Search Results (57)

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

Ovarian cancer cells overexpress HDAC6, and selective HDAC6 inhibitors have been considered potential new drugs for ovarian cancer either alone or in combination with other anticancer agents. We screened 46 potential novel HDAC6 inhibitors in ES-2 ovarian cancer cells and showed that compound 25253 demonstrated the most potent anti-proliferative activity and effective synergy with paclitaxel, which was also validated in TOV21G ovarian cancer cells. The combination of 25253 and paclitaxel significantly induced subG1 and apoptotic cells, revealed by PI staining assay and Annexin V-FITC/PI double staining assay, respectively. Western blot analysis showed downregulation of Bcl-2 and Bcl-XL, and upregulation of Bax and Bak, indicating that apoptosis was mediated through the intrinsic pathway. The combination increased γ-H2AX and p-p53 protein levels, suggesting the induction of DNA damage. Furthermore, HDAC6 was downregulated and acetylated α-tubulin was profoundly increased. Compound 25253 enhanced the inhibitory effect of paclitaxel on cell migration and invasion, possibly due to the extensive accumulation of acetylated α-tubulin, which affected microtubule dynamics. Taken together, the combination of 25253 and paclitaxel synergistically inhibited the growth, migration, and invasion of ovarian cancer cells and induced apoptosis, providing supporting evidence that the combination of HDAC6 inhibitors and paclitaxel may be a promising treatment strategy for ovarian cancer. Full article

In this study, we assessed the ability of 2-Cl-MGV-1 (2-chlorophenyl quinazolin-4-yl, dimethyl carbamate), a ligand of the 18 kDa mitochondrial translocator protein (TSPO), to mitigate brain damage in a mouse model of traumatic brain injury (TBI). TSPO is important for arresting the death of neurons and glia and counteracting microglial activation, and it provides anti-inflammatory activity, promotes regeneration (including neurons), and contributes to angiogenesis. We assessed the minimal dose of the TSPO ligand 2-Cl-MGV-1 that attenuates the magnitude of brain damage as well as the time window following TBI in which the treatment is effective. We found that 7.5 mg/kg of 2-Cl-MGV-1 can reduce the impact of the TBI as assessed by magnetic resonance imaging (MRI). We also found that 2-Cl-MGV-1 improved motor performance as observed in a treadmill test (80.9% fewer shocks needed and 40.7% more distance covered, both p < 0.05), and reduced anatomical brain damage (by 86.5%, p < 0.05), cell death (by 75.0%, p < 0.001), and microglial inflammatory response (by 50.2%, p < 0.01). The treatment also increased expression of neuronal markers NeuN and β3-tubulin (30.0%, p < 0.01; 36.0%, p < 0.01, respectively). The time window in which we found the treatment to be effective was 3–11 h after TBI. Our study suggests that agents active at the TSPO can significantly attenuate the outcome of TBI, including in the structural, cellular, and neuro-behavioral dimensions. The mechanisms involved in the attenuation of brain damage following TBI may be related to a decrease in cell death and to anti-inflammatory activity. TSPO seems to be a novel target for the development of agents aimed at the suppression of neurodegenerative processes. Full article

Background: Paclitaxel (PTX), a crucial microtubule-stabilising agent in cancer treatment, is limited by its adverse effects and hydrophobic nature, which necessitate the use of toxic solvents. This study proposes a novel approach combining PTX with new microtubule-destabilising compounds at low, safe doses that are ineffective when used individually. Objective: The aim was to evaluate the therapeutic efficacy of combining PTX with previously described pyridine (S1, S22) and benzofuran derivatives (13b, 14), which have demonstrated promising anticancer properties by inhibiting microtubule polymerisation. Methods: The PrestoBlue assay was used to determine the optimal concentrations of each compound, enabling synergistic interactions with a low dose of PTX in HeLa cervical cancer cells. The combined effects of the compounds and PTX on apoptosis, cell cycle distribution, and mitotic spindle formation were then evaluated. Results: The results showed that compounds 13b (1 µM), 14 (0.1 µM), S1 (2 µM), and S22 (2 µM) enhanced the proapoptotic and antimitotic effects of 1 nM PTX, which was ineffective alone. Notably, live-cell imaging revealed that the concurrent use of S1 and PTX produced effects similar to those of a higher PTX concentration (5 nM). Conclusions: These findings suggest that these compounds enhance the anticancer efficacy of low-dose PTX, potentially paving the way for more effective and safer cancer therapies. Full article

