Metal Complexes for Cancer Sonodynamic Therapy

Abstract

Sonodynamic therapy (SDT) for cancer treatment is gaining attention owing to its non‐invasive property and ultrasound‘s (US) deep tissue penetration ability. In SDT, US activates the sonosensitizer at the target deep‐seated tumors to generate reactive oxygen species (ROS), which ultimately damage tumors. However, drawbacks such as insufficient ROS production, aggregation of sonosensitizer, off‐target side effects, etc., of the current organic/nanomaterial‐based sonosensitizers limit the effectiveness of cancer SDT. Very recently, metal complexes with tunable physiochemical properties (such as sonostability, HOMO to LUMO energy gap, ROS generation ability, aqueous solubility, emission, etc.) have been devised as effective sonosensitizers, which could overcome the limitations of organic/nanomaterial‐based sonosensitizers. This concept introduces all the reported metal‐based sonosensitizers and delineates the prospects of metal complexes in cancer sonodynamic therapy. This new concept of metal‐based sonosensitizer can deliver next‐generation cancer drugs.

Transition Metal Complexes as Antimalarial Agents: A Review

“…The development of carbon monoxide-releasing molecules (CORMs) has emerged as an alternative transporter of CO. [152][153][154] The release of CO can be provoked by an external trigger such as light, ultrasound, and enzymes etc. [155][156][157] CO prevents hemoglobin from breaking down into free hemoglobin which ultimately stops the formation of hemozoin. In this regard, Smith and co-workers explored the antimalarial activity of quinoline-triazole scaffolds with tricarbonyl manganese (Mn) CORMs (86, 87) as depicted in (Figure 21).…”

“…The development of carbon monoxide‐releasing molecules (CORMs) has emerged as an alternative transporter of CO [152–154] . The release of CO can be provoked by an external trigger such as light, ultrasound, and enzymes etc [155–157] . CO prevents hemoglobin from breaking down into free hemoglobin which ultimately stops the formation of hemozoin.…”

Grand challenges in bioinorganic chemistry

“…• to overcome the resistance of solid or hypoxic tumours by promoting less oxygen-dependent mechanisms (e.g., T 1 and S 1 activation, Photoactivated Chemotherapy (PACT)); • to advance selectivity via the addition of biological tags or conjugated antibodies (Gomez et al, 2020) that target tumour tissue or certain subcellular organelles (e.g., mitochondria which are associated with tumorigenesis and tumour progression and susceptible to oxidative stress); • to reduce dark toxicity e.g., via encapsulation (Villemin et al, 2019); • to advance the development of theranostic agents (Vaidya et al, 2022) and sonodynamic therapies (Mandal et al, 2022).…”

A high performance AIE-active sonosensitizer for efficient sonodynamic tumor therapy

“…Although PDT has been demonstrated as a promising alternative treatment for various cancers in both fundamental research and the clinic, the inherent drawbacks of poor penetration restrict its application in relatively small and superficial tumor treatment. 11,12 Sonodynamic therapy (SDT), first explored in the 1990s by Umemura and other researchers, utilizes low intensity ultrasound (US) to generate ROS based on sonosensitizers, and has been highlighted as a high potential therapeutic modality. [13][14][15] Based on the intrinsic property of US with negligible attenuation in tissues, SDT presents a high penetration depth of up to several tens of centimeters, which permits the efficient therapeutic effect towards deep-seated and large solid tumors with minimal damage to surrounding normal tissues.…”

“…Although PDT has been demonstrated as a promising alternative treatment for various cancers in both fundamental research and the clinic, the inherent drawbacks of poor penetration restrict its application in relatively small and superficial tumor treatment. 11,12…”