TFE3 and neoplasm: These findings are entirely consistent with the fact that SFPQ is the most common TFE3 fusion partner in human PEComas and further support the fidelity of current MiT/TFE mouse tumor models, where the PRCC-TFE3 model shows partial retention of PAX8 and epithelial features consistent with tRCC4, while our SFPQ-TFE3 model most closely approximates a malignant epithelioid PEComa phenotype.