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Sphingosine-1-phosphate (S1P) is a critical bioactive lipid mediator that regulates essential cellular processes-including proliferation, survival, migration, and inflammation-through binding to its cognate receptors (S1PRs) on the cell membrane or via direct intracellular actions. Sphingosine Kinase 2 (SphK2) has thus emerged as a promising therapeutic target. In this study, we designed and synthesized a novel series of SphK2 inhibitors (Q-series) based on the lead compound K145. Among these, compounds Q20 (IC50 = 2.6 ± 0.46 μM), Q24 (IC50 = 4.27 ± 1.51 μM), and Q25 (IC50 = 6.25 ± 0.62 μM) displayed potent and selective inhibition of SphK2, while showing negligible activity against SphK1 (IC50 > 50 μM). Notably, Q25 exhibited significant anti-proliferative effects against multiple colorectal cancer cell lines (LOVO, SW480, SW620, HT-29), with IC50 values of 8.09 ± 4.36, 7.77 ± 2.48, 7.38 ± 3.41, and 6.41 ± 2.46 μM, respectively. Mechanistically, Q25 induced S-phase cell cycle arrest and apoptosis. The Q-series compounds (Q20, Q24, Q25) also demonstrated favorable metabolic stability in human liver microsomes, characterized by prolonged half-lives (T1/2 > 90 min), low intrinsic clearance (CLint(mic) < 15 μL/min/mg), and high parent compound recovery (∼50% remaining after incubation). In vivo pharmacokinetic studies in mice indicated that Q25 is rapidly metabolized, classified as a high-clearance compound, and undergoes extrahepatic elimination. In a SW480 xenograft mouse model, Q25 effectively inhibited tumor growth without observable toxicity. Western blot analysis suggested that its anti-tumor effect is associated with reduced S1P production and subsequent suppression of the NF-κB pathway. In summary, these findings identify Q25 as a promising, selective SphK2 inhibitor worthy of further development as an anticancer agent.

Point-of-care testing (POCT) platforms frequently suffer from a fundamental bottleneck: while advances in molecular amplification improve signal intensity, the reliability of signal readout in complex clinical matrices remains poorly controlled. Here, we present an integrated biosensing framework that treats readout reliability as an explicit engineering objective rather than a post hoc correction problem. The platform integrates three complementary components: (i) a heptameric nanobody probe employed as a multivalent recognition element for target capture, (ii) a DNA-assisted clustering interface that spatially organizes gold nanoparticle reporters for robust signal amplification, and (iii) a few-shot learning module based on Prototypical Networks that enables robust classification with minimal training data while providing interpretable decision-making through metric-based reasoning. Alpha-fetoprotein was selected as the model analyte because it remains a clinically important biomarker for hepatocellular carcinoma screening and follow-up, while also representing a realistic POCT challenge in which clinically meaningful detection must be achieved with low instrumentation burden and reliable readout under matrix variability. In this setting, the system achieves a visual limit of detection of 2 ng/mL and demonstrates quantitative consistency across representative clinical serum samples. Importantly, the AI module functions as an integral system component, identifying diagnostically relevant regions and mitigating readout uncertainty arising from matrix effects and imaging variability. By jointly engineering the sensing interface and the interpretive layer, this work establishes a generalizable strategy for constructing trustworthy POCT systems in which chemical signal generation and digital interpretation are co-designed.

Epidermal growth factor receptor (EGFR) serves as a key therapeutic target for solid tumors such as non-small cell lung cancer (NSCLC), where its mutations and overexpression often lead to sustained activation of oncogenic signaling pathways. This study represents a comparative analysis of multiple targeted chimeric degradation technologies targeting EGFR allosteric sites, aiming to provide clearer guidance for the future development of allosteric EGFR degraders. Results demonstrate that the VHL-based PROTAC compound III-4 exhibits optimal degradation activity against EGFRWT and EGFRDel19, degrading approximately 76% and 72% at 0.1 μM, respectively, with degradation partially dependent on the ubiquitin-proteasome pathway. For degrading the acquired resistance mutant EGFRL858R/T790M, CRBN-based PROTAC compounds II-3 and II-5 demonstrated significant efficacy (approximately 60% degradation at 0.1 μM) and effectively inhibited H1975 cell proliferation (IC50 values of 23.32 μM and 14.31 μM, respectively). In contrast, AUTAC and HyT-type compounds exhibited overall weaker degradation activity, relying on the autophagy-lysosomal pathway and proteasome pathway, respectively. Physicochemical analysis indicated that PROTAC compounds exhibited cLogP and polar surface area (PSA) values closer to the ideal range, potentially contributing to their cellular permeability and degradation activity. In summary, this study represents a deepened and extended investigation built directly on previous seminal work, aiming to provide clearer guidance for the future development of allosteric EGFR degraders.

