Isolation and characterization of cancer stem-like cells from MHCC97H Cell Lines

Objective

To identify and isolate CD133 positive cancer stem-like cells (CD133⁺ cells) from the highly invasive human hepatocellular carcinoma cell line(MHCC97H), and examine their potential for clonogenicity and tumorigenicity.

Methods

CD133⁺ and CD133⁻ cells were isolated from MHCC97H cell line by magnetic bead cell sorting(MACS), and the potentials of CD133⁺ cells for colony formation and tumorigenicity were evaluated by soft agar cloning and tumor formation following nude mice inoculation.

Results

CD133⁺ cells represent a minority(0.5-2.0%) of the tumor cell population with a greater colony-forming efficiency and greater tumor production ability. The colony-forming efficiency of CD133⁺ cells in soft agar was significantly higher than CD133⁻ cells(36.8 ± 1.4 vs 12.9 ± 0.8, P < 0.05). After 6 weeks, 3/5 mice inoculated with 1 × 10³ CD133⁺ cells, 4/5 with 1 × 10⁴ CD133⁺ cells and 5/5 with 1 × 10⁵ CD133⁺ cells developed detectable tumors at the injection site, while only one tumor was found in mice treated with same numbers of CD133⁻ cells.

Conclusion

CD133 may be a hallmark of liver cancer stem cells (CSC) in human hepatocellular carcinoma(HCC), because the CD133⁺ cells identified and isolated with anti-CD133 labeled magnetic beads from MHCC97H cell line exhibit high potentials for clonogenicity and tumorigenicity. These CD133⁺ cells might contribute to hepatocarcinogenesis, as well as the growth and recurrence of human HCC, and therefore may be a useful target for anti-cancer therapy.