Iowa-based research firms Cellular Engineering Technologies and John Paul II Medical Research Institute announced they were successful in designing a way to create stem cells that are safer to transplant without causing tumors. Previously, induced pluripotent stem cells (IPSCs), which are adult cells converted back into a stem cell form, required two cancer-causing genes in order to complete the conversion. Researchers were able to replace these genes with alternative methods of converting the cells, reducing the risk of transplanted cells growing into tumors. IPSCs had already been viewed as a breakthrough by avoiding the use of embryonically derived cells and instead transforming skin or blood cells into the multiuse stem cell form.