A novel series of heterocyclic compounds was developed, synthesized, and assessed for their in vitro anticancer efficacy and EGFR inhibitory activities. The cytotoxicity of the synthesized compounds was evaluated against A-549 and NCI-H460 lung cancer cell lines, as well as normal HEK-293 cells, using erlotinib and doxorubicin as reference standards. Multiple compounds had considerable anticancer efficacy, with 8f and 8g identified as the most effective possibilities, with IC₅₀ values ranging from 2.53 to 6.51 μM, surpassing erlotinib. These compounds exhibited significant EGFR inhibition, with 8f (IC₅₀ = 0.26 μM) and 8g (IC₅₀ = 0.36 μM) surpassing the standard drug. Molecular docking analyses of the EGFR kinase domain demonstrated advantageous binding affinities and significant interactions with the hinge region residue MET769, corroborated by many hydrogen bonds and substantial π-interactions. A strong association between docking scores and biological activity was noted, validating EGFR as a potential molecular target. The findings designate 8f and 8g as prospective lead compounds for further development as EGFR-targeted anticancer therapies.

Several studies have shown that fibroblast activation protein (FAP)-targeted radioligands with an α-ketoamide as the warhead can lead to high affinity for FAP and prolonged tumor retention. However, the preparation of reported FAP-targeted ligands requires multiple solution-phase synthesis and purification steps. Herein, we report a simple solid-phase approach for synthesizing DOTA-conjugated α-ketoamide-based FAP-targeted ligands. The new ligand, FAPI-CRC, was constructed on Rink Amide MBHA resin by sequentially coupling Fmoc-protected amino acids and DOTA-tris(tert-butyl ester), oxidation of α-hydroxyamide to α-ketoamide by 2-iodoxybenzoic acid in dimethyl sulfoxide, and final cleavage/deprotection with trifluoroacetic acid, followed by HPLC purification. FAPI-CRC was labeled with natGa/68Ga to investigate its ability to target FAP in vitro and in vivo, respectively. natGa-FAPI-CRC was obtained in 50% yield and [68Ga]Ga-FAPI-CRC was obtained in 27% decay-corrected radiochemical yield with >99% radiochemical purity and a molar activity of 30.8 GBq/μmol. FAPI-CRC and natGa-FAPI-CRC exhibited high affinity for FAP with IC50 values of 0.33 ± 0.09 and 0.42 ± 0.27 nM, respectively. Positron emission tomography (PET) imaging and ex vivo biodistribution studies in mice showed that [68Ga]Ga-FAPI-CRC was specifically taken up by HEK293T:hFAP tumor xenografts with good tumor-to-background contrast at 1 h post-injection. Therefore, our simple solid-phase approach is promising for the synthesis of potent α-ketoamide-based FAP-targeted ligands and can be used to greatly facilitate the development of radiopharmaceuticals for the management of FAP-expressing cancer.

The immune checkpoint programmed ligand 1 (PD-L1) is expressed in various solid tumors and is associated with immunotherapy prognosis. Dynamic assessment of PDL1 expression levels helps identify patients who may benefit from immunotherapy. Atezolizumab is a monoclonal antibody that targets PD-L1 and is used in the treatment of various hematologic malignancies and solid tumors. However, research on colon cancer is lacking. Approximately 85% of colorectal cancer (CRC) patients have the MSS/pMMR (Microsatellite Stable/proficient Mismatch Repair) subtype, which lacks ideal biomarkers for precise and dynamic screening of potential immune-responsive subpopulations and for predicting combination therapy strategies. Currently, the assessment of PD-L1 is limited to biopsy samples. Molecular immuno-PET imaging can provide an effective solution for guiding clinical immunotherapy selection. This study describes the development of 89Zr-DFO-atezolizumab, a PD-L1-targeted immuno-imaging agent, and its evaluation in terms of in vitro and in vivo specificity as well as pharmacokinetics. Tumor uptake and heterogeneity were quantified in mouse models via immuno-PET imaging. PET/CT scans using 89Zr-DFO-atezolizumab revealed a significant difference in tumor uptake between the MC38hPD-L1 model and the MC38 model, and cold anti-atezolizumab effectively blocked this uptake. The preliminary dosimetry study indicated that the organs receiving higher doses are the spleen and the liver. Preclinical PET/CT imaging with 89Zr-DFO-atezolizumab reveals its potential for the non-invasive detection of PD-L1-positive CRC tumors, which holds potential significance for understanding tumor heterogeneity and monitoring early PD-L1 expression changes induced by therapy.

