Dr. Jiyong Lee and his students

Dr. Jiyong Lee (right) and his team of researchers are working to identify biological targets that might be susceptible to novel tumor-suppressing drugs for breast cancer.

The Cancer Prevention and Research Institute of Texas (CPRIT) recently awarded a grant to Dr. Jiyong Lee, assistant professor of chemistry at The University of Texas at Dallas, for research that may lead to more effective treatments for breast cancer and methods to prevent its recurrence in patients.

Lee’s CPRIT grant of $194,500 will support research aimed at identifying biological targets on breast cancer stem cells that might be susceptible to novel tumor-suppressing drugs.

To understand the significance of Lee’s research, here is some background on stem cells. In general, stem cells are unspecialized cells in the human body, capable of dividing and renewing themselves on an unlimited basis. Embryonic stem cells, which are derived from very early embryos, are capable of generating all types of cells in the body during normal development. Adult stem cells, on the other hand, originate in specific tissues in the body, and can produce cells only of that particular tissue type, such as blood, nerve and muscle cells.

Cancer stem cells (CSCs) combine the self-renewing power of stem cells with the uncontrolled proliferation of cancer cells. CSCs were first identified in leukemia in the late 1990s. While the question of how they originate in different tissues is still under investigation, CSCs have since been detected in other types of cancer, including breast cancer tumors.

“Breast cancer stem cells display stem-cell characteristics such as self-renewal, and the ability to differentiate into any type of cells that could be found in a tumor,” Lee said. “They differ from normal stem cells in that cancer stem cells have dysregulated self-renewal, leading to unlimited and uncontrolled cell growth.”

Lee said that while some chemotherapies or anti-cancer treatment approaches have been successful in suppressing tumor cell growth, these strategies are not very effective in eliminating the cancer stem cells.

“Aggressive types of breast cancer that are highly invasive and metastatic usually relapse a few years after removal of the primary tumors because the cancer stem cells have survived,” Lee said. “That’s why metastatic breast cancer, which can spread to other tissues in the body, remains a big challenge for clinicians.

“Identifying and developing novel therapeutics targeting breast cancer stem cells is a great strategy to kill breast cancer from its root. Together with conventional anti-tumor therapies, these could not only suppress growth of the existing tumors, but also prevent recurrence and the development of metastatic tumors.”

Lee’s grant falls under CPRIT’s High Impact/High Risk program. He said CSCs are an exciting topic for researchers, but there are hurdles.

For example, creating models of how CSCs continuously renew themselves is difficult. In addition, because they occupy only a very small percentage of the whole cancer cell population in a tumor, they are challenging to study in the lab.

Despite the obstacles, Lee said the pursuit is well worth the effort, given the potential payoff.

“It is highly worthwhile to try to discover new strategies that specifically target such a small portion of cells,” Lee said. “This is the root of the tumor, so tearing out cancer stem cells should be an effective way to dispel the chance of cancer relapse.”