Platinum-based anticancer drugs, such as cisplatin, carboplatin, and oxaliplatin, have been approved for clinical use worldwide for decades. Despite their enormous success, their widespread application is hindered by either cross-resistance or toxic side effects, including nephrotoxicity and neurotoxicity. The need to overcome these drawbacks has stimulated the search for new platinum-based drugs. This dissertation will start with the accidental discovery of cisplatin, followed by an introduction of other platinum-based anticancer agents, including the action mechanism, general structures, and development history. Picoplatin is a newer generation of platinum-based anticancer agent. The bulky 2-methylpyridine as a non-leaving group on picoplatin could reduce the detoxification effect caused by thiol-containing species, such as glutathione and metallothionein, thus may grant picoplatin the ability to overcome cisplatin resistance. A convenient synthesis route for picoplatin derivatives has been developed. 11 new picoplatin derivatives have been designed by varying the bulkiness of the non-leaving amine group. All complexes have been characterized by different instrumentations, including MS, 1H NMR, 13C NMR, 195Pt NMR, HMQC, X-ray crystallography, and elemental analysis. Different bioassays, such as DNA binding, cell viability, and cellular accumulation, have been applied to evaluate their efficacy on cisplatin-sensitive ovarian cancer cell line A2780 and cisplatin-resistant ovarian cancer cell line A2780cis. The newly designed picoplatin derivatives show comparable efficacy with that of picoplatin and less resistance compared with cisplatin. The study of picoplatin derivatives laid the foundation toward the research of bifunctional platinum-based anticancer agents by incorporating histone deacetylase (HDAC) inhibition. Histone acetyltransferase (HAT) and histone deacetylase (HDAC) are a pair of important enzymes in epigenetic regulation. They work in harmony to acetylate and deacetylate histone lysine residues, resulting in a more relaxed or more condensed chromatin structure, respectively. HDAC has been found to be overexpressed in some cancer cells. Since 2006, 5 HDAC inhibitors (HDACi) have entered clinical use for cancer treatment. 19 new HDACi with additional coordination sites on the phenyl cap have been designed, synthesized, and evaluated. A few of the new HDACi show comparable or even better HDAC inhibition than that of Vorinostat (SAHA, the first FDA approved HDACi). A logical design would involve the installation of HDACi on the platinum center as a non-leaving group ligand. When the bifunctional drug reaches the cancer cell, the synergistic effect could be maintained as the relaxed chromatin structure makes DNA more susceptible to be attacked by the platinum centers, thus increase the anticancer activity and possibly selectivity toward cancer cells. 6 Pt-HADCi conjugates have been designed and synthesized. Dual functions of the new Pt-HDACi have been confirmed by DNA electrophoresis assay and HDAC inhibition assay. One of the Pt-HDACi (CF-101) shows comparable cytotoxicity with cisplatin and less resistance, which could be used as the lead compound for further structural modification and in vivo studies.

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Author: Katharina Zenkerová Supervisors: Assoc. Prof. PharmD. Jan Zitko, Ph.D.; Prof. Romano Silvestri Title of diploma thesis: Design and synthesis of novel 3-aroyl-1-arylpyrrole derivatives as potential tubulin polymerization inhibitors Key word: anticancer agents; pyrrole; tubulin polymerization inhibitors Cancer is a major burden of disease worldwide and it remains one of the most difficult illnesses to treat. Since the percentage of people suffering from cancer is increasing, an enormous effort to design and develop better medicaments is needed. Microtubules are a key component of the cytoskeleton in most eukaryotic cells and they represent an attractive target for antitumor agents, due to the significant mitosis rate of tumor cells. Since cancer cells usually display higher proliferation rates than normal cells, drugs that interfere with microtubules dynamic equilibrium, also known as antimitotic agents, have become a fruitful approach to develop anticancer agents in clinical use. In fact, agents interfering with microtubules may either inhibit the tubulin polymerization or block microtubules to disassembly, both causing the arrest of cell division and the consequent...

