A Native Drug-Free Macromolecular Therapeutic to Trigger Mutual Reinforcing of Endoplasmic Reticulum Stress and Mitochondrial Dysfunction for Cancer Treatment

Organelle-oriented nanomedicines in tumor therapy: Targeting, escaping, or collaborating?

Precise tumor therapy is essential for improving treatment specificity, enhancing efficacy, and minimizing side effects. Targeting organelles is a key strategy for achieving this goal and is a frontier research area attracting a considerable amount of attention. The concept of organelle targeting has a significant effect on the structural design of the nanodrugs employed. Most notably, the intricate interactions among different organelles in a tumor cell essentially create a unified system. Unfortunately, this aspect might have been somewhat overlooked when existing organelle-targeting nanodrugs were designed. In this review, we underscore the synergistic relationship among the various organelles and advocate for a holistic view of organelle-targeting design. Through the integration of biology and material science, recent advancements in organelle targeting, escaping, and collaborating are consolidated to offer fresh perspectives for the development of antitumor nanomedicines.

Macrophage membrane-based biomimetic nanocarrier system for enhanced immune activation and combination therapy in liver cancer

Previous studies have demonstrated that the combination of photodynamic therapy, photothermal therapy and chemotherapy is highly effective in treating hepatocellular carcinoma (HCC). However, the clinical application of this approach has been hindered by the lack of efficient and low-toxicity drug delivery platforms. To address this issue, we developed a novel biomimetic nanocarrier platform named ZID@RM, which utilizes ZIF8 functional nanoparticles encapsulated with macrophage membrane and loaded with indocyanine green and doxorubicin. The bionic nanocarrier platform has good biocompatibility, reducing the risk of rapid clearance by macrophages and improving the targeting ability for HCC cells. Under the dual regulation of acidity and infrared light, ZID@RM stimulated the generation of abundant reactive oxygen species within HCC cells, induced tumor cell pyroptosis and promoted the release of damage-associated molecular patterns to induce immune responses. In the future, this technology platform has the potential to provide personalized and improved healthcare by using patients' own macrophage membranes to create an efficient drug delivery system for tumor therapy.Graphical abstract Scheme 1 Schematic representation of the synthesis of a biomimetic nanomedicine delivery platform (ZID@RM) and its application in tumor imaging-guided combination therapy.

Amplifying Ca2+ overload by engineered biomaterials for synergistic cancer therapy

Ca2+ overload is one of the most widely causes of inducing apoptosis, pyroptosis, immunogenic cell death, autophagy, paraptosis, necroptosis, and calcification of tumor cells, and has become the most valuable therapeutic strategy in the field of cancer treatment. Nevertheless, several challenges remain in translating Ca2+ overload-mediated therapeutic strategies into clinical applications, such as the precise control of Ca2+ dynamics, specificity of Ca2+ homeostasis dysregulation, as well as comprehensive mechanisms of Ca2+ regulation. Given this, we comprehensively reviewed the Ca2+-driven intracellular signaling pathways and the application of Ca2+-based biomaterials (such as CaCO3-, CaP-, CaO2-, CaSi-, CaF2-, and CaH2-) in mediating cancer diagnosis, treatment, and immunotherapy. Meanwhile, the latest researches on Ca2+ overload-mediated therapeutic strategies, as well as those combined with multiple-model therapies in mediating cancer immunotherapy are further highlighted. More importantly, the critical challenges and the future prospects of the Ca2+ overload-mediated therapeutic strategies are also discussed. By consolidating recent findings and identifying future research directions, this review aimed to advance the field of oncology therapy and contribute to the development of more effective and targeted treatment modalities.

Mechanistic study of tumor fluorescence response signals based on a near-infrared viscosity-sensitive probe

Viscosity is an important physiological parameter closely associated with various cellular processes and diseases. Several fluorescence probes responsive to viscosity have been developed, demonstrating high sensitivity specifically towards tumor tissues. However, the underlying core mechanism of this highly potential responsive signal has been a subject of debate, as highly sensitive probes encounter excessive environmental interferences in complex tumor tissues. Therefore, we have developed a viscosity-responsive fluorescence probe based on the classical TICT mechanism (twisted intramolecular charge transfer) as a research tool. This probe features an ultra-wide emission range of 700-1200 nm in the near-infrared spectrum, strong photostability, and simultaneous targeting of mitochondria and lysosomes. Through in-depth analysis, we have revealed the intrinsic mechanisms underlying its functionality, demonstrating that the major contributor to the fluorescence change of responsive probes during imaging is the inherent state of cells rather than the tumor microenvironment or the cell type. Our findings provide a theoretical foundation for the continued exploration and application of viscosity-responsive probes.

