Exploring the potential of Ziziphus nummularia and luteolin-7-O-glucoside as tubulin inhibitors in cancer therapy and survival.

Cancer is responsible for approximately 10 million deaths worldwide, with 70% of the deaths occurring in low- and middle-income countries; as such safer and more effective anti-cancer drugs are required. Therefore, the potential benefits of Ziziphus nummularia and Ziziphus spina-christi as sources of anti-cancer agents were investigated. Z. nummularia and Z. spina-christi extracts were prepared using chloroform, ethanol, ethyl acetate, and water. The extracts' anti-cancer properties were determined using the MTT Cell Viability Assay in four cancer cell lines: breast (KAIMRC2 and MDA-MB-231), colorectal (HCT8), and liver (HepG2). The ApoTox-Glo Triplex Assay and high-content imaging (HCI)-Apoptosis Assay were used to assess KAIMRC2 and HCT8 cells further. In addition, KAIMRC2 cells were tested for microtubule staining, and AKT/mTOR protein expression was determined by western blot analysis. Liquid chromatography-mass spectrometry (LC-MS) was performed to identify the secondary metabolites in the ethanol and ethyl acetate extracts, followed by in silico techniques to predict molecular targets and interactions, safety, and pharmacokinetic profile for identified metabolites. Out of the eight extracts, the ethanolic extract of Z. nummularia, exhibited the most potent activity against KAIMRC2 cells with an IC50 value of 29.2 µg/ml. Cancer cell treatment with the ethanolic extract of Z. nummularia resulted in a dose-dependent decrease in cell viability with increased apoptosis and cytotoxic effects. Microtubule staining showed a disrupted microtubular network. The ethanolic extract treatment of KAIMRC2 cells led to upregulated expression of pAKT and pmTOR. In silico studies predicted luteolin-7-O-glucoside to be a ligand for tubulin with the highest docking score (- 7.686) and similar binding interactions relative to the native ligand. Further computational analysis of the metabolites showed acceptable pharmacokinetic and safety profiles, although ethanolic extract metabolites were predicted to have cardiotoxic effects. Ethanolic extraction is optimal for solubilizing active anticancer metabolites from Z. nummularia, which may act by causing M-phase arrest via inhibition of tubulin polymerization. Luteolin-7-O-glucoside is the lead candidate for further research and development as an anti-cancer agent. In addition, this study suggests that herbal treatment could switch on mechanisms of adaptation and survival in cancer cells.

Design of novel isoxazole derivatives as tubulin inhibitors using computer-aided techniques: QSAR modeling, in silico ADMETox, molecular docking, molecular dynamics, biological efficacy, and retrosynthesis.

In the current work, computational methods were used to investigate new isoxazole derivatives that could be used as tubulin inhibitors. The study aims to develop a reliable quantitative structure-activity relationship (QSAR) model, following the criteria set by Golbraikh, Tropsha, and Roy. As a result, seven candidate compounds were developed, all having higher activity than the well-established anticancer agent Cisplatin (Cisp). According to the ADMETox in silico test, the candidates Pr4, Pr5, and P6 can be toxic. As a result, we have chosen to focus our study on compounds Pr1, Pr2, and Pr3. Molecular docking analysis revealed that drug candidate Pr2 exhibits the highest stability within the oxidized quinone reductase 2 (PDB ID: 4zvm), target receptor (ΔG(Pr2) = ΔG(Pr3) = -10.4 < ΔG(Pr1) = -10.0 < ΔG(Cisp) = -7.3 kcal/mol). This finding aligns with the activity predictions made by the QSAR model. Furthermore, molecular dynamics simulations of the Pr2-4zvm complex over 100 ns confirm the ligand's robust stability within the receptor's active site, supporting the results obtained from molecular docking and the QSAR model predictions. The CaverDock software was utilized to identify the tunnels likely to be followed by ligands moving from the active site to the receptor surface. This analysis also helped in determining the biological efficacy of the target compounds. The results indicated that the Pr2 compound is more effective than the others. Finally, the computer-assisted retrosynthesis process of two high confidence sequences was used to synthesize drug candidates.Communicated by Ramaswamy H. Sarma.

