Gemini cationic surfactant of 1, 3-bis (dodecyl dimethyl ammonium chloride) propane as a novel excellent inhibitor for the corrosion of cold rolled steel in HCl solution.

Gemini surfactants have become the research focus of novel excellent inhibitors because of their special structure (two amphiphilic moieties covalently connected at head group by a spacer) and excellent surface properties. It is proved by theoretical calculations that 1, 3-bis (dodecyl dimethyl ammonium chloride) propane (BDDACP) molecules can perform electron transfer with Fe (110). And it has a small fraction free volume, thus greatly reducing the diffusion and migration degree of corrosive particles. The potentiodynamic polarization curve showed that coefficients of cathodic and anodic reaction less than 1 and polarization resistance increased to 1602.9 Ω cm-2 after added BDDACP, confirming that BDDACP significantly inhibited the corrosion reaction by occupying the active site. The electrochemical impedance spectrum of imperfect semi-circle shows that the system resistance increases and double layer capacitance after added BDDACP. Weight loss tests also confirmed that BDDACP forms protective film by occupying the active sites on steel surface, and the maximum inhibition efficiency is 92 %. Comparison of the microscopic morphology showed that steel surface roughness was significantly reduced after added BDDACP. The results of time-of-flight secondary ion mass spectrometry show that steel surface contains some elements from BDDACP, which confirms the adsorption of BDDACP on steel surface.

A platinum(IV)-artesunate complex triggers ferroptosis by boosting cytoplasmic and mitochondrial lipid peroxidation to enhance tumor immunotherapy.

Ferroptosis is an iron-dependent cell death form that initiates lipid peroxidation (LPO) in tumors. In recent years, there has been growing interest on ferroptosis, but how to propel it forward translational medicine remains in mist. Although experimental ferroptosis inducers such as RSL3 and erastin have demonstrated bioactivity in vitro, the poor antitumor outcome in animal model limits their development. In this study, we reveal a novel ferroptosis inducer, oxaliplatin-artesunate (OART), which exhibits substantial bioactivity in vitro and vivo, and we verify its feasibility in cancer immunotherapy. For mechanism, OART induces cytoplasmic and mitochondrial LPO to promote tumor ferroptosis, via inhibiting glutathione-mediated ferroptosis defense system, enhancing iron-dependent Fenton reaction, and initiating mitochondrial LPO. The destroyed mitochondrial membrane potential, disturbed mitochondrial fusion and fission, as well as downregulation of dihydroorotate dehydrogenase mutually contribute to mitochondrial LPO. Consequently, OART enhances tumor immunogenicity by releasing damage associated molecular patterns and promoting antigen presenting cells maturation, thereby transforming tumor environment from immunosuppressive to immunosensitive. By establishing in vivo model of tumorigenesis and lung metastasis, we verified that OART improves the systematic immune response. In summary, OART has enormous clinical potential for ferroptosis-based cancer therapy in translational medicine.

Novel Pt(IV) complex OAP2 induces STING activation and pyroptosis via mitochondrial membrane remodeling for synergistic chemo-immunotherapy.

Mitochondrial membrane remodeling can trigger the release of mitochondrial DNA (mtDNA), leading to the activation of cellular oxidative stress and immune responses. While the role of mitochondrial membrane remodeling in promoting inflammation in hepatocytes is well-established, its effects on tumors have remained unclear. In this study, we designed a novel Pt(IV) complex, OAP2, which is composed of oxaliplatin (Oxa) and acetaminophen (APAP), to enhance its anti-tumor effects and amplify the immune response. Our findings demonstrate that OAP2 induces nuclear DNA damage, resulting in the production of nuclear DNA. Additionally, OAP2 downregulates the expression of mitochondrial Sam50, to promote mitochondrial membrane remodeling and trigger mtDNA secretion, leading to double-stranded DNA accumulation and ultimately synergistically activating the intracellular cGAS-STING pathway. The mitochondrial membrane remodeling induced by OAP2 overcomes the limitations of Oxa in activating the STING pathway and simultaneously promotes gasdermin-D-mediated cell pyroptosis. OAP2 also promotes dendritic cell maturation and enhances the quantity and efficacy of cytotoxic T cells, thereby inhibiting cancer cell proliferation and metastasis. Briefly, our study introduces the first novel small-molecule inhibitor that regulates mitochondrial membrane remodeling for active immunotherapy in anti-tumor research, which may provide a creative idea for targeting organelle in anti-tumor therapy.

Santacruzamate A Alleviates Pain and Pain-Related Adverse Emotions through the Inhibition of Microglial Activation in the Anterior Cingulate Cortex.

