RESUMEN
Anti-angiogenesis targeting vascular endothelial growth factor receptor 2 (VEGFR2) has emerged as a vital tool for cancer treatment. In this study, a new series of biphenylurea/thiourea derivatives tagged with heteroarylsulfonamide motifs (3a-l) was designed and synthesized as novel VEGFR2 inhibitors. The biochemical profiles of the target compounds were investigated using viability of human umbilical vascular endothelial cells (HUVECs), migration assay and Western blot using sorafenib as reference antiangiogenic drug. Most of the tested compounds exhibited significant antiproliferative activity against HUVECs, where compounds 3a, 3e, 3g, 3h and 3l exhibited better antiproliferative activity than sorafenib. All compounds significantly inhibited VEGF stimulated migration of HUVECs at 10 µM dose with (3a, 3e, 3g, 3h and 3l) showing better or comparable inhibitory activities to that of sorafenib. Moreover, Western blotting analysis confirmed antiangiogenic effect of those compounds with significant reduction in the level of VEGFR-2 compared to sorafenib. Finally, cytotoxicity screening of these derivatives against four cancer cells and RPE1 as normal cell line was performed. The mechanistic effectiveness in cell cycle progression and apoptotic induction were evaluated for the promising compound 3e due to its remarkable cytotoxic activity against tested cancer cell lines and significant VEGFR-2 inhibition. Flow cytometric analysis showed that compound 3e induced cell growth arrest at G2/M phase and stimulated the apoptotic death of HepG2 cells.
Asunto(s)
Inhibidores de la Angiogénesis/síntesis química , Diseño de Fármacos , Inhibidores de Proteínas Quinasas/síntesis química , Sulfonamidas/química , Tiourea/análogos & derivados , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Inhibidores de la Angiogénesis/metabolismo , Inhibidores de la Angiogénesis/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Sorafenib/farmacología , Relación Estructura-Actividad , Tiourea/metabolismo , Tiourea/farmacología , Factor A de Crecimiento Endotelial Vascular/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Series of piperidone-salicylate conjugates were synthesized through the reaction of 3E,5E-bis(arylidene)-4-piperidones with the appropriate acid chloride of acetylsalicylate in the presence of triethylamine. All the synthesized conjugates reveal antiproliferative properties against A431 (squamous skin) cancer cell line with potency higher than that of 5-fluorouracil. Many of the synthesized agents also exhibit promising antiproliferative properties against HCT116 (colon) cancer cell line, of which 5o and 5c are the most effective with 12.9, 9.8 folds potency compared with Sunitinib. Promising activity is also shown against MCF7 (breast) cancer cell line with 1.19, 1.12 folds relative to 5-fluorouracil. PI-flow cytometry of compound 5c supports the arrest of cell cycle at G1-phase. However, compound 5o and Sunitinib arrest the cell cycle at S-phase. The synthesized conjugates can be considered as multi-targeted tyrosine kinase inhibitors due to the promising properties against VEGFR-2 and EGFR in MCF7 and HCT116. CDOCKER studies support the EGFR inhibitory properties. Compounds 5p and 5i possessing thienylidene heterocycle are anti-SARS-CoV-2 with high therapeutic indices. Many of the synthesized agents show enhanced COX-1/2 properties than aspirin with better selectivity index towards COX-2 relative to COX-1. The possible applicability of the potent candidates discovered as antitumor and anti-SARS-CoV-2 is supported by the safe profile against normal (non-cancer, RPE1 and VERO-E6) cells.
