Cancer stem cells similar to normal stem cells can thwart anti-cancer agentsJune 18, 2007Current cancer therapies often succeed at initially eliminating the bulk of the disease, including all rapidly proliferating cells, but are eventually thwarted because they cannot eliminate a small reservoir of multiple-drug-resistant tumor cells, called cancer stem cells, which ultimately become the source of disease recurrence and eventual metastasis. Now, research by scientists at the University of Pittsburgh School of Medicine suggests that for chemotherapy to be truly effective in treating lung cancers, for example, it must be able to target a small subset of cancer stem cells, which they have shown share the same protective mechanisms as normal lung stem cells. They are presenting this ground-breaking research at the Tissue Engineering and Regenerative Medicine International Society (TERMIS) North American Chapter meeting being held June 13 to 16 at the Westin Harbor Castle conference center in Toronto. The University of Pittsburgh researchers, led by Vera Donnenberg, Ph.D., assistant professor of surgery and pharmaceutical sciences, University of Pittsburgh Schools of Medicine and Pharmacy, used cell surface markers and dyes to identify cancer stem cells as well as normal adult stem cells and their progeny in samples obtained from normal lung and lung cancer tissue samples. The researchers identified a very small, rare set of resting cancer stem cells in the lung cancer samples that looked and behaved much like normal adult lung tissue stem cells. Both the cancer and normal stem cells were protected equally by multiple drug resistance transporters, even if the bulk of the tumor responded to chemotherapy. According to Dr. Donnenberg, the very fact that cancers can and do relapse after apparently successful therapy indicates the survival of a drug-resistant, tumor-initiating population of cells in many types of refractory cancers. "Because of the similarities between the way that normal stem cells and cancer stem cells protect themselves, cancer therapies have to be designed specifically to target cancer stem cells while sparing normal stem cells," she explained. University of Pittsburgh Schools of the Health Sciences |
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| Related Stem Cells Current Events and Stem Cells News Articles First use of antibody and stem cell transplantation to successfully treat advanced leukemia For the first time, researchers at Fred Hutchinson Cancer Research Center have reported the use of a radiolabeled antibody to deliver targeted doses of radiation, followed by a stem cell transplant, to successfully treat a group of leukemia and pre-leukemia patients for whom there previously had been no other curative treatment options. Magnetic nanoparticles to simultaneously diagnose, monitor and treat Whether it's magnetic nanoparticles (mNPs) giving an army of 'therapeutically armed' white blood cells direction to invade a deadly tumour's territory, or the use of mNPs to target specific nerve channels and induce nerve-led behaviour (such as the life-dependant thumping of our hearts), mNPs have come a long way in the past decade. Of mice and men: Stem cells and ethical uncertainties The recent creation of live mice from induced pluripotent stem cells (iPSCs) not only represents a remarkable scientific achievement, but also raises important issues, according to bioethicists at The Johns Hopkins University's Berman Institute of Bioethics. NIH-funded researchers transform embryonic stem cells into human germ cells Researchers funded in part by the National Institutes of Health have discovered how to transform human embryonic stem cells into germ cells, the embryonic cells that ultimately give rise to sperm and eggs. Stem cell therapy may offer hope for acute lung injury Researchers at the University of Illinois at Chicago College of Medicine have shown that adult stem cells from bone marrow can prevent acute lung injury in a mouse model of the disease. Placental precursor stem cells require testosterone-free environment to survive Trophoblast stem cells (TSCs), cells found in the layer of peripheral embryonic stem cells from which the placenta is formed, are thought to exhibit "immune privilege" that aids cell survivability and is potentially beneficial for cell and gene therapies. Endocrine Society calls for expanded scope and funding for stem cell research Stem cell research holds great promise for the treatment of millions of Americans with debilitating and possibly fatal diseases. Experimental treatments restore partial vision to blind people Two experimental treatments, a retinal prosthesis and fetal tissue transplant, restored some vision to people with blinding eye diseases. The findings, presented at Neuroscience 2009, the annual meeting of the Society for Neuroscience and the world's largest source of emerging news on brain science and health, may lead to new treatments for the blind. Scientists demonstrate link between genetic defect and brain changes in schizophrenia Researchers at the University of North Carolina at Chapel Hill School of Medicine have found that the 22q11 gene deletion - a mutation that confers the highest known genetic risk for schizophrenia - is associated with changes in the development of the brain that ultimately affect how its circuit elements are assembled. Small mechanical forces have big impact on embryonic stem cells Applying a small mechanical force to embryonic stem cells could be a new way of coaxing them into a specific direction of differentiation, researchers at the University of Illinois report. Applications for force-directed cell differentiation include therapeutic cloning and regenerative medicine. More Stem Cells Current Events and Stem Cells News Articles |
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