Study Showing Stem Cells Destroying Their Own DNA
All cells contain DNA made of 46 chromosomes which break into pieces when exposed to ultraviolet light and some chemicals. The process has been traditionally considered harmful, and to be the cause of cell death and series of diseases such as cancer if the damage was not repaired in a short period of time. However, the new research that was conducted by Dr. Lynn Megeney and his team at the Ottawa Hospital Research Institute and the University of Ottawa turned the widely accepted theory on its head. The study that was published in Proceedings of the National Academy of Science recently will probably dramatically change the view of the scientists on tissue formation, role of stem cells and development of diseases such as cancer.
Megeney and his group were researching the role of stem cells in the process of muscle fiber formation in 2002 when they discovered that formation of new muscles was closely tied to cell death. They proved the connection by removing or blocking the caspase 3, a protein which promotes cell death. Absence of the protein resulted in cessation of production of muscle fibers by the stem cells. The results of the 2002 study were very controversial when published but many researchers reported about the link between cell death and formation of new muscle fibers since then. However, the ability of proteins responsible for cell death to induce muscle fiber formation remained a mystery.
Dr. Megeney and his group said they have managed to solve the mysterious role of proteins that promote cell death in the process of formation of new muscle fibers. They have shown that caspase 3 activates a protein responsible for cutting of DNA which in turn stimulates the gene that is crucial for the formation of new muscle fibers. Thus the results of the study have shown that the stem cells actually destroy their own DNA in order to induce production of new tissues.
Subscribe to the comments for this postDifferentiation of iPS Cells in Comparison with Human Embryonic Stem Cells
The controversy of human embryonic stem cell research forced the regenerative science into further research of the iPS cells which are thought to have the same potentials as embryonic stem cells derived from the unused human embryos. However, a study that was published in the Proceedings of the National Academy of Sciences on February 15 in 2010 has shown otherwise. The professor at the University of Wisconsin-Madison School of Medicine and Public health and senior author of the study, Su-Chun Zhang said that differentiation of the iPS cells was less efficient than of human embryonic stem cells and that the iPS cells are less predictable than the controversial embryonic stem cells which can differentiate into all 220 human cell types.
Su-Chin Zhang and his team led by Baoyang Hu have conducted a comparison study using five embryonic cell lines and twelve iPS cell lines to determine the capability of differentiation of both cell lines into the brain cells. The team has discovered that the differentiation of iPS cells was less efficient than embryonic cell differentiation due to unknown factors which might limit the use of iPS cells for both the study of human diseases and therapeutic purposes such as transplantation of the cells. However, the researchers have also discovered that genes do not affect the ability of the iPS cells to differentiate as it was expected. Presence and absence of genetic factors have been shown not to affect the differentiation ability of the iPS cells. For that reason Zhang’s team believes that the technology used for generation of iPS cells requires further improvements.
The study has shown that further research is necessary to determine why differentiation of iPS cells is different and unpredictable. But the iPS cells remain very useful for many applications including testing of potential treatments and new drugs.
Stem Cell Science and Fat Transplantation
Cytori Therapeutics, Inc, a regenerative medicine company has developed an effective procedure of breast implantation in women by using the stem cell science in combination with the company’s procedure known as Celution 800. Latter is used in Europe and other parts of the world since year 2007 but the procedure is still waiting to be approved by the Food and Drug Administration (FDA) in the United States.
The company has successfully combined stem cell science and fat grafting which may significantly improve the outcome of breast implantations in women both for therapeutic and aesthetic purposes. The procedure which has also great potentials in cosmetic and reconstruction surgery is still being developed and bases on enlargement of fat cell density before being implanted. The fat stem cells may be used by the surgeon to stimulate the fat tissue that is a part of the operation and is believed to induce growth of blood vessels and enrichment of transplanted fat cells. In addition, the structure of the cells within the transplanted fat tissues becomes sturdier which reduces the risk of complications and improves the overall success rate of re-growth of the missing tissue.
Intermediate results of the procedure were presented at the 32nd Annual San Antonio Breast Cancer Symposium in December 2009 and have shown that over 70% of women and over 80% of physicians were satisfied with the results of the procedure involving stem cells 6 month later. The company also underlined that the procedure involving stem cells may not result in improvement of fat transplantation in patients with breast cancer that underwent radiation therapy after mastectomy (partial or complete breast removal) and lumpectomy (surgical removal of the tumor). Lesser success rate of the procedure in patients with breast cancer that underwent radiation therapy can be assigned to the breast tissue damage that was caused by the radiation therapy and difficulties in grafting.
