Regulating tumor glycometabolism and the immune microenvironment by inhibiting lactate dehydrogenase with platinum(iv) complexes

Inducing disulfidptosis in tumors:potential pathways and significance

Regulated cell death (RCD) is crucial for the elimination of abnormal cells. In recent years, strategies aimed at inducing RCD, particularly apoptosis, have become increasingly important in cancer therapy. However, the ability of tumor cells to evade apoptosis has led to treatment resistance and relapse, prompting extensive research into alternative death processes in cancer cells. A recent study identified a novel form of RCD known as disulfidptosis, which is linked to disulfide stress. Cancer cells import cystine from the extracellular environment via solute carrier family 7 member 11 (SLC7A11) and convert it to cysteine using nicotinamide adenine dinucleotide phosphate (NADPH). When NADPH is deficient or its utilization is impaired, cystine accumulates, leading to the formation of disulfide bonds in the actin cytoskeleton, triggering disulfidptosis. Disulfidptosis reveals a metabolic vulnerability in tumors, offering new insights into cancer therapy strategies. This review provides a detailed overview of the mechanisms underlying disulfidptosis, the current research progress, and limitations. It also highlights innovative strategies for inducing disulfidptosis and explores the potential of combining these approaches with traditional cancer therapies, particularly immunotherapy, to expedite clinical translation.

A Dual Action Platinum(IV) Complex with Self-assembly Property Inhibits Prostate Cancer through Mitochondrial Stress Pathway

Platinum(IV) prodrugs are highly promising anticancer agents because they can selectively target tumors and minimize the adverse effects associated with their PtII congeners. In this study, we synthesized dual action PtIV complexes by linking oxoplatin with lithocholic acid. The synthesized compounds, designated as PL-I, PL-II, and PL-III, can spontaneously self-assemble in water, resulting in the formation of spherical shape nanoparticles. Among the developed complexes, PL-III appeared to be the most potent compound against all the tested cancer cell lines, with 10 fold higher cytotoxicity compared to cisplatin in PC3 cells. The complex arrests the cell cycle in the S and G2 phases and induces DNA damage. Additional mechanistic investigations demonstrate that PL-III predominantly localizes within the mitochondria and cytoplasm. Consequently, PL-III disrupts mitochondrial membrane potential, increases ROS production, and perturbs mitochondrial bioenergetics in PC3 cells. The complex induces apoptosis through the mitochondrial pathway by upregulating pro-apoptotic protein expression and downregulating anti-apoptotic protein expression from the BCl-2 protein family. These results demonstrate that higher cellular uptake and reduction of PL-III by biological reductants in PC3 cells resulted in a synergistic effect of lithocholic acid and cisplatin, which can be easily observed due to its unique cytotoxic mechanism. This further underscores the significance of dual-action PtIV complexes in enhancing the efficacy of cancer therapy.

Advancements in the study of glucose metabolism in relation to tumor progression and treatment

Sugar serves as the primary energy source for mammals, with glucose metabolism facilitating energy acquisition in human cells. The proper functioning of intracellular glucose metabolism is essential for the maintenance of orderly and healthy physiological activities. Tumor cells, characterized by uncontrolled growth, exhibit dysregulated proliferation and apoptosis processes, leading to abnormal alterations in glucose metabolism. Specifically, tumor cells exhibit a shift towards aerobic glycolysis, resulting in the production of lactic acid that can be utilized as a metabolic intermediate for sustained tumor cell growth. This article provides a comprehensive overview of the enzymes involved in glucose metabolism and the alterations in gene expression that occur during tumor progression. It also examines the current research on targeting abnormal glucose metabolism processes for tumor treatment and discusses potential future directions for utilizing glucose metabolism as a therapeutic target.

Exploring Nanozymes for Organic Substrates: Building Nano-organelles

Since the discovery of the first peroxidase nanozyme (Fe3O4), numerous nanomaterials have been reported to exhibit intrinsic enzyme-like activity toward inorganic oxygen species, such as H2O2, oxygen, and O2 -. However, the exploration of nanozymes targeting organic compounds holds transformative potential in the realm of industrial synthesis. This review provides a comprehensive overview of the diverse types of nanozymes that catalyze reactions involving organic substrates and discusses their catalytic mechanisms, structure-activity relationships, and methodological paradigms for discovering new nanozymes. Additionally, we propose a forward-looking perspective on designing nanozyme formulations to mimic subcellular organelles, such as chloroplasts, termed "nano-organelles". Finally, we analyze the challenges encountered in nanozyme synthesis, characterization, nano-organelle construction and applications while suggesting directions to overcome these obstacles and enhance nanozyme research in the future. Through this review, our goal is to inspire further research efforts and catalyze advancements in the field of nanozymes, fostering new insights and opportunities in chemical synthesis.

