Conjugation of Hypericin to Gold Nanoparticles for Enhancement of Photodynamic Therapy in MCF-7 Breast Cancer Cells

Abstract

Breast cancer, among the different types of cancer, is one of the most diagnosed cancers and the leading cause of mortalities amongst women. Factors, including genetic and epigenetic alterations in tumors, make it resistant to therapies, which results in treatment failures and/or recurrence. Furthermore, the existing therapies have many unfavorable side effects leading to poor prognosis and reduced therapeutic outcomes. Photodynamic therapy (PDT) is one of the most effective cancer therapies with increased selectivity and specificity toward cancer cells. As a result, the use of gold nanoparticles (AuNP) further improves the effectiveness of PDT by increasing the drug loading capacity into the cells. In this study, hypericin (Hyp) photosensitizer (PS) was adsorbed on gold nanoparticles (AuNPs) by sonication to achieve physical adsorption of the PS to AuNP. The resulting compound was characterized by FTIR, Zeta potential, UV-Vis spectroscopy, and TEM. The compound was used for the PDT treatment of MCF-7 human breast cancer in vitro. Cellular responses at 12 h post-PDT at 10 J/cm2 were observed. Cellular morphology, LDH membrane integrity, ATP luminescence assay, and Annexin V/PI staining were performed. The results demonstrated typical cell death morphological features while the biochemical responses indicated increased LDH and decreased ATP levels. In conclusion, this study presents an insight into the application of advanced PDT in breast cancer cells by inducing cancer cell death in vitro via apoptosis.

Overcoming challenges in cancer treatment: Nano‐enabled photodynamic therapy as a viable solution

“…Apoptotic cell death is linked to direct cell injury when the PS is found in the mitochondria and results in Bcl‐2 damage and Cyt c release (Peng et al, 2022). “One or both of the two primary apoptotic pathways—the Bcl‐2 family of proteins controls the intrinsic pathway and the death domains protein of tumor necrosis factor receptors (TNF‐R) controls the extrinsic pathway—are mediated by caspases” when NE‐PDT is used to induce apoptosis in mammalian cells (Mokoena et al, 2022). Apoptotic genes like Death receptor 5 (DR5), the Fas cell surface death receptor (Fas), and the p53 apoptotic trigger linked to PMP22 start the extrinsic apoptotic pathway (PERP; Merlin, Dellaire, et al, 2021).…”

“…Quantum dots exhibit unique optical properties for targeted imaging and therapeutic purposes (Han et al, 2019). AUNPs enhance light absorption, improving PDT efficacy (Mokoena et al, 2022). Silica NPs facilitate drug delivery and can be modified for specific targeting, ensuring precise treatment (Sivamaruthi et al, 2023).…”

Nano‐phototherapy: Favorable prospects for cancer treatment

“…This could enable greater subcellular accumulation (Mkhobongo et al, 2022). Sonication was used to physically adsorb hypericin onto AuNPs, creating a non‐covalent molecule that enhanced the accumulation of drug in MCF‐7 cells to raise the PDT effectiveness between the lower and higher doses (Mokoena et al, 2022).…”

Recent Progress of Gold-Based Nanostructures towards Future Emblem of Photo-Triggered Cancer Theranostics: A Special Focus on Combinatorial Phototherapies

“…The non-covalent bonds between the AuNPs and Hyp increase the PS accumulation in MCF-7 breast cancer cells and hence improve PDT efficiency with the minimum concentrations. From this study, it is revealed that physically loaded Hyp PS on AuNPs is a hopeful strategy for hydrophobic PS drug delivery to improve PDT efficiency [ 116 ]. The recent studies involving PS-conjugated AuNPs for PDT against cancer using in vitro models are listed in Table 4 .…”