LYG-202, a new flavonoid with a piperazine substitution, shows antitumor effects in vivo and in vitro

Novel Synthesized N-Ethyl-Piperazinyl-Amides of C2-Substituted Oleanonic and Ursonic Acids Exhibit Cytotoxic Effects through Apoptotic Cell Death Regulation

A series of novel hybrid chalcone N-ethyl-piperazinyl amide derivatives of oleanonic and ursonic acids were synthesized, and their cytotoxic potential was evaluated in vitro against the NCI-60 cancer cell line panel. Compounds 4 and 6 exhibited the highest overall anticancer activity, with GI₅₀ values in some cases reaching nanomolar values. Thus, the two compounds were further assessed in detail in order to identify a possible apoptosis- and antiangiogenic-based mechanism of action induced by the assessed compounds. DAPI staining revealed that both compounds induced nuclei condensation and overall cell morphological changes consistent with apoptotic cell death. rtPCR analysis showed that up-regulation of pro-apoptotic Bak gene combined with the down-regulation of the pro-survival Bcl-XL and Bcl-2 genes caused altered ratios between the pro-apoptotic and anti-apoptotic proteins’ levels, leading to overall induced apoptosis. Molecular docking analysis revealed that both compounds exhibited high scores for Bcl-XL inhibition, suggesting that compounds may induce apoptotic cell death through targeted anti-apoptotic protein inhibition, as well. Ex vivo determinations showed that both compounds did not significantly alter the angiogenesis process on the tested cell lines.

In Vitro Antitumor Activities of Biologically Active Extracts and Isolated Phytochemicals From Rabdosia latifolia C. Y. Wu Et H. W. Li in Addenda

To investigate the antitumor activities, as well as phytochemical constituents of Rabdosia latifolia C. Y. Wu et H. W. Li in Addenda ( R. latifolia) extracts, the light petroleum, dichloromethane, ethyl acetate, n-butanol, and water extracts from R. latifolia were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays on MCF-7, HepG2, A549, Hela, and BGC-823 cells. We further examined cell cycle and apoptosis of the biologically active extracts on MCF-7 cells. The constituents of the biologically active extracts were determined using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Triple-TOF/MS) and gas chromatography–mass spectrometric (GC–MS) analysis. MTT assays showed that the dichloromethane extract had an inhibitory effect on MCF-7 and BGC-823 cells and that at 50 µg/mL showed 9.9% ± 1.7% inhibition of MCF-7 cells and 81.7% ± 9.5% of BGC-823 cells, respectively. The data for cell cycle analysis clearly showed a significant block in the S-phase. The dichloromethane extract induced apoptosis of MCF-7 cells, and the cell apoptosis rate showed time and concentration effects. UPLC- Triple-TOF/MS analysis revealed the presence of 16 structurally characterized compounds in the dichloromethane extract, all of which were identified for the first time in this species. Ent-kauranoids, such as henryin (9) and its analogs, were the predominant compounds. Subsequently, GC–MS analysis showed the presence of 20 volatile compounds, including γ-sitostenone, β-amyrone, γ-tocopherol, and dotriacontane. Based on the results of this study and previous literature reports, it is concluded that the ent-kauranoids, such as henryin, were the predominant components of R. latifolia with antitumor activity.

Identifying new piperazine-based PARP1 inhibitors using text mining and integrated molecular modeling approaches

One of the important molecular targets for antitumor drug discovery is the polyadenosine diphosphate-ribose polymerase-1 (PARP1) enzyme. It is linked with various biological functions including DNA repair and apoptosis. It is primarily a nuclear enzyme linked to chromatin, which is activated by DNA damage. Improved expression of PARP1 in melanomas, breast cancer, lung cancer and other neoplastic diseases is often observed. A tremendous PARP research concerning cancer and ischemia is progressing very rapidly. There are currently four PARP1 inhibitors approved by the FDA on the market, namely Olaparib, Rucaparib, Niraparib and Talazoparib. All of these molecules are non-selective inhibitors of PARP1. Currently there is an urgent need for novel and selective PARP1 inhibitors. In this work, asmall molecule database (Specs SC) were used to identify the new selective lead inhibitors of PARP1. Piperazine scaffold is an important fragment that is used in many currently used FDA approved drugs in different diseases including PARP1 inhibitor Olaparib. Thus, based on text mining studies, 4674 compounds thatinclude piperazine fragments were identified and virtually screened at the binding pocket of target protein PARP1. Compounds that have high docking scores were used in molecular dynamics (MD) simulations. Free energy calculations were also performed to compare the predicted binding energies with known PARP1 inhibitors. The critical amino acid interactions of these newly identified hits in the binding pocket were also investigated in detail for better understanding of the structural features required for next generation PARP1 inhibitors. Thus, here together with combination of text-mining and integrated molecular modeling approaches, we identified novel piperazine-based hits against PARP1 enzyme.Communicated by Ramaswamy H. Sarma.