Asunto(s)
Antineoplásicos/química , Antivirales/química , Aspirina/química , Curcumina/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Antivirales/metabolismo , Antivirales/farmacología , COVID-19/patología , COVID-19/virología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclooxigenasa 1/química , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/química , Ciclooxigenasa 2/metabolismo , Diseño de Fármacos , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Humanos , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Unión Proteica , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/aislamiento & purificación , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Sets of 3-alkenyl-2-oxindoles (6,10,13) were synthesized in a facile synthetic pathway through acid dehydration (EtOH/HCl) of the corresponding 3-hydroxy-2-oxoindolines (5,9,12). Single crystal (10a,c) and powder (12a,26f) X-ray studies supported the structures. Compounds 6c and 10b are the most effective agents synthesized (about 3.4, 3.3 folds, respectively) against PaCa2 (pancreatic) cancer cell line relative to the standard reference used (Sunitinib). Additionally, compound 10b reveals antiproliferative properties against MCF7 (breast) cancer cell with IC50 close to that of Sunitinib. CAM testing reveals that compounds 6 and 10 demonstrated qualitative and quantitative decreases in blood vessel count and diameter with efficacy comparable to that of Sunitinib, supporting their anti-angiogenic properties. Kinase inhibitory properties support their multi-targeted inhibitory activities against VEGFR-2 and c-kit in similar behavior to that of Sunitinib. Cell cycle analysis studies utilizing MCF7 exhibit that compound 6b arrests the cell cycle at G1/S phase while, 10b reveals accumulation of the tested cell at S phase. Compounds 6a and 10b reveal potent antiviral properties against SARS-CoV-2 with high selectivity index relative to the standards (hydroxychloroquine, chloroquine). Safe profile of the potent synthesized agents, against normal cells (VERO-E6, RPE1), support the possible development of better hits based on the attained observations.
Asunto(s)
Antineoplásicos/farmacología , Antivirales/síntesis química , Oxindoles/síntesis química , SARS-CoV-2/efectos de los fármacos , Animales , Antivirales/farmacología , Ciclo Celular , Línea Celular Tumoral , Embrión de Pollo , Chlorocebus aethiops , Humanos , Oxindoles/farmacología , Células Vero , Tratamiento Farmacológico de COVID-19RESUMEN
New functionalized acrylamide derivatives bearing sulfisoxazole moiety were designed to target bacterial dihydropteroate synthase (DHPS). The in vitro antimicrobial activities of these compounds were assessed. The E-configuration of compound 5b was proved by single crystal X-ray analysis. Compounds 5g and 5h displayed double the activity of ampicillin against B. subtilis. Also, 5h was two times more active than gentamycin against E. coli. Interestingly, compounds 5f-g, 7c, 8a, 8c exhibited two folds the potency of amphotericin B against S. racemosum while 5h displayed three folds the activity of amphotericin B against S. racemosum. Most of the synthesized compounds showed superior activities to the parent sulfisoxazole and were non-toxic to normal cells. DHPS is confirmed to be a putative target for our compounds via antagonizing their antibacterial activity by the folate precursor (p-aminobenzoic acid) and product (methionine) on E. coli ATCC 25922. Docking experiments against DHPS rationalized the observed antibacterial activity. Additionally, compound 5g was evaluated as a selective targeting vector for 99mTc that showed a remarkable uptake and targeting ability towards the infection site that was induced in mice.
Asunto(s)
Acrilamida/farmacología , Antibacterianos/farmacología , Dihidropteroato Sintasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Sulfisoxazol/farmacología , Acrilamida/química , Antibacterianos/síntesis química , Antibacterianos/química , Células Cultivadas , Dihidropteroato Sintasa/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/crecimiento & desarrollo , Humanos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Sulfisoxazol/químicaRESUMEN
A series of N-substituted (Z)-2-imino-(5Z)-ylidene thiazolidines/thiazolidin-4-ones were synthesized and their antiproliferative activities against colon (HCT-116) and breast (MCF7) cancer cell lines were evaluated utilizing an MTT growth assay. A 2D-QSAR investigation was conducted to probe and validate the obtained antiproliferative properties for the thiazolidine derivatives. The majority of the thiazolidines exhibit higher potency against a colon cancer cell line relative to the standard reference. The p-halophenylimino p-anisylidene derivatives exhibited the highest anti-proliferative activity against HCT116 relative to control (IC50â¯=â¯8.9-10.0⯵M compared to 20.4⯵M observed for 5-fluorouracil as positive control). An X-ray study confirmed the Z, Z'-configurations for two examples of the synthesized compounds.
