The effect of GSK-3β in arsenic-induced apoptosis of malignant tumor cells: a systematic review and meta-analysis

Arsenic has been reported to induce apoptosis in malignant tumor cells. Therefore, it has been investigated as a chemotherapy. From a mechanistic standpoint, the mitochondrial apoptosis pathway, mediated by GSK-3β, plays an important role in tumor cell apoptosis. Nonetheless, the regulation of GSK-3β by arsenic remains controversial. The study aimed to clarify the mechanism of GSK-3β in arsenic-induced apoptosis of tumor cells.We included 19 articles, which conducts the role of GSK-3β in the process of arsenic-induced tumor cell apoptosis by the meta-analysis.Compared with that of control group, the expression of GSK-3β (SMD= -0.92, 95% CI (-1.78, -0.06)), p-Akt (SMD= -5.46,95% CI (-8.67, -2.24)) were increased in the arsenic intervention group. Meanwhile, the combined treatment of arsenic and Akt agonists can inhibit p-GSK-3β. Using the dose and time subgroup analysis, it was shown that the low-dose (<5 μmol/L) and sub-chronic (>24 h) arsenic exposure could inhibit the expression of p-Akt (P < 0.05). In the subgroup analysis of GSK-3β sites, arsenic could inhibit p-Akt and GSK-3β (Ser9) (SMD = -0.95, 95% CI (-1.56, -0.33)). There was a positive dose-response relationship between arsenic and p-GSK-3β when the dose of arsenic was less than 8 μmol/L. The expression of Mcl-1 and pro-caspase-3 were decreased, while the loss of mitochondrial membrane potential and cleaved-caspase-3 increased significantly when arsenic stimulated GSK-3β (Ser9) (P < 0.05).The study revealed that arsenic could induce tumor cell apoptosis, by inhibiting p-Akt/GSK-3β, and triggering the Mcl-1-dependent mitochondrial apoptosis pathway.