Consistent with this hypothesis, CD133 expression has been reported to be highly expressed in colon cancers with early liver metastases and to be a potential biomarker for the early liver metastases[41] and we also previously reported an increased percentage of CD133+ cells, assessed by flow cytometry, in metastatic vs primary colon cancers,[42]. The gene discussed is PROM1; the disease is malignant colon neoplasm.