Elevated RBP-Jκ and CXCL11 Expression in Colon Cancer is Associated with an Unfavorable Clinical Outcome.

Introduction: This study aims at exploring the expression and significance of recombination signal-binding protein for immunoglobulin kappa J region (RBP-Jκ) and C-X-C motif chemokine 11 (CXCL11) in human colon cancer tissues.

Methods: The RBP-Jκ and CXCL11 expression levels were assessed by immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR) in patients with colon cancer, and their prognostic significance was evaluated.

Results: Through analyzing 342 samples of colon cancer patients treated at our institution, increased expression of RBP-Jκ and CXCL11 was found in human colon cancer specimens compared with matched paratumorous normal specimens (<0.001). A positive correlation was found between RBP-Jκ expression and CXCL11 expression (<0.001). High RBP-Jκ expression was significantly associated with poorly differentiated tumors (=0.005), invasion beyond propria muscularis (=0.025), lymph node metastases (=0.005), distant metastasis (<0.001), advanced tumor-node-metastasis (TNM) stage (=0.004), and a shorter overall survival (<0.001). An increase in CXCL11 protein expression was associated with poorly differentiated tumors (=0.015), invasion beyond propria muscularis (=0.029), lymph node metastases (=0.031), distant metastasis (=0.045), advanced TNM stage (=0.026), and a shorter overall survival of patients (<0.001). In multivariate Cox regression analysis, RBP-Jκ protein expression (=0.036), CXCL11 protein expression (=0.001), differentiation (<0.001), depth of invasion (=0.009), distant metastasis (<0.001), and TNM stage (<0.001) were independent prognostic indicators of colon cancer.

Conclusion: High expression of RBP-Jκ is closely associated with high CXCL11 expression, which represents a risk factor for the poor overall survival of colon cancer patients.