Understanding pre-malignant squamous cell carcinoma cell biology, enabling targeted early clinical intervention

Background

Of 40,000 lung cancers diagnosed in England and Wales annually, 43% are squamous cell carcinomas (SqCCs).

Pre-invasive SqCCs arise within the airways. We need to understand more about the cell processes that convert a healthy airway (or epithelial) cell into a pre-cancerous epithelial cell (groups of abnormal cells are known as pre-invasive lesions) and eventually into cancer.

They are defined by step-changes in the shape and structure of the epithelium (the thin tissue forming the outer layer of the airway). These changes can be mild, moderate or severe, all the way through to carcinoma-in-situ (CIS). These CIS lesions can progress to become invasive SqCCs (cancers) but they can also regress, so that the epithelium returns to normal.

The UCL (University College London) research team, led by Dr Robert Hynds, monitored a cohort of patients with pre-invasive endobronchial (airway) lesions over a lengthy period of time, studying the characteristics of progressive lesions. This project aimed, for the first time, to expand cells from CIS patient biopsies establishing a vital new tool in the investigation and testing of preventative therapies.

What is the problem to be addressed?

We need to detect cancer at earlier stages in its progression.

For this to be possible, we need to understand more about the cell processes that convert a healthy airway (or epithelial) cell into a pre-cancerous epithelial cell (groups of abnormal cells are known as pre-invasive lesions) and eventually into cancer.

By understanding this progression, we will be better placed to develop techniques to identify dangerous pre-cancerous lesions early, predict the progression of lesions to cancer and develop new therapies that stop cancer progression in its tracks before established disease can develop.

Dr Robert Hynds

Findings and Outcomes

The project ran from April 2017 to December 2020. Its progress was hampered in the final months by the impact of the COVID-19 pandemic.

This study investigated methods to expand healthy airway cells from smokers, cells from pre-cancerous lesions in the airway and cells from early-stage non-small cell lung cancers in the laboratory. These approaches allow us to study how the airways are normally repaired and what goes wrong during early carcinogenesis.

Through studying cells grown in the lab, including cultures that were derived from individual airway cells, we mapped the changes in the airway during normal ageing and during tobacco smoking (Yoshida et al, Nature, 2020).

To address the challenge of culturing cells from tumours (Hynds et al, IJC, 2018), we have further been able to generate a large bank of early non-small cell lung cancer patient-derived xenograft and organoid models which are now being characterised through follow-on funding from the Wellcome Trust and Cancer Research UK.

Key achievements of the project:

• We established a bioresource of cells from smokers and patients with either pre-invasive or early-stage lung cancers.
• We showed the impact of ageing and tobacco smoking on the genomes of airway cells for the first time using innovative cell culture methods.
• We have developed methods to grow airway cells in cell culture that will be widely applicable in other research.
• We investigated using our methods for ‘normal’ airway cells in early-stage non-small cell lung cancer.

Note: While these results revealed a great deal about changes in ‘normal’ airway cells in smokers and we have established laboratory models of early-stage non-small cell lung cancer, we remain unable to grow cells from pre-cancerous lesions, either in cell culture or in animal models. This is a challenge for the field internationally and will require more work in the future.

The potential/actual benefits of this project to a person with lung cancer:

• In the medium term, our ability to grow cells in the laboratory from both normal and early-stage non-small cell lung cancers might enable a more personalised approach to lung cancer therapy, where selection of the appropriate therapy is informed by testing them on the patient’s own tissue samples.
• In the longer term, our findings about normal airway cell biology will allow the development of therapies that target lung cancers earlier and promote lung repair.

This project produced data and reports published in several journals, contributing considerably to the literature surrounding this particular aspect of lung cancer research.

Publications:

How presented (oral, poster or journal publication)	Title	Year	Authors	Journal publication name / conference venue	Status (in submission, in press or published)
Journal (Editorial)	The secret lives of cancer cell lines.	2018	Hynds, R.E., Vladimirou, E. and Janes, S.M.	Disease Models and Mechanisms	Published
Journal (Article)	Cross-talk between human airway epithelial cells and 3T3-J2 feeder cells involves partial activation of human MET by murine HGF.	2018	Hynds, R.E., Gowers, K.H., Nigro, E., Butler, C.R., Bonfanti, P., Giangreco, A., Prêle, C.M. and Janes, S.M.	PLOS ONE	Published
Journal (Article)	Optimized isolation and expansion of human airway epithelial basal cells from endobronchial biopsy samples.	2018	Gowers, K.H., Hynds, R.E., Thakrar, R.M., Carroll, B., Birchall, M.A. and Janes, S.M	Journal of Tissue Engineering and Regenerative Medicine	Published
Journal (Article)	Expansion of airway basal epithelial cells from primary human non-small cell lung cancer tumors.	2018	Hynds, R.E., Ben Aissa, A., Gowers, K.H.C., Watkins, T.B.K., Bosshard-Carter, L., Rowan, A.J., Veeriah, S., Wilson, G.A., Quezada, S.A., Swanton, C., TRACERx Consortium, Janes S.M.	International Journal of Cancer	Published
Journal (Article)	Tobacco exposure and somatic mutations in human bronchial epithelium.	2020	Yoshida, K.*, Gowers, K.H.C.*, Lee-Six, H., Chandrasekharan, D.P., Coorens, T., Maughan, E.F., Beal, K., Menzies, A., Millar, F.R., Anderson, E., Clarke, S.E., Pennycuick, A., Thakrar, R.M., Butler, C.R., Kakiuchi, N., Hirano, T., Hynds, R.E., Stratton, M.R., Martincorena, I., Janes, S.M. and Campbell, P.J.	Nature	Published
Pre-print	Cell-intrinsic differences between human airway epithelial cells from children and adults.	2020	Maughan, E.F., Nigro, E., Pennycuick, A., Gowers, K.H.C., Denais, C., Gómez-López, S., Lazarus, K.A., Butler, C.R., Lee, D.D.H., Orr, J.C., Teixeira, V.H., Hartley, B.E., Hewitt, R.J., Al Yaghchi, C., Sandhu, G.S., Birchall, M.A., O’Callaghan, C., Smith, C.M., De Coppi, P., Hynds, R.E. # and Janes, S.M.#	bioRxiv	Pre-print, submitted to journal
Journal (Review)	Progress towards non-small cell lung cancer models that represent clinical evolutionary trajectories.	2021	Hynds, R.E.#, Frese, K., Pearce, D., Grönroos, E., Dive, C. and Swanton, C.	Open Biology	Published

Other important collaborations have resulted from this project, including work with Prof Peter Campbell of the Sanger Institute, Cambridge, and with Prof Charles Swanton of the Francisd Crick Institute, London. Both collaborations led to further funding awards for subsequent research.

Summing up the value of the funding he received from the Foundation, Dr Hynds said: ‘’This was a significant factor in the award of my subsequent Wellcome Trust fellowship. It has provided funds for two postdoctoral researchers and led to significant follow-on funding.

‘’I am very grateful to the Foundation for their contribution to our work and for their flexibility to extend the funding when our plans changed.’’

Lead researchers: Dr. Robert Hynds | Location: University College London | Type of research: Early detection