Antimitotic Research Articles

A Snapshot of Selenium-enclosed Nanoparticles for the Management of Cancer.

Among the primary causes of mortality in today's world is cancer. Many drugs are employed to give lengthy and severe chemotherapy and radiation therapy, like nitrosoureas (Cisplatin, Oxaliplatin), Antimetabolites (5-fluorouracil, Methotrexate), Topoisomerase inhibitors (Etoposide), Mitotic inhibitors (Doxorubicin); such treatment is associated with significant adverse effects. Antitumor antibiotics have side effects similar to chemotherapy and radiotherapy. Selenium (Se) is an essential trace element for humans and animals, and additional Se supplementation is required, particularly for individuals deficient in Se. Due to its unique features and high bioactivities, selenium nanoparticles (SeNPs), which act as a supplement to counter Se deficiency, have recently gained worldwide attention. This study presented a safer and more economical way of preparing stable SeNPs. The researcher has assessed the antiproliferative efficiency of SeNPs-based paclitaxel delivery systems against tumor cells in vitro with relevant mechanistic visualization. SeNPs stabilized by Pluronic F-127 were synthesized and studied. The significant properties and biological activities of PTX-loaded SeNPs on cancer cells from the lungs, breasts, cervical, and colons. In one study, SeNPs were formulated using chitosan (CTS) polymer and then incorporated into CTS/citrate gel, resulting in a SeNPs-loaded chitosan/citrate complex; in another study, CTS was used in the synthesis of SeNPs and then situated into CTS/citrate gel, resulting in Se loaded nanoparticles. These formulations were found to be more successful in cancer treatment.

Effects of Indigo Carmine on Growth, Cell Division, and Morphology of Allium cepa L. Root Tip.

Indigo carmine has a variety of uses in foods, textiles, medicine, pharmaceuticals, and cosmetics. There are studies reporting the toxic potential of indigo carmine on human health and the environment. In this study, we investigated the cytogenotoxic effects of indigo carmine using apical root cells of Allium cepa. Allium cepa bulbs were subjected to four treatments with indigo carmine (0.0032, 0.0064, 0.0125, and 0.2 mg/mL) and to ultrapure water as a control. After 5 days, root growth, root length, mitotic index, mitotic inhibition, chromosomal anomalies, and cell morphology were analyzed. According to our results, a decrease in root length and mitotic index was observed at all concentrations of indigo carmine. Additionally, several types of chromosomal abnormalities were observed, such as disturbed metaphase, sticky chain metaphase, anaphase bridge, and laggard chromosomes. Moreover, histological observation indicated that indigo carmine induces alterations in various components of root tip tissue, such as deformation and alteration of the cell wall, progressive condensation of chromatin, shrinkage of the nuclei, and an increase in the number of irregularly shaped nuclei and nuclear fragments. Our results indicate that the tested concentrations of indigo carmine may have toxic effects and raise concerns about its intensive use in many fields.

Anticancer Tetrahydrocarbazoles: A Wide Journey from 2000 Till Date

Abstract: Tetrahydrocarbazoles (THCz) are widespread in numerous indole alkaloids and have been reported since time for exhibiting profound pharmacological potential. Many pharmaceuticals drugs have tetrahydrocarbazole nucleus in their structure e.g. vinca alkaloids (Vincristine, Vinblastine, Vinorelbine), Frovatriptan, (R)-Ramatroban, Ondansetron, etc. that are used in various multifactorial diseases. In this review article, the anticancer potential of tetrahydrocarbazole based derivatives has been covered, enumerating their vast journey from the year 2000 to 2021. Since the last twenty-one years, tetrahydrocarbazoles have been a matter of focus among researchers worldwide, whereby several novel tetrahydrocarbazole derivatives have been synthesized and reported for their anticancer potential against various cancer cell lines. Tetrahydrocarabzole and its derivatives have exhibited profound anticancer potential mediated via various cancer pathways like apoptosis, cell cycle arrest, microtubule inhibition, Nrf2 Modulators, DNA intercalators, pERK and pRb phosphorylation, VEGF (Vascular Endothelial Growth Factor) and TNF-α inhibition, TPSO (translocator protein), Histone Deacetylase (HDAC) Inhibitors also discussed. The present review entails the synthesis, SAR studies, and anticancer mechanism of tetrahydrocarbazoles derivatives reported in review literature till date, and would provide a strong database to the medicinal chemist world over in discovering newer potential anticancer agent against various types of cancer diseases.