Background/Objectives: The synthesis of (E)-1-(1,3-diphenylallyl)-1H-1,2,4-triazoles and related compounds as anti-mitotic agents with activity in breast cancer was investigated. These compounds were designed as hybrids of the microtubule-targeting chalcones, indanones, and the aromatase inhibitor letrozole. Methods: A panel of 29 compounds was synthesized and examined by a preliminary screening in estrogen receptor (ER) and progesterone receptor (PR)-positive MCF-7 breast cancer cells together with cell cycle analysis and tubulin polymerization inhibition. Results: (E)-5-(3-(1H-1,2,4-triazol-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-1-en-1-yl)-2-methoxyphenol 22b was identified as a potent antiproliferative compound with an IC₅₀ value of 0.39 mM in MCF-7 breast cancer cells, 0.77 mM in triple-negative MDA-MB-231 breast cancer cells, and 0.37 mM in leukemia HL-60 cells. In addition, compound 22b demonstrated potent activity in the sub-micromolar range against the NCI 60 cancer cell line panel including prostate, melanoma, colon, leukemia, and non-small cell lung cancers. G₂/M phase cell cycle arrest and the induction of apoptosis in MCF-7 cells together with inhibition of tubulin polymerization were demonstrated. Immunofluorescence studies confirmed that compound 22b targeted tubulin in MCF-7 cells, while computational docking studies predicted binding conformations for 22b in the colchicine binding site of tubulin. Compound 22b also selectively inhibited aromatase. Conclusions: Based on the results obtained, these novel compounds are suitable candidates for further investigation as antiproliferative microtubule-targeting agents for breast cancer. Full article

Phytopathogenic oomycetes, particularly Phytophthora capsici, the causal agent of Phytophthora blight disease in essential vegetables and fruit crops, remains a persistent challenge in the vegetable production industry. However, the core molecular regulators of the pathophysiology and broad-range host characteristics of P. capsici remain unknown. Here, we used transcriptomics and CRISPR-Cas9 technology to functionally characterize the contributions of a novel gene (PcTBCC1) coding for a hypothetical protein with a tubulin-binding cofactor C domain with a putative chloroplast-targeting peptide (cTP) to the pathophysiological development of P. capsici. We observed significant upregulation in the expression of PcTBCC1 during pathogen–host interactions. However, the vegetative growth of the ∆Pctbcc1 strains was not significantly different from the wild-type strains. PcTBCC1 gene replacement significantly compromised the sporulation, pathogenic differentiation, and virulence of P. capsici. At the same time, ∆Pctbcc1 strains were sensitive to cell wall stress-inducing osmolytes. These observations, coupled with the close evolutionary ties between PcTBCC1 and pathogenic oomycetes and algae, partly support the notion that PcTBCC1 is a conserved determinant of pathogenesis. This study provides insights into the significance of tubulin-binding cofactors in P. capsici and underscores the potential of PcTbcc1 as a durable target for developing anti-oomycides to control phytopathogenic oomycetes. Full article

