It is common knowledge that a working immune system is pivotal to cancer survival. Due to long latency periods, mesotheliomas and other types of cancer often develop in older patients. In a recent Australian study, researchers discovered why immune response in animals deteriorates with age and explained how their new-found understanding may impact on future cancer therapies. Findings were published in the Frontiers in Genetics journal.[i]
3-month-old mice (18-year-old human equivalent) and 24-month-old mice (60 to 70-year-old human equivalent) with mesothelioma were used as test subjects in the Curtin University, Australia, study. Both groups of mice were treated with immunotherapy to induce an anti-tumour response.
From the outset, lead author and PhD student at the School of Pharmacy and Biomedical Sciences, Lilinh Duong, identified:
‘Our immune system plays a crucial role in eliminating these cancerous cells; yet immune function usually deteriorates as we age’.
Interestingly, the laboratory experiments showed that macrophages, a specialist white blood cell that is involved with the detection and destruction of harmful cells,[ii] ‘sabotaged anti-tumour responses in the elderly, meaning that mesothelioma tumours in elderly mice were more aggressive and less responsive to immunotherapy’.
Their scientific breakthrough was demonstrated by weight loss, muscle wasting and loss of appetite, observed in the elderly mice; symptoms which were beyond those reasonably caused by cancer alone.
Can macrophage cells be removed?
Answering this question, co-author of the paper, Dr Connie Jackaman, explained that their conclusions could result in improved cancer treatment specifically benefitting older patients:
‘Our current research is examining why our immune cells change as we age and whether we can target these cells to restore immune function in the elderly. Understanding these changes could help to inform treatments in elderly cancer patients specifically’.
In other mesothelioma-related news, researchers from the University of Arizona have strengthened earlier study findings on the use of surgery in mesothelioma cases, which we discussed in edition 249 of BC Disease News (here).
In 878 mesothelioma cases, the researchers observed that the results of aggressive surgical procedure were just as positive for sarcomatoid and biphasic mesothelioma patients as for epithelioid mesothelioma patients.[iii]
[i] ‘Study Shows Mesothelioma Tumors Grow Faster In Elderly Lab Animals’ (6 November 2018 Mesothelioma.net) <https://mesothelioma.net/mesothelioma-news/study-shows-mesothelioma-tumors-grow-faster-in-elderly-lab-animals/> accessed 8 November 2018.
[ii] ‘Macrophages’ (British Society for Immunology) <https://www.immunology.org/public-information/bitesized-immunology/cells/macrophages> accessed 8 November 2018.
[iii] ‘Second Study Points to Essential Role of Surgery for Patients with All Mesothelioma Subtypes’ (2 November 2018 Mesothelioma.net) <https://mesothelioma.net/mesothelioma-news/second-study-points-to-essential-role-of-surgery-for-patients-with-all-mesothelioma-subtypes/> accessed 8 November 2018.