0000000000009423
AUTHOR
Camilla Pecoraro
1,2,4-Amino-triazine derivatives as pyruvate dehydrogenase kinase inhibitors: Synthesis and pharmacological evaluation
: Among the different hallmarks of cancer, deregulation of cellular metabolism turned out to be an essential mechanism in promoting cancer resistance and progression. The pyruvate dehydrogenase kinases (PDKs) are well known as key regulators in cells metabolic process and their activity was found to be overexpressed in different metabolic alerted types of cancer, including the high aggressive pancreatic ductal adenocarcinoma (PDAC). To date few PDK inhibitors have been reported, and the different molecules developed are characterized by structural chemical diversity. In an attempt to find novel classes of potential PDK inhibitors, the molecular hybridization approach, which combine two or m…
Thiazole Analogues of the Marine Alkaloid Nortopsentin as Inhibitors of Bacterial Biofilm Formation
Anti-virulence strategy is currently considered a promising approach to overcome the global threat of the antibiotic resistance. Among different bacterial virulence factors, the biofilm formation is recognized as one of the most relevant. Considering the high and growing percentage of multi-drug resistant infections that are biofilm-mediated, new therapeutic agents capable of counteracting the formation of biofilms are urgently required. In this scenario, a new series of 18 thiazole derivatives was efficiently synthesized and evaluated for its ability to inhibit biofilm formation against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 25923 and S. aureus ATCC 6538 a…
Multi or Single-Kinase Inhibitors to Counteract Drug Resistance in Cancer: What is New?
The concept of protein kinase inhibition starts from the groundbreaking research on the role of these proteins in the regulation of fundamental processes, including proliferation, cell cycle, apoptosis, metabolism, and inflammation. Kinase genetic mutations, as well as overexpression and dysregulation, can contribute to the development of several diseases, including neoplasms, leading to relapses and resistance to standard drug chemotherapy [1-3].
Novel strategies in the war against antibiotic resistance
The global threat of antibiotic resistance is steadily growing. Antibiotic resistancemay involve any class of antibiotic, including second- and third-line agents that have been considered to date the last-resort drugs to counteract common infections. We may lose our capability to keep under control many common bacterial infections [1]. Despite this, in the past decade significant research efforts have been made to develop new antibacterial strategies able to treat multidrug-resistant infections; however, no new therapeutic approach has yet reached the clinic [2,3]. In order to identify new valuable antimicrobial drugs, it is important to consider the main bacterial resistance mechanisms in …
Recent Developments in the Inhibition of Bacterial Adhesion as Promising Anti-Virulence Strategy
Infectious diseases caused by antimicrobial-resistant strains have become a serious threat to global health, with a high social and economic impact. Multi-resistant bacteria exhibit various mechanisms at both the cellular and microbial community levels. Among the different strategies proposed to fight antibiotic resistance, we reckon that the inhibition of bacterial adhesion to host surfaces represents one of the most valid approaches, since it hampers bacterial virulence without affecting cell viability. Many different structures and biomolecules involved in the adhesion of Gram-positive and Gram-negative pathogens can be considered valuable targets for the development of promising tools t…
Synthesis and Antioxidative Properties of 1,2,3,4-Tetrahydropyridine Derivatives with Different Substituents in 4-Position
Natural products are an excellent source of inspiration for the development of new drugs. Among them, betalains have been extensively studied for their antioxidant properties and potential application as natural food dyes. Herein, we describe the seven-step synthesis of new betalamic acid analogs without carboxy groups in the 2- and 6-position with an overall yield of ~70%. The Folin–Ciocalteu assay was used to determine the antioxidant properties of protected intermediate 21. Additionally, the five-step synthesis of betalamic acid analog 35 with three ester moieties was performed. Using NMR techniques, the stability of the obtained compounds towards oxygen was analyzed.