New Bill Against the Ban of Embryonic Stem Cell Use for Research
The supporters of the use of human embryonic stem cells for research, the South Dakotans for Lifesaving Cures have announced to seek a repeal of the South Dakota’s ban on the research at the Legislature. Similar attempt has failed in year 2009 because it was rejected by the state Senate with 20 to 14 against the repeal. The main problem seems to be the compare of embryonic stem cell use with destruction of human life and inadequate evidence about potential benefits of the research. In addition, the use of embryonic stem cell for scientific research is often closely tied with fear that it will lead to cloning although the supporters of the research have clearly stated themselves against cloning and oppose any change of the law that prohibits cloning. The bill that is going to be introduced to the Senate will contain clearer statements about the support to the prohibition of cloning as well as restriction of use of embryonic stem cells for research.
The co-chairman of the South Dakotans for Lifesaving Cures, David Volk is very optimistic and believes that the Senate will accept their bill although Dave Knudson from the Republican Party expressed his doubts about the group’s success. The supporters of the use of embryonic stem cells for scientific research can count on Scott Heideprien from the Democratic Party who has voted for the repeal that failed in 2009 and has announced his support to the new bill with an argument that restriction of embryonic stem cell for research does not protect life because unused embryos are discarded.
Both parties support the use of mature stem cells derived from bone marrow in adults and children for research on diabetes and other medical conditions but they disagree when it comes to human embryonic stem cells. Latter come from an egg that was fertilized in a laboratory to help the couples with conception difficulties.
The Buck Institute for Age Research is to Build a $41 million center for research of stem cells
The Buck Institute for Age Research has received an award and starting capital of $20,5 million for the construction of a $41 million center for research of stem cells by the California Institute for Regenerative Medicine in May 2008. Due to financial crisis the Buck Institute was not able to raise its award that is required to complete the planned research center in Novato. Despite that Dr. Charles Epstein, the institute’s chairman of the board of trustees has announced that the institute’s board decided to proceed the plans for the construction of the research center even if the institute does not receive $15 million in federal funds for stimulation.
Dr. Epstein admits they will have difficulties without the federal stimulus money because it is not easy to get $20 million from anyone during the recession. In case if the institute does not get a larger amount of stimulus funds it will try to collect the required sum at the philanthropic organizations and private donors. Dr. Epstein also stated that the Buck Institute is prepared to loan the necessary money to complete the construction of their research center.
The 65,600 square feet research center will be built next to the institute’s headquarters in Novato. The plan made by I. P. Pei foresees five buildings on 335,000 square feet and has almost all the necessary papers allowing its construction. According to Ralph O’Rear, the institute’s vice president for facilities and planning the construction of the center will start at the end of March or April and will resemble the institute’s building that are already in existence when completed. It will house dozen labs, cell and tissue storage facilities, offices for administration, a gym, library, conference room and food service. O’Rear also stated that the institute is considering construction of a shell building to rent it to interested parties.
Development of Method to Determine Ethnic Background of the Stem Cells
The stem cell science has achieved an enormous progress and has a lot of potentials for treatment of variety of diseases and disorders. Stem cells can be used to replace or restore the damaged tissues but the overall success has been shown to greatly depend on ethnic background of the receiver and the donor of stem cells, just like in case or organ donor and receiver. Thus development of method to determine the ethnic background of stem cells by the scientists and researchers of The Scripps Research is major step forward in the stem cell science.
Accessibility to genetically different cell lines will significantly improve the safety and efficacy of transplantation of the tissues and certain medications as well as the overall success of stem cell treatment. The scientists at The Scripps Research have developed an easy and inexpensive method called the SNS genotyping to determine the ethnic background of the donors of stem cells. Asking the donors about their ethnic origin does not provide a reliable information because many people have an ancestor with a different genetic background without being aware of it. In addition, the researchers have also discovered that a country of origin does not make the determination of ethnic background any easier.
The researchers have used 47 samples of human embryonic stem cells that were gathered from laboratories from all over the world and 5 iPS cells. They have come to the conclusion that the majority of samples had a Caucasian and East Asian ethnic background and that only few were of African origin. For that reason the scientists have developed a completely new cell line of Yoruba origin, a western African ethnic group.
The research has been published in the journal Nature Methods in January 2010 and was financed by National Institutes of Health, California Institute for Regenerative Medicine, and Bill and Melinda Gates Foundation.
