NOTCH1 and Intervertebral disk degeneration: To analyze the biological connection between hypoxia-related hub genes (RCOR2, STAT3, NOTCH1, SP1, SART1, PRIM1, LYAR, KIF20B, MSH2) and the immune microenvironment of intervertebral disc degeneration, we utilized the ssGSEA algorithm to estimate the gene degree of immune cells in the sample and then calculated the correlation between key genes and immune cells according to the “Spearman” method.