Overexpression of caspase-3 in hepatocellular carcinomas

Design, synthesis, molecular modelling and biological evaluation of novel 6-amino-5-cyano-2-thiopyrimidine derivatives as potent anticancer agents against leukemia and apoptotic inducers

Herein, a novel series of 6-amino-5-cyano-2-thiopyrimidines and condensed pyrimidines analogues were prepared. All the synthesized compounds (1a-c, 2a-c, 3a-c, 4a-r and 5a-c) were evaluated for in vitro anticancer activity by the National Cancer Institute (NCI; MD, USA) against 60 cell lines. Compound 1c showed promising anticancer activity and was selected for the five-dose testing. Results demonstrated that compound 1c possessed broad spectrum anti-cancer activity against the nine cancerous subpanels tested with selectivity ratio ranging from 0.7 to 39 at the GI50 level with high selectivity towards leukaemia. Mechanistic studies showed that Compound 1c showed comparable activity to Duvelisib against PI3Kδ (IC50 = 0.0034 and 0.0025 μM, respectively) and arrested cell cycle at the S phase and displayed significant increase in the early and late apoptosis in HL60 and leukaemia SR cells. The necrosis percentage showed a significant increase from 1.13% to 3.41% in compound 1c treated HL60 cells as well as from 1.51% to 4.72% in compound 1c treated leukaemia SR cells. Also, compound 1c triggered apoptosis by activating caspase 3, Bax, P53 and suppressing Bcl2. Moreover, 1c revealed a good safety profile against human normal lung fibroblast cell line (WI-38 cells). Molecular analysis of Duvelisib and compound 1c in PI3K was performed. Finally, these results suggest that 2-thiopyrimidine derivative 1c might serve as a model for designing novel anticancer drugs in the future.

In silico analysis of the interaction of de novo peptides derived from Salvia hispanica with anticancer targetsEvaluation of the anticancer potential of de novo peptides derived from Salvia hispanica through molecular docking

Cancer is one of the leading causes of death worldwide. Conventional cancer therapies are not selective to cancer cells resulting in serious side effects on patients. Thus, the need for complementary treatments that improve the patient's response to cancer therapy is highly important. To predict and evaluate the physicochemical characteristics and potential anticancer activity of the peptides identified from S. hispanica protein fraction <1 kDa through the use of in silico tools. Peptides derived from Salvia hispanica's protein fraction <1 kDa were identified and analyzed for the prediction of their physicochemical properties. The characterized peptide sequences were then submitted to a multi-criteria decision analysis to identify the peptides that possess the characteristics to potentially exert anticancer activity. Through molecular docking analysis, the potential anticancer activity of the Potentially Anticancer Peptide (PAP)-1, PAP-2, PAP-3, PAP-4, and PAP-5 was estimated by their binding interactions with cancer and apoptosis-related molecules. All five evaluated PAPs exhibited strong binding interactions (< -100 kcal/mol). However, PAP-3 showed the lowest binding free energies with several of the targets. Thus, PAP-3 shows potential to be used as a nutraceutical or ingredient for functional foods that adjuvate in cancer treatment. Conclusions: Through the molecular docking studies, the binding of the PAPs to target molecules of interest for cancer treatment was successfully simulated, from which PAP-3 exhibited the lowest binding free energies. Further in vitro and in vivo studies are required to validate the predictions obtained by the in silico analysis.Communicated by Ramaswamy H. Sarma.

Investigation of the effects of Theranekron and Sorafenib treatments on carcinogenesis, apoptosis and biochemical profile in hepatocellular carcinoma in rats

This study aimed to investigate the effects of Tarantula cubensis alcohol extract (TCAE, Theranekron) and Sorafenib (S) treatments on carcinogenesis, apoptosis and biochemical profile of rats with experimentally induced hepatocellular carcinoma (HCC). In the presented study, 58 male rats were divided into 7 groups; Negative Control (NC, n = 6), NC + TCAE (NCT, n = 6), NC + Sorafenib (NCS, n = 6), Positive Control (PC, n = 10), Positive Control + TCAE (PCT, n = 10), Positive Control + Sorafenib (PCS, n = 10), Positive Control + TCAE + Sorafenib (PCTS, n = 10). The active ingredients Diethylnitrosamine (DEN, 120 mg/kg, single dose) and Nitrosomorpholine (NMOR, 50 ppm, 21 weeks orally) were used to induce HCC in rats. At the end of the experiment, the animals were euthanized under appropriate conditions and samples were collected for biochemical and pathological investigations. In the PC group, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transpeptidase (GGT) levels were higher (p < 0.001) and urea levels were lower (p < 0.001) compared to all other groups. Treatment groups reorganized the relevant markers (ALT, AST, GGT, and urea). A significant increase was detected in Caspase-10, Caspase-3 and Granzyme-B (GrzB) (p < 0.001) in blood and Caspase-10 and GrzB (p < 0.05) in liver tissue in PCT, PCS and PCTS groups compared to the PC group. Histopathological examination revealed that the PC group showed cancer morphology, and the treatment groups caused a decrease in tumor incidence and size. Our current findings suggest that the mechanism of action of TCAE in HCC is through the NKs/CTLs-GrzB-Casp10-Casp3 signaling pathway and can be used in combination with chemotherapy drugs for the development of future drug designs.

Natural bioactive compounds and STAT3 against hepatocellular carcinoma: An update

Hepatocellular carcinoma (HCC) is a challenging and very fatal liver cancer. The signal transducer and activator of transcription 3 (STAT3) pathway is a crucial regulator of tumor development and are ubiquitously active in HCC. Therefore, targeting STAT3 has emerged as a promising approach for preventing and treating HCC. Various natural bioactive compounds (NBCs) have been proven to target STAT3 and have the potential to prevent and treat HCC as STAT3 inhibitors. Numerous kinds of STAT3 inhibitors have been identified, including small molecule inhibitors, peptide inhibitors, and oligonucleotide inhibitors. Due to the undesirable side effects of the conventional therapeutic drugs against HCC, the focus is shifted to NBCs derived from plants and other natural sources. NBCs can be broadly classified into the categories of terpenes, alkaloids, carotenoids, and phenols. Most of the compounds belong to the family of terpenes, which prevent tumorigenesis by inhibiting STAT3 nuclear translocation. Further, through STAT3 inhibition, terpenes downregulate matrix metalloprotease 2 (MMP2), matrix metalloprotease 9 (MMP9) and vascular endothelial growth factor (VEGF), modulating metastasis. Terpenes also suppress the anti-apoptotic proteins and cell cycle markers. This review provides comprehensive information related to STAT3 abrogation by NBCs in HCC with in vitro and in vivo evidences.

CYP2E1 triggered GRP78/ATF6/CHOP signaling axis inhibit apoptosis and promotes progression of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related death worldwide. Cytochrome P450 2E1 (CYP2E1) is an enzyme, primarily involved in the metabolism of xenobiotics and procarcinogens. The present study was designed to investigate the potential role of CYP2E1 triggered endoplasmic reticulum stress in the progression of HCC through inhibition of apoptosis. In vitro CYP2E1 promotes HepG2 cell migration, reduced chromatin condensation, enhanced intracellular ROS accumulation and induce cell cycle progression. Conversely this effect was averted by CYP2E1 siRNA, selective inhibitor Diallyl sulphide (DAS) and antioxidants (vitamin C and E). In vivo Diethylnitrosamine (DEN) induced HCC rats showed decreased body weight and increased relative liver weight. Moreover, macro trabecular-massive HCC (MTM-HCC) histological subtyping showed pathological features like well-differentiated tumors, micro-trabecular and pseudo glandular patterns, megakaryocytes and cholestasis. Masson's trichrome staining revealed an intensive accumulation of collagen fibers in the extracellular matrix (ECM). Increased CYP2E1, VEGF and PCNA enhance the carcinogenicity as revealed in immunohistochemistry results. Immunoblot analysis showed reduced expression of copper-zinc superoxide dismutase (CuZnSOD) and manganese superoxide dismutase (MnSOD) in cytosolic as well as mitochondrial fraction of rat liver tissue respectively. Also, increased level of CYP2E1 stimulated the upregulation of unfolded proteins response (UPR) and ER stress-related proteins such as Glucose regulatory protein 78 (GRP78), activating transcription factor 6 (ATF6) and CCAAT enhancer-binding protein (C/EBP) homologous protein (CHOP). Meanwhile, CYP2E1 stimulated ER-stress reduces BCL2 and downregulates the cleaved caspase 3 thus suppresses apoptosis. in. Furthermore, immunofluorescence revealed increased expression level of α-SMA in the HCC rat liver tissue. The level of CYP2E1 mRNA was significantly increased. Altogether, these findings indicate that CYP2E1 has a dynamic role in the pathogenesis of HCC and might be a budding agent in liver carcinogenesis therapy.