Platinum-Metformin Conjugates Acting as Promising PD-L1 Inhibitors through the AMP-Activated Protein Kinase Mediated Lysosomal Degradation Pathway

With the development of metalloimmunology, the potential of platinum drugs in cancer immunotherapy has attracted extensive attention. Although immunochemotherapy combining PD-1/PD-L1 antibodies with platinum drugs has achieved great success in the clinic, combination therapy commonly brings new problems. Herein, we have developed a platinum-metformin conjugate as a promising alternative to antibody-based PD-L1 inhibitors, not only disrupting PD-1/PD-L1 axis on cell surface but also down-regulating the total PD-L1 levels in non-small cell lung cancer (NSCLC) cells comprehensively, thus achieving highly efficient immunochemotherapy by a single small molecule. Mechanism studies demonstrate that Pt-metformin conjugate can selectively accumulate in lysosomes, promote lysosomal-dependent PD-L1 degradation via the AMPK-TFEB pathway, and modulate the upstream regulatory proteins related to PD-L1 expression (e.g. HIF-1α and NF-κB), eventually decreasing the total abundance of PD-L1 in NSCLC, overcoming tumor hypoxia, and activating anti-tumor immunity in vivo. This work suggests an AMPK-mediated lysosomal degradation pathway of PD-L1 for the first time and provides a unique design perspective for the development of novel platinum drugs for immunochemotherapy.

Exploring the therapeutic potential of rutin through investigating its inhibitory mechanism on lactate dehydrogenase: Multi-spectral methods and computer simulation

Lactate dehydrogenase (LDH), a crucial enzyme in anaerobic glycolysis, plays a pivotal role in the energy metabolism of tumor cells, positioning it as a promising target for tumor treatment. Rutin, a plant-based flavonoid, offers benefits like antioxidant, antiapoptotic, and antineoplastic effects. This study employed diverse experiments to investigate the inhibitory mechanism of rutin on LDH through a binding perspective. The outcomes revealed that rutin underwent spontaneous binding within the coenzyme binding site of LDH, leading to the formation of a stable binary complex driven by hydrophobic forces, with hydrogen bonds also contributing significantly to sustaining the stability of the LDH-rutin complex. The binding constant (Ka) for the LDH-rutin system was 2.692 ± 0.015 × 104 M-1 at 298 K. Furthermore, rutin induced the alterations in the secondary structure conformation of LDH, characterized by a decrease in α-helix and an increase in antiparallel and parallel β-sheet, and β-turn. Rutin augmented the stability of coenzyme binding to LDH, which could potentially hinder the conversion process among coenzymes. Specifically, Arg98 in the active site loop of LDH provided essential binding energy contribution in the binding process. These outcomes might explain the dose-dependent inhibition of the catalytic activity of LDH by rutin. Interestingly, both the food additives ascorbic acid and tetrahydrocurcumin could reduce the binding stability of LDH and rutin. Meanwhile, these food additives did not produce positive synergism or antagonism on the rutin binding to LDH. Overall, this research could offer a unique insight into the therapeutic potential and medicinal worth of rutin.

Metal-detection based techniques and their applications in metallobiology

Metals are essential for human health and play a crucial role in numerous biological processes and pathways. Gaining a deeper insight into these biological events will facilitate novel strategies for disease prevention, early detection, and personalized treatment. In recent years, there has been significant progress in the development of metal-detection based techniques from single cell metallome and proteome profiling to multiplex imaging, which greatly enhance our comprehension of the intricate roles played by metals in complex biological systems. This perspective summarizes the recent progress in advanced metal-detection based techniques and highlights successful applications in elucidating the roles of metals in biology and medicine. Technologies including machine learning that couple with single-cell analysis such as mass cytometry and their application in metallobiology, cancer biology and immunology are also emphasized. Finally, we provide insights into future prospects and challenges involved in metal-detection based techniques, with the aim of inspiring further methodological advancements and applications that are accessible to chemists, biologists, and clinicians.

Cancer energy reprogramming and the immune responses

Cancer as an uncontrolled growth of cells due to existing mutation in host cells that may proliferate, induce angiogenesis and sometimes metastasize due to the favorable tumor microenvironment (TME). Since it kills more than any disease, biomedical science does not relent in studying the exact pathogenesis. It was believed to be a problem that lies in the nucleus of the host cells; however, recent oncology findings are shifting attention to the mitochondria as an adjuvant to cancer pathogenesis. The changes in the gene are strongly related to cellular metabolism and metabolic reprogramming. It is now understood that reprogramming the TME will have a direct effect on the immune cells' metabolism. Although there are a number of studies on immune cells' response towards tumor energy reprogramming and cancer progression, there is still no existence with the updated collation of these immune cells' response to distinct energy reprogramming in cancer studies. To this end, this mini review shed some light on cancer energy reprogramming mechanisms and enzyme degradation pathways, the cancer pathogenicity activity series involved with reduced lactate production, the specific immune cell responses due to the energy reprogramming. This study highlighted some prospects and future experiments in harnessing the host immune response towards the altered energy metabolism due to cancer.

