Homeostatic and tumourigenic activity of SOX2+ pituitary stem cells is controlled by the LATS/YAP/TAZ cascade
Abstract
SOX2 positive pituitary stem cells (PSCs) are specified embryonically and persist throughout life, giving rise to all pituitary endocrine lineages. We have previously shown the activation of the STK/LATS/YAP/TAZ signalling cascade in the developing and postnatal mammalian pituitary. Here, we investigate the function of this pathway during pituitary development and in the regulation of the SOX2 cell compartment. Through loss- and gain-of-function genetic approaches, we reveal that restricting YAP/TAZ activation during development is essential for normal organ size and specification from SOX2+ PSCs. Postnatal deletion of LATS kinases and subsequent upregulation of YAP/TAZ leads to uncontrolled clonal expansion of the SOX2+ PSCs and disruption of their differentiation, causing the formation of non-secreting, aggressive pituitary tumours. In contrast, sustained expression of YAP alone results in expansion of SOX2+ PSCs capable of differentiation and devoid of tumourigenic potential. Our findings identify the LATS/YAP/TAZ signalling cascade as an essential component of PSC regulation in normal pituitary physiology and tumourigenesis.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
Medical Research Council (MR/L016729/1)
- Cynthia Lilian Andoniadou
Lister Institute of Preventive Medicine (Prize Fellowship 2016)
- Cynthia Lilian Andoniadou
Deutsche Forschungsgemeinschaft (CRC/Transregio 205/1)
- Stefan R Bornstein
- Cynthia Lilian Andoniadou
Guy's and St Thomas' Charity (Prize PhD Programme)
- Emily J Lodge
Deutsche Forschungsgemeinschaft (GRK 2251)
- Stefan R Bornstein
- Cynthia Lilian Andoniadou
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in accordance to UK Home Office Regulations and experimental procedures were approved by the King's College Ethical Review Process.
Copyright
© 2019, Lodge 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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