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Eukaryotic elongation factor 2 kinase (eEF-2K) is an unusual alpha kinase involved in protein synthesis through phosphorylation of elongation factor 2 (EF2). eEF-2K is highly overexpressed in breast cancer, and its activity is associated with significantly shortened patient survival and proven to be a potential molecular target in breast cancer. The crystal structure of eEF-2K remains unknown, and there is no potent, safe, and effective inhibitor available for clinical applications. We designed and synthesized several generations of potential inhibitors. The effect of the inhibitors at the binding pocket of eEF-2K was analyzed after developing a 3D target model by using a domain of another ?-kinase called myosin heavy-chain kinase A (MHCKA) that closely resembles eEF-2K. In silico studies showed that compounds with a coumarin-chalcone core have high predicted binding affinities for eEF-2K. Using in vitro studies in highly aggressive and invasive (MDA-MB-436, MDA-MB-231, and BT20) and noninvazive (MCF-7) breast cancer cells, we identified a lead compound that was highly effective in inhibiting eEF-2K activity at submicromolar concentrations and at inhibiting cell proliferation by induction of apoptosis with no toxicity in normal breast epithelial cells. In vivo systemic administration of the lead compound encapsulated in single lipid-based liposomal nanoparticles twice a week significantly suppressed growth of MDA-MB-231 tumors in orthotopic breast cancer models in nude mice with no observed toxicity. In conclusion, our study provides a highly potent and in vivo effective novel small-molecule eEF-2K inhibitor that may be used as a molecularly targeted therapy breast cancer or other eEF-2K-dependent tumors. © 2021 American Chemical Society. 1R01CA244344; University of Texas MD Anderson Cancer Center; Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, TÜBITAK: 215S008, TUBITAK-BIDEB 2214A This study was funded by The Scientific and Technological Research Council of Turkey (TUBITAK) (grant number 215S008 and TUBITAK-BIDEB 2214A program, F.C.O.) and The University of Texas-MD Anderson Cancer Center Bridge fund (B.O. and N.K.) and NIH-NCI 1R01CA244344 grants (B.O. and N.K.).

Great strides have been made in triple negative breast cancer (TNBC) treatment, which represents 20% of total predicted annual US breast cancer (BC) cases. Despite the development of several therapeutics, TNBC patients have poor overall survival rate, compared to other BC patients, justifying the urgent need to discover new entities for use to control TNBC. Chalcones are important natural products with diverse bioactivities including anticancer effects. This study aimed to design, synthesize and validate novel chalcone leads as potential therapies for TNBC. Fourteen novel chalcone analogs were designed and synthesized comprising alicyclic amines (pyrrolidine, morpholine and piperidine) or nitrogen mustard (Bis-(2-chloroethyl) amine) substituents. Among them, compound 14 ((E)-3-(4-(Bis(2-chloroethyl) amino) phenyl)-1-(3-methoxyphenyl) prop-2-en-1-one) was identified as the most effective against TNBC and other BC phenotypes, with anti-proliferative IC50 values ranging between 3.94 and 9.22 μM against the TNBC cell lines MDA-MB-231 and MDA-MB-468, as well as against the estrogen positive MCF-7 cell line. Chalcone 14 effectively suppressed the colony formation capacity of MDA-MB-231, MDA-MB-468, and MCF-7 cell lines at 5 and 10 μM treatment concentrations. Furthermore, compound 14 has significantly inhibited cell invasion and migration of MDA-MB-231 and MCF-7 BC cell lines. Additionally, compound 14 had significantly promoted apoptosis by upregulating BAX and downregulating Bcl-2 proteins. Compound 14 induced significant cell cycle arrest of TNBC cells at the G2/M phase. It also induced a reversal of Epithelial Mesenchymal Transition (EMT) by upregulating the epithelial markers E-cadherin and Pan-cadherin and downregulating FAK. Furthermore, it had dramatically diminished new vessel formation (vasculogenesis) in chick chorioallantoic membrane (CAM) model by 60.20 ± 8.47%. Chalcone 14 inhibited 46.41 ± 0.71% of the TNBC MAD-MB-231 cells growth in a nude mouse orthotopic xenograft model in comparison with vehicle control treated animals. Collectively, this study results propose chalcone 14 as a promising lead molecule for the control of TNBC as well as other breast cancer phenotypes. This research work was supported by Grants# GCC-2017-2 and QUST-1-CPH-2018-18 from Qatar University ; and GSRA award# GSRA4-2-0418-17024 from Qatar National Research Fund (a member of Qatar Foundation). Scopus