Asunto(s)
Antineoplásicos/farmacología , Relación Estructura-Actividad Cuantitativa , Tiazolidinas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Humanos , Células MCF-7 , Modelos Moleculares , Estructura Molecular , Tiazolidinas/síntesis química , Tiazolidinas/químicaRESUMEN
Marine organisms have been considered as the richest sources of novel bioactive metabolites, which can be used for pharmaceutical purposes. In the last years, the interest for marine microorganisms has grown for their enormous biodiversity and for the evidence that many novel compounds isolated from marine invertebrates are really synthesized by their associated bacteria. Nevertheless, the discovery of a chemical communication Quorum sensing (QS) between bacterial cells and between bacteria and host has gained the researchers to expand the aim of their study toward the role of bacteria associated with marine invertebrates, such as marine sponge. In the present paper, we report the evaluation of biological activities of different extracts of bacteria Vibrio sp. and Bacillus sp. associated with marine sponges Dysidea avara and Ircinia variabilis, respectively. Moreover, we evaluated the biological activities of some diketopiperazines (DKPs), previously isolated, and able to activate QS mechanism. The results showed that all extracts, fractions, and DKPs showed low scavenging activity against DPPH and superoxide anion, low cytotoxic and anti-tyrosinase activities, but no antimicrobial and acetylcholinesterase inhibitory activities. One DKP [cyclo-(trans-4-hydroxy-L-prolyl-L-leucine)] has the highest α-glucosidase inhibitory activity even than the standard acarbose.
Asunto(s)
Bacterias/química , Dicetopiperazinas/farmacología , Poríferos/microbiología , Animales , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodiversidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dicetopiperazinas/análisis , Dicetopiperazinas/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Glucosidasas/análisis , Glucosidasas/antagonistas & inhibidores , HumanosRESUMEN
Cancer is a leading cause of death in several countries. In the search for new anticancer drugs, marine organisms have played an important role in the discovery of lead compounds and the development of new pharmaceuticals for their wide diversity of chemical structures and biological activities. In the present study, the cytotoxicity on colorectal cancer cells HCT116 exerted by marine fungus Aspergillus sp. 2C1-EGY extracts associated with the soft coral Sinularia sp. was investigated; the sub-fractions Fr 2c and Fr 2d had significantly high cytotoxic activity (88 and 85%, respectively). Moreover, the major hexadecanoic, octadecanoic, and octadecenoic acids as well as their methyl esters were isolated. GC/MS analysis revealed the identification of 46 major and minor compounds, from which 19 saturated and unsaturated fatty acids and eight fatty acid esters were identified.
Asunto(s)
Antozoos/microbiología , Antineoplásicos/farmacología , Aspergillus/química , Productos Biológicos/farmacología , Animales , Antineoplásicos/química , Aspergillus/clasificación , Aspergillus/genética , Productos Biológicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Espectroscopía de Resonancia Magnética , Filogenia , ARN Ribosómico 18S/genéticaRESUMEN
Cancer remains a formidable global health challenge, with current treatment modalities such as chemotherapy, radiotherapy, surgery, and targeted therapy often hindered by low efficacy and adverse side effects. The indole scaffold, a prominent heterocyclic structure, has emerged as a promising candidate in the fight against cancer. This review consolidates recent advancements in developing natural and synthetic indolyl analogs, highlighting their antiproliferative activities against various cancer types over the past five years. These analogs are categorized based on their efficacy against common cancer types, supported by biochemical assays demonstrating their antiproliferative properties. In this review, emphasis is placed on elucidating the mechanisms of action of these compounds. Given the limitations of conventional cancer therapies, developing targeted therapeutics with enhanced selectivity and reduced side effects remains a critical focus in oncological research.
