Thermal cycling as a novel thermal therapy to synergistically enhance the anticancer effect of propolis on PANC‑1 cells

Abstract

Hyperthermia (HT) has shown potential in cancer therapy. In particular, it appears to sensitize cancer cells to chemotherapy. However, a major concern associated with HT is that the thermal dosage applied to the tumor cells may also harm the normal tissue cells. Besides, the drugs used in HT are conventional chemotherapy drugs, which may cause serious side effects. The present study demonstrated a novel methodology in HT therapy called thermal cycle (TC)-HT. With this strategy, a therapeutic window with a maximum synergistic effect was created by combining TC-HT with natural compounds, with minimal unwanted cell damage. The natural compound propolis was selected, and the synergistic anticancer effect of TC-HT and propolis was investigated in pancreatic cancer cells. The present results demonstrated for the first time that TC-HT could enhance the anticancer effect of propolis on PANC-1 cancer cells through the mitochondria-dependent apoptosis pathway and cell cycle arrest. Combined treatment greatly suppressed mitochondrial membrane potential, which is an important indicator of damaged and dysfunctional mitochondria. Furthermore, the cell cycle-regulating protein cell division cycle protein 2 was downregulated upon combined treatment, which prevented cellular progression into mitosis. The present study offers the first report, to the best of our knowledge, on the combination of TC-HT with a natural compound for pancreatic cancer treatment. It is anticipated that this methodology may be a starting point for more sophisticated cancer treatments and may thereby improve the quality of life of many patients with cancer.

Modulated Electro-Hyperthermia Resolves Radioresistance of Panc1 Pancreas Adenocarcinoma and Promotes DNA Damage and Apoptosis In Vitro

“…One group showed that both extrinsic (hot air and water bath), or iron oxide nanoparticle based magnetic hyperthermia can damage collagen architecture in hetero-spheroids of Panc1 cells and WI-38 fibroblasts leading to cell death, but without specifying the contribution of Panc1 to this [ 51 ]. Another study demonstrated mitochondrial-driven apoptosis of Panc1 tumor cells after using PCR thermal cycling-based heating to 44 °C, which, however, was well above the conventional 42 °C therapeutic temperature [ 52 ]. In our present study, mEHT monotherapy at 42 °C and mEHT in combination with radiotherapy provoked a significantly elevated apoptosis.…”

Scanning acoustic microscopy imaging of cellular structural and mechanical alterations from external stimuli

“…The heat generated by microwave also induced protein aggregation [ 30 ]. Hyperthermia used for anticancer therapy operates on similar principles [ 32 ]. The findings demonstrate how SAM can measure and evaluate heat-induced cell damage.…”

Potential of Polymeric Films Loaded with Gold Nanorods for Local Hyperthermia Applications

“…On the other hand, GnRs-loaded films showed a significant increase in temperature. To achieve local hyperthermia, and therefore a biological response of cell death or regeneration, heating cycles may be needed in order to maintain a temperature over 43 • C for a period of time [42,43]. Therefore, irradiation of polymeric films was conducted for 3 cycles of 10 s each, followed by cooling until room temperature, and thermal images were taken before and after this to calculate the increase in temperature.…”