Male meiotic spindle poles are stabilized by TACC3 and cKAP5/chTOG differently from female meiotic or somatic mitotic spindles in mice.

Transforming acidic acid coiled-coil protein 3 (TACC3) and cytoskeleton associated protein 5 (cKAP5; or colonic hepatic tumor overexpressed gene, chTOG) are vital for spindle assembly and stabilization initiated through TACC3 Aurora-A kinase interaction. Here, TACC3 and cKAP5/chTOG localization with monospecific antibodies is investigated in eGFP-centrin-2- expressing mouse meiotic spermatocytes. Both proteins bind spermatocyte spindle poles but neither kinetochore nor interpolar microtubules, unlike in mitotic mouse fibroblasts or female meiotic oocyte spindles. Spermatocytes do not display a liquid-like spindle domain (LISD), although fusing them into maturing oocytes generates LISD-like TACC3 condensates around sperm chromatin but sparse microtubule assembly. Microtubule inhibitors do not reduce TACC3 and cKAP5/chTOG spindle pole binding. MLN 8237 Aurora-A kinase inhibitor removes TACC3, not cKAP5/chTOG, disrupting spindle organization, chromosome alignment, and impacting spindle pole γ-tubulin intensity. The LISD disruptor 1,6-hexanediol abolished TACC3 in spermatocytes, impacting spindle bipolarity and chromosome organization. Cold microtubule disassembly and rescue experiments in the presence of 1,6-hexanediol reinforce the concept that spermatocyte TACC3 spindle pole presence is not required for spindle pole microtubule assembly. Collectively, meiotic spermatocytes without a LISD localize TACC3 and cKAP5/chTOG exclusively at spindle poles to support meiotic spindle pole stabilization during male meiosis, different from either female meiosis or mitosis.

AGCM-22, a novel cetuximab-based EGFR-targeting antibody-drug-conjugate with highly selective anti-glioblastoma efficacy

The epidermal growth factor receptor (EGFR) has received significant attention as a potential target for glioblastoma (GBM) therapeutics in the past two decades. However, although cetuximab, an antibody that specifically targets EGFR, exhibits a high affinity for EGFR, it has not yet been applied in the treatment of GBM. Antibody-drug conjugates (ADCs) utilize tumor-targeting antibodies for the selective delivery of cytotoxic drugs, resulting in improved efficacy compared to conventional chemotherapy drugs. However, the effectiveness of cetuximab as a targeted antibody for ADCs in the treatment of GBM remains uncertain. In this study, we synthesized AGCM-22, an EGFR-targeted ADC derived from cetuximab, by conjugating it with the tubulin inhibitor monomethyl auristatin E (MMAE) using our Valine-Alanine Cathepsin B cleavable linker. In vitro experiments demonstrated that AGCM-22 effectively inhibited GBM cell proliferation through increased levels of apoptosis and autophagy-related cell death, whereas cetuximab alone had no anti-GBM effects. Additionally, both mouse and human orthotopic tumor models exhibited the selective tumor-targeting efficacy of AGCM-22, along with favorable metabolic properties and superior anti-GBM activity compared to temozolomide (TMZ). In summary, this study presents a novel ADC for GBM therapy that utilizes cetuximab as the tumor-targeting antibody, resulting in effective delivery of the cytotoxic drug payload.

Autotetraploid Induction of Three A-Genome Wild Peanut Species, Arachis cardenasii, A. correntina, and A. diogoi.

