Oral Anticancer Heterobimetallic PtIV−AuI Complexes Show High In Vivo Activity and Low Toxicity

Au^I-carbene and Pt^IV−Au^I-carbene prodrugs display low to sub-μM activity against several cancer cell lines and overcome cisplatin (cisPt) resistance. Linking a cisPt-derived Pt^IV(phenylbutyrate) complex to a Au^I-phenylimidazolylidene complex 2 , yielded the most potent prodrug. While in vivo tests against Lewis Lung Carcinoma showed that the prodrug Pt^IV(phenylbutyrate)-Au^I-carbene ( 7 ) and the 1 : 1 : 1 co-administration of cisPt: phenylbutyrate: 2 efficiently inhibited tumor growth (≈95 %), much better than 2 (75 %) or cisPt (84 %), 7 exhibited only 5 % body weight loss compared to 14 % for 2 , 20 % for cisPt and >30 % for the co-administration. 7 was much more efficient than 2 at inhibiting TrxR activity in the isolated enzyme, in cells and in the tumor, even though it was much less efficient than 2 at binding to selenocysteine peptides modeling the active site of TrxR. Organ distribution and laser-ablation (LA)-ICP-TOFMS imaging suggest that 7 arrives intact at the tumor and is activated there.     

Resistance to anticancer drugs permanently alters electrophoretic mobility of cancer cell lines

Electrophoretic mobility is a physical phenomenon defining the mobility of charged particles in a solution under applied electric field. As charged biological systems, living cells including both prokaryotes and eukaryotes have been assessed in terms of electrophoretic mobility to decipher their electrochemical structure. Moreover, determination of electrophoretic mobility of living cancer cells have promoted the advance exploration of the nature of the cancer cells and separation of cancer cells from normal ones under applied electric field. However, electrophoretic mobility of drug‐resistant cells has not yet been examined. In the present study, we determined the electrophoretic mobility of drug‐resistant cancer cell lines for both suspension and adherent cells and compared with those of drug‐sensitive counterparts. We showed that resistance to anticancer drugs alters the electrophoretic mobility in a permanent manner, even lasting without any exposure to anticancer agents for a long time period. We also studied the cellular morphologies of adherent cells where the cellular invaginations and protrusions were increased in drug‐resistant adherent cells, which could be direct cause of altered surface charge and electrophoretic mobility as a result. These findings could be helpful in terms of understanding the electrophysiological and physicochemical background of drug resistance in cancer cells and developing systems to separate drug‐sensitive cells from drug‐resistant ones.     

Synthesis and Biological Evaluation of Amide Derivatives of Imidazopyridine as Anticancer Agents

A series of new amide derivatives of imidazopyridine is synthesized and structures of the products are confirmed by ¹H and ¹³C NMR, and mass spectral data. The synthesized derivatives are screened for their anticancer activity against four human cancer cell lines: lung cancer (A549), breast cancer (MCF-7), melanoma cancer (A375), and colon cancer (HT-29). Six synthesized compounds exhibit more potent activity than the control drug.

     

Synthesis and cytotoxic evaluation of novel brominated N-alkyl pyrano[3,2-c]quinolinones

A novel series of 6-alkyl-4-bromopyrano[3,2-c]quinoline-2,5-diones ( 2a–c ), 6-alkyl-3,4-dibromopyrano[3,2-c]quinoline-2,5-diones ( 4a–c ), and 6-alkyl-3-amino-bromopyrano[3,2-c]quinoline-2,5-diones ( 6a–c ) were synthesized via appropriate conventional methods and in good yields. The structures of target compounds were approved by elemental analysis, IR, ¹H NMR, ¹³C NMR, and mass spectrometry. The antitumor inhibitory activities of the new compounds were evaluated on several cancer cell lines, A-549 (human lung cancer), HCT-116 (human colon cancer), MCF-7 (breast cancer), and HePG-2 (human liver cancer). Moreover, 50% inhibitory concentrations, IC₅₀, were established. 5-Fluorouracil was used as a positive control in the viability assay. The screening results showed that most of the examined compounds exposed powerful inhibition activity toward various cell lines. Particularly, Compound 4c exhibited higher cytotoxic activity against four tumor cell lines than the reference drug, 5-fluorouracil, with significantly lower IC₅₀ values. Accordingly, most of the synthesized compounds would be a better prospective growth in the anticancer drug discovery.     