CHK1 inhibitor sensitizes resistant colorectal cancer stem cells to nortopsentin
Summary Limited therapeutic options are available for advanced colorectal cancer (CRC). Herein, we report that exposure to a neo-synthetic bis(indolyl)thiazole alkaloid analog, nortopsentin 234 (NORA234), leads to an initial reduction of proliferative and clonogenic potential of CRC sphere cells (CR-CSphCs), followed by an adaptive response selecting the CR-CSphC-resistant compartment. Cells spared by the treatment with NORA234 express high levels of CD44v6, associated with a constitutive activation of Wnt pathway. In CR-CSphC-based organoids, NORA234 causes a genotoxic stress paralleled by G2-M cell cycle arrest and activation of CHK1, driving the DNA damage repair of CR-CSphCs, regardless…
Cyclin dependent kinase-1 (Cdk-1) inhibition as a novel therapeutic strategy against pancreatic ductal adenocarcinoma (pdac)
Simple Summary Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers in humans, due to late diagnosis and limited treatment possibilities. Improved treatment for PDAC patients is warranted. Cyclin-dependent kinase 1 (CDK1) is a stimulator of cell cycle progression and its activity is regularly enhanced in pancreatic cancer cells. Therefore, CDK1 has been proposed as a novel drug target to treat patients with PDAC. This review describes the potential of CDK1 inhibition as a treatment for PDAC by outlining the molecular pathways influenced by CDK1 inhibition and new therapeutic strategies. Abstract The role of CDK1 in PDAC onset and development is two-fold. Firstly, since …
GSK3β as a novel promising target to overcome chemoresistance in pancreatic cancer
Pancreatic cancer is an aggressive malignancy with increasing incidence and poor prognosis due to its late diagnosis and intrinsic chemoresistance. Most pancreatic cancer patients present with locally advanced or metastatic disease characterized by inherent resistance to chemotherapy. These features pose a series of therapeutic challenges and new targets are urgently needed. Glycogen synthase kinase 3 beta (GSK3β) is a conserved serine/threonine kinase, which regulates key cellular processes including cell proliferation, DNA repair, cell cycle progression, signaling and metabolic pathways. GSK3β is implicated in non-malignant and malignant diseases including inflammation, neurodegenerative …
Synthesis and cytotoxic activity of 3-[2-(1H-indol-3-yl)-1,3-thiazol-4-yl]-1H-pyrrolo[3,2-c]pyridine hydrobromides, analogues of the marine alkaloid nortopsentin
A new series of thiazole nortopsentin analogues with a 5-azaindole moiety was conveniently synthesized in good to excellent yields by an Hantzsch reaction between thioamides and α-bromoacetyl compounds. The cytotoxic activity of the new derivatives was tested against different human tumor cell lines of the NCI full panel. All tested compounds were active against all of the investigated cell lines showing GI50 values from micro to submicromolar levels. Some of the new analogues exhibited good selectivities against different NCI sub-panels.
Development of a new indole derivative dry powder for inhalation for the treatment of biofilm-associated lung infections
The aim of this work was to produce an inhalable dry powder formulation of a new anti-biofilm compound (SC38). For this purpose, chitosan was used as a polymeric carrier and l-leucine as a dispersibility enhancer. SC38 was entrapped by spray-drying into previously optimized chitosan microparticles. The final formulation was fully characterized in vitro in terms of particle morphology, particle size and distribution, flowability, aerodynamic properties, anti-biofilm activity and effects on lung cell viability. The SC38-loaded chitosan microparticles exhibited favorable aerodynamic properties with emitted and respirable fractions higher than 80 % and 45 % respectively. The optimized formulati…
SYNTHESIS AND BIOLOGICAL EVALUATION OF NOVEL SMALL MOLECULES AS PROMISING ALTERNATIVE AGENTS TO COUNTERACT DRUG RESISTANCE IN CANCER AND MICROBIAL INFECTIONS
Il cancro rimane un grave problema di salute pubblica, rappresentando la seconda principale causa di morte in tutto il mondo. Tra le diverse tipologie di tumori, l'adenocarcinoma duttale pancreatico (PDAC) è una delle forme più letali nell'uomo, a causa della diagnosi tardiva e delle limitate possibilità di trattamento. Pertanto, lo studio di nuove strategie terapeutiche per i pazienti affetti da PDAC è altamente necessario. Allo stesso modo, il mesotelioma rappresenta una malattia rara ma aggressiva, difficile da diagnosticare per il lungo periodo di latenza prima dei segni clinici. Gli approcci terapeutici standard includono la chirurgia, la chemioterapia e la radioterapia. Tuttavia, la s…
1,2,4-Oxadiazole topsentin analogs as staphylococcal biofilm inhibitors targeting the bacterial transpeptidase sortase A
The inhibition or prevention of biofilm formation represents an emerging strategy in the war against antibiotic resistance, interfering with key players in bacterial virulence. This approach includes the inhibition of the catalytic activity of transpeptidase sortase A (Srt A), a membrane enzyme responsible for covalently attaching a wide variety of adhesive matrix molecules to the peptidoglycan cell wall in Gram-positive strains. A new series of seventeen 1,2,4-oxadiazole derivatives was efficiently synthesized and screened as potential new anti-virulence agents. The ability of inhibiting biofilm formation was evaluated against both Gram-positive and Gram-negative pathogens. Remarkably, all…
Hop-derived fraction rich in beta acids and prenylflavonoids regulates the inflammatory response in dendritic cells differently from quercetin: unveiling metabolic changes by mass spectrometry-based metabolomics.
