Skip to Main content Skip to Navigation
Theses

L'hormone de croissance : une cytokine

Abstract : Growth hormone (GH) is a paradoxical hormone. Historically described as the major regulator of postnatal growth it is now recognised as a cytokine synthesized in many extrapituitary sites and involved in tumorigenesis. The work presented in this thesis described the characterisation and localisation of GH production in the immune system of adult and foetal rat and in different disorders of the human mammary gland. Using in situ RT-PCR, we show that autocrine/paracrine GH is involved in embryonic development as well as in breast tumour progression. We have also demonstrated in a model system that activation of JAK2 « Janus Kinase 2 » is not required for internalisation and nuclear translocation of GH but is pivotal for the removal of the hormone from the nucleus. We also studied the negative regulation of cytokine signalling and demonstrated the overexpression of CIS protein « Cytokine-Inducible SH2-containing protein » in breast disorders and 8 breast carcinoma cell lines, where it induces the inhibition of the JAK/STAT « Signal Transducer and Activator of Transcription » pathway and the activation of the MAP kinase « Mitogen Activated Protein Kinases » pathway. We finally demonstrated that CIS overexpression in breast carcinoma cells is correlated to the autocrine/paracrine production of GH. The nuclear and cytoplasmic localisation of GH and its signalling molecules might explain the multiple physiological effects of GH. Future work is now required to answer a crucial question: GH, fountain of youth or oncogene?
Complete list of metadata

https://tel.archives-ouvertes.fr/tel-00069301
Contributor : Frédérique Cohen-Adad <>
Submitted on : Wednesday, May 17, 2006 - 10:46:16 AM
Last modification on : Monday, October 19, 2020 - 11:10:43 AM
Long-term archiving on: : Saturday, April 3, 2010 - 10:33:34 PM

Identifiers

  • HAL Id : tel-00069301, version 1

Collections

Citation

Mireille Raccurt. L'hormone de croissance : une cytokine. Physiologie [q-bio.TO]. Ecole pratique des hautes études - EPHE PARIS, 2003. Français. ⟨tel-00069301⟩

Share

Metrics

Record views

709

Files downloads

7556