Iodine-catalyzed three-component one-pot synthesis of novel 1,8-dioxo-decahydroacridines derivatives bearing benzene sulfonamide moiety

An efficient synthetic method for 1,8-dioxo-decahydroacridines derivatives bearing the biologically active sulfonamide moiety is described. Aromatic aldehyde reacted with 5,5-dimethyl-1,3-cyclohexanedione and sulfanilamide, with molecular iodine as catalyst, to give 1,8-dioxo-decahydroacridines derivatives in high to excellent yield. The structures of these compounds were established on the basis of elemental (C, H and N) and spectral analysis (¹H NMR, ¹³C NMR, MS and FTIR). All the compounds were tested for their cytotoxic activity in vitro against three human tumor cell lines: human mammary cancer cells (MCF-7), human cervical carcinoma cells (Hela), and human lung cancer cells (A549) by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Most of them showed moderate to potent cytotoxic activity against the tested cell lines. Among them, the most active compound 4e exhibited more efficient activity (10.92 μM) against MCF-7 cells than cisplatin (11.06 μM).     

Design,Synthesis, and Biological Evaluation of 2‐(4‐Aminophenyl)benzothiazole Analogues as Antiproliferative Agents

A series of 28 novel 2‐(4‐aminophenyl)benzothiazole analogues have been synthesized and characterized using various analytical techniques like ¹H NMR, ¹³C NMR, electrospray ionization mass spectrometry, and IR and bioevaluated for their antiproliferative activity over a group of three human cancer cell lines, namely, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MDA‐MB‐231), using sulforhodamine B assay method. Few synthesized molecules ( 5a , 5c , 5d , 5f , 7b , and 7j ) displayed effective growth inhibition (GI₅₀) activity against the tested human cancer cell lines at lower micromolar concentration (GI₅₀) values in the range 0.2–1.7 μM. Noticeably, compound 7b exhibited reasonable activity in all three cancer cell lines in the GI₅₀ range 0.55–1.2 μM. Further, when 7b was screened for tubulin polymerization inhibition, it exhibited more than 55% inhibition at concentration of 5.0 μM. The molecular docking simulations supported the molecular interactions of the derivatives with the targeted receptor. These derivatives may serve as lead structures for development of potential anticancer drug candidates, and 7b might act as a potential microtubule polymerization inhibitor.     

Exploring Ovarian Cancer Cell Resistance to Rhenium Anticancer Complexes

Rhenium tricarbonyl complexes have been recently investigated as novel anticancer agents. However, little is understood about their mechanisms of action, as well as the means by which cancer cells respond to chronic exposure to these compounds. To gain a deeper mechanistic insight into these rhenium anticancer agents, we developed and characterized an ovarian cancer cell line that is resistant to a previously studied compound [Re(CO)₃(dmphen)(ptolICN)]⁺, where dmphen=2,9‐dimethyl‐1,10‐phenanthroline and ptolICN=para‐tolyl isonitrile, called TRIP. This TRIP‐resistant ovarian cancer cell line, A2780TR, was found to be 9 times less sensitive to TRIP compared to the wild‐type A2780 ovarian cancer cell line. Furthermore, the cytotoxicities of established drugs and other rhenium anticancer agents in the TRIP‐resistant cell line were determined. Notably, the drug taxol was found to exhibit a 184‐fold decrease in activity in the A2780TR cell line, suggesting that mechanisms of resistance towards TRIP and this drug are similar. Accordingly, expression levels of the ATP‐binding cassette transporter P‐glycoprotein, an efflux transporter known to detoxify taxol, were found to be elevated in the A2780TR cell line. Additionally, a gene expression analysis using the National Cancer Institute 60 cell line panel identified the MT1E gene to be overexpressed in cells that are less sensitive to TRIP. Because this gene encodes for metallothioneins, this result suggests that detoxification by this class of proteins is another mechanism for resistance to TRIP. The importance of this gene in the A2780TR cell line was assessed, confirming that its expression is elevated in this cell line as well. As the first study to investigate and identify the cancer cell resistance pathways in response to a rhenium complex, this report highlights important similarities and differences in the resistance responses of ovarian cancer cells to TRIP and conventional drugs.     