Various anticancer and antibacterial agents have been synthesized via azide chemistry by taking advantage of carbohydrate. Starting from the synthesis of 14 glycosyl azides, a library of carbohydrate-oxazolidinone conjugates and a library of carbohydrate-cyclopamine conjugates with biological interests were synthesized based on a highly efficient "click reaction" assisted by sonication. Some of the conjugates have improved solubility and enhanced anticancer activity. A library of neomycin B derivatives with various modifications at the 5" position has been synthesized. Two leads exhibit prominent activity against both methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Antibacterial activities were measured when combined with other clinically used antibiotics and significant synergistic activities were observed. Three different classes of aryl N-glycosides have been synthesized by employing 1,4-naphthoquinone and glycosyl azides undergoing a [2+3] cycloaddition. Alkyl azides can also undergo the same cycloaddition. After the removal of the protecting group, a library of 9,10-anthraquinone derivatives with potential anticancer activity and a library of 2-aminomethylene-1,3-indanediones with novel antibacterial activity have been developed, respectively. A one-pot three-component [2+3] cycloaddition for the synthesis of 1-alkyl 1H-naphtho[2,3-d][1,2,3]triazole-4,9-dione and 2-alkyl 2H-naphtho[2,3-d][1,2,3] triazole-4,9-dione has been developed. By taking the advantage of their difference in basicity, both products can be obtained in good purity. Using an allylic azide rearrangement, a convenient method has been developed for the synthesis of several 2',3'-dideoxyaminoglycosides. The antibacterial activity of these novel aminoglycosides also confirms the indispensable role of the 2'-NH2 group for both neomycin and kanamycin classes of aminoglycosides. A novel structural motif containing the hexylaminocarbonyl groups at O-5 and/or O-6 of 2',3'-dideoxyneamine could lead to the production of new aminoglycosides against resistant bacteria.

Methotrexate (MTX) is an antimetabolite anticancer agent that is used in treatment of multiple cancers, such as acute lymphoblastic leukaemia and osteosarcoma. A lack of selective tumour toxicity is one of the major problems associated with MTX chemotherapy, especially when given at high doses, as in high dose MTX (HDMTX) therapy. MTX causes various toxicity problems including life-threatening nephrotoxicity, haematological toxicity and neurotoxicity. Overcoming this toxicity is of great importance and has been attempted in various ways, not least via the design of prodrugs. The concept of tumour protease, and specifically matrix metalloproteinase (MMP), activated prodrugs was the focus of the work described in this thesis. This concept relies upon attachment of an MMP-sensitive peptide sequence to a specific site in a drug structure, so as to inactive it. The activity of the parent drug is restored once it is activated by the MMPs in the tumour microenvironment. In this work, different MMP-sensitive peptide sequences linked to MTX were synthesised, resulting in 63 MTX prodrugs. The MMP-mediated activation of these conjugates in tumour tissues (specifically HT1080 homogenates) ex vivo was assessed and the results were compared to the activation of these conjugates in various normal tissues specifically liver, kidney and lung. Specific criteria were established for the selection of promising conjugates for more detailed study. From 7 promising compounds, compound 75 was identified as the lead prodrug, demonstrating selective MMP activation, as indicated by inhibition of its activation by broad spectrum MMP inhibitor ilomastat. The pharmacokinetics of compound 75 was studied in tumour (HT1080) xenograft-bearing mice and the results were compared to those obtained from administration of equimolar doses of conventional MTX. Compound 75 led to enhanced tumour concentrations of MTX, with reduced exposure to normal tissues in vivo compared to conventional MTX therapy. Furthermore, the efficacy of equimolar doses of compound 75 and directly dosed MTX in reduction of HT1080 volume were compared. Superior antitumour activity was observed with compound 75 compared to MTX treatment. Compound 75 is the first example of an MMP-activated prodrug to be reported with enhanced therapeutic index, as evidenced by a full in vivo pharmacokinetic analysis and normal tissue metabolism data. The data presented in thesis support the concept of MMP-activated prodrug development, and form a strong foundation upon which to develop a clinically-useful MTX prodrug, with the potential to enhance efficacy and reduce toxicity to the patient. / Libyan government / The full text will be available after the extended embargo: 5th March 2027

