MICA: The network of class I PI3K interacting proteins is dramatically rewired in a PTEN-/- mouse model of prostate cancer. What are the implications?
Lead Research Organisation:
Babraham Institute
Department Name: Signalling
Abstract
Cancer is a disease caused by accumulation of mutations that change the cancer cells in ways that allow them to avoid the normal restraints on their growth, survival and proliferation. Despite this simple truth understanding how mutations give cancer cells an advantage can be difficult to address yet is critical to creating strategies to kill cancer cells selectively. The major problems arise from the fact there are many changes in cancer cells that are merely reactions to the key driving events and actually make no difference to cancer progression. This project aims to understand how loss of a gene that normally resists cancer (PTEN) and is very commonly a key causal event in prostate cancer gives cancer cells an advantage. We have assembled a large amount of unpublished data using a combination of new genetic strategies to dissect signalling inside normal and cancerous mouse prostate cells. This work has revealed a totally unappreciated mechanism by which loss of PTEN can give prostate (or potentially other cell types in which PTEN is lost) new properties that help them avoid normal restraints on their growth, survival and proliferation. The mechanisms work like an in-built growth accelerator that partially bypasses the need for the driver to push on the gas pedal. We propose to do this work using a mouse model of cancer, and cultured cells derived from them, where it is possible to make single mutations and study their impacts in isolation from many other mutations and changes that have accumulated in human cancers. We will test if genetically removing the molecules that constitute the in-built accelerator mechanism slows cancer progression. Through this strategy we can build a detailed understanding of the key events causing or enabling cancer progression and hence focus efforts into creating new therapeutics into right places.
Technical Summary
Mutations in many components of the class I PI3K signalling pathway support tumour progression and this has led to major investment in the development of PI3K inhibitors. Despite this focus and the vast body of data that has defined the proteins that CAN regulate class I PI3Ks, the network of molecules that actually DO perform this role in vivo, either in healthy tissues or in cancers, remains largely unknown.
Loss of the tumour-suppressor and PIP3-phosphatase, PTEN, leads to chronic activation of class I PI3K signalling and is a common occurrence in human cancers generally (11.8% of analysed tumours) and prostate cancer specifically (13.6%, early and over 60% late, stage).
We have unpublished proteomic data, obtained from mice expressing endogenously-tagged class I PI3K components, that for the first time reveals the proteins that interact with the class I PI3K regulatory subunits in healthy compared to PTEN-null mouse prostate (3 month, Hi-grade PIN stage). We find evidence of substantial rewiring upstream of PI3K activation in the PTEN-null tissue, including; a dramatic decrease in association of IRS1 (Insulin Receptor Substrate 1) and increases in interactions with the poorly characterised molecules AFAP1L2 (XB130) and PLEKHS1, but little change in association with cell surface receptors. We hypothesise that these events drive reduced insulin responsiveness/dependency and, through the molecular properties of AFAP1L2 and PLEKHS1, increased receptor-independent, PIP3-driven 'feed-forward' augmentation of PIP3 signalling and tumour progression. We aim to investigate the mechanisms that lead to this rewiring and its implications for prostate cancer.
Loss of the tumour-suppressor and PIP3-phosphatase, PTEN, leads to chronic activation of class I PI3K signalling and is a common occurrence in human cancers generally (11.8% of analysed tumours) and prostate cancer specifically (13.6%, early and over 60% late, stage).
We have unpublished proteomic data, obtained from mice expressing endogenously-tagged class I PI3K components, that for the first time reveals the proteins that interact with the class I PI3K regulatory subunits in healthy compared to PTEN-null mouse prostate (3 month, Hi-grade PIN stage). We find evidence of substantial rewiring upstream of PI3K activation in the PTEN-null tissue, including; a dramatic decrease in association of IRS1 (Insulin Receptor Substrate 1) and increases in interactions with the poorly characterised molecules AFAP1L2 (XB130) and PLEKHS1, but little change in association with cell surface receptors. We hypothesise that these events drive reduced insulin responsiveness/dependency and, through the molecular properties of AFAP1L2 and PLEKHS1, increased receptor-independent, PIP3-driven 'feed-forward' augmentation of PIP3 signalling and tumour progression. We aim to investigate the mechanisms that lead to this rewiring and its implications for prostate cancer.