Self‐Assembly of Ambidentate Pyridyl‐Carboxylate Ligands with Octahedral Ruthenium Metal Centers: Self‐Selection for a Single‐Linkage Isomer and Anticancer‐Potency Studies

The synthesis of six new [2+2] metallarectangles through the coordination‐driven self‐assembly of octahedral Ru^II‐based acceptors with ambidentate pyridyl‐carboxylate donors is described. These molecular rectangles are fully characterized by ¹H NMR spectroscopy, high‐resolution electrospray mass spectrometry, and single‐crystal X‐ray diffraction. In each case, despite the possible formation of multiple isomers, based on the relative orientation of the pyridyl and carboxylate groups (head‐to‐head versus head‐to‐tail), evidence for the formation of a single preferred ensemble (head‐to‐tail) was found in the ¹H NMR spectra. Furthermore, the cytotoxicities of all of the rectangles were established against A549 (lung), AGS (gastric), HCT‐15 (colon), and SK hep 1 (liver) human cancer cell lines. The cytotoxicities of rectangles that contained the 5,8‐dihydroxy‐1,4‐naphthaquinonato bridging moiety between the Ru centers ( 9 – 11 ) were particularly high against AGS cancer cells, with IC₅₀ values that were comparable to that of reference drug cisplatin.     

Artemisia santolinifolia-Mediated Chemosensitization via Activation of Distinct Cell Death Modes and Suppression of STAT3/Survivin-Signaling Pathways in NSCLC

Conventional chemotherapy remains an integral part of lung cancer therapy, regardless of its toxicity and drug resistance. Consequently, the discovery of an alternative to conventional chemotherapy is critical. Artemisia santolinifolia ethanol extract (AS) was assessed for its chemosensitizer ability when combined with the conventional anticancer drug, docetaxel (DTX), against non-small cell lung cancer (NSCLC). SRB assay was used to determine cell viability for A549 and H23 cell lines. The potential for this combination was examined by the combination index (CI). Further cell death, analyses with Annexin V/7AAD double staining, and corresponding protein expressions were analyzed. Surprisingly, AS synergistically enhanced the cytotoxic effect of DTX by inducing apoptosis in H23 cells through the caspase-dependent pathway, whereas selectively increased necrotic cell population in A549 cells, following the decline in GPX4 level and reactive oxygen species (ROS) activation with the highest rate in the combination treatment group. Furthermore, our results highlight the chemosensitization ability of AS when combined with DTX. It was closely associated with synergistic inhibition of oncogenesis signaling molecule STAT3 in both cell lines and concurrently downregulating prosurvival protein Survivin. Conclusively, AS could enhance DTX-induced cancer cells apoptosis by abrogating substantial prosurvival proteins’ expressions and triggering two distinct cell death pathways. Our data also highlight that AS might serve as an adjunctive therapeutic option along with a conventional chemotherapeutic agent in the management of NSCLC patients.     

Synthesis,in vitro biological evaluation and in silico docking studies of new quinazolin-2,4-dione analogues as possible anticarcinoma agents

Today, cancer is considered as one of the major reasons of death in human beings worldwide. We reported herein the synthesis, anticancer activity, and in silico docking studies of a series of nine quinazolindione-based scaffolds bearing pyrimidine, pyridine, pyran, and pyrazole moieties ( 1 - 9 ) through Michael addition, Vilsmeier-Haack, Claisen-Schmidt, and nucleophilic addition reactions. The chemical structures of the newly prepared compounds were ascertained by means of their spectral analysis techniques like IR, ¹H-nuclear magnetic resonance (NMR), ¹³C-NMR, mass spectroscopy, and elemental analysis. This work was conducted to investigate the implication of Rho7 protein in breast and hepatocellular cancer cells aggressively. MCF-7 and HepG2 cells have been selected as models for the effect of protein expression on breast and hepatocellular cancers cell growth. All prepared compounds were biologically evaluated for their antiproliferative efficacy on hepatic cancer cell lines (HepG2) and breast cancer cell lines (MCF-7); also, their effects on normal cell lines (BALB/3T3) were studied. Moreover, in silico molecular docking studies were studied for the compounds against the binding site of Homo sapiens Rho7 protein. The pharmacokinetic properties of the newer compounds were also evaluated using various computational tools. The compounds showed interesting interactions with satisfactory docking scores to the target Rho7; thus, they may act as promising potent drug candidates against cancer.     

