Glioma constitutes a primary brain tumor with a poor prognosis and survival. The accruing concerns of side effects accompanying the conventional treatment options and chances of tumor relapse have impelled a paradigm shift towards green chemistry for discovering and implementing effective, non-toxic attributes of plant-based products in the medicinal field. We have previously achieved partial rescue of the brain tumor in a Drosophila brain tumor mutant, lethal (2) giant larvae [l(2)gl], using artemisinin and curcumin. In this study, we investigate a key artemisinin derivative, dihydroartemisinin (DHA), using in vitro and in vivo glioma models.

In vitro drug screening was performed using cell viability, cell cycle analysis, flow cytometry-based apoptosis assay, and immunoblotting to examine the key pathways involved. Subcutaneous and orthotopic murine glioma models were developed, and DHA dosage for administration was standardized. The physiological and behavioral parameters of the animals were monitored, and an in vivo serum biochemical assay was conducted. The extracted samples were subjected to hematoxylin and eosin staining, western blotting, and immunostaining. The findings were compared between the control and the treatment groups.

DHA lowered the proliferation of glioma cells, induced cell cycle arrest at the G0/G1 and G2/M checkpoints in a dose-dependent manner, and promoted apoptosis in vitro. It targeted the Ak strain transforming (AKT) signaling axis by eliciting phospho-AKT (pAKT) inhibition and also induced caspase-3 dependent apoptosis, leading to an effective tumor regression in the subcutaneous flank rat glioma model. The drug delayed tumor invasiveness in the orthotopic glioma models of rat and athymic mice, thus mitigating the disease severity and the associated symptoms. Immunohistochemical analysis in tumors using angiogenesis and proliferation markers showed reduced angiogenesis and proliferative rate post-treatment.

Our work unveils the therapeutic potential of DHA in modulating glioma progression both in vitro and in vivo. By reprogramming the tumor growth dynamics and targeting key signaling networks involving AKT and caspase-3, DHA may pose as a promising therapeutic candidate for glioma treatment.