Background and aim: Chamomile tea, renowned for its exquisite taste, has been appreciated for centuries not only for its flavor but also for its myriad health benefits. In this study, we investigated the preventive potential of chamomile (Matricaria chamomilla L.) towards cancer by focusing on its anti-inflammatory activity. Methods and results: A virtual drug screening of 212 phytochemicals from chamomile revealed β-amyrin, β-eudesmol, β-sitosterol, apigenin, daucosterol, and myricetin as potent NF-κB inhibitors. The in silico results were verified through microscale thermophoresis, reporter cell line experiments, and flow cytometric determination of reactive oxygen species and mitochondrial membrane potential. An oncobiogram generated through comparison of 91 anticancer agents with known modes of action using the NCI tumor cell line panel revealed significant relationships of cytotoxic chamomile compounds, lupeol, and quercetin to microtubule inhibitors. This hypothesis was verified by confocal microscopy using α-tubulin-GFP-transfected U2OS cells and molecular docking of lupeol and quercetin to tubulins. Both compounds induced G2/M cell cycle arrest and necrosis rather than apoptosis. Interestingly, lupeol and quercetin were not involved in major mechanisms of resistance to established anticancer drugs (ABC transporters, TP53, or EGFR). Performing hierarchical cluster analyses of proteomic expression data of the NCI cell line panel identified two sets of 40 proteins determining sensitivity and resistance to lupeol and quercetin, further pointing to the multi-specific nature of chamomile compounds. Furthermore, lupeol, quercetin, and β-amyrin inhibited the mRNA expression of the proinflammatory cytokines IL-1β and IL6 in NF-κB reporter cells (HEK-Blue Null1). Moreover, Kaplan–Meier-based survival analyses with NF-κB as the target protein of these compounds were performed by mining the TCGA-based KM-Plotter repository with 7489 cancer patients. Renal clear cell carcinomas (grade 3, low mutational rate, low neoantigen load) were significantly associated with shorter survival of patients, indicating that these subgroups of tumors might benefit from NF-κB inhibition by chamomile compounds. Conclusion: This study revealed the potential of chamomile, positioning it as a promising preventive agent against inflammation and cancer. Further research and clinical studies are recommended. Full article

Alternatively spliced tissue factor (asTF) promotes the progression of pancreatic ductal adenocarcinoma (PDAC) by activating β1-integrins on PDAC cell surfaces. hRabMab1, a first-in-class humanized inhibitory anti-asTF antibody we recently developed, can suppress PDAC primary tumor growth as a single agent. Whether hRabMab1 has the potential to suppress metastases in PDAC is unknown. Following in vivo screening of three asTF-proficient human PDAC cell lines, we chose to make use of KRAS G12V-mutant human PDAC cell line PaCa-44, which yields aggressive primary orthotopic tumors with spontaneous spread to PDAC-relevant anatomical sites, along with concomitant severe leukocytosis. The experimental design featured orthotopic tumors formed by luciferase labeled PaCa-44 cells; administration of hRabMab1 alone or in combination with gemcitabine/paclitaxel (gem/PTX); and the assessment of the treatment outcomes on the primary tumor tissue as well as systemic spread. When administered alone, hRabMab1 exhibited poor penetration of tumor tissue; however, hRabMab1 was abundant in tumor tissue when co-administered with gem/PTX, which resulted in a significant decrease in tumor cell proliferation; leukocyte infiltration; and neovascularization. Gem/PTX alone reduced primary tumor volume, but not metastatic spread; only the combination of hRabMab1 and gem/PTX significantly reduced metastatic spread. RNA-seq analysis of primary tumors showed that the addition of hRabMab1 to gem/PTX enhanced the downregulation of tubulin binding and microtubule motor activity. In the liver, hRabMab1 reduced liver metastasis as a single agent. Only the combination of hRabMab1 and gem/PTX eliminated tumor cell-induced leukocytosis. We here demonstrate for the first time that hRabMab1 may help suppress metastasis in PDAC. hRabMab1’s ability to improve the efficacy of chemotherapy is significant and warrants further investigation. Full article

Background and Objectives: Tirbanibulin 1% ointment is a novel synthetic anti-proliferative agent that inhibits tubulin polymerization. It is approved for treating actinic keratosis (AK) on the face and scalp in adults. It has demonstrated good efficacy, an adequate safety profile and excellent patient adherence in the phase 3 clinical trials, however data about its real-life efficacy and safety are lacking. Here we report the experience of the dermatology unit of the University Hospital of Messina. Materials and Methods: We performed a spontaneous open-label, prospective non-randomized study to assess the effectiveness and safety of tirbanibulin 1% ointment for the treatment of 228 AKs in 38 consecutive patients—28 males (73%) and 10 females (26%)—aged between 52 and 92 years (mean age: 72 ± 8.92 years). Results: Total clearance was recorded in 51% of lesions, while partial clearance was recorded in 73% of lesions. An excellent tolerability profile and high compliance rate were observed, with no treatment discontinuation due to the onset of adverse events. Conclusion: Our real-life experience confirms the effectiveness and safety of tirbanibulin ointment for the treatment of AKs. Full article

