DNA-Binding, Photocleavage, and Photodynamic Anti-cancer Activities of Pyridyl Corroles

The role of corroles in modern cancer therapy: innovation and prospects

Corroles, a class of tetrapyrrolic macrocycles, have garnered significant attention for their potential in cancer therapy due to their unique structural chemistry and ability to coordinate with metals. Their remarkable photophysical properties make them beneficial for photodynamic therapy (PDT) and fluorescence imaging, as they can produce reactive oxygen species when activated by light, offering potential for the treatment of various carcinomas, including hepatic, breast, pancreatic, and lung cancers. Despite the encouraging preclinical and clinical data supporting their therapeutic efficacy, challenges remain in optimizing corrole formulations, particularly concerning targeted delivery, stability, and bioavailability. This review highlights current advancements in corrole-based therapies, focusing on novel nanoparticle formulations that enhance drug distribution and therapeutic efficacy. Furthermore, it examines the mechanisms of corrole-mediated cellular death and the role of photodynamic treatment in inducing apoptosis via various signaling pathways. Additional research is necessary to address formulation-related issues while ensuring the safety and effectiveness of corroles in cancer treatment, therefore maximizing their therapeutic potential and adhering to regulatory standards.

"One-Pot" Synthesized Phosphorus Corrole-Based Metal-Organic Frameworks for Synergistic Phototherapy and Chemodynamic Therapy

As a distinctive class of porphyrin derivatives, corroles offer exceptional potential in phototherapy applications owing to their unique electronic structures. However, developing metal-organic frameworks (MOFs) that incorporate photosensitive corroles as functional ligands for synergistic phototherapy remains a formidable challenge. Herein, for the first time, the unique phosphorus corrole-based MOFs Cor(P)-Hf with (3,18)-connected gea topology are reported, which are constructed by Cs-symmetric dicarboxylate 3-connected linkers, 10-pentafluorophenyl-5,15-di(p-benzoate)phosphorus corrole (Cor(P)), and the peculiar D3h-symmetric 18-connected Hf12-oxo clusters. Interestingly, six para-position F substituents of six Cor(P) linkers are found to be coordinated with the apex of the Hf12-oxo cluster through Hf-F bonds along the c-axis direction, which is believed to help stabilize the framework. Furthermore, the mixed corrolic ligand-based MOFs Cor(P)/Cor(Cu)-Hf and Cor(P)/Cor(Fe)-Hf involving Cor(Fe) or Cor(Cu) as the secondary functional linkers are constructed by a simple "one-pot" solvent-thermal method, respectively. Remarkably, Cor(P)/Cor(Fe)-Hf facilitates synergistic phototherapy combining photodynamic therapy (PDT), photothermal therapy (PTT), and chemodynamic therapy (CDT) when activated by an 808 nm laser, as evidenced by in vivo and in vitro experiments. This study demonstrates corrole-based MOFs Cor(P)-Hf as a powerful multifunctional nanoplatform for anti-cancer phototherapy.

First report of trans-A2B-corrole derived from a lapachone derivative: photophysical, TD-DFT and photobiological assays

In this work, the synthesis, characterization and photophysical assays of a new trans-A₂B-corrole derivative from the naturally occurring quinone are described. β-Lapachone is a naturally occurring quinoidal compound that provides highly fluorescent heterocyclic compounds such as lapimidazoles. The new trans-A₂B-corrole compound was obtained from the reaction between 2,3,4,5,6-(pentafluorophenyl)dipyrromethane and the lapimidazole bearing an aldehyde group. The dyad was characterized by high-resolution mass spectrometry (HRMS), NMR spectroscopy (¹H, COSY 2D, HMBC, ¹⁹F), FT-IR, UV-vis, steady-state and time-resolved fluorescence, electrochemical studies (CV), TD-DFT analysis and photobiological experiments, in which includes aggregation, stability in solution, photostability and partition coefficients assays. Finally, ROS generation assays were performed using 1,3-diphenylisobenzofuran (DPBF) method and the presented compound showed significant photostability and singlet oxygen production.

Gallium(III) Amide Corroles: DNA Interaction and Photodynamic Activity in Cancer Cells

A series of gallium(III) amide corroles including meso-5,15-bis(pentafluorophenyl)-10-(4-Pyridinamide-phenyl)corrole gallium (III) (1-Ga), meso-5,15-bis(pentafluorophenyl)-10-(4-Furamide-phenyl)corrole gallium(III) (2-Ga) and meso-5,15-bis(pentafluorophenyl)-10-(4-Thiophenamide-phenyl)corrole gallium(III) (3-Ga) were synthesized. The interaction of these complexes with DNA and their photodynamic antitumor activities have been studied. UV spectra titration showed that these gallium(III) corroles interact with calf thymus DNA (CT-DNA) through an external binding mode. All three gallium(III) corroles can effectively generate singlet oxygen under illumination and have good photostability. Among the three gallium(III) corroles, 2-Ga exhibited excellent photodynamic antitumor activity against the tested tumor cell lines under light irradiation (625±2 nm, 0.3 mW/cm2 , 1.08 J/cm2 ). The best phototoxicity was observed by 2-Ga against HepG2 cells (IC50 =6.3±0.9), which is even better than temoporfin (IC50 =8.4±1.8). It could block HepG2 cells in the sub-G0 phase and effectively induce apoptosis of HepG2 cells under 625 nm light irradiation.

