Novel 1,2,4-triazole derivatives as potential anticancer agents: Design,synthesis, molecular docking and mechanistic studies

A series of novel compounds carrying 1,2,4-triazole scaffold was synthesized and evaluated for their anticancer activity against a panel of cancer cell lines using MTT assay. Compounds 8a, 8b, 8c, 8d, 10b, 10e, and 10 g showed remarkable antiproliferative activity against the tested cell lines. Compounds 8a, 8b, 8c, 8d, 10b, 10e, and 10 g with the least IC₅₀ values in MTT assay were tested against three known anticancer targets including EGFR, BRAF and Tubulin. The results revealed that compounds 8c and 8d showed almost same BRAF inhibitory activity and were discovered to be potent inhibitors of cancer cell proliferation and were also observed to be strong Tubulin inhibitors. Moreover, 8c also showed the best EGFR inhibition with IC₅₀ = 3.6 μM. Finally molecular modeling studies were performed to explore the binding mode of the most active compounds to the target enzymes.     

Assessment of the antiproliferative and apoptotic roles of sulfonamide carbonic anhydrase IX inhibitors in HeLa cancer cell line

Carbonic anhydrase IX (CA IX) has recently been validated as an antitumor/antimetastatic drug target. In this study, we examined the underlying molecular mechanisms and the anticancer activity of sulfonamide CA IX inhibitors against cervical cancer cell lines. The effects of several sulfonamides on HeLa, MDA-MB-231, HT-29 cancer cell lines, and normal cell lines (HEK-293, PNT-1A) viability were determined. The compounds showed high cytotoxic and apoptotic activities, mainly against HeLa cells overexpressing CA IX. We were also examined for intracellular reactive oxygen species (ROS) production; intra-/extracellular pH changes, for inhibition of cell proliferation, cellular mitochondrial membrane potential change and for the detection of caspase 3, 8, 9, and CA IX protein levels. Of the investigated sulfonamides, one compound was found to possess high cytotoxic and anti-proliferative effects in HeLa cells. The cytotoxic effect occurred via apoptosis, being accompanied by a return of pHe/pHi towards normal values as for other CA IX inhibitors investigated earlier.     

Methoxy and bromo scans on N-(5-methoxyphenyl) methoxybenzenesulphonamides reveal potent cytotoxic compounds,especially against the human breast adenocarcinoma MCF7 cell line

Thirty seven N-(5-methoxyphenyl)-4-methoxybenzenesulphonamide with methoxy or/and bromo substitutions (series 1-4) and with different substituents on the sulphonamide nitrogen have been synthesised. 21 showed sub-micromolar cytotoxicity against HeLa and HT-29 human tumour cell lines, and were particularly effective against MCF7. The most potent series has 2,5-dimethoxyanilines, especially the 4-brominated compounds 23–25. The active compounds inhibit microtubular protein polymerisation at micromolar concentrations, thus pointing at tubulin as the target. Co-treatment with the MDR inhibitor verapamil suggests that they are not MDR substrates. Compound 25 showed nanomolar antiproliferative potency. It severely disrupts the microtubule network in cells and arrests cells at the G₂/M cell-cycle phase, thus confirming tubulin targeting. 25 triggered apoptotic cell death, and induced autophagy. Docking studies suggest binding in a distinct way to the colchicine site. These compounds are promising new antitumor agents acting on tubulin.     

Cancer stem cells CD133 inhibition and cytotoxicity of certain 3-phenylthiazolo[3,2-a]benzimidazoles: design,direct synthesis,crystal study and in vitro biological evaluation

