This obviously teratogenic effect of cabozantinib underscores the targeting of CSC signaling, because stem cell and developmental signaling is strongly related.36 Most importantly, cabozantinib has already been clinically used for the successful treatment of prostate cancer bone metastasis, efficiently reduced metastasis in bone scans and decreased bone pain.30 These clinical data together with our results suggest the clinical evaluation of cabozantinib as a new therapeutic option to target the tumorigenic c-Met+ stromal population of GCTB. This evidence concerns the gene MET and prostate cancer.