Gene Therapy to battle against cancer

Scientists for the first time have used gene therapy to battle with the most pernicious skin tumors. The development is being seen as milestone in the field of cancer treatment.

Methods like radiation, surgery and chemotherapy hold a prominent place in treatment of cancer, yet, new discoveries are being added in the already existing treatments and thus expanding the horizons.

Gene therapy is the insertion of genes into an individual's cells and tissues to treat cancer. This therapy typically aims to supplement a defective mutant allelomorph with a functional one.

Although the technology is still in its infancy, it has been used with some success. Recent reports showed its result being significant, when two out of the 17 patients were cured, just after 18 months of the therapy.

For many years, research is being carried out in this field; however, it is the current development which has the potential to be applied to common cancers.

Scientists at the National Institutes of Health (Bethesda, MD) have successfully treated metastatic melanoma in two patients using killer T cells genetically retargeted to attack the cancer cells. This study constitutes the first demonstration that gene therapy can be effective in treating cancer.

Rosenberg and colleagues took out the white blood cells called T cells from the patient’s body and altered it to produce a receptor that can stick itself with tumors. The receptors, known as T cell receptors trigger the white blood cells, which defeat the cancer cells.

The scientists are still trying to revise their findings, since the treatment didn’t cure all the 17 patients. Above all, previous gene therapies show that post treatment, patients are likely to develop leukemia. The long term safety of the therapy is still a question mark.

A form of immune deficiency called Adenosine deaminase (ADA) deficiency was the first disease to be treated with a gene therapy approach in humans in the early 1990's. Since then, gene therapy is being progressing, but it is bound with limitations and side effects. The present aim of the scientists is to develop it without any flaw.

Rosenberg said the therapy might not have worked because the studies, conducted two years ago, used a gene that produced a relatively weak T cell receptor.

He said that the T cells being used now are more potent, thus offering better responses and his team is however searching for ways to enhance the current therapy so larger numbers of the altered T cells can survive and go forward in expressing their receptor genes.

The research is an important step in which the power of immune system to fight cancer has been acknowledged.