Increased expression of epidermal fatty acid binding protein, cofilin, and 14-3-3-sigma (stratifin) detected by two-dimensional gel electrophoresis, mass spectrometry and microsequencing of drug-resistant human adenocarcinoma of the pancreas.

In order to study possible mechanisms leading to chemoresistance in pancreatic adenocarcinoma we examined the global protein expression of pancreatic cancer cells in vitro. We used a cell culture model derived from the adenocarcinoma of the pancreas (EPP85-181P). A classical multidrug-resistant subline, EPP85-181RDB, selected in presence of daunorubicin, and an atypical multidrug-resistant cell variant, EPP85-181RNOV, selected in presence of mitoxantrone, were analyzed using two-dimensional electrophoresis. After staining and image analysis, spots of interest were isolated using preparative two-dimensional electrophoresis and subjected to mass spectrometry and microsequencing. Three proteins, E-FABP, cofilin, and 14-3-3-sigma (stratifin), were overexpressed in chemoresistant cell lines. Cofilin was present in both multidrug in chemoresistant cell lines. Cofilin was present in both multidrug-resistant cell lines. E-FABP and 14-3-3-sigma (stratifin) was found to be overexpressed only in the mitoxantrone-selected atypical multidrug-resistant cell line. The possible significance of these findings is discussed.     

Study of the development of thermoresistance in human pancreatic carcinoma cell lines using proteome analysis

In order to find candidate proteins that are potentially associated with the thermoresistant phenotype in combination with drug resistance, we analyzed the differential protein expression in vitro in the human pancreatic cancer cell line EPP85-181-P and classical and atypical multidrug-resistant variants and their thermoresistant counterparts using proteomics. This study identifies sets of proteins that may lead to the development of thermoresistance. These results provide a fundamental basis to elucidate the molecular mechanism of thermoresistance and chemoresistance phenomena that may assist the therapy of inoperable cancers.     

Inhibition of cell proliferation by a resveratrol analog in human pancreatic and breast cancer cells

Resveratrol has been reported to possess cancer preventive properties. In this study, we analyzed anti-tumor activity of a newly synthesized resveratrol analog, cis-3,4'',5-trimethoxy-3''-hydroxystilbene (hereafter called 11b) towards breast and pancreatic cancer cell lines. 11b treatments reduced the proliferation of human pancreatic and breast cancer cells, arrested cells in the G2/M phase, and increased the percentage of cells in the subG1/G0 fraction. The 11b treatments also increased the total levels of mitotic checkpoint proteins such as BubR1, Aurora B, Cyclin B, and phosphorylated histone H3. Mechanistically, 11b blocks microtubule polymerization in vitro and it disturbed microtubule networks in both pancreatic and breast cancer cell lines. Computational modeling of the 11b-tubulin interaction indicates that the dimethoxyphenyl group of 11b can bind to the colchicine binding site of tubulin. Our studies show that the 11b treatment effects occur at lower concentrations than similar effects associated with resveratrol treatments and that microtubules may be the primary target for the observed effects of 11b. These studies suggest that 11b should be further examined as a potentially potent clinical chemotherapeutic agent for treating pancreatic and breast cancer patients.     

Ability of simple organotin polyethers to inhibit pancreatic cancer

A wide variety of organotin polyethers derived from the interfacial polymerization of dibutyltin dichloride and non-cancer inhibitory diols show decent to good inhibition of two human pancreatic cancer cell lines. In view of the general lack of ability of tested compounds to inhibit pancreatic cancer cell lines, this is significant. These cell lines are the AsPC-1 pancreatic cancer cell line which is an adenocarcinoma pancreatic cell line and the PANC-1 pancreatic cancer cell line which is an epithelioid carcinoma pancreatic cell line. The dibutyltin polyethers generally both exhibit EC₅₀ values in the same range and lower than cisplatin and higher CI₅₀ values than cisplatin. Essentially all of the polymers derived from simple non-aromatic diols showed CI₅₀ values greater than 2.     

