Tag: collagen

Collagen’s Role in Breast Cancer Includes Triggering Metastasis

Breast cancer cells
Breast cancer cells. Image source: National Cancer Institute on Unsplash

Type XII collagen plays a key role in regulating the organisation of the tumour matrix, according to research published in the journal Nature Communications. The study investigators also discovered that high levels of collagen XII can trigger metastasis.

Cancer cells continually interact with the tumour microenvironment one component of which is the extracellular matrix. Collagen is an important part of this tumour microenvironment, but just how it influences tumours has not been understood.

“There’s still a lot we don’t know about the role of the extracellular matrix in cancer metastasis. Our study shows that collagen XII plays an important role in breast cancer progression and metastasis,” said Associate Professor Thomas Cox, senior author of the study.

“Imagine cancer cells as seeds, and the tumour microenvironment as the soil. By studying the soil – the extracellular matrix – we can begin to understand what makes some tumours more aggressive than others, and by extension, begin to develop new ways to treat cancer,” he explained.

The research also suggests that measuring the level of collagen XII in a patient’s tumour biopsy could potentially be used as an additional screening tool to identify aggressive breast cancers with higher rates of metastasis, such as in the triple-negative type of breast cancer. Furthermore, collagen XII might be a possible target for future treatments.

The extracellular matrix is a 3D meshwork of around 300–400 core molecules, including several collagen proteins. This matrix provides structural and functional support to cells and tissues in all parts of the body.

In this study, the researchers catalogued how the tumour matrix changes over time and have generated a comprehensive database of these changes, which has been made freely available to researchers.

The team focused on collagen XII, one of 28 types of collagen in the body. Collagen XII plays an important role in organising other collagens and can have profound effects on the 3D structure of the extracellular matrix.

The researchers studied tumours in mouse models from the earliest pre-clinical stages of cancer, right through to late-stage tumours. They found that as the tumours developed, many matrix molecules changed, and importantly the level of collagen XII was also increased.

“Collagen XII seems to be altering the properties of the tumour and makes it more aggressive,” said first author Michael Papanicolaou. “It changes how collagens are organised to support cancer cells escaping from the tumour and moving to other sites like the lungs.”

The team then genetically manipulated collagen XII production, looking at the effects of metastasis to other organs. They found that as levels of collagen XII increased, so did metastasis. These findings were then confirmed in human tumour biopsies, which showed that high levels of collagen XII are associated with higher metastasis and poorer overall survival rates.

Further research will focus on studying more human samples, and investigating possible therapeutic pathways.

Source: Garvan Institute of Medical Research

Why Cancer Cells Linger to Create Metastatic Cancer

Colon cancer cells. Source: National Cancer Institute on Unsplash

A major mystery in cancer research has been solved: How cancer cells remain dormant for years after leaving a tumour before awakening to create metastatic cancer.

According to findings by Mount Sinai researchers which were reported in Nature Cancer, the cells remain quiet by secreting a type of collagen, called type III collagen, in the environment around themselves, and only turn malignant once the level of collagen tapers off. The researchers found that by enriching the environment around the cells with this collagen, they could force the cells to remain in a dormant state and prevent tumour recurrence.

“Our findings have potential clinical implications and may lead to a novel biomarker to predict tumour recurrences, as well as a therapeutic intervention to reduce local and distant relapses,” said senior author Jose Javier Bravo-Cordero, PhD, Associate Professor of Medicine (Hematology and Medical Oncology) at The Tisch Cancer Institute at Mount Sinai. “This intervention aimed at preventing the awakening of dormant cells has been suggested as a therapeutic strategy to prevent metastatic outgrowth. As the biology of tumour dormancy gets uncovered and new specific drugs are developed, a combination of dormancy-inducing treatments with therapies that specifically target dormant cells will ultimately prevent local recurrence and metastasis and pave the way to cancer remission.”

Most cancer deaths result from metastases, which can occur several years after removal of a tumour. Previous work looked at how dispersed tumour cells awaken from dormancy; this new work showed how the cells remain dormant.

The study used high-resolution imaging techniques, including intravital two-photon microscopy, a technology that allows the visualisation of dormant cells in their environment in real time in a living animal. This technology allowed the researchers to track dormant tumour cells in mouse models using cancer cell lines. By using this technology, the researchers were able to visualise the changes in the architecture of the extracellular matrix as tumour cells became dormant and how it changed when these cells awoke.

The researchers demonstrated that an abundance of the collagen could potentially be used as a predictor of tumour recurrence and metastasis. In the mouse models, when type III collagen was increased around cancer cells that had left a tumour, cancer progression was interrupted and the disseminated cells were forced into a dormant state. Similar to wound treatment, in which collagen scaffolds have been proposed to treat complex skin wounds, this study suggests that by enriching the tumour microenvironment in type III collagen, metastasis may be prevented by sending tumour cells into a dormant state.

Source: The Mount Sinai Hospital / Mount Sinai School of Medicine