Design and synthesis of novel hexahydrobenzo[4,5]thieno[2,3-d]pyrimidine derivatives as potential anticancer agents with antiangiogenic activity via VEGFR-2 inhibition, and down-regulation of PI3K/AKT/mTOR signaling pathway

New thieno[2,3-d]pyrimidine derivatives were designed and synthesized. The National Cancer Institute (NCI) evaluated the synthesized novel compounds against a panel of 60 tumor cell lines for their antiproliferative activity. Compounds 6b, 6f, and 6g showed potent anticancer activity at 10 µM dose, with mean GI of 20.86%, 76.41%, and 31.49%, respectively. Compound 6f was selected for five-dose concentrations evaluation. Compound 6f scored a submicromolar range of GI50 values against 10 cancer cell lines, indicating broad-spectrum and potent antiproliferative activity. Compound 6f TGI values were recorded in the cytostatic range of 4.02-95.1 µM. In comparison to sorafenib, the tested compounds 6b, 6f, and 6g inhibited VEGFR-2 with IC50 values of 0.290 ± 0.032, 0.066 ± 0.004, and 0.16 ± 0.006 µM, correspondingly. Compound 6f significantly reduced the total VEGFR-2 expression and its phosphorylation. Additionally, 6f reduced the phosphorylation of PI3K, Akt, and mTOR pathway proteins. Moreover, the migratory potential of HUVECs was significantly reduced, after 72 h of treatment with compound 6f, resulting in disrupted wound healing patterns which verified the angiogenesis suppression properties of compound 6f. Compound 6f increased the total apoptosis percentage by 21.27-fold compared to sorafenib, which caused a 24.11-fold increase in the total apoptosis percentage. This apoptotic activity was accompanied by a 7.81-fold increase in the level of apoptotic caspase-3. Furthermore, the cell cycle analysis revealed that the target derivative 6f reduced cellular proliferation and induced an arrest in HCT-15 colon cancer cell cycle at the S phase. Molecular modeling was used to determine the binding profile and affinity of derivative 6f toward the VEGFR-2 active site.

Cancer chemo-preventive role of grape seed oil and cisplatin as a combination adjuvant therapy in the treatment of tongue squamous cell carcinoma: A biological in-vitro study

OBJECTIVES

Grape seed oil (GSO) has recently gained popularity due to its anticancer properties. This study aimed to investigate the efficacy of combining cisplatin (CP) and GSO in tongue squamous cell carcinoma (TSCC) treatment.

METHODS

In this study, human tongue carcinoma cell line (HNO-97) was treated with CP and GSO alone or in combination. The effects of CP and GSO on cytotoxicity and cell cycle arrest were studied using the MTT assay and flowcytometry, respectively. The apoptotic markers, including p53 and caspase 8, were assessed using reverse-transcription polymerase chain reaction (RT-PCR), caspase 3 using immunohistochemistry, and the angiogenic marker vascular endothelial growth factor (VEGF) using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The IC50 drug concentrations were found to be 16.4 ug/mL of GSO and 2.18 ug/mL of CP. When compared to the untreated control group, the percentage of S phase cells and apoptotic cells was significantly higher in the GSO, CP, and GSO/CP combination therapy groups. Furthermore, p53, caspase 8, caspase 3 expression were significantly upregulated in the GSO-and CP-treated groups, with evident upregulation with GSO/CP combination therapy. However, VEGF levels were significantly lower in the GSO-, CP-, and combined GSO/CP-treated groups.

CONCLUSIONS

GSO has both an apoptotic and antiangiogenic effect in the treatment of TSCC, suggesting a new strategy for phytochemical-based combination therapy.

Apoptotic proteins with non-apoptotic activity: expression and function in cancer

Apoptosis is a process of programmed cell death in which a cell commits suicide while maintaining the integrity and architecture of the tissue as a whole. Apoptosis involves activation of one of two major pathways: the extrinsic pathway, where extracellular pro-apoptotic signals, transduced through plasma membrane death receptors, activate a caspase cascade leading to apoptosis. The second, the intrinsic apoptotic pathway, where damaged DNA, oxidative stress, or chemicals, induce the release of pro-apoptotic proteins from the mitochondria, leading to the activation of caspase-dependent and independent apoptosis. However, it has recently become apparent that proteins involved in apoptosis also exhibit non-cell death-related physiological functions that are related to the cell cycle, differentiation, metabolism, inflammation or immunity. Such non-conventional activities were predominantly reported in non-cancer cells although, recently, such a dual function for pro-apoptotic proteins has also been reported in cancers where they are overexpressed. Interestingly, some apoptotic proteins translocate to the nucleus in order to perform a non-apoptotic function. In this review, we summarize the unconventional roles of the apoptotic proteins from a functional perspective, while focusing on two mitochondrial proteins: VDAC1 and SMAC/Diablo. Despite having pro-apoptotic functions, these proteins are overexpressed in cancers and this apparent paradox and the associated pathophysiological implications will be discussed. We will also present possible mechanisms underlying the switch from apoptotic to non-apoptotic activities although a deeper investigation into the process awaits further study.

Mechanisms of Arachidonic Acid In Vitro Tumoricidal Impact

To promote the potential of arachidonic acid (ARA) for cancer prevention and management, experiments were implemented to disclose the mechanisms of its tumoricidal action. Hepatocellular, lung, and breast carcinoma and normal hepatocytes cell lines were exposed to 0 or 50 μM ARA for 30 min and then assessed for proliferative capacity, surface membrane-associated sphingomyelin (SM) content, neutral sphingomyelinase (nSMase) activity, beta 2 microglobulin (β2 m) expression, and ceramide (Cer) levels. Reactive oxygen species (ROS) content and caspase 3/7 activity were evaluated. Exposure to ARA for 30 min led to impairment of the tumor cells' proliferative capacity and revealed that the different cell lines display remarkably similar surface membrane SM content but diverse responses to ARA treatment. Arachidonic acid tumoricidal impact was shown to be associated with nSMase activation, exposure of cell surface membrane β2 m to antibody binding, and hydrolysis of SM to Cer, which accumulated on the cell surface and in the cytosol. The ARA and Cer-mediated inhibition of tumor cell viability appeared to be independent of ROS generation or caspase 3/7 activation. The data were compared and contrasted to findings reported in the literature on ARA tumoricidal mechanisms.

The cytokine receptor CRLF3 is a human neuroprotective EV-3 (Epo) receptor

The evolutionary conserved orphan cytokine receptor-like factor 3 (CRLF3) has been implicated in human disease, vertebrate hematopoiesis and insect neuroprotection. While its specific functions are elusive, experimental evidence points toward a general role in cell homeostasis. Erythropoietin (Epo) is a major regulator of vertebrate hematopoiesis and a general cytoprotective cytokine. Erythropoietic functions mediated by classical Epo receptor are understood in great detail whereas Epo-mediated cytoprotective mechanisms are more complex due to involvement of additional Epo receptors and a non-erythropoietic splice variant with selectivity for certain receptors. In the present study, we show that the human CRLF3 mediates neuroprotection upon activation with the natural Epo splice variant EV-3. We generated CRLF3 knock-out iPSC lines and differentiated them toward the neuronal lineage. While apoptotic death of rotenone-challenged wild type iPSC-derived neurons was prevented by EV-3, EV-3-mediated neuroprotection was absent in CRLF3 knock-out neurons. Rotenone-induced apoptosis and EV-3-mediated neuroprotection were associated with differential expression of pro-and anti-apoptotic genes. Our data characterize human CRLF3 as a receptor involved in Epo-mediated neuroprotection and identify CRLF3 as the first known receptor for EV-3.

Recent Advances in the Enzyme-Activatable Organic Fluorescent Probes for Tumor Imaging and Therapy

The exploration of advanced probes for cancer diagnosis and treatment is of high importance in fundamental research and clinical practice. In comparison with the traditional "always-on" probes, the emerging activatable probes enjoy advantages in promoted accuracy for tumor theranostics by specifically releasing or activating fluorophores at the targeting sites. The main designing principle for these probes is to incorporate responsive groups that can specifically react with the biomarkers (e. g., enzymes) involved in tumorigenesis and progression, realizing the controlled activation in tumors. In this review, we summarize the latest advances in the molecular design and biomedical application of enzyme-responsive organic fluorescent probes. Particularly, the fluorophores can be endowed with ability of generating reactive oxygen species (ROS) to afford the photosensitizers, highlighting the potential of these probes in simultaneous tumor imaging and therapy with rational design. We hope that this review could inspire more research interests in the development of tumor-targeting theranostic probes for advanced biological studies.

