Reorganization of paclitaxel-stabilized microtubule arrays at mitotic entry: roles of depolymerizing kinesins and severing proteins

Paclitaxel mediates the PI3K/AKT/mTOR pathway to reduce proliferation of FLT3‑ITD+ AML cells and promote apoptosis

Acute myeloid leukemia (AML) with internal tandem duplication (ITD) mutations in the FLT3 tyrosine kinase tend to have a poor prognosis. FLT3-ITD can promote the progress of AML by activating the PI3K/AKT/mTOR pathway. Paclitaxel (PTX) is a natural anticancer drug that has been widely used in chemotherapy for multiple malignancies. The present study used the CCK-8 assay, flow cytometry, PCR and western blotting to explore the anti-leukemia effect and possible mechanisms of PTX on MV4-11 cells with the FLT3-ITD mutation and the underlying mechanism. As a result, it was found that PTX could inhibit proliferation of MV4-11 cells and promoted apoptosis by inhibiting the PI3K/AKT/mTOR pathway.

Harnessing the power of traditional Chinese medicine monomers and compound prescriptions to boost cancer immunotherapy

At present, cancer is the largest culprit that endangers human health. The current treatment options for cancer mainly include surgical resection, adjuvant radiotherapy and chemotherapy, but their therapeutic effects and long-term prognosis are unsatisfactory. Immunotherapy is an emerging therapy that has completely transformed the therapeutic landscape of advanced cancers, and has tried to occupy a place in the neoadjuvant therapy of resectable tumors. However, not all patients respond to immunotherapy due to the immunological and molecular features of the tumors. Traditional Chinese Medicine (TCM) provides a new perspective for cancer treatment and is considered to have the potential as promising anti-tumor drugs considering its immunoregulatory properties. This review concludes commonly used TCM monomers and compounds from the perspective of immune regulatory pathways, aiming to clearly introduce the basic mechanisms of TCM in boosting cancer immunotherapy and mechanisms of several common TCM. In addition, we also summarized closed and ongoing trials and presented prospects for future development. Due to the significant role of immunotherapy in the treatment of non-small cell lung cancer (NSCLC), TCM combined with immunotherapy should be emphasized in NSCLC.

CEP20 promotes invasion and metastasis of non-small cell lung cancer cells by depolymerizing microtubules

Worldwide, Lung cancer is the leading cause of cancer-related death and poses a direct health threat, non-small cell lung cancer (NSCLC) is the most common type. In this study, we demonstrated that centrosomal protein 20 (CEP20) is upregulated in NSCLC tissues and associated with cancer invasion metastasis. Notably, CEP20 depletion inhibited NSCLC cell proliferation, migration, and microtubule polymerization. Mechanistically, we discovered that CEP20 is critical in the development of NSCLC by regulating microtubule dynamics and cell adhesion-related signaling pathways. Furthermore, the knockdown or overexpression of CEP20 affects microtubule polymerization in A549 cell lines. Our research provides a promising therapeutic target for the diagnosis and treatment of lung cancer, as well as a theoretical and experimental basis for clinical application.

Synergistic effect of Hsp90 inhibitor ginkgolic acids C151 combined with paclitaxel on nasopharyngeal carcinoma

OBJECTIVES

Nasopharyngeal cracinoma is a kind of head and neck malignant tumor with high incidence and high mortality. Due to the characteristics of local recurrence, distant metastasis, and drug resistance, the survival rate of patients after treatment is not high. Paclitaxel (PTX) is used as a chemotherapy drug in treating nasopharyngeal carcinoma, but nasopharyngeal carcinoma cells are easy to develop resistance to PTX. Inhibition of heat shock protein 90 (Hsp90) can overcome common signal redundancy and resistance in many cancers. This study aims to investigate the anti-tumor effect of ginkgolic acids C15꞉1 (C15:1) combined with PTX on nasopharyngeal carcinoma CNE-2Z cells and the mechanisms.

METHODS

This experiment was divided into a control group (without drug), a C15:1 group (10, 30, 50, 70 μmol/L), a PTX group (5, 10, 20, 40 nmol/L), and a combination group. CNE-2Z cells were treated with the corresponding drugs in each group. The proliferation of CNE-2Z cells was evaluated by methyl thiazolyl tetrazolium (MTT). Wound-healing assay and transwell chamber assay were used to determine the migration of CNE-2Z cells. Transwell chamber was applied to the impact of CNE-2Z cell invasion. Annexin V-FITC/PI staining was used to observe the effect on apoptosis of CNE-2Z cells. The changes of proteins involved in cell invasion, migration, and apoptosis after the combination of C15꞉1 and PTX treatment were analyzed by Western blotting.

