New research on inflammation could lead to better treatments to improve outcomes for people with advanced or previously untreatable cancers.
Introducing bacteria to a tumour’s microenvironment creates a state of acute inflammation that triggers the immune system’s primary responder cells to attack rather than protect a tumour, according to researchers from UNSW Sydney and the Garvan Institute of Medical Research.
At the earliest signs of bacterial infection, the first cells on the scene are white blood cells called neutrophils, which play an important role in the defense against infection.
While they generally protect against disease, they are notorious for promoting tumour growth. High levels of them in the blood are typically associated with poorer outcomes in cancer, in part because they produce molecules that shield the tumour by suppressing the other elements of the immune system.
The team of scientists discovered that injecting inactivated samples of the Staphylococcus aureus microbe into the tumour microenvironment – the area surrounding the tumour – flips the protective function of neutrophils.
The research, published in the journal Cancer Research, was led by Associate Professor Tatyana Chtanova at UNSW’s School of Biotechnology and Biomolecular Sciences and Head of the Innate and Tumour Immunology Lab at Garvan. A/Prof Chtanova says that these findings have helped progress our understanding of acute inflammation to advance microbial therapy for cancer.
“In our study we sought to develop new immunotherapies that use different modes of action that could complement and enhance existing immunotherapies,” says A/Prof Chtanova.
“We show how acute inflammation can be harnessed to achieve ongoing anti-tumour function in immune cells. We also show how microbial therapy can be successfully combined with an existing type of therapy, known as checkpoint inhibitor therapy, to amplify anti-cancer capabilities.”
Exploring new ways of triggering the immune system to fight cancer
Working on a range of animal cancer models, including Lewis lung carcinoma, triple-negative breast cancer, melanoma and pancreatic cancer, the presence of bacteria stimulated the neutrophils to destroy the tumours.
“Using the immune system to fight cancer has been one of the biggest breakthroughs in cancer therapy in the last two decades, but currently immunotherapy for improving T cell function [another important type of white blood cell] doesn’t work for all types of cancer,” says A/Prof Chtanova.
“We decided to use a different type of immunotherapy that targets neutrophils, to understand how generating acute inflammation in the immunosuppressive tumour microenvironment affects outcomes.”
The team studied the tumours in real time using a unique imaging method known as intravital imaging.
“Since attacking bacteria is the reason for neutrophils’ existence, we had a good inkling that introducing bacteria would bring neutrophils to the site and activate them. We discovered that it’s very effective in getting them to kill the tumours, chewing up their matrix,” she says.
The study also found that on exposure to bacteria, neutrophils begin to secrete molecules that will attract fighter T cells as reinforcement.
“We’ve shown that microbial therapy is an effective booster for checkpoint inhibitor therapy. We hope this synergistic effect will ultimately lead to better treatments to improve outcomes for patients with advanced or previously untreatable cancers,” says first author of the study, Dr Andrew Yam, clinical medical oncologist at The Kinghorn Cancer Centre and PhD student at Garvan.
This study focused on primary tumours, the first tumour in the body. “So far we have shown that our microbial therapy can inhibit growth of primary tumours and can also protect against tumour recurrence, which is a major clinical challenge,” says A/Prof Chtanova. “This suggests that our microbial therapy is achieving not just short-term and localised, but long-lasting and systemic anti-tumour immunity.
“Our next step is to extend these findings to develop a pathway to treat cancers that have metastasized to different locations.”

News
DREAM complex could hold key to fighting cancer and living longer
DNA may be the stuff of life, but if it isn't repaired in our bodies on a regular basis, it can lead to diseases that can cause some pretty unpleasant types of death. DNA [...]
A Promising New Pathway in the Battle Against Aggressive Prostate Cancer
Neuronal Molecule Makes Prostate Cancer More Aggressive Researchers discover a potential therapeutic avenue against an aggressive form of prostate cancer. Prostate cancer is the second most common cancer and the second leading cause of [...]
Nasal Vaccines: Stopping the COVID-19 Virus Before It Reaches the Lungs
The Pfizer-BioNTech and Moderna mRNA vaccines have played a large role in preventing deaths and severe infections from COVID-19. But researchers are still in the process of developing alternative approaches to vaccines to improve [...]
NASA Tracking a Huge, Growing Anomaly in Earth’s Magnetic Field – with video
NASA is actively monitoring a strange anomaly in Earth's magnetic field: a giant region of lower magnetic intensity in the skies above the planet, stretching out between South America and southwest Africa. This vast, developing [...]
New, Better Models Show How Infectious Diseases Like COVID-19 Spread
Infectious diseases such as COVID-19 can spread rapidly across the globe. Models that can predict how such diseases spread will strengthen national surveillance systems and improve public health decision-making. The COVID-19 pandemic has emphasized the [...]
Human Antibodies Discovered That Can Block Multiple Coronaviruses Including COVID-19
Results from a Scripps Research and UNC team pave the way for a vaccine and therapeutic antibodies that could be stockpiled to fight future coronavirus pandemics. A team of scientists from Scripps Research and [...]
Nanotechnology could be used to treat lymphedema
The human body is made up of thousands of tiny lymphatic vessels that ferry white blood cells and proteins around the body, like a superhighway of the immune system. It's remarkably efficient, but if [...]
DNA Nanotechnology Tools – From Design to Applications
Suite of DNA nanotechnology devices engineered to overcome specific bottlenecks in the development of new therapies, diagnostics, and understanding of molecular structures. DNA nanostructures with their potential for cell and tissue permeability, biocompatibility, and [...]
Regenerating bone with deer antler stem cells
Scientists from a collection of Chinese research institutions collaborated on a study of organ regeneration in mammals, finding deer antler blastema progenitor cells are a possible source of conserved regeneration cells in higher vertebrates. [...]
AI Takes On Cancer: Analysis of Mutations Could Lead to Improved Therapy
Cancer is a complex and diverse disease, and its range of associated mutations is vast. The combination of these genomic changes in an individual is referred to as their “mutational landscape.” These landscapes vary [...]
Exposing tumours to bacteria converts immune cells to cancer killers
New research on inflammation could lead to better treatments to improve outcomes for people with advanced or previously untreatable cancers. Introducing bacteria to a tumour’s microenvironment creates a state of acute inflammation that triggers [...]
Smart nanotechnology for more accurate delivery of insulin
More efficient and longer lasting glucose-responsive insulin that eliminates the need for people with type 1 diabetes to measure their glucose levels could be a step closer thanks to a Monash University-led project. Published [...]
Efficiently Harvesting Rare Earth Elements From Wastewater Using Exotic Bacteria
The novel strains of cyanobacteria exhibit a fast and efficient “biosorption” of rare earth elements, making recycling possible. Rare earth elements (REEs) are a set of 17 metallic elements that possess similar chemical properties. [...]
Resisting Treatment: Cancer Cells Shrink or Super-Size To Survive
A new approach to image analysis has uncovered how cancer cells manipulate their size as a means of resisting treatment. Researchers have discovered that cancer cells are capable of either shrinking or super-size themselves [...]
New Research Explains Why Children Avoid Severe COVID-19 Symptoms
According to new research, children exhibit a robust initial immune response to the coronavirus, however, they are unable to transfer this response to long-lasting memory T cells like adults do. Researchers led by scientists [...]
Scientists Unravel Protein Map of Mitochondria
A new study sheds light on the organization of proteins within mitochondria. Mitochondria, the “powerhouses” of cells, play a crucial role in the energy production of organisms and are involved in various metabolic and [...]