Acidity generated by the tumor microenvironment drives local invasion

Designing live bacterial therapeutics for cancer

Humans are home to a diverse community of bacteria, many of which form symbiotic relationships with their host. Notably, tumors can also harbor their own unique bacterial populations that can influence tumor growth and progression. These bacteria, which selectively colonize hypoxic and acidic tumor microenvironments, present a novel therapeutic strategy to combat cancer. Advancements in synthetic biology enable us to safely and efficiently program therapeutic drug production in bacteria, further enhancing their potential. This review provides a comprehensive guide to utilizing bacteria for cancer treatment. We discuss key considerations for selecting bacterial strains, emphasizing their colonization efficiency, the delicate balance between safety and anti-tumor efficacy, and the availability of tools for genetic engineering. We also delve into strategies for precise spatiotemporal control of drug delivery to minimize adverse effects and maximize therapeutic impact, exploring recent examples of engineered bacteria designed to combat tumors. Finally, we address the underlying challenges and future prospects of bacterial cancer therapy. This review underscores the versatility of bacterial therapies and outlines strategies to fully harness their potential in the fight against cancer.

Dual-responsive nanoscale ultrasound contrast agent as an oxidative stress amplifier for enhanced DNA damage in BRCA-proficient ovarian cancer

PARP inhibitor (PARPi)-based synthetic lethal therapies have displayed limited benefits in BRCA-proficient ovarian cancer. To potentiate the application of PARPi, an ultrasound contrast agent OLA-NDs for delivery of the PARPi olaparib (OLA) was established for enhancing DNA damage by blocking DNA repair. OLA-NDs were endowed with endogenous pH- and exogenous ultrasound (US)-responsiveness to target tumors, as well as contrast-enhanced US imaging for diagnostic and therapeutic integration. OLA-NDs could upregulate NOX4 to induce oxidative stress and sensitize BRCA wild-type A2780 cells to DNA oxidative damage through the utilization of ultrasound-targeted microbubble destruction (UTMD). In addition, the strategy further increased ROS production by interfering with mitochondrial function, thereby exacerbating DNA double-strand breaks (DSBs) and inducing mitochondria-mediated apoptosis. As a consequence, the combined application of UTMD and OLA-NDs demonstrated significant antitumor effects in vitro and in vivo. This combined strategy of amplifying oxidative damage improved lethality by promoting DNA DSBs and apoptosis with reduced adverse side effects, which would provide new insight for the clinical application of PARPi in BRCA-proficient ovarian cancer.

Cobalt carbonate nanorods enhance chemotherapy via neutralization of acidic tumor microenvironment and generation of carbonate radical anions for necrosis

One of the hallmarks of cancer is the acidic extracellular space surrounding the tumor, which is linked to metabolic reprogramming and the use of glycolysis. Additionally, the acidic tumor microenvironment (TME) establishes a physiological barrier called "ion trapping" and significantly lowers the ability of cells to absorb weak-base chemotherapy agents. Although CO32- containing agents and nanoformulations could effectively neutralize the tumor acidity, the CO32- based therapeutic effect was insufficiently investigated. Herein, we fabricated cobalt carbonate (CoCO3) nanorods as drug carriers with acidity-responsive dissociation and acidity neutralization properties for the loading of hydrophobic and weak-basic drugs, evodiamine (EVO). After effective surface modification, CoCO3-PEG-EVO could effectively accumulate in the tumor and inhibit the growth of the tumor. On the one hand, acidity neutralization of CoCO3-PEG-EVO could lead to the ion trapping overcome and cellular uptake of EVO enhancement for effective cancer cell apoptosis. On the other hand, the high level of H2O2 in the tumor and HCO3- from dissociated CoCO3-PEG-EVO could cause the generation of CO3·- through a Fenton-like reaction while not hydroxyl radical (·OH) for cancer cell necrosis. Our results thus point to a potent yet easily prepared CoCO3 nanosystem (CoCO3-PEG-EVO) to induce cancer cell death, and because of its well-defined composition and excellent biocompatibility, it may be used in clinical settings in the future.

Hollow heterojunction nanocages of zeolitic imidazolate framework-8@zinc sulfide@copper sulfide for synergistic tumor therapy

The tumor microenvironment (TME) poses significant challenges for achieving efficient cancer remission through monotherapy, making multimodal synergistic therapy a key strategy in tumor treatment. Here, we designed and constructed a hollow core-shell nanocage based on zeolitic imidazolate framework-8 (ZIF-8), zeolitic imidazolate framework-8@zinc sulfide@copper sulfide (ZIF-8@ZnS@CuS, denoted as ZZCS), for the combined application of chemodynamic therapy (CDT), photothermal therapy (PTT) and photocatalytic therapy (PCT). The Cu2+ ions in ZZCS imparted peroxidase (POD)-like and catalase (CAT)-like activities, enabling the generation of toxic hydroxyl radicals (OH) through POD-like catalysis to enhance CDT effect, while also reacting with overexpressed glutathione (GSH) to elevate intracellular reactive oxygen species (ROS) levels. To overcome the inhibitory effects of hypoxia on PCT in the TME, ZZCS catalyzed the production of O2 from endogenous hydrogen peroxide (H2O2) via CAT-like activity, alleviating hypoxia and enhancing the PCT effect. Furthermore, hollow core-shell heterojunction structure of ZZCS exhibited excellent near-infrared absorption and multiple light reflection effects. Under 808 nm laser irradiation, ZZCS showed a high photothermal conversion efficiency (η = 78.1 %) and generated significant amounts of ROS (OH, O2-, 1O2), enabling the synergistic elimination of tumor cells via PTT and PCT. Benefiting from the combined CDT/PTT/PCT effects, ZZCS demonstrated excellent therapeutic efficacy in vivo, nearly eradicating tumors. This study may provide a promising foundation and potential direction for advancing multimodal tumor therapy. Future studies will focus on conducting long-term investigations to systematically evaluate the efficacy of ZZCS core-shell nanocages in achieving durable tumor eradication.

GPR65 Inactivation in Tumor Cells Drives Antigen-Independent CAR T-cell Resistance via Macrophage Remodeling

SIGNIFICANCE

The study identifies GPR65 as an important determinant of B-cell acute lymphoblastic leukemia response to CAR T-cell therapy. Notably, GPR65 absence signals CAR T resistance. By emphasizing the therapeutic potential of targeting VEGFA or host macrophages, our study identifies routes to optimize CAR T-cell therapy outcomes in hematologic malignancies via tumor microenvironment manipulation.

pH-responsive carbohydrate polymer-based nanoparticles in cancer therapy

Using the specific features of the tumor microenvironment (TME) for the development and design of novel nanomaterials can improve the capacity in tumor suppression. One of the prominent features of the TME is the mild acidic pH. Therefore, the development of pH-responsive nanoparticles can lead to the release of cargo and therapeutics at the tumor site, improving the selectivity and specificity. The materials used for the development of nanoparticles should possess a number of unique features including biocompatibility and anti-cancer activity. Hence, a special attention has been directed towards the use of carbohydrate polymers in the development of nanoparticles. The carbohydrate polymers can develop smart nanoparticles respond to the pH in TME to increase targeting ability and provide controlled drug release. Such approach is also beneficial in decreasing the side effects of systemic chemotherapy. The pH-responsive nanoparticles developed from carbohydrate polymers can be also used for the combination chemotherapy/immunotherapy/phototherapy of cancer. Furthermore, these nanoparticles demonstrate theranostic application capable of cancer diagnosis and therapy. Further attention to the large-scale production, biocompatibility and long-term safety of carbohydrate polymer-based pH-responsive nanoparticles should be directed to improve the clinical translation in the treatment of cancer patients.

