Search Results (288)

Chagas disease, caused by Trypanosoma cruzi, affects a significant proportion of patients who develop digestive and cardiac complications, including megaviscera. This pathogenesis has been associated with autoimmune mechanisms mediated by molecular mimicry. In this study, an in silico evaluation of the potential structural basis of cross-reactivity of β-tubulin 1.9 of T. cruzi and the human β-4A tubulin isoform 3 was conducted. Using bioinformatics tools, homologous regions were identified and potentially immunogenic epitopes were predicted, considering their structural modeling and molecular docking. The proteins shared 87% sequence identity and 95% similarity, with an almost identical structural overlap, RMSD 0.291 Å. Three epitopes, VPFPRLHFF, NDLVSEYQQYQDATI, and GQSGAGNNWAKGHYTEGAELIDS, exhibited high predicted antigenicity, with the 9-mer and 16-mer peptides displaying structurally compatible docking poses within the binding grooves of MHC class I and class II molecules, respectively, while B-cell epitope potential was inferred from sequence-based property predictions. Normal mode analysis, used as an exploratory approach, suggested comparable flexibility profiles for the parasitic- and human-derived peptide–MHC complexes. These findings provide an exploratory structural framework supporting a potential role of β-tubulin epitopes in molecular mimicry processes implicated in the development of chagasic megaviscera. Full article

Fruit sclerotiniosis (FS) is becoming the most important disease in recently transformed mulberry fruit gardens (TFMGs), where traditional production of mulberry leaves for sericulture takes place; FS has a long history as a secondary disease in Zhejiang province, China. Thiophanate-methyl and boscalid are the two main fungicides adopted for the management of FS in these gardens. A decrease in efficacy has been observed by growers and local technicians. For this new situation regarding TFMGs, however, the resistance status of them has not yet been investigated and reported. In the present study, pathogens were isolated from diseased fruits and identified through a combination of morphological characteristics with ITS sequence analysis. Results showed that the pathogens included Scleromitrula shiraiana and Sclerotinia sclerotiorum. All isolates of S. shiraiana (n = 12) and S. sclerotiorum (n = 12) were sensitive to boscalid, and no resistance was detected. The S. shiraiana sub-population was sensitive to thiophanate-methyl, whereas the S. sclerotiorum sub-population developed resistance with a frequency of 33.3%. Thiophanate-methyl-resistant (Th^R) S. sclerotiorum grew faster at a low temperature (15 °C) than sensitive ones. These Th^R exhibited negative cross-resistance to diethofencarb, as previously observed in Botrytis cinerea, and showed no cross-resistance to procymidone or boscalid. Further studies indicated that resistance to thiophanate-methyl is caused by a novel double mutation (E198V+V349I) in the β-tubulin of S. sclerotiorum. This E198V+V349I mutation produced structural alterations in the β-tubulin protein, the action target of thiophanate-methyl, leading to reorientation of the substrate binding site and conformational change in the active pocket. In conclusion, avoiding the sole use of thiophanate-methyl on TFMGs is necessary. Application of boscalid in combination or rotation with other fungicides without cross-resistance is recommended for the management of FS in TFMG practices. Full article

Background/Objectives: Microtubule-targeting agents remain foundational components of anticancer chemotherapy, yet their clinical utility is constrained by resistance and toxicity. Methods: Here, we present a theoretical exploration of a plausible “dual” binding pocket that spans the α-tubulin pironetin site and the inter-subunit todalam site. Eight virtual chimeric ligands, each merging key pharmacophoric elements of pironetin and todalam, were constructed and covalently docked to Cys316 of α-tubulin. Results: Covalent docking followed by 200 ns all-atom molecular dynamics simulations revealed that two derivatives (compounds 4 and 8) stably occupy the merged cavity, simultaneously anchoring in the pironetin region via Michael addition and in the todalam region via π-stacking and hydrogen bonding. These hybrids preserved the critical hydrogen-bonding networks of both parent ligands and exhibited low ligand RMSD values (~1.5 Å) and compact radii of gyration throughout the simulations, indicating a tight, persistent binding. Estimated HYDE affinities of 1.5 µM for compound 4 and 17.6 µM for compound 8, calculated with SeeSAR, suggest that covalent engagement can compensate for moderate non-covalent binding scores. Conclusions: In summary, our results provide compelling grounds for developing a new class of α-tubulin inhibitors that engage the hybrid pocket, laying a foundation for the structure-guided synthesis of first-in-class dual-site compounds capable of overcoming resistance to conventional microtubule-targeting drugs. Full article

