These are exciting times for scientific research in our fight against cancer. An effective cancer therapy directly targets tumour cells without being toxic to health tissue. The latter has been a long-standing limitation of conventional therapies, such as chemotherapy and radiotherapy.

The forefront in our battle against cancer is directed at exploiting the patient’s own immune system to recognise and specifically destroy the tumour cells without affecting the healthy ones. In all types of cancers, a very small number of cells transform, start dividing uncontrollably and take over healthy cells before spreading to other areas of the body. The immune system has evolved to discriminate between tumour and healthy cells. Any malignant cells detected by the immune system at the early stages of transformation are swiftly eliminated from the body. Unfortunately, although the immune system can distinguish minute differences between healthy and tumour cells, the latter develop various ‘cloaking’ mechanisms that result in evasion of the initial immune response.

Current scientific efforts are directed at developing strategies that reactivate and bolster an adequate immune response against cancer cells. The most promising among these strategies include adoptive cell transfer and immune checkpoint blockade. In adoptive cell transfer, specific white blood cells called lymphocytes are isolated from the patient and expanded in the laboratory. These lymphocytes are then genetically engineered to make them more effective against tumour cells, prior to being reinfused back to the patient. This form of therapy has resulted in effective regression of several types of tumours such as lymphomas, melanomas and some types of sarcomas. The main drawback of this approach is the inherent cost to isolate and engineer cells on a patient-by-patient basis.

While the immune system elicits a response against cancers, this is not always efficient since tumour cells become tolerant by switching off immune cells. Scientists have designed specific molecules called monoclonal antibodies that block cancer cells from hitting the switch off button. These therapies are being used to treat melanomas and Hodgkin lymphoma. A huge effort by the international scientific community is currently under way to identify novel switches that can be blocked, some of which are in clinical trials. Clinically-approved checkpoint inhibitors are also being used in combination with conventional chemotherapy to target a wider variety of cancers.

The focus of my research is to understand how white blood cells communicate with one another through the formation of a specialised structure called the immunological synapse. Our recent discovery, published in the scientific journal Nature, explains how immune cells establish a more robust response by employing molecules, such as dopamine, that are typically involved in the communication by nerve cells.

David Saliba is a scientific researcher at the Centre for Molecular Medicine and Biobanking at the University of Malta and also holds an honorary research position at the Kennedy institute of Rheumatology at the University of Oxford.

Sound bites

• The Neuronal and Immune Synapse: Sir Charles Scott Sherrington received the Nobel Prize in Physiology and Medicine in 1932 for elucidating how neurons communicate through contact points which he termed synapses. Similar to the neuronal synapse, Prof. Michael Dustin coined the definition “Immune Synapse” to describe a specialised zone of communication between lymphocytes (white blood cells of the immune system). The immune synapse is also used by special killer white cells (called cytotoxic lymphocytes) to detect and kill tumour cells. It is interesting to point out that the human immunodeficiency virus (HIV) hijacks the immune synapse to flow from one white blood cell to an uninfected one. Scientists from both the fields of immunology and neuroscience are examining the molecular structures of these cellular contacts and using the knowledge to develop new therapies for neurodegenerative diseases as well as cancer.

https://www.kennedy.ox.ac.uk/news/dopamine-rewards-immune-cells-through-immunological-synapse

• CancerSEEK – a new Cancer blood test: Detecting cancer early is crucial to prevent it from growing and spreading to other areas of the body. The ultimate goal would be to have a quick universal blood test that detects all forms of cancer. Two weeks ago researchers from the Johns Hopkins University have published research, reported in the scientific journal Science, which is a step in this direction. Tumour cells release altered genetic material (DNA) and defective proteins into the bloodstream. This study, led by Dr Cristian Tomasetti, was able to detect 70 per cent of ovary, liver, stomach, pancreas and oesophagus cancers from 1,005 patients. Five of the eight cancers investigated have no screening methods for early detection. Pancreatic cancer has a high mortality so being able to detect this form of cancer early can allow for early surgical removal of the affected tissue. Such tests can also be used for patients that have already been diagnosed with cancer but are in partial remission. These tests will be much quicker at detecting relapse of the cancer thereby allowing better management of the disease.

https://www.sciencedaily.com/releases/2018/01/180118141803.htm

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Did you know?

• World Cancer Day takes place today, where people unite in the fight against cancer. #WeCanICan take action to help prevent and fight #cancer http://bit.ly/WCD2018

• Autoimmune diseases occur when the immune system destroys its own healthy tissues instead of protecting them.

• Lack of sleep may make you more vulnerable to catching a cold or fight off infection.

• Psoriasis is a common skin condition that speeds up the life cycle of skin cells and rapidly causes cells to build up rapidly on the surface of the skin.

• As a result of the body’s misguided attack on your system due to an allergic reaction, symptoms may be as insignificant as a runny nose to breaking out in hives to fainting.

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