Synthesis and biological evaluation of hydroxycinnamic acid hydrazide derivatives as inducer of caspase-3

Effect of nanovesicular surface-functionalization via chitosan and/or PEGylation on cytotoxicity of tamoxifen in induced-breast cancer model

AIMS

The effect of surface-modification of Tamoxifen (Tam)-loaded-niosomes on drug cytotoxicity and bio-distribution, via functionalization with chitosan and/or PEGylation, was investigated.

MATERIALS AND METHODS

Tam-loaded hybrid-nanocarriers (Tam-loaded niosomes, chitosomes, PEGylated niosomes, and PEGylated chitosomes) were formulated and characterized.

KEY FINDINGS

Chitosanization with/without PEGylation proved to selectively enhance Tam-release at the cancerous-acidic micromilieu. Cytotoxic activity study showed that Tam-loaded PEGylated niosomes had a lower IC₅₀ value on MCF-7 cell line (0.39, 0.35, and 0.27 times) than Tam-loaded PEGylated chitosomes, Tam-loaded niosomes, and Tam-loaded chitosomes, respectively. Cell cycle analysis showed that PEGylation and/or Chitosanization significantly impact Tam efficiency in inducing apoptosis, with a preferential influence of PEGylation over chitosanization. The assay of Annexin-V/PI double staining revealed that chitosanized-nanocarriers had a significant role in increasing the incidence of apoptosis over necrosis. Besides, PEGylated-nanocarriers increased apoptosis, as well as total death and necrosis percentages more than what was shown from free Tam. Moreover, the average changes in both Bax/Bcl-2 ratio and Caspase 9 were best improved in cells treated by Tam-loaded PEGylated niosomes over all other formulations. The in-vivo study involving DMBA-induced-breast cancer rats revealed that PEGylation made the highest tumor-growth inhibition (84.9 %) and breast tumor selectivity, while chitosanization had a lower accumulation tendency in the blood (62.3 ng/ml) and liver tissues (103.67 ng/ml). The histopathological specimens from the group treated with Tam-loaded PEGylated niosomes showed the best improvement over other formulations.

SIGNIFICANCE

All these results concluded the crucial effect of both PEGylation and chitosan-functionalization of Tam-loaded niosomes in enhancing effectiveness, targetability, and safety.

Efficient synthesis, biological evaluation, and docking study of isatin based derivatives as caspase inhibitors

In this paper, a new series of isatin-sulphonamide based derivatives were designed, synthesised and evaluated as caspase inhibitors. The compounds containing 1-(pyrrolidinyl)sulphonyl and 2-(phenoxymethyl)pyrrolidin-1-yl)sulphonyl substitution at C5 position of isatin core exhibited better results compared to unsubstituted derivatives. According to the results of caspase inhibitory activity, compound 20d showed moderate inhibitory activity against caspase-3 and −7 in vitro compared to Ac-DEVD-CHO (IC₅₀ = 0.016 ± 0.002 μM). Among the studied compounds, some active inhibitors with IC_50s in the range of 2.33–116.91 μM were identified. The activity of compound 20d was rationalised by the molecular modelling studies exhibiting the additional van der Waals interaction of N-phenylacetamide substitution along with efficacious T-shaped π-π and pi-cation interactions. The introduction of compound 20d with good caspase inhibitory activity will help researchers to find more potent agents.

