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The nucleus is considered the ideal target for anti‐tumor therapy because DNA and some enzymes in the nucleus are the main causes of cell canceration and malignant proliferation. However, nuclear target drugs with good biosafety and high efficiency in cancer treatment are rare. Herein, a nuclear‐targeted material MeTPAE with aggregation‐induced emission (AIE) characteristics was developed based on a triphenylamine structure skeleton. MeTPAE can not only interact with histone deacetylases (HDACs) to inhibit cell proliferation but also damage telomere and nucleic acids precisely through photodynamic treatment (PDT). The cocktail strategy of MeTPAE caused obvious cell cycle arrest and showed excellent PDT anti‐tumor activity, which offered new opportunities for the effective treatment of malignant tumors. [ABSTRACT FROM AUTHOR]

Emerging studies have shown that mitochondrial DNA (mtDNA) is an attractive target for anticancer therapeutics. Herein, a heterobimetallic complex [Ru(dip)2(μ‐bpm)PtCl2]Cl2 (RuPt; dip=4,7‐diphenyl‐1,10‐phenanthroline; bpm=2,2′‐bipyrimidine) and the corresponding mononuclear complex [Ru(dip)2(bpm)]Cl2 (Ru) have been designed and synthesized. RuPt can bind to mtDNA and damage it both in the dark and upon visible light irradiation. By using a variety of methods, it was demonstrated that RuPt can interfere with the function of mtDNA by decreasing the amplification and copy number of mtDNA, and affecting the transcriptional level of mitochondria‐encoded genes. Furthermore, RuPt can disturb the physiological processes of mitochondria and induce caspase‐dependent apoptosis in the presence of light. In addition, RuPt shows low systemic toxicity and potent in vivo anticancer potency upon light irradiation. This study provides strong evidence that mtDNA is an important molecular target of RuPt, and photodamaging mtDNA is an effective strategy to overcome cisplatin resistance. Anticancer agent: A ruthenium–platinum heterobimetallic complex has been designed and synthesized as a photodynamic agent to overcome cisplatin resistance. It binds to mitochondrial DNA and can damage it both in the dark and under light irradiation. [ABSTRACT FROM AUTHOR]

A multimodal nanocarrier based on mesoporous silica nanoparticles (MSNs) is developed to co-delivery photosensitizer chlorin e6 (Ce6) and chemotherapeutic agent doxorubicin (Dox) for cancer combination therapy. Ce6 was covalently conjugated with mesoporous silica nanoparticles, which could increase the loading efficiency, and allowed for photodynamic therapy. Doxorubicin was loaded into the pores of mesoporous silica nanoparticles to afford the dual drug delivery system Dox@MSNs-Ce6. These hybrid nanoparticles have an average diameter of about 100 nm and slightly negative charge of about −17 mV. The Dox@MSNs-Ce6 nanoparticles could efficiently enter into cancer cells. The cellular reactive oxygen species level in treated cells increased about 17 times, upon 660 nm light irradiation (10 mW/cm2, 2 min). More importantly, Dox@MSNs-Ce6 exhibited excellent synergistic effect through combining chemotherapy and photodynamic therapy against A549 lung cancer cells. Our work provides an effective strategy for anticancer drug delivery and combination therapy. [ABSTRACT FROM AUTHOR]

Organometallic iridium complexes have emerged as potent anticancer agents in recent years. In this work, three cyclometalated iridium(iii) complexes Ir1–Ir3 containing monodentate five-membered heterocyclic ligands have been synthesized and characterized. Upon visible light (425 nm) irradiation, the five-membered heterocyclic ligands will dissociate from the metal centre. Moreover, Ir1–Ir3 can also act as effective singlet oxygen photosensitizers. Thus, Ir1–Ir3 can exert their light-mediated activation of anticancer effects by dual modes including ligand exchange reactions and generation of singlet oxygen (1O2) upon visible light irradiation. Notably, Ir1 displays a high phototoxicity index of 61.7 against human cancer cells. Further studies show that light-mediated anticancer properties exerted by Ir1–Ir3 occur through reactive oxygen species (ROS) generation, caspase activation, and eventually apoptosis induction. Our study demonstrates that these complexes can act as novel dual-mode light-mediated anticancer agents. [ABSTRACT FROM AUTHOR]