Antimitotic agents are one of the more successful types of anticancer drugs, but they suffer from toxicity and resistance. The application of approved drugs to new indications (i.e., drug repurposing) is a promising strategy for the development of new drugs. It relies on finding pattern similarities: drug effects to other drugs or conditions, similar toxicities, or structural similarity. Here, we recursively searched a database of approved drugs for structural similarity to several antimitotic agents binding to a specific site of tubulin, with the expectation of finding structures that could fit in it. These searches repeatedly retrieved frentizole, an approved nontoxic anti-inflammatory drug, thus indicating that it might behave as an antimitotic drug devoid of the undesired toxic effects. We also show that the usual repurposing approach to searching for targets of frentizole failed in most cases to find such a relationship. We synthesized frentizole and a series of analogs to assay them as antimitotic agents and found antiproliferative activity against HeLa tumor cells, inhibition of microtubule formation within cells, and arrest at the G₂/M phases of the cell cycle, phenotypes that agree with binding to tubulin as the mechanism of action. The docking studies suggest binding at the colchicine site in different modes. These results support the repurposing of frentizole for cancer treatment, especially for glioblastoma. Full article

Tubulin-targeting agents attract undiminished attention as promising compounds for the design of anti-cancer drugs. Verubulin is a potent tubulin polymerization inhibitor, binding to colchicine-binding sites. In the present work, a series of verubulin analogues containing a cyclohexane or cycloheptane ring 1,2-annulated with pyrimidine moiety and various substituents in positions 2 and 4 of pyrimidine were obtained and their cytotoxicity towards cancer and non-cancerous cell lines was estimated. The investigated compounds revealed activity against various cancer cell lines with IC₅₀ down to 1–4 nM. According to fluorescent microscopy data, compounds that showed cytotoxicity in the MTT test disrupt the normal cytoskeleton of the cell in a pattern similar to that for combretastatin A-4. The hit compound (N-(4-methoxyphenyl)-N,2-dimethyl-5,6,7,8-tetrahydroquinazolin-4-amine) was encapsulated in biocompatible nanocontainers based on Ca²⁺ or Mg²⁺ cross-linked alginate and it was demonstrated that its cytotoxic activity was preserved after encapsulation. Full article

Bio-control agents are the best alternative to chemicals for the successful management of plant diseases. Among them, Trichoderma is commonly used as a biological control agent in plant disease management due to its ability to suppress soil-borne plant pathogens. In the present study, 20 Trichoderma asperellum isolates were collected from different geographical locations and confirmed using morphological characteristics and molecular phylogenetic inferences based on combined ITS and β-tubulin sequences. All twenty isolates were screened for their antagonism against the collar rot pathogen under in vitro and in planta conditions. The isolates were evaluated through dual culture and volatile methods in an in vitro study. Isolate A10 inhibited the test pathogen Agroathelia rolfsii at 94.66% in a dual culture assay and 70.95% in a volatile assay, followed by the isolates A11 and A17, which recorded 82.64% and 81.19% in dual culture assay and 63.75% and 68.27% in the volatile assay respectively. An in planta study was conducted under greenhouse conditions in tomato var. pusa ruby by pre- and post-inoculation of T. asperellum isolates in the A. rolfsii infected soil to evaluate their antagonistic potential against the disease. The A10 isolate was found effective under both pre- and post-inoculation conditions, with a disease inhibition percent of 86.17 and 80.60, respectively, followed by the isolates A11 and A17, which exhibited inhibition of 77.80% and 75.00% in pre-inoculation and 72.22% and 69.44% in post-inoculation, respectively. Further, biochemical analysis was conducted to determine the specific activity of hydrolytic enzymes produced by T. asperellum during interaction with A. rolfsii. We found that isolate A10 produces more hydrolytic enzymes with the specific activity of 174.68 IU/mg of β-1,3 glucanase, 183.48 IU/mg of β-1, 4 glucanase, 106.06 IU/mg of protease, followed by isolate A17, A11 respectively. In GC-MS analysis, we observed maximum anti-microbial volatile organic compounds from the isolate A10, including 2H-Pyran-2-one (17.39%), which was found to be most abundant, followed by dienolactone (8.43%), α-pyrone (2.19%), and harziandione (0.24%) respective retention time of 33.48, 33.85, 33.39, and 64.23 min, respectively, compared to other isolates. In the TLC assay, we observed that a greater number of bands were produced by the A10 and A17 isolates in the Hexane: Ethyl Acetate (1:1) solvent system than in the 9:1 solvent system, which represents the presence of major metabolites in the ethyl acetate extract. Full article