Benign prostatic hyperplasia (BPH) is a common disease in elderly men; its occurrence is closely related to the interaction between stromal cells and epithelial cells in the prostate. This article aims to explore the potential therapeutic effect and mechanism of a new trifluoromethyl quazoline compound (kzl054) on BPH. The results showed that kzl054 had inhibitory activity that limited the growth of prostate hyperplasia cells, BPH-1, and stromal cells, WPMY-1. It could also induce apoptosis of BPH-1 cells and arrest their cell cycle. animal experiment results showed that kzl054 could effectively reduce the volume and prostate index of mouse prostate hyperplasia tissues. Through the establishment of a co-culture system of BPH-1 and WPMY-1 cells, it was found that co-culture could induce EMT in BPH-1 cells. While kzl054 could affect the secretion of TGF-β1 by competitively binding to the colchicine binding site on β-tubulin and inhibiting the expression of β-tubulin, through inhibiting the secretion of TGF-β1 by stromal cells. This study has revealed that compound kzl054 inhibits the secretion of TGF-β1 by targeting the inhibition of microtubule polymerization and regulating the epithelial cell EMT, providing potential candidate molecules and mechanisms for the development of new drugs for the treatment of BPH. Full article

Histone deacetylases (HDACs) are pivotal epigenetic regulators that control gene expression, cell proliferation, and differentiation, and their dysregulation is closely associated with the onset and progression of multiple cancers. The therapeutic importance of these enzymes is reflected by FDA approval of HDAC inhibitors for oncology indications. Despite this clinical success, most FDA-approved agents employ conventional zinc-binding groups (ZBGs) such as hydroxamic acid and 2-aminoanilide, which are frequently linked to metabolic instability, genotoxicity, and poor pharmacokinetic behavior. These limitations have spurred the development of structurally diverse and safer HDAC inhibitors incorporating alternative ZBGs. This review provides a comprehensive analysis of recently developed HDAC inhibitors reported in the last few years, emphasizing their structure–activity relationships (SARs), chemical scaffolds, and binding features—including cap, linker, and ZBG motifs. Both hydroxamate-based and non-hydroxamate inhibitors, such as benzamides, hydrazides, and thiol-containing analogs, are critically evaluated. Moreover, the potency and selectivity profiles of these inhibitors are summarized across different cancer and normal cell lines, as well as specific HDAC isoforms, providing a clearer understanding of their therapeutic potential. Emerging dual-target HDAC inhibitors, such as HDAC–tubulin, HDAC–PI3K and HDAC–CDK hybrids, are also discussed for their synergistic anticancer effects. Full article

Microtubule minus-end binding proteins (−TIPs) are critical regulators of microtubule dynamics and stability, whose dysfunctions are increasingly associated with tumorigenesis and cancer progression. This review systematically consolidates current research advances on the molecular characteristics, oncogenic mechanisms, and therapeutic potential of −TIPs in cancer. By integrating preclinical studies, multi-omics data, and clinical evidence, it was found that calmodulin-regulated spectrin-associated proteins (CAMSAPs) and abnormal spindle microtubule assembly (ASPM) primarily exhibit oncogenic properties, whereas CAMSAP3 acts as a tumor suppressor by negatively regulating tumor cell migration. Studies also demonstrate that pharmacological inhibition of the γ-tubulin ring complex (γ-TuRC) effectively attenuates the centrosomal hyper-clustering capacity of malignant cells, thereby suppressing invasive phenotypes. This result underscores the therapeutic value of targeting −TIPs. In summary, −TIPs play critical and complex roles in cancer progression and hold significant potential as prognostic biomarkers and therapeutic targets. Intervention strategies focusing on specific −TIPs, such as γ-TuRC, offer promising strategies for precision cancer therapy; however, the context-dependent functions of these proteins require further investigation to facilitate clinical translation. Full article

