Search Results (77)

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/Objectives: Co-culture models of neurons and Schwann cells have been used to explore the mechanisms of myelination during development, axonal regeneration after injury, and the pathogenesis of various demyelinating neuropathies. A spontaneously immortalized Fischer rat Schwann cell line 1 (IFRS1), established from the primary culture of adult Fischer344 rat peripheral nerves, can myelinate neurites in co-cultures with primary cultured dorsal root ganglion neurons and neuronal cell lines, such as nerve growth factor (NGF)-primed PC12 cells and NSC-34 motor neuron-like cells. In this study, we aimed to establish a stable co-culture system using IFRS1 cells and ND7/23 sensory neuron-like cells. Methods: ND7/23 cells were seeded at a low density (2 × 10³/cm²) and maintained for 7 days in serum-containing medium supplemented with NGF (10 ng/mL) and the Rho kinase inhibitor Y27632 (5 μM) to promote neurite elongation. The cells were then treated with the anti-mitotic agent mitomycin C (1 μg/mL) for 12–16 h to suppress proliferative activity. Following this, the cells were co-cultured with IFRS1 cells (2 × 10⁴/cm²) and maintained at 37 °C in serum-containing medium supplemented with ascorbic acid (50 μg/mL), NGF (10 ng/mL), and ciliary neurotrophic factor (10 ng/mL). Results: Double-immunofluorescence staining performed on day 21 of the co-culture revealed myelin protein 22- or myelin basic protein-immunoreactive IFRS1 cells surrounding βIII tubulin-immunoreactive neurites emerging from ND7/23 cells. Myelin formation was further confirmed via Sudan Black B staining and electron microscopy. Conclusions: This co-culture system may provide a valuable tool for studying the processes of myelination in the peripheral nervous system, as well as the pathogenesis of various sensory neuropathies and potential novel therapeutic approaches for these conditions. 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

Triple-negative breast cancer (TNBC) is a heterogenous group of breast tumors. This type of breast tumor is relatively difficult to manage, due to the lack of expression of Hormone Receptors (HR) and human epidermal growth factor receptor (HER2). Efforts have been made to understand the factors involved in determining how a triple-negative breast tumor responds to therapy. The standard of treatment in most cases today is a combined modality of immune checkpoint inhibitors (ICIs) and chemotherapy with agents such as anti-mitotic (taxanes) or DNA-damaging agents (alkylating agents, cyclophosphamides, platin salts). In this study, we investigated the predictive and prognostic factors for TNBC, in the neoadjuvant setting; understanding each patient’s response before treatment initiation is crucial to guiding the subsequent approach and finally improving patient outcomes. We focused on tumor-infiltrating lymphocytes at the site of the primary tumor (TILs), circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), the mutational status of protein 53 (p53), and Ki-67, investigating the potential roles of these factors in predicting responses to anti-cancer agents. Full article

The production of carrot (D. carota L.) doubled haploids (DH) for the acceleration of this important vegetable crop breeding requires genome doubling of haploid regenerants. If spontaneous doubling does not occur, artificial chromosome doubling can be complicated by the lack of efficient genome-doubling protocols. We tested an antimitotic agent treatment of carrot at the embryo stage. It allowed us to produce and treat a large number of clonal carrot embryos (at least 30 embryos per treatment condition) in small volumes with minimal reagent amounts. We showed that 0.01–1 g/L colchicine did not perturb carrot development. Trifluralin showed no signs of toxicity at 0.001 and 0.01 g/L concentrations, but 0.1 g/L trifluralin reduced survival by 40% and delayed plantlet regeneration. We showed via DNA content flow cytometry that 0.01–1 g/L colchicine and 0.001–0.1 g/L trifluralin could double the carrot genome. The highest diploid percent was observed at 1 g/L colchicine (34%) and 0.1 g/L trifluralin (28%). The highest percent of diploids together with mixoploids (partial diploids) was at 0.01 and 0.1 g/L trifluralin (over 70%), followed by 1 g/L colchicine (56%). To our knowledge, this is the first report on trifluralin application for genome doubling in Apiaceae. In our study, we determined colchicine and trifluralin toxicity and doubling efficiency at different concentrations that can be used for carrot DH-line production and further improvement of genome doubling methods. Full article

Despite decades of research, cancer continues to be a disease of great concern to millions of people around the world. It has been responsible for a total of 609,820 deaths in the U.S. alone in 2023. Over the years, many drugs have been developed to remove or reduce the disease’s impact, all with varying mechanisms of action and side effects. One class of these drugs is small-molecule mitotic inhibitors. These drugs inhibit cancer cell mitosis or self-replication, impeding cell proliferation and eventually leading to cell death. In this paper, small-molecule mitotic inhibitors are discussed and classified through their discovery, underlying chemistry, and mechanism(s) of action. The binding/inhibition of microtubule-related proteins, DNA damage through the inhibition of Checkpoint Kinase 1 protein, and the inhibition of mitotic kinase proteins are discussed in terms of their anticancer activity to provide an overview of a variety of mitotic inhibitors currently commercially available or under investigation, including those in ongoing clinical trial. Clinical trials for anti-mitotic agents are discussed to track research progress, gauge current understanding, and identify possible future prospects. Additionally, antibody–drug conjugates that use mitotic inhibitors as cytotoxic payloads are discussed as possible ways of administering effective anticancer treatments with minimal toxicity. Full article