RESULTS

Compared with the control group, the C15꞉1 group and the PTX group could inhibit the proliferation of CNE-2Z cells (all P<0.05). The cell survival rates of the C15꞉1 50 μmol/L combined with 5, 10, 20, or 40 nmol/L PTX group were lower than those of the single PTX group (all P<0.05), the combination index (CI) value was less than 1, suggesting that the combined treatment group had a synergistic effect. Compared with the 50 μmol/L C15꞉1 group and the 10 nmol/L PTX group, the combination group significantly inhibited the invasion and migration of CNE-2Z cells (all P<0.05). The results of Western blotting demonstrated that the combination group could significantly down-regulate Hsp90 client protein matrix metalloproteinase (MMP)-2 and MMP-9. The results of double staining showed that compared with the 50 μmol/L C15꞉1 group and the 10 nmol/L PTX group, the apoptosis ratio of CNE-2Z cells in the combination group was higher (both P<0.05). The results of Western blotting suggested that the combination group could decrease the Hsp90 client proteins [Akt and B-cell lymphoma-2 (Bcl-2)] and increase the Bcl-2-associated X protein (Bax).

CONCLUSIONS

The combination of C15꞉1 and PTX has a synergistic effect which can inhibit cell proliferation, invasion, and migration, and induce cell apoptosis. This effect may be related to the inhibition of Hsp90 activity by C15꞉1.

Time- and Concentration-Dependent Adverse Effects of Paclitaxel on Non-Neuronal Cells in Rat Primary Dorsal Root Ganglia

Paclitaxel is a chemotherapeutic agent used to treat a wide range of malignant tumors. Although it has anti-tumoral properties, paclitaxel also shows significant adverse effects on the peripheral nervous system, causing peripheral neuropathy. Paclitaxel has previously been shown to exert direct neurotoxic effects on primary DRG neurons. However, little is known about paclitaxel's effects on non-neuronal DRG cells. They provide mechanical and metabolic support and influence neuronal signaling. In the present study, paclitaxel effects on primary DRG non-neuronal cells were analyzed and their concentration or/and time dependence investigated. DRGs of Wister rats (6-8 weeks old) were isolated, and non-neuronal cell populations were separated by the density gradient centrifugation method. Different concentrations of Paclitaxel (0.01 µM-10 µM) were tested on cell viability by MTT assay, cell death by lactate dehydrogenase (LDH) assay, and propidium iodide (PI) assay, as well as cell proliferation by Bromodeoxyuridine (BrdU) assay at 24 h, 48 h, and 72 h post-treatment. Furthermore, phenotypic effects have been investigated by using immunofluorescence techniques. Paclitaxel exhibited several toxicological effects on non-neuronal cells, including a reduction in cell viability, an increase in cell death, and an inhibition of cell proliferation. These effects were concentration- and time-dependent. Cellular and nuclear changes such as shrinkage, swelling of cell bodies, nuclear condensation, chromatin fragmentation, retraction, and a loss in processes were observed. Paclitaxel showed adverse effects on primary DRG non-neuronal cells, which might have adverse functional consequences on sensory neurons of the DRG, asking for consideration in the management of peripheral neuropathy.

Cancer chemotherapy and beyond: Current status, drug candidates, associated risks and progress in targeted therapeutics

Cancer is an abnormal state of cells where they undergo uncontrolled proliferation and produce aggressive malignancies that causes millions of deaths every year. With the new understanding of the molecular mechanism(s) of disease progression, our knowledge about the disease is snowballing, leading to the evolution of many new therapeutic regimes and their successive trials. In the past few decades, various combinations of therapies have been proposed and are presently employed in the treatment of diverse cancers. Targeted drug therapy, immunotherapy, and personalized medicines are now largely being employed, which were not common a few years back. The field of cancer discoveries and therapeutics are evolving fast as cancer type-specific biomarkers are progressively being identified and several types of cancers are nowadays undergoing systematic therapies, extending patients' disease-free survival thereafter. Although growing evidence shows that a systematic and targeted approach could be the future of cancer medicine, chemotherapy remains a largely opted therapeutic option despite its known side effects on the patient's physical and psychological health. Chemotherapeutic agents/pharmaceuticals served a great purpose over the past few decades and have remained the frontline choice for advanced-stage malignancies where surgery and/or radiation therapy cannot be prescribed due to specific reasons. The present report succinctly reviews the existing and contemporary advancements in chemotherapy and assesses the status of the enrolled drugs/pharmaceuticals; it also comprehensively discusses the emerging role of specific/targeted therapeutic strategies that are presently being employed to achieve better clinical success/survival rate in cancer patients.

