PCSK1 and glioma: Furthermore, in the process of shikonin-induced necroptosis of the glioma cell, when specific inhibitors such as Nec-1 and GSK872 are used to inhibit RIP1 and RIP3, or with knockdown of RIP1 and RIP3 using siRNA, the expression of CypA can be inhibited; this proved that RIP1 and RIP3 can regulate CypA.