A-genome Arachis species (AA; 2n = 2x = 20) are commonly used as secondary germplasm sources in cultivated peanut breeding, Arachis hypogaea L. (AABB; 2n = 4x = 40), for the introgression of various biotic and abiotic stress resistance genes. Genome doubling is critical to overcoming the hybridization barrier of infertility that arises from ploidy-level differences between wild germplasm and cultivated peanuts. To develop improved genome doubling methods, four trials of various concentrations of the mitotic inhibitor treatments colchicine, oryzalin, and trifluralin were tested on the seedlings and seeds of three A-genome species, A. cardenasii, A. correntina, and A. diogoi. A total of 494 seeds/seedlings were treated in the present four trials, with trials 1 to 3 including different concentrations of the three chemical treatments on seedlings, and trial 4 focusing on the treatment period of 5 mM colchicine solution treatment of seeds. A small number of tetraploids were produced from the colchicine and oryzalin gel treatments of seedlings, but all these tetraploid seedlings reverted to diploid or mixoploid states within six months of treatment. In contrast, the 6-h colchicine solution treatment of seeds showed the highest tetraploid conversion rate (6-13% of total treated seeds or 25-40% of surviving seedlings), and the tetraploid plants were repeatedly tested as stable tetraploids. In addition, visibly and statistically larger leaves and flowers were produced by the tetraploid versions of these three species compared to their diploid versions. As a result, stable tetraploid plants of each A-genome species were produced, and a 5 mM colchicine seed treatment is recommended for A-genome and related wild Arachis species genome doubling.

First total synthesis, antitumor evaluation and target identification of mornaphthoate E: A new tubulin inhibitor template acting on PI3K/Akt signaling pathway

Mornaphthoate E (MPE) is a prenylated naphthoic acid methyl ester isolated from the roots of a famous Chinese medicinal plant Morinda officinalis and shows remarkable cytotoxicity against several human tumor cell lines. In the current project, the first total synthesis of (±)-MPE was achieved in seven steps and 5.6% overall yield. Then the in vitro anti-tumor activity of MPE was first assessed for both enantiomers in two breast cancer cells, with the levoisomer exerting slightly better potency. The in vivo anti-tumor effect was further verified by applying the racemate in an orthotopic autograft mouse model. Notably, MPE exerted promising anti-metastasis activity both in vitro and in vivo and showed no obvious toxicity on mice at the therapeutic dosage. Mechanistic investigations demonstrated that MPE acted as a tubulin polymerization stabilizer and disturbed the dynamic equilibrium of microtubules via regulating PI3K/Akt signaling. In conclusion, our work has provided a new chemical template for the future design and development of next-generation tubulin-targeting chemotherapies.

3-Amide-β-carbolines block the cell cycle by targeting CDK2 and DNA in tumor cells potentially as anti-mitotic agents

β-Carboline alkaloids are natural and synthetic products with outstanding antitumor activity. C3 substituted and dimerized β-carbolines exert excellent antitumor activity. In the present research, 37 β-carboline derivatives were synthesized and characterized. Their cytotoxicity, cell cycle, apoptosis, and CDK2- and DNA-binding affinity were evaluated. β-Carboline monomer M3 and dimer D4 showed selective activity and higher cytotoxicity in tumor cells than in normal cells. Structure-activity relationships (SAR) indicated that the amide group at C3 enhanced the antitumor activity. M3 blocked the A549 (IC50 = 1.44 ± 1.10 μM) cell cycle in the S phase and inhibited A549 cell migration, while D4 blocked the HepG2 (IC50 = 2.84 ± 0.73 μM) cell cycle in the G0/G1 phase, both of which ultimately induced apoptosis. Furthermore, associations of M3 and D4 with CDK2 and DNA were proven by network pharmacology analysis, molecular docking, and western blotting. The expression level of CDK2 was downregulated in M3-treated A549 cells and D4-treated HepG2 cells. Moreover, M3 and D4 interact with DNA and CDK2 at sub-micromolar concentrations in endothermic interactions caused by entropy-driven adsorption processes, which means that the favorable entropy change (ΔS > 0) overcomes the unfavorable enthalpy change (ΔH > 0) and drives the spontaneous reaction (ΔG < 0). Overall, these results clarified the antitumor mechanisms of M3 and D4 through disrupting the cell cycle by binding DNA and CDK2, which demonstrated the potential of M3 and D4 as novel antiproliferative drugs targeting mitosis.

Development of a Novel DNA Mono-alkylator Platform for Antibody-Drug Conjugates.