In this work, mixed ligand complexes of Co(II) Ni(II) and Cu(II) were synthesized using quercetin and diimine (1,10-phenanthroline or 2,2 '-bipyiridine) ligands. The obtained Ni(II) and Co(II) complexes are new and the Cu(II) complexes are synthesized by different method from the literature. The characterization of complexes was performed by elemental analysis, thermogravimetric analysis, ESI-MS, UV-visible and infrared spectral analyses, magnetic susceptibility and molar conductivity measurements. It was found that quercetin, diimine and metal(II) ion form 1:1:1 complexes. Resulting data supported octahedral geometry for Ni(II) and Co(II) complexes and square pyramidal geometry for Cu(II) complexes. The proposed compositions are [Co(queH-1)Cl(phen)(H2O)]center dot 2H(2)O (1, queH = quercetin, phen = 1,10-phenanthroline), [Ni(queH-1)Cl(phen)(H2O)]center dot 2H(2)O (2), [Cu(queH-1)Cl(phen)]center dot 2.5H(2)O (3) and [Cu(queH-1)Cl(bpy)]center dot 2H(2)O (4, bpy = 2,2 '-bipyiridine). Antioxidant capacity and total phenolic content of complexes measured by Folin-Ciocalteu and ABTS methods. Anti-cancer effect of these compounds were tested against different cancer cells (A549, PC-3, HeLa and MCF-7). Apoptosis identified by the fluorescence imaging, caspase cleaved cytokeratin-18 and flow cytometry analysis (annexin V, caspase 3/7, mitochondria membrane potential and oxidative stress). As a result, Cu(II) complexes are more effective than the other compounds and Complex 3 is a promising anti-cancer compound against breast cancer MCF-7 and MDA-MB-231 cells (IC50 values are 2.4 and 5.4 mu M for 48 h, respectively). Flow cytometry analysis exhibited that Complex 3 caused apoptosis in MCF-7 cells. These results support that Complex 3 has anticancer activity and can be a potential anticancer agent especially in breast cancer. WOS:000519936700015 31832781 Q2

Propolis has been used in folk medicine for centuries due to its healing properties. Ethanolic extracts of propolis (EEP) are rich sources of phenolic acid and flavonoids. Natural phenolic compounds may exert chemoprotective activity in cancer cells due to their ability to scavenge free radicals. The aim of this in vitro study was to investigate the genotoxic and anti-mutagenic effects of the EEP on human peripheral blood lymphocytes (PBLs) and their cytotoxic potential on the human breast cancer cell line (MDA-MB-231 cells). Both cell cultures were treated with six concentrations (1, 10, 50, 100, 250 and 500 μg/ml) of EEP1 and EEP2, separately and in combination with mitomycin C (MMC). Our results show that the EEP1 and EEP2 samples of propolis after separate and combined treatments with MMC did not influence the nuclear division index (NDI). In the combined treatment, both tested EEPs significantly reduced MMC-induced micronuclei (MN) in PBLs. At 48 h after exposure of the MDA-MB-231 cell line to a combined treatment of EEP samples with MMC, the IC50 values were significantly reduced (23.79 and 19.13 μg/ml, for EEP1+MMC and EEP2+MMC, respectively, in comparison to the single treatment. In conclusion, the tested ethanolic extracts of propolis exhibited a certain level of in vitro antimutagenic activity in PBLs from healthy subjects, and anticancer activity in breast cancer cell line. The presented findings suggest that the ethanolic extracts of propolis show potential in anticancer therapeutic strategy. [Projekat Ministarstva nauke Republike Srbije, br. III41010]

The main aim of this study is to assess the safety and antitumor efficacy of a palladium(II) (Pd)-saccharinate complex with terpyridine. To characterize the Pd(II) complex in vitro, its cytotoxicity was evaluated using a water-soluble tetrazolium salt cell viability assay and the mechanism of cell death was assessed by DNA fragmentation/condensation and live cell imaging analyses. The antitumor efficacy and safety of the Pd(II) complex in-vivo were examined by analyzing reduction in tumor size, changes in body and organ weight, histopathological analysis of liver, kidney, and tumor sections, and biochemical analysis of serum in C57BL/6 mice. Our results showed that the Pd(II) complex was more cytotoxic to cancer cells than noncancer cell lines and caused cell death through apoptotic pathways. The treatment of the Pd(II) complex in tumor-bearing mice effectively reduced the tumor size at half the dose used for cisplatin. The Pd(II) complex appeared to exert less liver damage than the cisplatin-based complex on changes in the hepatic enzymes levels in the serum. Hence, the complex appears to be a potential chemotherapeutic drug with high antitumor efficacy and fewer hepatotoxic complications, providing an avenue for further studies. Anti-Cancer Drugs 28: 898-910 Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved. Scientific and Technological Research Institute of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) This work was supported by the internal funding of The Scientific and Technological Research Institute of Turkey (TUBITAK). WOS:000408162400009 28657910 Q3