Design,synthesis, cytotoxicity and 3D-QSAR analysis of new 3,6-disubstituted-1,2,4,5-tetrazine derivatives as potential antitumor agents

We synthesized two new series of 3-substituted-6-(2,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazines and analysed them for a potential role as antitumor agents. Twenty-two compounds were obtained, and four molecular structures were determined by X-ray diffraction analysis. Using flow cytometry and MTT assay, potential action on cell toxicity was determined for each of the compounds for four cancer cell lines. The potency and selectivity demonstrated by these compounds are dependent on the cancer cell line, where the following compounds were found the most promising agents against certain cell lines: compounds 1i and 1j for HL-60 cells, 1a and 1b on HCT116 cells, 1f on Hela cells and 2h on H1975 cells. The action exerted by these compounds is comparable to the well-known cancer treatment drug etoposide and higher than vatalanib. To arrive at the structural requirements for activity on each cell line, a SAR and 3D-QSAR analysis was carried out. From the 3D-QSAR models, steric and electronic features were identified in the aromatic centres, and were key components for cytotoxic activity on HL-60 cell lines. The cytometry results suggest that some tetrazine derivatives induce apoptosis on HCT116 cells.     

Resveratrol-induced cell inhibition of growth and apoptosis in MCF7 human breast cancer cells are associated with modulation of phosphorylated akt and caspase-9

Resveratrol (trans-3,4N,-5-trihydroxystilbene), a phytoalexin present in grapes and red wine, is emerging as a natural compound with potential anticancer properties. Here we show that resveratrol affects the growth of human breast cancer cell lines MCF7, MDA-MB-231, SK-BR-3, and Bcap-37 in a dose-dependent manner and that MCF7 is the most sensitive among the four cell lines. MCF7 cells treated with resveratrol showed typical characteristics of apoptosis including the poly (ADP-ribose) polymerase cleavage, TdT-mediated dUTP nick end labeling-positive staining, and morphologic changes. Phosphorylation of the oncogene product Akt was significantly reduced followed by decreased phosphorylation and increased processing of pro-caspase-9 on resveratrol treatment. These results indicate that resveratrol seems to exert its growth-inhibitory/apoptotic effect on the breast cancer cell line MCF7 via the Akt-caspase-9 pathway.     

Tacrine-Coumarin Derivatives as Topoisomerase Inhibitors with Antitumor Effects on A549 Human Lung Carcinoma Cancer Cell Lines

A549 human lung carcinoma cell lines were treated with a series of new drugs with both tacrine and coumarin pharmacophores (derivatives 1a–2c) in order to test the compounds’ ability to inhibit both cancer cell growth and topoisomerase I and II activity. The ability of human topoisomerase I (hTOPI) and II to relax supercoiled plasmid DNA in the presence of various concentrations of the tacrine-coumarin hybrid molecules was studied with agarose gel electrophoresis. The biological activities of the derivatives were studied using MTT assays, clonogenic assays, cell cycle analysis and quantification of cell number and viability. The content and localization of the derivatives in the cells were analysed using flow cytometry and confocal microscopy. All of the studied compounds were found to have inhibited topoisomerase I activity completely. The effect of the tacrine-coumarin hybrid compounds on cancer cells is likely to be dependent on the length of the chain between the tacrine and coumarin moieties (1c, 1d = tacrine-(CH₂)_8–9-coumarin). The most active of the tested compounds, derivatives 1c and 1d, both display longer chains.     

Synthesis,Cytotoxic Activity Evaluation of Novel 1,2,3‐Triazole Linked Quinazoline Derivatives

A series of novel 1,2,3‐triazole‐quinazoline derivatives were synthesized in five steps starting from anthranilamide by conventional methods. All the title compounds 10a — 10r were evaluated for cytotoxic activity against four human cancer cell lines (MGC ‐803, EC ‐109, MCF ‐7 and HGC ‐27) using MTT assay in vitro . Some of the synthesized compounds exhibited moderate to potent activity against tested cancer cell lines. Among them, compounds 10 h and 10q exhibited excellent growth inhibition against HGC ‐27 and compound 10 m also possessed excellent activity against MCF ‐7, with IC₅₀ values less than 1 µmol/L. Especially, compound 10 h was more cytotoxic than 5‐fluorouracil against all tested four human cancer cell lines.     

