Combinatorial Anticancer Effects of The Non-Invasive High Voltage micro-second Pulse Electric Field with Low-Dose Curcumin on A549 Cells

Abstract

Purpose Novel, alternative and combinatorial approaches to combat cancers with minimal side effects is the need of the hour, owing to significant therapy-associated adverse effects. Natural molecule curcumin has shown to have significant anticancer action in lung cancers, a major cause of mortality world over. However, usage of curcumin is limited by its poor bioavailability. High voltage microsecond pulse electric field (HV-µsPEF) therapy is an emerging alternative option in cancer therapy which can be used as an effective adjuvant anti-cancer therapy. In the current investigation, we assessed the combinatorial effect of HV-µsPEF with low-dose curcumin on A549 lung cancer cell line with the main objective of minimization of the curcumin dose required for its anti-cancer action. Method HV-µsPEF was generated using a previously reported pulse-generator which was combined with low doses of curcumin to assess effects on A549 cell line. Phase-contrast microscopy based cellular morphology analysis, flow-cytometry based analyses to assess the mode of cell death, uptake of curcumin, assessment of reactive oxygen species and that of mitochondrial membrane potential (MMP) loss were carried out. Results Our work demonstrates a highly synergistic cell death induction in A549 cells as assessed by phase contrast microscopy and flow-cytometry based analysis due to the increased uptake of curcumin by cancer cells in the presence of HV-µsPEF. This led to increased ROS production and loss of MMP in cancer cells with the combinatorial treatment. Conclusion This study shows promising anti-cancer effects in the usage of low doses of curcumin, a natural molecule, with HV-µsPEF. Combined treatment of HV-µsPEF with curcumin in A549 cells increased the uptake of curcumin in the cells leading to effective induction of cell death via increased ROS production and MMP loss effectively minimizing the requirement of high doses of curcumin which are practically not achievable.