Cancer of the uterine cervix, also known as cervical cancer, is the second leading cause of cancer deaths among women in India. Almost one lakh women fall victim to the insidious disease every year in the country.
Hope in tumour antigen
But there is hope. Researchers at the New Delhi-based National Institute of Immunology (NII) have now extracted a tumour antigen named SPAG9 that promises to be a highly potent weapon against this type of cancer.
“The tumour antigen, which is expressed in reproductive tract cancers and a variety of malignancies, has proved successful in phase I trials. This means that it has been proved to be safe on human subjects. Phase II clinical trials are presently under way to gauge its efficacy. We hope to get positive results by next year,” says Dr. Anil Kumar Suri, NII director, in an interview.
The therapeutic vaccine based on the antigen is being tested among 54 patients at the Cancer Institute (WIA) at Adyar in Chennai. The trials are being conducted by a team of oncologists led by Dr. T. Rajkumar.
Invasion of foreign bodies such as bacteria or viruses usually trigger a volley of fighter-cells called T cells. They surround germs and fight them.
Each type of virus or bacteria requires specific antigen T cells. Vaccination primes the body to potential threats and keeps the arsenal of antigens ever ready to fight an invasion.
However, this cannot happen with cancer. Even though they are rogue elements, cancer cells are after all from within the affected persons themselves. The body’s immune system cannot normally recognise them as a ‘threat’. Therefore, they allow them to proliferate and spread all around the body.
Using immunotherapy
Immunotherapy is a new approach that exploits the body’s inner capability to put up a fight against cancer. Under the approach, either the immune system is given a boost or T cells are “trained’’ to identify recalcitrant cancer cells and kill them.
The NII scientists are using this strategy to develop the new weapon against cancer of the cervix. “We take cells called monocytes from the patient’s blood and modify them into what are called dendritic cells. These cells have efficient antigens to stimulate the ‘fighter’ cells, or T-cells, in the body. They are then primed with the tumour antigen SPAG9, for 10 days, and given back to the patients in the form of a vaccine. The ‘educated’ T cells are able to discriminate the cancer cells and put up a fight against them,” explains Dr. Suri.
Poor health, malnutrition and an unhygienic environment are the main cause behind the Human papillomavirus (HPV) infection that leads to cervical cancer. Normally our body has tumour suppressor genes and proteins which are able to suppress the formation of tumours. The cells in a tumour multiply uncontrollably with hardly any cell death.
NII has outsourced the manufacture of recombinant SPAG9 to Syngene International (Biocon Limited), Bengaluru. “If the trials succeed, it will be the first molecule identified in India and will be an example of translational research outcome. Our findings have opened new avenues for novel treatment modalities in battling the deadly disease of cancer worldwide,” says Dr. Suri. — India Science Wire