Planned Impact
The main beneficiaries will be:
1. Academics: This is dealt with more completely in the section Academic Beneficiaries.
2. The two staff employed directly on the grant.
3. Industry: including our MICA-partner AstraZeneca and the pharmaceutical sector more broadly.
4. The General public.
5. Clinicians.
6. The MRC
7. Our host organisation, the Babraham Institute
They will benefit in the following ways:
1. Academics. The following elements of our research will have a wide spread impact in the fields of cancer biology and intracellular signalling; the technology we apply to study PI3K signalling in vivo, the results of that analysis that will reveal the endogenous network of class IA PI3K regulators in vivo for the first time, the loss of IRS drive to class IA PI3Ks in the context of loss of PTEN may be a widespread phenomenon in cancer and an important event in tumour progression and the increased association of the poorly understood PI3K adaptors PLEKHS1 and AFAP1L2 in the absence of PTEN in mouse prostate may well be informative for a number of other types of cancer. The project will also create new directions for academic research; in cancer biology generally and prostate cancer specifically, these are very poorly understood and the communication of the results of this project will have a significant impact on knowledge within the public domain and will encourage other academic groups to enter these important field.
2. The named PDRA on the project will learn additional skills in cancer biology, exploitation and interrogation of mouse models of cancer and organoid culture and manipulation and transferable skills in executing and communicating a curiosity-led, but target-driven, project that will be relevant to several potential careers, including basic research, the pharmaceutical sector, scientific administration and policy making. The interactions with the MICA-partner will also give them an invaluable insight into business and life in the pharmaceutical industry. The un-named research technician will learn a wide range of important skills, particularly in simple molecular biology, management of mouse breeding and colonies and genotyping, and establishing and maintaining prostate organoid cultures.
3. Industry. We hope to identify new therapeutic targets to treat cancer and to provide a deeper understanding of the mechanisms underpinning tumour progression. Early access to the results of this work will give our MICA-partners AstraZeneca a direct competitive advantage both through their own appreciation of the cancer progression process and through the opportunity to license IP generated in the project. Many of these benefits will filter down to the broader pharmaceutical community through our communication activities, although this will be slower. This will directly impact the competitiveness of our collaborators in the commercial sector and their wider organisations and will contribute to the perception that Cambridge and the UK are centres of excellent academic/commercial collaboration that will serve to bring in more R & D investment into the region generally.
4. The general public. In the short to medium term as recipients of our public engagement activities giving them a better understanding of research and cancer biology. In the longer term as patients receiving potentially improved treatments based on our findings.
5. Clinicians. Through improved insights into the processes driving prostate tumour progress, potential new treatments or diagnostic tests.
6. The MRC. Through delivery of their strategic priorities, particularly in terms of our results improving understanding of a socio-economically important disease and our knowledge exchange and commercialisation activities as outlined in the Pathways to Impact, Communication and Academic Beneficiaries sections.
7.The Babraham Institute. Through our work delivering their plans in commercialisation, knowledge exchange and impact activities.
1. Academics: This is dealt with more completely in the section Academic Beneficiaries.
2. The two staff employed directly on the grant.
3. Industry: including our MICA-partner AstraZeneca and the pharmaceutical sector more broadly.
4. The General public.
5. Clinicians.
6. The MRC
7. Our host organisation, the Babraham Institute
They will benefit in the following ways:
1. Academics. The following elements of our research will have a wide spread impact in the fields of cancer biology and intracellular signalling; the technology we apply to study PI3K signalling in vivo, the results of that analysis that will reveal the endogenous network of class IA PI3K regulators in vivo for the first time, the loss of IRS drive to class IA PI3Ks in the context of loss of PTEN may be a widespread phenomenon in cancer and an important event in tumour progression and the increased association of the poorly understood PI3K adaptors PLEKHS1 and AFAP1L2 in the absence of PTEN in mouse prostate may well be informative for a number of other types of cancer. The project will also create new directions for academic research; in cancer biology generally and prostate cancer specifically, these are very poorly understood and the communication of the results of this project will have a significant impact on knowledge within the public domain and will encourage other academic groups to enter these important field.
