A substantial portion of patients experience radioresistance, which impedes clinical benefit. The radiation-induced 'protumor' immune response is previously demonstrated to limit antitumor efficacy. However, the detailed mechanism remains to be explored. In this study, we observe CXCR5+ monocytes are enriched in tumor upon radiation. CXCR5 expression on monocytes in host is induced by tumor-derived VEGF through PI3K/mTOR/HIF-1α axis. Local radiation enhances CXCL13 expression from tumor cells, a specific ligand of CXCR5, which leads to the recruitment of CXCR5+ monocytes. Tumor-infiltrating CXCR5+ monocytes induce radioresistance by inhibiting CD8+ T cells through PD-1/PD-L1 interaction. Moreover, radiation-induced GM-CSF promotes the differentiation of CXCR5+ monocytes toward M2-like macrophages. In contrast, inhibiting VEGFR signaling, neutralizing CXCL13 and GM-CSF, or blocking PD-L1 facilitates radiation-induced tumor control by abrogating CXCR5+ monocyte-mediated immunosuppression. Furthermore, the CXCR5+ and CD14+ populations are increased in patients with cancer following radiotherapy. Monocyte is increased in the peripheral blood of patients with progressive disease following radiotherapy. These findings suggest potential strategies for blocking the CXCR5/CXCL13 axis to improve radiotherapy efficacy.

Tumor metastasis is the primary cause of cancer treatment failure and mortality. Pregnant patients with cancer sometimes experience a poor prognosis and accelerated disease progression, yet the underlying mechanisms remain poorly understood. Here we show that pregnancy enhances tumor metastasis in female mice by elevating adenosine levels, which drives pre-metastatic niche remodeling. Myeloid cells in placental and uterine tissues exhibit increased expression of adenosine-generating enzymes, CD39 and CD73. The accumulated adenosine recruits neutrophils into the tissues of the pre-metastatic microenvironment and upregulates PD-L1 expression on these cells through the cAMP-PKA-NF-κB pathway, thereby suppressing CD8+ T cell function. Consistent with murine models, pregnant women exhibit elevated adenosine levels and increased PD-L1+ neutrophils in peripheral blood, hindering human T cell activation. Inhibiting the adenosine-PD-L1+ neutrophil axis reverses, at least partially, pregnancy-accelerated metastasis without affecting fetal development. These findings shed light on the mechanism of tumor metastasis mice during pregnancy and suggest potential therapeutic targets for treating cancers in pregnant patients.

The NAD(H)/NADP(H) ratio is essential for maintaining cellular redox homeostasis. NAD kinase (NADK) is the sole cytosolic enzyme responsible for converting NAD+ to NADP+. Dysregulation of NADK has been linked to aging and cancer; however, the underlying regulatory mechanisms remain poorly understood. Here, we show that NADP+ synthesis is markedly suppressed in mice fed a high-fat diet. Mechanistically, NADK undergoes PRMT6-mediated arginine methylation at residues R39, R41, and R45, which inhibits its kinase activity and reduces NADP+ production. Mutations at these sites enhance cancer cell proliferation and tumor growth. PRMT6-dependent methylation antagonizes Akt-mediated phosphorylation to inhibit NADK activity by promoting an autoinhibitory function within its N-terminal region, thereby inhibiting NADP+ synthesis. In addition, PRMT6 can suppress NADK activity in a phosphorylation-independent manner. NADK methylation is further upregulated by the RB1/E2F pathway in response to a high-fat diet. In hepatocellular carcinoma, reduced NADK methylation elevates NADP+ levels and facilitates tumor progression. Collectively, these findings elucidate a regulatory mechanism governing NAD(H)/NADP(H) homeostasis and identify the PRMT6–NADK axis as a critical mediator of cellular adaptation to high-fat diets and increased adiposity.

