Hedgehog signaling induces osteosarcoma development through Yap1 and H19 overexpression

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Osteosarcoma is a common bone tumor with an unclear genetic basis.
• Hedgehog (Hh) signaling is implicated in various cancers, but its role in osteosarcoma is not fully understood.

Purpose of the Study:

• To investigate the role of upregulated Hedgehog (Hh) signaling in osteosarcoma development.
• To elucidate the molecular mechanisms underlying Hh-induced osteosarcoma, focusing on Yap1 and H19.

Main Methods:

• Generation of genetically-engineered mouse models with modulated Hh signaling in osteoblasts.
• Analysis of tumor development, cell proliferation, and gene expression (Yap1, H19).
• Inhibition of Hh signaling and Yap1 knockdown to assess their impact on tumor progression.

Main Results:

• Upregulated Hh signaling in mature osteoblasts leads to malignant osteosarcoma in mice.
• Tumor cells exhibit osteoblastic characteristics, high proliferation, and tumorigenic potential.
• Hedgehog signaling upregulates the oncogene Yap1 and lncRNA H19, both critical for osteosarcoma progression.

Conclusions:

• Aberrant Hh signaling in mature osteoblasts is a key driver of osteoblastic osteosarcoma.
• The Hh-Yap1-H19 axis is crucial for osteosarcoma pathogenesis.
• Targeting Hh signaling or Yap1 may offer therapeutic strategies for osteosarcoma.