Appearing online ahead of print in Nature Medicine, the researchers report the identification of a small protein that specifically recognizes tumors responding to chemotherapy. They show that the protein, when tagged with a light-emitting molecule, can be used to visualize cancer response in mice just two days after starting therapy.
Improved monitoring of tumor response could help customize patient treatment and also speed up the development of new cancer drugs, said senior investigator Dennis Hallahan, M.D., the Ingram Professor of Cancer Research and chair of Radiation Oncology at Vanderbilt University Medical Center.
Currently, response to chemotherapy is determined by measuring changes in tumor size with imaging techniques like CT (computed tomography) and MRI (magnetic resonance imaging).
“It takes two to three months of cancer therapy before we can determine whether the therapy has been effective for a patient,” he said. “If we can get that answer within one to two days, we can switch that patient to an alternative regimen very quickly.”
Rapid assessment of tumor response is especially important now, Hallahan says, given recent advances in molecular targeted therapies – chemotherapy medications that specifically interfere with the growth and proliferation of cancer cells while avoiding damage to healthy cells.
“We now have so many molecular targeted drugs to choose from, and that number is growing every year, so we are now at a point where a patient can be switched from one regimen to another,” he said. “But we need the tools to make the decision to use an alternative therapy with the patient.”
To find a rapid and noninvasive method to assess cancer response to these therapies, Hallahan focused not on tumor size, but molecular and cellular changes in responding tumors.
From a panel of billions of protein fragments, or peptides, Hallahan and colleagues identified one that specifically bound to tumors responding to therapy. To this peptide, they attached a light-emitting molecule and injected these labeled peptides into mice that had been implanted with human tumors.
Using specialized imaging cameras that detect light in the near-infrared range (invisible to the human eye), the investigators saw that tumors responding to therapy were “brighter” than non-responding tumors. The peptide detected response in a wide range of tumors – brain, lung, colon, prostate and breast – within two days of initiation of treatment.
“The key word here is ‘days,’” Hallahan said. “This will allow us to minimize the duration of treatments with ineffective regimens in cancer patients.”
The next step will be to move the technology into humans. The imaging technique used in mice (near-infrared) is not sensitive enough to penetrate deeply into human tissues, so the researchers are adapting the technology to an imaging modality commonly used in humans, called PET (positron emission tomography).
“This imaging peptide will enter clinical trials within about 18 months,” Hallahan said. “The purpose, when we bring it into people, is to ask a very simple question: can we image responding cancers in people as well as we can in mice?”
If so, he says that he suspects that such molecular imaging methods could help accelerate the development of new chemotherapeutic drugs.
“In the pharmaceutical industry, we’ll have a patient on a drug for months before we can re-evaluate the size of the tumor,” Hallahan said. “If we can get that answer within a couple of days, it will speed cancer drug development in the early phases of clinical trials.”
Craig Boerner | EurekAlert!
Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel
Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)
The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.
Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
25.05.2018 | Event News
02.05.2018 | Event News
13.04.2018 | Event News
25.05.2018 | Event News
25.05.2018 | Machine Engineering
25.05.2018 | Life Sciences