RESUMEN
CONTEXT: This study is a continuation of our previous work in which a bioassay screening of 346 methanol extracts from 281 Egyptian plant species was carried out for in vitro schistosomicidal activity. OBJECTIVE: Another 309 methanol extracts from 278 plant species were subjected to the bioassay screening using the same technique on viable Schistosoma mansoni Sambon (Schistosomatidae) mature worms in specialized culture medium (Roswell Park Memorial Institute medium 1640) in a trial to discover a source for a schistosomiasis drug from Egyptian flora. MATERIAL AND METHODS: The methanol plant extracts were tested in vitro against viable S. mansoni mature worms in culture medium. Viability of worms was examined after exposure to 100 µg/ml of the extract in the medium for 24 h. Negative (dimethyl sulfoxide) and positive (praziquantel) controls were simultaneously used. Extracts showing schistosomicidal activity were further subjected to determination of their (Lethal concentration) LC50 and LC90 values. RESULTS: Confirmed in vitro antischistosomal activity was found in 42 extracts. Of these, 14 plant species possessed considerably high antischistosomal activity (LC50 ≤ 15 µg/ml), viz. Callistemon viminalis (Soland. Ex Gaertn) Cheel, C. rigidus R.Br., C. speciosus (Sims.) DC, C. citrinus Stapf, Eucalyptus citriodora Hook, E. rostrata Dehnh., Eugenia edulis Vell, E. javanica Lam syn. Syzygium samarangense (Blume) Merril, Melaleuca leucadendron (L.) L., M. stypheloides Sm. (all belong to Myrtaceae), Cryptostegia grandiflora R.Br. (Asclepiadaceae), Zilla spinosa (L.) Prantl (Cruciferae), Ficus trijuja L. (Moraceae) and Fagonia mollis Delile (Zygophylacae). DISCUSSION AND CONCLUSION: These species may represent additional natural sources of bioactive material that deserve further investigation for drug discovery against schistosomiasis.
Asunto(s)
Descubrimiento de Drogas , Extractos Vegetales/farmacología , Plantas/química , Schistosoma mansoni/efectos de los fármacos , Esquistosomicidas/farmacología , Animales , Egipto , Femenino , Concentración 50 Inhibidora , Masculino , Metanol/química , Myrtaceae/química , Componentes Aéreos de las Plantas/química , Extractos Vegetales/aislamiento & purificación , Schistosoma mansoni/crecimiento & desarrollo , Esquistosomicidas/aislamiento & purificación , Solventes/químicaRESUMEN
The goal of this work was to design nude bilosomes (Bil) and D-alpha-tocopheryl polyethylene glycol succinate (TPGS) surface coated bilosomes as an oral delivery platform for improving the antitumor activity and poor oral permeability of Curcumin (CUR). Twelve different formulae were acquired from 31.22 factorial analysis considering different independent variables: bile salt type; Sodium taurocholate (STC) or Sodium cholate (SC) and weight percent; 1% or 5 % W/W, both at 2 levels respectively, while Span 60:Cholesterol ratio at 3 levels (1:1, 5:1, 9:1). Following optimization, the selected optimum formula was picked up based on the favorable minimum particle size (187.2 ± 2.2 nm), maximum zeta potential value (-41.3 ± 2.2 mV) and maximum entrapment efficiency (93.4 ± 5.1%) which was further coated with TPGS. The mean fluorescence intensity (MFI) of CUR permeated from the optimum TPGS-F7 and CUR-Bil (F7) formulae exhibited 6.6 and 3.4 folds increase respectively adopting ex-vivo duodenal permeation assay relative to that of CUR suspension. Moreover, the cellular uptake efficiency via the established Caco-2 cells revealed that the uptake of CUR was 61.9 ± 5.3% and 34.76 ± 0.61% from TPGS-F7 and CUR-Bil (F7) relative to the uptake efficiency of CUR suspension (7.4 ± 2.12%). Coherently, TPGS-CUR-Bil showed excellent response expressed in dominant reduction in IC50 value (2.8 ± 0.07 µg/ml) against multidrug resistant (MDR) tumors following 48 h incubation of Doxorubicin Resistant Breast Cancer (MCF-7/ADR) cell lines.
Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Curcumina , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Células CACO-2 , Curcumina/farmacología , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Femenino , Humanos , Células MCF-7 , Tamaño de la Partícula , Polietilenglicoles/uso terapéutico , Vitamina E , alfa-TocoferolRESUMEN
Three sets of isatin-based Schiff bases were synthesized utilizing the molecular hybridization approach. Some of the synthesized Schiff bases show significant to moderate antiproliferative properties against MCF7 (breast), HCT116 (colon), and PaCa2 (pancreatic) cancer cell lines with potency compared to reference drugs 5-fluorouracil (5-FU) and Sunitinib. Among all, compound 17 f (3-((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)imino)-1-((1-(2-methoxyphenyl)-1H-1,2,3-triazol-4-yl)methyl)-5-methylindolin-2-one) exhibits promising antiproliferative properties against the MCF7 cancer cell line with 2.1-fold more potency than Sunitinib. However, among all the synthesized compounds, three (5-methylisatin derivatives) were the most effective against HCT116 in comparison to 5-FU. Compound 17 f exhibited the highest anti-angiogenic effect on the vasculature as it significantly reduced BV from 43â mm to 2â mm in comparison to 5.7â mm for Sunitinib and flow cytometry supports the arrest of the cell cycle at G1/S phases. In addition, compound 17 f also showed high VEGFR-2 inhibition properties against breast cancer cell lines. Robust 2D-QSAR studies supported the biological data.