Novel Carbazole-Piperazine Hybrid Small Molecule Induces Apoptosis by Targeting BCL-2 and Inhibits Tumor Progression in Lung Adenocarcinoma in Vitro and Xenograft Mice Model

Lung cancer is a type of deadly cancer and a leading cause of cancer associated death worldwide. BCL-2 protein is considered as an imperative target for the treatment of cancer due to their significant involvement in cell survival and death. A carbazole-piperazine hybrid molecule ECPU-0001 was designed and synthesized as a potent BCL-2 targeting agent with effective anticancer cancer activity. Interaction of ECPU-001 has been assessed by docking, molecular dynamics (MD) simulation, and thermal shift assay. Further, in vitro and in vivo anticancer activity was executed by cytotoxicity assay, FACS, colony formation and migration assay, western blotting, immunocyto/histochemistry and xenograft nude mice model. Molecular docking and MD simulation study confirmed that ECPU-0001 nicely interacts with the active site of BCL-2 by displaying a Ki value of 5.72 µM and binding energy (ΔG) of -8.35 kcal/mol. Thermal shift assay also validated strong interaction of this compound with BCL-2. ECPU-0001 effectively exerted a cytotoxic effect against lung adenocarnoma cells A459 with an IC50 value of 1.779 µM. Molecular mechanism of action have also been investigated and found that ECPU-0001 induced apoptosis in A459 cell by targeting BCL-2 to induce intrinsic pathway of apoptosis. Administration of ECPU-0001 significantly inhibited progression of tumor in a xenograft model without exerting severe toxicity and remarkably reduced tumor volume as well as tumor burden in treated animals. Our investigation bestowed ECPU-0001 as an effective tumoricidal agent which exhibited impressive anticancer activity in vitro as well as in vivo by targeting BCL-2 associated intrinsic pathway of apoptosis. Thus, ECPU-0001 may provide a valuable input for therapy of lung adenosarcoma in future, however, further extensive investigation of this compound will be needed.

An Investigation on Glucuronidation Metabolite Identification, Isozyme Contribution, and Species Differences of GL-V9 In Vitro and In Vivo

GL-V9 is a prominent derivative of wogonin with a wide therapeutic spectrum and potent anti-tumor activity. The metabolism characteristics of GL-V9 remain unclear. This study aimed to clarify the metabolic pathway of GL-V9 and investigate the generation of its glucuronidation metabolites in vitro and in vivo. HPLC-UV-TripleTOF was used to identify metabolites. The main metabolite that we found was chemically synthesized and the synthetic metabolite was utilized as standard substance for the subsequent metabolism studies of GL-V9, including enzyme kinetics in liver microsomes of five different species and reaction phenotyping metabolism using 12 recombinant human UDP-glucuronosyltransferase (UGT) isoforms. Results indicated that the glucuronidation reaction occurred at C5-OH group, and 5-O-glucuronide GL-V9 is the only glucuronide metabolite and major phase II metabolite of GL-V9. Among 12 recombinant human UGTs, rUGT1A9 showed the strongest catalytic capacity for the glucuronidation reaction of GL-V9. rUGT1A7 and rUGT1A8 were also involved in the glucuronidation metabolism. Km of rUGT1A7-1A9 was 3.25 ± 0.29, 13.92 ± 1.05, and 4.72 ± 0.28 μM, respectively. In conclusion, 5-O-glucuronide GL-V9 is the dominant phase II metabolite of GL-V9 in vivo and in vitro, whose formation rate and efficiency are closely related to isoform-specific metabolism profiles and the distribution of UGTs in different tissues of different species.