3D-QSAR methods were used to design eight new compounds and anti-tubulin agents.3D-QSAR models were validated by Golbraikh­Tropsha and Roy methods.The toxicity and pharmacokinetics of the proposed compounds were identified by the Lipinski rule of five, Veber rules, and ADMETox.Pr2 and Pr3 had a reasonable affinity to the receptor protein (ID PDB: 4zvm) based on molecular docking, reactivity indices, and molecular dynamics simulation.Metadynamics was used to study ligand transport in the receptor (ID PDB:3zvm).

Bioprocessing of Epothilone B from Aspergillus fumigatus under solid state fermentation: Antiproliferative activity, tubulin polymerization and cell cycle analysis.

Epothilone derivatives have been recognized as one of the most powerful anticancer drugs towards solid tumors, for their unique affinity to bind with ß-tubulin microtubule arrays, stabilizing their disassembly, causing cell death. Sornagium cellulosum is the main source for Epothilone, however, the fermentation bioprocessing of this myxobacteria is the main challenge for commercial production of Epothilone. The metabolic biosynthetic potency of epothilone by Aspergillus fumigatus, an endophyte of Catharanthus roseus, raises the hope for commercial epothilone production, for their fast growth rate and feasibility of manipulating their secondary metabolites. Thus, nutritional optimization of A. fumigatus for maximizing their epothilone productivity under solid state fermentation process is the objective. The highest yield of epothilone was obtained by growing A. fumigatus on orange peels under solid state fermentation (2.2 µg/g), bioprocessed by the Plackett-Burman design. The chemical structure of the extracted epothilone was resolved from the HPLC and LC-MS/MS analysis, with molecular mass 507.2 m/z and identical molecular fragmentation pattern of epothilone B of S. cellulosum. The purified A. fumigatus epothilone had a significant activity towards HepG2 (IC50 0.98 µg/ml), Pancl (IC50 1.5 µg/ml), MCF7 (IC50 3.7 µg/ml) and WI38 (IC50 4.6 µg/ml), as well as a strong anti-tubulin polymerization activity (IC50 0.52 µg/ml) compared to Paclitaxel (2.0 µg/ml). The effect of A. fumigatus epothilone on the immigration ability of HepG2 cells was assessed, as revealed from the wound closure of the monolayer cells that was estimated by ~ 63.7 and 72.5%, in response to the sample and doxorubicin, respectively, compared to negative control. From the Annexin V-PI flow cytometry results, a significant shift of the normal cells to the apoptosis was observed in response to A. fumigatus epothilone by ~ 20 folds compared to control cells, with the highest growth arrest of the HepG2 cells at the G0-G1 stage.

Anthraquinones from the roots of Morinda scabrida Craib exhibit antiproliferative activity against A549 lung cancer cells and antitubulin polymerization.

Six anthraquinones were isolated from Morinda scabrida Craib, an unexplored species of Morinda found in the tropical forest of Thailand. All six anthraquinones showed cytotoxicity against A549 lung cancer cells, with the most active compound, nordamnacanthal (MS01), exhibiting the IC50 value of 16.3 ± 2.5 µM. The cytotoxic effect was dose-dependent and led to cell morphological changes characteristic of apoptosis. In addition, flow cytometric analysis showed dose-dependent apoptosis induction and the G2/M phase cell cycle arrest, which was in agreement with the tubulin polymerization inhibitory activity of MS01. Molecular docking analysis illustrated the binding between MS01 and the α/ß-tubulin heterodimer at the colchicine binding site, and UV-visible absorption spectroscopy revealed the DNA binding capacity of MS01.

Microtubule destabilising activity of selected 7-methoxy-2-phenylbenzo[b]furan derivative against primary and metastatic melanoma cells.

