BACKGROUND:Tumor-associated macrophages (TAMs) are key drivers of the immunosuppressive tumor microenvironment (TME), thereby limiting the efficacy of immune checkpoint inhibitors (ICIs). However, the underlying mechanisms remain unclear. METHODS:Both genetic (Akr1b3 knockout) and pharmacologic (epalrestat) approaches were employed to examine the impact of Aldo-keto reductase family 1 member B1 (AKR1B1) inhibition on TAMs and T-cell function in vitro and in vivo. Mechanistic insights were obtained through RNA sequencing, flow cytometry, immunofluorescence staining, and co-culture assays. To assess therapeutic relevance, 4T1 breast cancer and LLC lung carcinoma mouse models were used to evaluate the effects of epalrestat on tumor growth, immune infiltration, and T-cell responses. Clinical relevance was validated in patient cohorts with triple-negative breast cancer (TNBC) and lung adenocarcinoma (LUAD). RESULTS:AKR1B1 is highly expressed in TAMs and correlates with CD8+ T-cell dysfunction. Targeting AKR1B1 enhances antitumor immunity by reprogramming TAMs. Mechanistically, AKR1B1 modulates macrophage metabolism via the glutathione/reactive oxygen species axis, suppressing nuclear factor κB activation and downregulating C-C motif chemokine ligand 5 (CCL5) production, thereby inducing CD8+ T-cell dysfunction and establishing an immunosuppressive TME. Inhibition of AKR1B1, either by gene knockout or selective pharmacologic blockade, reprograms TAMs toward an immunostimulatory phenotype, increases CCL5-CCR5 (C-C motif chemokine receptor 5) signaling, restores CD8+T cell effector function, and strengthens antitumor immunity. Clinically, high AKR1B1 expression is associated with poor prognosis and immune suppression in TNBC and LUAD. Notably, targeting AKR1B1 improves responses to ICIs in both breast and lung cancer models. CONCLUSIONS:AKR1B1 as a critical regulator of TAM-mediated immunosuppression and highlight its therapeutic potential to enhance the efficacy of ICIs.

Targeting glucose metabolism has long been pursued as an anticancer strategy, yet its clinical translation remains challenging. Achieving therapeutic selectivity requires identifying actionable metabolic distinctions between different malignant traits. Here, we uncover a noncanonical, lactate-independent glucose metabolic pathway facilitated by the glucose transporter 6 (GLUT6), which confers targeted therapy resistance in lung cancer. Downstream, GLUT6 promotes glucose influx and diversion toward methylglyoxal production, leading to kelch-like ECH-associated protein 1 (KEAP1) dimerization and nuclear factor erythroid 2-related factor 2 (NRF2) pathway activation, driving resistance. Upstream, GLUT6 expression is transcriptionally upregulated by therapy-induced MYC associated zinc finger protein (MAZ) activation. Targeting GLUT6 prevents and overcomes EGFR and KRAS inhibitors resistance. Moreover, the MAZ-GLUT6-NRF2 axis correlates with clinical treatment response and relapse. The preferential reliance on GLUT6-a noncanonical transporter with minimal systemic homeostasis perturbation-highlights its promise as a target for overcoming resistance and revitalizing glucose metabolism-based anticancer strategies.

Methicillin-resistant Staphylococcus aureus (MRSA) is difficult to treat because its tightly regulated virulence network and robust biofilm formation reduce antibiotic efficacy and promote resistance. We developed a tetrahedral framework nucleic acid nanoplatform that delivers dicumarol, a small-molecule inhibitor of the virulence regulator SaeR. Biophysical and biochemical assays showed that dicumarol binds SaeR with high affinity and interferes with the SaeR-DNA interaction. At sub-MIC concentrations that do not inhibit planktonic growth, dicumarol reduced saePQRS transcription and lowered the expression of SaeR-controlled virulence genes. After loading dicumarol into the tetrahedral framework nucleic acid carrier, we obtained a stable nanoconjugate with high loading efficiency, sustained release in buffer and synovial fluid mimicking media, and efficient uptake by both bacteria and chondrocytes. Compared with the same dose of free dicumarol, the nanoconjugate produced stronger inhibition of SaeR protein expression, hemolysis, biofilm formation and virulence factor production. In S. aureus infected ATDC5 cells, the nanoconjugate reduced the intracellular bacterial burden, decreased reactive oxygen species accumulation, limited NF-kappa B activation and proinflammatory cytokine release, and lowered the expression of cartilage-degrading genes. In Galleria mellonella and rat pyogenic arthritis models, it reduced bacterial load, alleviated joint swelling, preserved bone microarchitecture and cartilage integrity, and decreased MMP-13 expression together with synovial NF-kappa B signaling. These results support the tetrahedral framework nucleic acid dicumarol system as a SaeR-targeted nanotherapeutic that combines antivirulence activity with host protective immunomodulation and may serve as an effective complement to conventional antibiotic therapy for refractory MRSA infection.