Mechanistic Insights into the Apoptosis of Cancer Cells Induced by a Kinase-Responsive Peptide Amphiphile

Organelle targeting is a useful approach in drug development for cancer therapy. Peptide amphiphiles are good candidates for targeting specific organelles because they can be engineered into a wide range of molecular structures, enabling customization for specific functional needs. We have developed a peptide amphiphile, C16-(EY)3, that can respond to tyrosine kinase activity and undergo phosphorylation inside cancer cells. C16-(EY)3 selectively induced apoptosis in cancer cells that overexpressed tyrosine kinase. The self-assembly of peptide amphiphiles on the endoplasmic reticulum (ER) membrane reduced the ER membrane fluidity and triggered ER stress. The mechanism of the cancer cell death induced by C16-(EY)3 was shown to involve phosphorylation by tyrosine kinase, ER stress induction, and the subsequent activation of caspase-4, -12, and -9, which ultimately triggered apoptosis through the activation of caspase-3 and -7. In vivo studies further validated the antitumor efficacy of C16-(EY)3, as transcutaneous administration of the peptide amphiphile inhibited tumor growth in mice. This study elucidated the mechanism of apoptosis induced by the peptide amphiphile, indicating the potential of peptide amphiphiles as organelle-targeting cancer therapeutics and providing a novel strategy for the development of selective and potent anticancer drugs.

Biomineralized and metallized small extracellular vesicles encapsulated in hydrogels for mitochondrial-targeted synergistic tumor therapy

Targeted organelle therapy is a promising therapeutic method for significantly regulating the tumor microenvironment, yet it often lacks effective strategies for leveraging synergistic enhancement effect. Engineered small extracellular vesicles (sEVs) are expected to address this challenge due to their notable advantages in drug delivery, extended circulation time, and intercellular information transmission. Herein, we prepare sEVs with pH and photothermal dual-responsiveness, which are encapsulated with hydrogels for a quadruple-efficient synergistic therapy. M1-phenotype macrophages-derived sEVs, which carry cytokines that inhibit tumor progression, were separately encapsulated with calcium phosphates (CaPs) and Au@Pt nanoparticles (Au@Pt NPs), endowing them with pH and photothermal dual-responsiveness. Subsequently, they were assembled into sEV-Au@Pt NPs/CaPs nanohybrids, and functionalized with mitochondria-targeting peptides. Within tumor cells, mitochondrial targeting enhances Ca2+ accumulation, resulting in mitochondrial homeostasis imbalance. The release of Pt2+ causes nuclear damage and exacerbates mitochondrial dysfunction. Furthermore, under laser irradiation, the sEV-Au@Pt NPs absorb light, generating hyperthermia that promotes the release of Ca2+ and Pt2+ from the hydrogel and cytokines from the sEVs, thereby achieving a quadruple-efficient synergistic therapy. The hydrogel effectively prolongs the retention time of nanohybrids, aiding in the prevention of tumor recurrence. These nanohybrids exhibit favorable mitochondrial targeting ability, with a Pearson's co-localization coefficient of 0.877. In experimental trials, tumor growth was significantly inhibited after only five treatments, with the tumor volume reduced to 0.16-fold that of the control group. This strategy presents a potential tailored platform for engineered sEVs in mitochondrial-targeted therapy and holds great promise for advancing organelle-targeted therapeutic strategies. STATEMENT OF SIGNIFICANCE: Engineering small extracellular vesicles (sEVs) can significantly enhance the synergistic effects of organelle-targeted therapy, thereby improving therapeutic efficacy and reducing side effects. However, their full development is still pending. In this study, we present a promising strategy that involves engineering sEVs with pH and photothermal dual-responsiveness through biomineralization and metallization, enabling quadruple synergistic tumor therapy. Our study demonstrates the remarkable synergistic effects of mitochondrial homeostasis imbalance caused by Ca2+ bursts and nuclear damage due to Pt2+ release. After five treatments, the tumor volume in the experimental group was reduced to 0.16-fold that of the control group. This strategy holds great promise for the design of engineered sEVs as organelle-targeted therapeutic systems.

Tumor microenvironment-activated polypeptide nanoparticles for oncolytic immunotherapy

Cationic oncolytic polypeptides have gained increasing attention owing to their ability to directly lyse cancer cells and activate potent antitumor immunity. However, the low tumor cell selectivity and inherent toxicity induced by positive charges of oncolytic polypeptides hinder their systemic application. Herein, a tumor microenvironment-responsive nanoparticle (DNP) is developed by the self-assembly of a cationic oncolytic polypeptide (PLP) with a pH-sensitive anionic polypeptide via electrostatic interactions. After the formation of DNP, the positive charges of PLP are shielded. DNPs can keep stable in physiological conditions (pH 7.4) but respond to acidic tumor microenvironment (pH 6.8) to release oncolytic PLP. As a result, DNPs evoke potent immunogenic cell death by disrupting cell membranes, damaging mitochondria and increasing intracellular levels of reactive oxygen species. In vivo results indicate that DNPs significantly improve the biocompatibility of PLP, and inhibit tumor growth, recurrence and metastasis by direct oncolysis and activation of antitumor immune responses. In summary, these results indicate that pH-sensitive DNPs represent a prospective strategy to improve the tumor selectivity and biosafety of cationic polymers for oncolytic immunotherapy.

Identification of endoplasmic reticulum stress and mitochondrial dysfunction related biomarkers in osteoporosis

BACKGROUND

Endoplasmic reticulum stress (ERS) and mitochondrial dysfunction (MD) involved in bone metabolism disorders. However, the particular mechanisms of ERS and MD related genes (ERS&MDRGs) in osteoporosis (OP) have not been elucidated. In present study, biomarkers related to ERS and MD in OP were identified.