Sesquiterpene lactones (SLs) are plant-derived metabolites with recognized pharmacological properties. Dysfunction of the primary cilium (PC), a solitary sensory organelle essential for development, is associated with disorders such as ciliopathies and tumors. While previous studies have shown that certain SLs can alter PC structure in human retinal cells, their influence on ciliary signaling pathways remains unclear. In this study, we examined the effect of four SLs—grosheimin, costunolide, α-cyclocostunolide (α-C), and β-cyclocostunolide (β-C)—on ciliary function in human primary fibroblasts. Using immunofluorescence and qPCR to assess cilia structure and Hedgehog (Hh) pathway activation, we found that grosheimin enhanced ciliogenesis without affecting Hh signaling. In contrast, costunolide, α-C, and β-C disrupted ciliary structure and suppressed the Hh pathway transcripts Gli1 and Ptch1. RNA sequencing revealed that grosheimin upregulated genes related to microtubule binding and ciliogenesis, whereas α-C downregulated tubulin subunit transcripts. These findings suggest distinct molecular mechanisms through which SLs affect ciliary structure and function. Collectively, this study highlights the potential of specific SLs as modulators of ciliary signaling, offering promising leads for therapeutic strategies targeting ciliopathies and tumors. Full article

Dynein is a minus-end-directed microtubule motor that transports a variety of cargoes. Cargo specificity is mediated by a class of adaptor proteins that bind to the interface between dynein and dynactin, along the length of the Arp1 filament of dynactin, and that co-activate the motor. NuMA, ninein, and ninein-like protein (Nlp) are cargo-adaptors that are involved in microtubule organization, rather than carrying portable cargoes. At the same time, ninein and Nlp are believed to be anchorage factors for gamma-tubulin ring complexes to the centrosome. Here, we discuss recent findings on the interaction of NuMA and ninein with the dynein/dynactin complex, and how these findings challenge earlier concepts on ninein-dependent microtubule organization via gamma-tubulin complexes. We do not intend to provide an encyclopedic review on NuMA and ninein, but rather develop a hypothesis about how conformational changes may regulate the activities and binding specificities of these two proteins. Full article

The tubulin polymerization promoting proteins (TPPPs) are a small family of conserved proteins originally characterized as microtubule binding proteins. TPPP1, the first identified member, both binds to and bundles microtubules. Its homologs, TPPP2 and TPPP3, are encoded by separate genes on distinct chromosomes but both lack the N-terminal tail present in TPPP1. Functional studies revealed that TPPP3 retains comparable microtubule binding and bundling capacity to TPPP1, whereas TPPP2 displays markedly reduced binding and no bundling activity. Intriguingly, TPPP3 has been implicated in many different diseases. In this review, we summarize the current findings on TPPP3 and its dysregulation in various diseases including cancer, reproductive dysfunction, musculoskeletal conditions, endothelial dysfunction, and neurodegenerative diseases. Full article

Background/Objectives: A series of 1-(3,5-dimethoxyphenyl)azetidine-2-ones were synthesised to evaluate their antiproliferative activity in MCF-7 breast cancer cells and HT-29 chemoresistant colon cancer cells. The 1,4-diarylazetidin-2-ones were designed by replacing the characteristic 3,4,5-trimethoxyphenyl Ring A of the antimitotic stilbene combretastatin CA-4 with a 3,5-dimethoxyphenyl substituent at N-1, together with phenyl, hydroxyl, and phenoxy substituents at C-3 of the four-membered ring. Methods: A panel of 12 novel compounds was synthesized and evaluated in estrogen receptor (ER)- and progesterone receptor (PR)-positive MCF-7 breast cancer cells followed with the more potent compounds further evaluated in HT-29 chemoresistant colon cancer cells. Cytotoxicity was determined by LDH assay. The structures of the 1-(3,5-dimethoxyphenyl)azetidine-2-ones 12i, 12k, 12o, 12p together with the 1-(3,5-dimethoxyphenyl)azetidine-2-one 12s were determined by X-ray crystallography. The trans configuration of the C-3 and C-4 substituents of the β-lactam ring was confirmed for compounds 12k and 12u. Molecular modelling and molecular dynamics studies examined the molecular interactions of the compounds with the colchicine binding site of tubulin. Results: The 1-(3,5-Dimethoxyphenyl)-4-(4-ethoxyphenyl)-3-hydroxyazetidin-2-one 12l was identified as the most potent antiproliferative compound in the series (with an IC₅₀ value of 10 nM in MCF-7 breast cancer cells and 3 nM in HT-29 colon cancer cells) and with greater potency than CA-4 in the chemoresistant HT-29 cells. Computational docking studies predicted binding conformations for 12l and the related series of compounds in the colchicine binding site of tubulin and rationalised the impact of the 3,5-dimethoxyphenyl substituent at N-1 of the azetidine-2-one on activity. Conclusions: These findings indicate that the novel 1-(3,5-dimethoxyphenyl)-2-azetidinone 12l is a suitable candidate for further investigation as a potential antiproliferative microtubule-targeting agent for breast and chemoresistant colon cancers. Full article

