A new study provides hypothesis why obese patients are less successful during the treatment of cancer -
Through many types of cancer, obese patients are less successful than most patients lean. Now, a study by the University of Colorado Cancer Center published in the journal Cell Stem offers a compelling case why: the researchers found that the stem cells of leukemia "hide" in the fatty tissue, even transform this fabric so support their survival when challenged with chemotherapy. It is as if the leukemia stem cells use not only fatty tissue that den of thieves hiding therapy, but actively adapt this cave to their liking.
"It has been increasingly appreciated that cancer can originate from stem cells that do not kill the cancer stem cells can lead to a relapse the researchers also learned to appreciate the importance of tissue surrounding. - the "niche" or tumor microenvironment. - supporting the cancer stem cells in leukemia, the obvious niche is the bone marrow, but little attention was paid to other sites in the body. this study is one of the first to evaluate adipose tissue, fat, as a niche tumor support possible, "said Craig Jordan, Ph.D., a researcher at the CU Cancer Center and Carroll Nancy Allen Professor of hematology department CU of Medicine.
Jordan describes how the line "very original and insightful" the lead author of reasoning Haobin Ye, Ph.D., was essential for the study. First, patients with obese leukemia have worse outcomes. Second, the stem cells stimulate growth, resist the therapy and can create a relapse in leukemia. Third, the tumor microenvironment is important for cancer stem cells. At the intersection of obesity, stem cells and tumor microenvironment is adipose tissue - might stem cells in adipose tissue due to poor prognosis in obese patients
The group began by examining cancer cells found in adipose tissue of a mouse model of leukemia. Rather than wait for the mixture of normal cancer cells with cancer stem cells, the group found that adipose tissue was enriched for cancer stem cells. No sneaky thieves were humble them - it is the master thieves of cancer stem cells that have exploited the cave adipose tissue thieves. Not only was there an abnormally high ratio of stem cells in adipose tissue, but these stem cells used another energy source that cells in the microenvironment of bone marrow stem - suitably, these stem cells in the adipose tissue energized their survival and growth with fatty acids, energy production by the method of the oxidation of fatty acids. In fact, these stem cells from adipose tissue actively signal the fat to undergo a process called lipolysis, which releases fatty acids into the microenvironment
"The basic biology was fascinating: the tumor adapted to the local environment to satisfy. " Jordan said.
Finally, when the group challenged these cells with chemotherapy, they discovered that the stem cells in fat tissue that had changed their energy source for the fatty acids were more resistant than the cells outside this tissue stem. When Ye, Jordan and colleagues examined samples of human leukemia, they found similar characteristics in mice models -. specialized cells to use fatty acids for energy were more resistant to chemotherapy
"Maybe in the context of chemotherapy treatment, these stem cells in adipose tissue might be more difficult to kill the cells in the bone marrow stem, "Ye said.
If further work is on this assumption, it could help explain why poorer outcomes in obese patients. the group plans to pursue studies with mouse models of obesity variable, which could shed light on whether more fat provides more power or a larger cave "thieves for cancer stem cells bypass treatment .
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