METHODS

Differentially expressed genes (DEGs) were obtained based on GEO dataset. ERS&MDRGs were derived from Genecard database. Initially, ERS&MD related DEGs (ERS&MDRDEGs) were obtained by overlapping DEGs and ERS&MDRGs. The key module was screened by WGCNA. The intersection of ERS&MDRDEGs and key module was screened by machine learning to obtain key genes. Then, receiver operating characteristic curve (ROC) was drawn to calculated diagnostic accuracy of key genes. The ssGSEA and Cibersort algorithms were performed to analyze immune cell infiltration. The miRNA-mRNA-TF network were draw by cytoscape software. Moleculaer docking and DGIdb database were employed for screening potential drugs. Finally, the expression of key genes was verified by qRT-PCR.

RESULTS

The 122 ERS&MDRDEGs were obtained by preliminary screening. ERS&MDRDEGs were mainly enriched in lipid metabolism, calcium ion transport, and ossification. The 5 key genes were identified, including AAAS, ESR1, SLC12A2, TAF15, and VAMP2. Immune infiltration analysis showed monocyte and macrophage were different between OP and control groups. The miRNA-mRNA-TF regulatory network indicated has-miR-625-5p, has-miR-296-3p, CTCT and EP300 as potential regulatory targets. The 2 potential small molecule drugs, namely bumetanide and elacestrant were screened. The expression of AAAS, ESR1, VAMP2 were higher, and SLC12A2 and TAF15 were lower in OP than control group.

CONCLUSION

This research identified 5 key genes AAAS, ESR1, SLC12A2, TAF15 and VAMP2. Bumetanide and elacestrant were potential drugs. These findings provided valuable insights into the pathophysiology of OP and the development of new therapeutic strategies.

Dextran-based nanodrugs with mitochondrial targeting/glutathione depleting synergy for enhanced photodynamic therapy

The efficacy of photodynamic therapy (PDT) for malignant tumors is significantly impeded by the short diffusion distance of reactive oxygen species (ROS) and the ROS-consuming glutathione (GSH) overexpressed in tumor cells. Therefore, enhanced PDT can be achieved by the construction of biomacromolecule-based nanodrugs that can specifically target ROS-sensitive mitochondria and deplete intracellular GSH. Herein, we synthesized the dextran-based nano-assemblies by a Graft copolymerization Induced Self-Assembly (GISA) method, in which methyl acrylate and diallyl disulfide (DADS) were copolymerized from a mixed dextran/amino dextran backbone in an aqueous medium. Notably, the disulfide bond-containing DADS served as both GSH-depleting agent and GSH-responsive crosslinker. In order to develop a nanodrug with mitochondrial targeting/GSH depleting synergy, we further conjugated a mitochondria-targeting ligand onto the amino dextran corona, and developed a "loading-post-assembly" strategy to load a hydrophobic photosensitizer protoporphyrin IX or even multi-drugs into the hydrophobic core of the nano-assemblies. Cell and animal studies illustrated that the nanodrug could accumulate in the mitochondria of tumor cells to generate ROS in situ and thus eliminate tumors. Taken together, our work presents the dextran-based nanodrug as an efficient platform to achieve mitochondria-targeting PDT with an enhanced efficiency by simultaneously depleting intracellular GSH.

Mitochondria-Nucleus Migration Probe for Ultrasensitive Monitoring of mtDNA Damage in Living Cells

Mitochondrial DNA (mtDNA) damage is a prevalent phenomenon that has been proven to be implicated in a wide spectrum of diseases. However, the progressive attenuation of probe signals in response to mtDNA damage within living cells inherently limits the sensitivity and precision of current probes for detecting mtDNA damage. Herein, we employ an innovative organelle signal ratio imaging approach, utilizing the mitochondria-nucleus migration probe MCQ, to achieve unparalleled sensitivity in detecting mtDNA damage in living cells. MCQ exhibited an initial preferential binding to mtDNA, facilitated by its cationic quinolinium moiety, but migrated to the nucleus upon mtDNA damage. This unique migration behavior not only enhanced the spatial identifiability of mtDNA damage but also amplified detection sensitivity and precision significantly by harnessing the intensified nucleus signal against the attenuated mitochondrial signal. This innovative approach established a positive correlation between the signal and mtDNA damage, enabling the detection of even subtle mtDNA damage at the early stage of apoptosis with a remarkable 23-fold enhancement following just 5 min H2O2 induction in living cells, whereas conventional methods relying solely on the fading of mitochondrial signals proved insufficient. Furthermore, MCQ's ability to monitor the occurrence of mtDNA damage achieved the intricate differentiation between apoptosis and ferroptosis. By monitoring mtDNA damage, drug-induced apoptosis in cancer cells was further conducted using MCQ to evaluate the therapeutic efficacy of four anticancer drugs at very low concentrations. This innovative strategy not only paves the way for ultrasensitive detection of mtDNA damage but also holds immense promise for early monitoring of mtDNA damage-associated diseases.

