ABCA1 and giant cell tumor: As shown in Figure 1C, the expression levels of ABCA1 in SKCM (skin melanoma) (P > 0.05) tumour tissues were clearly lower than that in normal tissues, whereas the expression levels of ABCA1 in GBM (glioblastoma multiforme) (P < 0.05), LGG (low-grade glioma) (P < 0.05), THYM (thymic carcinoma) (P < 0.05), DLBC (diffuse large B-cell lymphoma) (P > 0.05), and TGCT (tenosynovial giant cell tumour) (P > 0.05) tumour tissues were higher than that in normal tissues.