A team of researchers at the University of Massachusetts Medical School, led by an Indian neuroscientist, has developed a non-invasive gene therapy to treat brain tumour. Currently, treatment for brain tumour or Gliobastoma (GBM) involves surgery, followed by radiation and chemotherapy with temozolomide. Still, complete surgical removal of tumour is nearly impossible, as these cells are also radio and chemotherapy resistant. Thus, tumour recurs in a few months after surgery and finally causes death. Even with the best of treatment, only 3% patients survive up to five years. One of the major difficulties to treat glioblastoma is the tumour cells are highly migratory and they travel long distances within the brain as single cell infiltrates and invades within other tissues. These single cell infiltrations are difficult to detect in the MRI scan and also almost indistinguishable from healthy tissues in the brain. Thus, it is impossible to remove the tumour completely in a surgery. Since the overall survival of a GBM patient post diagnosis is less than two years, medical scientists have been exploring therapeutic approaches to prevent recurrence of tumour. According to a report appearing in the Indian Science Journal, a team of scientists led by Dwijit Guha Sarkar of University of Massachusetts Medical School researched the possibility of such an approach and found a systemic delivery approach of viral vector mediated gene therapy injection in the blood, with Interferon beta (IFNb) gene. IFNb is a cytokine secreted from cells upon viral infection and activates several genes downstream. IFNb is a cytokine, which is a class of secreted proteins that play important immune functions in our body.
IFNb is naturally secreted from our body cells as a part of immune protective mechanism when there is a viral infection. It can modulate ~300 other gene expressions downstream and can activate many biochemical pathways. Interestingly, other than its role as immune-modulator, it has several anti-tumour functions. It can inhibit cancer cell division, prevents new blood vessel formation (angiogenesis) in tumour, can also sensitize some chemo-resistant tumour cells to some chemotherapeutic drugs. “In search for a new therapeutic approach, in this study we examined (in a mouse model) a method of gene therapy. We have implanted highly invasive and aggressive human glioblastoma tumour cells in the mouse brain. We allowed it to graft and grow. Then we treated these animals with our new gene therapy approach. We have used adeno-associated viral vector (AAV) mediated interferon-beta (IFNb) gene therapy.