LYG-202 inhibits activation of endothelial cells and angiogenesis through CXCL12/CXCR7 pathway in breast cancer

Angiogenesis is critical for the growth and metastasis of triple-negative breast cancer (TNBC) and its inhibition reduces the risk of progression of metastatic TNBC. In this study, we investigated that LYG-202, a flavonoid with a piperazine substitution, inhibited angiogenesis induced by conditioned media (CM) from MDA-MB-231 cells under hypoxia and revealed its underlying mechanism. The results showed that LYG-202 decreased CXCL12 secretion and CXCR7 expression, leading to suppression of its downstream ERK/AKT/nuclear factor kappa B (NF-κB) signaling, which eventually decreased the expression of MMP-2, MMP-9, RhoA and increased VE-cadherin expression in EA.hy 926 cells treated with CM from MDA-MB-231 cells under hypoxia. The decreased migration ability, increased cell adhesion and inhibited CXCR7 pathway by LYG-202 could also be reproduced in human umbilical vein endothelial cells. More importantly, LYG-202 also inhibited tumor angiogenesis and tumor growth of human breast cancer MDA-MB-231 cells in nude mice through CXCL12/CXCR7 pathway. In summary, LYG-202 is a potential agent to prohibit tumor angiogenesis through inhibiting the activation of endothelial cells.

Screening Effects of Methanol Extracts of Diplotaxis tenuifolia and Reseda lutea on Enzymatic Antioxidant Defense Systems and Aldose Reductase Activity

OBJECTIVES

The aim of the study was to investigate the effects of methanol extracts from the flowers and leaves of Diplotaxis tenuifolia and Reseda lutea on the activity of AR, CAT, GST, and GPx.

MATERIALS AND METHODS

Total phenolic and flavonoid contents of the plant samples were evaluated using Folin-Ciocalteu reagent and aluminum chloride colorimetric methods. Also, the effects of extracts on CAT, GST, GPx, and AR enzyme activities were investigated using kinetic assays.

RESULTS

The highest phenolic and flavonoid contents were detected in the methanol extract of D. tenuifolia leaves with 144.49±0.29 mg gallic acid equivalent/L and 250.485±0.002 quercetin equivalent/L, respectively. The best activity profile for GST and GPx were observed in the extract of leaves belonging to D. tenuifolia with IC₅₀ values of 121±0.05 and 140±0.001 ng/mL, respectively. According to the results, methanol extracts from leaves of R. lutea and D. tenuifolia showed no significant activity potential on AR. Moreover, none of the studied extracts demonstrated any reasonable CAT activation potential.

CONCLUSION

The results indicated that leaves of D. tenuifolia had good effect on the antioxidant enzymatic defense system, which it makes it a good constituent of the daily diet.

Design, synthesis, and evaluation of novel ursolic acid derivatives as HIF-1α inhibitors with anticancer potential

Hypoxia-inducible factor-1α (HIF-1α), a key mediator in tumor metastasis and angiogenesis, is associated with poor patient prognosis and has been recognized as an important cancer drug target. In this work, four novel series of ursolic acid derivatives containing oxadiazole, triazolone, and piperazine moieties were designed, synthesized, and evaluated for anti-tumor activity as HIF-1α inhibitors. The majority of the compounds showed an excellent ability to inhibit the expression of HIF-1α. In particular, 11b inhibited HIF-1α transcriptional activity under hypoxic conditions with IC50=36.9μM. The cytotoxicity of these compounds was also assessed in human colon cancer cell HCT116 cells by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and no compounds showed any appreciable cytotoxic activity (IC50>100μmol/L), which was lower than that of ursolic acid (IC50=23.8μmol/L). The mechanism of action of the representative compound 11b was also investigated.

