The expression of all RISC components, namely trans-activation response (TAR) RNA binding protein 1 (TRBP1), TRBP2, Protein ACTivator of the interferon-induced protein kinase (PACT), Argonaute RISC Catalytic Component-1 (AGO1) and Component-2 (AGO2), metadherin, and staphylococcal nuclease and Tudor domain-containing-1 (SND1), were investigated, showing a significant decrease in HS lesional skin compared to healthy controls and thus demonstrating the causative role of miRNAs in HS pathogenesis [55]. The gene discussed is AGO2; the disease is histiocytic sarcoma.