Epithelial-to-Mesenchymal Transition Is Not a Major Modulating Factor in the Cytotoxic Response to Natural Products in Cancer Cell Lines

Numerous natural products exhibit antiproliferative activity against cancer cells by modulating various biological pathways. In this study, we investigated the potential use of eight natural compounds (apigenin, curcumin, epigallocatechin gallate, fisetin, forskolin, procyanidin B2, resveratrol, urolithin A) and two repurposed agents (fulvestrant and metformin) as chemotherapy enhancers and mesenchymal-to-epithelial (MET) inducers of cancer cells. Screening of these compounds in various colon, breast, and pancreatic cancer cell lines revealed anti-cancer activity for all compounds, with curcumin being the most effective among these in all cell lines. Although some of the natural products were able to induce MET in some cancer cell lines, the MET induction was not related to increased synergy with either 5-FU, irinotecan, gemcitabine, or gefitinib. When synergy was observed, for example with curcumin and irinotecan, this was unrelated to MET induction, as assessed by changes in E-cadherin and vimentin expression. Our results show that MET induction is compound and cell line specific, and that MET is not necessarily related to enhanced chemosensitivity.     

Tetracyclic Thioxanthene Derivatives: Studies on Fluorescence and Antitumor Activity

Thioxanthones are bioisosteres of the naturally occurring xanthones. They have been described for multiple activities, including antitumor. As such, the synthesis of a library of thioxanthones was pursued, but unexpectedly, four tetracyclic thioxanthenes with a quinazoline–chromene scaffold were obtained. These compounds were studied for their human tumor cell growth inhibition activity, in the cell lines A375-C5, MCF-7 and NCI-H460. Photophysical studies were also performed. Two of the compounds displayed GI₅₀ values below 10 µM for the three tested cell lines, and structure–activity relationship studies were established. Three compounds presented similar wavelengths of absorption and emission, characteristic of dyes with a push-pull character. The structures of two compounds were elucidated by X-ray crystallography. Two tetracyclic thioxanthenes emerged as hit compounds. One of the two compounds accumulated intracellularly as a bright fluorescent dye in the green channel, as analyzed by both fluorescence microscopy and flow cytometry, making it a promising theranostic cancer drug candidate.     

Synthesis and Antitumor Activity Evaluation of Pyrimidine Analogues Bearing Urea Moiety

A series of 4‐anilino‐6‐phenylpyrimidines containing urea moiety were synthesized and the structures of all products were confirmed by ¹H NMR, ¹³C NMR and HRMS. The antiproliferative activities of these compounds were evaluated against three human tumor cell lines (MGC‐803, MCF‐7 and EC‐109) by applying the MTT assay method. compounds 4a , 4b and 6a showed the most effective activity, among which, 6a was more cytotoxic than 5‐fluorouracil against all tested human cancer cell lines with IC₅₀ values ranging from 1.80 to 2.72 µmol·L^?1.     

Metal-based anticancer agents: targeting androgen-dependent and androgen-independent prostate and COX-positive pancreatic cancer cells by phenanthrenequinone semicarbazone and its metal complexes

A planar, polycyclic and aromatic hydrocarbon ligand, namely 9,10-phenanthrenequinone semicarbazone, and its transition metal complexes have been synthesized and structurally characterized. The in vitro antiproliferative activity of these compounds against five human cancer cell lines revealed that they were effective against androgen receptor-positive/negative prostate cancer cells as well as COX-positive pancreatic BxPC-3 cancer cell line. The driving force behind such antiproliferative activity seems to be the up-regulated COX expression in these cells, which was amenable for targeting through metal complexation. These structural motifs can, therefore, serve as a starting point for developing novel cytotoxic agents against the growing number of prostate and pancreatic cancers.     