Dendritic cells (DCs) represent a heterogeneous family of immune cells that link innate and adaptive immunity and their activation is linked to metabolic changes that are essential to support their activity and function. Hence, targeting the metabolism of DCs represents an opportunity to modify the inflammatory and immune response. Among the natural matrices, Humulus lupulus (Hop) compounds have recently been shown to exhibit immunomodulatory and anti-inflammatory activity. This study aimed to evaluate the ability of specific Hop fractions to modulate DCs metabolism after stimulation with lipopolysaccharide (LPS) by an untargeted metabolomics approach and compare their effect with flavonol …
A New Oxadiazole-Based Topsentin Derivative Modulates Cyclin-Dependent Kinase 1 Expression and Exerts Cytotoxic Effects on Pancreatic Cancer Cells
Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal form of cancer characterized by drug resistance, urging new therapeutic strategies. In recent years, protein kinases have emerged as promising pharmacological targets for the treatment of several solid and hematological tumors. Interestingly, cyclin-dependent kinase 1 (CDK1) is overexpressed in PDAC tissues and has been correlated to the aggressive nature of these tumors because of its key role in cell cycle progression and resistance to the induction of apoptosis. For these reasons, CDK1 is one of the main causes of chemoresistance, representing a promising pharmacological target. In this study, we report the synthesis of new 1,2,4…
SF3B1 modulators affect key genes in metastasis and drug influx: a new approach to fight pancreatic cancer chemoresistance.
Aim: Because mutations of splicing factor 3B subunit-1 (SF3B1) have been identified in 4% of pancreatic ductal adenocarcinoma (PDAC) patients, we investigated the activity of new potential inhibitors of SF3B1 in combination with gemcitabine, one of the standard drugs, in PDAC cell lines. Methods: One imidazo[2,1-b][1,3,4]thiadiazole derivative (IS1) and three indole derivatives (IS2, IS3 and IS4), selected by virtual screening from an in-house library, were evaluated by the sulforhodamine-B and wound healing assay for their cytotoxic and antimigratory activity in the PDAC cells SUIT-2, Hs766t and Panc05.04, the latter harbouring the SF3B1 mutations. The effects on the splicing pattern of pr…
Therapeutic Strategies To Counteract Antibiotic Resistance in MRSA Biofilm‐Associated Infections
Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as one of the leading causes of persistent human infections. This pathogen is widespread and is able to colonize asymptomatically about a third of the population, causing moderate to severe infections. It is currently considered the most common cause of nosocomial infections and one of the main causes of death in hospitalized patients. Due to its high morbidity and mortality rate and its ability to resist most antibiotics on the market, it has been termed a “superbug”. Its ability to form biofilms on biotic and abiotic surfaces seems to be the primarily means of MRSA antibiotic resistance and pervasiveness. Importantly, more tha…
Metabolomics-assisted discovery of a new anticancer GLS-1 inhibitor chemotype from a nortopsentin-inspired library: From phenotype screening to target identification
The enzyme glutaminase-1 (GLS-1) has shown a clear and coherent implication in the progression and exacerbation of different aggressive tumors such as glioblastoma, hepatocarcinoma, pancreas, bone, and triple-negative breast cancer. Few chemotypes are currently available as selective GLS-1 inhibitors, and still, fewer of them are at the clinical stage. In the present paper, starting from a naturally-inspired antitumor compound library, metabolomics has been used to putatively identify the molecular mechanism underlying biological activity. GLS-1 was identified as a potential target. Biochemical analysis confirmed the hypothesis leading to the identification of a new hit compound acting as a…
