NNT and osteosarcoma: To integrate establish an overall effective osteosarcoma scoring model, 4 epi-lncRNAs were removed according to stepAIC, and the remaining four epi-lncRNAs (A2M-AS1, CACNA1G-AS1, LBA2-AS1, and NNT-AS1) were recruited to build a risk model (Figure 4C).