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Thesis (MSc.(Biochemistry)) -- University of Limpopo, 2021 / Drug discovery from medicinal plants continues to play an important role in the development of anticancer agents, this is because medicinal plants are reservoirs of bioactive compounds that exert a plethora of pharmacological effects on human beings. This study aimed to analyse the phytochemical constituents of the Momordica cardiospermoides crude acetone and methanol leaf extracts as well as investigate their potential anti-metastatic effects on the MDA-MB-231 breast cancer cell line. Momordica cardiospermoides leaves were extracted with absolute methanol or acetone to produce crude methanol and acetone extracts, respectively. The extracts were then screened and analysed for phytochemicals using thin layer chromatography, qualitative and quantitative phytochemical tests, and their antioxidant activity was determined using the quantitative 2,2-diphenyl-1picrylhydrazyl (DPPH) free radical scavenging activity assay. The fingerprint profiles of the M. cardiospermoides leaf extracts revealed that compounds of the acetone extracts were optimally separated in the nonpolar mobile phase (TAE), whereas those of the methanol extract separated best in the polar mobile phase (EMW), thereby suggesting that the crude acetone and methanol extracts had more non-polar and polar compounds present, respectively. Furthermore, the qualitative phytochemical analysis indicated the presence of various phytochemicals such as flavonoids, steroids, coumarins, and tannins in both plant extracts, however, saponins were found present in the methanol extract and not in the acetone extract. Moreover, quantification of major phytochemicals revealed that the acetone extract had the highest total phenolic content (23.0683 mg GAE/g), total tannin content (22.0442 mg GAE/g) and total flavonoid (32.6933 mg QE/g) content as compared to the methanol extract (14.2349 mg GAE/g, 11.3164 mg GAE/g and 7.692 mg QE/g respectively). The DPPH free radical scavenging activity assay revealed that the extracts exhibited an increase in percentage inhibition/ DPPH scavenging effect, with an increase in extract concentration. The results also revealed that the acetone extract possessed a higher radical scavenging activity as compared to the methanol extract. These results are in correlation with the quantitative analysis of the extracts, as all the major phytochemicals found in higher amounts in the acetone extract have antioxidant properties. The extracts were then assessed in vitro for their cytotoxic effects on MDA MB-231 breast cancer cells and HEK 293 cells using the cell count and viability assay and the results obtained revealed a concentration-dependent decrease in the viability of MDA-MB-231 cells at 24 hours of treatment with either the acetone or methanol extract. Comparatively, treatment of HEK 293 cells with the acetone extract resulted in a significant decrease in the percentage of viable cells, whereas treatment with the methanol extract had no significant effect on the viability of HEK 293 cells, as the percentage of viable cells was maintained at 85–98% at 24 hours of treatment. These results also revealed that the methanol extract is more selective to cancer cells in comparison to the acetone extract, suggesting that the methanol extract is a better antineoplastic candidate. The mode of cell death induced by the methanol or acetone extracts was assessed using the acridine orange and ethidium bromide dual staining assay and the annexin V and dead cell kit. The results from the acridine orange/ethidium bromide dual staining assay showed that both extracts induced nuclei and cellular morphological changes in a concentration-depended manner, at 24 hours of treatment. Moreover, the annexin V and dead assay kit results revealed that the acetone extract induced necrotic cell death, while the methanol extract induced apoptotic cell death. Since the acetone extract was shown to be non-selective towards normal cells and induced necrotic cell death, it was discontinued for further assays. The effect of the methanol extract on MDA-MB-231 cell migration and attachment was determined using the wound healing assay and the adhesion assay. The results revealed that treatment with 150 or 300 µg/ml significantly suppressed MDA-MB-231 cell migration, associated with serpin E1 downregulation and TIMP-1 upregulation, at 24 hours of treatment. Moreover, treatment with the methanol extract also significant inhibited MDA-MB-231 cell adhesion in a concentration-dependent manner, as evident by the decrease in the number of crystal violet stained cells. The effect of the methanol extract on the expression of matrix metalloproteinase-2 and -9 was assessed using western blotting, and the results revealed that the extract significantly downregulated the expression of both MMP-2 and -9, suggesting that the methanol extract has inhibitory effects on MDA-MB-231 cell invasion. The human angiogenesis antibody array kit was then used to determine the effect of the extract on the expression of angiogenesis-related proteins. Treatment with 150 or 300 µg/ml of the extract significantly upregulated the expression levels of tissue inhibitor of metalloproteinases (TIMP) -1 and thrombospondin-1 in a concentration-dependent manner. The results also revealed a significant downregulation in the expression of serpin E1, in a concentration-dependent manner, in comparison to the untreated control. However, the expression of uPA, VEGF, and IGFBP-1, 2 and -3 was upregulated following treatment with 150 and 300 µg/ml of the extract. In conclusion, the current study demonstrated the potential of M. cardiospermoides crude methanol extract as an effective anti-metastatic agent or a source of compounds with anti-metastatic properties / South African Medical Research Council (SAMRC) Research Capacity Development Initiative and National Research Foundation (NRF)

No / PURPOSE: C-1311 is a member of the novel imidazoacridinone family of anticancer agents. This phase 1 trial was designed to investigate the safety, tolerability and preliminary anti-tumour activity of C-1311. PATIENTS AND METHODS: This was a phase 1, inter-subject dose escalating and pharmacokinetic study of intravenous (IV) C-1311, administered weekly during 3consecutive weeks followed by 1week rest (constituting 1 cycle) in subjects with advanced solid tumours. RESULTS: Twenty-two (22) patients were treated with C-1311, the highest dose given was 640mg/m(2). All subjects experienced one or more treatment-related adverse events (AEs). The most frequently observed treatment-related AEs were neutropaenia and nausea (50% each), followed by vomiting (27%), anaemia (23%), asthenia (23%) and diarrhoea (18%). Most treatment-related AEs were of Common Terminology Criteria for Adverse Events (CTCAE) grades 1-2, except for the blood and lymphatic system disorders, which were primarily of grades 3-4. The recommended dose (RD) of C-1311 administered as once weekly IV infusions for 3weeks every 4weeks is 480mg/m(2), with the dose limiting toxicity (DLT) being grade 4 neutropaenia lasting more than 7days. Treatment at this dose offers a predictable safety profile and excellent tolerability. CONCLUSION: The safety profile and preliminary anti-tumour efficacy of C-1311, observed in this broad-phase dose-finding study, warrants further evaluation of the compound.

