ANTI-TUMOR EFFECT OF ANTI-CD133 CHIMERIC ANTIGEN RECEPTOR T CELLS AGAINST CHOLANGIOCARCINOMA CELLS
Cholangiocarcinoma is the second most common liver cancer with no effective curative treatment. Chimeric antigen receptor (CAR) T cell is genetically modified T cells enables direct-targeting tumor-associated antigen without requirement of major histocompatibility complex. Remarkable clinical outcomes of CAR T cells have been shown in hematological malignancies; however, the anti-tumor effect against cholangiocarcinoma is still unclear. Overexpression of CD133 tumor-associated antigen was found in cholangiocarcinoma patients related to low survival rate and high metastasis. In addition, CD133 has been considered as a cancer stem cell marker, which plays role in tumor progression and resistance to therapy. Thus, it is interesting to investigate whether cholangiocarcinoma cells can be eradicated by CAR T cells targeting to CD133 (CD133-CART).
Initially, expression of CD133 on KKU-213 cell line was examined by using flow cytometry. Lentiviral vector containing CD133-CAR was constructed and its expression in human cell line (HEK293T) was tested by using immunoblotting of CD3z. Then, CD133-CART cells were generated using lentiviral transduction. Finally, anti-tumor effect of CD133-CART were examined under fluorescent microscope.
Here, we report that CD133-CART exhibits anti-tumor effect against cholangiocarcinoma patient-derived KKU-213 cell line. The membranous CD133 expression represents possible target for CAR T cells treatment. Co-culture of CD133-CART and fluorescent protein-expressing KKU-213 cell lines resulted in tumor cell lysis at different effector to target ratio.
Thus, this study indicates feasibility and potent anti-tumor effect of CD133-CART against cholangiocarcinoma KKU-213 cells, which will be further developed for treatment of cholangiocarcinoma and other CD133-expressing tumors.