Polyploidy, characterized by an increase in the number of whole sets of chromosomes in an organism, offers a promising avenue for cannabis improvement. Polyploid cannabis plants often exhibit altered morphological, physiological, and biochemical characteristics with a number of potential benefits compared to their diploid counterparts. The optimization of polyploidy induction, such as the level of antimitotic agents and exposure duration, is essential for successful polyploidization to maximize survival and tetraploid rates while minimizing the number of chimeric mixoploids. In this study, three classification-based machine learning algorithms—probabilistic neural network (PNN), support vector classification (SVC), and k-nearest neighbors (KNNs)—were used to model ploidy levels based on oryzalin concentration and exposure time. The results indicated that PNN outperformed both KNNs and SVC. Subsequently, PNN was combined with a genetic algorithm (GA) to optimize oryzalin concentration and exposure time to maximize tetraploid induction rates. The PNN-GA results predicted that the optimal conditions were a concentration of 32.98 µM of oryzalin for 17.92 h. A validation study testing these conditions confirmed the accuracy of the PNN-GA model, resulting in 93.75% tetraploid induction, with the remaining 6.25% identified as mixoploids. Additionally, the evaluation of morphological traits showed that tetraploid plants were more vigorous and had larger leaf sizes compared to diploid or mixoploid plants in vitro. Full article

Background/Objectives: Chemoresistance of breast cancers (BCs) is a major impediment to current chemotherapeutics that urges the development of new drugs and new therapeutic approaches. To that end, phenyl 4-(2-oxo-3-alkylimidazolidin-1-yl)benzenesulfonates (PAIB-SOs) were recently prepared to fulfill some of the unmet needs with classic chemotherapeutics. PAIB-SOs are prodrugs bioactivated into potent antimitotics by the cytochrome P450 1A1 (CYP1A1), which is a frequent enzyme in resistant BC cells, but mostly missing in normal cells. Our screening program studies of PAIB-SO chemolibraries selected three prototypical PAIB-SOs as antimitotic prodrugs amenable for studies using BC animal models. Methods: Healthy female CD1^® IGS mice were treated with three prototypical PAIB-SOs, namely CEU-835, -934, and -938, for the determination of their toxicity and half-lives. Moreover, MCF7 tumor-bearing CD1-Foxn1^nu Nude female mice were treated with the three prototypical PAIB-SOs for the determination of their antitumor activity. Results: Herein, we show that multi-intravenous administrations of CEU-835, -934, and -938 at their maximal solubilities are well tolerated in healthy female CD1^® IGS mice, as depicted by the evaluation of distress behaviors, organ necropsy, total blood cell count, and histology. Moreover, the half-life of CEU-835, -934, and -938 administered intravenously in healthy CD1^® IGS female mice were 8.1, 23.2, and 21.5 h, respectively. Finally, their intravenous administrations of CEU-934 and -938 decreased MCF7 tumor growth as efficiently as paclitaxel in MCF7 tumor-bearing CD1-Foxn1^nu Nude mouse model. Conclusions: overall, our study demonstrated for the first time that pentyl-bearing PAIB-SOs are new CYP1A1-dependent prodrugs efficiently decrease breast cancer tumor growth, and show no side effects at their pharmacological concentration in mouse models. 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

The natural products combretastatins A-1 and A-4 are potent antimitotic and vascular-disrupting agents through their binding at the colchicine site in tubulin. However, these compounds suffer from a low water solubility and a tendency to isomerize to the inactive trans stilbenes. In this study, we have prepared a series of 18 cis-restricted triazole analogues of combretastatin A-4 (CA-4), maintaining, in all cases, the 3,4,5-trimethoxy phenyl ring A, with the aim of investigating the substitution pattern on the B-ring in a systematic way. To this end, cytotoxic activities of the cis-restricted analogues of CA-4 prepared were determined in two tumor cell lines, namely, HT-29 and A-549, as well as in the non-tumor cell line HEK-293, to pre-evaluate the selectivity profile of the compounds for the tumor cell lines. The main conclusion was the essential presence of methoxyl or ethoxyl groups at the para position of the B-ring in order to obtain good antitumor activities. Thus, the more active compounds in our study displayed IC₅₀ values in the nanomolar range for the tumor cell lines but not for the normal cells. Consequently, these triazole analogues of CA-4 could serve as promising alternatives to the natural product, although further studies about their biological activity are essential in order to fully determine their viability as therapeutic agents in the treatment of cancer. Full article