The pentose phosphate pathway (PPP) in the glioma metabolism: A potent enhancer of malignancy

The glioma hallmark includes reprogramming metabolism to support biosynthetic and bioenergetic demands, as well as to maintain their redox equilibrium. It has been suggested that the pentose phosphate pathway (PPP) and glycolysis are directly involved in the dynamics and regulation of glioma cell proliferation and migration. The PPP is implicated in cellular redox homeostasis and the modulation of signaling pathways, which play a fundamental role in the progression of tumors to malignant grades, metastasis, and drug resistance. Several studies have shown that in glioblastoma cells, the activity, expression, and metabolic flux of some PPP enzymes increase, leading to heightened activity of the pathway. This generates higher levels of DNA, lipids, cholesterol, and amino acids, favoring rapid cell proliferation. Due to the crucial role played by the PPP in the development of glioma cells, enzymes from this pathway have been proposed as potential therapeutic targets. This review summarizes and highlights the role that the PPP plays in glioma cells and focuses on the key functions of the enzymes and metabolites generated by this pathway, as well as the regulation of the PPP. The studies described in this article enrich the understanding of the PPP as a therapeutic tool in the search for pharmacological targets for the development of a new generation of drugs to treat glioma.

Potentiation of immune checkpoint blockade with a pH-sensitizer as monitored in two pre-clinical tumor models with acidoCEST MRI

BACKGROUND

Tumor acidosis causes resistance to immune checkpoint blockade (ICB). We hypothesized that a "pH-sensitizer" can increase tumor extracellular pH (pHe) and improve tumor control following ICB. We also hypothesized that pHe measured with acidoCEST MRI can predict improved tumor control with ICB.

METHODS

We tested the effects of pH-sensitizers on proton efflux rate (PER), cytotoxicity, T cell activation, tumor immunogenicity, tumor growth and survival using 4T1 and B16-F10 tumor cells. We measured in vivo tumor pHe of 4T1 and B16-F10 models with acidoCEST MRI.

RESULTS

Among the pH-sensitizers tested, someprazole caused the greatest reduction in PER without exhibiting cytotoxicity or reducing T cell activation. Esomeprazole improved 4T1 tumor control with ICB administered one day after the pH-sensitizer. Tumor pHe positively correlated with TCF-1 + CD4 effector and CD8 T cell intratumoral frequencies and predicted improved 4T1 tumor control with ICB. For comparison, esomeprazole had a mild effect on B16-F10 tumor pHe, and worsened tumor control with ICB and increased intratumoral myeloid and dendritic cell (DC) frequencies.

CONCLUSIONS

A pH-sensitizer can improve tumor control with ICB, and acidoCEST MRI can be used to measure pHe and predict tumor control, but only in the 4T1 model and not the B16-F10 model.

Multifunctional Bioactive Dual-Layered Nanofibrous Matrix for Effective Breast Cancer Therapy and Enhanced Wound Healing

Surgical resection is the primary treatment for triple-negative breast cancer (TNBC). Post-operative complications, including tumor recurrence and bacterial infections, hinder complete remission and long-term recovery. To address these challenges, a multifunctional bioactive dual-layered nanofibrous matrix (MBDL-NanoMat) featuring adaptive shape control, excellent wound adherence, tunable drug release profiles, and superior biocompatibility for post-surgical applications is developed. The MBDL-NanoMat comprises a hydrophilic (HyPhil) layer and a hydrophobic (HyPhob) layer, offering distinct functionalities. The HyPhil layer, electrospun with gelatin and copper peroxide nanoparticles (Cu NPs), rapidly releases Cu NPs to induce anticancer effects through chemodynamic therapy (CDT), ferroptosis, and cuproptosis along with antibacterial action. Near-infrared laser irradiation enhances therapeutic efficacy through photothermal therapy (PTT). The HyPhob layer ensures prolonged therapeutic effects by releasing therapeutic molecules, such as rapamycin, enabling sustained chemotherapy (CT) and antibacterial activity. This synergistic therapeutic system integrates multiple mechanisms-CT, CDT, PTT, ferroptosis, and cuproptosis-suppressing tumor recurrence and accelerating wound healing. Preclinical results demonstrated enhanced angiogenesis, collagen deposition, and dermal regeneration without systemic safety. In short, the MBDL-NanoMat platform offers a unique advantage in post-surgical TNBC care by simultaneously targeting tumor recurrence and facilitating wound healing. Further investigation of this platform can significantly improve oncological and regenerative medicine strategies.

Crosstalk of lactate metabolism-related subtypes, establishment of a prognostic signature and immune infiltration characteristics in colon adenocarcinoma

Colon adenocarcinoma (COAD) is a common malignant tumor of digestive tract and lactate metabolism has been linked to tumor development and progression. In this study, we sought to investigate the influence of lactate metabolism-related genes (LRGs) prognosis. We also aimed to identify distinct LRG-related clusters and develop a risk signature for assessing patient prognosis, immunological characteristics, and response to therapy. We analyzed data from The Cancer Genome Atlas (TCGA) to reveal the expression and mutational features of LRGs in COAD patients. In the integrated TCGA and GSE39582 cohort, consensus clustering analysis was employed to classify patients into two distinct LRG-related clusters. Using differentially expressed genes (DRGs) from these two clusters, we established a LRG-related gene cluster and prognostic signature which was used to classify patients into high-risk and low-risk groups. An validation cohort was used to validate the predictive ability of risk signature and expression of 6 candidate LRGs was confirmed through quantitative real-time PCR (qRT-PCR). Nomograms were created to visually represent the clinical value of LRG-related signature. Furthermore, we extensively examined differences in immune cell infiltration, tumor mutational load (TMB), microsatellite instability (MSI) and drug sensitivity between two risk groups. Analysis of the integrated TCGA and GSE39582 cohorts revealed two distinct LRG-related clusters and gene clusters with significant differences in overall survival (OS) and tumor microenvironment. We developed a LRG-related signature comprising 6 candidate LRGs that reliably predicted OS and qRT-PCR validation confirmed the expression of LRGs. Based on the median risk score, patients were divided into low-risk and high-risk groups, with low-risk group showing better survival. Furthermore, patients in high-risk group were more sensitive to chemotherapy and associated with higher TMB, higher proportion of MSI-H. Our study provides a valuable method for guiding clinical management and personalized treatment of COAD patients, which offers new insights into individualized treatment strategies, ultimately improving patient outcomes.

siRNA-based Therapeutics in Hormone-driven Cancers: Advancements and benefits over conventional treatments

Hormone-related cancers, also known as hormone-sensitive or hormone-dependent cancers, rely on hormones such as estrogen, testosterone, and progesterone for growth. These malignancies, including breast, pituitary, thyroid, ovarian, uterine, cervical, and prostate cancers, often exhibit accelerated progression in response to hormonal signaling. Small interfering RNA (siRNA) has emerged as a groundbreaking gene suppression therapy since the FDA approval of its first product in 2018. With over 200 ongoing clinical trials, siRNA is being actively explored as a targeted treatment for hormone-related cancers. Its ability to silence specific oncogenes offers significant advantages over conventional therapies, which are often associated with toxicity, resistance, and non-specific targeting. However, challenges in siRNA delivery remain a major barrier to its clinical translation, limiting its ability to reach target cells effectively. This review evaluates the potential of siRNA in hormone-related cancers, addressing the shortcomings of traditional treatments while examining novel strategies to enhance siRNA delivery and overcome tumor microenvironment obstacles. Notably, no existing literature comprehensively consolidates siRNA-based therapies for these cancers, emphasizing the importance of this manuscript in bridging current knowledge gaps and advancing the translational application of siRNA therapeutics.

Tumor Microenvironment Lactate: Is It a Cancer Progression Marker, Immunosuppressant, and Therapeutic Target?

