The role of PPFIA1 (Liprin-α1) in pancreatic cancer

About the Project

Pancreatic cancer (PDAC) remains a lethal disease with a 5-year survival rate of ~10%. PDAC progression is associated with profound changes in the extracellular matrix (ECM) that surround and support tumour cells. This project aims to characterise the role of a cell-ECM adhesion-associated protein (Liprin-α1) in PDAC cell biology, using cutting-edge microscopy and mass spectrometry techniques.

A key hallmark of pancreatic ductal adenocarcinoma (PDAC) is the development of a dense tumour stroma, consisting of extracellular matrix (ECM), vascular cells, and immune cells. Collectively, this forms the tumour microenvironment (TME). Our understanding of how PDAC cells interact with the ECM as it changes, and how this affects the cell biology of PDAC cells, remains limited.

This project will build upon pilot data suggesting a role for the cell-ECM adhesion related protein Liprin-α1 (PPFIA1) in regulating PDAC cell motility and proliferation. Liprin-α1 is implicated in breast and head & neck cancer progression, but its role in PDAC remains unexplored.

Liprin-α1 localises adjacent to cell-ECM adhesions (called focal adhesions, FAs) in structures called cortical microtubule stabilising complexes (CMSCs). FAs connect to the actin cytoskeleton and act to sense and respond to changes in ECM (including its biochemical makeup as well as its biophysical properties), whilst CMSCs connect FAs to microtubules. Compared to FAs, which have been well studied for approximately half a century, our knowledge of CMSCs and the proteins therein remains in its infancy.

Project aims:

• To use molecular biology tools (siRNA, shRNA, CRISPR) to knockdown Liprin-α1 in immortalised PDAC cell lines and assess cell motility and proliferation when cells are rescued with Liprin-α1 constructs lacking key domains regulating protein-protein interactions;
• To use proximity biotinylation and mass spectrometry (BioID) to characterise proteins in the neighbourhood of Liprin-α1, with interactors confirmed by pull-down experiments;
• To use cutting-edge microscopy techniques to study the dynamics of Liprin-α1 in PDAC cells (including time-lapse confocal imaging, fluorescence recovery after photobleaching (FRAP), super-resolution imaging) when cultured on different ECM proteins to recapitulate the changing landscape of the ECM in PDAC.

Training and Environment:

The Atherton lab has years of experience in using mass spectrometry for identifying protein-protein interactions (refs), as well as in all microscopy techniques that will be used in this project. These experiments will be conducted together with the Centre for Proteome Research (CPR) and Centre for Cellular Imaging (CCI), respectively; two of the Shared Research Facilities (SRFs) at the University of Liverpool.

The Department of Molecular & Clinical Cancer Medicine (MCCM) has several researchers working on pancreatic cancer, who will facilitate a collaborative environment and will provide insight and experience to the project. Furthermore, the Atherton Lab shares meetings with two neighbouring labs working on cell-ECM adhesion and motility. The PhD student will be expected to fully engage with opportunities to present their research during these meetings.

Project Structure:

Year 1 – training in techniques, writing a literature review to become familiar with the background knowledge of the project, conducting initial pilot experiments (BioID and microscopy), generating CRISPR cell lines;

Year 2 – designing and conducting experiments to test hypothesis;

Year 3/4 – finalising experiments for the thesis, publication of results in leading international journals, preparation of the thesis.

For expressions of interest and to discuss the project in further detail, please email your CV and a cover letter highlighting motivation and achievements to date, to Paul Atherton: paul.atherton@liverpool.ac.uk