Nicotinonitrile-derived apoptotic inducers: Design, synthesis, X-ray crystal structure and Pim kinase inhibition

Although a plethora of targeted anticancer small molecule drugs became available, the low response rate and drug resistance imply the continuous need for expanding the anticancer chemical space. In this study, a novel series of nicotinonitrile derivatives was designed, synthesized and evaluated for cytotoxic activities in HepG2 and MCF-7 cells. All derivatives showed high to moderate cytotoxic activity against both cell lines, with cell-type and chemotype-dependent cytotoxic potential. The normal HEK-293 T cells were ca. 50-fold less susceptible to the cytotoxic effect of the inhibitors. The in vitro enzyme inhibitory activity of selected active cytotoxic derivatives 8c, 8e, 9a, 9e and 12 showed that they have sub- to one digit micromolar 50 % inhibitory concentration (IC₅₀) against the three Pim kinase isoforms, with 8e being the most potent (IC₅₀ ≤ 0.28 μM against three Pim kinases), comparable to the pan kinase inhibitor, Staurosporine. In HepG2, 8e induced cell cycle arrest at the G2/M phase. Apoptotic mechanistic studies with 8c and 8e in HepG2 cells, indicated a significant upregulation in both P53 and caspase-3 relative gene expression, as well as increased Bax/Bcl-2 protein expression level. Further, docking studies combined with molecular dynamic simulation showed a stable complex with high binding affinity of 8e to Pim-1 kinase; exploiting a negative electrostatic potential surface interaction with the added dimethyl amino group in the new compounds. Moreover, in silico ADME profile prediction indicated that all compounds are orally bioavailable and most of them can penetrate the blood-brain barrier. This study presents novel nicotinonitrile derivatives as auspicious hits for further optimization as antiproliferative agents against liver cancer cells and promising pan Pim kinase inhibitors at submicromolar concentrations.

Investigations of nitazoxanide molecular targets and pathways for the treatment of hepatocellular carcinoma using network pharmacology and molecular docking

Nitazoxanide has been investigated for colorectal cancer and breast cancer. However, its molecular targets and pathways have not yet been explored for hepatocellular carcinoma (HCC) treatment. Utilizing a network pharmacology approach, nitazoxanide’s potential targets and molecular pathways for HCC treatment were investigated. HCC targets were extracted from the GeneCards database. Potential targets of nitazoxanide were predicted using Swiss Target Prediction and Super Pred. Intersecting targets were analyzed with VENNY online tool. Using Cytoscape, a protein-protein interaction (PPI), cluster, and core targets-pathways networks were constructed. Using the Database for Annotation, Visualization and Integrated Discovery (DAVID), gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted. The nitazoxanide was molecularly docked with anti-HCC core targets by employing Auto Dock Vina. A total of 168 potential targets of nitazoxanide, 13,415 HCC-related targets, and 153 intersecting targets were identified. The top eight anti-HCC core targets were identified: SRC, EGFR, CASP3, MMP9, mTOR, HIF1A, ERBB2, and PPARG. GO enrichment analysis showed that nitazoxanide might have anti-HCC effects by affecting gene targets involved in multiple biological processes (BP) (protein phosphorylation, transmembrane receptor protein tyrosine kinase (RTKs) signaling pathway, positive regulation of MAP kinase activity, etc.). KEGG pathways and core targets-pathways network analysis indicated that pathways in cancer and proteoglycans in cancer are two key pathways that significantly contribute to the anti-HCC effects of nitazoxanide. Results of molecular docking demonstrated the potential for active interaction between the top eight anti-HCC core targets and nitazoxanide. Our research offers a theoretical basis for the notion that nitazoxanide may have distinct therapeutic effects in HCC, and the identified pharmacological targets and pathways might function as biomarkers for HCC therapy.

The mechanism of dioscin preventing lung cancer based on network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Dioscorea nipponica Makino as a Chinese folk medicine has been used for the treatment of chronic bronchitis, cough, and asthma. Several studies have established the antimetastatic potential of Dioscorea nipponica Makino extract. Dioscin is a major bioactive compound in Dioscorea nipponica Makino and has anti-tumor property in lung cancer cell lines. However, the preventive effect of dioscin against lung cancer and its key mechanism haven't been identified yet.

AIM OF STUDY

To identify the prevention effect of dioscin on lung cancer and explore its key mechanism based on network pharmacology and experimental validation.

METHODS

The potential targets of dioscin were obtained from the HERB database. The therapeutic targets of lung cancer were acquired from the GeneCards database. Protein-protein interaction network (PPI) was constructed in the STRING 11.0 database. The David database was used for enrichment analysis. Molecular Docking was finished by the AutoDock Vina. NSCLC cell lines and mouse lung cancer model were used to confirm the prevention effect of dioscin on lung cancer and its key mechanism.

RESULTS

76 potential targets of dioscin were identified to be involved in lung cancer treatment, which refer to 512 biological processes, 47 molecular functions, 77 cellular components and 107 signal pathways. The molecular docking suggested that dioscin might bind to AKT1, Caspase3, TP53, C-JUN and IL-6. The DARTS indicated that dioscin could bind to AKT1. In vitro, dioscin could decrease proliferation, invasion and migration in A549 and PC-9 cells with the significant reduction in the expression of p-AKT, MMP2, and PCNA. In vivo, dioscin could reduce lung nodules, lung injury, and mortality in mouse lung cancer model with reducing the expression of p-AKT, MMP2, PCNA and increasing the expression of active-caspase3.

CONCLUSION

Dioscin could prevent lung cancer and its key target is AKT1 kinase, a center protein of PI3K/AKT signaling pathway.

TCHis mitigate oxidative stress and improve abnormal behavior in a prenatal valproic acid-exposed rat model of autism

Objective Troxerutin is known for its anti-inflammatory and antioxidative effects in nerve impairment. The purpose of this study is to investigate the effect of troxerutin and cerebroprotein hydrolysate injections (TCHis) on prenatal valproic acid (VPA)-exposed rats. Methods The VPA was administered to pregnant rats on gestational day 12.5 to induce a model of autism. The offsprings were given the treatment of TCHis on postnatal day (PND) 21-50. On PND 43-50, the behavioral analysis of offsprings was performed after the treatment of TCHis for 1 h. On PND 50, the offsprings were harvested and the brains were collected. The hippocampus and prefrontal cortex were isolated for relevant biochemical detections. Results The administration of TCHis increased the pain sensitivity and improved abnormal social behaviors in prenatal VPA-exposed rats. Prenatal expose of VPA induced neuronal loss and apoptosis, enhanced reactive oxygen species (ROS) production, and promoted oxidative stress in hippocampus and prefrontal cortex, while these effects were reversed by the postnatal treatment of TCHis. In addition, postnatal administration of TCHis ameliorated mitochondrial function in hippocampus and prefrontal cortex of prenatal VPA-exposed rats. Conclusion This study concluded that postnatal treatment of TCHis reduced oxidative stress and ameliorated abnormal behavior in a prenatal VPA-induced rat model of autism.

Network-Pharmacology-Based Study on Active Phytochemicals and Molecular Mechanism of Cnidium monnieri in Treating Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a malignancy with a high mortality rate globally. For thousands of years, Cnidium monnieri has been used to treat human ailments and is regarded as a veritable treasure trove for drug discovery. This study has investigated the key active phytochemicals and molecular mechanisms of Cnidium monnieri implicated in curing HCC. We utilized the TCMSP database to collect data on the phytochemicals of Cnidium monnieri. The SwissTargetPrediction website tool was used to predict the targets of phytochemicals of Cnidium monnieri. HCC-related genes were retrieved from OncoDB.HCC and Liverome, two liver-cancer-related databases. Using the DAVID bioinformatic website tool, Gene Ontology (GO) and KEGG enrichment analysis were performed on the intersecting targets of HCC-related genes and active phytochemicals in Cnidium monnieri. A network of active phytochemicals and anti-HCC targets was constructed and analyzed using Cytoscape software. Molecular docking of key active phytochemicals was performed with anti-HCC targets using AutoDock Vina (version 1.2.0.). We identified 19 active phytochemicals in Cnidium monnieri, 532 potential targets of these phytochemicals, and 566 HCC-related genes. Results of GO enrichment indicated that Cnidium monnieri might be implicated in affecting gene targets involved in multiple biological processes, such as protein phosphorylation, negative regulation of the apoptotic process, which could be attributed to its anti-HCC effects. KEGG pathway analyses indicated that the PI3K-AKT signaling pathway, pathways in cancer, proteoglycans in cancer, the TNF signaling pathway, VEGF signaling pathway, ErbB signaling pathway, and EGFR tyrosine kinase inhibitor resistance are the main pathways implicated in the anti-HCC effects of Cnidium monnieri. Molecular docking analyses showed that key active phytochemicals of Cnidium monnieri, such as ar-curcumene, diosmetin, and (E)-2,3-bis(2-keto-7-methoxy-chromen-8-yl)acrolein, can bind to core therapeutic targets EGFR, CASP3, ESR1, MAPK3, CCND1, and ERBB2. The results of the present study offer clues for further investigation of the anti-HCC phytochemicals and mechanisms of Cnidium monnieri and provide a basis for developing modern anti-HCC drugs based on phytochemicals in Cnidium monnieri.

