Studying the link between oral health and cancer

The oral microbiome not only causes dental diseases, it also impacts on diseases elsewhere in the body. This is the focus of Margaret Sällberg Chen’s research, especially in relation to cancer.

Margaret Sällberg Chen in the lab.
Margaret Sällberg Chen is a professor of clinical oral immunology. Photo: Stefan Zimmerman.

What are you researching?

“I’m a dentist and am investigating how our oral microbiome affects the rest of the body. It’s turned out over the past few decades that there’s a clear link between oral health and numerous common diseases, such as cancer, cardiovascular disease and Alzheimer’s. Since my studies at KI, general attitudes have taken a U-turn – scientists that suspected oral bacteria to be linked to, say, cancer were met back then with a lot of scepticism, but today there’s scientific evidence for it and a great deal of interest amongst doctors and dentists.”

What does your research involve?

“We’re trying to describe both sides of this interaction – the oral microbiome and the immune system that functions as gatekeeper to the human body. This doesn’t only involve white blood cells patrolling in our body like policemen. Our saliva, which contains lots of immune components, is crucial too. My particular focus is on the link between oral health and cancer. The chemical environment in a tumour has ample resemblance to the conditions found in parts of the mouth, such as the periodontal pockets: it’s deprived of oxygen and inflamed.

Oral bacteria have been found in tumours, so it’s possible they can migrate there. Our hypothesis is that the metabolic activity of some bacteria can drive tumour growth. They may modulate cancer immunity and even cause potentially carcinogenic mutations through the genotoxic substances they secrete.”

What are the clinical implications of your findings?

“By understanding the oral health and cancer link, we hope to improve cancer diagnostics and gain better prognostics markers. Saliva is also a promising non-invasive specimen, that we think can help detect cancer early and help patients find effective treatment.”

Margaret Sällberg Chen

Professor of Clinical Oral Immunology at the Department of Dental Medicine

Margaret Sällberg Chen was born in 1967 in Taipei, Taiwan. She earned her degree in dental surgery at KI in 1992, becoming a licensed dentist the following year. She received her PhD in 1998 and went on to do postdoctoral research at the Scripps Research Institute, San Diego, USA. Between 1999 and 2007, she researched at the Swedish Institute for Infectious Disease Control (now the Public Health Agency of Sweden).

She leads a research group at KI comprising five doctoral students and two postdocs. Sällberg Chen was appointed docent in 2004 and in 2010 director of doctoral studies at the Department of Dental Medicine. She has been a visiting professor at Shanghai Tongji University, China, since 2018.

Margaret Sällberg Chen was appointed Professor of Clinical Oral Immunology at Karolinska Institutet on 1 November 2020.

Text: Anders Nilsson
First published in the booklet From Cell to Society 2021.

Watch a video with Margaret Sällberg Chen