Metabolic Studies of Tumor Cells Using [1-13C] Pyruvate Hyperpolarized by Means of PHIP-Side Arm Hydrogenation

The kinetics of metabolic processes can be assessed, in real time by means of MR hyperpolarized (HP) metabolites. [1-¹³C]pyruvate, hyperpolarized by means of d-DNP, is, by far, the substrate most widely applied to the investigation of several pathologies characterized by deregulated glycolytic metabolic networks, including cancer. Hyperpolarization of [1-¹³C]pyruvate by means of the cost effective, fast and easy to handle PHIP-SAH (para-hydrogen induced polarization-side arm hydrogenation) method opens-up a pathway for the application of HP metabolites to a wide range of cancer-related studies. Herein, we report the first application of PHIP-SAH hyperpolarized [1-¹³C]pyruvate in the investigation of upregulated glycolysis in two murine breast cancer cell lines (168FARN and 4T1). The results obtained using HP pyruvate have been validated with a conventional biochemical assay and are coherent with previously-reported lactate dehydrogenase activity measured in those cells.     

Microwave-assisted synthesis of derivatives of khellinone under phase-transfer catalytic conditions

The microwave-assisted synthesis of four new 5-acetyl-4,7-dimethoxy-6-hydroxybenzofuran (khellinone) analogs is described. The structures of the obtained derivatives in the solid state are evaluated on the basis of ¹³C CP/MAS NMR spectra and theoretical calculations at DFT level. A single crystal X-ray diffraction structure is presented for 8-acetyl-7-hydroxy-4-methylcoumarin. 1,4-Bis(5-acetyl-4,7-dimethoxybenzofuran-6-yloxy)butane was evaluated for potential anticancer activity in an in vitro screening panel of 60 human tumor cell lines. Selected leukemia, non-small cell lung cancer, CNS, melanoma, ovarian, and breast cancer cell lines were sensitive to this compound.     

Synthesis,computational quantum chemical study,in silico ADMET and molecular docking analysis,in vitro biological evaluation of a novel sulfur heterocyclic thiophene derivative containing 1,2,3-triazole and pyridine moieties as a potential human topoisomerase IIα inhibiting anticancer agent

Computational quantum chemical study and biological evaluation of a synthesized novel sulfur heterocyclic thiophene derivative containing 1,2,3-triazole and pyridine moieties namely BTPT [2-(1-benzyl-5-methyl-1H-1,2,3-triazol-4-yl)-6-methoxy-4-(thiophen-2-yl) pyridine] was presented in this study. The crystal structure was determined by SCXRD method. For the title compound BTPT, spectroscopic characterization like ¹H NMR, ¹³C NMR, FTIR, UV–vis were carried out theoretically by computational DFT method and compared with experimental data. Druglikeness parameters of BTPT were found through in silico pharmacological ADMET properties estimation. The molecular docking investigation was performed with human topoisomerase IIα (PDB ID:1ZXM) targeting ATP binding site. In vitro cytotoxicity activity of BTPT/doxorubicin were examined by MTT assay procedure against three human cancer cell lines A549, PC-3, MDAMB-231 with IC50 values of 0.68/0.70, 1.03/0.77 and 0.88/0.98 μM, respectively. Our title compound BTPT reveals notable cytotoxicity against breast cancer cell (MDAMB-231), moderate activity with human lung cancer cell (A-549) and less inhibition with human prostate cancer cell (PC-3) compared to familiar cancer medicine doxorubicin. From the results, BTPT could be observed as a potential candidate for novel anticancer drug development process.     

MUC1 Aptamer-Capped Mesoporous Silica Nanoparticles for Navitoclax Resistance Overcoming in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. In the last years, navitoclax has emerged as a possible treatment for TNBC. Nevertheless, rapid navitoclax resistance onset has been observed thorough Mcl-1 overexpression. As a strategy to overcome Mcl-1-mediated resistance, herein we present a controlled drug co-delivery system based on mesoporous silica nanoparticles (MSNs) targeted to TNBC cells. The nanocarrier is loaded with navitoclax and the Mcl-1 inhibitor S63845 and capped with a MUC1-targeting aptamer ( apMUC1-MSNs(Nav/S63845) ). The apMUC1-capped nanoparticles effectively target TNBC cell lines and successfully induce apoptosis, overcoming navitoclax resistance. Moreover, navitoclax encapsulation protects platelets against apoptosis. These results point apMUC1-gated MSNs as suitable BH3 mimetics nanocarriers in the targeted treatment of MUC1-expressing TNBC.     