Corroles at work: a small macrocycle for great applications

Corrole chemistry has witnessed an impressive boost in studies in the last 20 years, thanks to the possibility of preparing corrole derivatives by simple synthetic procedures. The investigation of a large number of corroles has highlighted some peculiar characteristics of these macrocycles, having features different from those of the parent porphyrins. With this progress in the elucidation of corrole properties, attention has been focused on the potential for the exploitation of corrole derivatives in different important application fields. In some areas, the potential of corroles has been studied in certain detail, for example, the use of corrole metal complexes as electrocatalysts for energy conversion. In some other areas, the field is still in its infancy, such as in the exploitation of corroles in solar cells. Herein, we report an overview of the different applications of corroles, focusing on the studies reported in the last five years.

Fluorescent pyrene moiety in fluorinated C6F5-corroles increases the interaction with HSA and CT-DNA

Two fluorinated meso-C6F5-corroles (5,15-bis(pentafluorophenyl)-10-(phenyl)corrole and 5,15-bis(pentafluorophenyl)-10-(1-pyrenyl)corrole) were biologically evaluated in terms of binding affinity to human serum albumin (HSA) and calf-thymus DNA (CT-DNA) via multiple spectroscopic techniques under physiological conditions combined with molecular docking calculations. The HSA:corrole interaction is spontaneous and moderate via static binding, disturbing both secondary and tertiary albumin structures at high fluorinated corrole concentrations. The competitive binding studies indicated positive cooperativity or allosteric activation, while molecular docking calculations suggested that both fluorinated corroles bind preferentially inside subdomains IIA and IB (sites I and III, respectively). The experimental CT-DNA binding assays indicated that fluorinated corroles interact spontaneously by non-classical modes in the minor groove of the CT-DNA strands via static fluorescence quenching mechanism. Molecular docking results also showed the minor groove as the main binding site for CT-DNA. Overall, the pyrene moiety increased the interaction with HSA and CT-DNA, which is probably due to the planarity and volume that favors the pyrene unit to be buried inside the biomacromolecule pockets.

Underlying mechanism of the photodynamic activity of hematoporphyrin‑induced apoptosis in U87 glioma cells

Photodynamic therapy (PDT) is a relatively novel type of tumor therapy method with low toxicity and limited side‑effects. The aim of the present study was to investigate the underlying mechanism and potential microRNAs (miRNAs) involved in the treatment of glioma by PDT with hematoporphyrin, a clinical photosensitizer. The photodynamic activity of hematoporphyrin on the cell viability and apoptosis of gliomas was investigated by MTT, and flow cytometry and fluorescence microscopy, respectively. Alterations in singlet oxygen and mitochondrial membrane potential were detected. The differentially expressed miRNAs and proteins were evaluated by miRNA gene chip and apoptosis‑associated protein chip, respectively. The results demonstrated that cell viability significantly decreased with hematoporphyrin concentration. PDT with hematoporphyrin significantly increased cell apoptosis at a later stage, induced the content of reactive oxygen species (ROS) and decreased the mitochondrial membrane potential, indicating that PDT with hematoporphyrin inhibited cell growth via induction of radical oxygen, decreased the mitochondrial membrane potential and induced apoptosis. The upregulated miRNAs, including hsa‑miR‑7641, hsa‑miR‑9500, hsa‑miR‑4459, hsa‑miR‑21‑5p, hsa‑miR‑663a and hsa‑miR‑205‑5p may be important in PDT‑induced cell apoptosis in glioma. Transporter 1, ATP binding cassette subfamily B member‑ and nuclear factor‑κB‑mediated apoptosis signaling pathways were the most significant pathways. Thus, the current study presents PDT as a potential therapeutic approach for the treatment of malignant glioma, and identified miRNAs for the molecular design and development of a third‑generation photosensitizer (PS).

Synthesis, characterization and in vitro and in vivo photodynamic activities of a gallium(iii) tris(ethoxycarbonyl)corrole

A gallium(iii) tris(ethoxycarbonyl)corrole is a highly effective photosensitizer against A549 cancer cells via p38 MAPK signaling cascade pathways.