New Imidazo[2,1-b][1,3,4]Thiadiazole Derivatives Inhibit FAK Phosphorylation and Potentiate the Antiproliferative Effects of Gemcitabine Through Modulation of the Human Equilibrative Nucleoside Transporter-1 in Peritoneal Mesothelioma
Background/aim A new class of imidazo[2,1-b][1,3,4]thiadiazole compounds have recently been evaluated as inhibitors of phosphorylation of focal adhesion kinase (FAK) in pancreatic cancer. FAK is overexpressed in mesothelioma and has recently emerged as an interesting target for the treatment of this disease. Materials and methods Ten imidazo[2,1-b][1,3,4]thiadiazole compounds characterized by indole bicycle and a thiophene ring, were evaluated for their cytotoxic activity in two primary cell cultures of peritoneal mesothelioma, MesoII and STO cells. Results Compounds 1a and 1b showed promising antitumor activity with IC50 values in the range of 0.59 to 2.81 μM in both cell lines growing as …
1,2,4-Oxadiazole Topsentin Analogs with Antiproliferative Activity against Pancreatic Cancer Cells, Targeting GSK3β Kinase.
A new series of topsentin analogs, in which the central imidazole ring of the natural lead was replaced by a 1,2,4- oxadiazole moiety, was efficiently synthesized. All derivatives were pre-screened for antiproliferative activity against the National Cancer Institute (NCI-60) cell lines panel. The five most potent compounds were further investigated in various pancreatic ductal adenocarcinoma (PDAC) cell lines, including SUIT-2, Capan-1, and Panc-1 cells, eliciting EC50 values in the micromolar and sub-micromolar range, associated with significant reduction of cell migration. These remarkable results might be explained by the effects of these new topsentin analogues on epithelial-to-mesenchy…
Eight-membered heterocycles with two heteroatoms in a 1,3-relationship of interest in medicinal chemistry
This chapter deals with 1,3-diheterocines, eight-membered heterocyclic systems with two heteroatoms, N, O and S, in a 1,3 relationship, exhibiting biological properties and exhaustively covers the literature from 2007 to the end of November 2019. The biological results of 1,3-diazocines, 1,3-oxazocines, 1,3-dioxocins and 1,3-thiazocines, that are the largest class of 1,3-diheterocines, were collected together with the few results available for 1,3-oxathiocin and 1,3-dithiocin derivatives at that time.
Discovery of the 3-Amino-1,2,4-triazine-Based Library as Selective PDK1 Inhibitors with Therapeutic Potential in Highly Aggressive Pancreatic Ductal Adenocarcinoma
Pyruvate dehydrogenase kinases (PDKs) are serine/threonine kinases, that are directly involved in altered cancer cell metabolism, resulting in cancer aggressiveness and resistance. Dichloroacetic acid (DCA) is the first PDK inhibitor that has entered phase II clinical; however, several side effects associated with weak anticancer activity and excessive drug dose (100 mg/kg) have led to its limitation in clinical application. Building upon a molecular hybridization approach, a small library of 3-amino-1,2,4-triazine derivatives has been designed, synthesized, and characterized for their PDK inhibitory activity using in silico, in vitro, and in vivo assays. Biochemical screenings showed that …
Structural Manipulations of Marine Natural Products Inspire a New Library of 3-Amino-1,2,4-Triazine PDK Inhibitors Endowed with Antitumor Activity in Pancreatic Ductal Adenocarcinoma
Pancreatic ductal adenocarcinoma (PDAC) is one of the main aggressive types of cancer, characterized by late prognosis and drug resistance. Among the main factors sustaining PDAC progression, the alteration of cell metabolism has emerged to have a key role in PDAC cell proliferation, invasion, and resistance to standard chemotherapeutic agents. Taking into account all these factors and the urgency in evaluating novel options to treat PDAC, in the present work we reported the synthesis of a new series of indolyl-7-azaindolyl triazine compounds inspired by marine bis-indolyl alkaloids. We first assessed the ability of the new triazine compounds to inhibit the enzymatic activity of pyruvate de…