GastrointestinalCirculating CD133+/ESA+ cells in colorectal cancer patients

BackgroundTumor initiating cells are a small subset of cancer cells responsible for tumor growth and recurrence. The status of tumor initiating cells was measured using the surface markers CD133 (prominin-1) and ESA (epithelial-specific antigen). The aims of this study were to investigate the significance of CD133+/ESA+ cells in mesenteric venous blood (MVB) and tumor mass (TM) for overall survival (OS) and disease-free survival (DFS) in colorectal cancer (CRC) patients undergoing curative resection.Materials and methodsA total of 229 CRC patients undergoing curative resection were prospectively enrolled in the study. Using CD133 and ESA as surface markers, CD133+/ESA+ cells were enumerated from MVB and TM using flow cytometry.ResultsWe analyzed the presence of CD133+/ESA+ cells in TM from 158 patients and found no correlation to patient DFS, OS, or clinical stage. In 135 patients, an analysis of CD133+/ESA+ cells in MVB showed an inverse correlation with both DFS and OS (P = 0.014 and P = 0.008, respectively). It exhibited an increase-then-decrease pattern with the peak in stage II patients. A multivariate Cox analysis demonstrated that the status of CD133+/ESA+ cells in MVB, but not the TM, was a significant prognostic factor for DFS and OS (P = 0.003 and P = 0.011, respectively).ConclusionsThe status of CD133+/ESA+ cells in MVB, but not in TM, could be a useful indicator for predicting tumor recurrence and a prognostic marker for CRC patients.