Secondary metabolites from endophytic fungi: Production, methods of analysis, and diverse pharmaceutical potential

The synthesis of secondary metabolites is a constantly functioning metabolic pathway in all living systems. Secondary metabolites can be broken down into numerous classes, including alkaloids, coumarins, flavonoids, lignans, saponins, terpenes, quinones, xanthones, and others. However, animals lack the routes of synthesis of these compounds, while plants, fungi, and bacteria all synthesize them. The primary function of bioactive metabolites (BM) synthesized from endophytic fungi (EF) is to make the host plants resistant to pathogens. EF is a group of fungal communities that colonize host tissues' intracellular or intercellular spaces. EF serves as a storehouse of the above-mentioned bioactive metabolites, providing beneficial effects to their hosts. BM of EF could be promising candidates for anti-cancer, anti-malarial, anti-tuberculosis, antiviral, anti-inflammatory, etc. because EF is regarded as an unexploited and untapped source of novel BM for effective drug candidates. Due to the emergence of drug resistance, there is an urgent need to search for new bioactive compounds that combat resistance. This article summarizes the production of BM from EF, high throughput methods for analysis, and their pharmaceutical application. The emphasis is on the diversity of metabolic products from EF, yield, method of purification/characterization, and various functions/activities of EF. Discussed information led to the development of new drugs and food additives that were more effective in the treatment of disease. This review shed light on the pharmacological potential of the fungal bioactive metabolites and emphasizes to exploit them in the future for therapeutic purposes.

Fabrication of a composite 3D-printed titanium alloy combined with controlled in situ drug release to prevent osteosarcoma recurrence

Osteosarcoma is a malignant bone tumor occurring in adolescents. Surgery combined with adjuvant or neoadjuvant chemotherapy is the standard treatment. However, systemic chemotherapy is associated with serious side effects and a high risk of postoperative tumor recurrence, leading to a high amputation rate and mortality in cancer patients. Implant materials that can simultaneously repair large bone defects and prevent osteosarcoma recurrence are in urgent need. Herein, an intelligent system comprising 3D-printed titanium scaffold (TS) and pH-responsive PEGylated paclitaxel prodrugs was fabricated for bone defect reconstruction and recurrence prevention following osteosarcoma surgery. The drug-loaded implants exhibited excellent stability and biocompatibility for supporting the activity of bone stem cells under normal body fluid conditions and the rapid release of drugs in response to faintly acidic environments. An in vitro study demonstrated that five human osteosarcoma cell lines could be efficiently eradicated by paclitaxel released in an acidic microenvironment. Using mice models, we demonstrated that the drug-loaded TS can enable a pH-responsive treatment of postoperative tumors and effectively prevent osteosarcoma recurrence. Therefore, local implantation of this composite scaffold may be a promising topical therapeutic method to prevent osteosarcoma recurrence.

Surface-Coated Cerium Nanoparticles to Improve Chemotherapeutic Delivery to Tumor Cells

The antioxidant property of cerium oxide nanoparticles has increased their demand as a nanocarrier to improve the delivery and therapeutic efficacy of anticancer drugs. Here, we report the synthesis of alginate-coated ceria nanoformulations (ceria NPs) and characterization using FTIR spectroscopy, Raman microscopy, and X-ray diffraction. The synthesized ceria NPs show negligible inherent in vitro toxicity when tested on a MDA-MB-231 breast cancer cell line at higher particle concentrations. Upon loading these particles with doxorubicin (Dox) and paclitaxel (PTX) drugs, we observe a potential synergistic cytotoxic effect mediated by the drug and the ceria NPs, resulting in the better killing capacity as well as suppression of cell migration against the MDA-MB-231 cell line. Further, to verify the immune-escaping capacity before targeting cancer cells, we coated the drug-loaded ceria NPs with the membrane of MDA-MB-231 cells using an extrusion method. The resultant delivery system exhibited in vitro preferential uptake by the MDA-MB-231 cell line and showed reduced uptake by the murine macrophage cell line (RAW 264.7), assigning its potential application as non-immunogenic personalized therapy in targeting and killing of cancer cells.

