Importantly, osteosarcoma tissues were divided into the DXR-resistant group (treatment-resistant, N = 36) and the DXR-sensitive group (treatment-responsive, N = 24) depending on the sensitivity of osteosarcoma patients to DXR, and we found that circSAMD4A (Figure 1c) and KLF8 (Figure 1k and o) were notably higher, while miR-218-5p (Figure 1g) was lower in the treatment-resistant group than those in the treatment-responsive group. Here, KLF8 is linked to osteosarcoma.