Lung adenocarcinoma (LUAD) with epidermal growth factor receptor (EGFR) mutations is prevalent in East Asian NSCLC patients and responds initially to EGFR-tyrosine kinase inhibitors (EGFR-TKIs), but resistance inevitably develops. This study identifies ATP-binding cassette subfamily A member 3 (ABCA3) as a key protein involved in tumor progression and TKI resistance in EGFR-mutant cancers. ABCA3 was significantly upregulated in EGFR-mutant LUAD cells compared to WT, promoting cell viability, proliferation, migration, and clonogenicity, while suppressing apoptosis. Mechanistic analyses revealed that ABCA3 enhanced cholesterol uptake and activated the PI3K/AKT/mTOR pathway, contributing to tumor growth. Moreover, the transcription factor SP1 was found to induce ABCA3 expression, especially following EGFR-TKI treatment. ABCA3 was markedly elevated in EGFR-TKI-resistant cell line, and its inhibition restored drug sensitivity. These findings suggest that ABCA3 plays a central role in mediating both tumor progression and resistance in EGFR-mutant LUAD. Targeting ABCA3 may represent a promising strategy to suppress tumor growth and overcome EGFR-TKI resistance, providing a novel therapeutic avenue for patients with EGFR-mutated non-small cell lung cancer.

Breast cancer is prevalent and deadly, affecting women worldwide. Increasing research suggests that lysine lactylation (KLA) and DNA damage repair (DDR) play critical roles in tumor progression and that KLA and DDR are interconnected, as KLA can modulate DDR protein function, thereby influencing genome stability and drug response, while DDR signaling can reciprocally reshape lactate metabolism and KLA activity. In this study, we developed a novel prognostic gene signature (KLA and DDR index, KLDRI) based on KLA- and DDR-related genes. Model genes (PGK1, MORF4L2, RAD54B, RPA3, CCND2) were generated via LASSO-Cox regression. Patients were stratified into high- and low-risk groups according to KLDRI, the robust prognostic value of which was demonstrated via survival and validation analyses in the TCGA cohort and the METABRIC and GSE96058 cohorts, respectively. Tumor microenvironment analysis indicated an immunologically suppressed phenotype in high-risk patients, whereas low-risk patients exhibited an immune-inflamed microenvironment. Drug sensitivity analysis indicated reduced sensitivity to multiple chemotherapy and targeted therapy drugs in the high-risk group. Single-cell transcriptomic analysis revealed differential gene expression patterns between risk groups. A prognostic nomogram based on KLDRI was developed to predict overall survival. Furthermore, functional experiments demonstrated that RPA3 knockdown suppressed cancer cell proliferation and migration, sensitized cells to cisplatin treatment, and reduced global lactylation, which may serve as a novel biomarker and potential therapeutic target. These findings enhance our understanding of the interplay between KLA, DDR, and breast cancer progression, facilitating the development of personalized therapeutic strategies.

The clinical effect of KRAS G12C inhibitors (G12Ci) as monotherapy is poor, prompting the development of combination treatment strategies. Here, we demonstrate that the WEE1 kinase inhibitor (WEE1i), Adavosertib, can sensitize the effect of G12Ci through the MYBL2-RRM2 axis, which is associated with poor prognosis in lung cancer. Overexpressing the MYBL2-RRM2 axis or supplementing the products of the RRM2 enzyme, dNTPs/dNs, can partially reverse this synergistic inhibitory effect. We also observed marked effects of the combination therapy in tumor xenografts models. Collectively, these results uncover the WEE1 kinase inhibitors, some of which are available clinically, as effective enhancers for G12Ci therapy.

