Agent for differentiating hematopoietic stem cell into natural killer cell comprising yc-1 or il-2 1 and a method of differentiating hematopoietic stem cell into natural killer cell using the same

The anticancer agent according to claim 6, wherein the cancer is selected from the group consisting of breast cancer, melanoma, stomach cancer, liver cancer, blood cancer, colon cancer and lung cancer.

An agent for natural killer (NK) cell differentiation comprising YC-1 [3-(5′-hydroxymethyl-2′-furyl)-1-benzylindazole] and IL-21 (Interleukin-21) as active ingredients.

An anticancer agent comprising YC-1 [3-(5′-hydroxymethyl-2′-furyl)-1-benzylindazole] and IL-21 (Interleukin-21) as active ingredients.

A method for differentiating hematopoietic stem cells into NK cells comprising the following steps:

• 1) inducing proliferation of NK precursor cells by adding a NK precursor inducer to hematopoietic stem cells;
• and
• 2) differentiating the NK precursor cells into mature NK cells by adding IL-21 and/or YC-1 to the NK precursor cells of step 1).

A method for increasing the killing activity of NK cells comprising the step of administering IL-21 (Interleukin-21) to hematopoietic stem cells which are undergoing differentiation into NK cells.

A method for increasing the killing activity of NK cells comprising the step of administering YC-1 [3-(5′-hydroxymethyl-2′-furyl)-1-benzylindazole] to hematopoietic stem cells which are undergoing differentiation into NK cells.

A method for increasing the killing activity of NK cells, comprising the step of administering YC-1 [3-(5′-hydroxymethyl-2′-furyl)-1-benzylindazole] and IL-21 (Interleukin-21) to hematopoietic stem cells which are undergoing differentiation into NK cells.

(canceled)

20-22. (canceled)