SLFN5 and papillary renal cell carcinoma: Interestingly, IFN-I substantially upregulates SLFN5 in malignant melanoma cells [62], in normal renal proximal tubule epithelial cells (RPTEC), and human renal adenocarcinoma cells (786-O and ACHN RCC cells), with minimal or no induction of other human Schlafens [62].