The "Warburg effect" is a term coined a century ago for the preferential use of glycolysis over aerobic respiration in tumor cells for energy production, even under aerobic conditions. Although this is a less efficient mechanism of generating energy from glucose, aerobic glycolysis, in addition to the canonical anaerobic glycolysis, is an effective means of lactate production. The abundant waste product, lactate, yielded by the dual glycolysis in a tumor, has been discovered to be a major biomolecule that drives cancer progression. Lactate is a metabolic energy source that, via cell membrane lactate transporters, shuttles in and out of cancer cells as well as cancer cell-associated stromal cells and immune cells within the tumor microenvironment (TME). Additionally, lactate serves as a pH tuner, signaling ligand and transducer, epigenetic and gene transcription regulator, TME modifier, immune suppressor, chemoresistance modulator, and prognostic marker. With such broad functionalities, the production-consumption-reproduction of TME lactate fuels tumor growth and dissemination. Here, we elaborate on the lactate sources that contribute to the pool of lactate in the TME, the functions of TME lactate, the influence of the TME lactate on immune cell function and local tissue immunity, and anticancer therapeutic approaches adopting lactate manipulations and their efficacies. By scrutinizing these properties of the TME lactate and others that have been well addressed in the field, it is expected that a better weighing of the influence of the TME lactate on cancer development, progression, prognosis, and therapeutic efficacy can be achieved.

An acidic microenvironment promotes lymphatic metastasis of melanoma by Thy-1 in endothelial cells and integrin αvβ3 in tumor cells

Melanoma tissues exhibit an acidic microenvironment compared with that of surrounding normal tissues. However, the effects of acidic conditions on the lymphatic metastasis, a crucial prognostic factor for patients with melanoma, are unclear. In the present study, we aimed to investigate the role of the acidic microenvironment in the function of lymphatic endothelial cells. We first conducted gene expression profiling using human dermal lymphatic endothelial cells (HDLECs) treated with low pH media. Based on these results, we focused on Thy-1/CD90, whose expression increased in a time-dependent manner in HDLECs under acidic conditions. Immunohistochemical analysis of primary tumor tissues in a mouse melanoma model revealed an increased expression of Thy-1 in lymphatic endothelial cells. The expression of integrin αvβ3, a receptor for Thy-1, was also up-regulated in melanoma cells under acidic conditions. The adhesion of HDLECs to melanoma cells was accelerated under acidic conditions, which was reduced by Thy-1 knockdown in HDLECs. Furthermore, lymphatic metastasis was significantly attenuated in a mouse melanoma metastasis model when inoculated with integrin αv-silenced melanoma cells. These results suggest that acid-induced Thy-1 in lymphatic endothelial cells, as well as integrin αvβ3 in melanoma cells, may promote their mutual cellular adhesion, contributing to lymphatic metastasis.

Copper peroxide incorporated BSA-NPs: a pH-responsive, self-supplying source of reactive oxygen species for cancer cell destruction via polarization of macrophages to the M1 phenotype

Herein, we produced self-assembled CuPer-BSA nanoparticles (NPs) formed as a result of incorporation of copper peroxide into bovine serum albumin (BSA) and serving as a self-supplying source of Cu2+ and H2O2 at biologically relevant acidic pH, and in these conditions activating a Fenton-type reaction to generate hydroxyl radicals (˙OH). ROS-induced polarization of RAW 264.7 macrophages to the M1 phenotype resulted in cellular secretions that showed significant anti-cancer efficacy against HeLa cells.

Benign non-immune cells in tumor microenvironment

The tumor microenvironment (TME) is a highly complex and continuous evolving ecosystem, consisting of a diverse array of cellular and non-cellular components. Among these, benign non-immune cells, including cancer-associated fibroblasts (CAFs), adipocytes, endothelial cells (ECs), pericytes (PCs), Schwann cells (SCs) and others, are crucial factors for tumor development. Benign non-immune cells within the TME interact with both tumor cells and immune cells. These interactions contribute to tumor progression through both direct contact and indirect communication. Numerous studies have highlighted the role that benign non-immune cells exert on tumor progression and potential tumor-promoting mechanisms via multiple signaling pathways and factors. However, these benign non-immune cells may play different roles across cancer types. Therefore, it is important to understand the potential roles of benign non-immune cells within the TME based on tumor heterogeneity. A deep understanding allows us to develop novel cancer therapies by targeting these cells. In this review, we will introduce several types of benign non-immune cells that exert on different cancer types according to tumor heterogeneity and their roles in the TME.

The Hallmarks of Cancer as Eco-Evolutionary Processes

SIGNIFICANCE

Viewing the hallmarks as a sequence of adaptations captures the "why" behind the "how" of the molecular changes driving cancer. This eco-evolutionary view distils the complexity of cancer progression into logical steps, providing a framework for understanding all existing and emerging hallmarks of cancer and developing therapeutic interventions.

Peptide-modified nanoparticles for doxorubicin delivery: Strategies to overcome chemoresistance and perspectives on carbohydrate polymers

Chemotherapy serves as the primary treatment for cancers, facing challenges due to the emergence of drug resistance. Combination therapy has been developed to combat cancer drug resistance, yet it still suffers from lack of specific targeting of cancer cells and poor accumulation at the tumor site. Consequently, targeted administration of chemotherapy medications has been employed in cancer treatment. Doxorubicin (DOX) is one of the most frequently used chemotherapeutics, functioning by inhibiting topoisomerase activity. Enhancing the anti-cancer effects of DOX and overcoming drug resistance can be accomplished via delivery by nanoparticles. This review will focus on the development of peptide-DOX conjugates, the functionalization of nanoparticles with peptides, the co-delivery of DOX and peptides, as well as the theranostic use of peptide-modified nanoparticles in cancer treatment. The peptide-DOX conjugates have been designed to enhance the targeted delivery to cancer cells by interacting with receptors that are overexpressed on tumor surfaces. Moreover, nanoparticles can be modified with peptides to improve their uptake in tumor cells via endocytosis. Nanoparticles have the ability to co-deliver DOX along with therapeutic peptides for enhanced cancer treatment. Finally, nanoparticles modified with peptides can offer theranostic capabilities by facilitating both imaging and the delivery of DOX (chemotherapy).

Metabolic Dialogue Shapes Immune Response in the Tumor Microenvironment

The fate of immune cells is fundamentally linked to their metabolic program, which is also influenced by the metabolic landscape of their environment. The tumor microenvironment represents a unique system for intercellular metabolic interactions, where tumor-derived metabolites suppress effector CD8+ T cells and promote tumor-promoting macrophages, reinforcing an immune-suppressive niche. This review will discuss recent advancements in metabolism research, exploring the interplay between various metabolites and their effects on immune cells within the tumor microenvironment.

Mechanistic study of enhanced drug release in mixed pH-responsive peptide-loaded liposomes

Liposomes serving as nanocarriers offer significant advantages in drug delivery for tumor treatment. There still exists challenges in controlling drug release by disintegrating the liposome membrane for the improvement of therapeutic efficiency. In this paper, a novel method involving the mixture of short peptides with pH-responsive characteristics into the cargo has been introduced. This approach facilitates the release of doxorubicin (DOX) in the acidic tumor tissue environment. The efficacy of this improvement was elucidated through molecular dynamics simulations and experiments. Liposomes incorporating a 1:1 ratio of peptides-DOX exhibited pronounced pH sensitivity and an enhanced drug release profile. The underlying mechanism is attributed to the peptides entering tumor tissues and undergoing protonation in acidic conditions, which increases the hydrophilicity of the peptide-DOX clusters and the internal surface tension of the liposomes. This alteration disrupts the balance between the inner and outer surface tensions of the nanocarrier, causing the liposomes to structurally disintegrate and thus enhancing drug release. The results from both thermodynamic analysis results and experimental data confirm the augmented drug release efficiency of this method, offering valuable theoretical insights for nanoparticle design and determining the optimal mixing ratio for therapeutic applications.

