Researchers at the University of California, San Diego School of Medicine have identified a new biomarker that predicts whether glioblastoma – the most common form of primary brain cancer – will respond to chemotherapy. The findings are published in the July print issue of Oncotarget.
"Every patient diagnosed with glioblastoma is treated with a chemotherapy called temozolomide. About 15 percent of these patients derive long-lasting benefit," said Clark C. Chen, MD, PhD, vice-chairman of Academic Affairs, Division of Neurosurgery, UC San Diego School of Medicine and the study's principal investigator.
"We need to identify which patients benefit from temozolomide and which another type of treatment. All therapies involve risk and the possibility of side-effects. Patients should not undergo therapies if there's no likelihood of benefit."
To pinpoint which patients were most likely respond to temozolomide, the researchers studied microRNAs that control the expression of a protein called methyl-guanine-methyl-transferase or MGMT. This protein dampens the cancer-killing effect of temozolomide. Tumors with high levels of MGMT are associated with a poor response to temozolomide therapy.
The scientists systematically tested every microRNA in the human genome to identify those that suppressed MGMT expression, with the expectation that high-levels of these microRNAs in the tumor would predict improved therapeutic response to temozolomide.
"We showed that a signature of the MGMT-regulating microRNAs predicted temozolomide response in a cohort of glioblastoma patients. Validation of these results should lead to diagnostic tools to enable us to determine which patients will benefit most from temozolomide therapy," said Chen.
In the study, the scientists also discovered that injection of the MGMT-regulating microRNAs into glioblastoma cells increased tumor sensitivity to temozolomide treatment.
"These findings establish the foundation for microRNAs-based therapies to increase the efficacy of temozolomide in glioblastoma patients," said lead author, Valya Ramakrishnan, PhD, postdoctoral researcher, UC San Diego School of Medicine.
Contributors to this paper included Deepa Kushwaha, Dipanjan Chowdhury and Kimberly Ng of Dana-Farber Cancer Institute; Jann Sarkaria of Mayo Clinic; Tao Jiang of Tiantan Medical Center; and Tyler Steed, Thien Nguyen, Diahnn Futalan, Johnny Akers and Bob S. Carter of UC San Diego.
Funding for this research came, in part, from the Sontag Foundation, Burroughs Wellcome Foundation, Kimmel Foundation, and the Forbeck Foundation.
Jackie Carr | Eurek Alert!
How Invasive Plants Influence an Ecosystem
28.07.2016 | Albert-Ludwigs-Universität Freiburg im Breisgau
Perseus translates proteomics data
27.07.2016 | Max-Planck-Institut für Biochemie
Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.
To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...
A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology
On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...
Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.
While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.
Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.
Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...
Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases
Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...
15.07.2016 | Event News
15.07.2016 | Event News
11.07.2016 | Event News
28.07.2016 | Information Technology
28.07.2016 | Materials Sciences
28.07.2016 | Earth Sciences