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A decade ago, gene expression seemed so straightforward: genes were either switched on or off. Not both. Then in 2006, a blockbuster finding reported that developmentally regulated genes in mouse embryonic stem cells can have marks associated with both active and repressed genes, and that such genes, which were referred to as "bivalently marked genes", can be committed to one way or another during development and differentiation. This paradoxical state—akin to figuring out how to navigate a red and green traffic signal—has since undergone scrutiny by labs worldwide. What has been postulated is that the control regions (or promoters) of...

While scientists hotly debate the existence of cancer stem cells, three related new studies, all conducted on mice, provide some supporting evidence. Stem cells are the foundation for healthy cell growth in the body. Some researchers believe that malignant stem cells also exist—so-called cancer stem cells that generate tumors and resist treatment by simply re-growing afterward. "Cancer stem cells are still controversial, but with progress in studies like these, it's less about whether they exist and more about 'what does this mean?'" said Dr. Max Wicha, director of the University of Michigan Comprehensive Cancer Center, who is familiar with the...

Enlarge Image Root killer. Cancer-like stem cells treated with the antipsychotic drug thioridazine (right) are scarce compared with control cells. Credit: E. Sachlos et al., Cell, 149 (8 June), ©2012 Elsevier Inc. A well-known drug for treating schizophrenia may be a cancer killer, too. In lab studies, the drug wiped out a precursor to leukemia cells without harming normal cells. That means it could give doctors a long-sought way to eliminate every trace of leukemia in patients so that the cancer can never come back. Even though surgery, chemotherapy, and radiation can get rid of a tumor or leukemia...

FINDINGS: Certain differentiated cells in breast tissue can spontaneously convert to a stem-cell-like state, according to Whitehead Institute researchers. Until now, scientific dogma has stated that differentiation is a one-way path; once cells specialize, they cannot return to the flexible stem-cell state on their own. These findings hold true for normal mammary cells as well as for breast cancer cells. RELEVANCE: These findings may redefine how researchers view cancer stem cells – the cells capable of seeding new tumors at primary and distant sites in the body. Therapies that specifically target cancer stem cells are currently being investigated in the...

Metformin Kills Breast Cancer Stem Cells, May Fight Many Cancers Reviewed by Louise Chang, MD The next breakthrough breast cancer treatment may be a diabetes drug already on the shelves of nearly every pharmacy. The drug is metformin, available generically and under brand names such as Glucophage and Fortamet. A growing body of evidence suggests that diabetes patients taking metformin are less likely to get cancer, and have better outcomes if they do get cancer, than those not taking the drug. Now Harvard researcher Kevin Struhl, PhD, and colleagues find that metformin can kill breast cancer stem cells, thought to...

Drug found that kills breast cancer stem cells.PunchstockA new approach for identifying drugs that specifically attack cancer stem cells, the cellular culprits that are thought to start and maintain tumour growth, could change the way that drug companies and scientists search for therapies in the war against cancer."We now have a systematic method that had not been previously known that allows us to find agents that target cancer stem cells," says Piyush Gupta of the Massachusetts Institute of Technology and the Broad Institute in Cambridge, Massachusetts, and first author of the study, published online today in Cell1.Applying the technique, Gupta...

Researchers have discovered a way to identify drugs that can specifically attack and kill cancer stem cells, a finding that could lead to a new generation of anticancer medicines and a new strategy of treatment. Many researchers believe that tumor growth is driven by cancerous stem cells that, for reasons not understood, are highly resistant to standard treatments. Chemotherapy agents may kill off 99 percent of cells in a tumor, but the stem cells that remain can make the cancer recur, the theory holds, or spread to other tissues to cause new cancers. Stem cells, unlike mature cells, can constantly...

A compound that appears to target the master cells which help breast cancers grow and spread has been discovered by US scientists.Some 16,000 chemicals were tested by researchers In tests in mice, salinomycin killed breast cancer stem cells far more effectively than some existing drugs, and slowed tumour growth. The drug, a farm antibiotic, has yet to be tested in humans, the journal Cell reports. But UK experts warned a human version could be some years away. This is one of the biggest advances we have seen this year in this area of research Dr John Stingl Cancer Research UK...

One of the current handicaps of cancer treatments is the difficulty of aiming these treatments at destroying malignant cells without killing healthy cells in the process. But a new study by McMaster University researchers has provided insight into how scientists might develop therapies and drugs that more carefully target cancer, while sparing normal healthy cells Mick Bhatia, scientific director of the McMaster Stem Cell and Cancer Research Institute in the Michael G. DeGroote School of Medicine, and his team of investigators have demonstrated – for the first time – the difference between normal stem cells and cancer stem cells in...

OKLAHOMA CITY — Doctors at the OU Cancer Institute announced Friday that they have discovered a way to find cancer stem cells in tumors, destroy them and keep them from reoccurring. The team of researchers, led by Dr. Courtney Houchen, M.D. and Shrikant Anant, Ph.D., are using the Mushashi-1 protein, which only appears in adult stem cells, to develop a compound that can kill the stem cells and cancer cells, while leaving normal cells untouched. This is the first time doctors have been able to separate the cancer forming stem cells from normal cells. Houchen said they are going after...

Stem cells -- popularly known as a source of biological rejuvenation -- may play harmful roles in the body, specifically in the growth and spread of cancer. Amongst the wildly dividing cells of a tumor, scientists have located cancer stem cells. Physician-scientists from Weill Cornell Medical College are studying these cells with hopes of combating malignant cancers in the brain. "Some patients' brain tumors respond to chemotherapy and some don't," says Dr. John A. Boockvar, the Alvina and Willis Murphy Assistant Professor of Neurological Surgery and head of the Brain Tumor Research Group at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. "We...

Starving the source. Cancer stem cells (dark purple) reside near capillaries and give rise to normal tumor cells (light purple). They die when drugs target the capillary blood supply (bottom).Credit: Cancer Cell Sacking Cancer Stem Cells By Meagan WhiteScienceNOW Daily News16 January 2007 Scientists have found the Achilles' heel of cells that jump start tumor growth. According to a new study, these "cancer stem cells" reside in blood vessels. Disrupting these vessels, say the researchers, may prove a far more effective cancer therapy than targeting other regions of a tumor. Cancer biologists once believed that all cells in a tumor...

One day, perhaps in the distant future, stem cells may help repair diseased tissues. But there is a far more pressing reason to study them: stem cells are the source of at least some, and perhaps all, cancers. At the heart of every tumor, some researchers believe, lie a handful of aberrant stem cells that maintain the malignant tissue.  The idea, if right, could explain why tumors often regenerate even after being almost destroyed by anticancer drugs. It also points to a different strategy for developing anticancer drugs, suggesting they should be selected for lethality to cancer stem cells and...

Imagine a cell nestled happily in the human body and enjoying the best of all possible worlds. It is endowed with immortality, the remarkable ability to divide indefinitely. Each time it cleaves, it makes two daughter cells with different fates. One divides again and again and again, spawning hundreds of copies of itself before exhausting its powers of duplication and dying out. The other progeny is a bit more cunning, inheriting from its parent the gift of never-ending life. That cell resists the temptation to multiply and march to an inevitable death, choosing instead to divide only occasionally and, by...