Cancer stem cells (CSCs) have been objects of intensive study since their identification in 1994. Adopting a structural rigidification approach, a novel series of 3-phenylthiazolo[3,2-a]benzimidazoles 4a–d was designed and synthesised, in an attempt to develop potent anticancer agent that can target the bulk of tumour cells and CSCs. The anti-proliferative activity of the synthesised compounds was evaluated against two cell lines, namely; colon cancer HT-29 and triple negative breast cancer MDA-MB-468 cell lines. Also, their inhibitory activity against the cell surface expression of CD133 was examined. In particular, compound 4b emerged as a promising hit molecule as it manifested good antineoplastic potency against both tested cell lines (IC₅₀?=?9 and 12?μM, respectively), beside its ability to inhibit the cell surface expression of CD133 by 50% suggesting a promising potential of effectively controlling the tumour by eradicating the tumour bulk and inhibiting the proliferation of the CSCs. Moreover, compounds 4a and 4c showed moderate activity against HT-29 (IC₅₀?=?21 and 29?μM, respectively) and MDA-MB-468 (IC₅₀?=?23 and 24?μM, respectively) cell lines, while they inhibited the CD133 expression by 14% and 48%, respectively. Finally, a single crystal X-ray diffraction was recorded for compound 4d.     

Discovery and optimization of 3,4,5-trimethoxyphenyl substituted triazolylthioacetamides as potent tubulin polymerization inhibitors

Based on our previous research, three series of new triazolylthioacetamides possessing 3,4,5-trimethoxyphenyl moiety were synthesized, and evaluated for antiproliferative activities and inhibition of tubulin polymerization. The most promising compounds 8b and 8j demonstrated more significant antiproliferative activities against MCF-7, HeLa, and HT-29 cell lines than our lead compound 6. Moreover, analogues 8f, 8j, and 8o manifested more potent antiproliferative activities against HeLa cell line with IC₅₀ values of 0.04, 0.05 and 0.16?μM, respectively, representing 100-, 82-, and 25-fold improvements of the activity compared to compound 6. Furthermore, the representative compound, 8j, was found to induce significant cell cycle arrest at the G₂/M phase in HeLa cell lines via a concentration-dependent manner. Meanwhile, compound 8b exhibited the most potent tubulin polymerization inhibitory activity with an IC₅₀ value of 5.9?μM, which was almost as active as that of CA-4 (IC₅₀?=?4.2?μM). Additionally, molecular docking analysis suggested that 8b formed stable interactions in the colchicine-binding site of tubulin.     

Synthesis and biological evaluation of 4beta-[(4-substituted)-1,2,3-triazol-1-yl]podophyllotoxins as potential anticancer agents

A series of novel 4beta-[(4-substituted)-1,2,3-triazol-1-yl]podophyllotoxin derivatives were synthesized by employing Cu(I)-catalyzed click chemistry and evaluated for their anticancer activity against a panel of seven human cancer cell lines (HT-29, HCT-15, 502713, HOP-62, A-549, MCF-7, and SF-295). The compounds 9b, 9c, 9e, 9f, and 9h showed significant cytotoxic activities especially against HT-29, HCT-15, 502713 cell lines.     

Synthesis,Characterization, and Biological Study of 3-Trifluoromethylpyrazole Tethered Chalcone-Pyrrole and Pyrazoline-Pyrrole Derivatives

The present study illustrates the design and synthesis of new series of 3-trifluoromethylpyrazole tethered chalcone-pyrrole and pyrazoline-pyrrole derivatives. All compounds were further screened for in vitro cytostatic activities on full NCI 60 cancer cell lines at National Cancer Institute, USA. Compounds (2E)-3-(1H-pyrrol-2-yl)-1-{4-[3-(trifluoromethyl)-1H-pyrazol-1-yl]phenyl}prop-2-en-1-one ( 5a ) and (2E)-1-{3-methyl-4-[3-(trifluoromethyl)-1H-pyrazol-1-yl]phenyl}-3-(1H-pyrrol-2-yl)prop-2-en-1-one ( 5c ) displayed significant antiproliferative activity (Growth Percentage: −77.10 and −92.13, respectively at 10 μM concentration) against the UO-31 cell lines from renal cancer and were further selected for assay at 10-fold dilutions of five different concentrations (10⁻⁴ to 10⁻⁸ M). Both compounds 5a and 5c exhibited promising antiproliferative activity (GI₅₀: 1.36 to 0.27 μM) against leukemia cancer cell lines HL-60 and RPMI-8226, colon cancer cell lines KM-12; breast cancer cell lines BT-549. Moreover, both compounds 5a and 5c were found to be non-cytotoxic (LC₅₀>100) against HL-60, RPMI-8226, and KM-12 cell lines. Remarkably, GI₅₀ values of compounds 5a and 5c were identified as more promising than sunitinib against most cancer cell lines. In silico study of compounds 5a and 5c exemplified the desired ADME properties for drug-likeness as well as tighter interactions with VEGFR-2. Hence, compounds 5a and 5c would be good cytotoxic agents after further clinical study.     