No / The pyrrolo[2,1-c][1,4]benzodiazepines (PBDs) are a class of DNA minor groove binding agents that react covalently with guanine bases, preferably at Pu-G-Pu sites. A series of three fluorescent PBD¿coumarin conjugates with different linker architectures has been synthesized to probe correlations between DNA binding affinity, cellular localization and cytotoxicity. The results show that the linker structure plays a critical role for all three parameters. Graphical abstract A series of three fluorescent PBD¿coumarin conjugates with different linker architectures has been synthesized to probe correlations between DNA-binding affinity, cellular localization and cytotoxicity.

Yes / The complexes [RuCp*(PP)Cl] (Cp* = C5Me5; [1], PP = dppm; [4], PP = Xantphos), [RuCp#(PP)Cl] (Cp# = C5Me4(CH2)5OH; [2], PP = dppm; [5], PP = Xantphos) and [RuCp*(dppm)(CH3CN)][SbF6] [3] were synthesized and evaluated in vitro as anticancer agents. Compounds 1–3 gave nanomolar IC50 values against normoxic A2780 and HT-29 cell lines, and were also tested against hypoxic HT-29 cells, maintaining their high activity. Complex 3 yielded an IC50 value of 0.55 ± 0.03 μM under a 0.1% O2 concentration.

Targeted delivery aids in minimizing most of the drug-originated systemic toxic effects as well as improving the pharmacokinetic properties of anticancer therapeutics. Tumor targeting using hyaluronic acid (HA) as the targeting ligand has attracted a great deal of interest among a host of strategies developed to target the overexpressed tumor specific receptors. HA is an endogenous molecule that possesses a lot of biological functions in the human body. The role of HA synthases, HA degrading enzymes and the interaction of HA with its primary receptor CD44 in tumor metastasis and angiogenesis is really complex and controversial to date. However, overexpression of CD44receptors on tumor surface has been well studied, which have been utilized to direct tumor targeted drugs. Most of the HA based targeting systems were HA drug conjugates and surface modified colloidal carriers which required covalent modification. The lack of accurate structural characterization of these systems resulted in modification of HA binding sites that could affect the efficient cellular uptake. LbL technique is a simple and facile method to incorporate several materials into polyelectrolyte assemblies for drug delivery applications. HA being a negatively charged polysaccharide can be easily incorporated into such systems without any covalent modification. Although HA based polyelectrolyte multilayer films and microcapsules have been reported in combination with polycations like PAH, PLL and chitosan, their application as targeted drug delivery systems have not yet been explored. Herein, two LbL architectures with HA as the terminal layer have been investigated as targeted drug carriers, which can recognize overexpressed CD44 receptors in metastatic breast cancer cells. In the first part of the thesis, a novel polyelectrolyte nanocapsule system composed of biopolymers HA and protamine sulphate (PR) as the wall components was prepared and characterized. These pH and enzyme responsive nanocapsules were then utilized for efficient loading and release of anticancer drug doxorubicin (dox). Higher drug release was observed in simulated intracellular conditions like acidic pH and presence of hyaluronidase enzyme as compared to physiological pH. In the second part of the thesis, dox incorporated bovine serum albumin (BSA) nanoparticles modified with HA-Poly(l-Lysine) multilayers were developed and characterized. The drug release pattern of the dox loaded BSA nanoparticles was found to depend on the presence of a protease enzyme trypsin than pH variations. Both of these drug delivery systems were then evaluated for their cell targeting efficiency and cytotoxicity in CD44+ positive metastatic breast cancer cell line MDA MB 231. The final layer HA facilitated targeted delivery of these drug carriers via CD44 receptor mediated endocytosis. The enhanced cellular uptake followed by sustained delivery of dox by virtue of slow intracellular enzymatic degradation of the drug carriers resulted in their improved cytotoxicity as compared to free dox. Further in vitro biodistribution and tumor suppression efficiency of both the systems were studied in breast cancer xenograft models using BALB/c nude mice. Enhance accumulation of dox in the tumor tissue and significant tumor reduction were observed when treated with encapsulated dox using the HA based nanocarriers as opposed to free dox.