2. The named PDRA on the project will learn additional skills in cancer biology, exploitation and interrogation of mouse models of cancer and organoid culture and manipulation and transferable skills in executing and communicating a curiosity-led, but target-driven, project that will be relevant to several potential careers, including basic research, the pharmaceutical sector, scientific administration and policy making. The interactions with the MICA-partner will also give them an invaluable insight into business and life in the pharmaceutical industry. The un-named research technician will learn a wide range of important skills, particularly in simple molecular biology, management of mouse breeding and colonies and genotyping, and establishing and maintaining prostate organoid cultures.
3. Industry. We hope to identify new therapeutic targets to treat cancer and to provide a deeper understanding of the mechanisms underpinning tumour progression. Early access to the results of this work will give our MICA-partners AstraZeneca a direct competitive advantage both through their own appreciation of the cancer progression process and through the opportunity to license IP generated in the project. Many of these benefits will filter down to the broader pharmaceutical community through our communication activities, although this will be slower. This will directly impact the competitiveness of our collaborators in the commercial sector and their wider organisations and will contribute to the perception that Cambridge and the UK are centres of excellent academic/commercial collaboration that will serve to bring in more R & D investment into the region generally.
4. The general public. In the short to medium term as recipients of our public engagement activities giving them a better understanding of research and cancer biology. In the longer term as patients receiving potentially improved treatments based on our findings.
5. Clinicians. Through improved insights into the processes driving prostate tumour progress, potential new treatments or diagnostic tests.
6. The MRC. Through delivery of their strategic priorities, particularly in terms of our results improving understanding of a socio-economically important disease and our knowledge exchange and commercialisation activities as outlined in the Pathways to Impact, Communication and Academic Beneficiaries sections.
7.The Babraham Institute. Through our work delivering their plans in commercialisation, knowledge exchange and impact activities.
Organisations
- Babraham Institute (Lead Research Organisation)
- AstraZeneca (Collaboration)
- Cardiff University (Collaboration)
- Astex Pharmaceuticals (Collaboration)
- Cold Spring Harbor Laboratory (CSHL) (Collaboration)
- Addenbrooke's Hospital (Collaboration)
- Vrije Universiteit Brussel (Collaboration)
- AstraZeneca (United Kingdom) (Project Partner)
Publications
Chessa TAM
(2023)
PLEKHS1 drives PI3Ks and remodels pathway homeostasis in PTEN-null prostate.
in Molecular cell
Luff DH
(2021)
PI3Kd Forms Distinct Multiprotein Complexes at the TCR Signalosome in Naïve and Differentiated CD4+ T Cells.
in Frontiers in immunology
Tsolakos N
(2018)
Quantitation of class IA PI3Ks in mice reveals p110-free-p85s and isoform-selective subunit associations and recruitment to receptors.