Although microtubule inhibitors (MTI) remain a therapeutically valuable payload option for antibody-drug conjugates (ADC), some cancers do not respond to MTI-based ADCs. Efforts to fill this therapeutic gap have led to a recent expansion of the ADC payload "toolbox" to include payloads with novel mechanisms of action such as topoisomerase inhibition and DNA cross-linking. We present here the development of a novel DNA mono-alkylator ADC platform that exhibits sustained tumor growth suppression at single doses in MTI-resistant tumors and is well tolerated in the rat upon repeat dosing. A phosphoramidate prodrug of the payload enables low ADC aggregation even at drug-to-antibody ratios of 5:1 while still delivering a bystander-capable payload that is effective in multidrug resistant (MDR)-overexpressing cell lines. The platform was comparable in xenograft studies to the clinical benchmark DNA mono-alkylator ADC platform DGN459 but with a significantly better tolerability profile in rats. Thus, the activity and tolerability profile of this new platform make it a viable option for the development of ADCs.

Synthesis, characterization of novel N-(4-cyano-1,3-oxazol-5-yl)sulfonamide derivatives and in vitro screening their activity against NCI-60 cancer cell lines.

A novel series of N-(4-cyano-1,3-oxazol-5-yl)sulfonamides have been synthesized and characterized by IR, 1 H NMR, 13 C NMR spectroscopy, elemental analysis and chromato-mass-spectrometry. The anticancer activities of all newly synthesized compounds were evaluated via a single high-dose assay (10 μM) against 60 cancer cell lines by the National Cancer Institute (USA) according to its screening protocol. Among them, compounds 2 and 10 exhibited the highest activity against the 60 cancer cell lines panel in the one-dose assay. Compounds 2 and 10 showed inhibitory activity within the GI50 parameter and in five dose analyses. However, their cytostatic activity was only observed against some cancer cell lines, and cytotoxic concentration was outside the maximum used, i. e., >100 μM. The COMPARE analysis showed that the average graphs of the tested compounds have a moderate positive correlation with compounds with the L-cysteine analog and vinblastine (GI50 ) as well as paclitaxel (TGI), which target microtubules. Therefore, disruption of microtubule formation may be one of the mechanisms of the anticancer activity of the tested compounds, especially since among tubulin inhibitors with antitumor activity, compounds with an oxazole motif are widely represented. Therefore, N-(4-cyano-1,3-oxazol-5-yl)sulfonamides may be promising for further functionalization to obtain more active compounds.

Non-mitotic proliferation of malignant cancer cells revealed through live-cell imaging of primary and cell-line cultures

IntroductionAnti-mitosis has been a key strategy of anti-cancer therapies, targeting at a fundamental property of cancer cells, their non-controllable proliferation due to overactive mitotic divisions. For improved anti-cancer therapies, it is important to find out whether cancer cells can proliferate independent of mitosis and become resistant to anti-mitotic agents.ResultsIn this study, live-cell imaging was applied to both primary-cultures of tumor cells, and immortalized cancer cell lines, to detect aberrant proliferations. Cells isolated from various malignant tumors, such as Grade-III hemangiopericytoma, atypical meningioma, and metastatic brain tumor exhibit distinct cellular behaviors, including amoeboid sequestration, tailing, tunneling, nucleic DNA leakage, as well as prokaryote-like division such as binary fission and budding-shedding, which are collectively referred to and reported as ‘non-mitotic proliferation’ in this study. In contrast, benign tumors including Grade-I hemangiopericytoma and meningioma were not obvious in such behaviors. Moreover, when cultured in medium free of any anti-cancer drugs, cells from a recurrent Grade-III hemangiopericytoma that had been subjected to pre-operation adjuvant chemotherapy gradually shifted from non-mitotic proliferation to abnormal mitosis in the form of daughter number variation (DNV) and endomitosis, and eventually regular mitosis. Similarly, when treated with the anti-cancer drugs Epirubicin or Cisplatin, the cancer cell lines HeLa and A549 showed a shift from regular mitosis to abnormal mitosis, and further to non-mitosis as the dominant mode of proliferation with increasing drug concentrations. Upon removal of the drugs, the cells reversed back to regular mitosis with only minor occurrences of abnormal mitosis, accompanied by increased expression of the stem cell markers ALDH1, Sox, Oct4 and Nanog.ConclusionsThe present study revealed that various types of malignant, but not benign, cancer cells exhibited cellular behaviors indicative of non-mitotic proliferation such as binary fission, which was typical of prokaryotic cell division, suggesting cell level atavism. Moreover, reversible transitions through the three modes of proliferation, i.e., mitosis, abnormal mitosis and non-mitosis, were observed when anticancer drug concentrations were grossly increased inducing non-mitosis or decreased favoring mitosis. Potential clinical significance of non-mitotic proliferation in cancer drug resistance and recurrence, and its relationship with cancer stem cells are worthy of further studies.

