SPINK1 and hepatocellular carcinoma: Knockdown of SPINK1 also diminished tumorigenicity in vivo, with a marked decrease in tumor incidence and tumor-initiating frequency (Table 1), concomitant with an increased tumor latency (Table 1, Fig. 4d) and tumor-free survival (Fig. 4e), than HCC cells expressing the non-target scrambled control.