Activation of PTHrP-cAMP-CREB1 signaling following p53 loss is essential for osteosarcoma initiation and maintenance

  1. Mannu K Walia
  2. Patricia MW Ho
  3. Scott Taylor
  4. Alvin JM Ng
  5. Ankita Gupte
  6. Alistair M Chalk
  7. Andrew CW Zannettino
  8. T John Martin
  9. Carl R Walkley  Is a corresponding author
  1. St. Vincent's Institute of Medical Research, Australia
  2. University of Adelaide, Australia

Abstract

Mutations in the P53 pathway are a hallmark of human cancer. The identification of pathways upon which p53-deficient cells depend could reveal therapeutic targets that may spare normal cells with intact p53. In contrast to P53 point mutations in other cancer, complete loss of P53 is a frequent event in osteosarcoma (OS), the most common cancer of bone. The consequences of p53 loss for osteoblastic cells and OS development are poorly understood. Here we use murine OS models to demonstrate that elevated Pthlh (Pthrp), cAMP levels and signalling via CREB1 are characteristic of both p53-deficient osteoblasts and OS. Normal osteoblasts survive depletion of both PTHrP and CREB1. In contrast, p53-deficient osteoblasts and OS depend upon continuous activation of this pathway and undergo proliferation arrest and apoptosis in the absence of PTHrP or CREB1. Our results identify the PTHrP-cAMP-CREB1 axis as an attractive pathway for therapeutic inhibition in OS.

Article and author information

Author details

  1. Mannu K Walia

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. Patricia MW Ho

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
  3. Scott Taylor

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
  4. Alvin JM Ng

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
  5. Ankita Gupte

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
  6. Alistair M Chalk

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
  7. Andrew CW Zannettino

    Myeloma Research Laboratory, School of Medicine, Faculty of Health Sciences, University of Adelaide, Adelaide, Australia
    Competing interests
    The authors declare that no competing interests exist.
  8. T John Martin

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    Competing interests
    The authors declare that no competing interests exist.
  9. Carl R Walkley

    St. Vincent's Institute of Medical Research, Fitzroy, Australia
    For correspondence
    cwalkley@svi.edu.au
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Jonathan A Cooper, Fred Hutchinson Cancer Research Center, United States

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Health and Medical Research Council, Australia and the Bureau of Animal Welfare, Victorian Government . All of the animals were handled according to approved institutional animal care and use committee (Animal Ethics Committee) protocols (#017/15) of the St. Vincent's Hospital Melbourne.

Human subjects: Primary human osteoblasts were isolated from bone marrow aspirates from the posterior iliac crest of de-identified healthy human adult donors with informed consent and consent to publish (IMVS/SA Pathology normal bone marrow donor program RAH#940911a, Adelaide, South Australia).

Version history

  1. Received: December 2, 2015
  2. Accepted: April 8, 2016
  3. Accepted Manuscript published: April 12, 2016 (version 1)
  4. Version of Record published: May 3, 2016 (version 2)

Copyright

© 2016, Walia 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.

Metrics

  • 2,509
    Page views
  • 430
    Downloads
  • 39
    Citations

Article citation count generated by polling the highest count across the following sources: Scopus, Crossref, PubMed Central.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Mannu K Walia
  2. Patricia MW Ho
  3. Scott Taylor
  4. Alvin JM Ng
  5. Ankita Gupte
  6. Alistair M Chalk
  7. Andrew CW Zannettino
  8. T John Martin
  9. Carl R Walkley
(2016)
Activation of PTHrP-cAMP-CREB1 signaling following p53 loss is essential for osteosarcoma initiation and maintenance
eLife 5:e13446.
https://doi.org/10.7554/eLife.13446

Share this article

https://doi.org/10.7554/eLife.13446

Further reading

    1. Cell Biology
    Kazuki Hanaoka, Kensuke Nishikawa ... Kouichi Funato
    Research Article

    Membrane contact sites (MCSs) are junctures that perform important roles including coordinating lipid metabolism. Previous studies have indicated that vacuolar fission/fusion processes are coupled with modifications in the membrane lipid composition. However, it has been still unclear whether MCS-mediated lipid metabolism controls the vacuolar morphology. Here, we report that deletion of tricalbins (Tcb1, Tcb2, and Tcb3), tethering proteins at endoplasmic reticulum (ER)–plasma membrane (PM) and ER–Golgi contact sites, alters fusion/fission dynamics and causes vacuolar fragmentation in the yeast Saccharomyces cerevisiae. In addition, we show that the sphingolipid precursor phytosphingosine (PHS) accumulates in tricalbin-deleted cells, triggering the vacuolar division. Detachment of the nucleus–vacuole junction (NVJ), an important contact site between the vacuole and the perinuclear ER, restored vacuolar morphology in both cells subjected to high exogenous PHS and Tcb3-deleted cells, supporting that PHS transport across the NVJ induces vacuole division. Thus, our results suggest that vacuolar morphology is maintained by MCSs through the metabolism of sphingolipids.

    1. Cell Biology
    2. Chromosomes and Gene Expression
    Monica Salinas-Pena, Elena Rebollo, Albert Jordan
    Research Article

    Histone H1 participates in chromatin condensation and regulates nuclear processes. Human somatic cells may contain up to seven histone H1 variants, although their functional heterogeneity is not fully understood. Here, we have profiled the differential nuclear distribution of the somatic H1 repertoire in human cells through imaging techniques including super-resolution microscopy. H1 variants exhibit characteristic distribution patterns in both interphase and mitosis. H1.2, H1.3, and H1.5 are universally enriched at the nuclear periphery in all cell lines analyzed and co-localize with compacted DNA. H1.0 shows a less pronounced peripheral localization, with apparent variability among different cell lines. On the other hand, H1.4 and H1X are distributed throughout the nucleus, being H1X universally enriched in high-GC regions and abundant in the nucleoli. Interestingly, H1.4 and H1.0 show a more peripheral distribution in cell lines lacking H1.3 and H1.5. The differential distribution patterns of H1 suggest specific functionalities in organizing lamina-associated domains or nucleolar activity, which is further supported by a distinct response of H1X or phosphorylated H1.4 to the inhibition of ribosomal DNA transcription. Moreover, H1 variants depletion affects chromatin structure in a variant-specific manner. Concretely, H1.2 knock-down, either alone or combined, triggers a global chromatin decompaction. Overall, imaging has allowed us to distinguish H1 variants distribution beyond the segregation in two groups denoted by previous ChIP-Seq determinations. Our results support H1 variants heterogeneity and suggest that variant-specific functionality can be shared between different cell types.