Activation of Hedgehog signaling in mesenchymal stem cells induces cartilage and bone tumor formation via Wnt/β-Catenin
- Shanghai Jiao Tong University, China
- Shanghai Jiao Tong University Affiliated Sixth People's Hospital, China
- Harvard School of Dental Medicine, United States
Abstract
Indian Hedgehog (IHH) signaling, a key regulator of skeletal development, is highly activated in cartilage and bone tumors. Yet deletion of Ptch1, encoding an inhibitor of IHH receptor Smoothened (SMO), in chondrocyte or osteoblasts does not cause tumorigenesis. Here, we show that Ptch1 deletion in mice Prrx1+ mesenchymal stem/stromal cells (MSCs) promotes MSC proliferation and osteogenic and chondrogenic differentiation but inhibits adipogenic differentiation. Moreover, Ptch1 deletion led to development of osteoarthritis-like phenotypes, exostoses, enchondroma, and osteosarcoma in Smo-Gli1/2-dependent manners. The cartilage and bone tumors are originated from Prrx1+ lineage cells and express low levels of osteoblast and chondrocyte markers, respectively. Mechanistically, Ptch1 deletion increases the expression of Wnt5a/6 and leads to enhanced b-Catenin activation. Inhibiting Wnt/b-Catenin pathway suppresses development of skeletal anomalies including enchondroma and osteosarcoma. These findings suggest that cartilage/bone tumors arise from their early progenitor cells and identify the Wnt/b-Catenin pathway as a pharmacological target for cartilage/bone neoplasms.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
National Natural Science Foundation of China (81373210)
- Baojie Li
National Natural Science Foundation of China (81520108012)
- Baojie Li
National Natural Science Foundation of China (91542120)
- Baojie Li
National Key Research and Development Program of China (2017YFA0103602)
- Baojie Li
Schaefer Research Scholarship
- Baojie Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mouse work was carried out following the recommendations from the NationalResearch Council Guide for the Care and Use of Laboratory Animals, with the protocols approved by the Institutional Animal Care and Use Committee of Shanghai, China [SYXK (SH) 2011-0112]. All surgery was performed under sodium pentobarbital anesthesia, and every effort was made to minimize suffering.
Copyright
© 2019, Deng 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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Activation of Hedgehog signaling in mesenchymal stem cells induces cartilage and bone tumor formation via Wnt/β-Catenin
eLife 8:e50208.
https://doi.org/10.7554/eLife.50208
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