GDF-15 is a biomarker of aggressiveness and is down-regulated by the mTOR inhibitor sirolimus through ATF4 and ATF5 suppression in epithelioid hemangioendothelioma.

Growth and differentiation factor-15 (GDF-15), a member of the TGF-β superfamily, exhibits elevated expression in various tumor types, often linked to disease aggressiveness. In this study, which used patient-derived xenografts and paired cell lines of epithelioid hemangioendothelioma (EHE), it was found that EHE cells produce and release GDF-15. Furthermore, the mTOR inhibitor sirolimus was observed to inhibit GDF-15 expression and release by down-regulating ATF4 and ATF5 transcription factors. To assess the clinical relevance of GDF-15 in EHE, which can manifest as both relatively indolent and exceptionally aggressive forms, circulating GDF-15 levels were assessed in two independent cohorts of EHE patients, one retrospective and one prospective. The results provided evidence of an association between circulating GDF-15 levels and the aggressiveness of EHE. In summary, these findings suggest that GDF-15 can serve as a biomarker for EHE aggressiveness and may have implications for monitoring the effectiveness of sirolimus in EHE patients. mRNA profiles of PDX and clinical sample were generated on an Illumina NextSeq500 sequencer.