Synthesis and cytotoxic activities of novel copper and silver complexes of 1,3-diaryltriazene-substituted sulfonamides

In this study, a series of 10 novel copper (II) and silver complexes of 1,3-diaryltriazene-substituted sulfonamides was synthesised. All the synthesised ligands and their metal complexes were assessed for in vitro cytotoxicity against human colorectal adenocarcinoma (DLD-1), cervix carcinoma (HeLa), breast adenocarcinoma (MDA-MB-231), colon adenocarcinoma (HT-29), endometrial adenocarcinoma (ECC-1), prostate cancer (DU-145 and PC-3), normal embryonic kidney (HEK-293), normal prostate epithelium (PNT-1A), and normal retinal pigment epithelium (ARPE-19) cells. Most of the metal complexes from the series showed to be more active against all cancerous cells than the uncomplexed 1,3-diaryltriazene-substituted sulfonamides, and lower cytotoxic effects observed on normal cells. Most of the Cu (II) and Ag (I) metal complexes from the presented series showed high cytotoxic activity against HeLa cells with IC₅₀ values ranging from 2.08 to >300?µM. Specifically, compound L₃-Ag showed one of the highest cytotoxicity against all cancer cell lines with IC₅₀ values between 3.30 to 16.18?µM among other tested compounds.     

Structural Modification of Stilbenoids from Acanthopanax leucorrhizus and Their Cytotoxic Activity

A new cis‐stilbenoid, 1,9‐dihydroxy‐10‐methoxy‐6H‐dibenzo[b,f]oxocin‐6‐one ( 2 ) was isolated from the AcOEt extract of the stem barks of Acanthopanax leucorrhizus, along with three known stilbenoids, 9‐hydroxy‐10‐methoxy‐6H‐dibenzo[b,f]oxocin‐6‐one ( 1 ), 5‐O‐methyl‐(E)‐resveratrol 3‐O‐β‐d ‐glucopyranoside ( 3 ), and (E)‐resveratrol 3‐O‐β‐d ‐xylopyranoside ( 4 ). Two derivatives ( 2a and 2b ) were synthesized by the structural modification of compound 2, which exhibited certain cytotoxic activities against HT‐29 and HeLa cell lines in vitro. All compounds were structurally characterized by comprehensive analysis of their spectroscopic data and comparison with literature information, and evaluated for their cytotoxic activities against three human tumor cell lines (HL‐60, HT‐29, and HeLa) by the standard MTT assay in vitro. The results showed that derivatives 2a and 2b exhibited strong activities than compounds 2 against HT‐29 and HeLa cell lines.     

Development of 2-oindolin-3-ylidene-indole-3-carbohydrazide derivatives as novel apoptotic and anti-proliferative agents towards colorectal cancer cells

Mitochondrial anti-apoptotic Bcl2 and BclxL proteins, are overexpressed in multiple tumour types, and has been involved in the progression and survival of malignant cells. Therefore, inhibition of such proteins has become a validated and attractive target for anticancer drug discovery. In this manner, the present studies developed a series of novel isatin–indole conjugates (7a-j and 9a-e) as potential anticancer Bcl2 and BclxL inhibitors. The progression of the two examined colorectal cancer cell lines was significantly inhibited by all of the prepared compounds with IC₅₀ ranges132–611 nM compared to IC₅₀ = 4.6 µM for 5FU, against HT-29 and IC₅₀ ranges 37–468 nM compared to IC₅₀ = 1.5 µM for 5FU, against SW-620. Thereafter, compounds 7c and 7g were selected for further investigations. Interestingly, both compounds exhibited selective cytotoxicity against both cell lines with high safety to normal fibroblast (HFF-1). In addition, both compounds 7c and 7g induced apoptosis and inhibited Bcl2 and BclxL expression in a dose-dependent manner. Collectively, the high potency and selective cytotoxicity suggested that conjugates 7c and 7g could be a starting point for further optimisation to develop novel pro-apoptotic and antitumor agents towards colon cancer.     