Herein, we report the results of anticancer screening of two 2-phenylbenzo[b]furan derivatives functionalised at the 3-position with 4-hydroxy-3,5-dimethoxybenzoyl (BF2) or 3,4,5-trimethoxybenzoyl (BF3) against 60 different cancer cell lines. The results confirmed the anticancer potential of the tested compounds against different cancer cell types, especially colon cancer, brain cancer and melanoma. BF3 was defined as the most potent (also as a tubulin polymerisation inhibitor). Its anticancer activity against melanoma cell lines that originated from different stages, i.e., primary skin-derived A375 and metastatic WM9/MDA-MB-435S, was evaluated (as the clinical success of melanoma therapy strictly depends on the disease stage). Moreover, to determine the BF3 mode of action and its effect on cell proliferation, intracellular microtubule networks, cell cycle phase distribution and apoptosis were evaluated. Our study revealed that BF3 inhibited cell proliferation in a dose-dependent manner, with IC50 yielding 0.09 ± 0.01 µM, 0.11 ± 0.01 µM and 0.18 ± 0.05 µM for A375, MDA-MB435S and WM9, respectively. The strong antiproliferative activity of compound BF3 correlated well with its inhibitory effect on tubulin polymerisation. Molecular docking proved that BF3 belongs to the colchicine binding site inhibitors (CBSIs), and experimental studies revealed that it disturbs cell cycle progression leading to G2/M arrest and apoptosis.

Design and preparation of pH-sensitive cytotoxic liposomal formulations containing antitumor colchicine analogues for target release.

Herein, we describe the synthesis of pH-sensitive lipophilic colchicine prodrugs for liposomal bilayer inclusion, as well as preparation and characterization of presumably stealth PEGylated liposomes with above-mentioned prodrugs. These formulations liberate strongly cytotoxic colchicinoid derivatives selectively under slightly acidic tumor-associated conditions, ensuring tumor-targeted delivery of the compounds. The design of the prodrugs is addressed to pH-triggered release of active compounds in the slight acidic media, that corresponds to tumor microenvironment, while keeping sufficient stability of the whole formulation at physiological pH. Correlations between the structure of the conjugates, their hydrolytic stability, colloidal stability, ability of the prodrug retention in the lipid bilayer are described. Several formulations were found promising for further development and in vivo investigations.

Identification of 1,3,4-oxadiazoles as tubulin-targeted anticancer agents: a combined field-based 3D-QSAR, pharmacophore model-based virtual screening, molecular docking, molecular dynamics simulation, and density functional theory calculation approach.

Cancer is one of the most prominent causes of death worldwide and tubulin is a crucial protein of cytoskeleton that maintains essential cellular functions including cell division as well as cell signalling, that makes an attractive drug target for cancer drug development. 1,3,4-oxadiazoles disrupt microtubule causing G2-M phase cell cycle arrest and provide anti-proliferative effect. In this study, field-based 3D-QSAR models were developed using 62 bioactive anti-tubulin 1,3,4-oxadiazoles. The best model characterized by PLS factor 7 was rigorously validated using various statistical parameters. Generated 3D-QSAR model having high degree of confidence showed favourable and unfavourable contours around 1,3,4-oxadiazole core that assisted in defining proper spatial positioning of desired functional groups for better bioactivity. A five featured pharmacophore model (AAHHR_1) was developed using same ligand library and validated through enrichment analysis (BEDROC160.9 value = 0.59, Average EF 1% = 27.05, and AUC = 0.74). Total 30,212 derivatives of 1,3,4-oxadiazole obtained from PubChem database was prefiltered through validated pharmacophore model and docked in XP mode on binding cavity of tubulin protein (PDB code: 1SA0) which led into the identification of 11 HITs having docking scores between -7.530 and -9.719 kcal/mol while the reference compound Colchicine exerted docking score of -7.046 kcal/mol. Following the analysis of MM-GBSA and ADME studies, HIT1 and HIT4 emerged as the two promising hits. To verify their thermodynamic stability at the target site, molecular dynamic simulations were carried out. Both HITs were further subjected to DFT analysis to determine their HOMO-LUMO energy gap for ensuring their biological feasibility. Finally, molecular docking based structural exploration for 1,3,4-oxadiazoles to set up a lead of Formula I for further advancements of tubulin polymerization inhibitors as anti-cancer agents.Communicated by Ramaswamy H. Sarma.

Synthesis, modeling, and biological evaluation of anti-tubulin indole-substituted furanones.