TMCO1 regulates energy metabolism and mitochondrial function of hepatocellular carcinoma cells through TOMM20, affecting the growth of subcutaneous graft tumors and infiltration of CAFs

This study mainly shows the role of endoplasmic reticulum transmembrane and coiled coil domains 1 (TMCO1) in the regulatory mechanism of hepatocellular carcinoma (HCC). Invasion and migration capacity were detected by Transwell and wound healing after TMCO1 and TOMM20 overexpression and knockdown, and mitochondrial function was detected through reactive oxygen species (ROS), mitochondrial permeability transition pore (mPTP), mitochondrial membrane potential (MMP), and ATP production. A model of subcutaneous tumor formation in nude mice was established to detect the effect of TMCO1 on tumor formation. The results showed that overexpression of TMCO1 significantly promoted HCC cell metastasis, promoted cell proliferation and ATP production, inhibited cell apoptosis, mPTP opening and ROS production, mediated the increase of MMP level and cytoskeletal remodeling. However, knocking down TMCO1 can have the opposite effect. More importantly, knocking down TOMM20 can block the regulation effect of TMCO1, and TOMM20 overexpression can alleviate the inhibitory effect of knocking down TMCO1 on the development of liver cancer cells. In animal models, knockdown of TMCO1 expression significantly inhibited the growth of subcutaneous implant tumors. This suggests that TMCO1 may be a potential and valuable therapeutic target for liver cancer.

AGR2 knockdown induces ER stress and mitochondria fission to facilitate pancreatic cancer cell death

Anterior gradient 2 (AGR2) is often overexpressed in many human cancers, including pancreatic ductal adenocarcinoma (PDAC). Elevated AGR2 expression is known to play a critical role in tumor development, progression, and metastasis and positively correlates with poor patient survival. However, the relationship between AGR2 expression and tumor growth is not fully understood. Our study aims to investigate the impact of AGR2 knockdown on the survival of two pancreatic cancer cell lines, HPAF-II and PANC-1, that exhibit high AGR2 expression. This study revealed that the knockdown of AGR2 expression through an inducible shRNA-mediated approach reduced the proliferative ability and colony-forming potential of PDAC cells compared to scramble controls. Significantly, knocking down AGR2 led to the inhibition of multiple protein biosynthesis pathways and induced ER stress through unfolded protein response (UPR) activation. AGR2 knockdown induced ER stress and increased mitochondrial fission, while mitochondrial fusion remained unaffected. Ultimately, apoptotic cell death was heightened in AGR2 knockdown PDAC cells compared to the controls. Overall, these data reveal a new axis involving AGR2-ER stress-associated mitochondrial fission that could be targeted to improve PDAC patient outcomes.

Synthesis and antitumor activity of copper(II) complexes of imidazole derivatives

Complexes [Cu(PI)2(H2O)](NO3)2 (1), [Cu(PBI)2(NO3)]NO3 (2), [Cu(TBI)2(NO3)]NO3 (3), [Cu(BBIP)2](ClO4)2 (4) and [Cu(BBIP)(CH3OH)(ClO4)2] (5) were synthesized from the reactions of Cu(II) salts with 2-(2'-pyridyl)imidazole (PI), (2-(2'-pyridyl)benzimidazole (PBI), 2-(4'-thiazolyl)-benzimidazole (TBI), 2,6-bis(benzimidazol-2-yl)-pyridine (BBIP), respectively. Their compositions and crystal structures were determined. Their in-vitro antitumor activities were screened on four cancer cell lines and one normal cell line (HL-7702) using cisplatin as the positive control. Complexes 2 and 4 show higher cytotoxicity than the other three complexes. The cytotoxicity of complex 2 are comparable to those for cisplatin, and the cytotoxicity for 4 are much higher than those for cisplatin. From a viewpoint of antitumor, 2 might be a nice choice on the tumor cell line of T24 because its IC50 values on T24 and HL-7702 are 15.03 ± 1.10 and 21.34 ± 0.35, respectively. Thus, a mechanistic study for complexes 2 and 4 on T24 cells was conducted. It revealed that they can reduce mitochondrial membrane potential and increase mitochondrial membrane permeability, resulting in increased intracellular ROS levels, Ca2+ inward flow, dysfunctional mitochondria and the eventual cell apoptosis. In conclusion, they can induce cell apoptosis through mitochondrial dysfunction. These findings could be useful in the development of new antitumor agents.

Quercetin Boosts Pulsatile Gonadotropin-Releasing Hormone Release to Improve Luteal Function via Inhibiting NF-κB/NLRP3-Mediated Neuron Pyroptosis

SCOPE

Luteal phase deficiency (LPD) is the main cause of infertility without an effective cure. Quercetin (QUE) is a bioactive flavonoid with antioxidant properties, while its role in treating LPD remains unclear. This study aims to investigate the therapeutic effects of QUE on infertility and menstrual disorders induced by LPD, thus further exploring the underlying mechanism.

METHODS AND RESULTS

Mifepristone-induced rats are used to explore the protective effects of QUE against LPD. QUE stimulates the spontaneous secretion of progesterone to improve luteal function and endometrial receptivity in LPD rats by activating the kisspeptin/GPR54 system to facilitate the gonadotropin-releasing hormone (GnRH) pulsatility. Bioinformatics analysis reveals that the core mechanism of QUE in treating LPD is to attenuate the GnRH neuron pyroptosis by inhibiting the NF-κB pathway, which is further verified in LPD rats and lipopolysaccharide (LPS)-treated GT1-7, as QUE significantly reduces the expression of key factors concerning NF-κB pathway and NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome.