Chronic pain is a complex disease. It seriously affects patients' quality of life and imposes a significant economic burden on society. Santacruzamate A (SCA) is a natural product isolated from marine cyanobacteria in Panama. In this study, we first demonstrated that SCA could alleviate chronic inflammatory pain, pain-related anxiety, and depression emotions induced by complete Freund's adjuvant in mice while inhibiting microglial activation in the anterior cingulate cortex. Moreover, SCA treatment attenuated lipopolysaccharide (LPS)-induced inflammatory response by downregulating interleukin 1ß and 6 (IL-1ß and IL-6) and tumor necrosis factor-α (TNF-α) levels in BV2 cells. Furthermore, we found that SCA could bind to soluble epoxide hydrolase (sEH) through molecular docking technology, and the thermal stability of sEH was enhanced after binding of SCA to the sEH protein. Meanwhile, we identified that SCA could reduce the sEH enzyme activity and inhibit sEH protein overexpression in the LPS stimulation model. The results indicated that SCA could alleviate the development of inflammation by inhibiting the enzyme activity and expression of sEH to further reduce chronic inflammatory pain. Our study suggested that SCA could be a potential drug for treating chronic inflammatory pain.

Influenza A Virus PB1-F2 Induces Affective Disorder by Interfering Synaptic Plasticity in Hippocampal Dentate Gyrus.

Influenza A virus (IAV) infection, which leads to millions of new cases annually, affects many tissues and organs of the human body, including the central nervous system (CNS). The incidence of affective disorders has increased after the flu pandemic; however, the potential mechanism has not been elucidated. PB1-F2, a key virulence molecule of various influenza virus strains, has been shown to inhibit cell proliferation and induce host inflammation; however, its role in the CNS has not been studied. In this study, we constructed and injected PB1-F2 into the hippocampal dentate gyrus (DG), a region closely associated with newborn neurons and neural development, to evaluate its influence on negative affective behaviors and learning performance in mice. We observed anxiety- and depression-like behaviors, but not learning impairment, in mice injected with PB1-F2. Furthermore, pull-down and mass spectrometry analyses identified several potential PB1-F2 binding proteins, and enrichment analysis suggested that the most affected function was neural development. Morphological and western blot studies revealed that PB1-F2 inhibited cell proliferation and oligodendrocyte development, impaired myelin formation, and interfered with synaptic plasticity in DG. Taken together, our results demonstrated that PB1-F2 induces affective disorders by inhibiting oligodendrocyte development and regulating synaptic plasticity in the DG after IAV infection, which lays the foundation for developing future cures of affective disorders after IAV infection.

A novel mitochondria-targeting DHODH inhibitor induces robust ferroptosis and alleviates immune suppression.

Dihydroorotate dehydrogenase (DHODH)-mediated ferroptosis defense is a targetable vulnerability in cancer. Currently, only a few DHODH inhibitors have been utilized in clinical practice. To further enhance DHODH targeting, we introduced the mitochondrial targeting group triphenylphosphine (TPP) to brequinar (BRQ), a robust DHODH inhibitor, resulting in the creation of active molecule B2. This compound exhibits heightened anticancer activity, effectively inhibiting proliferation in various cancer cells, and restraining tumor growth in melanoma xenografts in mice. B2 achieves these effects by targeting DHODH, triggering the formation of reactive oxygen species (ROS), promoting mitochondrial lipid peroxidation, and inducing ferroptosis in B16F10 and A375 cells. Surprisingly, B2 significantly downregulates PD-L1 and alleviates immune suppression. Importantly, B2 exhibits no apparent adverse effects in mice. Collectively, these findings highlight that enhancing the mitochondrial targeting capability of the DHODH inhibitor is a promising therapeutic approach for melanoma treatment.

Degradation of Hexokinase 2 Blocks Glycolysis and Induces GSDME-Dependent Pyroptosis to Amplify Immunogenic Cell Death for Breast Cancer Therapy.

Hexokinase 2 (HK2) is the principal rate-limiting enzyme in the aerobic glycolysis pathway and determines the quantity of glucose entering glycolysis. However, the current HK2 inhibitors have poor activity, so we used proteolysis-targeting chimera (PROTAC) technology to design and synthesize novel HK2 degraders. Among them, C-02 has the best activity to degrade HK2 protein and inhibit breast cancer cells. It is demonstrated that C-02 could block glycolysis, cause mitochondrial damage, and then induce GSDME-dependent pyroptosis. Furthermore, pyroptosis induces cell immunogenic death (ICD) and activates antitumor immunity, thus improving antitumor immunotherapy in vitro and in vivo. These findings show that the degradation of HK2 can effectively inhibit the aerobic metabolism of breast cancer cells, thereby inhibiting their malignant proliferation and reversing the immunosuppressive microenvironment.