in Proceedings of the National Academy of Sciences of the United States of America
Description | Eline Mol and Laura Ligthart |
Organisation | Vrije Universiteit Brussel |
Country | Belgium |
Sector | Academic/University |
PI Contribution | We trained 2 dutch students who worked remotely in phosphoinositide research data analysis and bioinformatic analysis to contribute towards their degrees. |
Collaborator Contribution | They analysed raw data obtained from various assys in the lab studying plekhs1 function and performed bioinformatics analysis of Plekhs1. |
Impact | Data analysed will contribute to a paper, students obtained high marks for their project work and passed degrees with high marks |
Start Year | 2020 |
Description | Helen Pearson |
Organisation | Cardiff University |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Defined new role for plekhs1 in prostate tumour progression |
Collaborator Contribution | Provided prostate samples from H1047R expressing mice |
Impact | On going paper under review |
Start Year | 2021 |
Description | John Lyons Astex |
Organisation | Astex Pharmaceuticals |
Department | Astex Therapeutics Ltd |
Country | United Kingdom |
Sector | Private |
PI Contribution | Early discussion of PI3K signalling concepts in tumourigenesis |
Collaborator Contribution | novel data and ideas |
Impact | none yet possibly a grant application and patent application |
Start Year | 2023 |
Description | Lloyd Trotmann |
Organisation | Cold Spring Harbor Laboratory (CSHL) |
Department | Cancer Centre |
Country | United States |
Sector | Academic/University |
PI Contribution | We have performed proteomic and cellular studies of PTEN deficient mouse prostate tissue |
Collaborator Contribution | They performed PET imaging of glucose uptake into mouse prostate tissues control and cancer models |
Impact | Shared results and discussion about further work |
Start Year | 2018 |
Description | Plekhs1 |
Organisation | AstraZeneca |
Country | United Kingdom |
Sector | Private |
PI Contribution | We identified novel roles fro plekhs1 in control of tumour progression |
Collaborator Contribution | They provided , reagents , experience and samples relevant to prostate tumour progression |
Impact | Only just starting |
Start Year | 2022 |
Description | Sabina Cosulich- prostate project |
Organisation | AstraZeneca |
Country | United Kingdom |
Sector | Private |
PI Contribution | We have researched into the possible role of PLEKHS1 in prostate tumour progression |
Collaborator Contribution | Access to unpublished data, advise, and funding via an MRC MICA award |
Impact | The results thus far are revealing a new approach to targeting the pi3k pathway and are being prepared for publication in 2020. |
Start Year | 2016 |
Description | Vincent Gnanapragasam |
Organisation | Addenbrooke's Hospital |
Department | Department of Oncology |
Country | United Kingdom |
Sector | Hospitals |
PI Contribution | We are measuring and analysing PIP3 and related lipids in prostate samples |
Collaborator Contribution | Advice over prostate sampling, archived material |
Impact | RCUK grant awarded to support our collaboration. |
Start Year | 2016 |
Title | Modulating plekhs1 activity in a cell |
Description | That modulation of plekhs1 activity may be a useful strategy in reducing tumour progression |
IP Reference | 2304156.9 |
Protection | Patent / Patent application |
Year Protection Granted | 2023 |
Licensed | No |
Impact | Further funding leading to funded collaboration with AstraZeneca |
Description | Comberton Village college AA, TC and PTH |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | A carrels in bioscience discussion involving a group leader, a post doc and a PhD student from our lab. They meet with a yr 12 (17yrs old) cohort at Comberton VC a local school. |
Year(s) Of Engagement Activity | 2022 |
Description | Escape room installation used in 2 events |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | A "signalling" escape room installation that was presented at the Latitude Music Festival, and the Cambridge science Festival |
Year(s) Of Engagement Activity | 2019,2020 |
Description | Production of research video |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Produced an animated video overview of current and ongoing research around PI3K and wider cell signalling. Video published on Institute youtube account and promoted to public audiences as well as other sector stakeholders. |
Year(s) Of Engagement Activity | 2021 |
Description | Schools day Feb 2018 Babraham Institute |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Schools |
Results and Impact | Discussion, question/answer and experiment to show how neutrophils contribute to immune defence and a broader dialogue about the societal signifcance of research and the types of jobs that can be involved. |
Year(s) Of Engagement Activity | 2014,2015,2016,2017,2018 |
Description | Work Experience students |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | School students came into our department to shadow researchers and get involved in discussions about research and see our facilities. |
Year(s) Of Engagement Activity | 2018 |
Description | science spotlight public talk |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | On line presentation targeted to adult community groups in an area of deprivation |
Year(s) Of Engagement Activity | 2021 |