CONCLUSION

This study first proposes that neuron pyroptosis-induced GnRH pulsatility disruption accounts for the pathogenesis of LPD, and QUE facilitates the pulse secretion of GnRH to boost the spontaneous progesterone secretion by inhibiting NF-κB/NLRP3-mediated neuron pyroptosis, which provides a new therapeutic target and strategy for LPD.

Hollow Calcium/Copper Bimetallic Amplifier for Cuproptosis/Paraptosis/Apoptosis Cancer Therapy via Cascade Reinforcement of Endoplasmic Reticulum Stress and Mitochondrial Dysfunction

The endoplasmic reticulum (ER) and mitochondria are essential organelles that play crucial roles in maintaining cellular homeostasis. The simultaneous induction of ER stress and mitochondrial dysfunction represents a promising yet challenging strategy for cancer treatment. Herein, a hollow calcium-copper bimetallic nanoplatform is developed as a cascade amplifier to reinforce ER stress and mitochondrial dysfunction for breast cancer treatment. For this purpose, we report a facile method for preparing hollow CaCO3 (HCC) nanoparticles by regulating the dissolution-recrystallization process of amorphous CaCO3, and the amplifier D@HCC-CuTH is meticulously fabricated by sequentially coating disulfiram-loaded HCC nanoparticles with a copper coordination polymer and hyaluronan. In tumor cells, the dithiocarbamate-copper complex generated in situ by liberated disulfiram and Cu2+ inhibits the ubiquitin-proteasome system, causing irreversible ER stress and intracellular Ca2+ redistribution. Meanwhile, the amplifier induces mitochondrial dysfunction via triggering a self-amplifying loop of mitochondrial Ca2+ burst, and reactive oxygen species augment. Additionally, Cu2+ induces dihydrolipoamide S-acetyltransferase oligomerization in mitochondria, further exacerbating mitochondrial damage via cuproptosis. Collectively, ER stress amplification and mitochondrial dysfunction synergistically induce a cuproptosis-paraptosis-apoptosis trimodal cell death pathway, which demonstrates significant efficacy in suppressing tumor growth. This study presents a paradigm for synchronously inducing subcellular organelle disorders to boost cancer multimodal therapy.

Novel SERCA2 inhibitor Diphyllin displays anti-tumor effect in non-small cell lung cancer by promoting endoplasmic reticulum stress and mitochondrial dysfunction

Abnormal calcium signaling is associated with non-small cell lung cancer (NSCLC) malignant progression, poor survival and chemotherapy resistance. Targeting endoplasmic reticulum (ER) Ca2+ channels or pumps to block calcium uptake in the ER induces ER stress and concomitantly promotes mitochondrial calcium uptake, leading to mitochondrial dysfunction and ultimately inducing cell death. Here, we identified Diphyllin was a potential specific inhibitor of endoplasmic reticulum (ER) calcium-importing protein sarco/endoplasmic-reticulum Ca2+ ATPase 2 (SERCA2). In vitro and in vivo studies showed that Diphyllin increased NSCLC cell apoptosis, along with inhibition of cell proliferation and migration. Mechanistically, Diphyllin promoted ER stress by directly inhibiting SERCA2 activity and decreasing ER Ca2+ levels. At the same time, the accumulated Ca2+ in cytoplasm flowed into mitochondria to increase reactive oxygen species (ROS) and decrease mitochondrial membrane potential (MMP), leading to cytochrome C (Cyto C) release and mitochondrial dysfunction. In addition, we found that Diphyllin combined with cisplatin could have a synergistic anti-tumor effect in vitro and in vivo. Taken together, our results suggested that Diphyllin, as a potential novel inhibitor of SERCA2, exerts anti-tumor effects by blocking ER Ca2+ uptake and thereby promoting ER stress and mitochondrial dysfunction.

An "Iron-phagy" nanoparticle inducing irreversible mitochondrial damages for antitumor therapy

Cellular iron is inseparably related with the proper functionalities of mitochondria for its potential to readily donate and accept electrons. Though promising, the available endeavors of iron chelation antitumor therapies have tended to be adjuvant therapies. Herein, we conceptualized and fabricated an "iron-phagy" nanoparticle (Dp44mT@HTH) capable of inducing the absolute devastation of mitochondria via inhibiting the autophagy-removal of impaired ones for promoting cancer cell death. The Dp44mT@HTH with hyaluronic acid (HA) as hydrophilic shell can specifically target the highly expressed CD44 receptors on the surface of 4T1 tumor cells. After internalization and lysosomal escape, the nanoparticle disassembles in response to the reactive oxygen species (ROS), subsequently releasing the iron chelator Dp44mT and autophagy-inhibitory drug hydroxychloroquine (HCQ). Dp44mT can then seize cellular Fe2+ to trigger mitochondrial dysfunction via respiratory chain disturbance, while HCQ not only lessens Fe2+ intake, but also impedes fusions of autophagosomes and lysosomes. Consequentially, Dp44mT@HTH induces irreversible mitochondrial impairments, in this respect creating a substantial toxic stack state that induces apoptosis and cell death. Initiating from the perspective of endogenous substances, this strategy illuminates the promise of iron depletion therapy via irreversible mitochondrial damage induction for anticancer treatment.