Due to the central role of tubulin in various cellular functions, it is a validated target for anti-cancer therapeutics. However, many of the current tubulin inhibitors are derived from complex natural products and suffer from multidrug resistance, low solubility, toxicity issues, and/or the lack of multi-cancer efficacy. As such, there is a continued need for the discovery and development of new anti-tubulin drugs to enter the pipeline. Herein we report on a group of indole-substituted furanones that were prepared and tested for anti-cancer activity. Molecular docking studies showed positive correlations between favorable binding in the colchicine binding site (CBS) of tubulin and anti-proliferative activity, and the most potent compound was found to inhibit tubulin polymerization. These compounds represent a promising new structural motif in the search for small heterocyclic CBS cancer inhibitors.

Insight into the Tubulin-Targeted Anticancer Potential of Noscapine and its Structural Analogs.

Cancer is known as a notorious disease responsible for threatening millions of lives every year. Natural products which act by disrupting the microtubule assembly and dynamics have proven to be highly successful as anticancer agents but their high toxicity owing to lower selectivity has limited their usage. Recently, Noscapine (NOS), a known anti-tussive, has come out to be an effective anti-tubulin candidate with far lesser toxicity. Since its first report as an anti-mitotic agent in 1998, NOS has been extensively studied and modified by various groups of researchers to optimize its anti-tubulin activity. In this review, the recent advancements about the potential of these therapeutic candidates against various cancers have been compiled and analyzed for their inhibitory mechanism in distinct health conditions. It has been observed that the non-polar substitutions (e.g., halides, aryl groups) at specific sites (9-position and N-sites of isoquinoline ring; and modification of a methoxy group) have an enhanced effect on efficacy. The mechanistic studies of NOS and its modified analogs have shown their inhibitory action primarily through interaction with microtubules dynamics thus disrupting the cell-cycle and leading to apoptosis. This review highlights the latest research in the field by providing a rich resource for the researchers to have a hands-on analysis of NOS analogs and the inhibitory action in comparison to other microtubule disrupting anti-cancer agents. The article also documents the newer investigations in studying the potential of noscapine analogs as possible anti-microbial and antiviral agents.

Development of [1,2]oxazoloisoindoles tubulin polymerization inhibitors: Further chemical modifications and potential therapeutic effects against lymphomas.

Lymphomas are among the ten most common cancers, and, although progress has been achieved in increasing survival, there is still an unmet need for more effective therapeutic approaches, including better options for patients with refractory tumors that initially respond but then relapse. The lack of effective alternative treatment options highlights the need to develop new therapeutic strategies capable of improving survival prospects for lymphoma patients. Herein, we describe the identification and exploration of the SAR of a series of [1,2]oxazolo[5,4-e]isoindoles as potent small molecules that bind to the colchicine site of tubulin and that have promise for the treatment of refractory lymphomas. Exploration of the chemical space of this class of compounds at the pyrrole moiety and at the [1,2]oxazole ring highlighted two compounds bearing a 3,5-dimethoxybenzyl and a 3,4,5-trimethoxybenzyl group as potent candidates and showed that structural modifications at the isoxazole moiety are generally not favorable for activity. The two best candidates showed efficacy against different lymphoma histotypes and displayed 88 and 80% inhibition of colchicine binding fitting well into the colchicine pocket, as demonstrated by X-ray crystallography T2R-TTL-complexes, docking and thermodynamic analysis of the tubulin-colchicine complex structure. These results were confirmed by transcriptome data, thus indicating [1,2]oxazolo[5,4-e]isoindoles are promising candidates as antitubulin agents for the treatment of refractory lymphomas.

Discovery of (2-(pyrrolidin-1-yl)thieno[3,2-d]pyrimidin-4-yl)(3,4,5-trimethoxyphenyl)methanone as a novel potent tubulin depolymerizing and vascular disrupting agent.

In this study, a series of 2-substituted thieno[3,2-d]pyrimidin-4-yl(3,4,5-trimethoxyphenyl)methanones were designed, synthesized and evaluated as novel anti-tubulin polymerization and vascular disrupting agents. A pyrrolidin-1-yl derivative, compound 20, exhibited strong antiproliferative activities (average IC50 = 13.4 nM) against four cancer cell lines. 20 also showed retained potency toward paclitaxel-resistant A549 cells. 20 could significantly inhibit tubulin polymerization with an IC50 of 1.6 µM. 20 displayed strong induction of G2/M arrest and apoptosis through the mitochondrial pathway. Dose-dependent suppression of the migration of cancer cells and the formation of a vascular network were observed after treatment with 20. The acceptable microsomal stability implied that it is worth conducting further study on the analogues of 20 as novel drug candidates of CBSIs.