CJ2: A Novel Potent Platinum(IV) Prodrug Enhances Chemo-Immunotherapy by Facilitating PD-L1 Degradation in the Cytoplasm and Cytomembrane.

Platinum drugs as primary chemotherapy drugs have been applied to various cancer patients. However, their therapeutic applicability is limited due to the adverse effects and immunosuppression. To minimize the side effects and boost the immune response, we designed and synthesized platinum(IV) prodrugs that introduced BRD4 inhibitor JQ-1. Among them, CJ2 had the most potent therapeutic activity and less toxicity. With the introduction of ligand JQ-1, CJ2-reduced PD-L1 protein was found in the cytoplasm and cytomembrane for the first time. By interfering with the PD-L1 synthesis, CJ2 could arouse the immune system and promote CD8+ T cell infiltration. Meanwhile, CJ2 could accelerate PD-L1 degradation in the cytoplasm to block DNA damage repair. In vivo, CJ2 markedly suppressed tumor growth by reversing the immunosuppression microenvironment and enhancing DNA damage. These findings provide an effective approach to improve the selectivity and activity of the platinum drugs with elevated immune response.

Natural Product Albiziabioside A Conjugated with Pyruvate Dehydrogenase Kinase Inhibitor Dichloroacetate To Induce Apoptosis-Ferroptosis-M2-TAMs Polarization for Combined Cancer Therapy.

The reprogramming of energy metabolism is considered to be one of the main characteristics of cancer. The development of therapeutic agents targeting glycolysis to alter aberrant glucose metabolism and restore oxidative phosphorylation has emerged as an effective approach for cancer therapy. In this way, we have developed a conjugate AlbA-DCA, which can induce a marked increase in intracellular ROS and alleviate the accumulation of lactic acid in TME. Meanwhile, AlbA-DCA selectively kills cancer cells and exhibits an excellent synergistic effect. Mechanism studies confirm that AlbA-DCA can induce apoptosis and ferroptosis. We also confirm that AlbA-DCA can remold the tumor immunosuppression microenvironment via eliminating M2-TAMs to inhibit both primary and distal tumor progression in a dual-4T1 tumor model in female BALB/c mice. As a result, rational design of natural saponin and PDK inhibitor to induce apoptosis-ferroptosis-M2-TAMs polarization for enhanced cancer therapy is a promising strategy, thus providing a new idea for cancer therapy.

Enhanced cancer therapy through synergetic photodynamic/immune checkpoint blockade mediated by a liposomal conjugate comprised of porphyrin and IDO inhibitor.

Cancer metastases is still a hurdle for good prognosis and live quality of breast cancer patients. Treatment strategies that can inhibit metastatic cancer while treating primary cancer are needed to improve the therapeutic effect of breast cancer. Methods: In this study, a dual functional drug conjugate comprised of protoporphyrin IX and NLG919, a potent indoleamine-2,3-dioxygenase (IDO) inhibitor, is designed to combine photodynamic therapy and immune checkpoint blockade to achieve both primary tumor and distant metastases inhibition. Liposomal delivery is applied to improve the biocompatibility and tumor accumulation of the drug conjugate (PpIX-NLG@Lipo). A series of in vitro and in vivo experiments were carried out to examine the PDT effect and IDO inhibition activity of PpIX-NLG@Lipo, and subsequently evaluate its anti-tumor capability in the bilateral 4T1 tumor-bearing mice. Results: The in vitro and in vivo experiments demonstrated that PpIX-NLG@Lipo possess strong ability of ROS generation to damage cancer cells directly through PDT. Meanwhile, PpIX-NLG@ Lipo can induce immunogenic cell death to elicit the host immune system. Furthermore, PpIX-NLG@Lipo interferes the activity of IDO, which can amplify PDT-induced immune responses, leading to an increasing amount of CD8+ T lymphocytes infiltrated into tumor site, finally achieve both primary and distant tumor inhibition. Conclusion: This work presents a novel conjugate approach to synergize photodynamic therapy and IDO blockade for enhanced cancer therapy through simultaneously inhibiting both primary and distant metastatic tumor.

Lenvatinib-zinc phthalocyanine conjugates as potential agents for enhancing synergistic therapy of multidrug-resistant cancer by glutathione depletion.

