Axisymmetric bis-tridentate Ir(iii) photoredox catalysts for anticancer phototherapy under hypoxia

Abstract

Hypoxia and drug resistance of tumor cells remain one of the major problems in clinical anticancer therapy. The in-cell photo-redox catalysis may combat these problems. Herein, we reported the novel...

Ir(III) Compounds Containing a Terdentate Ligand Are Potent Inhibitors of Proliferation and Effective Antimetastatic Agents in Aggressive Triple-Negative Breast Cancer Cells

“…Recently, cationic heteroleptic bis-cyclometalated Ir­(III) complexes have received enormous attention due to their excellent anticancer activity with non-conventional modes of action and precise subcellular localization. − However, most complexes with bidentate ligands often exist as a mixture of enantiomers, which may bring unanticipated side effects. The incorporation of tridentate ligands can avoid chirality, as in the cases of recently reported iridium photocatalysts of the types [Ir­(N^N^N)­(C^N)­Cl] + , [Ir­(N^N^N)­(C^N^C)] + , [Ir­(N^N^N) 2 ] 3+ , and [Ir­(N^N^N))­(C^N))­Cl] 2 2+ . − …”

Exploring the phototoxicity of GSH-resistant 2-(5,6-dichloro-1H-benzo[d]imidazol-2-yl)quinoline-based Ir(iii)-PTA complexes in MDA-MB-231 cancer cells

“…4,5 It is noteworthy that several Ir-based photosensitizers have been developed recently for photoactivated cancer therapy. [6][7][8][9][10] Iridium complexes are attracting increasing attention in photocatalytic cancer therapy because of their remarkable photostability, flexible structure and redox potential, various photosensitization mechanisms, and remarkably long excited-state lifetimes. [11][12][13][14][15][16][17] To investigate the phototoxic effects of hypoxia-active Ir(III)-based scaffolds on 3D tumor spheroids, B. Elias and colleagues conducted research in this regard.…”

Green Light-Triggered Photocatalytic Anticancer Activity of Terpyridine-Based Ru(II) Photocatalysts

“…This indicates that molecular O 2 is involved in the catalytic process, like the Ir(III) photocatalysts reported in the literature. [10][11][12]21 O 2 is probably involved in the regeneration of the Ru(II) active catalyst. 13−15 Cellular Uptake.…”

“…10 M deaths in 2020) and it is badly affecting the global health index . Primarily, Pt-based anticancer drugs have been employed as chemotherapeutics in combating this disease. − However, their low tumor selectivity, adverse side effects, and acquired drug resistance have led to new initiatives toward developing better chemotherapeutic agents and advanced cancer therapies with reduced side effects, better tumor selectivity, and enhanced cytotoxicity. , Recently, a new type of photoactivated cancer therapy termed “photocatalytic cancer therapy” has arisen as a potential non-invasive alternative to the current cancer therapies. − In photocatalytic cancer therapy, a photosensitive drug molecule is exposed to a certain wavelength of light to induce cytotoxicity via in-cell catalytic reactions and the production of reactive oxygen species (ROS). − The in-cell catalytic reactions (such as NADH/NAD­(P)­H oxidation) and ROS generation are ultimately reported to perturb energy metabolism and redox state in cancer cells selectively. , These further disrupt cell signaling cascades and/or modify gene expression regulation, ultimately causing tumor cell damage. − This novel concept, photocatalytic cancer therapy, has shown promising results in overcoming cisplatin resistance with high tumor selectivity both in vivo and in vitro . The advantages of photocatalytic cancer drug development could be (i) low to extremely low drug dose, helpful to avoid the toxicity of metal (in the case of metal-based photocatalytic anticancer agents), (ii) selective activation of the drug at the specified tumor site, helpful to reduce drug’s side effects, and (iii) overcoming current drug resistance issues by multifunctional and multitargeting anticancer mechanism. , …”