Background acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia (AML) marked by a high incidence of coagulopathy. Podoplanin (PDPN), a glycoprotein involved in platelet activation through interaction with CLEC-2, has been recently identified on leukemic promyelocytes and suggested as a potential contributor to APL coagulopathy. Identification of novel biomarkers and therapeutic targets for APL coagulopathy can potentially improve the outcomes of this condition.

Aim to explore whether levels of soluble PDPN (sPDPN) in plasma are different in APL, and to evaluate its association with laboratory and clinical outcomes in these patients.

Methods samples were obtained from consecutive patients with APL at the time of diagnosis in an academic hospital. Biobank samples from 35 patients with non-APL AML matched for age and sex were used as comparators. Circulating PDPN levels were measured in plasma using a commercial ELISA. The study was approved by the IRB and all participants provided written informed consent.

Results APL patients showed significantly higher plasma sPDPN concentrations compared non-APL AML. Using the median sPDPN value as a cutoff, a higher proportion of APL patients presented elevated levels. sPDPN levels correlated with CD40L among APL cases, but not among non-APL AML patients, suggesting a possible interaction in with thrombo-inflammatory activation pathways.

Conclusion these findings represent a proof-of-concept that measuring sPDPN in plasma samples can contribute to the diagnosis of APL, while also providing novel data on the association of PDPN with the pathogenesis of APL coagulopathy.

The authors have declared no competing interest.

This study was funded by the Sao Paulo Research Foundation (FAPESP), grants 2020/05985/9, 2022/13216/0 and 2023/03765/0. FAEPEX-Unicamp grant 2404/2020 and 2633/23; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brasil (CAPES), finance code 001.

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Ethics committee/IRB of UNIVERSIDADE ESTADUAL DE CAMPINAS ethical approval for this work.(CAAE: 39948520.8.1001.5404)

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