Design, synthesis, biological assessment, and in-Silico studies of 1,2,4-triazolo[1,5-a]pyrimidine derivatives as tubulin polymerization inhibitors.

A series of 1,2,4-triazolo[1,5-a]pyrimidine derivatives have been designed and synthesized as combretastatin CA-4 analogs. They were screened for anticancer and tubulin polymerization inhibition activities. The trimethoxyphenyl 1,2,4-triazolo[1,5-a]pyrimidine derivative 4c showed significant antiproliferative activity in which it exhibited IC50 = 0.53 µM against HCT-116 cancer cell line. It was further tested as a tubulin polymerization inhibitor showing an IC50 = 3.84 µM if compared to combretastatin IC50 = 1.10 µM. Further mechanism studies revealed that compound 4c could obviously inhibit the proliferation of HCT-116 cancer cells by inducing apoptosis and arresting the cell cycle at the G2/M phase. Furthermore, docking studies showed that compound 4c illustrated good fitting to the colchicine binding site of tubulin. Thus, it is considered an anticancer lead compound worthy of further development as a tubulin polymerization inhibitor.

Recent Trends in Tubulin-Binding Combretastatin A-4 Analogs for Anticancer Drug Development.

Although significant progress over several decades has been evidenced in cancer therapy, there remains a need for the development of novel and effective therapeutic strategies to treat several relapsed and intractable cancers. In this regard, tubulin protein has become one of the efficient and major targets for anticancer drug discovery. Considering the antimitotic ability, several tubulin inhibitors have been developed to act against various cancers. Among various tubulin inhibitors available, combretastatin-A4 (CA-4), a naturally occurring lead molecule, offers exceptional cytotoxicity (including the drugresistant cell lines) and antivascular effects. Although CA-4 offers exceptional therapeutic efficacy, several new advancements have been proposed, in terms of structural modification via A and B rings, as well as cis-olefinic bridging, which provide highly efficient analogs with improved tubulin-binding efficiency to meet the anticancer drug development requirements. This review systematically emphasizes the recent trends and latest developments in the anticancer drug design and discovery using CA-4 analogs as the tubulin inhibiting agents by highlighting their structure-activity relationships (SAR) and resultant pharmacological efficacies.

Effect of the Marine Polyketide Plocabulin on Tumor Progression.

Marine sponges represent one of the richest sources of natural marine compounds with anticancer potential. Plocabulin (PM060184), a polyketide originally isolated from the sponge Lithoplocamia lithistoides, elicits its main anticancer properties binding tubulin, which still represents one of the most important targets for anticancer drugs. Plocabulin showed potent antitumor activity, in both in vitro and in vivo models of different types of cancers, mediated not only by its antitubulin activity, but also by its ability to block endothelial cell migration and invasion. The objective of this review is to offer a description of plocabulin's mechanisms of action, with special emphasis on the antiangiogenic signals and the latest progress on its development as an anticancer agent.

An improved synthesis of indanocine and antiproliferative activity of 2-benzylindanocine via microtubule destabilization.

Indanocine, a potent anticancer investigational drug of National Cancer Institute-USA, has been much discussed in recent years. Present communication aimed at total synthesis of indanocine and its close analogues. Total synthesis was improved by double yields than previously reported yields. Some of the benzylidene and 2-benzyl derivatives with free rotation at C2 position exhibited potential cytotoxicities against various human cancer cell lines. Five such analogues exhibited potential antiproliferative effect against HCT-116 and MIA PACA-2 cell lines. Benzylindanocine 12i induced microtubule destabilization by occupying colchicine binding pocket of ß-tubulin. It also exhibited anti-inflammatory activity by down-regulating IL-6 and TNF-α. In Ehrlich ascites carcinoma model, 12i reduced 78.4% of EAC tumour in Swiss albino mice at 90 mg/kg (i.p.) dose. Further, in in vivo safety studies, 12i was found to be safe to rodents up to 1,000 mg/kg dose. Concomitant anticancer and anti-inflammatory activity of benzylindanocine is distinctive, which suggests its further optimization for better efficacy and druggability.

