1. E-cadherin-deficient cells have synthetic lethal vulnerabilities in plasma membrane organisation, dynamics and function
- Author
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Bryony J. Telford, Michael A. Black, Lawrence Harris, Andrew Single, S. Thomas Kelly, Gary B. Evans, Nicola Bougen-Zhukov, Parry Guilford, Henry Beetham, Sophie K. Currie, Tom Brew, Cassie E. Stylianou, Tanis D Godwin, and Augustine Chen
- Subjects
Cancer Research ,Synthetic lethality ,Breast Neoplasms ,Endocytosis ,medicine.disease_cause ,CDH1 ,03 medical and health sciences ,0302 clinical medicine ,Antigens, CD ,Stomach Neoplasms ,Cell Line, Tumor ,medicine ,Lethal allele ,Humans ,Genetic Predisposition to Disease ,PI3K/AKT/mTOR pathway ,Germ-Line Mutation ,G protein-coupled receptor ,Mutation ,Diffuse gastric cancer ,biology ,business.industry ,Cholera toxin ,Cell Membrane ,Gastroenterology ,E-cadherin ,General Medicine ,Cadherins ,Cell biology ,Protein Transport ,Oncology ,030220 oncology & carcinogenesis ,biology.protein ,030211 gastroenterology & hepatology ,Original Article ,Female ,business ,Plasma membrane - Abstract
Background The E-cadherin gene (CDH1) is frequently mutated in diffuse gastric cancer and lobular breast cancer, and germline mutations predispose to the cancer syndrome Hereditary Diffuse Gastric Cancer. We are taking a synthetic lethal approach to identify druggable vulnerabilities in CDH1-mutant cancers. Methods Density distributions of cell viability data from a genome-wide RNAi screen of isogenic MCF10A and MCF10A-CDH1−/− cells were used to identify protein classes affected by CDH1 mutation. The synthetic lethal relationship between selected protein classes and E-cadherin was characterised by drug sensitivity assays in both the isogenic breast MCF10A cells and CDH1-isogenic gastric NCI-N87. Endocytosis efficiency was quantified using cholera toxin B uptake. Pathway metagene expression of 415 TCGA gastric tumours was statistically correlated with CDH1 expression. Results MCF10A-CDH1−/− cells showed significantly altered sensitivity to RNAi inhibition of groups of genes including the PI3K/AKT pathway, GPCRs, ion channels, proteosomal subunit proteins and ubiquitinylation enzymes. Both MCF10A-CDH1−/− and NCI-N87-CDH1−/− cells were more sensitive than wild-type cells to compounds that disrupted plasma membrane composition and trafficking, but showed contrasting sensitivities to inhibitors of actin polymerisation and the chloride channel inhibitor NS3728. The MCF10A-CDH1−/− cell lines showed reduced capacity to endocytose cholera toxin B. Pathway metagene analysis identified 20 Reactome pathways that were potentially synthetic lethal in tumours. Genes involved in GPCR signalling, vesicle transport and the metabolism of PI3K and membrane lipids were strongly represented amongst the candidate synthetic lethal genes. Conclusions E-cadherin loss leads to disturbances in receptor signalling and plasma membrane trafficking and organisation, creating druggable vulnerabilities. Electronic supplementary material The online version of this article (10.1007/s10120-018-0859-1) contains supplementary material, which is available to authorised users.
- Published
- 2018