Avermectins are a group of macrocyclic lactones that are commonly used as pesticides to treat pests and parasitic worms. Some members of the avermectin family, such as ivermectin, have been found to exhibit anti-proliferative activity toward cancer cells. This study aimed to investigate the potential anti-cancer activities of avermectin B1a using the HCT-116 colon cancer cell line. The MTT assay was used to calculate the IC₅₀ by incubating cells with increasing doses of avermectin B1a for 24, 48, and 72 h. Flow cytometry was used to evaluate apoptosis following the 24 h incubation of cells. The migration capacity of the HCT-116 cells in the absence or presence of avermectin B1a was also investigated. Finally, tubulin polymerization in the presence of avermectin B1a was evaluated. Avermectin B1a presented anti-proliferative activity with an IC₅₀ value of 30 μM. Avermectin B1a was found to promote tubulin polymerization at 30 μM. In addition, avermectin B1a induced apoptosis in HCT-116 cells and substantially diminished their ability to migrate. Avermectin B1a exhibits significant anti-cancer activity and enhances tubulin polymerization, suggesting that it can be used as a promising microtubule-targeting agent for the development of future anticancer drugs. Full article

Increasing awareness of the structure of microtubules has made tubulin a relevant target for the research of novel chemotherapies. Furthermore, the particularly high sensitivity of glioblastoma multiforme (GBM) cells to microtubule disruption could open new doors in the search for new anti-GBM treatments. However, the difficulties in developing potent anti-tubulin drugs endowed with improved pharmacokinetic properties necessitates the expansion of medicinal chemistry campaigns. The application of an ensemble pharmacophore screening methodology helped to optimize this process, leading to the development of a new tetrazole-based tubulin inhibitor. Considering this scaffold, we have synthesized a new family of tetrazole derivatives that achieved remarkable antimitotic effects against a broad panel of cancer cells, especially against GBM cells, showing high selectivity in comparison with non-tumor cells. The compounds also exerted high aqueous solubility and were demonstrated to not be substrates of efflux pumps, thus overcoming the main limitations that are usually associated with tubulin binding agents. Tubulin polymerization assays, immunofluorescence experiments, and flow cytometry studies demonstrated that the compounds target tubulin and arrest cells at the G2/M phase followed by induction of apoptosis. The docking experiments agreed with the proposed interactions at the colchicine site and explained the structure–activity relationships. Full article

In the search for innovative approaches to cancer chemotherapy, a chemical library of 49 cyanochalcones, 1a-r, 2a-o, and 3a-p, was designed as dual inhibitors of human farnesyltransferase (FTIs) and tubulin polymerization (MTIs) (FTIs/MTIs), two important biological targets in oncology. This approach is innovative since the same molecule would be able to interfere with two different mitotic events of the cancer cells and prevent these cells from developing an emergency route and becoming resistant to anticancer agents. Compounds were synthesized by the Claisen–Schmidt condensation of aldehydes with N-3-oxo-propanenitriles under classical magnetic stirring and under sonication. Newly synthesized compounds were screened for their potential to inhibit human farnesyltransferase, tubulin polymerization, and cancer cell growth in vitro. This study allowed for the identification of 22 FTIs and 8 dual FTIs/MTIs inhibitors. The most effective molecule was carbazole-cyanochalcone 3a, bearing a 4-dimethylaminophenyl group (IC₅₀ (h-FTase) = 0.12 µM; IC₅₀ (tubulin) = 0.24 µM) with better antitubulin activity than the known inhibitors that were previously reported, phenstatin and (-)-desoxypodophyllotoxin. The docking of the dual inhibitors was realized in both the active site of FTase and in the colchicine binding site of tubulin. Such compounds with a dual inhibitory profile are excellent clinical candidates for the treatment of human cancers and offer new research perspectives in the search for new anti-cancer drugs. Full article