recurrence, survival, and liver metastasis. The CXCR4-CXCL12 signaling mechanism may be clinically relevant for patients with CRC and represents a potential novel target for disease-directed therapy.
Kim
Joseph
J
Department of Molecular Oncology, John Wayne Cancer Institute, 2200 Santa Monica Blvd., Santa Monica, CA 90404, USA.
Takeuchi
Hiroya
H
Lam
Stella T
ST
Turner
Roderick R
RR
Wang
He-Jing
HJ
Kuo
Christine
C
Foshag
Leland
L
Bilchik
Anton J
AJ
Hoon
Dave S B
DS
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology*; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics* / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000503:physiopathology; D009364:Neoplasm Recurrence, Local / Q000235:genetics*; D011379:Prognosis; D019718:Receptors, CXCR4 / Q000096:biosynthesis*; D012307:Risk Factors; D015398:Signal Transduction; D016019:Survival Analysis; D014407:Tumor Cells, Cultured
D019718:Receptors, CXCR4