(Press-News.org) HOUSTON -- ( March 24, 2015 ) -- An experimental drug that attacks brain tumor tissue by crippling the cells' energy source called the mitochondria has passed early tests in animal models and human tissue cultures, say Houston Methodist scientists.
As reported on the cover of the April 2015 ChemMedChem (early online), Houston Methodist Kenneth R. Peak Brain & Pituitary Tumor Center Director David S. Baskin, M.D., and Peak Center Head of Research Martyn Sharpe, Ph.D. designed a drug called MP-MUS that destroyed 90 to 95 percent of malignant glioma cells, yet in other experiments did not seem to adversely affect healthy human brain cells (in vitro). This compliments a soon to be published extensive study showing the same drug can treat human brain cancer grown in the brains of mice. Researchers hope to begin testing the drug in human clinical trials in 2016 or 2017
"We are very optimistic that we'll get there," said Baskin, also Vice Chair of the Department of Neurosurgery at Houston Methodist Hospital. "Our past work has shown that MP-MUS has very low toxicity until it gets into tumor cells. Once it arrives, it is changed to its active form, doing a lot of damage where we want it to, leaving healthy brain cells alone -- a bit like a 'smart bomb.' To our knowledge, this is the first known example of selective mitochondrial chemotherapy, which we believe represents a powerful new approach to brain cancer."
Medical options for brain tumor patients are woeful, Baskin said. "It's a horrible diagnosis. Because of where the tumors are located, and because of the way they can infiltrate healthy tissue, surgery is often not helpful long term. The most effective chemotherapy drug available right now, temozolomide, only extends life from 9 to 15 months, and patients' quality of life during that period isn't very good."
For that reason, Baskin said, he and researchers around the world have been looking for new treatment approaches, such as vaccines intended to aid the body's immune system's recognition and removal of tumor cells, gene therapy and, in the present case, targeting tumor cell mitochondria.
Gliomas (a type of brain tumor) develop from brain cells called astrocytes. Gliomas account for as much as 20 to 30 percent of all tumors of the brain and central nervous system.
Mitochondria are often referred to as the "powerhouses" of cells -- including misbehaving cancer cells -- because they help cells create energy. In cancer cells this feature is partially switched off, causing cells to rely on other systems that generate energy. The numerous pill-shaped mitochondria in each cell perform a number of other crucial functions, however, and even cancer cells cannot grow and divide without healthy mitochondria.
As luck would have it, an enzyme called MAO-B is over-expressed in brain tumor cells, which is the target of MP-MUS. This means that healthy cells are only exposed to low levels of MP-MUS and their mitochondria to very low levels of P+-MUS, Baskin says. On the other hand, in tumor cells the vast majority of the pro-drug is converted into P+-MUS, which essentially traps the drug inside their mitochondria where it attacks the mitochondrial DNA.
"We found that we could achieve profound effects with MP-MUS at very low concentrations, around 75 micromolar," said Baskin, Professor of Neurological Surgery, Weill Cornell Medical College. "By contrast, temozolomide must be used at concentrations two to three times that to be of any use to patients. Our approach is designed to capitalize on what is going inside the cells. Tumor cells have much more MAO-B, and when challenged, make even more MAO-B as a sort of defensive response. We hope that we are one step ahead of the cancer cells, as we are using that very fact to kill them."
The researchers reported MP-MUS's toxicity to healthy cells remained low at concentrations as high as 180 micromolar. This information will be useful to the researchers as they consider safety and efficacy trials in human patients.
Houston Methodist and Baskin and Sharpe entered into an agreement with Virtici, LLC to develop MP-MUS and are currently preparing toxicology studies which are required prior to clinical trials.
INFORMATION:
Also contributing to the ChemMedChem paper Junyan Han, Ph.D., and Alexandra Baskin, a student at St. Johns School. Funding the project were the Donna and Kenneth R. Peak Foundation, the Kenneth R. Peak Brain and Pituitary Center at Houston Methodist Hospital, the Taub Foundation, the Blanche Green Estate Fund of the Pauline Sterne Wolff Memorial Foundation, the Verelan Foundation, the Houston Methodist Hospital Foundation, the Dunn Foundation, and the American Brain Tumor Association.
ChemMedChem is a sister journal of Angewandte Chemie and is published by Wiley. The journal's impact factor was rated 3.0 in 2013 by the Institute for Scientific Information.
To speak with Dr. Baskin, please contact Gale Smith, Houston Methodist, at 832-667-5843 or gsmith@houstonmethodist.org.
While human clinical trials have not yet begun for MP-MUS, Houston Methodist Neurological Institute doctors are overseeing participation in a number of clinical trials related to gliomas and glioblastomas. The Kenneth R. Peak Brain and Pitutary Tumor Center provides highly personalized and specialized care for all patients with Brain tumors For more information, please visit http://www.houstonmethodist.org/clinicaltrials, and http://www.houstonmethodist.org/peakcenter.