Non-small cell lung cancer (NSCLC) remains a leading cause of cancer-related mortality globally, with KRAS mutations present in approximately 20-25% of cases. The KRAS-G12C mutation, occurring in approximately 14% of lung adenocarcinomas, has emerged as a critical target for precision medicine strategies. While KRAS-G12C inhibitors, including sotorasib and adagrasib, have shown promise in clinical trials, their efficacy is limited by primary and acquired resistance mechanisms. This study explored the potential of combining anlotinib, a multi-target tyrosine kinase inhibitor, with KRAS-G12C inhibitors to overcome these resistance challenges in NSCLC treatment. Our results demonstrated that anlotinib improved the sensitivity to KRAS-G12C inhibitors in primary and acquired resistance settings, both in vitro and in vivo. Mechanistically, the combination therapy inhibited c-Myc/ORC2 signaling, leading to cell cycle arrest and apoptosis. These findings suggest that the combination of anlotinib and KRAS-G12C inhibitors represents a promising novel therapeutic approach for KRAS-G12C-mutant NSCLC.

Oncogenic KRAS mutations are frequently detected in NSCLC. It remains a major challenge to target all KRAS mutants. MEK inhibitors are considered candidates for treating KRAS-mutant NSCLC; however, their easy adaptive resistance precludes further application. Here, we found that MEK inhibitor-trametinib treatment results in the feedback activation of multiple receptor tyrosine kinases (RTKs) and that treatment with the pan-RTK inhibitor anlotinib effectively inhibits the progression of KRAS-mutant NSCLC. Furthermore, we evaluated this strategy in a clinical study (NCT04967079) involving 33 advanced non-G12C KRAS-mutant NSCLC patients. The phase Ia containing 13 patients showed that the recommended phase 2 dose (RP2D) is trametinib (2 mg) plus anlotinib (8 mg), the objective response rate (ORR) is 69.2% (95% CI: 38.6-90.9), the median progression-free survival (PFS) is 6.9 months (95% CI: 3.9 to could not be evaluated), disease control rate (DCR) is 92% (95% CI: 64.0–99.8) and the rate of adverse events (AEs) ≥grade 3 is 23%. The phase Ib containing 20 patients demonstrated the high efficacy of this combinational therapy with RP2D, with the ORR at 65% (95% CI: 40.8–84.6), the median PFS is 11.5 months (95% CI: 8.3–15.5), the median overall survival (OS) is 15.5 months (95% CI: 15.5 to could not be evaluated), the DCR at 100% (95% CI: 83.2–100.0), the median duration of overall response (DoR) is 9.3 months (95% CI: 2.5–12.1), and the rate of AEs ≥ grade 3 at 35%. Overall, this study provides a potential combinational therapeutic strategy for KRAS-mutant NSCLC through the cotargeting of MEK and RTKs.

Antimicrobial resistance in Staphylococcus aureus, especially methicillin resistant strains, contributes to severe pneumonia and septic arthritis and undermines the efficacy of standard antibiotics. We explore an antivirulence approach that targets MgrA, a global transcriptional regulator of pathogenic programs and resistance traits, and identify negletein as a small molecule that engages this target. At efficacious exposures negletein is nonbactericidal, separating virulence control from growth and with the potential to reduce selection pressure compared with bactericidal strategies. Thermal shift and intrinsic fluorescence quenching assays support direct binding to MgrA and are consistent with the involvement of residues important for the interaction. In line with target engagement, negletein reduces MgrA dependent transcription, dampens Agr quorum sensing output, and alters the surface proteome. These changes are associated with reduced adhesion to host substrates and epithelial invasion and with increased neutrophil chemotaxis. Across in vitro and in vivo models, negletein reduced cytotoxicity and intracellular bacterial burden. In murine MRSA pneumonia, treatment was associated with improved survival, lower pulmonary bacterial loads, and reduced inflammatory readouts. In experimental septic arthritis, treatment reduced joint pathology and tissue bacterial burden. Taken together, the data support MgrA as a viable antivirulence target, nominate negletein as a starting point for MRSA antivirulence development, and suggest a resistance sparing strategy that focuses on disarming pathogenicity rather than suppressing viability.