Asunto(s)
Antineoplásicos , Isatina , Fluorouracilo/farmacología , Humanos , Relación Estructura-Actividad Cuantitativa , Bases de Schiff/farmacología , Sunitinib , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
A series of 1â³-(alkylsulfonyl)-dispiro[indoline-3,2'-pyrrolidine-3',3â³-piperidine]-2,4â³-diones 6aâo has been synthesized through regioselective multi-component azomethine dipolar cycloaddition reaction of 1-(alkylsulfonyl)-3,5-bis(ylidene)-piperidin-4-ones 3aâh. X-ray diffraction studies (6bâd,h) confirmed the structures. The majority of the synthesized analogs reveal promising antiproliferation properties against a variety of human cancer cell lines (MCF7, HCT116, A431 and PaCa2) with good selectivity index towards normal cell (RPE1). Some of the synthesized agents exhibit potent inhibitory properties against the tested cell lines with higher efficacies than the standard references (sunitinib and 5-fluorouracil). Compound 6m is the most potent. Multi-targeted inhibitory properties against EGFR and VEGFR-2 have been observed for the synthesized agents. Flow cytometry supports the antiproliferation properties and shows the tested agents as apoptosis and necrosis forming. Vero cell viral infection model demonstrates the anti-SARS-CoV-2 properties of the synthesized agents. Compound 6f is the most promising (about 3.3 and 4.8 times the potency of the standard references, chloroquine and hydroxychloroquine). QSAR models explain and support the observed biological properties.
Asunto(s)
Antineoplásicos , Tratamiento Farmacológico de COVID-19 , Compuestos de Espiro , Antineoplásicos/química , Línea Celular Tumoral , Humanos , Indoles , Estructura Molecular , SARS-CoV-2 , Compuestos de Espiro/química , Compuestos de Espiro/farmacologíaRESUMEN
A high-throughput screen of the cytotoxic activity of 2000 molecules from a commercial library in three human colon cancer cell lines and two normal cell types identified the acridine acriflavin to be a colorectal cancer (CRC) active drug. Acriflavine was active in cell spheroids, indicating good drug penetration and activity against hypoxic cells. In a validation step based on primary cultures of patient tumor cells, acriflavine was found to be more active against CRC than ovarian cancer and chronic lymphocytic leukemia. This contrasted to the activity pattern of the CRC active standard drugs 5-fluorouracil, irinotecan and oxaliplatin. Mechanistic studies indicated acriflavine to be a dual topoisomerase I and II inhibitor. In conclusion, the strategy used seems promising for identification of new diagnosis-specific cancer drugs.
Asunto(s)
Acriflavina/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Inhibidores de Topoisomerasa I/farmacología , Inhibidores de Topoisomerasa II/farmacología , Camptotecina/análogos & derivados , Camptotecina/farmacología , Línea Celular Tumoral/efectos de los fármacos , ADN-Topoisomerasas de Tipo I/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Fluorouracilo/farmacología , Ensayos Analíticos de Alto Rendimiento , Humanos , Irinotecán , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Masculino , Compuestos Organoplatinos/farmacología , Neoplasias Ováricas/tratamiento farmacológico , OxaliplatinoRESUMEN
BACKGROUND: Bacterial infections are considered as one of the major global health threats, so it is very essential to design and develop new antibacterial agents to overcome the drawbacks of existing antibacterial agents. METHODS: The aim of this work is to synthesize a series of new fluoroquinolone-3-carboxamide amino acid conjugates by molecular hybridization. We utilized benzotriazole chemistry to synthesize the desired hybrid conjugates. RESULTS: All the conjugates were synthesized in good yields, characterized, evaluated for their antibacterial activity. The compounds were screened for their antibacterial activity using methods adapted from the Clinical and Laboratory Standards Institute. Synthesized conjugates were tested for activity against medically relevant pathogens; Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27856) Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 19433). CONCLUSION: The observed antibacterial experimental data indicates the selectivity of our synthesized conjugates against E.Coli. The protecting group on amino acids decreases the antibacterial activity. The synthesized conjugates are non-toxic to the normal cell lines. The experimental data were supported by computational studies.