An investigative study of antitumor properties of a novel thiazolo[4,5-d]pyrimidine small molecule revealing superior antitumor activity with CDK1 selectivity and potent pro-apoptotic properties

New thiazolo[4,5-d]pyrimidine analogues were synthesized and biologically assessed in-vitro for their antineoplastic activity. The growth inhibitory effects of these compounds were assessed through the National Cancer Institute-United States of America (NCI-USA) anticancer screening program. Compound5(7-Chloro-3-(2,4-dimethoxyphenyl)-5-methylthiazolo[4,5-d]pyrimidine-2(3H)-thione) was found to have a potent and broad-spectrum cytotoxic action against NCI panel with GI₅₀ (50% growth inhibition concentration) mean graph midpoint (MG-MID) = 2.88 µM. MTT assay was used to determine IC₅₀ values of the most potent agent against HCT-116 colorectal carcinoma and WI-38 human lung fibroblast cell lines; 5.33 µM ± 0.69 and 21.69 µM ± 1.04, respectively. Flow cytometric analysis revealed that compound5triggered apoptosis and G2/M cell cycle arrest. The ability of compound5to inhibit CDK1 (Cyclin-Dependent Kinase 1)/Cyclin B complex was evaluated, and its IC₅₀ value was 97 nM ± 2.33. Moreover, according to the gene expression analysis, compound5up-regulated p53, BAX, cytochrome c, caspases-3,-8 and-9 besides down-regulated Bcl-2. In conclusion, compound5exerted a potent pro-apoptotic activity through the activation of the intrinsic apoptotic pathway and arrested the cell cycle at the G2/M phase.

Dietary Phenolic Acids and Flavonoids as Potential Anti-Cancer Agents: Current State of the Art and Future Perspectives

Background:

Cancer is a rapidly growing disease and the second most leading cause of death worldwide. Breast, colon, lung, and prostate cancer are the most diagnosed types of cancer among the majority of the population. The prevalence of these cancers is increasing rapidly due to the lack of effective drugs. The search for anti-cancer bioactive components from natural plant sources is gaining immense significance. The aim of the paper is to introduce the readers about the in vitro and in vivo biochemical mechanisms of phenolic acids and flavonoids in these four types of cancers.

Methods:

A literature search was carried out in databases, including Scopus, SciFinder, Springer, Science direct and Google. The main keywords used were fruits & vegetables, phenolic acids, flavonoids, anticancer, bioavailability, etc. The data obtained were integrated and analyzed.

Results:

The study revealed the potential molecular mechanisms of phenolic acids and flavonoids, which include the induction of apoptosis, inhibition of cell proliferation, cell-cycle arrest, induction of Poly ADP ribose polymerase cleavage, downregulation of Matrix metalloproteinases-2 and Matrix metalloproteinases-9 activities, decreased levels of B-cell lymphoma-2, etc. Promising effects of phenolic acids and flavonoids have been observed against breast, colon, lung and prostate cancers.

Conclusion:

The in vitro and in vivo anti-cancer mechanisms of phenolic acids and flavonoids have been revealed in this study. With the knowledge of specific molecular targets and the structural-functional relationship of bioactive compounds, the current review will open a new gateway for the scientific community and provide them a viable option to exploit more of these compounds for the development of novel and efficacious anticancer compounds.

One-Pot Synthesis of Novel Thiazoles as Potential Anti-Cancer Agents

Background

Thiazole and thiosemicarbazone derivatives are known to have potential anticancer activity with a mechanism of action related to inhibition of matrix metallo-proteinases, kinases and anti-apoptotic BCL2 family proteins.

Materials and Methods

A novel three series of 5-(1-(2-(thiazol-2-yl)hydrazono)ethyl)thiazole derivatives were prepared in a one-pot three-component reaction using 2-(2-benzylidene hydrazinyl)-4-methylthiazole as a starting precursor. MS, IR, ¹H-NMR and ¹³C-NMR were used to elucidate the structures of the synthesized compounds. Most of the synthesized products were evaluated for their in vitro anticancer screening against HCT-116, HT-29 and HepG2 using the MTT colorimetric assay.

