Knockdown of MSI2 inhibits metastasis by interacting with caveolin-1 and inhibiting its ubiquitylation in human NF1-MPNST cells

Malignant peripheral nerve sheath tumours (MPNSTs) are highly aggressive Schwann cell-derived sarcomas, and they are either associated with neurofibromatosis type 1 (NF1) or sporadic. Our previous study found that high mobility group protein A2 (HMGA2) regulates NF1-MPNST growth through Musashi-2 (MSI2); however, whether MSI2 regulates MPNST metastasis and what the mechanism is remain unclear. Here, we demonstrated that the protein caveolin-1 (CAV1) directly interacts with MSI2 in human NF1-MPNST cells. Moreover, we discovered that knockdown of MSI2 induces CAV1 protein expression by inhibiting its ubiquitylation level in NF1-MPNSTs. In addition, CAV1 mediates the suppressive function of MSI2 in epithelial-mesenchymal transition, migration and invasion in vitro and metastasis in vivo. These results help to reveal the potential mechanisms of MSI2 as a target of antimetastatic treatment for human NF1-MPNST.