To determine whether XRN1-DCPs utilize the RNA-induced silencing complex (RISC) to target vRNA for degradation [14, 15], we used human bone osteosarcoma epithelial (U-2 OS) cells stably co-expressing mRFP-DCP1a and EGFP-AGO1 [16]. The gene discussed is XRN1; the disease is bone osteosarcoma.