Galery

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Scientists from the National Research Centre of Natural Sciences "Dimokritos" in collaboration with researchers from the University of Athens, University of Michigan (USA) and the University of Southampton (UK) have made a promising step forward in the field of cancer immunotherapy.

The research will be published in the prestigious Journal of the National Academy of Sciences of the United States "Proceedings of the National Academy of Sciences" (PNAS).

The research process is headed by Dr. Efstratios Stratikos from the Protein Chemistry Laboratory of the Institute for Nuclear and Radiological Research at the National Research Centre "Dimokritos" and it involves the Greek scientists Dimitris Georgiadis, Eftalia Zervoudi, Emmanuel Saridakis, Panagiota Kokala and Irini Mavridi.

Using the immune system of the patient (immunotherapy) is a promising alternative method of treatment in comparison with the chemotherapy for cancer treatment which is widely used today and which is often inefficient because of the low selectivity and the high toxicity of the substances used.

So far, however, the immunological therapeutic approaches have not yet brought the expected results at the clinical level. This is largely due to the fact that the scientists are not very well aware as to how the immune system can identify the cancer cells and how the cancer learns to avoid the attacks by the immune system.

In recent years, various studies have revealed that the cancer cells manage to avoid the attacks by the immune system by destroying the "signals sent" by each diseased cell. In the majority of the cases, similar signals, called antigenic peptides, can be destroyed by enzymes called aminopeptidase that reside inside the cell, the aminopeptidase ERAP1 being the most typical one.

As already shown, the blocking of this enzyme can result in activation of the immune system, destruction of the cancer cells and, ultimately, in the complete cure of the cancer tumours in laboratory animals. Although drugs known as inhibitors can block the aminopeptidase ERAP1 in theory, it turns out that, in practice, it is very difficult to create such active substances to combat the ERAP1.

Though the ERAP1 was discovered over 10 years ago, no research team in the world has announced that it has developed effective inhibitors for this enzyme. The success of the Greek and foreign researchers is that, after studying this enzyme for years, they have been able to create chemicals that block it efficiently, thus activating the production of antigenic peptides.

The scientists have proved, experimentally and with the help of laboratory animals, that thanks to these inhibitors, the cells of the immune system can recognize the cancer cells that normally "slip out" of the immune system and form cancer tumours.

According to the National Research Centre "Dimokritos", these research results "for the first time clearly show that the pharmacological inhibition of enzymes that destroy the antigenic peptides may be a promising new solution to cancer immunotherapy. This is paving the way for future research to optimize and evaluate the possible clinical applications of this category of inhibitors."