The resistance of mesothelioma cancer to all forms of asbestosis treatments has continued to challenge clinical researchers around the world.

Considerable advances have been made in understanding the behaviours of mesothelioma cancer and how the underlying cellular, protein and genetic mechanisms impact upon individual patients. To date, there is still no cure to completely stop the development of malignant tumours, which may take between 15 to 50 years from the initial period of exposure to when asbestosis symptoms start to appear.

Irritation and inflammation

A key area of ongoing research is in trying to better understand exactly how mesothelioma develops from the time when the asbestos fibres embed in the tissue linings of the lungs or stomach.

It’s known that the fibres trigger irritation and inflammation, and proteins present in the cancer tumours play a role in suppressing the body’s immune system from responding and trying to attack the cancer. However, clinicians are still unclear as to exactly how cells are first turned cancerous, which eventually form tumours.

Researchers have recently been able to isolate two small proteins called cytokines, which they believe could be responsible for the increased response, which promotes inflammation. Cytokines are ‘cell signalling’ molecules. which aid cell to cell communication in immune responses. Cells are stimulated by the molecules to move towards sites of inflammation, infection and trauma.

Increased cell death

In a recent laboratory study, clinicians exposed cells from the lung linings of mice to two types of asbestos fibres – blue crocidolite and white chrysotile – for periods between four and 48 hours. The results showed that the asbestos-exposed cells had ‘over produced’ inflammatory cytokines.

It was further found that the rate of programmed cell death and necrosis was at a much higher level. Programmed cell-death is defined as the death of a cell in any form, and necrosis is the death of a cell caused by external factors, such as trauma or infection, which occurs in several different forms.

To verify that cytokines were responsible for the inflammatory response, the researchers neutralised the cytokines with antibodies, which effectively switched off their signalling ability. It was found that neutralisation of the proteins inhibited the death of the healthy mesothelial cells. The researchers concluded that cytokines do “contribute to asbestos-induced injury.”

The results suggest new possibilities in developing more effective “anti-inflammatory” treatments to intervene in combating the development and spread of mesothelioma cancer. A further proposal is to test those who have been exposed to asbestos for the presence of the protein.

Critical factor

Early detection of mesothelioma has always been a critical factor for improved treatment outcomes and extending life expectancy rates. The majority of patients are still being diagnosed at the most advanced stages when the diffuse spread of malignant tumours has reached distant organ tissues and expected survival can often be less than six months.

Mesothelioma mortality in the UK has increased from 2,291 deaths in 2011 to 2,535 in 2012, a rise of more than 10 per cent, according to the latest available figures from the Health and Safety Executive (HSE).