Background: Histone deacetylase 6 (HDAC6) is a unique class IIb HDAC isozyme characterized by two catalytic domains and a zinc finger ubiquitin-binding domain. It plays critical roles in various cellular processes, including protein degradation, autophagy, immune regulation, and cytoskeletal dynamics. Due to its multifunctional nature and overexpression in several cancer types, HDAC6 has emerged as a promising therapeutic target. Methods: In this study, we employed a ligand-based pharmacophore modeling approach using a structurally diverse set of known HDAC6 inhibitors. This was followed by the virtual screening of over 140,000 commercially available compounds from both the MolPort and Asinex databases. The screening workflow incorporated pharmacophore filtering, molecular docking, and molecular dynamic (MD) simulations. Binding free energies were estimated using Molecular Mechanics Generalized Born Surface Area (MM-GBSA) analysis to prioritize top candidates. A fluorometric enzymatic assay was used to measure HDAC6 activity, while cell viability assay by Cell Titer Glo was used to assess the anti-tumor activity against drug-sensitive and -resistant multiple myeloma (MM) cells. Western blotting was used to evaluate the acetylation of tubulin or histone H4 after treatment with selected compounds. Results: Three promising compounds were identified based on stable binding conformations and favorable interactions within the HDAC6 catalytic pocket. Among them, Molecular Mechanics Generalized Born Surface Area (MM-GBSA) analysis identified Compound 10 (AKOS030273637) as the top theoretical binder, with a ΔG_bind value of −45.41 kcal/mol. In vitro enzymatic assays confirmed its binding to the HDAC6 catalytic domain and inhibitory activity. Functional studies on MM cell lines, including drug-resistant variants, showed that Compound 10 reduced cell viability. Increased acetylation of α-tubulin, a substrate of HDAC6, likely suggested on-target mechanism of action. Conclusions: Compound 10, featuring a benzyl 4-[4-(hydroxyamino)-4-oxobutylidene] piperidine-1-carboxylate scaffold, demonstrates potential drug-like properties and a predicted bidentate zinc ion coordination, supporting its potential as an HDAC6 inhibitor for further development in hematologic malignancies. Full article

Three new series of indolizines (5a–f, 6a–f and 7a–g), functionalized with bromine or ethyl ester substituents on the pyridine ring, were designed and synthesized as promising anticancer agents. The synthesis of indolizine derivatives was carried out using the 1,3-dipolar cycloaddition of pyridinium N-ylides to ethyl propiolate as a key step. Spectral characterization (using NMR, FT-IR, HRMS and X-ray diffraction) showed that two types of cycloadducts 5a–f and 6a–f were obtained when the ylides generated by the 3-bromopyridinium salts were used as 1,3-dipoles in Huisgen cycloaddition reactions to ethyl propiolate. The anticancer effect of selected compounds was in vitro assessed against the National Cancer Institute (NCI) panel of 60 human tumor cells, at 10 μM concentration, with three compounds (5c, 6c and 7g) showing promising inhibitory activity on the growth of several cell lines including lung, brain, renal cancer and melanoma, as well as a cytotoxic effect against HOP-62 non-small cell lung cells (34% for compound 5c and 15% for compound 7g) and SNB-75 glioblastoma cells (15% for compound 5c and 14% for derivative 7c). Molecular docking revealed favorable binding affinities for 5c, 6c and 7g (–9.22 to –9.88 kcal/mol) at the colchicine-binding site of tubulin with key interactions involving βASN-258, βALA-317, and βLYS-352 residues for 5c, βASN-258 in case of 6c, and αVAL-181 and βLYS-254 for derivative 7g. According to the in silico ADMET analysis, the active compounds are predicted to exhibit good oral bioavailability, promising drug-like qualities and low toxicity risks. Full article

