Huge leap in the fight against cancer – a vaccine seems a reality

Human T Cell (also called T lymphocyte) - Photo by: NIAID - Source: Flickr Creative Commons

Research teams from the University College London Cancer Institute (UCL) made an earthshaking discovery in learning how the genetic differences in cancer cells can be used to destroy them. Scientists found several cellular targets that may “teach” the immune system how to recognize tumor cells and annihilate them, paving the way for future cancer vaccines and personalized cancer immunotherapy.

Immunotherapy to fight cancer

Immunotherapy may represent the future in the fight against cancer, due to the inherent ability of the immune system to track down and destroy tumor cells. Modern chemotherapy drugs are, in fact, unable to distinguish between “good” and “bad” cells, and are often very detrimental to the patient’s health. A large portion of the new cancer research did, in fact, focus on finding new strategies to help white blood cells focus on the right cellular targets, in order to eliminate cancer cells. T cells can understand whether a cell is a sane or a tumor one, in a similar fashion to the way they recognize and attack bacteria and virus-infected cells.

All cells possess several molecular targets called “antigens” that bind to specific portions of the T cell, telling the immune system if they’re dangerous for the organism. They’re a sort of “personal ID” that the white blood cell policemen use to identify various types of cells and destroy them in the earliest stage of tumor growth. However, as the tumor keeps growing, cancer cells learn new techniques to avoid detection by the immune system, significantly reducing its ability to fight them off. Tumor cells keep mutating, adding so many layers of genetic complexity in their antigens, that T cells can’t keep up with them.

The study teaches white blood cells how to recognize cancer cells

The research funded by the Rosetrees Trust and the Cancer Research UK, and has been published in the journal Science. Scientists found a new method to improve the recognizing ability of T cells, by mapping hundred of genetic variations of these mutations. Researchers took samples from 200 patients affected by lung cancer, using data from The Cancer Genome Atlas (TCGA). Although antigens keep being mutated as cancer grows, scientists were able to identify what the earliest mutations were. Instead of looking at all the branching that cancer cells add, layer by layer, to their antigenic portions, the research team focused on the “trunk” antigen that flags a given cell as a tumor one.
Thanks to this outstanding discovery, it is now possible to select those T cells that are able to recognize the earliest cancer cell strains. These T cells can be harvested and artificially multiplied in a laboratory, and then reinjected in the patient’s body. This strategy could be repeated several times, to provide patients with a fresh and efficient army of “policemen” that can easily recognize tumor cells, regardless of their new mutations. On the other hand, it will be possible to select the original tumor antigens to engineer cancer vaccines, which could be used to “teach” the immune system what their true enemies are.

This new research study may help improve our understanding of the effects of immune system on cancer, giving new hopes of finding new therapies to those that were previously considered as untreatable.

Article by Dr. Claudio Butticè, PharmD.

REFERENCES

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