Furthermore, we tested the expression levels of some common RCC CSC biomarkers including OCT4, CD44, NANOG, and MYC (Hu et al., 2017; Qian et al., 2018; Rasti et al., 2018), and found that the ING4 overexpression significantly promoted the mRNA expression levels of almost all stem cell markers in Ketr-3 and 786-O cells compared to the respective controls (Figure 2A). Here, CD44 is linked to renal cell carcinoma.