Exploiting Cell Death Pathways for Inducible Cell Elimination to Modulate Graft-versus-Host-Disease

Hematopoietic stem cell transplantation is a potent form of immunotherapy, potentially life-saving for many malignant hematologic diseases. However, donor lymphocytes infused with the graft while exerting a graft versus malignancy effect can also cause potentially fatal graft versus host disease (GVHD). Our group has previously validated the inducible caspase-9 suicide gene in the haploidentical stem cell transplant setting, which proved successful in reversing signs and symptoms of GVHD within hours, using a non-therapeutic dimerizing agent. Cellular death pathways such as apoptosis and necroptosis are important processes in maintaining healthy cellular homeostasis within the human body. Here, we review two of the most widely investigated cell death pathways active in T-cells (apoptosis and necroptosis), as well as the emerging strategies that can be exploited for the safety of T-cell therapies. Furthermore, such strategies could be exploited for the safety of other cellular therapeutics as well.

Novel Triazole-Piperazine Hybrid Molecules Induce Apoptosis via Activation of the Mitochondrial Pathway and Exhibit Antitumor Efficacy in Osteosarcoma Xenograft Nude Mice Model

Mitochondria impart a crucial role in the regulation of programmed cell death and reactive oxygen species (ROS) generation, besides serving as a primary energy source. Mitochondria appeared as an important target for the therapy of cancer due to their significant contribution to cell survival and death. Here, we report the design and synthesis of a novel series of triazole-piperazine hybrids as potent anticancer agents. MCS-5 emerged as an excellent anticancer agent which showed better anticancer activity than the standard drug doxorubicin in in vitro and in vivo studies. MCS-5 displayed an IC₅₀ value of 1.92 μM and induced apoptosis in Cal72 (human osteosarcoma cell line) cells by targeting the mitochondrial pathway. This compound arrested the G2/M phase of the cell cycle and induced ROS production and mitochondrial potential collapse in Cal72 cells. MCS-5 displayed excellent anticancer activity in the Cal72 xenograft nude mice model, where it significantly reduced tumor progression, leading to enhanced life span in treated animals compared to control and doxorubicin treated animals without exerting noticeable toxicity. In addition, a 2DG optical probe guided study clearly evoked that MCS-5 remarkably reduced tumor metastasis in the Cal72 xenograft nude mice model. These results indicate that MCS-5 appeared as a novel chemical entity which is endowed with excellent in vitro as well as in vivo anticancer activity and may contribute significantly to the management of cancer in the future.

LYG-202 exerts antitumor effect on PI3K/Akt signaling pathway in human breast cancer cells

In this study, we aimed to investigate the antitumor effect of LYG-202, a newly synthesized piperazine-substituted derivative of flavonoid on human breast cancer cells and illustrate the potential mechanisms. LYG-202 induced apoptosis in MCF-7, MDA-MB-231 and MDA-MB-435 cells. LYG-202 triggered the activation of mitochondrial apoptotic pathway through multiple steps: increasing Bax/Bcl-2 ratio, decreasing mitochondrial membrane potential (ΔΨ(m)), activating caspase-9 and caspase-3, inducing cleavage of poly(ADP-ribose) polymerase, cytochrome c release and apoptosis-inducing factor translocation. Furthermore, LYG-202 inhibited cell cycle progression at the G1/S transition via targeting Cyclin D, CDK4 and p21(Waf1/Cip1). Additionally, LYG-202 increased the generation of intracellular ROS. N-Acetyl cysteine, an antioxidant, reversed LYG-202-induced apoptosis suggesting that LYG-202 induces apoptosis by accelerating ROS generation. Further, we found that LYG-202 deactivated the PI3K/Akt pathway, activated Bad phosphorylation, increased Cyclin D and Bcl-xL expression, and inhibited NF-κB nuclear translocation. Activation of PI3K/Akt pathway by IGF-1 attenuated LYG-202-induced apoptosis and cell cycle arrest. Our in vivo study showed that LYG-202 exhibited a potential antitumor effect in nude mice inoculated with MCF-7 tumor through similar mechanisms identified in cultured cells. In summary, our results demonstrated that LYG-202 induced apoptosis and cell cycle arrest via targeting PI3K/Akt pathway, indicating that LYG-202 is a potential anticancer agent for breast cancer.

