Finding new ways to treat metastatic (advanced) breast cancer

Breast cancer remains one of the most common cancers affecting Australians. While many cases are treatable, metastatic breast cancer (mBC) – when the cancer has spread to other parts of the body – remains a major challenge.

Each year, around 3,000 Australians die of mBC. That’s why Professor Alexander Swarbrick and his team including Tony Wang and Kate Harvey at the Garvan Institute of Medical Research have been working tirelessly to better understand the disease and find new ways to treat it.

Funded by Cancer Council NSW, the team has made significant progress in studying the biology of mBC. Their findings could pave the way for better treatment strategies and improved outcomes for people with advanced breast cancer.

A deeper look at metastatic breast cancer

Metastatic breast cancer is difficult to treat because it spreads beyond the breast to vital organs like the lungs, liver, and bones. Understanding how the cancer adapts and survives in these new environments is critical to developing effective therapies.

To tackle this challenge, researchers have used cutting-edge technologies to study mBC at the cellular level.

By mapping the genetic and molecular landscape of metastatic tumours, they are revealing new insights into how cancer cells interact with their surroundings and evade treatments.

A world-first dataset for breast cancer research

One of the biggest breakthroughs from this research is the creation of the first-ever single-cell and spatial transcriptomic dataset for mBC.

Using a new technology called snPATHO-seq, the team successfully analysed tumour samples from metastatic breast cancer patients.

Now the researchers can study what role individual cells have within a tumour, even in archived tissue samples that were previously difficult to analyse.

With this data, scientists can now identify key changes in tumour cells and surrounding immune cells, helping to find new treatment targets.

How this research is changing the game

1. Discovering cancer’s weaknesses

By analysing tumour samples from different organs, researchers found that metastatic cancer cells behave differently depending on where they spread.

For example, they identified:

• Unique gene activity in liver-resident macrophages (cells of the immune system), which could be targeted for future treatments.
• Changes in tumour-associated macrophages that may explain how cancer evades the immune system response.

These findings provide a roadmap for developing more personalised treatments based on the specific characteristics of a patient’s cancer.

2. Advancing technology to study cancer

To better understand how cancer cells interact within tumours, the team developed new ways to map “cellular neighbourhoods”.

This means they can now visually track how different cells are positioned in a tumour and how they communicate. This helps identifcation of critical points where treatments can disrupt cancer growth.

3. Overcoming research challenges

Due to COVID-19, the team faced difficulties collecting fresh tumour samples from patients. Instead of pausing their research, they adapted by using new technologies that work on stored tissue samples.

This shift not only allowed them to continue their work but also created opportunities for studying archived cancer samples from patients who have already undergone treatment.

This means future research could reveal how past treatments influenced tumour evolution.[MW1] 

What’s next?

With these exciting discoveries, the researchers are now looking forward to their next steps:

• Refining their analysis to pinpoint exactly how metastatic breast cancer adapts to treatments.
• Developing new treatment strategies based on their findings, with the hope of reversing drug resistance.
• Making their dataset publicly available to help other researchers around the world continue advancing mBC research.

This research has the potential to change how we understand and treat mBC – offering hope to patients who currently face limited treatment options.

These breakthroughs wouldn’t be possible without research funding, and that’s where the support of Cancer Council NSW donors and fundraisers makes a real difference.

By funding world-class research, we’re helping scientists find new ways to detect, treat, and ultimately to save lives.

Every discovery brings us closer to the next research milestone.

To support more life-saving cancer research and programs, consider making a donation today.