A pharmacovigilance study on antibody-drug conjugate (ADC)-related neurotoxicity based on the FDA adverse event reporting system (FAERS).

Background: Antibody-drug conjugates (ADCs) are a relatively new class of anticancer agents that use monoclonal antibodies to specifically recognize tumour cell surface antigens. However, off-target effects may lead to severe adverse events. This study evaluated the neurotoxicity of ADCs using the FDA Adverse Event Reporting System (FAERS) database. Research design and methods: Data were extracted from the FAERS database for 2004 Q1 to 2022 Q4. We analysed the clinical characteristics of ADC-related neurological adverse events (AEs). We used the reporting odds ratio (ROR) and proportional reporting ratio (PRR) for the disproportionality analysis to evaluate the potential association between AEs and ADCs. Results: A total of 562 cases of neurological AEs were attributed to ADCs. The median age was 65years old [(Min; Max) = 3; 92]. Neurotoxic signals were detected in patients receiving brentuximab vedotin, enfortumab vedotin, polatuzumab vedotin, trastuzumab emtansine, gemtuzumab ozogamicin, inotuzumab ozogamicin, and trastuzumab deruxtecan. The payloads of brentuximab vedotin, enfortumab vedotin, polatuzumab vedotin, and trastuzumab emtansine were microtubule polymerization inhibitors, which are more likely to develop neurotoxicity. We also found that brentuximab vedotin- and gemtuzumab ozogamicin-related neurological AEs were more likely to result in serious outcomes. The eight most common ADC-related nervous system AE signals were peripheral neuropathy [ROR (95% CI) = 16.98 (14.94-19.30), PRR (95% CI) = 16.0 (14.21-18.09)], cerebral haemorrhage [ROR (95% CI) = 9.45 (7.01-12.73), PRR (95% CI) = 9.32 (6.95-12.50)], peripheral sensory neuropathy [ROR (95% CI) = 47.87 (33.13-69.19), PRR (95% CI) = 47.43 (32.93-68.30)], polyneuropathy [ROR (95% CI) = 26.01 (18.61-36.33), PRR (95% CI) = 25.75 (18.50-35.86)], encephalopathy [ROR (95% CI) = 5.16 (3.32-8.01), PRR (95% CI) = 5.14 (3.32-7.96)], progressive multifocal leukoencephalopathy [ROR (95% CI) = 22.67 (14.05-36.58), PRR (95% CI) = 22.52 (14.01-36.21)], taste disorder [ROR (95% CI) = 26.09 (15.92-42.76), PRR (95% CI) = 25.78 (15.83-42.00)], and guillain barrier syndrome [ROR (95% CI) = 17.844 (10.11-31.51), PRR (95% CI) = 17.79 (10.09-31.35)]. The mortality rate appeared to be relatively high concomitantly with AEs in the central nervous system. Conclusion: ADCs may increase the risk of neurotoxicity in cancer patients, leading to serious mortality. With the widespread application of newly launched ADC drugs, combining the FAERS data with other data sources is crucial for monitoring the neurotoxicity of ADCs. Further studies on the potential mechanisms and preventive measures for ADC-related neurotoxicity are necessary.