Results

The results indicated that compounds 4c, 4d and 8c showed growth inhibition activity against HCT-116 with IC₅₀ values of 3.80 ± 0.80, 3.65 ± 0.90 and 3.16 ± 0.90 μM, respectively, compared to harmine (IC₅₀ = 2.40 ± 0.12 μM) and cisplatin (IC₅₀ = 5.18 ± 0.94 μM) reference drugs. Also, compounds 8c, 4d and 4c showed promising IC₅₀ values of 3.47 ± 0.79, 4.13 ± 0.51 and 7.24 ± 0.62 μM, respectively, against the more resistant human colorectal cancer (HT-29) cell line compared with harmine (IC₅₀ = 4.59 ± 0.67 μM) and cisplatin (IC₅₀ = 11.68 ± 1.54 μM). On the other hand, compounds 4d, 4c, 8c and 11c were the most active (IC₅₀ values of 2.31± 0.43, 2.94 ± 0.62, 4.57 ± 0.85 and 9.86 ± 0.78 μM, respectively) against the hepatocellular carcinoma (HepG2) cell line compared with harmine (IC₅₀ = 2.54 ± 0.82 μM) and cisplatin (IC₅₀ = 41 ± 0.63 μM). The study also suggested that the mechanism of the anticancer action exerted by the most active compounds (4c, 4d and 8c) inside HCT-116 cells was apoptosis through the Bcl-2 family.

Conclusion

Thiazole scaffolds 4c, 4d and 8c showed anticancer activities in the micromolar range and are appropriate as a candidate for cancer treatment.

Design, Synthesis of N-phenethyl Cinnamide Derivatives and Their Biological Activities for the Treatment of Alzheimer's Disease: Antioxidant, Beta-amyloid Disaggregating and Rescue Effects on Memory Loss

Gx-50 is a bioactive compound for the treatment of Alzheimer’s disease (AD) found in Sichuan pepper (Zanthoxylum bungeanum). In order to find a stronger anti-AD lead compound, 20 gx-50 (1–20) analogs have been designed and synthesized, and their molecular structures were determined based on nuclear magnetic resonance (NMR) and mass spectrometry (MS) analysis, as well as comparison with literature data. Compounds 1–20 were evaluated for their anti-AD potential by using DPPH radical scavenging assay for considering their anti-oxidant activity, thioflavin T (ThT) fluorescence assay for considering the inhibitory or disaggregate potency of Aβ, and transgenic Drosophila model assay for evaluating their rescue effect on memory loss. Finally, compound 13 was determined as a promising anti-AD candidate.

Novel [(3-indolylmethylene)hydrazono]indolin-2-ones as apoptotic anti-proliferative agents: design, synthesis and in vitro biological evaluation

On account of their significance as apoptosis inducing agents, merging indole and 3-hydrazinoindolin-2-one scaffolds is a logic tactic for designing pro-apoptotic agents. Consequently, 27 hybrids (6a–r, 9a–f and 11a–c) were synthesised and evaluated for their cytotoxicity against MCF-7, HepG-2 and HCT-116 cancer cell lines. SAR studies unravelled that N-propylindole derivatives were the most active compounds such as 6n (MCF-7; IC₅₀=1.04 µM), which displayed a significant decrease of cell population in the G2/M phase and significant increase in the early and late apoptosis by 19-folds in Annexin-V-FTIC assay. Also, 6n increased the expression of caspase-3, caspase-9, cytochrome C and Bax and decreased the expression of Bcl-2. Moreover, compounds 6i, 6j, 6n and 6q generated ROS by significant increase in the level of SOD and depletion of the levels of CAT and GSH-Px in MCF-7.

Synthesis of pyrazole acrylic acid based oxadiazole and amide derivatives as antimalarial and anticancer agents