Engineering a hyaluronic acid-encapsulated tumor-targeted nanoplatform with sensitized chemotherapy and a photothermal effect for enhancing tumor therapy

Chemotherapy remains one of the most widely used cancer treatment modalities in clinical practice. However, the characteristic microenvironment of solid tumors severely limits the anticancer efficacy of chemotherapy. In addition, a single treatment modality or one death pathway reduces the antitumor outcome. Herein, tumor-targeting O2 self-supplied nanomodules (CuS@DOX/CaO2-HA) are proposed that not only alleviate tumor microenvironmental hypoxia to promote the accumulation of chemotherapeutic drugs in tumors but also exert photothermal effects to boost drug release, penetration and combination therapy. CuS@DOX/CaO2-HA consists of copper sulfide (CuS)-loaded calcium peroxide (CaO2) and doxorubicin (DOX), and its surface is further modified with HA. CuS@DOX/CaO2-HA underwent photothermal treatment to release DOX and CaO2. Hyperthermia accelerates drug penetration to enhance chemotherapeutic efficacy. The exposed CaO2 reacts with water to produce Ca2+, H2O2 and O2, which sensitizes cells to chemotherapy through mitochondrial damage caused by calcium overload and a reduction in drug efflux via the alleviation of hypoxia. Moreover, under near infrared (NIR) irradiation, CuS@DOX/CaO2-HA initiates a pyroptosis-like cell death process in addition to apoptosis. In vivo, CuS@DOX/CaO2-HA demonstrated high-performance antitumor effects. This study provides a new strategy for synergistic enhancement of chemotherapy in hypoxic tumor therapy via combination therapy and multiple death pathways.

Polyphenol nanocomplex modulates lactate metabolic reprogramming and elicits immune responses to enhance cancer therapeutic effect

Cancer lactate metabolic reprogramming induces an elevated level of extracellular lactate and H+, leading to an acidic immunosuppressive tumor microenvironment (TEM). High lactic acid level may affect the metabolic programs of various cells that comprise an antitumor immune response, therefore, restricting immune-mediated tumor destruction, and leading to therapeutic resistance and unsatisfactory prognosis. Here, we report a metal-phenolic coordination-based nanocomplex loaded with a natural polyphenol galloflavin, which inhibits the function of lactate dehydrogenase, reducing the production of lactic acid, and alleviating the acidic immunosuppressive TME. Besides, the co-entrapped natural polyphenol carnosic acid and the synthetic PEG-Ce6 polyphenol derivative (serving as a photosensitizer) could induce immunogenic cancer cell death upon laser irradiation, which further activates immune system and promotes immune cell recruitment and infiltration in tumor tissues. We demonstrated that this nanocomplex-based combinational therapy could reshape the TME and elicit immune responses in a murine breast cancer model, which provides a promising strategy to enhance the therapeutic efficiency of drug-resistant breast cancer.

Development of Platinum Complexes for Tumor Chemoimmunotherapy

Platinum complexes are potential antitumor drugs in chemotherapy. Their impact on tumor treatment could be greatly strengthened by combining with immunotherapy. Increasing evidences indicate that the antitumor activity of platinum complexes is not limited to chemical killing effects, but also extends to immunomodulatory actions. This review introduced the general concept of chemoimmunotherapy and summarized the progress of platinum complexes as chemoimmunotherapeutic agents in recent years. Platinum complexes could be developed into inducers of immunogenic cell death, blockers of immune checkpoint, regulators of immune signaling pathway, and modulators of tumor immune microenvironment, etc. The synergy between chemotherapeutic and immunomodulatory effects reinforces the antitumor activity of platinum complexes, and helps them circumvent the drug resistance and systemic toxicity. The exploration of platinum complexes for chemoimmunotherapy may create new opportunities to revive the discovery of metal anticancer drugs.

ENO2 as a Biomarker Regulating Energy Metabolism to Promote Tumor Progression in Clear Cell Renal Cell Carcinoma

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the most common and metastatic type of renal cell carcinoma. Despite significant advancements, the current diagnostic biomarkers for ccRCC lack the desired specificity and sensitivity, necessitating the identification of novel biomarkers and elucidation of their underlying mechanisms.

METHODS

Three gene expression profile datasets were obtained from the GEO database, and differentially expressed genes (DEGs) were screened. Gene Ontology and KEGG pathway analysis were conducted in ccRCC. To clarify the diagnosis and prognostic role of ENO2, Kaplan-Meier analysis and Cox proportional hazards regression analysis were performed. Functional experiments were also carried out to verify the significant role of ENO2 in ccRCC. Finally, tumor mutational burden analysis was utilized to investigate the potential role of ENO2 in gene mutations in ccRCC.

RESULTS

The study showed that ENO2 is a potential biomarker for the diagnosis of ccRCC and can independently predict the clinical prognosis of ccRCC. Furthermore, we found that ENO2 can promote the occurrence and progression of ccRCC by affecting the glycolysis level of cells through the "Warburg effect".

CONCLUSIONS

These findings provide new theories for the occurrence and development of ccRCC and can help formulate new strategies for its diagnosis and treatment.