De novo purine biosynthesis (DNPS) was previously shown to be aberrantly activated in many cancers. However, the activity of DNPS pathway and its underlying regulatory mechanism in hepatoblastoma (HB) remain poorly understood. Herein, we discovered that the expression of PPAT, the rate-limiting enzyme in DNPS, was markedly upregulated in HB, leading to an augmented purine flux via DNPS, thereby promoting both HB cell proliferation and migration. Furthermore, we found that activated mutant β-catenin, a dominant driver of HB, transcriptionally activated PPAT expression, hence stimulating DNPS and constituting a druggable metabolic vulnerability in HB. Consistently, pharmacological targeting using a DNPS inhibitor lometrexol or genetic repressing the enhanced DNPS markedly blocked HB progression in vitro and in vivo. Our findings suggest that HB patients harboring activated β-catenin mutations and consequent DNPS upregulation, may be treated efficaciously with DNPS enzyme inhibitors like lometrexol. These novel findings bear major therapeutic implications for targeted precision medicine of HB.

RAS is the most frequently mutated oncoprotein for cancer driving. Understanding of RAS biology and discovery of druggable lynchpins in RAS pathway is a prerequisite for targeted therapy of RAS-mutant cancers. The recent identification of KRASG12C inhibitor breaks the “undruggable” curse on RAS and has changed the therapy paradigm of KRAS-mutant cancers. However, KRAS mutations, let alone KRASG12C mutation, account for only part of RAS-mutated cancers. Targeted therapies for cancers harboring other RAS mutations remain the urgent need. In this study we explored the pivotal regulatory molecules that allow for broad inhibition of RAS mutants. By comparing the expression levels of nucleotide pyrophosphatase (NPPS) in a panel of cell lines and the functional consequence of increased NPPS expression in RAS-mutant cells, we demonstrated that cancer cells with various kinds of RAS mutations depended on NPPS for growth and survival, and that this dependence conferred a vulnerability of RAS-mutant cancer to treatment of NPPS inhibition. RAS-mutant cells, compared with RAS-wildtype cells, bored and required an upregulation of NPPS. Transcriptomics and metabolomics analyses revealed a NPPS-dependent hyperglycolysis in RAS-mutant cells. We demonstrated that NPPS promoted glucose-derived glycolytic intermediates in RAS-mutant cells by enhancing its interaction with hexokinase 1 (HK1), the enzyme catalyzing the first committed step of glycolysis. Pharmacological inhibition of NPPS-HK1 axis using NPPS inhibitor Enpp-1-IN-1 or HK1 inhibitor 2-deoxyglucose (2-DG), or genetic interfere with NPPS suppressed RAS-mutant cancers in vitro and in vivo. In conclusion, this study reveals an unrecognized mechanism and druggable lynchpin for modulation of pan-mutant-RAS pathway, proposing a new potential therapeutic approach for treating RAS-mutant cancers.

Purine metabolism acts as the core role in human metabolic network. It offers purine metabolites as raw material for building blocks in cell survival and proliferation. Purine metabolites are the most abundant metabolic substrates in organisms. There are few reports to simultaneously quantify canonical purine metabolism in cells. A novel hydrophilic interaction liquid chromatography coupled with mass spectrometry (HILIC-MS/MS) method was developed to simultaneously determine purines profile in biological samples. Chromatographic separation was achieved using a HILIC (Waters Xbridge™ Amide) column. Different optimizing chromatographic conditions and mass spectrometric parameters were tested in order to provide the best separation and the lowest limit of quantification (LLOQ) values for targeted metabolites. The validation was evaluated according to the Food and Drug Administration guidelines. The limit of determination (LOD) and the LOQ values were in the range of 0.02-8.33 ng mL-1 and 0.1-24.5 ng mL-1, respectively. All calibration curves displayed good linear relationship of with excellent correlation coefficient (r) ranging from 0.9943 to 0.9999. Both intra-day and inter-day variability were below 15 %, respectively. Trueness, expressed as relative error, was always within ±15 %. In addition, no derivatization procedure and ion-pair reagents are in need. The innovated approach demonstrates high sensitivity, strong specificity, and good repeatability, making it suitable for absolute quantitative studies of canonical purine metabolism in cultured cells.