Stabilization of F-Actin Cytoskeleton by Paclitaxel Improves the Blastocyst Developmental Competence through P38 MAPK Activity in Porcine Embryos

Changes in F-actin distribution and cortical F-actin morphology are important for blastocyst developmental competence during embryogenesis. However, the effect of paclitaxel as a microtubule stabilizer on embryonic development in pigs remains unclear. We investigated the role of F-actin cytoskeleton stabilization via P38 MAPK activation using paclitaxel to improve the developmental potential of blastocysts in pigs. In this study, F-actin enrichment and adducin expression based on blastomere fragment rate and cytokinesis defects were investigated in cleaved embryos after in vitro fertilization (IVF). Adducin and adhesive junction F-actin fluorescence intensity were significantly reduced with increasing blastomere fragment rate in porcine embryos. In addition, porcine embryos were cultured with 10 and 100 nM paclitaxel for two days after IVF. Adhesive junction F-actin stabilization and p-P38 MAPK activity in embryos exposed to 10 nM paclitaxel increased significantly with blastocyst development competence. However, increased F-actin aggregation, cytokinesis defects, and over-expression of p-P38 MAPK protein by 100 nM paclitaxel exposure disrupted blastocyst development in porcine embryos. In addition, exposure to 100 nM paclitaxel increased the misaligned α-tubulin of spindle assembly and adhesive junction F-actin aggregation at the blastocyst stage, which might be caused by p-P38 protein over-expression-derived apoptosis in porcine embryos.

Interphase microtubule disassembly is a signaling cue that drives cell rounding at mitotic entry

At mitotic entry, reorganization of the actomyosin cortex prompts cells to round-up. Proteins of the ezrin, radixin, and moesin family (ERM) play essential roles in this process by linking actomyosin forces to the plasma membrane. Yet, the cell-cycle signal that activates ERMs at mitotic entry is unknown. By screening a compound library using newly developed biosensors, we discovered that drugs that disassemble microtubules promote ERM activation. We further demonstrated that disassembly of interphase microtubules at mitotic entry directs ERM activation and metaphase cell rounding through GEF-H1, a Rho-GEF inhibited by microtubule binding, RhoA, and its kinase effector SLK. We finally demonstrated that GEF-H1 and Ect2, another Rho-GEF previously identified to control actomyosin forces, act together to drive activation of ERMs and cell rounding in metaphase. In summary, we report microtubule disassembly as a cell-cycle signal that controls a signaling network ensuring that actomyosin forces are efficiently integrated at the plasma membrane to promote cell rounding at mitotic entry.

Paclitaxel Impedes EGFR-mutated PC9 Cell Growth via Reactive Oxygen Species-mediated DNA Damage and EGFR/PI3K/AKT/mTOR Signaling Pathway Suppression

BACKGROUND/AIM

Paclitaxel is used as a first-line and subsequent therapy for the treatment of various cancers. However, the function and mechanisms of action of paclitaxel in non-small-cell lung cancer (NSCLC) remain unknown. In this study, the molecular mechanism underlying the anticancer activity of paclitaxel was investigated in vitro in a human NSCLC cell line carrying the EGFR exon 19 deletion (PC9).

MATERIALS AND METHODS

PC9 cells were treated with paclitaxel and then evaluated with a cell viability assay, DAPI staining, Giemsa staining, apoptosis assay, reactive oxygen species (ROS) assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling assay and Western blotting.

RESULTS

Paclitaxel markedly decreased the viability of PC9 cells and induced morphological signs of apoptosis. The apoptotic effects of paclitaxel were observed through caspase cascade activation, along with ROS generation and loss of mitochondrial membrane potential (MMP). Furthermore, paclitaxel induced ROS-mediated DNA damage that triggered the activation of the extrinsic pathway of apoptosis via the up-regulation of death receptor (DR5) and caspase-8 activation. In addition, we found that paclitaxel effectively suppressed the EGFR/PI3K/AKT/mTOR signaling pathway to impede PC9 cell growth. Paclitaxel induced cell cycle arrest at the G1 phase in response to DNA damage, in association with the suppression of CDC25A, Cdk2 and Cyclin E1 protein expression.

CONCLUSION

Paclitaxel showed anticancer effects against NSCLC by activating extrinsic and intrinsic apoptotic pathways through enhancing ROS generation, inducing cell cycle arrest, and suppressing EGFR/PI3K/AKT/mTOR signaling pathway.

