CLIC4, ERp29, and Smac/DIABLO derived from metastatic cancer stem-like cells stratify prognostic risks of colorectal cancer.

Purpose: Cancer stem-like cells have been well accepted to be involved in recurrence and metastasis of cancers, but the prognostic potential of biomarkers integrating with metastasis and cancer stem-like cells for colorectal cancer is unclear.

Experimental Design: We identified three proteins, CLIC4, ERp29, and Smac/DIABLO, from metastatic cancer stem-like cells of colorectal cancer and verified the proteins' role in metastatic behaviors. The proteins were detected by IHC in colorectal cancer tumors and matched colonic mucosa from patients with colorectal cancer who underwent radical surgery in the training cohort. The associations between proteins expression levels and five-year disease-specific survival (DSS) were evaluated to predict the survival probability in the training cohort of 421 cases and the validation cohort of 228 cases.

Results: A three-protein panel including CLIC4, ERp29, and Smac/DIABLO, which was generated from multivariate analysis by excluding clinicopathologic characteristics from the training cohort, distinguished patients with colorectal cancer into very low-, low-, middle-, and high-risk groups with significant differences in five-year DSS probability (88.6%, 63.3%, 30.4%, 11.4%; P < 0.001). The panel is independent from tumor-node-metastasis staging system and histologic grading to predict prognosis, and also enables classification of validation cohort into four risk stratifications (five-year DSS probability is 98.2%, 80.2%, 25.6%, and 2.7%; P < 0.001).

Conclusions: CLIC4, ERp29, and Smac/DIABLO integrated into a novel panel based on cancer stem-like cells in association with metastasis stratify the prognostic risks of colorectal cancer. Prediction of risks with molecular markers will benefit clinicians to make decisions of individual management with postoperative colorectal cancer patients.