The therapeutic efficacy of targeted therapy is dramatically hindered by multidrug resistance (MDR) because of elevated GSH levels. Thus, depletion of intracellular GSH level is highly desirable for targeted-therapeutic agents to reverse tumor drug resistance. In this study, a photosensitive multifunctional conjugate ZnPc-C8-Len, in which lenvatinib (a VEGFR inhibitor) is linked to a photosensitizer ZnPc through an alkyl chains, was synthesized to realize photodynamic therapy to reverse multidrug resistance and enhanced antitumor therapy. Upon the irradiation, ZnPc-C8-Len could generate ROS to deplete intracellular GSH. The decreased GSH would enhance apoptotic cell death by Bcl-2/caspase 3 pathway and reduce expression of P-gp to reverse lenvatinib resistance. Moreover, through PEG2000-PLA2000 encapsulation, ZnPc-C8-Len NPs displayed significantly enhanced tumor accumulation and excellent in vivo antitumor activity. And the fluorescence characteristics of ZnPc-C8-Len could monitor the changes of nanoparticles in vivo in real time to guide when and where to conduct the subsequent therapy. As a result, conjugate ZnPc-C8-Len had an outstanding capability to enhance synergistic therapy of multidrug-resistant cancer by glutathione depletion. And the approach reported here provide a promising strategy in development of conjugate integrated targeted therapy with photodynamic therapy to reverse targeted drug multidrug resistance and enhance synergistic therapy.

Novel antitumor compound optimized from natural saponin Albiziabioside A induced caspase-dependent apoptosis and ferroptosis as a p53 activator through the mitochondrial pathway.

It is highly desirable to activation p53 function with small-molecule compounds for colon cancer therapy. Triterpene saponin has been characterized with the favorable selectivity and safety profiles. However, the application of triterpene saponin as cancer chemotherapy drugs was hampered primarily by moderate anticancer potency and the lack the mechanism of action. In this study, we synthesized a series of Albiziabioside A derivatives and evaluated the antitumor activity both in vitro and in vivo. Compounds D13 possessed strong inhibitory activity against HCT116 cells with IC50 values of 5.19 µM. More importantly, compound D13 had a favorable selectivity and was efficacious against MDR cancer cells. Moreover, compound D13 could induce apoptosis and ferroptosis through the mitochondrial pathway as a p53 activator. In addition, compound D13 significantly suppressed tumorigenesis without inducing toxicity in normal organs in vivo. Collectively, this study provides a clinically relevant argument for considering triterpene saponin derivatives D13 as potential cancer therapeutic candidates with enhanced activity, acceptable safety and novel mechanisms of action. To the best of our knowledge, this compound is the first drug candidate which can induce apoptosis and ferroptosis as a p53 activator.

A tumor-targeted Ganetespib-zinc phthalocyanine conjugate for synergistic chemo-photodynamic therapy.

Therapeutic effects of photodynamic therapy (PDT) are limited by the selectivity of photosensitizer (PS). Herein, a novel tumor-targeted drug-PS conjugate (Gan-ZnPc) which integrated with zinc phthalocyanine (ZnPc) and Ganetespib has been developed. ZnPc is a promising PS with remarkable photosensitization ability. Ganetespib is a heat shock protein 90 (Hsp90) inhibitor with preferential tumor selectivity and conjugated to ZnPc as a tumor-targeted ligand. The multifunctional small molecule conjugate, Gan-ZnPc, could be bound to extracellular Hsp90 and then selectively internalized into the tumor cells, followed by the generation of abundant intracellular reactive oxygen species (ROS) upon irradiation. Besides, Gan-ZnPc can arrest cell proliferation and induce apoptosis by the inhibition of Hsp90. Herein, with combination of the inhibition of Hsp90 and the generation of cytotoxic ROS, Gan-ZnPc implements tumor selectivity, concentrated PDT and chemotherapy in a synergistic manner, which results in highly effective anti-tumor activity in vitro and in vivo.

Phthalocyanine-based coordination polymer nanoparticles for enhanced photodynamic therapy.

