Modified iPS Cells Found Effective against Solid Cancers

Kyoto, May 13 (Jiji Press)–Immune cells derived from human induced pluripotent stem, or iPS, cells that are genetically modified to produce two specific proteins simultaneously can improve the therapeutic effect against solid cancers, a Japanese group said Wednesday. The findings may lead to a new treatment for solid tumors, which are difficult to combat with existing cancer immunotherapy using iPS cells. The group’s paper was published in the U.S. journal Molecular Therapy on the same day. Cancer immunotherapy, which activates immune cells in cancer patients to attack their tumors, has gained attention in recent years. However, while it shows effectiveness against blood cancers, its therapeutic outcomes for solid cancers have been limited as conventionally used cells have low ability to reach such cancers and proliferate nearby. For the research, the group, including members of Kyoto University’s Center for iPS Cell Research and Application, or CiRA, chose iPS cells, which can increase indefinitely and can be genetically modified easily. The group confirmed that immune cells made from iPS cells, when modified to produce the two proteins of IL-15 and IL-21 and administered to mice with hepatocellular carcinoma, suppressed cancer growth and improved survival rates compared with immune cells derived from conventional iPS cells. The study also found an increase in a substance that detects chemokine, a protein released by cancer cells, enhancing the ability of immune cells to migrate toward tumors. Additionally, it was shown that these modified cells maintain their strong ability to attack cancers and are also able to increase immune cells. “Using the two kinds of protein, we’ve managed to improve the migration and proliferation abilities of immune cells, which are necessary to treat solid cancers,” CiRA professor Shin Kaneko said. “Taking advantage of the characteristics of iPS cells, we can apply (the latest findings) to a new immunotherapy that can provide high-quality cells for treatment in large quantities and in a stable way.” END [Copyright The Jiji Press, Ltd.]