Researchers from VIB, Leuven University and University Hospital Leuven studied thousands of healthy and cancerous lung cells to create the first comprehensive atlas of lung tumour cells.

Their results reveal that tumours are much more complex than previously appreciated, distinguishing 52 different types of cells.

This new information can be used to identify new research lines for treatment.

The results of the study were published in Nature Medicine.

While scientists have made enormous headway in the fight against cancer, scientific understanding of tumours at the level of their most fundamental unit - the cell - has been relatively limited.

With the advent of new technologies such as single-cell sequencing, big data analytics and advanced bioinformatics pipelines, it is now possible to examine individual cells within their microenvironments at high resolution, for rich insights into their phenotypes.

Tumours are very complex ecosystems of cells that interact with their native environments.

Studying them in detail requires technologies that have only recently become accessible.

The researchers used single-cell RNAseq technology to study almost 100,000 individual cells, focusing on both cancerous cells and non-cancerous cells in tumours such as blood vessels, immune cells and fibrous cells to create the very first 'atlas' of cell phenotypes found in lung tumours.

Prof. Diether Lambrechts (VIB-KU Leuven): "We were surprised to discover that there are actually many more different cell types in lung tumours than expected. We identified 52 different types of cells, versus the dozen cells already known to be present. This indicates that tumours are even more complex than we had realised."

Many of the cells in tumours have never before been characterised in their native environments.

Because the team analysed both tumour cells and lung cells found outside the tumour and compared the two, they were moreover able to observe how each cell type is altered by the tumour.

Prof. Bernard Thienpont (KU Leuven): "The comprehensive tumor cell atlas that we developed provides a benchmark for cell types that, up to this point, have typically only been studied in-depth in vitro or in animal models. For the first time, we are capable of seeing to what extent these models reflect the actual situation in patients.

"With these results, we've also opened up numerous avenues for future research. Do our findings hold true in other tumour types? How are these cells affected by therapy, and how do they develop resistance? What are the physical locations of these cell types in tumours and can we put together a cellular building plan for tumours? How do tumours produce and support this remarkable complexity, and can we develop therapies that take advantage of tumour-specific vulnerabilities? All of these questions are now ripe for exploration."

Dr. Els Wauters (Leuven University Hospitals) adds: "The new information that we've gathered will be used to develop new strategies to fight the formation of blood vessels in tumours and to test new potential targets for immunotherapy. In addition, we also demonstrated that the presence of some types of cells is associated with lower patient survival, further emphasising the clinical importance of our findings.

Source: VIB