Antigen-Targeting Inserted Nanomicelles Guide Pre-Existing Immunity to Kill Head and Neck Cancer

A significant challenge in cancer therapy is the identification of suitable targets that are specifically and uniformly expressed across heterogeneous tumors. The efficacy of pre-existing antiviral immunity in tumor treatment is limited by the absence of corresponding targets. This study develops a novel platform of antigen-targeted inserted nanomicelles, preS1 (an antigen of hepatitis B virus)-pHLIP nanomicelles, in which tumor-targeting nanomicelles release antigens that label tumor tissue for pre-existing immunity-mediated lysis in situ. In animal models of head and neck cancers, including head and neck squamous cell carcinoma and anaplastic thyroid cancer, preS1-pHLIP nanomicelles effectively inhibited tumor growth, recurrence, and metastasis in animals pre-immunized with preS1. This therapeutic effect is associated with an increase in the proportion of preS1-specific B cells and activated tumor-specific T cells within the tumor microenvironment. Overall, this work has engineered a nanomicelle that can disguise tumor cells as viruses and achieve tumor killing through the pre-existing antiviral immune response. This strategy presents a novel approach for treating tumors with ambiguous therapeutic target profiles.

Overcoming cross-reactivity of antibodies against human lactate dehydrogenase

Lactate dehydrogenase subunit A (LD-A) plays an important role in cancer regulation and therapy. We attempted to develop an enzyme-linked immune-solvent assay (ELISA) for LD-A in human serum. However, commercial antibodies against LD-A exhibited cross-reactivity with an unknown protein. The unknown protein was purified and characterized by protein sequencing and Western blotting. In addition, we attempted to prepare a specific antibody for the ELISA using partially synthesized peptides of LD-A as immunogens. The epitope position in LD-A was carefully selected based on bioinformatics analysis. Peptide sequencer elucidated a ten amino acid sequence of the purified protein at the N-terminal. A BLAST search revealed that this sequence perfectly matched that at the N-terminus of the IgG heavy chain (H-chain). Furthermore, we demonstrated that twelve commercially available antibodies targeting LD-A or LD-B (subunit B) primarily cross-reacted with IgG or its H-chain, with only one specific antibody for each subunit. As the specific antibody against LD-A is no longer commercially accessible, we successfully produced two kinds of specific antibodies using partially synthesized LD-A peptides as immunogens. In conclusion, we have successfully produced specific antibodies against LD-A. Moreover, our findings underscore the utility of bioinformatics tools for determining the optimal positions of immunizing peptides.

Emerging Roles of Nanozyme in Tumor Metabolism Regulation: Mechanisms, Applications, and Future Directions

Nanozymes, nanomaterials with intrinsic enzyme activity, have garnered significant attention in recent years due to their catalytic abilities comparable to natural enzymes, cost-effectiveness, high catalytic activities, and stability against environmental fluctuations. As functional analogs of natural enzymes, nanozymes participate in various critical metabolic processes, including glucose metabolism, lactate metabolism, and the maintenance of redox homeostasis, all of which are essential for normal cellular functions. However, disruptions in these metabolic pathways frequently promote tumorigenesis and progression, making them potential therapeutic targets. While several therapies targeting tumor metabolism are currently in clinical or preclinical stages, their efficacy requires further enhancement. Consequently, nanozymes that target tumor metabolism are regarded as a promising therapeutic strategy. Despite extensive studies investigating the application of nanozymes in tumor metabolism, relevant reviews are relatively scarce. This article first introduces the physicochemical properties and biological behaviors of nanozymes. Subsequently, we analyze the role of nanozymes in tumor metabolism and explore their potential applications in tumor therapy. In conclusion, this review aims to foster innovative research in related fields and advance the development of nanozyme-based strategies for cancer diagnostics and therapeutics.

Targeted nanodelivery systems for personalized cancer therapy

Conventional cancer therapies such as chemotherapy face challenges such as poor tumor targeting, systemic toxicity, and drug resistance. Nanotechnology offers solutions through advanced drug delivery systems that preferentially accumulate in tumors while avoiding healthy tissues. Recent innovations have enabled the optimization of engineered nanocarriers for extended circulation and tumor localization via both passive and active targeting mechanisms. Passive accumulation exploits the leaky vasculature of tumors, whereas active strategies use ligands to selectively bind cancer cell receptors. Multifunctional nanoparticles also allow the combination of imaging, multiple therapeutic modalities and on-demand drug release within a single platform. Overall, precisely tailored nanotherapeutics that leverage unique pathophysiological traits of malignancies provide opportunities to overcome the limitations of traditional treatment regimens. This emerging field promises more effective and personalized nanomedicine approaches to detect and treat cancer. The key aspects highlighted in this review include the biological barriers associated with nanoparticles, rational design principles to optimize nanocarrier pharmacokinetics and tumor uptake, passive and active targeting strategies, multifunctionality, and reversal of multidrug resistance.

Framework Nucleic Acids: Innovative Tools for Cellular Sensing and Therapeutics

As emerging biomaterials, framework nucleic acids (FNAs) have recently demonstrated great potential in the biomedical field due to their high programmability, biocompatibility, unique structural diversity, and precise molecular design capabilities. This review focuses on the applications of FNAs in cellular sensing and disease treatment. First, we systematically introduce the applications of FNAs in cellular sensing, including their precise recognition and response to the extracellular tumor microenvironment, cell membrane proteins, and intracellular biomarkers. Subsequently, we review the potential of FNAs in disease treatment, covering their applications and development in drug delivery, regulation of cell behavior, and immunomodulation. We also discuss the limitations and potential role of FNAs in personalized medicine, precision diagnostics, and advanced therapies. The broad application of FNAs is expected to drive significant breakthroughs in future biomedical technological innovations and clinical translation.

Uncovering the protective role of lipid droplet accumulation against acid-induced oxidative stress and cell death in osteosarcoma

Extracellular acidosis stemming from altered tumor metabolism promotes cancer progression by enabling tumor cell adaptation to the hostile microenvironment. In osteosarcoma, we have previously shown that acidosis increases tumor cell survival alongside substantial lipid droplet accumulation. In this study, we explored the role of lipid droplet formation in mitigating cellular stress induced by extracellular acidosis in osteosarcoma cells, thereby enhancing tumor survival during progression. Specifically, we examined how lipid droplets shield against reactive oxygen species induced by extracellular acidosis. We demonstrated that lipid droplet biogenesis is critical for acid-exposed tumor cell survival, as it starts shortly after acid exposure (24 h) and inversely correlates with ROS levels (DCFH-DA assay), lipid peroxidation (Bodipy assay), and the antioxidant response, as also revealed by NRF2 transcript. Additionally, extracellular metabolites, such as lactate, and interaction with mesenchymal stromal cells within the tumor microenvironment intensify lipid droplet build-up in osteosarcoma cells. Critically, upon targeting two key proteins implicated in LD formation - PLIN2 and DGAT1 - cell viability significantly declined while ROS production escalated. In summary, our findings underscore the vital reliance of acid-exposed tumor cells on lipid droplet formation to scavenge oxidative stress. We conclude that the rewiring of lipid metabolism driven by microenvironmental cues is of paramount importance for the survival of metabolically altered osteosarcoma cells in acidic condition. Overall, we suggest that targeting key members of lipid droplet biogenesis may eradicate more aggressive and resistant tumor cells, uncovering potential new treatment strategies for osteosarcoma.

Glucose oxidase-driven self-accelerating drug release nanosystem based on metal-phenolic networks orchestrates tumor chemotherapy and ferroptosis-based therapy

Nanocarriers responding to tumor microenvironment have been extensively exploited to improve the antitumor outcome of chemotherapeutic drugs. However, selectively and completely releasing drugs within the tumor remains a challenge, thereby limiting the therapeutic effect of drug delivery nanosystem. To tackle this challenge, a metal-phenolic networks (MPNs)-based nanosystem (F-MGD) showing the capability of self-accelerating drug release was originally fabricated in this study. Glucose oxidase (GOx) encapsulated in F-MGD could conduct the glucose transformation in tumor to cause the oxygen consumption and the production of gluconic acid and H2O2. Therefore, F-MGD with acid and hypoxia sensitivities thoroughly disintegrated under the aggravated acidity and hypoxia to achieve a more complete drug release. Besides, the product of H2O2 was readily decomposed into hydroxyl radicals via the iron ion-mediated Fenton reaction, which markedly augmented the oxidative stress in tumor cells and promoted ferroptosis. The results of both in vitro and in vivo assays demonstrated the significant antitumor efficacy of F-MGD. Collectively, this study proposes a strategy to expedite drug release in tumor and improve the tumor treatment effect by combining ferroptosis-based therapy and chemotherapy.

