Modified Avian virus against prostate cancer
A new method of treating prostate cancer with the help of an oncolytic virus, developed by scientists at the Virginia Polytechnic Institute, avoids all the adverse side effects associated with traditional methods of treating malignant diseases, including chemo- and hormone therapy.
As a therapeutic virus, the researchers chose the Newcastle disease virus (avian pseudochuma virus), which is fatal to chickens, but safe for humans. This virus is oncolytic, that is, it has the ability to destroy tumor cells, and has already demonstrated promising results in a number of clinical studies of treatments for different types of cancer. However, successful therapy requires multiple injections of large doses of the virus, since viral particles hardly penetrate into the tumor area and do not spread well through the tumor tissue itself.
The authors tried to solve this problem by modifying a protein that ensures the penetration of a viral particle into an infected cell by merging the virus envelope with the cell membrane. Proteins of this group are activated when cut by any of the enzymes belonging to the family of cellular proteases. The researchers modified the corresponding protein of the Newcastle disease virus in such a way that its cutting and, accordingly, activation became possible only under the action of a prostate–specific antigen - the most well-known marker of prostate cancer belonging to the protease family. This modification minimizes the loss of viral particles on their way to target cells.
Such a modified oncolytic virus has significant advantages over other methods of treating prostate cancer, since it does not cause adverse reactions characteristic of the use of chemotherapy drugs and suppression of testosterone secretion, and is suitable for the treatment of tumors resistant to hormone therapy. In earlier clinical studies, even the administration of very large doses of natural strains of the virus caused only mild flu-like symptoms in patients. Reducing the dosage due to the targeted action of the modified virus will also eliminate these minor side effects.
Currently, the modified virus is already ready for preclinical testing in animal models and, possibly, even for phase 1 clinical trials.
Article by R. Shobana et al. Prostate Specific Antigen Retargeted Recombinant Newcastle Disease Virus for Prostate Cancer Virotherapy is published in the Journal of Virology.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the American Society for Microbiology:
Virus Shows Promise as Prostate Cancer Treatment.
04.03.2013