Opioid agonists, including morphine and its derivatives, have historically been utilized in conventional pain relief therapies. However, the morphine-like side effects associated with these compounds have constrained their broader application in clinical environments. Fortunately, novel compounds that selectively activate μ-opioid receptors (MOR) without activating the β-arrestin2 pathway, such as PZM21 and TRV130, demonstrate the potential to mitigate side effects while maintaining analgesic efficacy. In this study, we structurally modified PZM21 to get a series of compounds with a 2-cyanoguanidine scaffold, the majority of which display significant analgesic effects. Notably, Compound I-11 exhibited an analgesic effect comparable to that of morphine and selectively activates μ-opioid receptors while avoiding the activation of the β-arrestin2 pathway. Our work not only introduces a novel biased μ-opioid receptor agonist but also serves as a valuable reference for the further optimization of PZM21.

Despite significantly improved clinical outcomes in EGFR-mutant lung adenocarcinoma, all patients develop acquired resistance and malignancy on the treatment of EGFR tyrosine kinase inhibitors (EGFR-TKIs). Understanding the resistance mechanisms is crucial to uncover novel therapeutic targets to improve the efficacy of EGFR-TKI treatment. Here, integrated analysis using RNA-Seq and shRNAs metabolic screening reveals glutathione S-transferase omega 1 (GSTO1) as one of the key metabolic enzymes that is required for EGFR-TKIs resistance in lung adenocarcinoma cells. Aberrant upregulation of GSTO1 confers EGFR-TKIs resistance and tumor metastasis in vitro and in vivo dependent on its active-site cysteine 32 (C32). Pharmacological inhibition or knockdown of GSTO1 restores sensitivity to EGFR-TKIs and synergistically enhances tumoricidal effects. Importantly, nucleophosmin 1 (NPM1) cysteine 104 is deglutathionylated by GSTO1 through its active C32 site, which leads to activation of the AKT/NF-κB signaling pathway. In addition, clinical data illustrates that GSTO1 level is positively correlated with NPM1 level, NF-κB-mediated transcriptions and progression of human lung adenocarcinoma. Overall, our study highlights a novel mechanism of GSTO1 mediating EGFR-TKIs resistance and malignant progression via protein deglutathionylation, and GSTO1/NPM1/AKT/NF-κB axis as a potential therapeutic vulnerability in lung adenocarcinoma.

Targeting glucose metabolism for cancer therapy is a long-lasting pursuit but with disappointing translational success. Revelation of actionable distinctions between the malignancy traits to achieve selectivity is a prerequisite for fulfilling a therapeutic window. We discover a non-canonical glucose transporter GLUT6-facilitated, lactate-independent, glucose metabolic rewiring that selectively enables resistance to targeted therapy in lung cancer. Downstream, GLUT6 facilitated glucose influx and straying to methylglyoxal which dimerized KEAP1 and upregulated NRF2 pathway to confer resistance. Upstream, GLUT6 was transcriptionally upregulated by therapy-induced MAZ activation. Targeting GLUT6 prevented and overcame resistance to EGFR and KRAS inhibitors and the MAZ-GLUT6-NRF2 signaling correlated with clinical therapy response and relapse. Our findings uncover an unrecognized non-genetic, metabolic mechanism for drug resistance and a scenario specifically determined by a distinct glucose metabolic rewiring in cancer. The preferential dependance of the non-canonical, general-homeostasis-less-perturbing transporter GLUT6 implies a promise for resistance overcoming and for glucose metabolism-targeting strategy, two long and urgent quests. ### Competing Interest Statement The authors have declared no competing interest.

Abstract Problem-based learning (PBL) in medical education has encountered challenges affecting both teachers and students. The integration of artificial intelligence (AI) into PBL may provide potential solutions to these challenges. This paper aims to discuss the potential advantages of AI, where we found these merits of AI have the potential to improve the quality of PBL lessons. It is also important to pay attention to ethical guidelines and other limitations of AI in PBL lessons as well. Examples of interactions with AI chatbots are provided to demonstrate its application possibility. It is recommended to try using AI in PBL lessons, making it more adaptable for the PBL classroom. Future research should further explore the capabilities of AI, with the goal of developing a more personalized and adaptive learning experience within PBL.

