Skip to content

Researchers uncover more about the elusive pericyte-tumour interaction.

Tumours are known to evade the immune system by a variety of mechanisms, one of which is the recruitment of ‘myeloid-derived suppressor cells’ (MDSC). MDSCs suppress the ability of the immune system’s killer T-cells to destroy cancer cells. It is known that the more MDSCs present, the worse the prognosis or therapy response of the patient. Tumours secrete signal molecules such as interleukin-6 (IL-6) that help in recruiting MDSCs, however; the mechanisms behind IL-6 tumour secretion are quite unknown.

Now, a study from researchers at Karolinska Institutet is the first to suggest that cells in the tumour blood vessels contribute to a local environment that protects the cancer cells from these tumour-killing immune cells. The team state that their study can contribute to the development of better immune-based cancer therapies.  The study is published in the Journal of the National Cancer Institute.

Previous studies show that pericytes, which envelope the vascular endothelium throughout the body, are often targeted to promote vascular normalization and restore normal function of blood vessels in cancer treatment. The goals of pericyte-targeted therapy tend to promote proper vascular normalization of the tumour.

Tumour vascular normalization is shown in earlier studies to prevent metastasis, make radiation more effective in killing tumour cells and increase delivery of cancer cell-directed therapies as well as the efficacy of focal therapies such as surgery or radiation.  It has also been shown to increase recognition by the host immune system as in an immunotherapy.  However, much is still unknown pertaining to pericyte origin, function, or interaction with other tumour components. Emerging evidence suggest that pericytes may regulate leukocyte transmigration.

The current study found that tumour pericytes critically manipulate the tumour environment, helping the cancer cells escape immune surveillance.  The lab explain that understanding the interplay between tumour pericytes, malignant cells, and the immune system might help in designing more precise and effective therapeutic approaches.

The results show that the higher the number of pericytes, the more normal the tumour environment looked like. Data findings show that diminished pericyte numbers altered the microenvironment and correlated to higher IL-6 expression from the malignant cells and more MDSCs. The researchers also identified a subset of breast cancer patients who had fewer pericytes and increased MDSCs, correlating to a worse prognosis and more aggressive characteristics of the tumour.

The team surmise that their work suggests that ways to increase the numbers of pericytes could potentially decrease IL-6 expression, which could then improve cytotoxic T-cell activity and result in an antitumour effect.

Source:  Karolinska Institutet

 

Angiogenesis of a cancer (a sarcoma) in a rat. Note the chaotic pattern of blood vessels around the tumor (right) in contrast to their orderly pattern on the left. Photomicrograph courtesy of Dr. Robert D. Acland.
Angiogenesis of a cancer (a sarcoma) in a rat. Note the chaotic pattern of blood vessels around the tumor (right) in contrast to their orderly pattern on the left. Photomicrograph courtesy of Dr. Robert D. Acland.

Healthinnovations View All

Michelle Petersen is the founder of Healthinnovations, having worked in the health and science industry for over 21 years, which includes tenure within the NHS and Oxford University. Healthinnovations is a publication that has reported on, influenced, and researched current and future innovations in health for the past decade.

Michelle has been picked up as an expert writer for Informa publisher’s Clinical Trials community, as well as being listed as a blog source by the world’s leading medical journals, including the acclaimed Nature-Springer journal series.

Healthinnovations is currently indexed by the trusted Altmetric and PlumX metrics systems, respectively, as a blog source for published research globally. Healthinnovations is also featured in the world-renowned BioPortfolio, BioPortfolio.com, the life science, pharmaceutical and healthcare portal.

Most recently the Texas A&M University covered The Top 10 Healthinnovations series on their site with distinguished Professor Stephen Maren calling the inclusion of himself and his team on the list a reflection of “the hard work and dedication of my students and trainees”.

Michelle Petersen’s copy was used in the highly successful marketing campaign for the mega-hit film ‘Jumanji: The Next Level, starring Jack Black, Karen Gilian, Kevin Hart and Dwayne ‘The Rock’ Johnson. Michelle Petersen’s copywriting was part of the film’s coverage by the Republic TV network. Republic TV is the most-watched English language TV channel in India since its inception in 2017.

An avid campaigner in the fight against child sex abuse and trafficking, Michelle is a passionate humanist striving for a better quality of life for all humans by helping to provide traction for new technologies and techniques within healthcare.

Leave a Reply

Translate »