Dallas, TX (March 24, 2015) - John Rodakis, the parent of a child with autism was not looking to launch an international investigation into the microbiome (the collection of microorganisms that live on and in us) and autism, but, as he describes in his newly published article in the scientific journal Microbial Ecology in Health and Disease, when his young son's autism unexpectedly and dramatically improved while taking an antibiotic for strep throat, he began a quest to understand why.
Following the surprise improvement, Mr. Rodakis, who in addition to being a parent ...
DENVER, March 24, 2015 -- Chocolate has many health benefits -- it can potentially lower blood pressure and cholesterol and reduce stroke risk. But just as connoisseurs thought it couldn't get any better, there's this tasty new tidbit: Researchers have found a way to make the treat even more nutritious -- and sweeter.
They will describe their research here today at the 249th National Meeting & Exposition of the American Chemical Society (ACS), the world's largest scientific society. The meeting features nearly 11,000 reports on new advances in science and other topics. ...
DENVER, March 24, 2015 -- A new weapon in the war against type 2 diabetes is coming in an unexpected form: fat. Researchers have discovered a new class of potentially therapeutic lipids, called fatty-acid esters of hydroxy fatty acids (FAHFAs). These lipids are found at lower levels in people with insulin resistance, a risk factor for type 2 diabetes, compared with those who don't have the condition. Administering FAHFAs to diabetic mice improved their glucose metabolism and insulin secretion, opening a surprising avenue for the development of novel medications for the ...
DENVER, March 24, 2015 -- The recent increase in natural gas production could provide a bridge to a lower carbon future because it generates half the carbon dioxide (CO2) of coal when burned. However, natural gas that is leaked into the atmosphere could speed global warming and climate change. That's because its primary component, methane, is a much more powerful greenhouse gas than CO2. Understanding the leakage rate is critical to assessing the environmental benefit of natural gas, but there is much controversy, debate and confusion among scientists and policy-makers ...
LAS VEGAS--Osteoporosis is a disease of progressive bone loss affecting more than 44 million Americans and contributing to an estimated 2 million bone fractures each year. A new study presented today at the 2015 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) found that routine bisphosphonate treatment of women over 65 who sustain a distal radius (wrist) fracture--one of the most common fractures associated with osteoporosis--could significantly reduce the risk for additional fractures, primarily hip fractures, but at an estimated cost of more than ...
LAS VEGAS--New research presented today at the 2015 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) found that most child pedestrian injuries involving a motor vehicle occurred while children were unsupervised, near schools and bus stops, and in the spring months during the afternoon and evening hours.
Pedestrian injuries are among the leading causes of pediatric deaths in the U.S. In 2012, 557 child and young adult pedestrians under age 20 were killed by motor vehicles in the U.S. and 22,000 were injured, according to the National Highway Traffic ...
LAS VEGAS--Thanks to improved surgical, pain management and rehabilitation procedures, patients who undergo a total hip replacement (THR) may be able to safely drive as early as two weeks following surgery, according to new research presented today at the 2015 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).
Each year, more than 322,000 patients undergo hip replacement surgery in the U.S. Previous studies, conducted more than a decade ago, recommended between six and eight weeks of recovery before driving; however, recent advances in surgical treatment ...
LAS VEGAS--Diabetes and previous joint pain, along with a patient's overall physical health status, may predicts arthritis pain with nearly 100 percent accuracy, in new research presented today at the 2015 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).
An estimated one out of five adults is living with an arthritis diagnosis, according to the U.S. Centers for Disease Control and Prevention (CDC), and the number is expected to rise from 52.5 to 67 million by 2030. Arthritis means "inflammation of a joint." In osteoarthritis, the most common type ...
LAS VEGAS--Chronic low back pain can limit everyday activities, including sex. New research presented today at the 2015 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS), found that 70 percent of patients consider sexual activity "relevant" to their life quality, and patients who receive surgical treatment for spinal spondylolisthesis (DS) and spinal stenosis (SS)--common degenerative conditions most often occurring in older adults--were twice as likely to report no pain during sex.
"Our current research sheds light on the effect that spinal surgery ...
LAS VEGAS--While men and women have similar levels of improvement following total knee replacement (TKR) surgery, men have higher levels of function before and after TKR, according to new research presented today at the 2015 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).
According to the Agency for Healthcare Research and Quality, more than 600,000 knee replacements are performed in the U.S. each year. In 2012, 393,345 women and 237,896 men underwent TKR, most often to alleviate the pain and immobility associated with late-stage arthritis. While ...