Synthesis,Cytotoxicity and Antimicrobial Evaluation of New Coumarin‐Tagged β‐Lactam Triazole Hybrid

A series of coumarin‐tagged β‐lactam triazole hybrids ( 10a – 10o ) were synthesized and tested for their cytotoxic activity against MDA‐MB‐231 (triple negative breast cancer), MCF‐7 (estrogen receptor positive breast cancer (ER+)) and A549 (human lung carcinoma) cancer cell lines including one normal cell line, HEK‐293 (human embryonic kidney). Two compounds 10b and 10d exhibited substantial cytotoxic effect against MCF‐7 cancer cell lines with IC₅₀ values of 53.55 and 58.62 μm , respectively. More importantly, compounds 10b and 10d were non‐cytotoxic against HEK‐293 cell lines. Structure–activity relationship (SAR) studies suggested that the nitro and chloro group at the C‐3 position of phenyl ring are favorable for anticancer activity, particularly against MCF‐7 cell lines. Furthermore, antimicrobial evaluation of these compounds revealed modest inhibition of examined pathogenic strains with compounds 10c and 10i being the most promising antimicrobial agents against Pseudomonas aeruginosa and Candida albicans, respectively.     

Cellular isoform of the prion protein PrPc in human intestinal cell lines: genetic polymorphism at codon 129, mRNA quantification and protein detection in lipid rafts

The cellular isoform of the normal prion protein PrP(c), encoded by the PRNP gene, is expressed in human intestinal epithelial cells where it may represent a potential target for infectious prions. We have sequenced the PRNP gene in Caco-2 and HT-29 parental and clonal cell lines, and found that these cells have a distinct polymorphism at codon 129. HT-29 cells are homozygous Met/Met, whereas Caco-2 cells are heterozygous Met/Val. The 129Val variant was also detected in Caco-2 mRNAs. Real-time PCR quantifications revealed that PrP(c) mRNAs were more expressed in HT-29 cells than in Caco-2 cells. These data were confirmed by studying the expression of PrP(c) in plasma membranes and lipid rafts prepared from these cells. Overall, these results may be important in view of using human intestinal cell lines Caco-2 and HT-29 as cellular in vitro models to study the initial steps of prion propagation after oral inoculation.     

Anti-tumoral activity of imidazoquines,a new class of antimalarials derived from primaquine

The growth inhibitory activity of imidazoquines, antimalarial imidazolidin-4-ones derived from primaquine, on human cancer cell lines HT-29, Caco-2, and MCF-7 has been evaluated. Primaquine, N-dipeptidyl-primaquine derivatives, and other quinolines have been included in the study for comparison purposes. Primaquine and some of its derivatives were significantly active against the MCF-7 human breast cancer cell line, so these compounds might represent useful leads targeted at the development of novel specific agents against breast cancer. Conversely, all compounds were generally inactive against HT-29, with only one of the imidazoquines having IC₅₀ below 50 μM. Activities against the Caco-2 cell line were modest and did not follow any defined trend.     

Cytotoxic activity of new racemic and optically active N-phosphonoalkyl bicyclic β-amino acids against human malignant cell lines

The cytotoxic effects of novel racemic and optically active constrained N-phosphonoalkyl bicyclic β-amino acids were tested against a panel of human tumor cell lines. All of the compounds investigated exhibited different concentration-dependent antiproliferative effects against the HT-29, MDA-MB-231, HepG2 and HeLa cell lines after 24?h treatment. The most sensitive cells were the HeLa cells at various concentrations of the four compounds tested. The aminophosphonate 3 exerted the most pronounced antiproliferative effect against the HeLa cells (inhibition of the cell vitality up to 70% at 0.5?mg/ml) and was not toxic to the normal Lep3 cells at lower concentration. Furthermore, the N-phosphonophenyl derivatives 1 and 2 displayed antiproliferative effect against mainly the MDA-MB-231 tumour cells at higher concentration.     