Evaluation of antiproliferative effect in vitro of some 2-amino-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole derivatives

New compounds of N-substituted 2-amino-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole set were synthesized and tested for their antiproliferative activity as part of our research in the antitumour field. Title compounds were obtained by reaction of sulfinylbis(2,4-dihydroxythiobenzoyl) (STB) with 4-substituted 3-thiosemicarbazides. The structures of compounds were identified from elemental, IR, 1H-, 13C-NMR and MS spectra analyses. The cytotoxicity in vitro against human bladder cancer HCV29T cells was determined. The most active compounds were also tested against human cancer cell lines: SW707 (rectal), A549 (lung) and T47D (breast). The antiproliferative effect of some compounds was higher than cisplatin studied comparatively.     

Proapoptotic Effect and Molecular Docking Analysis of Curcumin–Resveratrol Hybrids in Colorectal Cancer Chemoprevention

Different hybrids based on curcumin and resveratrol were previously synthesized and characterized by spectroscopic techniques. The most active molecules (3a, 3e, 3i, and 3k) were evaluated in vitro as an approach to determine the possible mechanism of action of the hybrids. The results indicated that the evaluated curcumin/resveratrol hybrids induce mitochondrial instability in SW620 and SW480 cells. Moreover, these molecules caused a loss in membrane integrity, suggesting an apoptotic process mediated by caspases after the treatment with compounds 3i (SW480) and 3k (SW620). In addition, the results suggest that the mechanism of action of the hybrids could be independent of the p53 status. Furthermore, hybrids 3e and 3i caused G0/G1 phase arrest, which highlights the potential of these molecules not only as cytotoxic but also as cytostatic compounds. Hybrids 3e and 3i caused a negative modulation of the matrix metalloproteinase 7 (MMP7) on SW480 cells. These curcumin resveratrol hybrids could be potential candidates for further investigations in the search for potential chemopreventive agents, even in those cases with resistance to conventional chemotherapy because of the lack of p53 expression or function. Molecular docking simulations showed that compounds 3e, 3i, and 3k bind efficiently to proapoptotic human caspases 3/7 proteins, as well as human MMP-7 and p53, which, in turn, could explain at the molecular level the in vitro cytotoxic effect of these compounds in SW480 and SW620 colon cancer cell lines.     

Synthesis and in vitro antitumor activity of 1,3,4-oxadiazole derivatives based on benzisoselenazolone

A series of novel 1,3,4-oxadiazole derivatives based on benzisoselenazolone has been prepared and tested for antiproliferative activity in vitro against the cells of human cancer cell lines: SSMC-7721 (human liver cancer cell), MCF-7 (human breast cancer cell) and A549 (human lung cancer cell). All the compounds obtained exhibited antiproliferative activity and showed selective cytotoxicity against different cancer cells. Compounds 7d and 7i showed significant antiproliferative activities against MCF-7 cells, with IC50 values of 1.07 and 1.76?μM respectively. Compound 7d were found to be the most potent compound against SSMC-7721 cells, with IC50 values 4.46?μM.     

A new series of titanocene dichloride derivatives bearing cyclic alkylammonium groups: Assessment of their cytotoxic properties

Ten new water soluble titanocene dichloride derivatives have been synthesized and characterized and their cytotoxicities against the human lung cancer cell line A549 have been assessed. The potencies of the compounds vary greatly, but dicationic 3-picolylium and 4-picolylium compounds exhibit IC₅₀ values that are unusually low for this class of compounds. In view of their potency against A549 cells, three of the new complexes were tested further on additional human cell lines including the small cell lung cancer cell line H69, the widely used cervical carcinoma cell line HeLa, the ovarian carcinoma cell line A2780 and its cisplatin resistant derivative A2780/CP. All three compounds exhibited potencies in all cell lines comparable to or better than those observed with the A549 cells, while one complex is actually more potent than cisplatin for HeLa cells.     

