Proteomic profiling of tumor-initiating cells in HT-29 human colorectal cancer cells

Recent reports have suggested that tumors are organized in heterogeneous populations. Within these populations, a small subpopulation of cells is more capable of initiating malignancy; these are called cancer stem cells. In this study, HT-29 cells were sorted according to the presence or absence of the cancer stem cell marker CD133. We confirmed that CD133+ cells possessed higher clonogenicity compared to CD133− cells. Furthermore, proteomic analysis identified 10 proteins, including actin-related protein 2/3 complex subunit 5-like and profilin 2. In conclusion, our data demonstrated that the expression of specific proteins associated with metastasis and invasion in CD133+ cells contributed to the stemness and tumorigenic properties of these cells.

► HT-29 colorectal cancer cell line was isolated into CD133+ or CD133− cells.
► We confirmed CD133+ cells are more tumorigenic and clonogenic than CD133− cells.
► Proteins were differentially expressed between CD133+ and CD133− HT-29 cells.
► ARP2/3 and profilin 2 related to actin polymerization are upregulated in CD133+ cells.
► The proteins contribute to stemness and tumorigenic properties of cancer stem cells.