Successful in vitro germination of Rubus genotypes induced to polyploidy using three different antimitotic agents

Successful in vitro germination of <i>Rubus</i> genotypes induced to polyploidy using three different antimitotic agents

Abstract B030: ABC101-1, a novel microtubule inhibitor antibody-drug conjugate targeting HER2, has potent anti-tumor activity in a breast cancer model

Abstract Background: ABC101-1 is an antibody-drug conjugate (ADC) targeting receptor tyrosine-protein kinase erbB-2, also known as HER2. ABC101-1 consists of a humanized IgG1 monoclonal antibody called trastuzumab conjugated to a microtubulin inhibitor, DM1, through interchain cysteines with a drug-to-antibody ratio (DAR) of 8. Our novel non-cleavable linker platform using maleimide as a connector enabled the construction of homogeneous ABC101-1 with DAR of 8, via a straightforward process resulting in high conjugation yield. Employing non-cleavable linkers may ensure that the cytotoxic drug is delivered stably to tumor cells, enhancing the therapeutic efficacy of ADC. Herein, we describe anti-breast cancer activity through in vitro cytotoxicity and in vivo efficacy, pharmacokinetics, and binding affinity of ABC101-1. Methods: In vitro cytotoxicity of ADC and linker-payload was evaluated by measuring cell viability using Cell Count Kit-8 (CCK8) analysis. In vivo anti-tumor activity was investigated using SKBR3 cell line-derived xenograft (CDX) model. A pharmacokinetic (PK) profile was assessed by performing indirect ELISA to determine concentrations of total mAb in the serum. The binding affinity of ABC101-1 to HER2 protein was assessed using the indirect ELISA measuring the concentrations of total mAb. Results: In this study, ABC101-1 exhibited potent in vitro cytotoxicity with picomolar activity on HER2-positive breast cancer cell line. In the CDX breast cancer model, ABC101-1 led to stronger tumor growth inhibition in both early and late phases than ado-trastuzumab emtansine (DAR 3.5) at the same dose. Also, the favorable pharmacokinetic profile of ABC101-1 was observed, along with the preserved antigen-binding ability upon the conjugation to linker-payload. Conclusions: ABC101-1 displayed preclinical efficacy in in vitro and in vivo studies as well as a favorable PK, thereby suggesting its therapeutic potential as an anti-tumor drug in breast cancer therapy. This study would reveal that our novel linker platform is a promising and efficient strategy to develop effective and homogeneous ADCs with DAR 8. Our finding may support the further pre-clinical evaluation of ABC101-1. Citation Format: Seo Woo Kim, Hana Yu, Geon Ho Lee, Tae Gyu Lim, Minji Jeong, Hyeonjoo Hwang, Jee Eun Moon, Yong Beom Lee, Sung-Ha Jin, Jin Hyun Jeong. ABC101-1, a novel microtubule inhibitor antibody-drug conjugate targeting HER2, has potent anti-tumor activity in a breast cancer model [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B030.

An Insight into Synthetic Strategies, SAR Study and Anticancer Mechanism of Chalcone Derivatives: Medicinal Chemistry Perspective.

Chalcone derivatives continue to captivate medicinal chemists due to their modest chemistry, facile synthetic method, and promising biological activities. They have become wellknown in the therapeutic and pharmaceutical industries due to their diverse biological actions. These complexes offer different features and applications in a human biological system due to the flexibility of the reactions, including antimicrobial, antineoplastic, antimalarial, and other uses. As a result, chalcones have sparked much attention in malignancy research. Cancer is characterized by uncontrollably growing and spreading abnormal cells and aberrant cell behavior. These masses destroy surrounding normal tissue and can attack vital organs, leading to widespread disease. Cancer is frequently used as a warning sign for impending patient death. In the age of pharmaceutical chemistry, it is unavoidably a cause for concern and a growing weight on the populace. The pathophysiology of all malignancies is due to faulty genes that regulate the development, division, and death of cells. Various genetic and environmental variables combine to cause mutations in genes encoding essential cell-regulatory proteins, leading to the numerous alterations that characterize the evolution of cancers. Rather than directly targeting DNA synthesis, the new generation of anticancer medications target signals that promote or control the cell cycle, growth factors and their receptors, signal transduction pathways, and pathways impacting DNA repair and death. Drug hunters are focusing their attention on chalcone derivatives with varying chemical structures since they are essential in the search for anticancer drugs. Chalcone's anticancer action may be attributed to molecular changes such as drug efflux protein activities, activation of apoptosis, DNA and mitochondrial damage, inhibition of angiogenesis, tubulin inhibition, and kinase inhibition. Chalcones are used to diagnose cancer as well. The development of chalcone congeners as a prodrug or prime chemical to combat cancer necessitates a thorough investigation. This review gives an update on the different pharmacological activities of natural and synthesized chalcones in recent years. Furthermore, the structure- activity connections and processes are extensively documented, providing essential design and synthesis assistance in the future.

