TSP2 acts as a suppresser of cell invasion, migration and angiogenesis in medulloblastoma by inhibiting the Notch signaling pathway.

Medulloblastoma (MB) represents a fatal malignancy often occurring in children. Angiogenesis is a hallmark of the progression of MB. Over the past decade, investigators have attempted to develop more effective and less toxic anti-angiogenic strategies to treat MB. Thrombospondin (TSP) family is observed to be a key regulator of angiogenesis. Thus, the current study aimed to elucidate the function of TSP2 in patients with MB and the underlying mechanism. The expression of TSP2, Notch1 and VEGF in MB and adjacent tissues collected from clinical samples as well as a MB cell line (Daoy) was examined. The results demonstrated that in the MB tissues and Daoy cells, TSP2 was downregulated, while Notch1 and VEGF were upregulated. Then, after the Daoy cells were treated with TSP2 silencing, TSP2 overexpression, or Notch signaling pathway inhibition, a series of in vitro cell experiments were performed to verify the interaction between TSP2 and Notch signaling pathway, and to examine the abilities of cell proliferation, migration, invasion, and tube formation. Upregulation of TSP2 was observed to lead to the downregulation of the Notch signaling pathway. Moreover, cells overexpressing TSP2 exhibited diminished proliferation, invasion, migration, and tube formation. In addition, a significant attenuation of tumor growth and angiogenesis was identified in vivo in the Daoy cells overexpressing TSP2 inoculated in nude mice. Taken together, the key findings of this study revealed the inhibitory role of TSP2 in the development of MB via blockade of the Notch signaling pathway, highlighting its potential as a treatment target for MB treatment.