Radiotherapy is a cornerstone of cancer therapy but is often undermined by tumor radioresistance arising from insufficient generation of reactive oxygen species (ROS) and limited DNA damage. Cuproptosis-a newly identified form of copper-dependent cell death-offers an innovative, yet untapped, approach to enhance radiosensitivity. Here, we report a first-of-its-kind copper-doped metal-organic framework nanoplatform, based on a ZIF-8 framework and loaded with the copper ionophore elesclomol, to concurrently induce cuproptosis and amplify radiotherapy. This nanoplatform (Cu-MOF@ELS) efficiently shuttles copper into cancer cell mitochondria, triggering excessive reactive oxygen species (ROS) production and mitochondrial dysfunction that synergize with radiation to promote extensive DNA damage. We demonstrate that Cu-MOF@ELS strongly induces cuproptosis in tumor cells and significantly boosts radiotherapeutic efficacy in vitro and in vivo, with treated mice showing pronounced tumor regression and minimal systemic toxicity. Our work pioneers a novel therapeutic paradigm by integrating cuproptosis induction with radiotherapy, establishing Cu-MOF@ELS as a groundbreaking radiosensitizer that exploits metabolic cell-death mechanisms to overcome tumor radioresistance.

Cognitive impairment is a common side effect of docetaxel (DTX)-based chemotherapy. The novel neuroprotective agent edaravone dexborneol (ED) was found to alleviate the adverse phenotype caused by DTX. However, the underlying mechanism remains unexplored. By analyzing mRNA-sequencing data, we noticed that the expression of S100 calcium-binding protein A11 (S100A11), a protector of the nervous system, was decreased in DTX-treated rats with cognitive damage, but ED administration reversed the trend. Therefore, we speculated that S100A11 might be involved in the protective effects of ED on DTX-induced cognitive impairment. Sprague-Dawley rats were intraperitoneally injected with DTX to induce cognitive impairment, followed by intraperitoneal injection of ED after DTX induction. The results showed that ED treatment mitigated cognitive impairment caused by DTX. Next, adenoviruses carrying sequences encoding S100A11 were given to rats receiving DTX treatment. S100A11 overexpression alleviated cognitive dysfunction of DTX-treated rats, as evidenced by the decreased escape latency and swimming distance, and the increased number of platform crossings. Mechanically, S100A11 overexpression inhibited neuronal apoptosis by inactivating the MAPK signaling pathway. Further rescue experiments showed that S100A11 knockdown reversed the defensive role of ED in DTX-induced neuronal damage. In conclusion, ED ameliorates cognitive dysfunction caused by DTX by upregulating the S100A11 expression and subsequently inactivating the MAPK signaling pathway.

Traditional cancer imaging modalities cannot achieve ideal diagnostic results. Fluorescence imaging is an emerging modality for tumor imaging because of its high selectivity and sensitivity. However, conventional imaging agents have some drawbacks, including significant photobleaching, low fluorescence quantum yield, and inadequate targeting specificity. Therefore, there is an urgent need for the development of new imaging agents. Viologen derivatives have been widely used in the optical field owing to their excellent water solubility and good optical properties. However, because of its propensity to readily obtain electrons and form free radicals, its biological toxicity is significant, restricting its further application in the field of biological staining. To solve these problems, this study incorporated phenyl viologen as the primary fluorescent structure, which is capable of directly forming a quinone structure in a single step, thereby mitigating the impact of free radicals on cells. Furthermore, the introduction of biotin further enhanced the targeting of the imaging agent, ensuring that it was delivered more precisely to the desired cellular locations. This dual approach not only minimizes the harmful effects of free radicals but also improves the specificity and efficiency of cellular imaging. Experimental results demonstrate that the developer exhibits high photostability, excellent biosafety, and outstanding biocompatibility. This study investigated the application of cationic viologen derivatives in living cell imaging, laying a foundation for the advancement of cationic viologen derivatives in the biological field.