Asunto(s)
Aminoácidos/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Fluoroquinolonas/síntesis química , Fluoroquinolonas/farmacología , Modelos Moleculares , Antibacterianos/química , Línea Celular , Técnicas de Química Sintética , Fluoroquinolonas/química , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Relación Estructura-ActividadRESUMEN
Most of the currently used cancer therapeutics are natural products. These agents were generally discovered based on their toxicity to tumour cells using various bioassays. Although the exact mechanisms of action of the most commonly used cancer therapeutics such as anthracyclins, podophyllotoxins and camptothecin are incompletely understood, it is becoming increasingly clear that these agents often show complex modes of action at the cellular level, interacting with numerous targets. Such complex modes of action may be the very reason for clinical efficacy. For discovering new cytotoxic anticancer drugs sophisticated screening methods were used. The principles of such screening projects conducted, using collections of purified natural products or extracts from plants have been described. By performing simple but robust prescreening tests such as the brine shrimp assay, bioactive extracts can be identified. Extracts (65) prepared from a collection of Egyptian plants were identified that showed cytotoxity on HepG2 cells. Interestingly, 22 (33%) of these raw extracts, induced > 2-fold induction of caspase-cleavage activity in a colon carcinoma cell line, consistent with induction of apoptosis. Only a fraction of the diversity of the biosphere has been tested for biological activity and novel cancer therapeutics remains to be discovered.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Extractos Vegetales/farmacología , Antineoplásicos/química , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Activación Enzimática/efectos de los fármacos , Células HCT116 , Células Hep G2 , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología , Extractos Vegetales/química , Especificidad de la EspecieRESUMEN
Photodynamic therapy (PDT) is a non-invasive treatment strategy that includes the combination of three components-a photosensitizer, a light source, and tissue oxygen. PDT can be used for the treatment of skin diseases such as squamous cell carcinoma. The photosensitizer used in this study is the naturally derived chlorophyll derivative chlorin e6 (Ce6), which was encapsulated in ultradeformable ethosomes. Singlet oxygen production by Ce6 upon laser light irradiation was not significantly affected by encapsulation into ethosomes. PDT of squamous cell carcinoma cells treated with Ce6 ethosomes triggered increased mitochondrial superoxide levels and increased caspase 3/7 activity, resulting in concentration- and light-dose-dependent cytotoxicity. Ce6 ethosomes showed good penetration into 3D squamous cell carcinoma spheroids, which upon laser light irradiation exhibited reduced size, proliferation, and viability. The PDT effect of Ce6 ethosomes was specific and showed higher cytotoxicity against squamous cell carcinoma spheroids compared to normal skin fibroblast spheroids. In addition, PDT treatment of squamous cell carcinoma xenografts grown on chorioallantoic membranes of chick eggs (CAM) exhibited reduced expression of Ki-67 proliferation marker and increased terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining, indicating reduced proliferation and activation of apoptosis, respectively. The results demonstrate that Ce6-loaded ethosomes represent a convenient formulation for photodynamic treatment of squamous cell carcinoma.
RESUMEN
A set of dispiro[indoline-3,2'-pyrrolidine-3',3''-pyrrolidines] 8a-l was regioselectively synthesized utilizing multi-component azomethine cycloaddition reaction of 3-(arylmethylidene)pyrrolidine-2,5-diones 5a-e, isatins 6a-c and sarcosine 7. Single crystal X-ray studies of 8c add conclusive support for the structure. Compounds 8e and 8g reveal cholinesterase inhibitory properties with promising efficacy against both AChE and BChE and were found to be more selective towards AChE than BChE as indicted by the selectivity index like Donepezil (a clinically used cholinesterase inhibitory drug). Molecular modeling studies assist in understanding the bio-observations and identifying the responsible parameters behind biological properties.