Brassicas are considered the third most important source of vegetable oil globally. With the escalating production of Brassica varieties, there is growing demand for high-yielding genotypes. Doubled haploid (DH) techniques have become very popular in various Brassica breeding programs. Such DH techniques can play a significant role in plant breeding by accelerating the production of homozygous lines and increasing selection efficiency. Among these methods, isolated microspore culture stands out as the most effective, facilitating the generation of a higher number of embryos compared to conventional methods of plant breeding. Different chemical compounds such as herbicides, brassinosteroids, and polyethylene glycol have an antimitotic effect and have been found to generate DH plants and improve microspore embryogenesis in Brassica species. Colchicine and trifluralin have proven to be efficient chromosome-doubling agents as well as important supplements that can increase the rate of embryogenesis. This review serves as a comprehensive summary and effectiveness evaluation of the latest research findings in the Brassica oil crops to help increase efficiency of the future research focusing on DH methods and application of antimitotic agents in the various oilseed species of the genus Brassica. Full article

Background/Objectives: The primary method used to pharmacologically arrest cancer development and its metastasis is to disrupt the cell division process. There are a few approaches that may be used to meet this objective, mainly through inhibiting DNA replication or mitosis. Despite intensive studies on new chemotherapeutics, the biggest problem remains the side effects associated with the inhibition of cell division in non-tumoural host cells. Methods: The efficacy and selectivity of the kojic acid derivative (L1) was studied in vitro with the use of tumoural (Caco2, SW480, HT29, T98G) and non- tumoural (HEK293T, RAW) cell lines. Light and electron microscopy observations were supported by the next generation sequencing (NGS), cytoflow, and spectroscopy analysis of mRNA and biomolecules, respectively. Results: The light and electron microscopy observations showed that L1 treatment leads to significant morphological changes in Caco2 cells, which are characteristic of mitosis arrest. Moreover, the fluorescent tubulin staining revealed the formation of tubulin ring structure associated with the apoptotic stage. Mitotic exit into apoptosis was further conformed by the cytoflow of early/late apoptosis stages and caspase-3 analysis. NGS investigation showed differentiated expressions of genes involved in mitosis and apoptosis processes. The observed IC50 in tumoural cell lines were as follows: Caco2 (IC50 = 68.2 mM), SW480 (IC50 = 15.5 mM), and HT29 (IC50 = 4.7 mM). Conclusions: The findings presented here suggest that L1 could be a valid candidate for oral prevention and/or chemotherapy in colorectal cancer. Considering high selectivity of L1 versus tumoural cell lines, more in-depth mechanistic studies could reveal unknown stages in carcinogenesis. Full article

Head and neck cancer (HNC), the sixth most common cancer worldwide, is increasing in incidence, with oral squamous cell carcinoma (OSCC) as the predominant subtype. OSCC mainly affects middle-aged to elderly males, often occurring on the posterior lateral border of the tongue, leading to significant disfigurement and functional impairments, such as swallowing and speech difficulties. Despite advancements in understanding OSCC’s genetic and epigenetic variations, survival rates for advanced stages remain low, highlighting the need for new treatment options. Primary treatment includes surgery, often combined with radiotherapy (RT) and chemotherapy (CT). Cetuximab-based chemotherapy, targeting the overexpressed epidermal growth factor receptor (EGFR) in 80–90% of HNCs, is commonly used but correlates with poor prognosis. Additionally, monopolar spindle 1 (MPS1), a spindle assembly checkpoint (SAC) component, is a significant target due to its role in genomic fidelity during mitosis and its overexpression in several cancers. This review explores EGFR and MPS1 as therapeutic targets in HNC, analyzing their molecular mechanisms and the effects of their inhibition on cancer cells. It also highlights the promise of combinatorial approaches, such as microtubule-targeting agents (MTAs) and antimitotic agents, in improving HNC therapies, patient outcomes, and survival rates. Full article

Many proteins regulating mitosis have emerged as targets for cancer therapy, including the kinesin spindle protein (KSP) and Aurora kinase B (AurB). KSP is crucial for proper spindle pole separation during mitosis, while AurB plays roles in chromosome segregation and cytokinesis. Agents targeting KSP and AurB selectively affect dividing cells and have shown significant activity in vitro. However, these drugs, despite advancing to clinical trials, often yield unsatisfactory outcomes as monotherapy, likely due to variable responses driven by cyclin B degradation and apoptosis signal accumulation networks. Accumulated data suggest that combining emerging antimitotics with various cytostatic drugs can enhance tumor-killing effects compared to monotherapy. Here, we investigated the impact of inhibiting anti-apoptotic signals with the BH3-mimetic Navitoclax in oral cancer cells treated with the selective KSP inhibitor, Ispinesib, or AurB inhibitor, Barasertib, aiming to potentiate cell death. The combination of BH3-mimetics with both KSP and AurB inhibitors synergistically induced substantial cell death, primarily through apoptosis. A mechanistic analysis underlying this synergistic activity, undertaken by live-cell imaging, is presented. Our data underscore the importance of combining BH3-mimetics with antimitotics in clinical trials to maximize their effectiveness. Full article