Researchers in Japan say they have started a clinical trial of ovarian cancer treatment involving immune cells created from induced pluripotent stem cells, or iPS cells.

The team of researchers from the National Cancer Center Hospital East and Kyoto University’s Center for iPS Cell Research and Application made the announcement in an online news conference on Thursday.

The iPS cells used in the treatment are capable of developing into any kind of cell. A gene that reacts strongly to a protein unique to a certain type of ovarian cancer is inserted into iPS cells to create natural killer cells. These NK cells will then be injected into the ovaries of patients with this type of ovarian cancer.