Microtubules play a key role in cell division and cell migration. Thus, microtubule-targeting agents (MTAs) are pivotal in cancer therapy due to their ability to disrupt cell division microtubule dynamics. Traditionally divided into stabilizers and destabilizers, MTAs are increasingly being repurposed for central nervous system (CNS) applications, including brain malignancies such as gliomas and neurodegenerative diseases like Alzheimer’s and Parkinson’s. Microtubule-stabilizing agents, such as taxanes and epothilones, promote microtubule assembly and have shown efficacy in both tumour suppression and neuronal repair, though their CNS use is hindered by blood–brain barrier (BBB) permeability and neurotoxicity. Destabilizing agents, including colchicine-site and vinca domain binders, offer potent anticancer effects but pose greater risks for neuronal toxicity. This review highlights the mapping of nine distinct tubulin binding pockets—including classical (taxane, vinca, colchicine) and emerging (tumabulin, pironetin) sites—that offer new pharmacological entry points. We summarize the recent advances in structural biology and drug design, enabling MTAs to move beyond anti-mitotic roles, unlocking applications in both cancer and neurodegeneration for next-generation MTAs with enhanced specificity and BBB penetration. We further discuss the therapeutic potential of combination strategies, including MTAs with radiation, histone deacetylase (HDAC) inhibitors, or antibody–drug conjugates, that show synergistic effects in glioblastoma models. Furthermore, innovative delivery systems like nanoparticles and liposomes are enhancing CNS drug delivery. Overall, MTAs continue to evolve as multifunctional tools with expanding applications across oncology and neurology, with future therapies focusing on optimizing efficacy, reducing toxicity, and overcoming therapeutic resistance in brain-related diseases. Full article

Background: Parasitic worm infections remain among the most prevalent and neglected health issues worldwide, affecting both humans and animals. Toxocariasis, caused by Toxocara spp., is a widespread zoonosis with significant public health and economic implications. Current anthelmintic treatments show limited efficacy, particularly against tissue-migrating larvae, underscoring the urgent need for new therapeutic options. This study aimed to evaluate the anthelmintic potential of H₁ antihistamines as repurposed drug candidates against Toxocara canis. Methods: Twenty-two H₁ antihistamines were screened for larvicidal activity against infective third-stage (L3) larvae of T. canis. Larval motility and morphology were assessed, and compounds with the highest efficacy were further investigated using density functional theory (DFT) to explore their electronic properties. Molecular docking simulations were also performed to predict interactions with T. canis β-tubulin. Results: Promethazine and rupatadine exhibited significant larvicidal effects, surpassing albendazole in reducing larval motility and inducing a distinct contorted morphology not observed in control or albendazole-treated larvae. DFT analyses suggested a strong electron-acceptor capacity, indicating a potential redox-based mechanism of action. Docking studies revealed favorable binding to the colchicine site of T. canis β-tubulin. Conclusions: This is the first report of larvicidal activity of antihistamines against T. canis, supporting their potential as repurposed therapeutic agents for the treatment of zoonotic helminthiases, particularly those caused by tissue-migrating nematodes. Full article

A series of novel podophyllotoxin derivatives containing benzothiazole scaffolds were synthesized and evaluated for their in vitro cytotoxic activity against five cancer cell lines (MCF-7, SKOV-3, B16F10, LOVO, and HeLa). Two compounds, 7 and 11, which are different only by the absence or presence of the ester group, showed the strongest cytotoxic effect towards all tested cancer cell lines with the IC₅₀ 0.68–2.88 µM. In addition, it was demonstrated that these compounds inhibit cancer cell proliferation by inducing G2/M phase arrest in HeLa cells. The structure–activity relationship was analyzed and it confirmed the importance of the core structural features like a dioxolane ring and free-rotating trimethoxyphenyl group for cytotoxicity. Moreover, the R configuration of the ester group at the C-8′ position proved to be substantial since its epimer was inactive. The molecular docking studies revealed that the most potent compounds have a different binding mode to β-tubulin than podophyllotoxin; however, the benzothiazole fragment docked in a similar location as the trimethoxyphenyl group of podophyllotoxin, exhibiting similar hydrophobic interactions. These findings clearly indicate that podophyllotoxin–benzothiazole derivatives could be addressed for further pharmacological studies in anticancer research. Full article