Treatment methods for controlling the growth of cancer might transform cancer from a terminal disease to a chronic, manageable one, Israeli researchers said. Co-senior authors Karl Skorecki of the Rambam Health Care Campus and Maty Tzukerman, a Rambam senior research scientist with the Technion-Israel Institute of Technology, placed cancer cells in and near a growth developed from human stem cells, to develop a teratoma -- a tumor made of a heterogenous mix of cells and tissues -- by enabling the differentiation of human embryonic stem cells into a variety of normally occurring human cell lines on a special mouse. The research team took cells from one woman\'s ovarian clear cell carcinoma and injected them either into or alongside the human stem cell-derived environment. \"We noticed very early on, rather strikingly, that the human cancer cells grow more robustly when they are in the teratoma environment compared to any other means in which we grew them, such as in a mouse muscle or under the skin of a mouse,\" Skorecki said in a statement. The researchers said they do not yet know the cues that enhance the cancer\'s proliferation but the team is working on isolating the factors from human cells that promote such self-renewing properties, which may eventually allow physicians to manage cancer as a chronic disease. Instead of one therapy against the entire tumor, researchers may develop a method to tease out the variety of self-renewing cell lines of a particular tumor and determine what allows each to thrive, and then attack that mechanism, Skorecki said. The findings were published in online issue of the journal Stem Cells.