PROM1 and neoplasm: Currently, authors advocate that the recurrence and chemoresistance are the main problems for its treatment.1 Cancer stem cells (CSCs), also called tumor-initiating cells, have received high attention because they play a pivotal role in tumor invasion, metastasis and resistance to conventional therapy.2 Several molecular biomarkers have been used in clinical trials to demonstrate the existence of CSCs, among which CD133 is a valid marker for identifying cancer stem cells from fresh surgically resected colorectal cancer tissues to predict the early recurrence in colorectal cancer.3,4