CD44 and neoplasm: To analyze the subpopulation of CD133+CD44+ cells with metastatic capacity in more detail, microarray analysis of the CD133+CD44+ and CD133−CD44− tumor cells was performed; the cells were clustered into two separate subgroups, and the results showed that the expression of Wnt-, EMT-, and TM-related genes was significantly changed in the CD133+CD44+ subset (Figure 6).