Skin pigmentation disorders present a significant therapeutic challenge, often arising from disturbances in melanin metabolism that lead to uneven pigmentation and skin damage. Tyrosinase (TYR), the key enzyme in melanin biosynthesis, serves as a crucial therapeutic target for managing hyperpigmentation and pigmentary skin diseases. In this study, we performed structure-based virtual screening of a comprehensive library of FDA-approved drugs and chemical active agents against tyrosinase and selected top-ranked compounds based on predicted binding affinities and favorable binding poses for experimental validation. In vitro assays confirmed that nine compounds inhibited mushroom tyrosinase (mTYR) with IC50 values of 6.3-23.4 μM. Among them, rosmarinic acid (compound 1) and ferulic acid (compound 3) also inhibited human tyrosinase (hTYR) with IC50 values of 7.8 ± 0.4 and 9.3 ± 0.5 μM, respectively. Enzyme kinetic analysis indicated a competitive inhibition mechanism against mTYR for the most active compounds. In α-melanocyte stimulating hormone (MSH)-stimulated B16F10 cells, the selected hits produced measurable anti-melanogenic effects within the tested concentration range, with cellular IC50 = 37.8-108.1 μM. Additionally, molecular dynamics simulations of rosmarinic acid in complex with hTYR confirmed a stable binding mode characterized by persistent coordination within the dicopper active site. These findings identify repurposable small-molecule scaffolds with tyrosinase-inhibitory activity and highlight rosmarinic acid as a promising lead for further development. Although the present study is limited to in vitro enzymatic and cellular evaluation, it provides a useful foundation for future validation in human skin-derived systems and in vivo models.

Cancer remains the second leading cause of death globally, primarily because of the shortcomings of existing treatments, which include early drug resistance, metastasis, inadequate pharmacokinetics, and systemic toxicity. Small-molecule inhibitors that target the interaction of MDM2 and p53 show promise for reactivating p53 function and suppressing tumor growth. In this study, we designed, produced, and evaluated a number of 2-(4-((2,4-difluorobenzylidene)amino)-5-mercapto-4H-1,2,4-triazol-3-yl)phenol derivatives as possible anticancer agents utilizing both in silico and in vitro approaches. All obtained compounds showed effective binding interactions, as evidenced by their high docking scores. Molecular dynamics (MD) simulations validated the structural stability, compactness, and rigidity of the most active molecule during a 100 ns time period. ADMET predictions indicated good pharmacokinetic parameters and low toxicity profiles, whereas DFT investigates validated the compounds' reactive features and electronic compatibility for biological activity. The structures of the synthesized compounds were confirmed through 1H NMR, 13C NMR, IR, and ESI-MS analyses. The anticancer activity in vitro was assessed using the MTT assay on MCF-7 and A549 cell lines. Of all the compounds tested, compound 8D, N-(benzo[d]thiazol-2-yl)-2-((4-((2,4-difluorobenzylidene)amino)-5-(2-hydroxyphenyl)-4H-1,2,4-triazol-3-yl)thio)acetamide, exhibited the strongest activity against MCF7 & A549 cells, with an IC₅₀ value of 7.56 & 7.22 μM respectively. This study identifies a new class of small-molecule inhibitors that interact with p53 and MDM2, characterized by low toxicity and high efficacy, which could be turned into anticancer drugs. These findings are essential for medicinal chemists and researchers working on the discovery of anticancer medicines.

Breast cancer remains one of the leading causes of cancer-related mortality among women worldwide, highlighting the urgent need for novel therapeutic agents. In this study, a series of pyrimidine-based derivatives were designed and synthesized to evaluate their potential as anti-breast cancer agents. The compounds were screened for anti-proliferative activity against MDA-MB-231 breast cancer cells, and selected candidates were further assessed for CDK2 inhibitory potential. Among the synthesized compounds, 7b (IC₅₀ = 4.21 ± 0.62 μM) and 7d (IC₅₀ = 5.16 ± 0.71 μM) exhibited potent cytotoxicity and induced apoptosis, with 7d also demonstrating significant CDK2 inhibition. Computational studies, including molecular docking, molecular dynamics simulations, and binding energy analyses, revealed stable interactions within the CDK2 active site. Additionally, ADMET predictions indicated favorable pharmacokinetic and drug-like properties. Overall, these findings suggest that pyrimidine-based compounds, particularly 7b and 7d, possess promising anti-proliferative properties, with CDK2 inhibition contributing to their mechanism of action and supporting their potential as lead candidates for breast cancer therapy.

KRAS-mutant tumors remain a major challenge in cancer therapy. Although current targeted drugs show initial promise, their efficacy is often limited by the development of resistance. Therefore, identifying effective drug combinations to target KRAS-mutant tumors is of great significance. This study investigates the synergistic potential of romidepsin (RO), a class I HDAC inhibitor, in combination with adagrasib (ADA). In vitro experiments demonstrated that RO exhibits potent antitumor activity, with significant efficacy against KRAS-mutant cells. Mechanistic studies revealed that RO exerts its effect by suppressing NRF2. More importantly, its combination with ADA enhanced cytotoxicity and further suppressed NRF2 expression, resulting in increased ROS levels, induction of cytotoxic autophagy, and inhibition of the downstream AKT pathway. In vivo xenograft models confirmed that the combination of RO and ADA significantly reduced tumor growth. These findings suggest that RO and ADA act synergistically against KRAS-mutant tumors by suppressing NRF2, supporting their potential as a targeted combination strategy for KRAS-driven cancers.