Design, synthesis and evaluation of novel 2-oxoindoline-based acetohydrazides as antitumor agents

In our search for novel small molecules activating procaspase-3, we have designed and synthesized two series of novel (E)-N'-arylidene-2-(2-oxoindolin-1-yl)acetohydrazides (4) and (Z)-2-(5-substituted-2-oxoindolin-1-yl)-N'-(2-oxoindolin-3-ylidene)acetohydrazides (5). Cytotoxic evaluation revealed that the compounds showed notable cytotoxicity toward three human cancer cell lines: colon cancer SW620, prostate cancer PC-3, and lung cancer NCI-H23. Especially, six compounds, including 4f–h and 4n–p, exhibited cytotoxicity equal or superior to positive control PAC-1, the first procaspase-3 activating compound. The most potent compound 4o was three- to five-fold more cytotoxic than PAC-1 in three cancer cell lines tested. Analysis of compounds effects on cell cycle and apoptosis demonstrated that the representative compounds 4f, 4h, 4n, 4o and 4p (especially 4o) accumulated U937 cells in S phase and substantially induced late cellular apoptosis. The results show that compound 4o would serve as a template for further design and development of novel anticancer agents.

Design, Synthesis and Evaluation of Novel (E)-N'-((1-(4-chlorobenzyl)-1H-indol-3-yl)methylene)-2-(4-oxoquinazolin-3(4H)-yl)acetohydrazides as Antitumor Agents

BACKGROUND

Herein, we have designed and synthesized a series of the novel (E)-N'-((1-(4-chlorobenzyl)-1H-indol-3-yl)methylene)-2-(4-oxoquinazolin-3(4H)-yl)acetohydrazides (5) as potent small molecules activating procaspase-3. The compounds were designed by the amalgamation of structural features of PAC-1 (the first procaspase-3 activator) and oncrasin-1, one potential anticancer agent.

METHODS

The target acetohydrazides (5a-m) were prepared via the Niementowski condensation of anthranilic acid (1a) or 5-substituted-2-aminobenzoic acid (1b-m) and formamide. The compound libraries were evaluated for their cytotoxicity, caspase-3 activation, cell cycle analysis, and apoptosis. In addition, computational chemistry is also performed.

RESULTS

A biological evaluation revealed that all thirteen compounds designed and synthesized showed strong cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer) with eight compounds (5a, 5c-i, 5k), which were clearly more potent than both PAC-1 and oncrasin-1. In this series, four compounds including 5c, 5e, 5f, and 5h, were the most potent members with approximately 4- to 5-fold stronger than the reference compounds PAC-1 and oncrasin-1 in terms of IC50. In comparison to 5-FU, these compounds were even 18- to 29-fold more potent in terms of cytotoxicity in three human cell lines tested. In the caspase activation assay, the caspase activity was activated to 285% by compound 5e in comparison to PAC-1, the first procaspase activating compound, which was used as a control. Our docking simulation revealed that compound 5e was a potent allosteric inhibitor of procaspase-3 through chelation of inhibitory zinc ion. Physicochemical and ADMET calculations for 5e provided useful information of its suitable absorption profile and some toxicological effects that need further optimization to be developed as a promising anticancer agent.

CONCLUSION

Compound 5e has emerged as a potential hit for further design and development of caspases activators and anticancer agents.

Amelioration of oxidative stress by trans-Anethole via modulating phase I and phase II enzymes against hepatic damage induced by CCl4 in male Wistar rats

The current study was designed to assess the in vivo hepatoprotective properties of trans-Anethole, which is a principal aromatic component of star anise. The hepatoprotective effects of trans-Anethole were evaluated at three doses [40, 80, and 160 mg/kg body weight (b.wt.)] against carbon tetrachloride (CCl₄)-induced hepatic damage in male Wistar rats for 4 weeks. Forty-two male Wistar rats were equally divided into seven groups; the control (group I) received only distilled water. Rats of group II received CCl₄ (1 ml/kg b.wt.) in a 1:1 ratio of CCl₄ and olive oil via intraperitoneal doses, while rats of group III received silymarin (50 mg/kg b.wt.), followed by CCl₄ intraperitoneal doses, 3 days in a week. Rats of group IV received trans-anethole (160 mg/kg b.wt.) for 28 days as a negative control. Trans-anethole at the doses of 40, 80, and 160 mg/kg b.wt. was administered to groups V, VI, and VII, respectively, for 28 days, followed by CCl₄ (i.p). Results showed that CCl₄ treatment (group II) elevated the levels of different serum markers like aspartate aminotransferase (AST) by 4.74 fold, alanine aminotransferase (ALT) by 3.47 fold, aspartate alkaline phosphatase (ALP) by 3.55 fold, direct bilirubin by 3.48 fold, and total bilirubin by 2.38 fold in contrast to control. Furthermore, it was found that the decreased levels of liver antioxidant enzymes viz. catalase (CAT) and glutathione reductase (GR) were significantly modulated by the pre-administration of rats with different doses (40, 80, and 160 mg/kg b.wt.) of trans-anethole. Furthermore, pre-treatment of trans-anethole reduced the level of phase I enzymes and elevated the level of phase II detoxifying enzymes. Histopathological investigations showed that the treatment with trans-anethole was effective in ameliorating CCl₄-induced liver injury and restored the normal hepatic architecture. Moreover, trans-anethole restored p53 and cyclin D levels in liver tissue relative to group II. Western blot analysis revealed that the trans-anethole treatment downregulated the expression of Bax and caspase-3 while upregulated the expression of Bcl-xL. Collectively, the findings of the study showed the strong efficacy of trans-anethole in ameliorating the hepatic damage caused by CCl₄ through the modulation of antioxidants and xenobiotic-metabolizing enzymes.

Design, synthesis, anticancer evaluation, and molecular modelling studies of novel tolmetin derivatives as potential VEGFR-2 inhibitors and apoptosis inducers

Novel tolmetin derivatives 5a-f to 8a-c were designed, synthesised, and evaluated for antiproliferative activity by NCI (USA) against a panel of 60 tumour cell lines. The cytotoxic activity of the most active tolmetin derivatives 5b and 5c was examined against HL-60, HCT-15, and UO-31 tumour cell lines. Compound 5b was found to be the most potent derivative against HL-60, HCT-15, and UO-31 cell lines with IC50 values of 10.32 ± 0.55, 6.62 ± 0.35, and 7.69 ± 0.41 µM, respectively. Molecular modelling studies of derivative 5b towards the VEGFR-2 active site were performed. Compound 5b displayed high inhibitory activity against VEGFR-2 (IC50 = 0.20 µM). It extremely reduced the HUVECs migration potential exhibiting deeply reduced wound healing patterns after 72 h. It induced apoptosis in HCT-15 cells (52.72-fold). This evidence was supported by an increase in the level of apoptotic caspases-3, -8, and -9 by 7.808-, 1.867-, and 7.622-fold, respectively. Compound 5b arrested the cell cycle in the G0/G1 phase. Furthermore, the ADME studies showed that compound 5b possessed promising pharmacokinetic properties.

Repurposing Antipsychotics for Cancer Treatment

Cancer is a leading cause of death worldwide, with approximately 19 million new cases each year. Lately, several novel chemotherapeutic drugs have been introduced, efficiently inhibiting tumor growth and proliferation. However, developing a new drug is a time- and money-consuming process, requiring around 1 billion dollars and nearly ten years, with only a minority of the initially effective anti-cancer drugs experimentally finally being efficient in human clinical trials. Drug repurposing for cancer treatment is an optimal alternative as the safety of these drugs has been previously tested, and thus, in case of successful preclinical studies, can be introduced faster and with a lower cost into phase 3 clinical trials. Antipsychotic drugs are associated with anti-cancer properties and, lately, there has been an increasing interest in their role in cancer treatment. In the present review, we discussed in detail the in-vitro and in-vivo properties of the most common typical and atypical antipsychotics, along with their mechanism of action.