Depravity of malaria in terms of morbidity and mortality in human beings makes it a major health issue in tropical and subtropical areas of the globe. Drug counterfeiting and non-adherence to the treatment regimen have significantly contributed to development and spread of multidrug resistance that has highlighted the need for development of novel and more efficient antimalarial drugs. Complexity associated with cancer disease and prevalence of diversified cell populations vindicates highly specific treatment options for treatment of cancer. Resistance to these anticancer agents has posed a great hindrance in successful treatment of cancer. Pondering this ongoing situation, it was speculated to develop novel compounds targeting malaria and cancer. Moving on the same aisle, we synthesized pyrazole acrylic acid based oxadiazole and amide derivatives using multi-step reaction pathways (6a-x; 6a'-h'). Schizont maturation inhibition assay was employed to determine antimalarial potential. Compound 6v emerged as the most potent antimalarial agent targeting falcipain-2 enzyme. Anticancer activity was done using sulforhodamine B assay. Compounds 6b' and 6g' demonstrated promising results against all the tested cell lines. Further, Microscopic view clearly indicated formation of apoptotic bodies, chromatin condensation, shrinkage of cells and bleb formation. Validation of the results was achieved using molecular docking studies. From the obtained results, it was observed that cyclization (oxadiazole) favored antimalarial activity while non-cyclized compounds (amides) emerged as better anticancer agents.

Long Chain Alkyl Esters of Hydroxycinnamic Acids as Promising Anticancer Agents: Selective Induction of Apoptosis in Cancer Cells

Cancer is the major cause of morbidity and mortality worldwide. Hydroxycinnamic acids (HCAs) are naturally occurring compounds and their alkyl esters may possess enhanced biological activities. We evaluated C4, C14, C16, and C18 alkyl esters of p-coumaric, ferulic, sinapic, and caffeic acids (19 compounds) for their cytotoxic activity against four human cancer cells and also examined their effect on cell cycle alteration and apoptosis induction. The tetradecyl (1c) and hexadecyl (1d) esters of p-coumaric acid and tetradecyl ester of caffeic acid (4c), but not the parental HCAs, were selectively effective against MOLT-4 (human lymphoblastic leukemia) cells with IC₅₀ values of 0.123 ± 0.012, 0.301 ± 0.069 and 1.0 ± 0.1 μM, respectively. Compounds 1c, 1d, and 4c significantly increased apoptotic cells in sub-G1 phase and activated the caspase-3 enzyme in MOLT-4 cells. Compound 1c was 15.4 and 23.6 times more potent than doxorubicin and cisplatin, respectively, against the drug resistant MES-SA-DX5 uterine sarcoma cells. These p-coumarate esters were several times less effective against NIH/3T3 fibroblast cells. Docking studies showed that 1c may cause cytotoxicity by interaction with carbonic anhydrase IX. In conclusion, long chain alkyl esters of p-coumaric acid are promising scaffolds for selective apoptosis induction in cancer cells.

Analogue based drug design, synthesis, molecular docking and anticancer evaluation of novel chromene sulfonamide hybrids as aromatase inhibitors and apoptosis enhancers

Twenty novel chromene derivatives carrying different sulfonamide moieties (3-22) were designed and synthesized. All the newly prepared compounds were evaluated for their in vitro anticancer activity against breast cancer cell line (T47D). Most of the synthesized compounds showed good to moderate activity (IC₅₀ = 8.8-108.9 μM), where compound 16 (IC₅₀ = 8.8 μM) exhibited higher activity compared to doxorubicin (IC₅₀ = 9.8 μM). In order to determine the mechanism of the anticancer activity in T47D cells, the effect of the most potent compounds (5-8, 11-14, and 16-18) on the aromatase activity was tested. Most of the selected compounds showed significant inhibitory effect on the aromatase activity, with compound 18 showing IC₅₀ = 4.66 μM. Furthermore, apoptosis studies were conducted on two of the most potent compounds (8 & 16) to estimate the proapoptotic potential of our compounds. Both induced the levels of active caspase 3, caspase 8 and caspase 9. Moreover, they surprisingly boosted the Bax/Bcl2 ratio 5936 & 33,000 folds, respectively compared to the control. Moreover, they showed mild cytotoxic effect (IC₅₀ = 183.8 μM & 172.04 μM, respectively) in normal breast cells 184A1. Finally, a molecular docking study was performed to investigate the probable interaction with the aromatase enzyme.