Synthesis and in vitro cytotoxic evaluation of aminoquinones structurally related to marine isoquinolinequinones

The synthesis of 4-methoxycarbonyl-3-methylisoquinolinequinone (1) and a variety of its substitution products with amino-, alkylamino and halogen groups on the quinone nucleus is reported. The series of 6-, 7- and 6,7-subtituted isoquinolinequinones were evaluated in vitro for their cytotoxic activity using the MTT colorimetric method. All the newly synthesized compounds showed moderate to high potency against MRC-5 healthy lung fibroblasts and four human tumor cell lines: AGS gastric adenocarcinoma, SK-MES-1 lung, J82 bladder carcinoma, and HL-60 leukemia cells. Among the series, compounds 4b, 12 and 13 exhibited interesting antitumor activity against human gastric adenocarcinoma, human lung and human bladder carcinoma cancer cells. 7-Amino-6-bromoisoquinoline-5,8-quinone (13) was found to be the most promising active compound against the tested cancer cell lines, with IC?? values in the 0.21-0.49 μM range, lower than the anti-cancer agent etoposide used as reference.     

1-Benzamido-1,4-dihydropyridine derivatives as anticancer agents: in vitro and in vivo assays

1,4-Dihydropyridine is a privileged scaffold present in many bioactive molecules, from coenzymes to commercially available drugs. Among other interesting properties, it has been found good anticancer activity in some of these 1,4-DHPs, therefore many research groups are trying to develop new compounds based on this structural core.For this purpose, in this work, a family of 23 new 1,4-dihydropyridines has been synthesized using hydrazide and malononitrile derivatives as precursors. This straightforward catalytic process has given rise to the desired products with moderate to excellent yields. All the compounds have been tested against four different cancer cell lines [HeLa (human cervical carcinoma), Jurkat (leukemia), A549 (human lung cancer) and MIA PaCa-2 (pancreatic cancer)] to establish a preliminary structure–activity relationship. From this study, and among the best candidates, we chose 4-chlorophenyl and 4-(trifluoromethyl)phenyl derivatives in the malononitrile ring to synthesize a second generation of molecules with enhanced cytotoxicity, modifying the substituent in the N-heterocyclic position (acylhydrazine moieties). With this second generation of compounds, we successfully decreased the IC₅₀ until 7 µM.An in-depth analysis of their biological properties suggests that these promising compounds trigger a non-conventional cell death mechanism known as paraptosis. Moreover, the tested photophysical properties of these products show in some cases an interesting long wavelength emission and excitation, potentially leading to new biosensors or theragnostic agents.Finally, in vivo assays concerning the acute toxicity in mice of two of the most active compounds (with an alkyl chain of seven carbon atoms in the acylhydrazine moiety) demonstrated that even dosed at thousands fold the corresponding IC₅₀ values (2500 and 3300 times more concentrated than the IC₅₀ values for the two compounds studied), there was no sign of harmful effects on the tested subjects, results that support their use in further studies to discover new anticancer drugs.     

Uses of ethyl benzoylacetate for the synthesis of thiophene,thiazole, pyridine,and pyran derivatives with antitumor activities

The reaction of ethyl benzoylacetate with malononitrile in an oil bath at 120°C gave the condensation product 3. The latter compound underwent a series of heterocyclization to give thiophene, thiazole, pyridine, and pyran derivatives. The structures of the synthesized products were established on the basis of analytical and spectral data. The antitumor evaluation of the newly synthesized products against the six cancer cell lines namely human gastric cancer (NUGC and HR), human colon cancer (DLD1), human liver cancer (HA22T and HEPG2), human breast cancer (MCF), nasopharyngeal carcinoma (HONE1), and normal fibroblast cells (WI38) indicated that many compounds expressed high inhibition against the six cancer cell lines. Compounds 3, 8a, 8c, 14b, 16b, 16c, 16d, 19a, 19b, 20a, 22a, 27b, and 28a were the most cytotoxic compounds among the tested compounds.