Design, synthesis, and evaluation of novel (E)-N'-(3-allyl-2-hydroxy)benzylidene-2-(4-oxoquinazolin-3(4H)-yl)acetohydrazides as antitumor agents

In our continuing search for novel small-molecule anticancer agents, we designed and synthesized a series of novel (E)-N'-(3-allyl-2-hydroxy)benzylidene-2-(4-oxoquinazolin-3(4H)-yl)acetohydrazides (5), focusing on the modification of substitution in the quinazolin-4(3H)-one moiety. The biological evaluation showed that all 13 designed and synthesized compounds displayed significant cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer). The most potent compound 5l displayed cytotoxicity up to 213-fold more potent than 5-fluorouracil and 87-fold more potent than PAC-1, the first procaspase-activating compound. Structure-activity relationship analysis revealed that substitution of either electron-withdrawing or electron-releasing groups at positions 6 or 7 on the quinazolin-4(3H)-4-one moiety increased the cytotoxicity of the compounds, but substitution at position 6 seemed to be more favorable. In the caspase activation assay, compound 5l was found to activate the caspase activity by 291% in comparison to PAC-1, which was used as a control. Further docking simulation also revealed that this compound may be a potent allosteric inhibitor of procaspase-3 through chelation of the inhibitory zinc ion. Physicochemical and ADMET calculations for 5l provided useful information of its suitable absorption profile and some toxicological effects that need further optimization to be developed as a promising anticancer agent.

Protective Effect of Nerium Oleander Distillate and Tarantula Cubensis Alcoholic Extract on Cancer Biomarkers on Colon and Liver Tissues of Rats with Experimental Colon Cancer

BACKGROUND

Colon cancers are among the three major cancer types that result in death. The research for effective treatment continues.

OBJECTIVE

The aim of this study is to determine the effects of Tarantula cubensis alcoholic extract (TCAE) and Nerium oleander (NO) distillate on the levels of midkine, TGF-β, VEGF, AFP, COX-2, IGF and caspase 3 in liver and colon tissues of experimentally induced colon cancer in rats.

METHOD

The liver and colon tissues of the rats were divided into Control, Colon Cancer (AZM), AZM+TCAE and AZM+NO groups and they were homogenized. The levels of midkine, TGF-β, VEGF, AFP, COX-2, IGF and caspase 3 in the colon and liver tissues were measured by ELISA kits.

RESULTS

All parameters levels of colon and liver tissues in the AZM group were generally higher (p<0.05) than the Control group. TCAE and NO prevented (p<0.05) the increases in midkine, TGF-β, VEGF, AFP, COX-2, IGF and caspase-3 levels in the colon. NO prevented increase of all parameters except for IGF level, while TCAE prevented (p<0.05) the increase of all values apart from COX-2 and IGF levels in the liver.

CONCLUSION

NO and TCAE may prevented at the specified marker levels of colon in the AZM induced colon cancer. The increases the level of parameters in the liver are not as severe as in the colon, due to the 18-week study period may not be sufficient for liver metastasis formationIn the future molecular studies should be done to determine the mechanisms and pathways of them more clearly.

Synthesis and Biological Evaluation of Novel 2-imino-4-thiazolidinones as Potential Antitumor Agents for Glioblastoma

AIMS

The purpose of our study was to explore the molecular hybridization between 2-imino-4-thizolidione and piridinic scaffolds and its potential antitumor activity.

BACKGROUND

Glioblastoma is the most aggressive glioma tumor clinically diagnosed malignant and highly recurrent primary brain tumor type. The standard of treatment for a glioblastoma is surgery, followed by radiation and chemotherapy using temozolomide. However, the chemoresistance has become the main barrier to treatment success. 2-imino-4-thiazolidinones are an important class of heterocyclic compounds that feature anticancer activity; however the antiglioblastoma activity is yet to be explored.

OBJECTIVE

To synthesize and characterize a series of novel 2-imino-4-thiazolidinones and evaluate their antiglioblastoma activity.

METHOD

The 2-imino-4-thiazolidinone (5a-p) was synthesized according to the literature with modifications. Compounds were identified and characterized using spectroscopic analysis and X-ray diffraction. The antitumor activity was analyzed by 3-(4,5- dimethyl)-2,5-diphenyltetrazolium bromide (MTT) assay both in primary astrocyte and glioma (C6). Apoptosis and cell cycle phase were determined by flow cytometry analysis. The expression of caspase-3/7 was measured by luminescence assay. Oxidative stress parameters as: determination of reactive oxygen species (ROS), superoxide dismutase (SOD) activity, catalase (CAT) activity and total sulfhydryl content quantification were analyzed by colorimetric assays according to literature.

RESULTS

Among sixteen synthesized compounds, three displayed potent antitumor activities against tested glioblastoma cell line showed IC50 values well below the standard drug temozolomide. Therefore, compounds 5a, 5l and 5p were evaluated using cell cycle and death analysis, due to potent toxicity (2.17±1.17, 6.24±0.59, 2.93±1.12µM, respectively) in C6 cell line. The mechanism of action studies demonstrated that 5a and 5l induced apoptosis significantly increase the percentage of cells in Sub-G1 phase in the absence of necrosis. Consistent with these results, caspase-3/7 assay revealed that 5l presents pro-apoptotic activity due to the significant stimulation of caspases-3/7. Moreover, 5a, 5l and 5p increased antioxidant defense and decreased reactive oxygen species (ROS) production.

CONCLUSION

The compounds were synthesized with good yield and three of these presented (5a, 5l and 5p) good cytotoxicity against C6 cell line. Both affected cell cycle distribution via arresting more C6 cell line at Sub-G1 phase promoting apoptosis. Furthermore, 5a, 5l and 5p modulated redox status. These findings suggest that these compounds can be considered as promising lead molecules for further development of potential antitumor agents.

M2 macrophage-derived exosomes carry miR-1271-5p to alleviate cardiac injury in acute myocardial infarction through down-regulating SOX6

BACKGROUND

Emerging evidence has indicated that exosomes serve as key regulators in acute myocardial infarction (AMI). This study was determined to investigate the effect of M2 macrophage-derived exosomes (M2-Exos) in AMI and the further mechanism.

METHODS

M2 macrophages were induced and M2-exos were isolated and verified. The AMI mouse model was prepared by ligation of the left anterior descending coronary artery (LAD) and then intravenously injected with the isolated M2-exos. The mouse cardiac function was assessed by echocardiography. Hematoxylin and eosin (HE) staining and TUNEL assay were conducted to examine myocardial lesion and apoptosis in cardiac tissues. The expressions of associated molecules were detected by quantitative real time-PCR (qRT-PCR) and western blot. MTT assay, Flow cytometry and Dual-luciferase reporter assay were carried out to detect cell viability, apoptosis and the interaction of miRNA and the target.

RESULT

M2-Exos could promote cardiac repair in AMI mice. M2-Exos suppressed apoptosis and enhanced viability of hypoxia-induced cardiomyocytes through delivery of miR-1271-5p. SOX6 is a direct target of miR-1271-5p. miR-1271-5p decreased cardiomyocyte apoptosis induced by hypoxia and alleviated cardiac injury in AMI via down-regulating SOX6 expression.

CONCLUSION

We identified that M2-Exos could carry miR-1271-5p to reduce apoptosis of cardiomyocytes and promote cardiac repair via down-regulating SOX6.

Research progress of MEK1/2 inhibitors and degraders in the treatment of cancer

Mitogen-activated protein kinase kinases 1 and 2 (MEK1/2) are the crucial part of the RAS-RAF-MEK-ERK pathway (or ERK pathway), which is involved in the regulation of various cellular processes including proliferation, survival, and differentiation et al. Targeting MEK has become an important strategy for cancer therapy, and 4 MEK inhibitors (MEKis) have been approved by FDA to date. However, the application of MEKis is limited due to acquired resistance under long-term treatment. Fortunately, an emerging technology, named proteolysis targeting chimera (PROTAC), could break through this limitation by inducing MEK1/2 degradation. Compared to MEKis, MEK1/2 PROTAC is rarely studied and only three MEK1/2 PROTAC molecules, have been reported until now. This paper will outline the ERK pathway and the mechanism and research progress of MEK1/2 inhibitors, but focus on the development of MEK degraders and their optimization strategies. PAC-1 strategy which can induce MEK degradation indirectly, other PROTACs on ERK pathway, the advantages and challenges of PROTAC technology will be subsequently discussed.

