Potentiating the Cytotoxic Activity of a Novel Simvastatin-Loaded Cubosome against Breast Cancer Cells: Insights on Dual Cell Death via Ferroptosis and Apoptosis

Abstract

Purpose Female breast cancer is the most prevalent cancer worldwide. Emerging evidence shows that simvastatin (SIM) has promising anticancer activities. However, the underlying mechanisms are not fully elucidated. Increasing reports imply statins can modulate ferroptosis through disrupting reactive oxygen species (ROS) and glutathione peroxidase enzyme (GPX4) levels. However, whether ferroptosis contributes to SIM anticancer activity, especially regarding GPX4 is unclear. Moreover, poor aqueous SIM solubility hinders its delivery in adequate levels to tumor sites. Meanwhile, cubosomes are biocompatible nanocarriers that enhance lipophilic drug delivery. Therefore, in this study, we formulated a novel SIM-loaded cubosome (SIM-CB) and analyzed its cytotoxic activity on MCF-7 cancer cells in comparison with free SIM. Methods The present study tested the cytotoxic activity of SIM-CB on MCF-7 cells, in comparison with SIM using sulphorhodamine assay. We analyzed SIM-CB effect on apoptosis and cell cycle using flowcytometry, and investigated its effect on Bcl-2, caspase 3, ROS, reduced glutathione (GSH), lipid peroxides and GPX4 enzyme. Finally, we tested the persistence of SIM-CB apoptosis and ferroptosis activities on MCF-7 cells in presence of vitamin E, a potent antioxidant and ferroptosis inhibitor. Results SIM-CB was successfully formulated at the nano size. SIM-CB significantly increased simvastatin therapeutic activity, with IC 50 of SIM-CB 52% lower than SIM. 95% CI [1.8, 2.7], SD = 0.34 for SIM-CB, and [4.1, 5.2], SD = 0.45 for SIM. Compared with free SIM, SIM-CB doubled total deaths and increased apoptosis (p < 0.05). Moreover, SIM-CB remarkably increased caspase-3, ROS, and lipid peroxide levels but decreased antiapoptotic Bcl-2 protein, GSH, and GPX4 compared with free SIM. Notably, SIM-CB elicited a high distinguished resistance against the inhibitory effects of vitamin E. Conclusion To the best of our knowledge, this study is the first to present SIM-CB as a promising means to enhancing the therapeutic potential of simvastatin against breast cancer cells, through potentiating both apoptosis and ferroptosis.

Effect of Pravastatin and Simvastatin on the Reduction of Cytochrome C

“…Decreased glutathione and increased reactive oxygen species (ROS) levels were observed. Due to the increased ROS level, the concentration of glutathione may be decreased by glutathione peroxidase, but significantly decreased glutathione peroxidase 4 levels have been observed [ 25 ]. This discrepancy can be resolved by our observation that free cytochrome c can decrease reduced glutathione concentration independently of peroxidase.…”

Formulation, Characterization, and Evaluation of Doxorubicin-loaded Cubosome as a Cytotoxic Potentiator against HCT-116 Colorectal Cancer Cells

“…11 Since cubosomes viscosity is low and there mostly are in suspension, it makes it easier to deliver drugs to targeted sites. [12][13] As cubosomes have been proven to be an efficient drug delivery system and have been utilized to deliver anticancer medications, [14][15] we formulated a DOXloaded cubosome nanoparticle (DOX-CB) stabilized by Pluronic F127 aimed to enhance the therapeutic window and maximize the anticancer effect of DOX. The formulated DOX-CB was characterized using UV-Spectroscopy, FTIR, XRD, DLS, TEM, and FESEM with EDAX, and DOX-CB was used on CRC cell line -HCT 116 and tested for cytotoxicity, Nitric oxide, and Reactive oxygen species.…”

Simvastatin in the Treatment of Colorectal Cancer: A Review

“…Statins are commonly used drugs to treat hyperlipidemia and prevent cardiovascular diseases. In recent years, relevant studies have pointed out that statins have good therapeutic effects on a variety of diseases, including cancer, through their involvement in angiogenesis, proliferation, apoptosis, and metastasis pathways [ 12 , 13 ]. Furthermore, studies have shown that among statins, simvastatin, which has high lipophilicity, shows a beneficial anticancer activity in colon cancer cell lines.…”

“…Statins are commonly used drugs to treat hyperlipidemia and prevent cardiovascular diseases. In recent years, relevant studies have pointed out that statins have good therapeutic e ects on a variety of diseases, including cancer, through their involvement in angiogenesis, proliferation, apoptosis, and metastasis pathways [12,13].…”