A Pyroptosis-Inducing Arsenic(III) Nanomicelle Platform for Synergistic Cancer Immunotherapy

Immunogenic cell death (ICD) could activate anti-tumor immune responses, which is highly attractive for improving cancer treatment effectiveness. Here, this work reports a multifunctional arsenic(III) allosteric inhibitor Mech02, which induces excessive accumulation of 1O2 through sensitized biocatalytic reactions, leading to cell pyroptosis and amplified ICD effect. After Mech02 is converted to Mech03, it could actualize stronger binding effects on the allosteric pocket of pyruvate kinase M2, further interfering with the anaerobic glycolysis pathway of tumors. The enhanced DNA damage triggered by Mech02 and the pyroptosis of cancer stem cells provide assurance for complete tumor clearance. In vivo experiments prove nanomicelle Mech02-HA NPs is able to activate immune memory effects and raise the persistence of anti-tumor immunity. In summary, this study for the first time to introduce the arsenic(III) pharmacophore as an enhanced ICD effect initiator into nitrogen mustard, providing insights for the development of efficient multimodal tumor therapy agents.

Layer-by-Layer Nanoparticles for Calcium Overload in situ Enhanced Reactive Oxygen Oncotherapy

Background

Challenges such as poor drug selectivity, non-target reactivity, and the development of drug resistance continue to pose significant obstacles in the clinical application of cancer therapeutic drugs. To overcome the limitations of drug resistance in chemotherapy, a viable treatment strategy involves designing multifunctional nano-platforms that exploit the unique physicochemical properties of tumor microenvironment (TME).

Methods

Herein, layer-by-layer nanoparticles with polyporous CuS as delivery vehicles, loaded with a sonosensitizer (tetra-(4-aminophenyl) porphyrin, TAPP) and sequentially functionalized with pH-responsive CaCO3, targeting group hyaluronic acid (HA) were designed and synthesized for synergistic treatment involving chemodynamic therapy (CDT), sonodynamic therapy (SDT), photothermal therapy (PTT), and calcium overload. Upon cleavage in an acidic environment, CaCO3 nanoparticles released TAPP and Ca2+, with TAPP generating 1O2 under ultrasound trigger. Exposed CuS produced highly cytotoxic ·OH in response to H2O2 and also exhibited a strong PTT effect.

Results

CuS@TAPP-CaCO3/HA (CTCH) delivered an enhanced ability to release more Ca2+ under acidic conditions with a pH value of 6.5, which in situ causes damage to HeLa mitochondria. In vitro and in vivo experiments both demonstrated that mitochondrial dysfunction greatly amplified the damage caused by reactive oxygen species (ROS) to tumor, which strongly confirms the synergistic effect between calcium overload and reactive oxygen therapy.

Conclusion

Collectively, the development of CTCH presents a novel therapeutic strategy for tumor treatment by effectively responding to the acidic TME, thus holding significant clinical implications.

Multimodal optoacoustic imaging: methods and contrast materials

Optoacoustic (OA) imaging offers powerful capabilities for interrogating biological tissues with rich optical absorption contrast while maintaining high spatial resolution for deep tissue observations. The spectrally distinct absorption of visible and near-infrared photons by endogenous tissue chromophores facilitates extraction of diverse anatomic, functional, molecular, and metabolic information from living tissues across various scales, from organelles and cells to whole organs and organisms. The primarily blood-related contrast and limited penetration depth of OA imaging have fostered the development of multimodal approaches to fully exploit the unique advantages and complementarity of the method. We review the recent hybridization efforts, including multimodal combinations of OA with ultrasound, fluorescence, optical coherence tomography, Raman scattering microscopy and magnetic resonance imaging as well as ionizing methods, such as X-ray computed tomography, single-photon-emission computed tomography and positron emission tomography. Considering that most molecules absorb light across a broad range of the electromagnetic spectrum, the OA interrogations can be extended to a large number of exogenously administered small molecules, particulate agents, and genetically encoded labels. This unique property further makes contrast moieties used in other imaging modalities amenable for OA sensing.

Oxygen self-sufficient nanodroplet composed of fluorinated polymer for high-efficiently PDT eradicating oral biofilm

Oral biofilm is the leading cause of dental caries, which is difficult to completely eradicate because of the complicated biofilm structure. What's more, the hypoxia environment of biofilm and low water-solubility of conventional photosensitizers severely restrict the therapeutic effect of photodynamic therapy (PDT) for biofilm. Although conventional photosensitizers could be loaded in nanocarriers, it has reduced PDT effect because of aggregation-caused quenching (ACQ) phenomenon. In this study, we fabricated an oxygen self-sufficient nanodroplet (PFC/TPA@FNDs), which was composed of fluorinated-polymer (FP), perfluorocarbons (PFC) and an aggregation-induced emission (AIE) photosensitizer (Triphenylamine, TPA), to eradicate oral bacterial biofilm and whiten tooth. Fluorinated-polymer was synthesized by polymerizing (Dimethylamino)ethyl methacrylate, fluorinated monomer and 1-nonanol monomer. The nanodroplets could be protonated and behave strong positive charge under bacterial biofilm acid environment promoting nanodroplets deeply penetrating biofilm. More importantly, the nanodroplets had extremely high PFC and oxygen loading efficacy because of the hydrophobic affinity between fluorinated-polymer and PFC to relieve the hypoxia environment and enhance PDT effect. Additionally, compared with conventional ACQ photosensitizers loaded system, PFC/TPA@FNDs could behave superior PDT effect to ablate oral bacterial biofilm under light irradiation due to the unique AIE effect. In vivo caries animal model proved the nanodroplets could reduce dental caries area without damaging tooth structure. Ex vivo tooth whitening assay also confirmed the nanodroplets had similar tooth whitening ability compared with commercial tooth whitener H2O2, while did not disrupt the surface microstructure of tooth. This oxygen self-sufficient nanodroplet provides an alternative visual angle for oral biofilm eradication in biomedicine.

