Obesity Weight Loss Surgery

Obesity / Weight Loss Story

Viruses Zap Tumors, Not Healthy Tissue

Scientists have developed a new virus through genetic engineering that invades and bursts cancer cells while leaving healthy cells entirely alone. Researchers at the Mayo Clinic engineered the genome of the oncolytic (or cancer dissolving) virus to recognize the so-called microRNAs of normal tissue and therefore pass by those cells, infecting only cancerous tissue. MicroRNAs are short snippets of 20 or so nucleotides that don't code for proteins but rather seem to have the effect of regulating gene expression.

"Our findings demonstrate a new tool for molecular medicine that should also help allay concern over the use of viruses as a therapeutic delivery system," said Stephen Russell, Mayo physician-scientist and lead author of the study, in the journal Nature Medicine.

Russell and his colleagues say that the mice in their experiment, which were suffering from melanoma, or malignant skin cancer, were exposed to the engineered virus and completely cured of established tumors, without suffering any side effects.

 The research team specifically looked at muscle tissue, and found that the virus completely avoided it, focusing only on the cancer tissue. Unengineered viruses attack many different types of tissue. Thus, it's not surprising to see the variety of symptoms usually associated with viral disease.

 But, since viruses are increasingly being used as vaccines, cancer therapeutics and gene-therapy delivery agents, it's becoming urgent that ways be found to restrict viruses' activities to the target tissues, which the current research seems to have succeeded in doing. Russell's work, therefore, may be a step toward safer vaccines, more effective gene therapy and better cancer relief.

Related Stories