In the current study, we first investigated the role of HPIP in RCC growth and metastasis both in vitro and in vivo. More importantly, we identified casein kinase 1α (CK1α), a critical regulator of tumorigenesis and metastasis, as a novel HPIP-interacting protein, thus linking the oncogenic ability of HPIP to its interaction with CK1α. Here, CSNK1A1 is linked to renal cell carcinoma.