Objectives: Palladium complexes are potent and less toxic molecules in comparison to other metal based agents. Here, we characterized two palladium(II) saccharinate complexes with terpyridine for their cell cycle specificity. Materials and methods: Cells were arrested at Gl, Gl/S boundary or mitosis using mimosine, double-Thymidine block, aphidicolin, nocodazole or colcemid, and evaluated based on morphology and flow cytometry. Synchronized cells were treated with the Pd(II) complexes, and viability was measured via MTT assay. Results: While treatment of arrested cells with the Pd(II) complexes resulted in no significant change in cell death in HCT-116 and MDA-MB-231 cells, HeLa cells were more sensitive in S/G1. The main form of cell death was found to be apoptosis. Conclusions: Pd(II) complexes appear to be cell-cycle non-specific, while cell line dependent differences may be observed. Cells die through apoptosis regardless of the cell cycle stage, which makes these complexes more promising as anti-cancer agents. İstanbul Üniversitesi - 36696

Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase, has anti-tumor properties in various carcinoma models. Diisopropylamine dichloroacetate (DADA), an over-the-counter drug for chronic liver disease, is a derivative of DCA. To date, few studies have evaluated the anticancer potential of DADA in breast cancer. In this study, MDA-MB-231 cells, a breast adenocarcinoma cell line, were used in in vitro and in vivo experiments to evaluate the anti-tumor efficacy of DADA and DCA. The half maximal inhibitory concentration (IC50) of DADA (7.1 ± 1.1 mmol/L) against MDA-MB-231 cells was significantly lower than that of DCA (15.6 ± 2.0 mmol/L); 100 mg/kg (0.0004 mol/kg) DADA was better than 100 mg/kg (0.0008 mol/kg) DCA at suppressing the growth of subcutaneous transplantation breast tumor at the same dose after 24 days intervention. Histological examination showed that both DCA and DADA interventions led to necrosis, inflammation, and fibrosis of tumor tissue in a mouse subcutaneous transplantation breast tumor model. DADA treatment inhibited Ki67 expression in tumor tissue. In vitro experiments showed that DADA could inhibit lactic acid production and glucose uptake in MDA-MB-231 cells at 10 mmol/L and these effects were stronger than DCA. DADA administration also induced complete autophagy during early treatment stages and incomplete autophagy and cell death at later treatment stages. In conclusion, DADA showed better anti-tumor efficacy than DCA in a breast cancer model.

The control of micrometastatic breast cancer remains problematic. To this end, we are developing a new adjuvant therapy based on (213)Bi-PAI2, in which an alpha-emitting nuclide ((213)Bi) is chelated to the plasminogen activator inhibitor-2 (PAI2). PAI2 targets the cell-surface receptor bound urokinase plasminogen activator (uPA), which is involved with the metastatic spread of cancer cells. We have successfully labelled and tested recombinant human PAI2 with the alpha radioisotope (213)Bi to produce (213)Bi-PAI2, which is highly cytotoxic towards breast cancer cell lines. In this study, the 2-day postinoculation model, using MDA-MB-231 breast cancer cells, was shown to be representative of micrometastatic disease. Our in vivo efficacy experiments show that a single local injection of (213)Bi-PAI2 can completely inhibit the growth of tumour at 2 days postcell inoculation, and a single systemic (i.p.) administration at 2 days causes tumour growth inhibition in a dose-dependent manner. The specific role of uPA as the target for (213)Bi-PAI2 therapy was determined by PAI2 pretreatment blocking studies. In vivo toxicity studies in nude mice indicate that up to 100 microCi of (213)Bi-PAI2 is well tolerated. Thus, (213)Bi-PAI2 is successful in targeting isolated breast cancer cells and preangiogenic cell clusters. These results indicate the promising potential of (213)Bi-PAI2 as a novel therapeutic agent for micrometastatic breast cancer.