Bisbiguanide analogs induce mitochondrial stress to inhibit lung cancer cell invasion

Targeting cancer metabolism to limit cellular energy and metabolite production is an attractive therapeutic approach. Here, we developed analogs of the bisbiguanide, alexidine, to target lung cancer cell metabolism and assess a structure-activity relationship (SAR). The SAR led to the identification of two analogs, AX-4 and AX-7, that limit cell growth via G1/G0 cell-cycle arrest and are tolerated in vivo with favorable pharmacokinetics. Mechanistic evaluation revealed that AX-4 and AX-7 induce potent mitochondrial defects; mitochondrial cristae were deformed and the mitochondrial membrane potential was depolarized. Additionally, cell metabolism was rewired, as indicated by reduced oxygen consumption and mitochondrial ATP production, with an increase in extracellular lactate. Importantly, AX-4 and AX-7 impacted overall cell behavior, as these compounds reduced collective cell invasion. Taken together, our study establishes a class of bisbiguanides as effective mitochondria and cell invasion disrupters, and proposes bisbiguanides as promising approaches to limiting cancer metastasis.

Transformable Magnetic Liquid-Metal Nanoplatform for Intracellular Drug Delivery and MR Imaging-Guided Microwave Thermochemotherapy

Improved techniques for the administration of chemotherapeutic drugs are required to enhance tumor therapy efficacy and reduce the side effects of chemotherapy due to insufficient targeting and limited intratumoral drug release. Controlled drug delivery systems combined with thermotherapy are expected to play an important role in personalized tumor therapy. Herein, a novel microwave-responsive transformable magnetic liquid-metal (MLM) nanoplatform is designed for effective endosomal escape that facilitates intracellular drug delivery and enhanced anticancer therapy. The MLM nanoplatform exhibits a sensitive magnetic resonance imaging function for imaging-guided therapy and brilliant synergistic effects of chemotherapy with microwave thermal therapy to kill tumor cells. Once endocytosed by targeted tumor cells, the deep penetration of microwave energy can be absorbed by the MLM nanoplatform to convert heat and reactive oxygen species, which induces the shape transformation from nanospheres to large rods, resulting in the physical disruption of the endosomal membrane for intracellular drug release. Furthermore, the MLM nanoplatform synergistic therapy could activate immunomodulatory effects by M1 macrophage polarization and T cell infiltration, thus inhibiting tumor growth and lung metastasis. This work based on microwave-driven transformable magnetic liquid-metal nanoplatform provides novel ways to precisely control drug delivery and high-efficiency cancer therapy.

Unfolded Protein-Based Sandwich AIE Probe Imparts High Fluorescent Contrast for Pan-Cancer Surgical Navigation

Fluorescence imaging-guided navigation for cancer surgery has a promising clinical application. However, pan-cancer encompasses a wide variety of cancer types with significant heterogeneity, resulting in the lack of universal and highly contrasted fluorescent probes for surgical navigation. Here, we developed an aggregation-induced emission (AIE) probe (MI-AIE-TsG, MAT) with dual activation for pan-cancer surgical navigation. MAT weakly activates fluorescence by targeting the SUR1 protein on the endoplasmic reticulum (ER) through the TsG group. Subsequently, the sulfhydryl groups on the unfolded proteins, which are highly enriched in cancer ER, react with the maleimide (MI) of MAT through the thiol-ene click reaction, further enhancing the fluorescence. The formation of a SUR1-MAT-unfolded protein sandwich complex reinforces the restriction of intramolecular motion and eliminates photoinduced electron transfer of MAT, leading to high signal-to-noise (9.2) fluorescence imaging and use for surgical navigation of pan-cancer. The generally high content of unfolded proteins in cancer cells makes MAT imaging generalizable, and it currently has proven feasibility in ovarian, cervical, and breast cancers. Meanwhile, MAT promotes cellular autophagy by hindering protein folding, thereby inhibiting cancer cell proliferation. This generalizable, high-contrast AIE fluorescent probe spans the heterogeneity of pancreatic cancer, enabling precise pancreatic cancer surgery navigation and treatment.