Antiproliferative activity of mixed-ligand dien-Cu(II) complexes with thiazole, thiazoline and imidazole derivatives.

The reaction of [Cu(dien)NO(3)]NO(3) with 2-amino-5-methylthiazole (2A5MT), 2-amino-2-thiazoline (2A-2Tzn), imidazole (im), N,N'-thiocarbonyldiimidazole (Tcdim), 2-aminothiazole (2AT) and 2-ethylimidazole (2Etim), gave a new series of mixed-ligand compounds of the general formula [Cu(dien)(B)NO(3))]NO(3); (dien, diethylenetriamine; B, 2A5MT, 2A-2Tzn, im, Tcdim, 2AT and 2Etim). The complexes have been characterised by elemental analysis, molar conductivity and magnetic measurements, as well as by electronic and IR spectral studies. According to the above measurements the possible structure of the compounds is the square pyramidal in the solid state and the square planar in aqueous solution. We tested all complexes for antiproliferative (cytostatic and cytotoxic) activity against a panel of cell lines (HeLa, L929, HT-29 and T47D). All [(dien)Cu(B)NO(3))](NO(3)) complexes had an activity against colon cancer cells (HT-29), inducing G2/M cell cycle arrest, an effect that for most of the complexes could be attributed to p34cdc2 inhibition by tyrosine-phosphorylation and/or to induction of (cyclin-dependent kinase inhibitor) p21(WAF1). Other cell lines were resistant to the majority of the complexes, except [Cu(dien)(2A5MT)NO(3))](NO(3)), that had showed the highest anti-proliferative activity against HT-29 cells also. The predilection for colon cancer cells and the relatively low toxicity against normal (L929) cells justify further investigation of this group of compounds.     

Triterpenoid Saponins with Potential Cytotoxic Activities from the Root Bark of Ilex rotunda Thunb.

A new 19‐oxo‐18,19‐seco‐ursane‐type triterpeonoid saponin, laevigin E ( 8 ), together with 17 known compounds ( 1 – 7 and 9 – 18 ) were isolated from the root bark of Ilex rotunda Thunb . Their structures were determined by various spectroscopic analysis. Among them, compounds 6 , 9 , 11 , and 18 were isolated from this species for the first time, while compounds 10 and 12 were firstly isolated from the family Aquifoliaceae. Biological activity assay showed that all triterpenoids exhibit moderate cytotoxic activities against MCF7, A549, HeLa and LN229 cell lines. The four triterpenoid saponins ( 3 , 4 , 6 , and 8 ) exhibit slightly better activities compared to the four triterpenoid sapogenins ( 1 , 2 , 5 , and 7 ). Compound 8 showed the best cytotoxicity against A549, HeLa and LN229 cell lines with IC₅₀ of 17.83, 22.58 and 30.98 μm , respectively.     

Benzothiazole thiourea derivatives as anticancer agents: Design,synthesis, and biological screening

In a systematic effort to identify a potent anticancer agent, we synthesized benzothiazole thiourea derivatives and examined their cytotoxic activity against five different human and animal cancer cell lines. Benzothiazolylthiocarbamides have been prepared in excellent yields by reaction of substituted 2-amino benzothiazoles with carbon disulfide and dimethyl sulfate followed by their ammonolysis. Cytotoxicity of the four compounds were screened for antitumor activity against human breast cancer cells (MCF-7), human cervix epithelial carcinoma (HeLa), human colon cancer cell line (HT-29), human leukemia cell line (K-562), and mouse neuroblastoma cell line (Neuro-2a) using cisplatin as a reference by MTT assay. Our results presented herein provide experimental evidence that benzothiazolylthiocarbamides induce apoptosis in cancer cell lines. According to flow cytometry results, treatment of HT-29 cells with 1-(6-ethoxy-1,3-benzothiazol- 2-yl)thiourea produced a large population of apoptotic cell (79.45%), which was 1.2-fold higher than that produced by cisplatin (65.28%) at the same concentration.     