PURPOSE:Combining radiotherapy with androgen deprivation therapy (ADT) is recommended for localized prostate cancer. However, the time required for significant therapeutic benefits is not well quantified. This study aims to determine the time to benefit (TTB) of ADT in these patients. METHODS:We systematically searched PubMed, Scopus, Embase, and Cochrane databases for randomized clinical trials that compared definitive radiotherapy with or without ADT in localized prostate cancer. The primary end point was all-cause mortality. We reconstructed individual patient survival data and calculated TTB using Weibull survival curves, the frequentist method, and the delta method. RESULTS:Eight trials with 6,839 participants were included, with more than 80% of them being patients with intermediate- or high-risk prostate cancer. For patients adding ADT to radiotherapy, it took 7.46 (95% CI, 2.53 to 22.00), 11.36 (95% CI, 4.61 to 28.03), 19.97 (95% CI, 10.03 to 39.78), and 30.90 months (95% CI, 17.90 to 53.36) to prevent one case of all-cause mortality per 1,000, 500, 200, and 100 patients, respectively. To prevent one case of prostate cancer-specific mortality, local progression, distant metastasis, and biochemical failure per 100 patients, it required 40.58 (95% CI, 30.20 to 54.53), 10.92 (95% CI, 6.03 to 19.79), 11.36 (95% CI, 6.55 to 19.69), and 7.80 months (95% CI, 5.14 to 11.83), respectively. CONCLUSION:Adding ADT to radiotherapy provides rapid clinical benefits for patients with intermediate- and high-risk localized prostate cancer. Patients with an expected lifespan over 30 months may benefit from this treatment.

Introduction XPO1 plays a crucial role in the nuclear export machinery, making it an attractive target for inhibiting nuclear-cytoplasmic transport in melanoma, where its overexpression is linked to unfavorable prognosis. However, XPO1 monotherapy has not demonstrated sufficient efficacy to be considered a first-line treatment option for melanoma. Objectives This research aimed to delve into the resistance mechanism of XPO1-targeting therapy in melanoma and fabricate a proteinoid microsphere which could target XPO1 and β-catenin to maximize the effect of XPO1 inhibitors. Methods Transcriptome sequencing was used to analyze the effects of XPO1 interference on the signaling pathways of melanoma. Nuclear-cytoplasmic protein separation, co-immunoprecipitation, and confocal microscopic analyses were conducted to clarify the resistance mechanism of XPO1 targeting therapy. A proteinoid microsphere named XPinβ was developed by co-assembling a specially designed XPO1 antagonistic peptide (XPin) and a β-catenin antagonist (Carnosic acid/CA). Cell model, mouse allograft and patient-derived xenograft (PDX) models were used to evaluate the antitumor effect of XPinβ. Results In our study, inhibition of XPO1 led to the nuclear accumulation of β-catenin, altered the nuclear-cytoplasmic localization of APC, and activated the Wnt/β-catenin signaling pathway. XPinβ was efficiently internalized into melanoma cells via macropinocytosis, achieving simultaneous inhibition of both XPO1 and β-catenin. As expected, XPinβ demonstrated robust anti-tumor efficacy in an allograft melanoma mouse model, with significantly superior therapeutic effects compared to monotherapy targeting XPO1 or CA treatment alone. Moreover, XPinβ effectively inhibited growth of patient-derived xenograft (PDX) tumors overexpressing XPO1, outperforming both CA and the commercially available XPO1 inhibitor KPT-330. Most importantly, XPinβ significantly suppressed pulmonary metastasis of melanoma while maintaining excellent biosafety. Conclusions This study demonstrates the enhanced efficacy of XPO1-targeted therapy through the inhibition of the Wnt/β-catenin signaling pathway and introduces XPinβ, a proteinoid microsphere with promising clinical translational potential for dual targeting therapy against melanoma involving both XPO1 and β-catenin.

