SPOCK1 and renal cell carcinoma: We first evaluated endogenous levels of SPOCK1 in a set of RCC cell lines including ccRCC (Caki-1 and 786-O) and pRCC (ACHN and Caki-2) cells by Western blotting and found that ccRCC cells expressed higher SPOCK1 levels compared to the pRCC cell lines (Figure 2A).