Anti-proliferative potential of triphenyl substituted pyrimidines against MDA-MB-231, HCT-116 and HT-29 cancer cell lines

A series of triphenyl substituted pyrimidines as analogous of colchicine and combretastatin A-4 was synthesized and evaluated for the antiproliferative potential. The compounds were screened against MDA-MB-231, HCT-116 and HT-29 cell lines using MTT assay. Most of the compounds displayed antiproliferative activity in low to sub micro molar concentration. Amongst the synthesized derivatives, compounds HK-2, HK-10 and HK-13 were found to be effective against all the three cancer cell lines. HK-2 exhibited IC₅₀ values of 3.39 µM, 4.78 µM and 4.23 µM, HK-10 showed IC₅₀ values of 0.81 µM, 5.89 µM, 4.96 µM and HK-13 showed IC₅₀ values 3.24 µM, 4.93 µM and 4.73 µM against MDA-MB-231, HCT-116 and HT-29 cancer cell lines, respectively. HK-10 was found to be the most potent compound in the series with IC₅₀ values of 0.81 µM against MDA-MB-231. In the cell cycle analysis, HK-2 and HK-10 showed cell arrest at G2/M phase of the cell cycle while HK-13 inhibited cell growth at the G1/G0 phase. All the three compounds showed cell death induced through apoptosis. In the docking studies, HK-2, HK-10 and HK-13 were found to fit well in the colchicine binding site of the tubulin. Some of the compounds in the current series were found to be promising against all the three cancer cell lines and may act as potent leads for further development.     

Differential effects of type I IFN and IFN-gamma on the binding of tumor necrosis factor to receptors in two human cell lines

The effect of IFN-alpha and IFN-beta on the expression of cell surface receptors for tumor necrosis factor (TNF) was examined in two human cell lines. In HeLa cells, IFN-alpha and IFN-beta increased 125I-TNF binding, whereas in HT-29 cells these two IFN either slightly decreased or had no effect on 125I-TNF binding. In contrast, IFN-gamma increased 125I-TNF binding in both cell lines. Both IFN-alpha and IFN-beta exerted an antagonistic effect on IFN-gamma-induced stimulation of TNF receptor expression in HT-29 cells, but did not inhibit TNF receptor induction by IFN-gamma in HeLa cells. IFN-gamma and, to a lesser extent, IFN-beta were synergistic with TNF in producing cytotoxic/cytostatic activity in HT-29 cells. Despite the inhibitory effect of IFN-beta on the IFN-gamma-induced stimulation of TNF receptor expression, IFN-beta did not inhibit the synergistic enhancement of TNF cytotoxicity by IFN-gamma in HT-29 cells. The dissociation between the effects of IFN-beta on TNF receptor expression and on the cytotoxic activity of TNF in HT-29 cells suggests that TNF receptor modulation is not a major mechanism of synergism between IFN and TNF.     

Synthesis and antitumor evaluation of a novel series of triaminotriazine derivatives

A series of triaminotriazine derivatives (compounds 5a-f, 6a-x, and 7a-g) was designed, synthesized, and evaluated for their inhibition activities to colorectal cancer (CRC) cell lines (HCT-116 and HT-29). Most of the synthesized compounds demonstrated moderate anti-proliferatory effects on both HCT-116 and HT-29 cell lines at the concentration of 10 microM. The inhibitory activities against HCT-116 and HT-29 cell lines were discussed to develop the structure-activity relationships of this new series. Compounds 6l and 6o exhibited prominent inhibition activities toward HCT-116, with IC50s of 0.76 and 0.92 microM, respectively. The in vivo antitumor studies and pharmacokinetics of compound 6l showed that it might be a promising new hit for further development of antitumor agents.