Introduction Ferroptosis is an iron-dependent form of cell death triggered by the excessive accumulation of lipid peroxides. Understanding the regulatory mechanisms of ferroptosis and developing strategies to target this process hold significant clinical applications in tumor therapy. Objective Our study aims to search for novel candidate genes involved in the regulation of ferroptosis and to investigate their mechanism of action in ferroptosis and tumor therapy. Methods We employed a CRISPR-Cas9 library to perform a genome-wide screen under ferroptosis inducer treatment conditions, revealing Scavenger Receptor Class B Member 1(SCARB1) as a novel candidate gene involved in ferroptosis regulation. Subsequently, lipidomic analyses, metabolic interventions, and relevant cellular experimental analyses were performed to elucidate the role of SCARB1 in ferroptosis, lipid peroxidation, and tumor therapy. Results Our study confirmed that SCARB1 significantly inhibits ferroptosis and lipid peroxidation induced by ferroptosis inducers. Mechanistically, SCARB1 inhibits ferroptosis through the regulation of cholesterol metabolism, and the upregulation of CoQ10 level is demonstrated to mediate the suppression of ferroptosis by SCARB1 after lipidomic analysis and metabolic intervention. Interestingly, SCARB1 exerts a tumor suppressive effect regarding tumor growth, migration and invasion, which is possibly independent of ferroptosis regulation. However, SCARB1 promotes radioresistance through the upregulation of cholesterol metabolism and inhibition of ferroptosis, while the combination of ferroptosis inducers can overcome radioresistance in tumor cells with high SCARB1 expression. Conclusion This study establishes a theoretical foundation for the regulation of ferroptosis by SCARB1 and highlights the potential of targeting lipid metabolism to overcome radioresistance in cancer therapy. The identification of SCARB1 as a key player in ferroptosis and its dual role in tumor suppression and radioresistance provides new avenues for therapeutic intervention in cancer treatment.

Reactive oxygen species (ROS) play a crucial role in lipid peroxidation and the initiation of ferroptosis, markedly affecting chemotherapeutic drug resistance. However, the mechanisms by which ROS function and are sensed remain poorly understood. In this study, we identified O-GlcNAc transferase (OGT), a key enzyme in protein O-GlcNAcylation, as a sensor for ROS during ferroptosis. The ROS-induced oxidation of OGT at C845 in its catalytic domain activates the enzyme. Once activated, OGT O-GlcNAcylates FOXK2, enhancing its interaction with importin α, which facilitates FOXK2's nuclear translocation and binding to the SLC7A11 promoter region. This, in turn, boosts SLC7A11 transcription, thereby inhibiting ferroptosis. The elevated OGT-FOXK2-SLC7A11 axis contributes to tumorigenesis and resistance to chemoradiotherapy in hepatocellular carcinoma (HCC). Our findings elucidate a ROS-induced oxidation-O-GlcNAcylation cascade that integrates ROS signalling, O-GlcNAcylation, FOXK2-mediated SLC7A11 transcription and resistance to both ferroptosis and chemoradiotherapy.

KRAS is a prominent oncogene mutated in a large number of human malignancies, particularly in pancreatic, colorectal, and lung tumors. We demonstrate here that KRAS, including its various activating mutants, is subjected to ubiquitin-mediated proteasomal degradation in cancer cells. Through an siRNA-based screening of deubiquitinases, we identified USP25 as a deubiquitinase for KRAS. Depleting USP25 expression increases ubiquitination and proteasomal degradation of KRAS, leading to the suppression of its oncogenic activity. We further show that USP25 inhibitors we have discovered are capable of destabilizing KRAS in cancer cells and are efficacious in blocking tumor xenograft growth in mice. These findings provide evidence supporting the notion that targeting the deubiquitinase USP25 can effectively, albeit indirectly, suppress KRAS and potentially aid in the treatment of tumors driven by KRAS-activating mutations.