A Dual Killing Strategy: Photocatalytic Generation of Singlet Oxygen with Concomitant PtIV Prodrug Activation

A ruthenium‐based mitochondrial‐targeting photosensitiser that undergoes efficient cell uptake, enables the rapid catalytic conversion of Pt^IV prodrugs into their active Pt^II counterparts, and drives the generation of singlet oxygen was designed. This dual mode of action drives two orthogonal cancer‐cell killing mechanisms with temporal and spatial control. The designed photosensitiser was shown to elicit cell death of a panel of cancer cell lines including those showing oxaliplatin‐resistance.     

Synthesis and In Vitro Anticancer Evaluation of Symmetrically Bridged 1,3‐thiazine Derivatives

A series of bis‐1,3‐thiazine derivatives 3a–o were synthesized from the condensation reactions of symmetric dialdehydes 1a–c possessing aliphatic ether spacer units with 3‐substituted‐amino‐2‐cyano‐3‐mercaptoacrylamides 2a–e . The chemical structures of the products were fully characterized by using different spectroscopic techniques, such as ¹H NMR, ¹³C NMR, IR, electron impact mass spectrometry, and elemental analysis. Compounds 3a , 3f , and 3k underwent ring opening followed by recyclization and alkylation in basic medium to afford bis‐pyrimidinones 4a–c and 5a–c . The anticancer potential of the new bis‐1,3‐thiazines was assessed in vitro against six different human cell lines, including lung A549, colon HCT116, breast MCF‐7, prostate PC3, liver HepG2, and normal melanocyte HFB4. The results revealed a potent activity of compounds 3e and 3k against breast and liver cancer cell lines in comparison with the reference drug doxorubicin with no noticeable toxicity on normal cells.     

Metabolic Profiling of Human Colorectal Cancer Using High Resolution 1H Nuclear Magnetic Resonance Spectroscopy

Colorectal cancer (CRC) is the third commonest malignancy cancer worldwide. Clear understandings of global metabolic profiling of the normal mucosa and cancer tissues are vitally important to aid optimizing the clinical management strategy and understanding CRC biology. We studied metabolic characteristics of 20 CRC and 20 distant normal mucosa tissues extracts from 20 patients using high resolution ¹H NMR spectroscopy in conjunction with multivariate analyses, such as principal component analysis (PCA). Compared with distant normal mucosa tissues, lactate, taurine, ornithine and polyamine were present at significantly higher levels in CRC tissue extracts whereas myo‐inositol was present at significantly lower level. Two metabolites ratios such as myo‐inositol/taurine and myo‐inositol/(ornithine+polyamine) appear to be the most valuable biomarkers for the differentiation CRC from normal mucosa tissues. Our data suggested that HR ¹H NMR spectroscopy combined with multivariate analyses is a potentially useful technology for detecting malignant changes in the normal mucosa tissues, the technique may be further exploited for future CRC biomarker research or identification of targets for therapeutic manipulations.     

Monitoring the Glutathione Redox Reaction in Living Human Cells by Combining Metabolic Labeling with Heteronuclear NMR

The glutathione (GSH) redox reaction is critical for defense against cellular reactive oxygen species (ROS). However, direct and real‐time monitoring of this reaction in living mammalian cells has been hindered by the lack of a facile method. Herein, we describe a new approach that exploits the GSH biosynthetic pathway and heteronuclear NMR. [U‐¹³C]‐labeled cysteine was incorporated into GSH in U87 glioblastoma cells, and the oxidation of GSH to GSSG by a ROS‐producing agent could be monitored in living cells. Further application of the approach to cells resistant to temozolomide (TMZ), an anti‐glioblastoma drug, suggested a possible new resistance mechanism involving neutralization of ROS. This result was corroborated by the observation of up‐regulation of glutathione peroxidase 3 (GPx3). This new approach could be easily applied to redox‐dependent signaling pathways and drug resistance involving ROS.     

Novel Bis(1,2,4-oxadiazolyl) Fused Thiazole Derivatives: Synthesis and Anticancer Activity

A novel series of bis-1,2,4-oxadiazole fused benzothiazole derivatives 9a–9j are synthesized, and their structures are confirmed by ¹H and ¹³C NMR, and mass spectral data. All products are evaluated in vitro for their anticancer potential against a panel of four human cancer cell lines such as lung cancer (A549), breast carcinoma (MCF-7), melanoma (A375), and colon cancer (HT-29). The combretastatin-A4 is used as standard drug. All compounds 9a–9j exhibit significant anticancer activity with IC₅₀ values ranging from 0.11±0.01 to 14.6±3.89 μM. Among these, compounds 9a–9d, 9h, 9i demonstrate more potent activity than the control.