Design, synthesis, and evaluation of novel N'-substituted-1-(4-chlorobenzyl)-1H-indol-3-carbohydrazides as antitumor agents

In continuity of our search for novel anticancer agents acting as procaspase activators, we have designed and synthesised two series of (E)-N′-benzylidene-carbohydrazides (4a–m) and (Z)-N'-(2-oxoindolin-3-ylidene)carbohydrazides (5a–g) incorporating 1-(4-chlorobenzyl)-1H-indole core. Bioevaluation showed that the compounds, especially compounds in series 4a–m, exhibited potent cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer). Within series 4a–m, compounds with 2-OH substituent (4g–i) exhibited very strong cytotoxicity in three human cancer cell lines assayed with IC₅₀ values in the range of 0.56–0.83 µM. In particular, two compounds 4d and 4f bearing 4-Cl and 4-NO₂ substituents, respectively, were the most potent in term of cytotoxicity with IC₅₀ values of 0.011–0.001 µM. In caspase activation assay, compounds 4b and 4f were found to activate caspase activity by 314.3 and 270.7% relative to PAC-1. This investigation has demonstrated the potential of these simple acetohydrazides, especially compounds 4b, 4d, and 4f, as anticancer agents.

New Acetohydrazides Incorporating 2-Oxoindoline and 4-Oxoquinazoline: Synthesis and Evaluation of Cytotoxicity and Caspase Activation Activity

In our search for new small molecules activating procaspase-3, we have designed and synthesized a series of new acetohydrazides incorporating both 2-oxoindoline and 4-oxoquinazoline scaffolds. Biological evaluation showed that a number of these acetohydrazides were comparably or even more cytotoxic against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer) in comparison to PAC-1, a first procaspase-3 activating compound, which was used as a positive control. One of those new compounds, 2-(6-chloro-4-oxoquinazolin-3(4H)-yl)-N'-[(3Z)-5-methyl-2-oxo-1,2-dihydro-3H-indol-3-ylidene]acetohydrazide activated the caspase-3 activity in U937 human lymphoma cells by 5-fold higher than the untreated control. Three of the new compounds significantly induced necrosis and apoptosis in U937 cells.

Procaspase-3 Overexpression in Cancer: A Paradoxical Observation with Therapeutic Potential

Many anticancer strategies rely on the promotion of apoptosis in cancer cells as a means to shrink tumors. Crucial for apoptotic function are executioner caspases, most notably caspase-3, that proteolyze a variety of proteins, inducing cell death. Paradoxically, overexpression of procaspase-3 (PC-3), the low-activity zymogen precursor to caspase-3, has been reported in a variety of cancer types. Until recently, this counterintuitive overexpression of a pro-apoptotic protein in cancer has been puzzling. Recent studies suggest subapoptotic caspase-3 activity may promote oncogenic transformation, a possible explanation for the enigmatic overexpression of PC-3. Herein, the overexpression of PC-3 in cancer and its mechanistic basis is reviewed; collectively, the data suggest the potential for exploitation of PC-3 overexpression with PC-3 activators as a targeted anticancer strategy.

Association between CASP3 polymorphisms and overall cancer risk: A meta-analysis of case-control studies

Several studies inspected the relationship between caspase-3 (CASP3) polymorphisms and the risk of several human cancers, but the findings remain controversial. We conducted a meta-analysis aiming to inspect the association between CASP3 rs1049216 T>C, rs12108497 C>T, rs4647603 G>A, rs4647602 C>A, rs6948 T>G, rs2705897 A>C, and rs113420705 G>A polymorphisms and cancer risk. Eligible studies were recognized by searching the Web of Science, PubMed, Scopus, and Google Scholar databases. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to quantitatively evaluate the association between each polymorphism of CASP3 and cancer risk. The rs4647603 variant significantly increased the risk of cancer in an overdominant (OR, 1.44; 95% CI, 1.03-2.01; P = 0.03; AG vs AA+GG) inheritance model. Regarding the rs4647602 variant, the findings revealed that this variant was associated with protection against cancer in homozygous codominant (OR, 0.67; 95% CI, 0.56-0.80; P < 0.00001; AA vs CC), dominant (OR, 0.84; 95% CI, 0.73-0.96; P = 0.009; AC+AA vs CC), recessive (OR, 0.70; 95% CI, 0.61-0.79; P < 0.00001; AA vs AC+CC), and allele (OR, 0.81; 95% CI, 0.75-0.88; P = 0.00001; A vs C) models. The findings suggested that the rs2705897 variant significantly decreased the risk of cancer in heterozygous codominant (OR, 0.80; 95% CI, 0.67-0.94; P = 0.009; AC vs AA), dominant (OR, 0.81; 95% CI, 0.69-0.95; P = 0.009; AC+CC vs AA), overdominant (OR, 0.80; 95% CI, 0.68-0.95; P = 0.01; AC vs CC+AA), and allele (OR, 0.85; 95% CI, 0.74-0.97; P = 0.02; C vs A) models. The results did not support an association between CASP3 rs1049216 and rs6948 polymorphisms and cancer risk. In summary, the findings of this meta-analysis support an association between CASP3 polymorphisms and cancer risk. Larger and well-designed studies are desired to evaluate these associations in detail.

(E)-N'-Arylidene-2-(4-oxoquinazolin-4(3H)-yl) acetohydrazides: Synthesis and evaluation of antitumor cytotoxicity and caspase activation activity

In our search for novel small molecules activating procaspase-3, we have designed and synthesised a series of novel acetohydrazides incorporating quinazolin-4(3H)-ones (5, 6, 7). Biological evaluation revealed eight compounds with significant cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer). The most potent compound 5t displayed cytotoxicity up to 5-fold more potent than 5-FU. Analysis of structure-activity relationships showed that the introduction of different substituents at C-6 position on the quinazolin-4(3H)-4-one moiety, such as 6-chloro or 6-methoxy potentially increased the cytotoxicity of the compounds. In term of caspase activation activity, several compounds were found to exhibit potent effects, (e.g. compounds 7 b, 5n, and 5l). Especially, compound 7 b activated caspases activity by almost 200% in comparison to that of PAC-1. Further docking simulation also revealed that this compound potentially is a potent allosteric inhibitor of procaspase-3.

Identification and biological evaluation of novel benzothiazole derivatives bearing a pyridine-semicarbazone moiety as apoptosis inducers via activation of procaspase-3 to caspase-3

Three series of compounds were designed, synthesized and evaluated for their in vitro anticancer activity against a procaspase-3 over-expression cancer cell line (U937) and a procaspase-3 no-expression cancer cell line (MCF-7) to rule out off-target effects. Biological evaluation led to the identification of a series of benzothiazole derivatives bearing a pyridine-semicarbazone moiety, 8j and 8k, with promising anticancer activity and remarkable selectivity. Further mechanism studies revealed that compounds 8j and 8k could induce apoptosis of cancer cells by activating procaspase-3 to caspase-3, and compound 8k exhibited the strongest procaspase-3 activation activity. Structure-activity relationships (SARs) revealed that the presence of benzothiazole and an N,N,O-donor set is crucial for the anticancer activity and selectivity, and reducing the electron density of the N,N,O-donor set results in a dramatic decline in the anticancer activity and selectivity. Furthermore, toxicity evaluation (zebrafish) in vivo and metabolic stability studies (human, rat and mouse liver microsomes) were performed to provide reliable guidance for further PK/PD studies in vivo.

Inhibition of NET-1 suppresses proliferation and promotes apoptosis of hepatocellular carcinoma cells by activating the PI3K/AKT signaling pathway

The present study aimed to elucidate the underlying mechanism of neuroepithelial cell transforming 1 (NET-1), a member of the Ras homolog gene family, in hepatocellular carcinoma (HCC). To determine the association between the expression of NET-1 and the proliferation and migration of MHCC97-H cells, the cells were transfected with NET-1 small interfering (si)RNA and si negative control. Following transfection with NET-1 siRNA, the proliferation rate of MHCC97-H cells decreased significantly and the percentage of apoptotic cells increased. The HCC cell line MHCC97-H was used in the present study as it exhibited an increased expression level of NET-1 compared with the MHCC97-L cell line. Expression levels of apoptosis-associated proteins including apoptosis regulator Bax (Bax), cyclinD1, apoptosis regulator Bcl-2 (Bcl-2) and caspase-3 were determined. Expression levels of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) and their phosphorylated forms were also measured by western blotting. Following NET-1 knockdown, the expression of Bax and cyclinD1 decreased, the expression of Bcl-2 and caspase-3 increased, and the PI3K/AKT signaling pathway was inhibited. The results of the present study suggest that inhibition of NET-1 can suppress the progression of HCC by targeting the PI3K/AKT signaling pathway. NET-1 expression level in HCC cells increased compared with normal liver cells.