Platinum-based therapy is an integral part of the standard treatment for ovarian cancer. However, despite extensive research spanning several decades, the identification of dependable predictive biomarkers for platinum response in clinical practice has proven to be a formidable challenge. Recently, the development of single-cell technology has enabled more precise investigations into the heterogeneity of cancer. In this study, we isolated cancer cells from the single-cell transcriptomic data of platinum-sensitive and platinum-resistant patients with ovarian cancer. Differential gene analysis of platinum-sensitive and platinum-resistant cancer cells revealed that several of the differentially expressed genes had previously been reported in other studies to be associated with platinum resistant. Gene set enrichment analysis revealed the up-regulation of pathways involved in processes such as autophagy, cell cycle regulation, and DNA damage repair, which are known to promote platinum resistance in ovarian cancer. Based on these findings, we hypothesized that these differentially expressed genes could be used to predict the response of ovarian cancer patients to platinum-based chemotherapy. To validate this hypothesis, we explored 7 different machine learning models for predicting platinum chemotherapy response at varying feature gene counts. Ultimately, the random forest model performed the best, with 5 genes (PAX2, TFPI2, APOA1, ADIRF and CRISP3) and achieve an AUC of 0.993 in test cohort and 0.989 in GSE63885 independent validation cohorts. We named this model GPPS (Genes to Predict Platinum response Signature). Furthermore, we discovered that the GPPS model can also predict patient prognosis.

NADK is the sole cytosolic enzyme responsible for synthesizing NADP+ from NAD+ within cells. The homeostasis of NAD+/NADP+ is controlled by NADK, usually dysregulated in various cancers, yet the precise underlying regulatory mechanisms remain largely unknown. In this study, we discover that PRMT6 methylates NADK at R39, R41, and R45, resulting in the suppression of NADK kinase activity and NADP+ synthesis. Mutations of these sites promote cancer cell proliferation and tumor growth. PRMT6-mediated methylation of NADK coordinates with Akt-mediated phosphorylation to regulate NADK, which stimulates its activity to increase NADP+ production through relief of an autoinhibitory function inherent to its amino terminus. PRMT6 also inhibits NADK activity in a phosphorylation-independent manner. Furthermore, NADK methylation is upregulated by RB1/E2F pathway in high-fat diet mice. Downregulation of NADK methylation in HCC enhances NADP+ production to promote cancer development. Our findings illuminate the molecular regulatory mechanisms governing NAD+/NADP+ homeostasis, suggesting that the PRMT6-NADK axis emerges as a direct player in high energy state. Furthermore, our research suggests potential therapeutic targets through chemical and genetic interventions. ### Competing Interest Statement The authors have declared no competing interest.

The multidrug resistance-associated protein (MRP) ABCC4 facilitates substrate transport across the cytoplasmic membrane, crucial for normal physiology and mediating multidrug resistance in tumor cells. Despite intensive studies on MRPs, ABCC4's transport mechanism remains incompletely understood. In this study, we unveiled an inward-open conformation with an ATP bound to degenerate NBD1. Additionally, we captured the structure with both ATP and substrate co-bound in the inward-open state. Our findings uncover the asymmetric ATP binding in ABCC4 and provide insights into substrate binding and transport mechanisms. ATP binding to NBD1 is parallel to substrate binding to ABCC4, and is a prerequisite for ATP-bound NBD2-induced global conformational changes. Our findings shed new light on targeting ABCC4 in combination with anticancer therapy.