Intricate subcellular journey of nanoparticles to the enigmatic domains of endoplasmic reticulum

It is evident that site-specific systemic drug delivery can reduce side effects, systemic toxicity, and minimal dosage requirements predominantly by delivering drugs to particular pathological sites, cells, and even subcellular structures. The endoplasmic reticulum (ER) and associated cell organelles play a vital role in several essential cellular functions and activities, such as the synthesis of lipids, steroids, membrane-associated proteins along with intracellular transport, signaling of Ca2+, and specific response to stress. Therefore, the dysfunction of ER is correlated with numerous diseases where cancer, neurodegenerative disorders, diabetes mellitus, hepatic disorder, etc., are very common. To achieve satisfactory therapeutic results in certain diseases, it is essential to engineer delivery systems that can effectively enter the cells and target ER. Nanoparticles are highly biocompatible, contain a variety of cargos or payloads, and can be modified in a pliable manner to achieve therapeutic effectiveness at the subcellular level when delivered to specific organelles. Passive targeting drug delivery vehicles, or active targeting drug delivery systems, reduce the nonselective accumulation of drugs while reducing side effects by modifying them with small molecular compounds, antibodies, polypeptides, or isolated bio-membranes. The targeting of ER and closely associated organelles in cells using nanoparticles, however, is still unsymmetrically understood. Therefore, here we summarized the pathophysiological prospect of ER stress, involvement of ER and mitochondrial response, disease related to ER dysfunctions, essential therapeutics, and nanoenabled modulation of their delivery to optimize therapy.

Pioglitazone-Enhanced Brown Fat Whitening Contributes to Weight Gain in Diet-Induced Obese Mice

INTRODUCTION

Pioglitazone is an insulin sensitizer used for the treatment of type 2 diabetes mellitus (T2DM) by activating peroxisome proliferator-activated receptor gamma. This study aimed to investigate the effects of pioglitazone on white adipose tissue (WAT) and brown adipose tissue (BAT) in diet-induced obese (DIO) mice.

METHODS

C57BL/6 mice were treated with pioglitazone (30 mg/kg/day) for 4 weeks after a 16-week high-fat diet (HFD) challenge. Body weight gain, body fat mass, energy intake, and glucose homeostasis were measured during or after the treatment. Histopathology was observed by hematoxylin and eosin, oil red O, immunohistochemistry, and immunofluorescence staining. Expression of thermogenic and mitochondrial biogenesis-related genes was detected by quantitative real-time PCR and western blotting.

RESULTS

After 4-week pioglitazone treatment, the fasting blood glucose levels, glucose tolerance, and insulin sensitivity were significantly improved, but the body weight gain and fat mass were increased in DIO mice. Compared with the HFD group, pioglitazone did not significantly affect the weights of liver and WAT in both subcutaneous and epididymal regions. Unexpectedly, the weight of BAT was increased after pioglitazone treatment. Histological staining revealed that pioglitazone ameliorated hepatic steatosis, reduced the adipocyte size in WAT, but increased the adipocyte size in BAT.

CONCLUSION

Though pioglitazone can promote lipolysis, thermogenesis, and mitochondrial function in WAT, it leads to impaired thermogenesis, and mitochondrial dysfunction in BAT. In conclusion, pioglitazone could promote the browning of WAT but led to the whitening of BAT; the latter might be a new potential mechanism of pioglitazone-induced weight gain during T2DM treatment.

Thiol-Responsive Polypeptide Sulfur Dioxide Prodrug Nanoparticles for Effective Tumor Inhibition

Sulfur dioxide (SO2) based gas therapy has emerged as a novel anticancer therapeutic strategy because of its high therapeutic efficacy and biosafety. To precisely adjust the SO2 content and control gas release, herein, a thiol-responsive polypeptide SO2 prodrug mPEG-block-poly(2-amino-6-(2,4-dinitrophenylsulfonamido)hexanoic acid) (PEG-b-PLys-DNs) was designed and facilely synthesized by polymerization of a novel N-carboxyanhydride SO2-NCA. The anticancer potential of the self-assembled nanoparticles (SO2-NPs) was investigated in detail. First, PEG-b-PLys-DNs were synthesized by ring-opening polymerization of SO2-NCA, which self-assembled into NPs sized 88.4 nm in aqueous. Subsequently, SO2-NPs were endocytosed into 4T1 cells and quickly released SO2 under a high concentration of glutathione in tumor cells. This process depleted cellular glutathione, generated reactive oxygen species, and dramatically increased oxidative stress, which led to cancer cell apoptosis. Finally, the in vivo anticancer efficacy of SO2-NPs was verified in 4T1-tumor-bearing mice. Our results indicated that this novel SO2 polymeric prodrug has great potential in eradicating tumors.

Lumpy Skin Disease Virus Infection Activates Autophagy and Endoplasmic Reticulum Stress-Related Cell Apoptosis in Primary Bovine Embryonic Fibroblast Cells

Poxviruses have been associated with humans for centuries. From smallpox to mpox to lumpy skin disease virus (LSDV), members of the poxvirus family have continued to threaten the lives of humans and domestic animals. A complete understanding of poxvirus-mediated cellular processes will aid in the response to challenges from the viruses. In this study, we demonstrate that LSDV infection results in an abnormal ultrastructure of the endoplasmic reticulum (ER) lumen in primary bovine embryonic fibroblast (BEF) cells, and we further show that an ER imbalance occurs in LSDV-infected BEF cells. Additionally, we believe that ER stress-related apoptosis plays a role in the late apoptosis of BEF cells infected with LSDV, primarily through the activation of the CCAAT/enhancer binding protein homologous protein (CHOP)-Caspase-12 signal. In addition to cell apoptosis, a further investigation showed that LSDV could also activate autophagy in BEF cells, providing additional insight into the exact causes of LSDV-induced BEF cell death. Our findings suggest that LSDV-induced BEF cell apoptosis and autophagy may provide new avenues for laboratory diagnosis of lumpy skin disease progression and exploration of BEF cell processes.