Chalcone Scaffolds as Anticancer Drugs: A Review on Molecular Insight in Action of Mechanisms and Anticancer Properties.

Cancer is the deadliest disease worldwide and the development of safer chemical entities to treat cancer is one of the major challenges of medicinal chemistry. The emergence of new cases every year and the development of multiple drug resistance against available molecular entities have turned the focus of researchers towards natural products. Chalcones are pharmacologically active compounds, present in plants, which have been derivatized and screened by many researchers for the treatment of cancer. Chalcones, consist of 1,3-diaryl-2- propen-1-one, is one such class exhibiting broad anticancer activities against various cancerous cell lines. The objective of this review article is to analyze the antitumor activity of the reported chalcones via distinct mechanisms adopted by these molecules underlying their inhibitory activity. The primary focus of this review is to bring the attention of researchers towards the latest and important chalcones and their derivatives having potent anticancer activity adding their possible action of mechanisms against cancerous cell lines The recent literature was surveyed and it was found that chalcone analogs with electron donating groups, indolyl, quinolone, pyrazol-ol, hydroxyaminobenzamide, hydroxamic acid and pyridyl- indole groups have shown promise as potential anticancer agents following various mechanisms. Most chalcones were found to induce significant cell cycle arrest at G2/M phase hence leading to apoptosis. A number of synthetic chalcones exhibited higher efficacy due to their ability of potent tubulin polymerization as well as dynamic enzyme inhibitory activity. This review is an immense compilation of research regarding the mechanism of action of chalcones and their identification as a promising anticancer agent for future drug developments. Thus, this review article would pave the way and provide ample opportunities to design future generations of novel, highly efficacious anticancer molecules with minimal toxicity.

[Significance of anti-tubulin-α-1C autoantibody in systemic sclerosis].

OBJECTIVE: To detect the serum level of a novel autoantibody, anti-tubulin-α-1C, in patients with systemic sclerosis (SSc) and to investigate its clinical significance. METHODS: Anti-tubulin-α-1C antibody levels were determined by enzyme-linked immunosorbent assay (ELISA) in 62 patients with SSc, 38 systemic lupus erythematosus (SLE), 24 primary Sjögren's syndrome (pSS) patients, and 30 healthy controls (HCs). Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), immunoglobulin A(IgA), immunoglobulin M (IgM), immunoglobulin G (IgG), C3, C4, rheumatoid factor (RF), antinuclear antibody(ANA), anti-centromere antibodies(ACA), anticardiolipin (aCL), anti-dsDNA antibody, anti-Sm antibody, anti-RNP antibody, anti-Scl-70 antibody, anti-Ro52 antibody, anti-SSA antibody, anti-SSB antibody, centromere protein A(CENP-A), centromere protein B (CENP-B) were measured by standard laboratory techniques. Raynaud's phenomenon and modified Rodnan skin score(MRSS) were recorded to evaluate the disease status of SSc. Independent sample t test, Chi square test, Mann-Whitney U test, Spearman rank correlation were used for statistical analyses. RESULTS: The serum anti-tubulin-α-1C antibody concentration in SSc group was 81.24±34.38, the serum anti-tubulin-α-1C antibody concentration in SLE group was 87.84±38.52, the serum anti-tubulin-α-1C antibody concentration in pSS group was 59.79±25.24, and the serum anti-tubulin-α-1C antibody concentration in healthy group was 39.37±18.7. Multivariate analysis revealed that anti-tubulin-α-1C antibody levels were significantly increased in the SSc and SLE patients. The expression level of anti-tubulin-α-1C antibody in SSc was higher compared with the pSS group and the health control group (P < 0.01). Further analysis demonstrated that the elevated anti-tubulin-α-1C antibody were correlated with the SSc inflammation and disease activity markers ESR(r=0.313, P=0.019), The levels of anti-tubulin-α-1C antibody were also significantly correlated with MRSS(r=0.636, P < 0.01). The best cut-off value for the diagnose of SSc was 76.77 as mean+2SD value. The proportion of Raynaud's phenomenon was higher in the group of anti-tubulin-α-1C autoantibody-postive SSc patients than that in anti-tubulin-α-1C autoantibody negative group(71.4% vs. 37.5%, P=0.039). The proportions of anti-Scl-70 antibody, anti-CENP antibody and anti-cardiolipin antibody were higher in the group of anti-tubulin-α-1C autoantibody-postive SSc patients than in the anti-tubulin-α-1C autoantibody negative group (37.9% vs. 15.2%, 34.5% vs. 12.1%, 13.8 vs. 0, respectively, all P < 0.05). CONCLUSION: Based on this explorative stu-dy, the level of anti-tubulin-α-1C antibody increased in the serum of the patients with SSc. There were correlations between anti-tubulin-α-1C autoantibody and clinical and laboratory indicators of the SSc patients. It may become a novel biomarker indicative of active SSc and could be applied in future clinical practice.

