Stem cells could be used for personalized cancer treatment

Using cancer cells from an ovarian cancer patient and human embryonic stem cells, Israeli researchers have created a cancerous tumor in a mouse that mimics the way the tumor would develop in the patient's body.

The result is a pre-clinical experimental model for cancer research that could facilitate the development of personalized cancer therapies. The findings are published in the January 2009 online version of Clinical Cancer Research .

Until now, there have been very few pre-clinical experimental models in which cancer cells from an actual patient could be successfully grown in such a manner, say the researchers from the Technion-Israel Institute of Technology's Rappaport Faculty of Medicine and Rambam Medical Center.

The team, led by the Technion's Prof. Karl Skorecki and Dr. Maty Tzukerman, created the model by introducing a human patient's ovarian cancer stem cells into a teratoma (a growth made up of a mixture of human tissues, including blood vessels, fat tissue and connective tissue) in a mouse. The teratoma in the mouse was derived from human embryonic stem cells.

“Growing cancer stem cells from the patient in a way that mirrors their growth in the human body could allow clinicians to check the sensitivity of a particular tumor to different treatments,” explains Dr. Tzukerman. “This ability could provide clinicians with ways to customize cancer treatments for each individual patient.”

Skorecki and Tzukerman supervised Technion graduate student Ehood Katz, who from one patient isolated and characterized six different subpopulations of ovarian cancer cells, each of which was placed into a different teratoma. The cells from that one patient reflected the variety of characteristics of ovarian cancer in different patients, and also exposed the presence of “master cells” – the progenitors responsible for the recurrence and regrowth of cancer, even after derivative “daughter” cells are killed off by chemotherapy. These master cells in ovarian and other cancers appear to be the most important targets in anti-cancer treatments.

The research findings also emphasize that the choice of the environment in which to establish the experimental platform to grow cells and establish the tumor model is crucial. “The choice of the right milieu is critical in order to expose a subset of the most relevant cancer cells to study and target, and which otherwise might evade such study,” says Skorecki.

The Technion-Israel Institute of Technology is Israel's leading science and technology university. Home to the country's winners of the Nobel Prize in science, it commands a worldwide reputation for its pioneering work in nanotechnology, computer science, biotechnology, water-resource management, materials engineering, aerospace and medicine. The majority of the founders and managers of Israel's high-tech companies are alumni. Based in New York City, the American Technion Society (ATS) is the leading American organization supporting higher education in Israel, with 22 offices around the country.