Identification of the molecular target(s) of anticancer metal complexes is a formidable challenge since most of them are unstable toward ligand exchange reaction(s) or biological reduction under physiological conditions. Gold(III) meso-tetraphenylporphyrin (gold-1 a) is notable for its high stability in biological milieux and potent in vitro and in vivo anticancer activities. Herein, extensive chemical biology approaches employing photo-affinity labeling, click chemistry, chemical proteomics, cellular thermal shift, saturation-transfer difference NMR, protein fluorescence quenching, and protein chaperone assays were used to provide compelling evidence that heat-shock protein 60 (Hsp60), a mitochondrial chaperone and potential anticancer target, is a direct target of gold-1 a in vitro and in cells. Structure-activity studies with a panel of non-porphyrin gold(III) complexes and other metalloporphyrins revealed that Hsp60 inhibition is specifically dependent on both the gold(III) ion and the porphyrin ligand.

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Amphiphilic gold(iii) porphyrin–PEG conjugates can undergo self-assembly into nanostructures, resulting in promising anti-cancer properties with minimal systemic toxicity. The nanostructures can be employed as nanocarriers for drug co-delivery.

Luminescent iridium(iii) porphyrin NHC complexes are efficient singlet oxygen generators and antitumor agents.

The use of gold in medicine has a long history. Recent clinical applications include anti-inflammatory agents for the treatment of rheumatoid arthritis (chrysotherapy), and is currently being developed as potential anticancer chemotherapeutics. Gold(III), being isoelectronic to platinum(II) as in cisplatin, is of great interest but it is inherently unstable and redox-reactive under physiological conditions. Coordination ligands containing C and/or N donor atom(s) such as porphyrin, pincer-type cyclometalated and/or N-heterocyclic carbene (NHC) can be employed to stabilize gold(III) ion for the preparation of anticancer active compounds. In this review, we described our recent work on the anticancer properties of gold(III) compounds and the identification of molecular targets involved in the mechanisms of action. We also summarized the chemical formulation strategies that have been adopted for the delivery of cytotoxic gold compounds, and for ameliorating the in vivo toxicity.

Identification of the molecular target(s) of anticancer metal complexes is aformidable challenge since most of them are unstable towardl igand exchange reaction(s) or biological reduction under physiological conditions.Gold(III) meso-tetraphenylporphyrin (gold-1 a)i sn otable for its high stability in biological milieux and potent in vitro and in vivo anticancer activities.H erein, extensive chemical biology approaches employing photo-affinity labeling,click chemistry, chemical proteomics,cellular thermal shift, saturation-transfer difference NMR, protein fluorescence quenching, and protein chaperone assays were used to provide compelling evidence that heat-shockprotein 60 (Hsp60), amitochondrial chaperone and potential anticancer target, is ad irect target of gold-1 a in vitro and in cells.S tructure-activity studies with ap anel of non-porphyrin gold(III) complexes and other metalloporphyrins revealed that Hsp60 inhibition is specifically dependent on both the gold(III) ion and the porphyrin ligand.

Vimentin is a cytoskeletal intermediate filament protein that plays pivotal roles in tumor initiation, progression, and metastasis, and its overexpression in aggressive cancers predicted poor prognosis. Herein described is a highly effective antitumor and antimetastatic metal complex [PtII(C^N^N)(NHC2Bu)]PF6 (Pt1a; HC^N^N = 6-phenyl-2,2′-bipyridine; NHC= N-heterocyclic carbene) that engages vimentin via noncovalent binding interactions with a distinct orthogonal structural scaffold. Pt1a displays vimentin-binding affinity with a dissociation constant of 1.06 µM from surface plasmon resonance measurements and fits into a pocket between the coiled coils of the rod domain of vimentin with multiple hydrophobic interactions. It engages vimentin in cellulo, disrupts vimentin cytoskeleton, reduces vimentin expression in tumors, suppresses xenograft growth and metastasis in different mouse models, and is well tolerated, attributable to biotransformation to less toxic and renal-clearable platinum(II) species. Our studies uncovered the practical therapeutic potential of platinum(II)‒NHC complexes as effective targeted chemotherapy for combating metastatic and cisplatin-resistant cancers.

Self-assembly of platinum(ii) glycosylated arylacetylide gave transformable superstructures upon enzymatic action in cellulo, leading to perturbation of an autophagy-lysosomal system and cancer cell death.