Mitochondria-targeted compounds represent a promising approach to target tumors selectively and overcome resistance to current anticancer therapies. In this work, three cyclometalated iridium(III) complexes ( 1 – 3 ) containing bis- N -heterocyclic carbene (NHC) ligands have been explored as theranostic and photodynamic agents targeting mitochondria. These complexes display rich photophysical properties, which greatly facilitates the study of their intracellular fate. All three complexes are more cytotoxic than cisplatin against the cancer cells screened. 1 – 3 can penetrate into human cervical carcinoma (HeLa) cells quickly and efficiently, and they can carry out theranostic functions by simultaneously inducing and monitoring the morphological changes in mitochondria. Mechanism studies show that these complexes exert their anticancer efficacy by initiating a cascade of events related to mitochondrial dysfunction. Additionally, they display up to 3 orders of magnitude higher cytotoxicity upon irradiation at 365 nm, which is so far the highest photocytotoxic responses reported for iridium complexes. [ABSTRACT FROM AUTHOR]

Ruthenium complexes are promising photosensitizers (PSs), but their clinical applications have many limitations. Here, a multifunctional nano‐platform PDA‐Pt‐CD@RuFc formed by platinum‐decorated and cyclodextrin (CD)‐modified polydopamine (PDA) nanoparticles (NPs) loaded with a ferrocene‐appended ruthenium complex (RuFc) is reported. The NPs can successfully deliver RuFc to the tumor sites. The release of RuFc from the NPs can be triggered by low pH, photothermal heating, and H2O2. The combined photodynamic and photothermal therapy (PDT‐PTT) mediated by PDA‐Pt‐CD@RuFc NPs can overcome the hypoxic environment of tumors from several aspects. First, the platinum NPs can catalyze H2O2 to produce O2. Second, vasodilation caused by photothermal heating can sustain the oxygen supplement. Third, PDT exerted by RuFc can also occur through the non‐oxygen‐dependent Fenton reaction. Due to the presence of PDA, platinum NPs, and RuFc, the nanosystem can be used in multimodal imaging including photothermal, photoacoustic, and computed tomography imaging. The NPs can be excited by the near‐infrared two‐photon light source. Moreover, the combined treatment can improve the tumor microenvironments to obtain an optimized combined therapeutic effect. In summary, this study presents a tumor‐microenvironment‐adaptive strategy to optimize the potential of ruthenium complexes as PSs from multiple aspects. [ABSTRACT FROM AUTHOR]

The alternations in the hypoxic and immune microenvironment are closely related to the therapeutic effect and prognosis of oral squamous cell carcinoma (OSCC). Herein, a new nanocomposite, TiO 2 @Ru@siRNA is constructed from a ruthenium-based photosensitizer (Ru) modified- TiO 2 nanoparticles (NPs) loaded with siRNA of hypoxia-inducible factor-1α (HIF-1α). Under visible light irradiation, TiO 2 @Ru@siRNA can elicit both Type I and Type II photodynamic effects, which causes lysosomal damage, HIF-1α gene silencing, and OSCC cell elimination efficiently. As a consequence of hypoxia relief and pyroptosis induction, TiO 2 @Ru@siRNA reshapes the immune microenvironment by downregulation of key immunosuppressive factors, upregulation of immune cytokines, and activation of CD4+ and CD8+ T lymphocytes. Furthermore, patient-derived xenograft (PDX) and rat oral experimental carcinogenesis models prove that TiO 2 @Ru@siRNA -mediated photodynamic therapy significantly inhibits the tumor growth and progression, and markedly enhances cancer immunity. In all, this study presents an effective hypoxia-adaptive photo-immunotherapeutic nanosystem with great potential for OSCC prevention and treatment. [Display omitted] [ABSTRACT FROM AUTHOR]