Halofantrine Upregulates ATP6V0D2 and Induces Cytotoxic Autophagy in GBM Models

Halofantrine (halo) is an antimalarial drug that has recently been proven to have the potential to treat Glioblastoma (GBM).

The aim of the study is to explore the inhibitory effect of halos on GBM and its mechanism.

The expression of ATP6V0D2 in GBM was analyzed using the Cancer Genome Atlas (TCGA), the comprehensive database of gene expression, and clinical patient samples. In vitro, we evaluated the inhibitory effect of halo on U251 cells; qPCR, Western blot, and immunofluorescence were used to detect the changes in ATP6V0D2 and autophagy-related genes and proteins. Transmission electron microscopy was used to detect the formation of autophagosomes. A stable ATP6V0D2 knockdown and overexpression model was constructed in U251 cells to verify the criticality of ATP6V0D2. The in vivo anti-tumor effect and mechanism of halo were evaluated using a U251 cell axillary tumor-bearing mouse model (independent experiment repeat number (n = 5) and tail vein administration injection.

The expression level of ATP6V0D2 is relatively low in GBM patients. Halo upregulates ATP6V0D2 and induces cytotoxic autophagy (TA) in U251. Knockdown of ATP6V0D2 can inhibit halo-mediated TA and cytotoxicity, while overexpression can enhance these effects. Halo also demonstrated significant anti-GBM activity in vivo, and its mechanism was consistent with the results of in vitro studies.

This study has preliminarily demonstrated that the anti-malarial drug halo can promote autophagy in GBM cells by upregulating the ATP6V0D2 gene, thereby exerting an anti-GBM effect. So far, no experimental studies have been conducted on the permeability of the blood-brain barrier within the halo body. Furthermore, the potential cardiac toxicity of halo is a point that deserves particular attention.

Halo triggers cytotoxic autophagy in U251 cells by upregulating ATP6V0D2, establishing the key tumor suppressor factor status of ATP6V0D2 in GBM.