In the same year, the human cytokine array method was utilized by Mambet et al. to investigate plasma cytokine levels in a cohort of young (<35 years) MPN patients (N = 10 PV, N = 10 ET, and N = 10 prePMF): angiopoietin-1, Dickkopf-related protein (Dkk)-1, Epidermal Growth Factor (EGF), IP-9, and PDGF were found elevated as compared to controls, with Dkk-1 levels showing the highest potential for discrimination between MPN subtypes (prePMF > PV > ET) [73]. Here, EGF is linked to myeloproliferative disorder.