Figure 7.The expression levels of four hub genes were shown by boxplots. (A) Expression of the hub genes in the GSE114007 dataset, HMGB2, CDKN1A, JUN, andDDIT3 expression were all down-regulated in OA samples. (B) The expression of the Hub gene in an external GSE169077 data set (**p < 0.01; ***p < 0.001).