RESUMEN
A series of new fluoroquinolone conjugates 8a-g and 9a-f were synthesized via benzotriazole-mediated synthetic approach with good yield and purity. Some of the synthesized analogs exhibited significant antibacterial properties against Escherichia coli and Staphylococcus aureus with potency higher than that of the parent drugs through in vitro standard bioassay procedure (conjugates 8c and 8d reveal antimicrobial properties with potency 1.9, 61.9, 20.7 and 2.4, 37.1, 8.3 folds relative to the parent antibiotic 6 against E. coli, S. aureus, and Enterococcus faecalis, respectively). The observed experimental data were supported by enzymatic DNA gyrase inhibitory property. Developed BMLR-QSAR model validates the observed experimental data and recognizes the parameters responsible for the enhanced antibacterial properties.
Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Ácido Dicloroacético/farmacología , Fluoroquinolonas/farmacología , Inhibidores de Topoisomerasa II/farmacología , Antibacterianos/síntesis química , Ácido Dicloroacético/química , Escherichia coli/efectos de los fármacos , Fluoroquinolonas/química , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Inhibidores de Topoisomerasa II/síntesis química , Inhibidores de Topoisomerasa II/químicaRESUMEN
Cisplatin is a clinically important chemotherapeutical agent used to treat epithelial malignancies. High concentrations (20-100 microM) of cisplatin have been used in numerous studies to induce apoptosis of carcinoma cells grown in monolayer culture over 24-48 hr. These conditions may not be relevant to 3-D tumor tissue in vivo and the importance of apoptosis for tumor response is controversial. We here studied the effects of cisplatin on a 3-D colon carcinoma in vitro model (multicellular spheroids). Cisplatin at a dose of 40 microM induced active caspase-3 preferentially in the peripheral 30 microm cell layer of spheroids, mainly during late stages (72-96 hr). The p53 response to cisplatin was also largely confined to peripheral cell layers. Despite the use of a high cisplatin concentration, a significant fraction of the cells in the spheroids survived treatment. A high proportion of surviving cells stained positive for beta-galactosidase, a marker of premature senescence. Cells growth-arrested by cisplatin treatment showed a higher spontaneous cell death rate than untreated proliferating cells. We propose that acute apoptosis is of minor significance for the overall response of carcinoma cells to cisplatin treatment.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Técnicas de Cultivo de Célula , Cisplatino/farmacología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Animales , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Humanos , Técnicas para Inmunoenzimas , Ratones , Ratones SCID , Esferoides Celulares , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Photodynamic therapy (PDT) is a localized treatment strategy used for skin cancers such as squamous cell carcinoma (SCC), the second most common form of skin cancer. PDT combines a photosensitizer, laser source and tissue oxygen. In this study, the selected photosensitizer, ferrous chlorophyllin (Fe-CHL) was loaded in ethosomes and lipid coated chitosan (PC/CHI) nanocarriers to enhance skin delivery of Fe-CHL for potential PDT of squamous carcinoma. The nanocarrier formulations were characterized and studied for their skin retention and penetration depth of Fe-CHL across mouse skin ex vivo using high performance liquid chromatography and confocal microscopy. Confocal microscope images of mouse skin showed deeper penetration of ethosomes down to the dermis when compared to PC/CHI that was confined to the epidermis, although they showed no significant difference in skin retention. Immunohistochemistry (IHC) staining with ki67 and TUNEL show maintained skin structure and no cytotoxic effects of the nanocarrier gel formulations before laser exposure to mouse skin. The nanocarriers were also studied for their PDT effect against human SCC monolayer and three-dimensional (3-D) spheroids. When compared to ethosomes, PC/CHI showed higher cytotoxicity in MTT assay and live confocal microscopy showed cell disintegration after laser exposure. For 3-D spheroids, PC/CHI also showed higher cytotoxicity using acid phosphatase assay and a decrease in spheroid size was observed using light microscopy. In conclusion, both types of nanocarriers can be used for their potential treatment of SCC using PDT depending on the tumour localization in the skin.