N'-[(E)-Arylidene]-2-(2,3-dihydro-3-oxo-4H-1,4-benzoxazin-4-yl)-acetohydrazides: Synthesis and Evaluation of Caspase Activation Activity and Cytotoxicity

In our search for novel small cytotoxic molecules potentially activating procaspase-3, we have designed and synthesized a series of novel N'-[(E)-arylidene]-2-(2,3-dihydro-3-oxo-4H-1,4-benzoxazin-4-yl)acetohydrazides (5, 6). Biological evaluation revealed that seven compounds, including 5h, 5j, 5k, 5l, 5n, 6a, and 6b, exhibited moderate to strong cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer). Among these compounds, two most cytotoxic compounds (5h and 5j) displayed from 3- up to 10-fold higher potency than PAC-1 and 5-FU in three cancer cell lines tested. Three compounds 5j, 5k, and 5n were also found to display better caspases activation activity in comparison to PAC-1. Especially, compound 5k activated the level of caspases activity by 200% higher than that of PAC-1. From this study, three compounds 5j, 5k, and 5n could be considered as potential leads for further design and development of caspase activators and anticancer agents.

Overcoming Resistance to Targeted Anticancer Therapies through Small-Molecule-Mediated MEK Degradation

The discovery of mutant or fusion kinases that drive oncogenesis, and the subsequent approval of specific inhibitors for these enzymes, has been instrumental in the management of some cancers. However, acquired resistance remains a significant problem in the clinic, limiting the long-term effectiveness of most of these drugs. Here we demonstrate a general strategy to overcome this resistance through drug-induced MEK cleavage (via direct procaspase-3 activation) combined with targeted kinase inhibition. This combination effect is shown to be general across diverse tumor histologies (melanoma, lung cancer, and leukemia) and driver mutations (mutant BRAF or EGFR, fusion kinases EML4-ALK and BCR-ABL). Caspase-3-mediated degradation of MEK kinases results in sustained pathway inhibition and substantially delayed or eliminated resistance in cancer cells in a manner far superior to combinations with MEK inhibitors. These data suggest the generality of drug-mediated MEK kinase cleavage as a therapeutic strategy to prevent resistance to targeted anticancer therapies.

Angiogenesis for tumor vascular normalization of Endostar on hepatoma 22 tumor-bearing mice is involved in the immune response

Tumor vascular normalization involved in immune response is beneficial to the chemotherapy of tumors. Recombinant human endostatin (Endostar), an angiogenesis inhibitor, has been demonstrated to be effective in hepatocellular cancer (HCC). However, its vascular normalization in HCC and the role of the immune response in angiogenesis were unclear. In the present study, effects of Endostar on tumor vascular normalization were evaluated in hepatoma 22 (H22) tumor-bearing mice. Endostar was able to inhibit the proliferation and infiltration of tumor cells and improve α-fetoprotein, tumor necrosis factor-α and cyclic adenosine 5′-phosphate levels in the serum of H22-bearing mice, as well as the protein expression levels of the immune factors interferon-γ and cluster of differentiation (CD)86 in liver tissue. Endostar also exhibited more marked downregulation of the levels of vascular endothelial growth factor, CD31, matrix metalloproteinase (MMP)-2, MMP-9 and interleukin-17 during day 3–9 treatment, resulting in short-term normalization of tumor blood vessels. The period of vascular normalization was 3–9 days. The results of the present study demonstrated that Endostar was able to induce the period of vascular normalization, contributing to a more efficacious means of HCC treatment combined with other chemotherapy, and this effect was associated with the immune response. It may be concluded that Endostar inhibited immunity-associated angiogenesis behaviors of vascular endothelial cells in response to HCC. The results of the present study provided more reasonable possibility for the combination therapy of Endostar for the treatment of HCC.

The prophylactic and therapeutic effects of Momordica charantia methanol extract through controlling different hallmarks of the hepatocarcinogenesis

Inspite of the wide facilities for controlling cancer growth, there are little drugs to inhibit its metastasis or prevent its angiogenesis. Discovering such natural or synthetic multi-targeted agent that might strike different targets is considered as a vital goal for tumor controlling. In a previous study, the chemoprotective effect of methanol extract of Momordicacharantia (MEMC) on albino western rats bearing hepatocarcinogenesis was evaluated. The mechanism by which MEMC exert its anticancer properties was unknown. Therefore, we aimed in this study to investigate the possible role of MEMC as anti-proliferative, anti-angiogenic and anti-metastatic agent to exert its chemoprotective effect. The study was conducted on sixty albino western rats divided into six groups, 10 rats each. Diethylnitrosamine (DENA) was injected intraperitoneally (i.p.) at a dose of 200 mg/kg body weight once, 2 weeks later rats were received carbon tetrachloride (CCl₄₎ subcutaneously (3 ml/kg/week) continued for 10 weeks. MEMC was orally produced to rats (40 mg/kg) alone, as well as before, at the same time and after DENA injection. Cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), caspase-3,-8 (Casp-3,-8), histone deacetylase (HDAC) and matrixmetalloproteinases-2,-9 (MMP-2,-9) were evaluated. MEMC treatment significantly decreased Cox-2, VEGF, HDAC and MMP-2,-9 and increased Casp-3,-8 as compared to DENAgroup,which demonstrated that the anticancer effect of MEMC may be through the inhibition of angiogenesis, proliferation and metastasis and the activation of apoptosis. The improvement in before-treated group was more pronounced than that in after- and simultaneous-treated groups, indicating thatMEMC may act as a prophylactic agent more than being a therapeutic agent.

Metuzumab enhanced chemosensitivity and apoptosis in non-small cell lung carcinoma

Targeted therapeutics is used as an alternative treatment of non-small cell lung cancer (NSCLC); however, treatment effect is far from being satisfactory, and therefore identification of new targets is needed. We have previously shown that metuzumab inhibit tumor growth in vivo. The present study was performed to investigate the anti-tumor efficacy of metuzumab combined with gemcitabine and cisplatin (GP), paclitaxel and cisplatin (TP) or navelbine and cisplatin (NP) regimens in multiple NSCLC cell lines. Our results demonstrate that, in comparison to single agent metuzumab or GP treated cells, metuzumab combined with GP display inhibitory effects on tumor growth. Furthermore, we found that metuzumab elevated the sensitivity of cell lines to gemcitabine, which was identified by MTT assay. Flow cytometric analysis showed that metuzumab combined with gemcitabine (GEM) treatment led to an obvious G1 arrest and an elevated apoptosis in A549, NCI-H460 and NCI-H520 cells. Western blot analysis also demonstrated a significantly reduced level of cyclin D1, Bcl-2, and an obviously increase level of Bax and full-length caspase-3 in A549, NCI-H460 and NCI-H520 cells treated with metuzumab/gemcitabine combination in comparison with single agent treated cells. In addition, metuzumab/gemcitabine treated A549, NCI-H460 and NCI-H520 cells also demonstrated a significantly increase in deoxycytidine kinase (dCK) protein level compared with single agent metuzumab or gemcitabine treated cells. Xenograft models also demonstrated that this metuzumab/gemcitabine combination led to upregulation of dCK. Taken together, the mechanisms of metuzumab combined with GP repress tumor growth were that the combined treatment significantly inhibited the tumor cell proliferation, apoptosis and cell cycle in vitro and in vivo and at least partially by induction of dCK expression. Our results suggested that metuzumab could significantly enhance chemosensitivity of human NSCLC cells to gemcitabine. Metuzumab/gemcitabine combination treatment may be a potentially useful therapeutic regimen for NSCLC patients.

Caspase-3 expression in tumorigenesis and prognosis of buccal mucosa squamous cell carcinoma

Buccal mucosa squamous cell carcinoma (BMSCC) is the most common oral cancer in Southeast Asia. Caspase-3, a key molecule in regulating apoptosis, promotes the malignancy of various cancers. However, its role in BMSCC is unknown. Herein, we evaluated the association of caspase-3 expression with tumorigenesis and prognosis in BMSCC patients. Immunohistochemical staining indicated that the expression levels of cleaved caspase-3 (p<0.001) and caspase-3 (p<0.001) in 185 BMSCC tissues were significantly higher compared to those in the tumor adjacent normal tissues. Moreover, the high expression of caspase-3 was associated with poor pathological outcomes [advanced pathological stage (p=0.029) and larger tumor size (p=0.002)] and poor disease-free survival in patients receiving postoperative radiotherapy (p=0.030). Moreover, the low co-expression of cleaved caspase-3 and caspase-3 was associated with better disease-specific survival in patients with early pathological stage (I + II, p=0.018) or without lymph node invasion (p=0.043) compared to the positive/high expression of either or both cleaved caspase-3 and caspase-3. Taken together, cleaved caspase-3 and caspase-3 could be biomarkers for tumorigenesis in BMSCC patients. Cleaved caspase-3 and/or caspase-3 might be prognostic biomarkers for certain stages of BMSCC.