Challenges and compromises: Predicting unbound antibody structures with deep learning

Therapeutic antibodies are manufactured, stored and administered in the free state; this makes understanding the unbound form key to designing and improving development pipelines. Prediction of unbound antibodies is challenging, specifically modelling of the CDRH3 loop, where inaccuracies are potentially worse due to a bias in structural data towards antibody-antigen complexes. This class imbalance provides a challenge for deep learning models trained on this data, potentially limiting generalisation to unbound forms. Here we discuss the importance of unbound structures in antibody development pipelines. We explore how the latest generation of structure predictors can provide new insights and assess how conformational heterogeneity may influence binding kinetics. We hypothesise that generative models may address some of these issues. While prediction of antibodies in complex is essential, we should not ignore the need for progress in modelling the unbound form.

Simultaneously delivery of functional gallium ions and hydrogen sulfide to endow potentiated treatment efficacy in chemo- and PARPi-resistant ovarian cancer

Limited therapeutic options are available for patients with platinum-resistant ovarian cancer (OC). Herein, we developed gallium sulfide-embedded bovine serum albumin nanoformulations (Ga2S3-BSA NMs) with a size of ~ 11 nm via a self-assembly approach. As the nanoformulations degraded in an acidic cancer microenvironment, Ga3+ and H2S gas were simultaneously released to exert their combined anticancer effects. In A2780-CIS and SKOV3-CIS platinum-resistant OC cells, Ga3+ and H2S released from Ga2S3-BSA NMs synergistically enhanced DNA damage, which arrested the cell cycle at S and G2/M phases and suppressed cell proliferation. Meanwhile, Ga2S3-BSA NMs significantly inhibited NF-κB signaling and Bcl2 protein expression, leading to cell apoptosis. Furthermore, Ga2S3-BSA NMs increased cellular lipid peroxidation and triggered ferroptosis. RNA-seq analysis further clarified the comprehensive antitumor mechanisms of Ga2S3-BSA NMs. More importantly, the therapeutic efficacy of Ga2S3-BSA NMs and their ability to enhance the sensitivity to carboplatin and fluzoparib with negligible toxicity were further confirmed in a platinum-resistant OC animal model. Altogether, our results demonstrated a potentially safe and practical strategy by using Ga2S3-BSA NMs to combat drug resistance in platinum-resistant OC.

Role of solute carrier transporters in ovarian cancer (Review)

Solute carrier (SLC) transporters are involved in various biological processes associated with metabolic reprogramming and cancer, supporting the increased requirement of nutrients and energy. Over the past decade, there have been significant advancements in understanding the expression and function of SLCs in ovarian cancer (OC). This gynecological condition has a high mortality rate and limited treatment options; thus, early diagnosis remains a target clinically. OC exhibits complexity and heterogeneity, resulting in different clinical characteristics, resistance to chemotherapy drugs and poor prognosis. Additionally, SLCs have a different expression pattern between healthy and tumor tissue, and consequently, their inhibition or activation could modify signaling pathways involved in the tumor growth process, such as cell proliferation, apoptosis and drug accumulation. The present review aims to consolidate current data to provide a comprehensive understanding of the potential importance of SLCs in OC. Additionally, it seeks to offer guidance for further research on utilizing SLCs as prognostic biomarkers and therapeutic targets.

Platinum(IV)-Backboned Polymer Prodrug-Functionalized Manganese Oxide Nanoparticles for Enhanced Lung Cancer Chemoimmunotherapy via Amplifying Stimulator of Interferon Genes Activation

The stimulator of interferon genes (STING) pathway exhibits great potential in remodeling the immunosuppressive tumor microenvironment and initiating antitumor immunity. However, how to effectively activate STING and avoid undesired toxicity after systemic administration remains challenging. Herein, platinum(IV)-backboned polymer prodrug-coated manganese oxide nanoparticles (DHP/MnO2NP) with pH/redox dual responsive properties are developed to precisely release cisplatin and Mn2+ in the tumor microenvironment and synergistically amplify STING activation. In vitro, we demonstrate that DHP/MnO2NP can effectively induce tumor cell DNA damage and leak into the cytoplasm, cooperating with Mn2+ to promote STING activation and significantly upregulate the expression of proinflammatory cytokines. Additionally, DHP/MnO2NP can selectively release cisplatin and Mn2+ to mediate tumor killing while reducing toxicity to normal cells. In vivo, DHP/MnO2NP exerted increased therapeutic efficacy by inducing STING activation and initiating robust antitumor immunity. Specifically, DHP/MnO2NP effectively skewed tumor-associated macrophages toward a proinflammatory phenotype and upregulated the expression of proinflammatory cytokines in tumors by up to 99-fold relative to the control. And the infiltration of CD8+ T cells was also significantly increased. When STING signaling was blocked, the antitumor effects and immunostimulatory efficacy of DHP/MnO2NP were significantly inhibited. Moreover, DHP/MnO2NP possess the advantage of enhanced tumor homing and retention, resulting in stronger and longer-lasting anticancer effects. Overall, DHP/MnO2NP provide a potential platform for potentiating cancer chemoimmunotherapy and hold promise for precision treatment.

Reprogramming the melanoma and immunosuppressive myeloid cells with esomeprazole-loaded PLGA nanoparticles

Proton pump inhibitors have been explored for potentiating cancer therapies via reverting the tumor acidity and promoting the activation of anti-tumor immune responses. To regulate the intracellular pH of melanoma and immunosuppressive myeloid cells, we developed poly(L-lactide-co-glycolide) nanoparticles loaded with esomeprazole (ESO-NPs). The effect of ESO-NPs on melanoma cells was observed as alkalinization and reduction of melanin content accompanied by a decrease of microphthalmia-associated transcription factor (MITF), poliovirus receptor (PVR), and programmed death ligand 1 (PD-L1) immune checkpoint expression. ESO-NP treatment of melanoma-patient-derived and in vitro-induced myeloid-derived suppressor cells (MDSCs) reduced the expression of immunosuppression-associated molecules PD-L1, CD206, and CD163 on patient-derived myeloid cells while inducing the expression of co-stimulatory molecule CD86 and HLA-DR in the in vitro model. Our findings suggest that reprogramming the intracellular pH of melanoma and immune-suppression-associated myeloid cells with ESO-NPs can modulate the expression of proteins involved in resistance to cancer therapy and immunosuppression, thus potentially improving the response to immunotherapies.

Leveraging Single-Cell Multi-Omics to Decode Tumor Microenvironment Diversity and Therapeutic Resistance

Recent developments in single-cell multi-omics technologies have provided the ability to identify diverse cell types and decipher key components of the tumor microenvironment (TME), leading to important advancements toward a much deeper understanding of how tumor microenvironment heterogeneity contributes to cancer progression and therapeutic resistance. These technologies are able to integrate data from molecular genomic, transcriptomic, proteomics, and metabolomics studies of cells at a single-cell resolution scale that give rise to the full cellular and molecular complexity in the TME. Understanding the complex and sometimes reciprocal relationships among cancer cells, CAFs, immune cells, and ECs has led to novel insights into their immense heterogeneity in functions, which can have important consequences on tumor behavior. In-depth studies have uncovered immune evasion mechanisms, including the exhaustion of T cells and metabolic reprogramming in response to hypoxia from cancer cells. Single-cell multi-omics also revealed resistance mechanisms, such as stromal cell-secreted factors and physical barriers in the extracellular matrix. Future studies examining specific metabolic pathways and targeting approaches to reduce the heterogeneity in the TME will likely lead to better outcomes with immunotherapies, drug delivery, etc., for cancer treatments. Future studies will incorporate multi-omics data, spatial relationships in tumor micro-environments, and their translation into personalized cancer therapies. This review emphasizes how single-cell multi-omics can provide insights into the cellular and molecular heterogeneity of the TME, revealing immune evasion mechanisms, metabolic reprogramming, and stromal cell influences. These insights aim to guide the development of personalized and targeted cancer therapies, highlighting the role of TME diversity in shaping tumor behavior and treatment outcomes.

