The anti-leukemia effect of SHK was firstly reported by Yoon and colleagues in 1999, in which SHK was found to induce death of HL-60 human promyelocytic leukemia cell line via inducing apoptosis as shown by increased DNA fragmentation and percentage of hypodiploid cells companied with activation of caspase-3 (Yoon et al., 1999). Here, SHPK is linked to acute promyelocytic leukemia.