Structure and function of the nervous system in nectophores of the siphonophore Nanomia bijuga.

Although the bell-shaped nectophores of the siphonophore Nanomia bijuga are clearly specialized for locomotion, their complex neuroanatomy described here testifies to multiple subsidiary functions. These include secretion, by the extensively innervated 'flask cells' located around the bell margin, and protection, by the numerous nematocytes that line the nectophore's exposed ridges. The main nerve complex consists of a nerve ring at the base of the bell, an adjacent column-shaped matrix plus two associated nerve projections. At the top of the nectophore the upper nerve tract appears to have a sensory role; on the lower surface a second nerve tract provides a motor input connecting the nectophore with the rest of the colony via a cluster of nerve cells at the stem. N. bijuga is capable of both forward and backward jet-propelled swimming. During backwards swimming the water jet is redirected by the contraction of the Claus' muscle system, part of the muscular velum that fringes the bell aperture. Contractions can be elicited by electrical stimulation of the nectophore surface, even when both upper and lower nerve tracts have been destroyed. Epithelial impulses elicited there, generate slow potentials and action potentials in the velum musculature. Slow potentials arise at different sites around the bell margin and give rise to action potentials in contracting Claus' muscle fibres. A synaptic rather than an electrotonic model more readily accounts for the time course of the slow potentials. During backward swimming, isometrically contracting muscle fibres in the endoderm provide the Claus' fibres with an immobile base.

Fluorinated benzylidene indanone exhibits antiproliferative activity through modulation of microtubule dynamics and antiangiogenic activity.

The application of fluorine in drug design has been understood significantly by the medicinal chemists in recent years. Modulation of tubulin-microtubule dynamics is one of the most effective targets for cancer chemotherapeutics. A logically designed and identified lead compound, fluorinated benzylidene indanone 1 has been extensively evaluated for cancer pharmacology. It occupied colchicine binding pocket acting as microtubule destabilizer and induced a G2/M phase arrest in MCF-7 cells. Compound 1 exerted an antiangiogenic effect in MCF-7 cells by down-regulating Vascular Endothelial Growth Factor (VEGF) and Hypoxia Inducible Factor-α (HIF-α). In in-vivo efficacy in C3H/Jax mice mammary carcinoma model, benzylidene indanone 1 reduced tumour volumes by 48.2%. Further in acute oral toxicity studies compound 1 was well tolerated and safe up to 1000 mg/kg dose in Swiss albino mice. The fluorinated benzylidene indanone 1, a new chemical entity (NCE) can further be optimized for better efficacy against breast adenocarcinoma.1.

Colchicine-Binding Site Inhibitors from Chemistry to Clinic: A Review.

It is over 50 years since the discovery of microtubules, and they have become one of the most important drug targets for anti-cancer therapies. Microtubules are predominantly composed of the protein tubulin, which contains a number of different binding sites for small-molecule drugs. There is continued interest in drug development for compounds targeting the colchicine-binding site of tubulin, termed colchicine-binding site inhibitors (CBSIs). This review highlights CBSIs discovered through diverse sources: from natural compounds, rational design, serendipitously and via high-throughput screening. We provide an update on CBSIs reported in the past three years and discuss the clinical status of CBSIs. It is likely that efforts will continue to develop CBSIs for a diverse set of cancers, and this review provides a timely update on recent developments.