Electrical and fluorescence in situ monitoring of tumor microenvironment-based pH-responsive polymer dot coated surface

A boronate-ester structure forming a pH-responsive polymer dot (Plu-PD) coated biosensor between carbonized-sp2 rich dopamine-alginate [PD(Alg)] and boronic acid-grafted Pluronic (BA-Pluronic) was developed for the electrochemical and fluorescence detection of cancer cells. The reduced fluorescence (FL) resulting from fluorescence resonance energy transfer (FRET) mediated by π-π interactions within Plu-PD was successfully reinvigorated through the specific cleavage of the boronate-ester bond, triggered by the acidic conditions prevailing in the cancer microenvironment. The anomalous variations in extracellular pH levels observed in cancer (pH ∼6.8), as opposed to the normal cellular pH range of approximately 7.4, serve as robust indicators for discerning cancer cells from their healthy counterparts. Moreover, the Plu-PD coated surface demonstrated remarkable adaptability in modulating its surface structure, concurrently exhibiting tunable electroconductivity under reduced pH conditions, thereby imparting selective responsiveness to cancer cells. The pH-modulated conductivity change was validated by a reduction in resistance from 211 ± 9.7 kΩ at pH 7.4 to 73.9 ± 9.4 kΩ and 61.5 ± 11.5 kΩ at pH 6.8 and 6.0, respectively. The controllable electrochemical characteristics were corroborated through in vitro treatment of cancer cells (HeLa, B16F10, and SNU-C2A) via LED experiments and wireless output analysis. In contrast, identical treatments yielded a limited response in normal cell line (CHO-K1). Notably, the Plu-PD coated surface can be seamlessly integrated with a wireless system to facilitate real-time monitoring of the sensing performance in the presence of cancer and normal cells, enabling rapid and accurate cancer diagnosis using a smartphone.

Application progress of nanomaterials in the treatment of prostate cancer

Prostate cancer is one of the most common malignant tumors in men, which seriously threatens the survival and quality of life of patients. At present, there are serious limitations in the treatment of prostate cancer, such as drug tolerance, drug resistance and easy recurrence. Sonodynamic therapy and chemodynamic therapy are two emerging tumor treatment methods, which activate specific drugs or sonosensitizers through sound waves or chemicals to produce reactive oxygen species and kill tumor cells. Nanomaterials are a kind of nanoscale materials with many excellent physical properties such as high targeting, drug release regulation and therapeutic monitoring. Sonodynamic therapy and chemodynamic therapy combined with the application of nanomaterials can improve the therapeutic effect of prostate cancer, reduce side effects and enhance tumor immune response. This article reviews the application progress of nanomaterials in the treatment of prostate cancer, especially the mechanism, advantages and challenges of nanomaterials in sonodynamic therapy and chemodynamic therapy, which provides new ideas and prospects for research in this field.

Positive associations between dietary potential acid load and renal cancer incidence and mortality: Results from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening trial

OBJECTIVES

To explore the relationships between dietary potential acid load and renal cancer (RC) incidence and mortality.

STUDY DESIGN

A prospective cohort study involving 97,166 U S. adults aged 55-74 years.

METHODS

Data utilized in this study were drawn from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). Dietary potential acid load was assessed by dietary acid load (DAL), potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores using a validated Diet History Questionnaire (DHQ). Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for RC incidence and mortality with adjustment for potential confounders. Restricted cubic spline (RCS) plots were utilized to reveal whether there were nonlinear associations between the DAL, PRAL, and NEAP scores and RC incidence and mortality.

RESULTS

During a follow-up period of 859,907 and 1,467,573 person-years, 423 RC cases and 221 mortality cases were documented. DAL, PRAL, and NEAP scores were positively associated with RC incidence (DAL: HR 1.41; 95% CI 1.05, 1.90; P-trend = 0.010; PRAL: HR 1.45; 95% CI 1.10, 1.91; P-trend = 0.010; NEAP: HR 1.39; 95% CI 1.04, 1.85; P-trend = 0.029). Similar associations were observed between DAL, PRAL, and NEAP scores and RC mortality. The RCS plots demonstrated a nonlinear association between DAL score and RC risk, while a linear association was observed between DAL score and RC mortality. Similar linear associations were found between PRAL and NEAP scores and RC incidence and mortality.

CONCLUSION

A higher dietary potential acid load was associated with higher risk of RC incidence and mortality in American adults.

Intratumoral lactic acid neutralization strategy for boosting chemoimmunotherapy using liposomal sodium bicarbonate

Glycolysis-related lactic acid overproduction creates an "ion-trapping" barrier and immunosuppressive tumor microenvironment that compromise effective intratumoral drug delivery and therapy. Therefore, normalization of tumor microenvironment via lactic acid neutralization can be a promising avenue for overcoming this therapeutic hurdle. In this study, the flexible liposomes loaded with sodium bicarbonate (NaHCO3@Flip) were used as a nano-adjuvant to boost chemoimmunotherapy. Their effects on assisting DOXIL and anti-programmed cell death protein 1 (PD-1) therapy were investigated. NaHCO3@Flip achieved deep tumor penetration, with the ability to neutralize lactic acid and normalize the acidic tumor microenvironment. NaHCO3@Flip is biosafe and can enhance cellular uptake efficiency of doxorubicin (DOX) by overcoming the ion-trapping barrier and amplify immunogenic cell death induced by DOX. The combination therapy of liposomal DOX and NaHCO3@Flip demonstrated enhanced inhibition of tumor growth. NaHCO3@Flip can also synergize with PD-1 antibody therapy. NaHCO3@Flip has the potential to serve as a therapeutic adjuvant for boosting chemoimmunotherapy by overcoming the ion-trapping effect and normalizing the tumor microenvironment.

Biogenesis and functional implications of extracellular vesicles in cancer metastasis

Extracellular vesicles (EVs) play a crucial role in the complex process of cancer metastasis by facilitating cellular communication and influencing the microenvironment to promote the spread and establishment of cancer cells in distant locations. This paper explores the process of EV biogenesis, explaining their various sources that range from endosomal compartments to plasma membrane shedding. It also discusses the complex mechanisms that control the sorting of cargo within EVs, determining their chemical makeup. We investigate the several functions of EVs in promoting the spread of cancer to other parts of the body. These functions include influencing the immune system, creating environments that support the formation of metastases before they occur, and aiding in the transformation of cells from an epithelial to a mesenchymal state. Moreover, we explore the practical consequences of EV cargo, such as nucleic acids, proteins, and lipids, in influencing the spread of cancer cells, from the beginning of invasion to the creation of secondary tumor sites. Examining recent progress in the field of EV-based diagnostics and treatments, we explore the potential of EVs as highly promising biomarkers for predicting the course of cancer and as targets for therapeutic intervention. This review aims to provide a complete understanding of the biology of EVs in the context of cancer metastasis. By unravelling the nuances of EV biology, it seeks to pave the way for new tactics in cancer detection, treatment, and management.

Cell blebbing novel therapeutic possibilities to counter metastasis

Cells constantly reshape there plasma membrane and cytoskeleton during physiological and pathological processes (Hagmann et al. in J Cell Biochem 73:488-499, 1999). Cell blebbing, the formation of bulges or protrusions on the cell membrane, is related to mechanical stress, changes in intracellular pressure, chemical signals, or genetic anomalies. These membrane bulges interfere with the force balance of actin filaments, microtubules, and intermediate filaments, the basic components of the cytoskeleton (Charras in J Microsc 231:466-478, 2008). In the past, these blebs with circular structures were considered apoptotic markers (Blaser et al. in Dev Cell 11:613-627, 2006). Cell blebbing activates phagocytes and promotes the rapid removal of intrinsic compartments. However, recent studies have revealed that blebbing is associated with dynamic cell reorganization and alters the movement of cells in-vivo and in-vitro (Charras and Paluch in Nat Rev Mol Cell Biol 9:730-736, 2008). During tumor progression, blebbing promotes invasion of cancer cells into blood, and lymphatic vessels, facilitating tumor progression and metastasis (Weems et al. in Nature 615:517-525, 2023). Blebbing is a dominant feature of tumor cells generally absent in normal cells. Restricting tumor blebbing reduces anoikis resistance (survival in suspension) (Weems et al. in Nature 615:517-525, 2023). Hence, therapeutic intervention with targeting blebbing could be highly selective for proliferating pro-metastatic tumor cells, providing a novel therapeutic pathway for tumor metastasis with minimal side effects. Here, we review the association between cell blebbing and tumor cells, to uncover new research directions and strategies for metastatic cancer therapy. Finaly, we aim to identify the druggable targets of metastatic cancer in relation to cell blebbing.