BackgroundCell fate and microenvironmental changes resulting from aberrant expression of specific proteins in tumors are one of the major causes of inadequate anti-tumor immune response and poor prognosis in head and neck cancer (HNC). Eukaryotic initiation factor 3C (eIF3c) has emerged as a promising therapeutic target for HNC due to its ability to regulate protein expression levels in tumor cells, but its drug development is difficult to achieve by targeting traditional protein-protein interactions. siRNA has emerged as a highly promising modality for drug development targeting eIF3c, while its application is hindered by challenges pertaining to inadequate stability and insufficient concentration specifically within tumor sites.MethodWe employed a method to convert flexible siRNAs into stable and biologically active infinite Auric-sulfhydryl coordination supramolecular siRNAs (IacsRNAs). Through coordinated self-assembly, we successfully transformed eIF3C siRNAs into the carrier-free HNC nanotherapeutic agent Iacs-eif3c-RNA. The efficacy of this agent was evaluated in vivo using HNC xenograft models, demonstrating promising antitumor effects.ResultsIacs-eif3c-RNA demonstrated the ability to overcome the pharmacological obstacle associated with targeting eIF3C, resulting in a significant reduction in eIF3C expression within tumor tissues, as well as effective tumor cell proliferating suppression and apoptosis promotion. In comparison to monotherapy utilizing the chemotherapeutic agent cisplatin, Iacs-eif3c-RNA exhibited superior anti-tumor efficacy and favorable biosafety.ConclusionThe utilization of Iacs-eif3c-RNA as a carrier-free nanotherapeutic agent presents a promising and innovative approach for addressing HNC treating challenges. Moreover, this strategy demonstrates potential for the translation of therapeutic siRNAs into clinical drugs, extending its applicability to the treatment of other cancers and various diseases.

Gastric cancer is the third leading cause of cancer-related death worldwide, with relapse and metastasis being major contributors to the mortality. Circular RNAs (circRNAs) have been at the center of several researches and some circRNAs have been indicated to be involved in gastric cancer as sponges. Nevertheless, the mechanism underlying the function of circRNA remains largely unclear. Therefore, this study was conducted with the main objective of screening the associated circRNA in gastric cancer and exploring its mechanism. Expression of hsa_circRNA_0009172 was validated in gastric cancer tissues and cell lines after the correlation between hsa_circRNA_0009172 and prognosis was determined. Moreover, the binding site between miR-485-3p and hsa_circRNA_0009172 or NTRK3 was verified using dual luciferase assay and RNA pull down. Function-gain and -loss experiments were performed for the purpose of detecting the effect of hsa_circRNA_0009172 in vivo and in vitro as well as its mechanism with microRNA (miRNA)-485-3p and NTRK3 in gastric cancer. The hsa_circRNA_0009172 expression was downregulated in gastric cancer tissues and cell lines, indicating a positive association with patient prognosis. Functionally, hsa_circ_0009172 overexpression inhibited proliferative, invasive and migrative potential of gastric cancer cells as well as epithelial-mesenchymal transition (EMT)-related proteins by sponging miR-485-3p to inhibit NTRK3, while miR-485-3p overexpression could reverse the inhibitory effect of hsa_circ_0009172 on gastric cancer. Furthermore, either up-regulation of hsa_circ_0009172 or down-regulation of miR-485-3p led to the suppression of xenograft tumor growth in nude mice. In conclusion, hsa_circ_0009172 serves as a tumor suppressor in gastric cancer by targeting miR-485-3p/NTRK3 axis.

Over half of cancer patients are subjected to radiotherapy, but owing to the deficient amount of reactive oxygen radicals (ROS) and DNA double-strand breaks (DSBs), a fair number of them suffer from radiotherapy resistance and the subsequent short-term survival opportunity. To overcome it, many successes have been achieved in radiosensitizer discovery using physical strategy and/or biological strategy, but significant challenges remain regarding developing clinically translational radiosensitizers. Herein, a peptide-Au(I) infinite coordination supermolecule termed PAICS is developed that combined both physical and biological radiosensitization and possessed pharmaceutical characteristics including adequate circulatory stability, controllable drug release, tumor-prioritized accumulation, and the favorable body eliminability. As expected, monovalent gold ion endowed this supermolecule with high X-ray absorption and the subsequent radiosensitization. Furthermore, a peptide targeting CRM1, is assembled into the supermolecule, which successfully activates p53 and apoptosis pathway, thereby further sensitizing radiotherapy. As a result, PAICS showed superior ability for radiotherapy sensitization in vivo and maintained a favorable safety profile. Thus, the PAICS reported here will offer a feasible solution to simultaneously overcome both the pharmaceutical obstacles of physical and biological radiosensitizers and will enable the development of a class of nanomedicines for tumor radiotherapy sensitization.