Synthesis and antitumor activities of piperazine- and cyclen-conjugated dehydroabietylamine derivatives

A series of piperazine- and cyclen-conjugated dehydroabietylamine derivatives were synthesized and characterized by 1H NMR, 13C NMR, and HRMS. The in vitro antitumor activities of conjugates 10–13 against MCF-7 and HepG-2 tumor cell lines were evaluated using CCK-8 assay. The results show that the synthesized compounds cause a dose-dependent inhibition of cell proliferation and display different antitumor activities with the IC50 values ranging from 23.56 to 78.92 μm. Moreover, the antitumor activity of conjugate 10 against the MCF-7 cell line is superior to that of the positive control 5-fluorouracil. In addition, flow cytometric assay revealed that the representative conjugate 10 could induce apoptosis in MCF-7 tumor cells in a dose-dependent manner.

Piperazine scaffold: A remarkable tool in generation of diverse pharmacological agents

Piperazine is one of the most sought heterocyclics for the development of new drug candidates. This ring can be traced in a number of well established, commercially available drugs. Wide array of pharmacological activities exhibited by piperazine derivatives have made them indispensable anchors for the development of novel therapeutic agents. The review herein highlights the therapeutic significance of piperazine derivatives. Various therapeutically active piperazine derivatives developed by several chemists are reported here.

LZ-207, a Newly Synthesized Flavonoid, Induces Apoptosis and Suppresses Inflammation-Related Colon Cancer by Inhibiting the NF-κB Signaling Pathway

Flavonoids and flavonoid derivatives, which have significant biological and pharmacological activities, including antitumor and anti-inflammatory activities, have been widely used in human healthcare. To design a more effective flavonoid antitumor agent, we altered the flavonoid backbone with substitutions of piperazine and methoxy groups to synthesize a novel flavonoid derivative, LZ-207. The anticancer effect of LZ-207 against HCT116 colon cancer cells and the underlying mechanism of this effect were explored in this study. Specifically, LZ-207 exhibited inhibitory effects on growth and viability in several human colon cancer cell lines and induced apoptosis in HCT116 cells both in vitro and in vivo. LZ-207 treatment also suppressed the nuclear translocation of NF-κB and the phosphorylation of IκB and IKKα/β in a dose-dependent manner in both HCT116 cells and human acute monocytic leukemia THP-1 cells. Moreover, LZ-207 also reduced the secretion of the pro-inflammatory cytokine interleukin-6 (IL-6) in LPS-induced THP-1 cells, and this effect was confirmed at the transcriptional level. Furthermore, LZ-207 significantly inhibited HCT116 cell proliferation that was elicited by LPS-induced THP-1 cells in a co-culture system. These findings elucidated some potential molecular mechanisms for preventing inflammation-driven colon cancer using the newly synthesized flavonoid LZ-207 and suggested the possibility of further developing novel therapeutic agents derived from flavonoids.

Synthesis and X-ray Structure Characterisation of Novel Pyrazole Carboxamide Derivatives

A series of novel pyrazole carboxamide derivatives containing piperazine moiety was synthesised and determined by IR, 1H NMR and HRMS spectroscopy. Especially, the structure was confirmed by the X-ray crystal analysis of [1-(4- tert-butylbenzyl)-4-chloro-3-(4-chlorophenyl)-1 H-pyrazol-5-yl](4-phenylpiperazin-1-yl)methanone.

Synthesis and cytotoxicity of novel ursolic acid derivatives containing an acyl piperazine moiety

This study designed and synthesized a series of novel ursolic acid derivatives in an attempt to develop potent antitumor agents. Their structures were confirmed using MS, IR, (1)H NMR and (13)C NMR. The inhibitory activities of the title compounds against the MGC-803 (gastric cancer cell) and Bcap-37 (breast cancer cell) human cancer cell lines were evaluated using standard MTT assay in vitro. The pharmacological results showed that some of the compounds displayed moderate to high levels of antitumor activities against the tested cancer cell lines and that most exhibited more potent inhibitory activities compared with ursolic acid. The mechanism of compound 4b was preliminarily investigated by acridine orange/ethidium bromide staining, Hoechst 33258 staining, TUNEL assay and flow cytometry, which revealed that the compound can induce cell apoptosis in MGC-803 cells.