Pfizer Buying Rights for Treatment with Stem Cells
The use of stem cells for therapeutic purposes has attracted a lot of attention of the pharmaceutical industry and the best evidence for that is the announcement of Pfizer buying rights for the development of stem cells from Athersys. The number one pharmaceutical company in the world has signed an agreement with the biotechnology company based in Cleveland which gives Pfizer the right to develop and use the Athersys’ stem cells for treatment of inflammatory bowel disease, in first place of Crohn’s disease and ulcerative colitis. The exclusive right will cost Pfizer of $6 million at the beginning and about $105 million over the following years. The sum Pfizer is prepared to pay clearly reveals the interest of pharmaceutical industry in stem cell technology as well as the fact that the use of stem cells for therapeutic purposes requires further studies and research.
The ability of stem cells to form various tissues within the body has great potentials in the future treatment of various medical conditions. The stem cells developed by Athersys from bone marrow known as MultiStem still require further clinical tests in patients with inflammatory bowel disease and are currently being tested in humans as a heart attack and cancer therapy. Stem cells might be very useful as a replacement for damaged tissues but Pfizer and Athersys foresee the use of stem cells to encourage the body’s self-healing abilities.
Stem cells from mature tissues such as MultiStem do not arise as much controversy as stem cells obtained from human embryos but the therapy still raises a lot of eyebrows in the scientific community.
In collaboration with University College London, Pfizer also works on use stem cells for treatment of age related macular degeneration and develops a treatment for diabetes by using embryonic stem cells with Novocell, a San Diego based company.
For laymans: Stem cells explained
Stem cells and all the things connected with them can get a little confusing for a layman. Many people simply don’t understand what are stem cells, what do they actually do, and where do they come from — even after reading a lot of information about them. Therefore, we present you a couple of videos that we stumbled upon, which explain stem cells in very simple terms. Enjoy.
Stem Cells and Children’s Brain Tumor
Medulloblastoma is the most common type of children’s brain cancer. It most often affects children between the ages of three and eight but it can also occur in young adults. So far, the scientists knew relatively little about medulloblastomas and why some patients responded poorly to the treatment. However, the new research conducted by the scientists at Queen Mary, University of London led to an important discovery.
The research about the role of stem cells in children’s brain tumor was led by Silvia Marino, Professor of Neuropathology at Queen Mary, University of London. The results of the study published in Oncogene on January 12 in 2010 reveal that medulloblastomas can grow from a type of brain stem cells, known as neural stem cells. The scientists have also proven that the type of brain cancer is a distinctive form of the disease which means that it might require a new approach to the treatment.
Considering the challenge medulloblastomas pose when it comes to treatment the discovery of the researchers at Queen Mary, University of London is a major step forward. The findings of the Professor Marino and her team have shown that some of the children’s brain tumors develop from endogenous stem cells which is very important for the understanding of the aggressive form of medulloblastomas and for development of more effective treatment.
Professor Marino and her team studied stem cells from mouse brains that are equivalent to the neural stem cells in the human brain. They discovered that genes Rb and p53 that are known to play a role in cancer might function improperly in the brain stem cells allowing uncontrolled growth of these cells and their transformation into cancer cells. The researchers also found that the patients with aggressive form of the disease have the same genetic pattern of the tumor.
Chinese Regenerative Medicine and Controversy of Therapies Involving Stem Cells
Regenerative medicine is a combination of interdisciplinary researches, techniques and clinical applications that moves beyond the traditional transplantation therapies. It focuses on repair, replacement and regeneration of cells, tissues and organs damaged from disease, trauma, aging and congenital defects. There are several approaches to stimulate the body’s own healing abilities which may involve transplantation of stem cells, gene therapy, tissue engineering, soluble molecules, and manipulation of cell and tissue types.
According to the study of the MRC that was published in the UK journal Regenerative Medicine, China wants to become a leader in the field of regenerative medicine. The MRC’s claims also confirms the growing number of Chinese contributions to scientific journals in the field which are exceeded only by the US, German, Japanese and British experts.
The Chinese researchers have made a remarkable contribution to the science of regenerative medicine, while the Chinese government significantly enlarged the funds for stem cell research, tissue engineering and gene therapy. However, the Chinese international credibility has been and still is suffers because of administration dubious therapies involving stem cells in Chinese clinics. Although Chinese Ministry of Health requires evidence of safety and efficacy for all stem cell and gene therapies there are over 200 clinics all over China offering stem cell treatment for series of diseases such as ataxia, diabetes, multiple sclerosis, spinal cord injury, cerebral palsy, Parkinson’s disease and many others which have become increasingly popular outside China as well.
The International Society for Stem Cell Research (ISSCR) has strongly condemned therapies involving stem cells offered in the Chinese clinics, but the MRC found out that the number of foreign patients traveling to China is rapidly rising. Thus the treatment involving injection of cells from aborted fetuses at an institute in Beijing was received by approximately 1,000 foreigners from total 1,500 patients.