Unveiling proteomic diversity: A quantitative study of antibody drug conjugate and chemotherapy targets in gastroesophageal cancer.

261 Background: Gastroesophageal cancer (GEC), is a significant global health concern with a 5-year relative survival of 7% for metastatic GEC. Standard treatments often include surgery, chemotherapy, and radiation therapy, but their effectiveness can be limited. Chemotherapy is frequently utilized in the treatment of GEC, although no biomarkers for chemotherapy are used in the selection of the chemo agent. There are several well-known biomarkers of resistance and sensitivity for various chemo agents. We used targeted proteomics to quantify protein expression levels of several protein biomarkers associated with chemotherapy efficiency in 125 GEC patients. These include resistance markers for platinum agents (ERCC1), and tubulin inhibitors (TUBB3). It also includes sensitivity markers for irinotecan/topotecan (Topo1), and doxorubicin/etoposide (Topo2A). We also assessed the protein levels of several antibodies-drug conjugate markers (EGFR, Her2, Trop2, FR-alpha, Mesothelin, Axl, CLDN18.2, and Nectin-4). Methods: FFPE tumor tissues from 125 clinical GC patients were microdissected and solubilized for mass spectrometry-based targeted proteomic analysis in our CLIA-certified laboratory. 72 proteins were quantified from 2-3 sections of FFPE tissue. Results: 5-Fluorouracil (5-FU), taxanes, and platinum agents (such as carboplatin) are among the chemotherapy agents that are frequently used to treat GEC. TYMP, a sensitivity marker for 5-FU, was expressed in 32% of GEC cases. ERCC1, a resistance marker for platinum drugs, was expressed at 34%. Additionally, 48% of GEC exhibited TUBB3, a resistance marker for paclitaxel and docetaxel. Topoisomerase 1 (Topo1) is the target for irinotecan or topotecan, and is also the target for some ADCs (e.g. trastuzumab deruxtecan, sacituzumab govitecan etc.). Topo1 was expressed in 92% of GEC with a 10x range (415 - 4195 amol/μg). Another topoisomerase, Topo2A, targetable by etoposide, epirubicin, and doxorubicin, was expressed in 59% of GEC with 19x range (402-7804 amol/μg). ADC targets, such as EGFR (82% detected with 184x range of distribution), Her3 (18%, 4x), AXL (18%,7x), MET (27%, 19x), and Trop2 (50%, 57x) showed a wide range of protein expression. With a 56x range (318 - 17786 amol/μg), Her2 was found in 46% of GEC, of which 12% of GEC had overexpression of Her2 (&gt;740 amol/μg), suggesting that the majority of GEC has low levels of Her2 (318-690 amol/μg), which is potentially targetable by newer anti-Her2 agents. Conclusions: Every cancer is different, and the ability to quantitate simultaneously 72 protein biomarkers from 2-3 FFPE sections provides a wealth of actionable information that, when combined with other multi-omics biomarker data, will help guide clinical treatment or patient stratification for clinical trials.