In the photodynamic therapy (PDT) of cancer, zinc phthalocyanine (ZnPc) as a photosensitizer possesses superior photosensitive properties. However, the therapeutic effect of ZnPc in PDT is limited due to its aggregation, low solubility and poor selectivity. In this study, charge-reversal phthalocyanine-based coordination polymer nanoparticles (PCPN) are developed for improving the curative effect of ZnPc. Tetra(4-carboxyphenoxy)-phthalocyaninatozinc(ii) (TPZnPc) is coordinated with the zinc ion to form the core of PCPN, which is coated with a lipid bilayer by self-assembly (PCPNs@Lip). TPZnPc molecules in the core of PCPN are in the monomeric state and can generate cytotoxic singlet oxygen (1O2) efficiently, which solves the solubility and aggregation problems of ZnPc. Meanwhile, 1,2-dicarboxylic-cyclohexane anhydride modified lysyl-cholesterol (DLC) is functionalized on the surface of PCPN (PCPNs@Lip/DLC), endowing PCPN with a charge-reversal ability which could be triggered by a mildly acidic tumor microenvironment. PCPNs@Lip/DLC is proved to enhance tumor cellular uptake and generate more intracellular 1O2 after irradiation. As confirmed by in vitro and in vivo studies, PCPNs@Lip/DLC remarkably increases the PDT effect. All these results demonstrate that PCPNs@Lip/DLC is a promising nanoplatform for the application of ZnPc in effective PDT.

Dual-tail approach to discovery of novel carbonic anhydrase IX inhibitors by simultaneously matching the hydrophobic and hydrophilic halves of the active site.

Dual-tail approach was employed to design novel Carbonic Anhydrase (CA) IX inhibitors by simultaneously matching the hydrophobic and hydrophilic halves of the active site, which also contains a zinc ion as part of the catalytic center. The classic sulfanilamide moiety was used as the zinc binding group. An amino glucosamine fragment was chosen as the hydrophilic part and a cinnamamide fragment as the hydrophobic part in order to draw favorable interactions with the corresponding halves of the active site. In comparison with sulfanilamide which is largely devoid of the hydrophilic and hydrophobic interactions with the two halves of the active site, the compounds so designed and synthesized in this study showed 1000-fold improvement in binding affinity. Most of the compounds inhibited the CA effectively with IC50 values in the range of 7-152 nM. Compound 14e (IC50: 7 nM) was more effective than the reference drug acetazolamide (IC50: 30 nM). The results proved that the dual-tail approach to simultaneously matching the hydrophobic and hydrophilic halves of the active site by linking hydrophobic and hydrophilic fragments was useful for designing novel CA inhibitors. The effectiveness of those compounds was elucidated by both the experimental data and molecular docking simulations. This work laid a solid foundation for further development of novel CA IX inhibitors for cancer treatment.

Natural product-based design, synthesis and biological evaluation of Albiziabioside A derivatives that selectively induce HCT116 cell death.

A series of Albiziabioside A coupled substituents of cinnamoyl derivatives were designed and synthesized. The synthesized compounds were screened for anticancer activity against a panel of six human cancer cell lines using a MTT assay. Synthetic derivatives showed excellent selectivity, as they were toxic against only HCT116 cell line. Some compounds exhibited better anti-cancer activity against HCT116 compared to positive controls, such as 5-fluorouracil and Albiziabioside A. Compound 8n was the most active derivative. Importantly, it was also found that the anti-proliferative activity of 8n could be attributed to the induction of cell cycle arrest and apoptosis in HCT116 cells.

A library of 1,2,3-triazole-substituted oleanolic acid derivatives as anticancer agents: design, synthesis, and biological evaluation.

A series of novel oleanolic acid coupled 1,2,3-triazole derivatives have been designed and synthesized by employing a Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition reaction. The anti-proliferative evaluation indicated that some compounds exhibited excellent anti-cancer activity against the examined cancer cell lines. Among all derivatives, compound 3t possesses the best inhibitory activity against HT1080 cells. A series of pharmacology experiments show that compound 3t significantly induced HT1080 cell apoptosis. Therefore, this compound can serve as a promising lead candidate for further study.

Synthesis and evaluation of the anticancer activity of albiziabioside A and its analogues as apoptosis inducers against human melanoma cells.

We have efficiently synthesized albiziabioside A (1) together with its six disaccharide analogues through a linear synthesis, and evaluated their cytotoxicity against six different skin cancer cells. All of the analogues showed weak cytotoxicity, with the exception of compound 1, which exhibited strong cytotoxicity against A375 cells. Albiziabioside A can induce cell cycle arrest in both the S and G2/M phases. Moreover, albiziabioside A can induce A375 cell apoptosis via mitochondrial pathways involving a caspase cascade. These results provide for the first time a basic mechanism for the anticancer activity of 1.

Au(I)-catalyzed triple bond alkoxylation/dienolether aromaticity-driven cascade cyclization to naphthalenes.

A novel strategy for the synthesis of multisubstituted naphthalenes was developed via a Au(i)-catalyzed alkyne alkoxylation/dienolether aromaticity-driven cascade cyclization using 1,5-enyne substrates. The functional group toleration was examined by synthesizing a series of substrates and the mechanism was also studied based on intermediates isolated through deuterium labeling experiments.