Nanoparticles will evaluate the effectiveness of cancer treatment
The ability to assess the effectiveness of antitumor therapy in a timely manner means the possibility of making personalized adjustments to the course of therapy and improving the patient's quality of life. However, modern methods, such as positron emission, computer and magnetic resonance imaging, usually allow you to determine whether the tumor is shrinking in response to treatment, only after several courses of therapy.
Researchers at Boston's Brigham and Women's Hospital, working under the guidance of Dr. Shiladitya Sengupta, have proposed a new approach that allows evaluating the effectiveness of chemotherapy as early as 8 hours after the start of treatment. This technology can also be used to monitor the effectiveness of immunotherapy.
The technology is based on the fact that when a cell dies, the enzyme caspase is activated. The authors have developed polymer nanoparticles that deliver not only the drug to the tumor, but also a "recording element" – a compound that emits a green glow in the presence of caspase.
After that, they analyzed the ability of this system to distinguish therapy-sensitive tumors from insensitive ones. To do this, it was tested on preclinical models: nanoparticles loaded with the widely used antitumor drug paclitaxel were tested on prostate tumors, and nanoparticles carrying an immunotherapy drug specific to the PD–L 1 ligand were tested on melanomas. At the same time, in the samples of tumors sensitive to paclitaxel, the fluorescence intensity was approximately 4 times higher than the fluorescence intensity in tumors insensitive to the drug. Also, in melanoma samples, a significant increase in the fluorescent signal was observed 5 days after exposure to nanoparticles loaded with an immunopreparation.
According to the authors, the new technology will help to directly visualize and evaluate the response of tumors to both chemo and immunotherapy. They explain that modern methods of evaluating the effectiveness of treatment are based on the analysis of the metabolic status or the size of the tumor and in some cases do not allow to determine the effectiveness of an immunotherapeutic agent, since the size of the tumor may even increase due to infiltration by attacking immune cells. At the same time, the particles developed by the authors can provide reliable information about the death of cancer cells.
Currently, the researchers plan to develop nanoparticles suitable for use in clinical practice, and subsequent testing of their safety and effectiveness, which is a mandatory stage preceding the start of clinical trials.
Article by Ashish Kulkarni et al. Reporter nanoparticle that monitors its anticancer efficacy in real time is published in the journal Proceedings of the National Academy of Sciences.
Evgenia Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Brigham and Women's Hospital: New Nanoparticle Reveals Cancer Treatment Effectiveness in Real Time.
30.03.2016