Caspase polymorphisms and prognosis of hepatocellular carcinoma

The aim of our study was to determine the impact of genetic polymorphisms in the caspase (CASP) genes on prognosis of hepatocellular carcinoma (HCC). We genotyped 7 potentially functional polymorphisms in CASP3, CASP7, CASP8, CASP9, CASP10 genes in 362 HCC patients of receiving surgical resection of HCC tumor. The associations of genotype and haplotype with overall survival (OS) and disease free survival (DFS) were analyzed by using the Cox proportional hazards model. We found that the CASP9 rs4645981 C allele was significantly associated with positive effect on DFS (P = 0.011 and 0.016 for CT+CC vs. TT in univariate and multivariate analysis, respectively), CT genotype was associated with a better OS of HCC than the TT genotype both in univariate and multivariate analysis (P = 0.048 and 0.041, respectively). Moreover, the CASP3 rs2705897 GT genotype showed marginally significant association with decreased OS and DFS, compared with the GG genotype. One haplotype TT/TG in CASP3 (constructed by rs12108497 T>C and rs2705897 T>G) was significantly associated with decreased OS and DFS, compared to the common haplotype TT/TT both in univariate analysis (P = 0.021 and 0.026, respectively) and multivariate analysis (P = 0.025 and 0.030, respectively). The haplotype GT/GT in CASP9 (constructed by rs4645978 A>G and rs4645981 C>T) was significantly associated with decreased DFS both in univariate and multivariate analysis (P = 0.012 and 0.010, respectively). In conclusion, the CASP9 rs4645981 polymorphism, CASP3 and CASP9 haplotypes may be useful prognosis markers for HCC patients with surgical resection of tumor.

Immunohistochemistry panel segregates molecular types of hepatocellular carcinoma in Brazilian autopsy cases

AIM: To assess the distribution of proteins coded by genes reported as relevant for the molecular classification of hepatocellular carcinoma (HCC).

METHODS: In this retrospective cross-sectional study, the following clinicopathological data were analyzed in 80 autopsied HCC patients: sex, age, ethnicity, alcohol intake, infection with hepatitis B and/or C virus, infection with human immunodeficiency virus, prior treatment, basic and immediate causes of death, liver weight, presence of cirrhosis, number and size of nodules, gross pattern, histological grade and variants, architectural pattern, invasion of large veins, and presence and location of extrahepatic metastases. The protein products of genes known to be involved in molecular pathogenesis of HCC, including epidermal growth factor receptor (EGFR), MET, keratin 19 (K19), vimentin, beta-catenin, mechanistic target of rapamycin (mTOR), extracellular signaling-related kinase (ERK)1, ERK2, Ki67, cyclin D1, caspase 3 and p53, were detected by immunohistochemistry on tissue microarrays. The expression levels were scored and statistically assessed for correlation with HCC parameters.

RESULTS: Infection with hepatitis C virus was identified in 49% of the 80 autopsy patients, cirrhosis in 90%, advanced tumors in 95%, and extrahepatic metastases in 38%. Expression of K19, p53 and ERK1 correlated to high-grade lesions. Expression of ERK1, nuclear beta-catenin, cyclin D1 and ERK2 correlated to higher rates of cell proliferation as determined by Ki67. Expression of MET, EGFR (> 0) and caspase 3 correlated with lower histological grades. Expression of EGFR correlated to that of caspase 3, and overexpression of EGFR (≥ 200/300) was observed in low-grade tumors more frequently (grades 1 and 2: 67% vs grade 3: 27% and grade 4: 30%). Expression of ERK1 was associated with that of K19 and vimentin, whereas expression of ERK2 was associated with that of cyclin D1, MET and membrane beta-catenin. Expression of vimentin was strongly correlated with that of K19.

CONCLUSION: Expression of K19, p53, ERK1, ERK2, vimentin and nuclear beta-catenin was related to higher-grade markers, as opposed to expression/overexpression of EGFR, MET and caspase 3.

Derivatives of Procaspase-Activating Compound 1 (PAC-1) and their Anticancer Activities

PAC-1 induces the activation of procaspase-3 in vitro and in cell culture by chelation of inhibitory labile zinc ions via its ortho-hydroxy-N-acylhydrazone moiety. First reported in 2006, PAC-1 has shown promise in cell culture and animal models of cancer, and a Phase I clinical trial in cancer patients began in March 2015 (NCT02355535). Because of the considerable interest in this compound and a well-defined structure-activity relationship, over 1000 PAC-1 derivatives have been synthesized in an effort to vary pharmacological properties such as potency and pharmacokinetics. This article provides a comprehensive examination of all PAC-1 derivatives reported to date. A survey of PAC-1 derivative libraries is provided, with an indepth discussion of four derivatives on which extensive studies have been performed.

Removal of Metabolic Liabilities Enables Development of Derivatives of Procaspase-Activating Compound 1 (PAC-1) with Improved Pharmacokinetics

Procaspase-activating compound 1 (PAC-1) is an o-hydroxy-N-acylhydrazone that induces apoptosis in cancer cells by chelation of labile inhibitory zinc from procaspase-3. PAC-1 has been assessed in a wide variety of cell culture experiments and in vivo models of cancer, with promising results, and a phase 1 clinical trial in cancer patients has been initiated (NCT02355535). For certain applications, however, the in vivo half-life of PAC-1 could be limiting. Thus, with the goal of developing a compound with enhanced metabolic stability, a series of PAC-1 analogues were designed containing modifications that systematically block sites of metabolic vulnerability. Evaluation of the library of compounds identified four potentially superior candidates with comparable anticancer activity in cell culture, enhanced metabolic stability in liver microsomes, and improved tolerability in mice. In head-to-head experiments with PAC-1, pharmacokinetic evaluation in mice demonstrated extended elimination half-lives and greater area under the curve values for each of the four compounds, suggesting them as promising candidates for further development.

Targeting procaspase-3 with WF-208, a novel PAC-1 derivative, causes selective cancer cell apoptosis

Caspase-3 is a critical effector caspase in apoptosis cascade, and is often over-expressed in many cancer tissues. The first synthesized procaspase-3 activator, PAC-1, induces cancer cell apoptosis and exhibits antitumour activity in murine xenograft models. To identify more potent procaspase-3 activators, a series of compounds were designed, synthesized and evaluated for their ability of inducing cancer cell death in culture. Among these compounds, WF-208 stood out by its high cytotoxicity against procaspase-3 overexpressed HL-60 cells. Compared with PAC-1, WF-208 showed higher cytotoxicity in cancer cells and lower toxicity in normal cells. The further investigation described herein showed that WF-208 activated procaspase-3, degraded IAPs (The Inhibitors of apoptosis proteins) and leaded to caspase-3-dependent cell death in tumour cells, which possibly because of the zinc-chelating properties. WF-208 also showed greater antitumour activity than PAC-1 in murine xenograft model. In conclusion, we have discovered WF-208 as a promising procaspase-3 activating compound, with higher activity and higher cell selectivity than PAC-1.

Synthesis and biological evaluation of benzothiazole derivatives bearing the ortho-hydroxy-N-acylhydrazone moiety as potent antitumor agents

A novel series of benzothiazole derivatives bearing the ortho-hydroxy-N-acylhydrazone moiety were designed, synthesized, and evaluated for their procaspase-3 kinase activation activities and antiproliferative activities against five cancer cell lines (NCI-H226, SK-N-SH, HT29, MKN-45, and MDA-MB-231). Most target compounds showed moderate to excellent cytotoxic activity against all five tested cancer lines. The most promising compound 18e (procaspase-3 EC50  = 0.31 µM) with IC50 values ranging from 0.24 to 0.92µM against all tested cell lines was 4.24-12.2 times more active than PAC-1 (procaspase-3 EC50  = 0.41 µM). Structure-activity relationship studies indicated that the phenyl group on the 2-hydroxyphenyl ring (moiety A) was critical for pharmacological activity in vitro. In addition, introduction of a benzyloxyl group on moiety A and a mono-electron-withdrawing group at the 4-position of the benzyloxyl group were more favorable for antitumor activity. Moreover, reduction of the electron density in the phenyl ring of the benzyloxy group led to a dramatic decrease in the procaspase-3 kinase activation activity.