Immunotherapy for breast cancer patients because of a variant common in Asians?

Did you know that if we didn’t have active immune systems, most of us could get cancers? Cancer cells produce invisibility cloaks to hide from our immune system’s “checkpoints”, allowing them to grow and spread. Luckily, scientists have found a way to wake up the immune system to hunt cancer cells, and has already resulted in long-term remission for melanoma, lung, and other cancers.

Most breast cancers are thought to be unlikely to respond to this type of treatment, but research conducted in Asians suggest otherwise. Working together with scientists at the University of Cambridge, we found that 60% of Asians inherit a genetic variant that makes our breast cancers more likely to have lots of immune cells and this suggests that Asian breast cancer patients may benefit from immunotherapy.

“Checkpoint immunotherapy has so far shown to be promising to treat an aggressive form of breast cancer, called triple-negative breast cancer, but it is clear that not all patients benefit from this type of treatment. Through research at Cancer Research Malaysia, we now know that more than half of Asian women inherit a genetic variant, and in these women breast cancers tend to have a lot of damaged DNA, which suggests that their tumours are more likely to respond to checkpoint immunotherapy. Importantly, this genetic variant is four times more common in Asians compared to Caucasians. In Jun 2020, we launched this unique clinical trial to test whether checkpoint immunotherapy can indeed improve the treatment response for breast cancer patients with this genetic variant, and this could lead to a new treatment regimen for Asian breast cancer patients,” explained Professor Datin Paduka Dr Teo Soo Hwang, OBE, Chief Scientific Officer at Cancer Research Malaysia, who led the genomics study.

“In this era of precision medicine, we now know that understanding which patients will respond to which treatments is critical in our effort to save lives. Previously, much of the knowledge about precision medicine has been built based on research on Caucasian patients, and it is a milestone for us in Malaysia to be launching this first clinical trial that is based on genetic markers which are common in Asian women, made possible by research conducted here in Malaysia,” said Associate Professor Dr Ho Gwo Fuang, Consultant Oncologist and Principal Investigator of the AUROR Trial at UMMC.

Asians are heavily underrepresented in cancer research. This means that there are still gaps in our understanding of cancers affecting Asians; in knowing how Asian genes affect our risk of developing the disease as well as our response to treatments. Put simply, we test treatments based mainly on Caucasian profiles, and hope they will work equally well in Asians. While this works in most cases, Cancer Research Malaysia believes we can do better.

“This is the first clinical trial launched in Asia to test a feature of breast cancers using a genetic marker that is more common in Asians. We are working on more such clinical trials and hope that more Malaysians will support the work we do; as a non-profit, we depend on contributions to fund our lifesaving research,” added Dr Pan Jia Wern, co-lead of the genomics programme at Cancer Research Malaysia.

CRMY, along with research institutes in Korea and China, has propelled genomics research in the Asian population by 15-fold – in 2015, only 2% of breast cancer genomes available to researchers were from Asian women, this has increased to about 30% in 2020, with the CRMY cohort making up more than half of the new Asian breast cancer genomes. This will lead to a better understanding of genetic markers in Asian breast cancers, and create more opportunities to discover tailored, personalised, or precise treatment options for Asian women. For example, the success of the AUROR clinical trial could result in a better standard of care for Asian breast cancer patients and bring us a step closer to personalised medicine for Asians.

Imagine that. In the future, we could have treatments which are better for us because we are uniquely Asians. If we don’t do this type of research for us, who will? To support the work that we do here, you can donate to cancerresearch.my/donate