Nanocatalytic medicine enabled next-generation therapeutics for bacterial infections

The rapid rise of antibiotic-resistant strains and the persistence of biofilm-associated infections have significantly challenged global public health. Unfortunately, current clinical high-dose antibiotic regimens and combination therapies often fail to completely eradicate these infections, which can lead to adverse side effects and further drug resistance. Amidst this challenge, however, the burgeoning development in nanotechnology and nanomaterials brings hopes. This review provides a comprehensive summary of recent advancements in nanomaterials for treating bacterial infections. Firstly, the research progress of catalytic therapies in the field of antimicrobials is comprehensively discussed. Thereafter, we systematically discuss the strategies of nanomaterials for anti-bacterial infection therapies, including endogenous response catalytic therapy, exogenous stimulation catalytic therapy, and catalytic immunotherapy, in order to elucidate the mechanism of nanocatalytic anti-infections. Based on the current state of the art, we conclude with insights on the remaining challenges and future prospects in this rapidly emerging field.

BAP1 inactivation promotes lactate production by leveraging the subcellular localization of LDHA in melanoma

BRCA1-associated protein 1 (BAP1) acts as a tumor suppressor and can affect the cell cycle, tumor immunity, and cellular metabolism through multiple pathways. In melanoma, BAP1 mutations promote tumor cell glycolysis, leading to increased lactate production. The tumor microenvironment with high lactate levels is often associated with immunosuppression and tumor progression. The inhibitory effect of BAP1 on glycolysis has been found in a variety of tumors, but the specific mechanism by which BAP1 inhibits lactate production still needs to be elucidated. In this study, we show that BAP1 can interact directly with lactate dehydrogenase (LDHA), causing LDHA to accumulate in the nucleus. Conversely, BAP1 deletion leads to the accumulation of LDHA in the cytoplasm, catalyzing the production of lactate from pyruvate that results in increased lactate levels inside and outside the cell. By elucidating the interaction between BAP1 and LDHA and the subsequent effects on lactate production in melanoma cells, this work provides insights into the mechanism of BAP1-mediated metabolic regulation. Furthermore, it may provide novel directions for the clinical treatment of BAP1-mutant melanoma.

Synthetic and biological nanoparticles for cancer immunotherapy

Cancer is becoming the main public health problem globally. Conventional chemotherapy approaches are slowly being replaced or complemented by new therapies that avoid the loss of healthy tissue, limit off-targets, and eradicate cancer cells. Immunotherapy is nowadays an important strategy for cancer treatment, that uses the host's anti-tumor response by activating the immune system and increasing the effector cell number, while, minimizing cancer's immune-suppressor mechanisms. Its efficacy is still limited by poor therapeutic targeting, low immunogenicity, antigen presentation deficiency, impaired T-cell trafficking and infiltration, heterogeneous microenvironment, multiple immune checkpoints and unwanted side effects, which could benefit from improved delivery systems, able to release immunotherapeutic agents to tumor microenvironment and immune cells. Nanoparticles (NPs) for immunotherapy (Nano-IT), have a huge potential to solve these limitations. Natural and/or synthetic, targeted and/or stimuli-responsive nanoparticles can be used to deliver immunotherapeutic agents in their native conformations to the site of interest to enhance their antitumor activity. They can also be used as co-adjuvants that enhance the activity of IT effector cells. These nanoparticles can be engineered in the natural context of cell-derived extracellular vesicles (EVs) or exosomes or can be fully synthetic. In this review, a detailed SWOT analysis is done through the comparison of engineered-synthetic and naturaly-derived nanoparticles in terms of their current and future use in cancer immunotherapy.

Current hotspots and trends in cancer metabolic reprogramming: a scientometric analysis

Background

Metabolic reprogramming (MR) in cancer (CA) has been a focus of intense research in the recent two decades. This phenomenon has attracted great interest because it offers potential targets for cancer therapy. To capture the intellectual landscape of this field, we conducted a bibliometric analysis to assess the scientific output, major contributors, and trends in the MR/CA research.

Methods

We performed a systematic search using the Web of Science to retrieve articles published on MR of cancer from 2006 until 2023. The bibliometric tools such as Biblioshiny, VOSviewer, and Microsoft Excel were used to identify the most prolific authors, institutions, citation patterns, and keywords. We also used co-citation analysis to map the conceptual structure of the field and identify influential publications. Furthermore, we examined the literature by analyzing publication years, citations, and research impact factors.

Results

A total of 4,465 publications about MR/CA were retrieved. Publications on MR/CA increased rapidly from 2006 to 2023. Frontiers in Oncology published the most papers, while Cell Metabolism had the most citations. Highly cited papers were mainly published in Cancer Cell, Nature, Cell, Science and Cell Metabolism. China and the United States led the way in publications and contributed the most to MR/CA research. The University of Texas System, Chinese Academy of Sciences, and Fudan University were the most productive institutions. The profitable authors were Deberardinis Ralph J and Chiarugi Paola. The current topics included MR in tumorigenesis and progression of CA, MR of tumor cells and tumor microenvironment, the effect of MR on the CA treatment, the underlying mechanisms of MR (such as gene regulation, epigenetics, extracellular vesicles, and gut microbiota), and the modulation of MR. Some topics such as tumor microenvironment, lipid MR, circular RNA, long noncoding RNA, exosome, prognostic model, and immunotherapy may be the focus of MR/CA research in the next few years.

Conclusion

This study evaluated the global scientific output in the field of MR/CA research, analyzing its quantitative characteristics. It identified some significant and distinguished papers and compiled information regarding the current status and evolving trends of MR/CA research.

Disruption of the Physical Interaction Between Carbonic Anhydrase IX and the Monocarboxylate Transporter 4 Impacts Lactate Transport in Breast Cancer Cells

It has been previously established that breast cancer cells exhibit high expression of the monocarboxylate (lactate) transporters (MCT1 and/or MCT4) and carbonic anhydrase IX (CAIX) and form a functional metabolon for proton-coupled lactate export, thereby stabilizing intracellular pH. CD147 is the MCT accessory protein that facilitates the creation of the MCT/CAIX complex. This study describes how the small molecule Beta-Galactose 2C (BGal2C) blocks the physical and functional interaction between CAIX and either MCT1 or MCT4 in Xenopus oocytes, which reduces the rate of proton and lactate flux with an IC50 of ~90 nM. This value is similar to the Ki for inhibition of CAIX activity. Furthermore, it is shown that BGal2C blocks hypoxia-induced lactate transport in MDA-MB-231 and MCF-7 breast cancer cells, both of which express CAIX. As in oocytes, BGal2C interferes with the physical interaction between CAIX and MCTs in both cell types. Finally, X-ray crystallographic studies highlight unique interactions between BGal2C and a CAIX-mimic that are not observed within the CAII active site and which may underlie the strong specificity of BGal2C for CAIX. These studies demonstrate the utility of a novel sulfonamide in interfering with elevated proton and lactate flux, a hallmark of many solid tumors.