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

Evaluation of ABT-751, a novel anti-mitotic agent able to overcome multi-drug resistance, in melanoma cells

PurposeDrug efflux transporter associated multi-drug resistance (MDR) is a potential limitation in the use of taxane chemotherapies for the treatment of metastatic melanoma. ABT-751 is an orally bioavailable microtubule-binding agent capable of overcoming MDR and proposed as an alternative to taxane-based therapies.MethodsThis study compares ABT-751 to taxanes in vitro, utilizing seven melanoma cell line models, publicly available gene expression and drug sensitivity databases, a lung cancer cell line model of MDR drug efflux transporter overexpression (DLKP-A), and drug efflux transporter ATPase assays.ResultsMelanoma cell lines exhibit a low but variable protein and RNA expression of drug efflux transporters P-gp, BCRP, and MDR3. Expression of P-gp and MDR3 correlates with sensitivity to taxanes, but not to ABT-751. The anti-proliferative IC50 profile of ABT-751 was higher than the taxanes docetaxel and paclitaxel in the melanoma cell line panel, but fell within clinically achievable parameters. ABT-751 IC50 was not impacted by P-gp-overexpression in DKLP-A cells, which display strong resistance to the P-gp substrate taxanes compared to DLKP parental controls. The addition of ABT-751 to paclitaxel treatment significantly decreased cell proliferation, suggesting some reversal of MDR. ATPase activity assays suggest that ABT-751 is a potential BCRP substrate, with the ability to inhibit P-gp ATPase activity.ConclusionOur study confirms that ABT-751 is active against melanoma cell lines and models of MDR at physiologically relevant concentrations, it inhibits P-gp ATPase activity, and it may be a BCRP and/or MDR3 substrate. ABT-751 warrants further investigation alone or in tandem with other drug efflux transporter inhibitors for hard-to-treat MDR melanoma.

Genotoxic effects and mitosis aberrations of chromium (VI) on root cells of Vicia faba and its molecular docking analysis

Like other heavy metals, Cr (VI) is a powerful carcinogen and mutagen agent. Its toxic effects on plants are well considered. In order to elucidate its adverse effects, the present work aims to study the mitosis aberrations of Cr (VI) on the Vicia faba root-cells and its molecular docking analysis to understand the genotoxicity mechanisms. In-vivo, Vicia faba plants were exposed to 50 and 100 μM Cr (VI) for 48 h. In-silico, molecular docking and molecular dynamics simulation were used to study the interactions between dichromate and tubulin tyrosine ligase T2R-TTL (PDBID: 5XIW) with reference to Colchicine (microtubule inhibitor). According to our results, Cr (VI) affects growth and cell division and also induces many mitosis aberrations such as chromosome sticking, anaphase/telophase bridges, lagging chromosomes and fragmentation during all phases of mitosis. On the one hand, Cr (VI) reduces mitotic index and promotes micronuclei induction. The in-silico results showed that dichromate establishes very strong bonds at the binding site of the tubulin tyrosine ligase T2R-TTL, with a binding affinity of −5.17 Kcal/Mol and an inhibition constant of 163.59 μM. These interactions are similar to those of colchicine with this protein, so dichromate could be a very potent inhibitor of this protein's activity. TTL plays a fundamental role in the tyrosination/detyrosination of tubulin, which is crucial to the regulation of the microtubule cytoskeleton. Its inhibition leads to the appearance of many morphogenic abnormalities such as mitosis aberrations. In conclusion, our data confirm the highest genotoxicity effects of Cr (VI) on Vicia faba root-cells.

Identification of new microtubule small-molecule inhibitors and microtubule-associated genes against triple negative breast cancer.

Breast cancer represents the leading cancer type and leading cause of cancer-related death among women in the world. Triple-negative breast cancer (TNBC) is a subset of breast cancer with the poorest prognosis and still lacking of effective therapeutic options. We recently screened a natural product library and identified 3 new hit compounds with selective and prominent anti-TNBC activities on different subtype of TNBC cell lines. Interestingly, all of these 3 hit compounds belong to "cytoskeletal drugs" that target tubulin and microtubule function. Our data also showed that these hit compounds showed consistently effective on TNBC cells which are resistant to those currently used antimicrotubule agents such as Paclitaxel. RNA-Sequencing analyses revealed the anti-TNBC mechanisms of these hit compounds and identified a subset of new cellular factors commonly affected by hit compounds in different subtypes of TNBC cells. Among them, we demonstrated AHCYL1 and SPG21 as new microtubule-associated proteins, which were required for TNBC cell survival with clinical implication through tissue array analysis. Our studies provide new insights into the mechanisms of TNBC pathogenesis and offer promising therapeutic directions for this aggressive breast cancer.