Gut microbes linked to immunotherapy response in melanoma patients
Patients with malignant melanoma — whose disease has spread — are more likely to respond to immunotherapy treatment if they had greater diversity in their gut bacteria, according to new research* presented at the National Cancer Research Institute's (NCRI) Cancer Conference in Liverpool.
Scientists at the University of Texas MD Anderson Cancer Centre studied over 200 mouth and over 100 gut microbiome samples from people who had advanced melanoma.
They discovered that people whose cancer responded to immunotherapy treatment had more diversity in the types of bacteria found in their gut. They also found significant differences in the type of bacteria found in the gut of people whose cancer responded versus those who didn't. There was no difference in the type of mouth bacteria between patients.
Early studies in mice have shown that changing the type of bacteria that live in the gut can improve the response to immunotherapy, but this is one of the first studies to look at the link in patients.
Immunotherapy, which harness the body's immune system to target cancer cells, are an exciting avenue of cancer treatment. However, not all patients respond to these treatments, and researchers are trying to understand why.
This research suggests that adapting people's gut bacteria, such as giving antibiotics, probiotics, or a faecal transplant before immunotherapy, could increase the benefits already achieved with new immunotherapy drugs now being used to treat several different types of cancer. However, this needs to be tested clinical trials.
Melanoma is the fifth most common cancer in the UK with about 14,600 people being diagnosed each year. And each year about 2,300 die from the disease.
Dr Jennifer Wargo, lead researcher at the University of Texas, said: "Our research shows a really interesting link that may mean the immune system is aided by gut bacteria when responding to these drugs. Not all patients respond to immunotherapy drugs and it's hard to know who will benefit from the treatment prior to it being given.
"The gut microbiome can be changed through a number of different strategies, so there is real potential here to modify the gut microbiome to boost an immunotherapy response."
Dr Pippa Corrie, Chair of the NCRI's Skin Cancer Clinical Studies Group, said: "There is growing evidence that gut bacteria play a vital role in warding off disease, absorbing nutrients from the food we eat, and maintaining normal function of our immune systems.
"Gut microbes have been shown to influence the role of conventional chemotherapy, so it's probably not surprising that they impact on response to new immunotherapies being used in the clinic. Manipulating the gut flora may be a new strategy to enhance activity of immunotherapy drugs, as well as to manage problematic toxicity in the future."
This research was funded by the Melanoma Research Alliance and by the Melanoma Moon Shot Program at MD Anderson Cancer Center.
For media enquiries contact Stephanie McClellan in the NCRI press office on 020 3469 5314 or, out of hours, on 07050-264-059.
Notes to editor:
* Plenary session: Understanding responses to cancer therapy: The tissue is the issue but the scoop is in the poop – Jennifer Wargo, The University of Texas MD Anderson Cancer Center, USA
**Statistics based on the number of new cases and deaths from melanoma skin cancer (ICD10 C43) in the UK between 2012-2014.
Melanoma skin cancer incidence rates have increased by 119% (from 11 cases per 100,000 people between 1993-1995 to 25 cases per 100,000 people between 2012-2014).
About the NCRI
The National Cancer Research Institute (NCRI) is a UK-wide partnership of cancer research funders, established in 2001. Its 19 member organisations work together to accelerate progress in cancer-related research through collaboration, to improve health and quality of life.
NCRI works to coordinate research related to cancer, to improve the quality and relevance of the research and to accelerate translation of the research into clinical practice for the benefit of patients.
NCRI Partners are: Biotechnology and Biological Sciences Research Council; Bloodwise; Breast Cancer Now; Cancer Research UK; Children with Cancer UK, Department of Health; Economic and Social Research Council (ESRC); Macmillan Cancer Support; Marie Curie; Medical Research Council (MRC); Northern Ireland Health and Social Care Public Health Agency (Research & Development Department); Pancreatic Cancer Research Fund; Prostate Cancer UK; Roy Castle Lung Cancer Foundation; Scottish Government Health Directorates (Chief Scientist Office); Tenovus Cancer Care; The Wellcome Trust; Welsh Assembly Government (Health and Care Research Wales); and Worldwide Cancer Research.
For more information visit http://www.ncri.org.uk
About the NCRI Cancer Conference
The NCRI Cancer Conference is the UK's largest cancer research forum for showcasing the latest advances in British and international oncological research spanning basic and translational studies to clinical trials and patient involvement.
- The conference offers unique opportunities to network and share knowledge by bringing together world-leading experts from all cancer research disciplines.
- The NCRI Cancer Conference is taking place from 6-9 November 2016 at the BT Convention Centre in Liverpool.
- For more information visit conference.ncri.org.uk; Twitter @NCRI_Partners; #NCRI2016