Extracts of Lycoris aurea induce apoptosis in murine sarcoma S180 cells

Lycoris species have been known since long ago as a multi-utility ethnomedicinal herbal in China. It has been reported to exhibit a number of properties such as anticancer, neuroprotective, and antibacterial activities. In the present study, the anticancer efficacy of dichloromethane extracts of Lycoris aurea (DELA), was evaluated both in vivo and in vitro using murine sarcoma 180 cells. To evaluate the effects of DELA on apoptotic cell death, flow cytometry and Western blotting were performed. DELA demonstrated promising inhibition effects on sarcoma 180 cells in vitro and a 53.49% inhibitory rate on cancer cells in vivo. DELA treatment increased thymus indices and spleen indices in vivo, indicating that it reduced tumours, but did not damage the main immune organs. The DELA-evoked increase in apoptotic cell death was accompanied by occurrence of cleaved caspase-3 and decreases in the ratio of Bcl-2/Bax. Further purification and LCMS analysis showed DELA contained homolycorine, 2α-hydroxyoduline, oduline, hippeastrine, 2α-hydroxy-6-O- methyloduline, and 2α-methoxy-6-O-methyloduline. These results indicate that DELA exerted its anticancer effects, at least in part, by inducing cancer cell apoptosis and thus can be considered as a potential candidate agent for treatment of cancer.

LYG-202 inhibits the proliferation of human colorectal carcinoma HCT-116 cells through induction of G1/S cell cycle arrest and apoptosis via p53 and p21(WAF1/Cip1) expression

We recently established that LYG-202, a new flavonoid with a piperazine substitution, exerts an anti-tumor effect in vivo and in vitro. In the present study, we demonstrate that LYG-202 induces G1/S phase arrest and apoptosis in human colorectal carcinoma HCT-116 cells. Data showed that the blockade of the cell cycle was associated with increased p21(WAF1/Cip1) and Rb levels and reduced expression of cyclin D1, cyclin E, and CDK4. Moreover, PARP cleavage, activation of caspase-3, caspase-8, and caspase-9, and an increased ratio of Bax/Bcl-2 were detected in LYG-202-induced apoptosis. Additionally, activation of p53 resulted in the up-regulation of its downstream targets PUMA and p21(WAF1/Cip1), as well as the down-regulation of its negative regulator MDM2, suggesting that the p53 pathway may play a crucial role in LYG-202-induced cell cycle arrest and apoptosis. Furthermore, siRNA knockdown of p53 attenuated the G1 cell cycle arrest and apoptosis induced by LYG-202, as the effects of LYG-202 on up-regulation of p21(WAF1/Cip1) and down-regulation of Bcl-2 and pro-caspase-3 were partly inhibited in p53 siRNA transfected cells compared with control siRNA transfected cells. Collectively, these data indicate that LYG-202 exerts its anti-tumor potency by activating the p53-p21 pathway for G1/S cell cycle arrest and apoptosis in colorectal cancer cells.

Reactive oxygen species-mitochondria pathway involved in LYG-202-induced apoptosis in human hepatocellular carcinoma HepG(2) cells

Previously, we demonstrated that LYG-202, a newly synthesized flavonoid with a piperazine substitution, exhibited obvious antitumor activity in vivo and in vitro. The exact mechanism of this new compound remains unclear. In the present study, we examined the effects of LYG-202 on reactive oxygen species (ROS) production and the downstream signaling pathway in the apoptosis of human hepatocellular carcinoma HepG(2) cells. Pretreatment with NAC (N-acetylcysteine), a ROS production inhibitor, partly inhibited the apoptosis induced by LYG-202 via blocking the ROS generation. Further data revealed that LYG-202 induced ROS accumulation followed by a decrease in mitochondrial membrane potential (MMP), release of cytochrome c (Cyt c) and apoptosis-inducing factor (AIF) to cytosol, which induced apoptosis of the cells. Moreover, the mitogen-activated protein kinases (MAPK), the downstream effect of ROS accumulation including c-Jun N-terminal kinase (JNK) and p38 MAPK, could be activated by LYG-202. Taken together, the generation of ROS might play an important role in LYG-202-induced mitochondrial apoptosis pathway, which provided further support for LYG-202 as a novel anticancer therapeutic candidate.