PCSK1 and glioma: As figure 2 C showed, the decreased viability of C6 glioma cells caused by 3.0 μmol/L and 6.0 μmol/L shikonin was improved by pretreatment with Nec-1 (a specific inhibitor of necroptosis) to 92.3% and 82.9% at 1.5 h and 84.4% and 78.6% at 3.0 h, respectively.