Anticancer effect of Euphorbia tirucalli crude extract in cervical cancer cells: Induction of apoptosis, HDAC inhibition, and gene expression modulation

Abstract

Cervical cancer is one of the public health challenges in South Africa caused by infection with human papillomavirus. The need for new, novel, cost-effective therapies that will eradicate cervical cancer are required. This study investigates the anticancer potential of the crude extract of Euphorbia tirucalli in Me180 cells. GC–MS analysis revealed diverse phytochemical profile with potential anticancer activity. Cell viability was assessed using the Alamar Blue, ATP, and LDH assays, respectively. Caspase 3/7 activity was measured using the caspase 3/7 assay. The HDAC cell-based assay was used to measure HDAC reduction. Gene expression of caspase 8, RB1, Bax/Bcl2, RBBP6, CDK2, and CDK4 were assessed using real-time PCR. SOF crude extract treatment resulted in a significant reduction in cell viability. Mechanistic studies at the IC 50 (81.7 μg/ml) demonstrated a decrease in ATP levels, increased caspase 3/7 activity, and increased LDH release, indicating metabolic disruption, induction of apoptosis, and loss of membrane integrity. Epigenetic analysis revealed that the SOF extract significantly inhibited histone deacetylase (HDAC) activity at early time points, suggesting potential HDAC-inhibitory properties. Gene expression analysis showed no detectable expression of caspase 8 or RB1, while the Bax/Bcl2 ratio was upregulated, suggesting activation of the intrinsic apoptotic pathway. RBBP6 and CDK4 were upregulated, and CDK2 was downregulated, reflecting possible modulation of epigenetic and cell cycle regulation. In conclusion, SOF crude extract exhibits significant anticancer activity in Me180 cells through possible induction of intrinsic apoptosis, metabolic disruption, HDAC inhibition, and regulation of key genes involved in epigenetic control and cell cycle progression.