AIMS:The antifolate methotrexate (MTX) is an anchor drug used in acute lymphoblastic leukemia (ALL) with poorly understood chemoresistance mechanisms in relapse. Herein we find decreased folate polyglutamylation network activities and inactivating FPGS mutations, both of which could induce MTX resistance and folate metabolic vulnerability in relapsed ALL. METHODS:We utilized integrated systems biology analysis of transcriptomic and genomic data from relapse ALL cohorts to infer hidden ALL relapse drivers and related genetic alternations during clonal evolution. The drug sensitivity assay was used to determine the impact of relapse-specific FPGS mutations on sensitivity to different antifolates and chemotherapeutics in ALL cells. We used liquid chromatography-mass spectrometry (LC-MS) to quantify MTX and folate polyglutamate levels in folylpoly-γ-glutamate synthetase (FPGS) mutant ALL cells. Enzymatic activity and protein degradation assays were also conducted to characterize the catalytic properties and protein stabilities of FPGS mutants. An ALL cell line-derived mouse leukemia xenograft model was used to evaluate the in vivo impact of FPGS inactivation on leukemogenesis and sensitivity to the polyglutamatable antifolate MTX as well as non-polyglutamatble lipophilic antifolate trimetrexate (TMQ). RESULTS:We found a significant decrease in folate polyglutamylation network activities during ALL relapse using RNA-seq data. Supported by functional evidence, we identified multifactorial mechanisms of FPGS inactivation in relapsed ALL, including its decreased network activity and gene expression, focal gene deletion, impaired catalytic activity, and increased protein degradation. These deleterious FPGS alterations induce MTX resistance and inevitably cause marked intracellular folate shrinkage, which could be efficiently targeted by a polyglutamylation-independent lipophilic antifolate TMQ in vitro and in vivo. CONCLUSIONS:MTX resistance in relapsed ALL relies on FPGS inactivation, which inevitably induces a folate metabolic vulnerability, allowing for an efficacious antifolate ALL treatment strategy that is based upon TMQ, thereby surmounting chemoresistance in relapsed ALL.

Colorectal cancer (CRC) is a prevalent malignant tumor often leading to liver metastasis and mortality. Despite some success with PD-1/PD-L1 immunotherapy, the response rate for colon cancer patients remains relatively low. This is closely related to the immunosuppressive tumor microenvironment mediated by tumor-associated macrophages (TAMs). Our previous work identified that a phosphoglycerate mutase 1 (PGAM1) allosteric inhibitor, HKB99, exerts a range of anti-tumor activities in lung cancer. Here, we found that upregulation of PGAM1 correlates with increased levels of M2-like tumor- associated macrophages (TAMs) in human colon cancer samples, particularly in liver metastatic tissues. HKB99 suppressed tumor growth and metastasis in cell culture and syngeneic tumor models. M2-polarization, induced by colon cancer cell co-culture, was reversed by HKB99. Conversely, the increased migration of colon cancer cells by M2-TAMs was remarkably restrained by HKB99. Notably, a decrease in TAM infiltration was required for the HKB99-mediated anti-tumor effect, along with an increase in CD8+ T cell infiltration. Moreover, HKB99 improved the efficacy of anti-PD-1 treatment in syngeneic tumors. Overall, this study highlights HKB99's inhibitory activity in TAM-mediated colon cancer progression. Targeting PGAM1 could lead to novel therapeutic strategies and enhance the effec- tiveness of existing immunotherapies for colon cancer. 2024 The Authors. Published by Elsevier B.V. on behalf of Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

The cGAS-STING pathway has long been recognized as playing a crucial role in immune surveillance and tumor suppression. Here, we show that when the pathway is activated in a cancer-cell-autonomous response manner, it confers drug resistance. Targeted or conventional chemotherapy drugs promoted cytosolic DNA accumulation in cancer cells, activating the cGAS-STING pathway and downstream TBK1-IRF3/NF-κB signaling. This cancer cell-intrinsic response enabled the cells to counteract drug stress, allowing treatment resistance to be acquired and maintained. Blockade of stimulator of interferon genes (STING) signaling delayed and overcame resistance in models in vitro and in vivo. This finding uncovers an alternative face of cGAS-STING signaling other than the well-reported modulation of microenvironmental immune cells. It also implies a caution for the combination of STING agonist with targeted or conventional chemotherapy drug treatment, a strategy prevailing in current clinical trials.