Mechanisms governing lineage plasticity and metabolic reprogramming in cancer

Dynamic alterations in cellular phenotypes during cancer progression are attributed to a phenomenon known as 'lineage plasticity'. This process is associated with therapeutic resistance and involves concurrent shifts in metabolic states that facilitate adaptation to various stressors inherent in malignant growth. Certain metabolites also serve as synthetic reservoirs for chromatin modification, thus linking metabolic states with epigenetic regulation. There remains a critical need to understand the mechanisms that converge on lineage plasticity and metabolic reprogramming to prevent the emergence of lethal disease. This review attempts to offer an overview of our current understanding of the interplay between metabolic reprogramming and lineage plasticity in the context of cancer, highlighting the intersecting drivers of cancer hallmarks, with an emphasis on solid tumors.

Metabolic adaptations in prostate cancer

Prostate cancer is one of the most commonly diagnosed cancers in men and is a major cause of cancer-related deaths worldwide. Among the molecular processes that contribute to this disease, the weight of metabolism has been placed under the limelight in recent years. Tumours exhibit metabolic adaptations to comply with their biosynthetic needs. However, metabolites also play an important role in supporting cell survival in challenging environments or remodelling the tumour microenvironment, thus being recognized as a hallmark in cancer. Prostate cancer is uniquely driven by androgen receptor signalling, and this knowledge has also influenced the paths of cancer metabolism research. This review provides a comprehensive perspective on the metabolic adaptations that support prostate cancer progression beyond androgen signalling, with a particular focus on tumour cell intrinsic and extrinsic pathways.

The missing link between cancer stem cells and immunotherapy

Cancer stem cells (CSCs) are cancer cells that can self-renew and give rise to tumors. The multipotency of CSCs enables the generation of diverse cancer cell types and their potential for differentiation and resilience against chemotherapy and radiation. Additionally, specific biomarkers have been identified for them, such as CD24, CD34, CD44, CD47, CD90, and CD133. The CSC model suggests that a subset of CSCs within tumors is responsible for tumor growth. The tumor microenvironment (TME), including fibroblasts, immune cells, adipocytes, endothelial cells, neuroendocrine (NE) cells, extracellular matrix (ECM), and extracellular vesicles, has a part in shielding CSCs from the host immune response as well as protecting them against anticancer drugs. The regulation of cancer stem cell plasticity by cancer-associated fibroblasts (CAFs) occurs through specific signaling pathways that differ among various types of cancer, utilizing the IGF-II/IGF1R, FAK, and c-Met/FRA1/HEY1 signaling pathways. Due to the intricate dynamics of CSC proliferation, controlling their growth necessitates innovative approaches and much more research. Our current review speculates an outline of how the TME safeguards stem cells, their interaction with CSCs, and the involvement of the immune and inflammatory systems in CSC differentiation and maintenance. Several technologies have the ability to identify CSCs; however, each approach has limitations. We discuss how these methods can aid in recognizing CSCs in several cancer types, comprising brain, breast, liver, stomach, and colon cancer. Furthermore, we explore different immunotherapeutic strategies targeting CSCs, including stimulating cancer-specific T cells, modifying immunosuppressive TMEs, and antibody-mediated therapy targeting CSC markers.

Circadian rhythms of macrophages are altered by the acidic tumor microenvironment

Tumor-associated macrophages (TAMs) are prime therapeutic targets due to their pro-tumorigenic functions, but varying efficacy of macrophage-targeting therapies highlights our incomplete understanding of how macrophages are regulated within the tumor microenvironment (TME). The circadian clock is a key regulator of macrophage function, but how circadian rhythms of macrophages are influenced by the TME remains unknown. Here, we show that conditions associated with the TME such as polarizing stimuli, acidic pH, and lactate can alter circadian rhythms in macrophages. While cyclic AMP (cAMP) has been reported to play a role in macrophage response to acidic pH, our results indicate pH-driven changes in circadian rhythms are not mediated solely by cAMP signaling. Remarkably, circadian disorder of TAMs was revealed by clock correlation distance analysis. Our data suggest that heterogeneity in circadian rhythms within the TAM population level may underlie this circadian disorder. Finally, we report that circadian regulation of macrophages suppresses tumor growth in a murine model of pancreatic cancer. Our work demonstrates a novel mechanism by which the TME influences macrophage biology through modulation of circadian rhythms.

Microenvironmental alkalization promotes the therapeutic effects of MSLN-CAR-T cells

Triple-negative breast cancer (TNBC) is characterized by high invasion, prone metastasis, frequent recurrence and poor prognosis. Unfortunately, the curative effects of current clinical therapies, including surgery, radiotherapy, chemotherapy and immunotherapy, are still limited in patients with TNBC. In this study, we showed that the heterogeneous expression at the protein level and subcellular location of mesothelin (MSLN), a potential target for chimeric antigen receptor-T (CAR-T) cell therapy in TNBC, which is caused by acidification of the tumor microenvironment, may be the main obstacle to therapeutic efficacy. Alkalization culture or sodium bicarbonate administration significantly promoted the membrane expression of MSLN and enhanced the killing efficiency of MSLN-CAR-T cells both in vitro and in vivo, and the same results were also obtained in other cancers with high MSLN expression, such as pancreatic and ovarian cancers. Moreover, mechanistic exploration revealed that the attenuation of autophagy-lysosome function caused by microenvironmental alkalization inhibited the degradation of MSLN. Hence, alkalization of the microenvironment improves the consistency and high expression of the target antigen MSLN and constitutes a routine method for treating diverse solid cancers via MSLN-CAR-T cells.

Overcoming Barriers in Photodynamic Therapy Harnessing Nanogenerators Strategies

Photodynamic therapy (PDT) represents a targeted approach for cancer treatment that employs light and photosensitizers (PSs) to induce the generation of reactive oxygen species (ROS). However, PDT faces obstacles including insufficient PS localization, limited light penetration, and treatment resistance. A potential solution lies in nanogenerators (NGs), which function as self-powered systems capable of generating electrical energy. Recent progress in piezoelectric and triboelectric NGs showcases promising applications in cancer research and drug delivery. Integration of NGs with PDT holds the promise of enhancing treatment efficacy by ensuring sustained PS illumination, enabling direct electrical control of cancer cells, and facilitating improved drug administration. This comprehensive review aims to augment our comprehension of PDT principles, explore associated challenges, and underscore the transformative capacity of NGs in conjunction with PDT. By harnessing NG technology alongside PDT, significant advancement in cancer treatment can be realized. Herein, we present the principal findings and conclusions of this study, offering valuable insights into the integration of NGs to overcome barriers in PDT.

Hydrogen peroxide responsive theranostics for cancer-selective activation of DNA alkylators and real-time fluorescence monitoring in living cells

Triple negative breast cancer (TNBC) is a notoriously difficult disease to treat, and many of the existing TNBC chemotherapeutics lack tumor selectivity and the capability for simultaneously visualizing and monitoring their own activity in the biological context. However, TNBC cells have been known to generate high levels of reactive oxygen species (ROS), such as hydrogen peroxide (H2O2). To this end, three novel small molecule theranostics 1a, 1c, and 2 consisting of both H2O2-responsive nitrogen mustard prodrug and profluorophore character have been designed, synthesized, and evaluated as targeted cancer therapeutics and bioimaging agents. The three theranostics comprise of boronate esters that deactivate nitrogen mustard functional groups and fluorophores but allow their selective activation through H2O2-specific oxidative deboronation for the release of the active drug and fluorophore. The three theranostics demonstrated H2O2-inducible DNA-alkylating capability and fluorescence turn-on properties in addition to selective anticancer activity. They are particularly effective in killing TNBC MDA-MB-468 cells with high H2O2 level while safe to normal epithelial MCF-10A cell. The conjugated boron-masked fluorophores in 1c and 2 are highly responsive towards H2O2, which enabled tracking of the theranostics in living cellular mitochondria and nucleus organelles. The three theranostics 1a, 1c, and 2 are capable of both selective release of the active drug to take effect in H2O2-rich cancer sites and simultaneously monitoring its activity. This single molecule system is of utmost importance to understand the function, efficacy, and mechanism of the H2O2-activated prodrugs and theranostics within the living recipient.