Transcriptome Profile Analysis of Triple-Negative Breast Cancer Cells in Response to a Novel Cytostatic Tetrahydroisoquinoline Compared to Paclitaxel

The absence of chemotherapeutic target hormone receptors in breast cancer is descriptive of the commonly known triple-negative breast cancer (TNBC) subtype. TNBC remains one of the most aggressive invasive breast cancers, with the highest mortality rates in African American women. Therefore, new drug therapies are continually being explored. Microtubule-targeting agents such as paclitaxel (Taxol) interfere with microtubules dynamics, induce mitotic arrest, and remain a first-in-class adjunct drug to treat TNBC. Recently, we synthesized a series of small molecules of substituted tetrahydroisoquinolines (THIQs). The lead compound of this series, with the most potent cytostatic effect, was identified as 4-Ethyl-N-(7-hydroxy-3,4-dihydroisoquinolin-2(1H)-yl) benzamide (GM-4-53). In our previous work, GM-4-53 was similar to paclitaxel in its capacity to completely abrogate cell cycle in MDA-MB-231 TNBC cells, with the former not impairing tubulin depolymerization. Given that GM-4-53 is a cytostatic agent, and little is known about its mechanism of action, here, we elucidate differences and similarities to paclitaxel by evaluating whole-transcriptome microarray data in MDA-MB-231 cells. The data obtained show that both drugs were cytostatic at non-toxic concentrations and caused deformed morphological cytoskeletal enlargement in 2D cultures. In 3D cultures, the data show greater core penetration, observed by GM-4-53, than paclitaxel. In concentrations where the drugs entirely blocked the cell cycle, the transcriptome profile of the 48,226 genes analyzed (selection criteria: (p-value, FDR p-value < 0.05, fold change −2< and >2)), paclitaxel evoked 153 differentially expressed genes (DEGs), GM-4-53 evoked 243 DEGs, and, of these changes, 52/153 paclitaxel DEGs were also observed by GM-4-53, constituting a 34% overlap. The 52 DEGS analysis by String database indicates that these changes involve transcripts that influence microtubule spindle formation, chromosome segregation, mitosis/cell cycle, and transforming growth factor-β (TGF-β) signaling. Of interest, both drugs effectively downregulated “inhibitor of DNA binding, dominant negative helix-loop-helix” (ID) transcripts; ID1, ID3 and ID4, and amphiregulin (AREG) and epiregulin (EREG) transcripts, which play a formidable role in cell division. Given the efficient solubility of GM-4-53, its low molecular weight (MW; 296), and capacity to penetrate a small solid tumor mass and effectively block the cell cycle, this drug may have future therapeutic value in treating TNBC or other cancers. Future studies will be required to evaluate this drug in preclinical models.

Novel pH-responsive nanohybrid for simultaneous delivery of doxorubicin and paclitaxel: an in-silico insight

BACKGROUND

The distribution of drugs could not be controlled in the conventional delivery systems. This has led to the developing of a specific nanoparticle-based delivery system, called smart drug delivery systems. In cancer therapy, innovative biocompatible nanocarriers have received much attention for various ranges of anti-cancer drugs. In this work, the effect of an interesting and novel copolymer named "dimethyl acrylamide-trimethyl chitosan" was investigated on delivery of paclitaxel and doxorubicin applying carboxylated fullerene nanohybrid. The current study was run via molecular dynamics simulation and quantum calculations based on the acidic pH differences between cancerous microenvironment and normal tissues. Furthermore, hydrogen bonds, radius of gyration, and nanoparticle interaction energies were studied here. Stimulatingly, a simultaneous pH and temperature-responsive system were proposed for paclitaxel and doxorubicin for a co-polymer. A pH-responsive and thermal responsive copolymer were utilized based on trimethyl chitosan and dimethyl acrylamide, respectively. In such a dualistic approach, co-polymer makes an excellent system to possess two simultaneous properties in one bio-polymer.

RESULTS

The simulation results proposed dramatic and indisputable effects of the copolymer in the release of drugs in cancerous tissues, as well as increased biocompatibility and drug uptake in healthy tissues. Repeated simulations of a similar article performed for the validation test. The results are very close to those of the reference paper.

CONCLUSIONS

Overall, conjugated modified fullerene and dimethyl acrylamide-trimethyl chitosan (DMAA-TMC) as nanohybrid can be an appropriate proposition for drug loading, drug delivery, and drug release on dual responsive smart drug delivery system.

