Veterinary college researchers awarded National Institutes of Health grant to expand study of poultry virus as human cancer treatment
February 13, 2008
Researchers on the Blacksburg and College Park, Md., campuses of the Virginia-Maryland Regional College of Veterinary Medicine have been awarded a major new grant from the National Institutes of Health to support innovative work that seeks to develop a treatment for cancer from a common avian virus.
This is the second major grant awarded to Drs. Elankumaran Subbiah of Blacksburg, Va.; assistant professor, Department of Biomedical Sciences and Pathobiology; and Siba Samal of College Park, Md., associate dean of the college’s University of Maryland campus, for the work aiming to create a cancer therapy from genetically altered Newcastle Disease virus.
According to the American Cancer Society, cancer accounts for nearly one-quarter of all deaths in the United States, exceeded only by heart diseases. It is estimated that 1.4 million new cases of cancer were diagnosed in 2007 alone.
The National Institutes of Health $430,000 R21 grant will allow Subbiah and Samal to build upon existing work that is focused on the use of reverse genetics to alter the Newcastle Disease virus to treat prostate cancer.
Reverse genetics is the process of generating a recombinant virus from cloned complimentary DNA or cDNA copy, explains Subbiah. Through the reverse genetics system, recombinant viruses can be designed to have specific properties that make them attractive as biotechnological tools, live vaccines, and cancer therapies. The change is achieved through the introduction of the desired changes in the cDNA, which are then transferred faithfully to the recombinant virus.
“This differs from the previous work in that the recombinant [Newcastle Disease virus] will be targeted against different types of proteases,” said Subbiah. “Different types of cancer cells secrete different types of proteases. We are tailoring the virus to match the type of protease secreted by the cancer cells.”
Normal, healthy cells have an interferon antiviral system that activates upon infection with the virus, thereby preventing replication of the virus, explains Subbiah. Cancer cells, however, have defective interferon antiviral systems, he said. [Newcastle] utilizes these defects to replicate specifically in the diseased cells. The replication of the virus generates apoptosis—also known as programmed cell death or cell suicide—in the diseased cell.
According to Subbiah, the use of poultry viruses as cancer therapy poses no threat to humans and several other oncolytic viruses are currently being explored to treat cancer. However, Subbiah’s work is the first to alter the Newcastle disease virus through a reverse genetic system for selective protease targeting. Oncolytic virus therapy has gained much attention recently as a result of the progress in understanding virus-host interactions and because currently available chemotherapy is not entirely satisfactory for several reasons, including the possibility of an individual’s development of resistance to drugs.
“We are excited about the endless possibilities that Newcastle disease virus offers to treat cancer,” said Subbiah.
Subbiah received his bachelor’s degree in veterinary science in 1984, master’s degree in veterinary science in 1989, and Ph.D. in veterinary microbiology in 1996 from the Madras Veterinary College in Madras, India; and he was boarded in virology from the American College of Veterinary Microbiologists in 2003. He was a research assistant professor at the Virginia-Maryland Regional College of Veterinary Medicine’s College Park, Md., campus prior to joining Virginia Tech in 2006.
Samal received his bachelor’s degree in veterinary science from Orissa Veterinary College (India) in 1976, his master’s degree in veterinary science from the Indian Veterinary Research Institute, and master of science and Ph.D. degrees from Texas A&M University. He joined the faculty at the University of Maryland in 1988, and is currently the associate dean of the Virginia-Maryland Regional College of Veterinary Medicine and chair of the Department of Veterinary Medicine at the University of Maryland in College Park.
The Virginia-Maryland Regional College of Veterinary Medicine (VMRCVM) is a two-state, three-campus professional school operated by the land-grant universities of Virginia Tech in Blacksburg and the University of Maryland at College Park. Its flagship facilities, based at Virginia Tech, include the Veterinary Teaching Hospital, which treats more than 40,000 animals annually. Other campuses include the Marion duPont Scott Equine Medical Center in Leesburg, Va., and the Avrum Gudelsky Veterinary Center at College Park, home of the Center for Government and Corporate Veterinary Medicine. The VMRCVM annually enrolls approximately 500 Doctor of Veterinary Medicine and graduate students, is a leading biomedical and clinical research center, and provides professional continuing education services for veterinarians practicing throughout the two states. Virginia Tech, the most comprehensive university in Virginia, is dedicated to quality, innovation, and results to the commonwealth, the nation, and the world.