Interestingly, in renal carcinoma cells, Hif1α and CXCR4 have been shown to take part in a feed forward loop for nuclear translocation such that, via a direct physical interaction between the two proteins, nuclear accumulation of CXCR4 favors entry of HIF-1α and HIF-1α then further promotes CXCR4 expression (Bao et al., 2019). This evidence concerns the gene HIF1A and renal carcinoma.