Preparation of mPEG-b-PLA/TM-2 Micelle Lyophilized Products by Mixed Lyoprotectors and Antitumor Effect In Vivo

The objective of this study was to encapsulate the poorly water-soluble drug TM-2 into polymer micelles using mPEG_2k-b-PLA_2.4k to increase its aqueous solubility and improve its therapeutic effect for liver cancer. Furthermore, in order to achieve long-term storage, the micelle solution was successfully freeze-dried. This study theoretically clarified the possibility of enhancing the water solubility of TM-2 using mPEG_2k-b-PLA_2.4k micelles as well as the protective effects of mixed lyoprotectants. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM) were performed, which showed that the drug has a good affinity with the polymer (χ = 0.489) according to Flory-Huggins theory and that lyoprotectants reduced the crystallinity of PEG in mPEG_2k-b-PLA_2.4k and played a space-protective role in the lyophilization process. In vivo experiments showed that micellization could improve the drug bioavailability and give a high therapeutic effect with a tumor inhibition rate of 84.5% under the tolerated dose.

Comparison of therapeutic efficacy and mechanism of paclitaxel alone or in combination with methotrexate in a collagen-induced arthritis rat model

OBJECTIVE

To compare the therapeutic efficacy of paclitaxel (PTX) alone to its combination with methotrexate (MTX) on rheumatoid arthritis.

METHODS

A collagen-induced arthritis (CIA) rat model was established by induction of type II collagen. Rats were divided into blank control group, CIA model group, MTX group 1 mg/kg, PTX 1.5 mg/kg, PTX 2.5 mg/kg, PTX 3.5 mg/kg, and MTX 1 mg/kg + PTX 3.5 mg/kg, with 10 rats per group. The inflammation of the ankle joint was analyzed by H&E staining and interleukin (IL)-1β and IL‑6 expression was detected by immunohistochemistry. TUNEL assay was performed to detect synovial tissue cell apoptosis after administration of PTX and MTX either alone or in combination. TLR4 and p‑NF-κBp65 protein expression in synovial tissue and the changes of serum IL‑1β, IL‑6, IL‑12, MMP‑3, and TNFα protein factors were detected by western blot and ELISA, respectively.

RESULTS

PTX and MTX improved histopathological changes in CIA rats. Besides, the apoptosis rate of synovial tissue cells in the PTX 3.5 mg/kg group was more than that of the PTX + MTX group. Immunohistochemistry and western blot results indicated that PTX and MTX reduce the expression rate of IL‑6 and IL‑1β and downregulate TLR4 and p‑NF-κBp65 protein expression. Furthermore, TLR4 and p‑NF-κBp65 reduced the concentration of MMP‑3, IL‑12, IL‑6, IL1‑β, and TNFα.

CONCLUSION

Both PTX and MTX exert significant suppression on rheumatoid arthritis, and the combined effect of the two drugs is weaker than that of PTX alone. Moreover, intraperitoneal injection of PTX 3.5 mg/kg every other day was the optimal dose observed in this study.

A New Inhibitor of Tubulin Polymerization Kills Multiple Cancer Cell Types and Reveals p21-Mediated Mechanism Determining Cell Death after Mitotic Catastrophe

Induction of mitotic catastrophe through the disruption of microtubules is an established target in cancer therapy. However, the molecular mechanisms determining the mitotic catastrophe and the following apoptotic or non-apoptotic cell death remain poorly understood. Moreover, many existing drugs targeting tubulin, such as vincristine, have reduced efficacy, resulting from poor solubility in physiological conditions. Here, we introduce a novel small molecule 2-aminoimidazoline derivative—OAT-449, a synthetic water-soluble tubulin inhibitor. OAT-449 in a concentration range from 6 to 30 nM causes cell death of eight different cancer cell lines in vitro, and significantly inhibits tumor development in such xenograft models as HT-29 (colorectal adenocarcinoma) and SK-N-MC (neuroepithelioma) in vivo. Mechanistic studies showed that OAT-449, like vincristine, inhibited tubulin polymerization and induced profound multi-nucleation and mitotic catastrophe in cancer cells. HeLa and HT-29 cells within 24 h of treatment arrested in G2/M cell cycle phase, presenting mitotic catastrophe features, and 24 h later died by non-apoptotic cell death. In HT-29 cells, both agents altered phosphorylation status of Cdk1 and of spindle assembly checkpoint proteins NuMa and Aurora B, while G2/M arrest and apoptosis blocking was consistent with p53-independent accumulation in the nucleus and largely in the cytoplasm of p21/waf1/cip1, a key determinant of cell fate programs. This is the first common mechanism for the two microtubule-dissociating agents, vincristine and OAT-449, determining the cell death pathway following mitotic catastrophe demonstrated in HT-29 cells.