CYRI-B mediated macropinocytosis drives metastasis via lysophosphatidic acid receptor uptake
Abstract
Pancreatic ductal adenocarcinoma carries a dismal prognosis, with high rates of metastasis and few treatment options. Hyperactivation of KRAS in almost all tumours drives RAC1 activation, conferring enhanced migratory and proliferative capacity as well as macropinocytosis. Macropinocytosis is well understood as a nutrient scavenging mechanism, but little is known about its functions in trafficking of signaling receptors. We find that CYRI-B is highly expressed in pancreatic tumours in a mouse model of KRAS and p53-driven pancreatic cancer. Deletion of Cyrib (the gene encoding CYRI-B protein) accelerates tumourigenesis, leading to enhanced ERK and JNK-induced proliferation in precancerous lesions, indicating a potential role as a buffer of RAC1 hyperactivation in early stages. However, as disease progresses, loss of CYRI-B inhibits metastasis. CYRI-B depleted tumour cells show reduced chemotactic responses to lysophosphatidic acid, a major driver of tumour spread, due to impaired macropinocytic uptake of the lysophosphatidic acid receptor-1. Overall, we implicate CYRI-B as a mediator of growth and signaling in pancreatic cancer, providing new insights into pathways controlling metastasis.
Data availability
All Western blot and numerical data generated or analysed during this study are included in the manuscript and supporting files; source data files have been provided for all graphs and western blots.
Article and author information
Author details
Funding
Cancer Research UK (A24452)
- Laura M Machesky
Cancer Research UK (A17196)
- Amelie Juin
- Jamie A Whitelaw
- Nikki R Paul
- Loic Fort
- Colin Nixon
- Heather J Spence
- Sheila Bryson
- Laura M Machesky
Cancer Research UK (A31287)
- Amelie Juin
- Jamie A Whitelaw
- Nikki R Paul
- Loic Fort
- Colin Nixon
- Heather J Spence
- Sheila Bryson
- Laura M Machesky
EPSRC UKRI (EP/T00213/1)
- Laura M Machesky
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Erica A Golemis, Fox Chase Cancer Center, United States
Ethics
Animal experimentation: Mice were maintained by the Biological Services Unit staff according to the UK home office regulations and instructions. The experiments were approved by the local Animal Welfare and Ethical Review Body (AWERB) of the University of Glasgow and performed under UK Home office licence PE494BE48 to LMM.
Version history
- Received: September 26, 2022
- Accepted: May 6, 2024
- Accepted Manuscript published: May 7, 2024 (version 1)
Copyright
© 2024, Nikolaou et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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