Novel synthetic coumarins that targets NF-κB in Hepatocellular carcinoma

Noncoding RNAs as regulators of STAT3 pathway in gastrointestinal cancers: Roles in cancer progression and therapeutic response

Gastrointestinal (GI) tumors (cancers of the esophagus, gastric, liver, pancreas, colon, and rectum) contribute to a large number of deaths worldwide. STAT3 is an oncogenic transcription factor that promotes the transcription of genes associated with proliferation, antiapoptosis, survival, and metastasis. STAT3 is overactivated in many human malignancies including GI tumors which accelerates tumor progression, metastasis, and drug resistance. Research in recent years demonstrated that noncoding RNAs (ncRNAs) play a major role in the regulation of many signaling pathways including the STAT3 pathway. The major types of endogenous ncRNAs that are being extensively studied in oncology are microRNAs, long noncoding RNAs, and circular RNAs. These ncRNAs can either be tumor-promoters or tumor-suppressors and each one of them imparts their activity via different mechanisms. The STAT3 pathway is also tightly modulated by ncRNAs. In this article, we have elaborated on the tumor-promoting role of STAT3 signaling in GI tumors. Subsequently, we have comprehensively discussed the oncogenic as well as tumor suppressor functions and mechanism of action of ncRNAs that are known to modulate STAT3 signaling in GI cancers.

CXCR4 expression is elevated in TNBC patient derived samples and Z-guggulsterone abrogates tumor progression by targeting CXCL12/CXCR4 signaling axis in mice model

Environmental factors such as exposure to ionizing radiations, certain environmental pollutants, and toxic chemicals are considered as risk factors in the development of breast cancer. Triple-negative breast cancer (TNBC) is a molecular variant of breast cancer that lacks therapeutic targets such as progesterone receptor, estrogen receptor, and human epidermal growth factor receptor-2 which makes the targeted therapy ineffective in TNBC patients. Therefore, identification of new therapeutic targets for the treatment of TNBC and the discovery of new therapeutic agents is the need of the hour. In this study, CXCR4 was found to be highly expressed in majority of breast cancer tissues and metastatic lymph nodes derived from TNBC patients. CXCR4 expression is positively correlated with breast cancer metastasis and poor prognosis of TNBC patients suggesting that suppression of CXCR4 expression could be a good strategy in the treatment of TNBC patients. Therefore, the effect of Z-guggulsterone (ZGA) on the expression of CXCR4 in TNBC cells was examined. ZGA downregulated protein and mRNA expression of CXCR4 in TNBC cells and proteasome inhibition or lysosomal stabilization had no effect on the ZGA-induced CXCR4 reduction. CXCR4 is under the transcriptional control of NF-κB, whereas ZGA was found to downregulate transcriptional activity NF-κB. Functionally, ZGA downmodulated the CXCL12-driven migration/invasion in TNBC cells. Additionally, the effect of ZGA on growth of tumor was investigated in the orthotopic TNBC mice model and ZGA presented good inhibition of tumor growth and liver/lung metastasis in this model. Western blotting and immunohistochemical analysis indicated a reduction of CXCR4, NF-κB, and Ki67 in tumor tissues. Computational analysis suggested PXR agonism and FXR antagonism as targets of ZGA. In conclusion, CXCR4 was found to be overexpressed in majority of patient-derived TNBC tissues and ZGA abrogated the growth of TNBC tumors by partly targeting the CXCL12/CXCR4 signaling axis.

Discovery of Pyrimidine- and Coumarin-Linked Hybrid Molecules as Inducers of JNK Phosphorylation through ROS Generation in Breast Cancer Cells

Human epidermal growth factor receptor 2 (HER2)-positive breast cancer exhibits early relapses, poor prognoses, and high recurrence rates. Herein, a JNK-targeting compound has been developed that may be of utility in HER2-positive mammary carcinoma. The design of a pyrimidine-and coumarin-linked structure targeting JNK was explored and the lead structure PC-12 [4-(3-((2-((4-chlorobenzyl)thio) pyrimidin-4-yl)oxy)propoxy)-6-fluoro-2H-chromen-2-one (5d)] was observed to selectively inhibit the proliferation of HER2-positive BC cells. The compound PC-12 exerted DNA damage and induced apoptosis in HER-2 positive BC cells more significantly compared to HER-2 negative BC cells. PC-12 induced PARP cleavage and down-regulated the expression of IAP-1, BCL-2, SURVIVIN, and CYCLIN D1 in BC cells. In silico and theoretical calculations showed that PC-12 could interact with JNK, and in vitro studies demonstrated that it enhanced JNK phosphorylation through ROS generation. Overall, these findings will assist the discovery of new compounds targeting JNK for use in HER2-positive BC cells.

Therapeutic Effects of Coumarins with Different Substitution Patterns

The use of derivatives of natural and synthetic origin has gained attention because of their therapeutic effects against human diseases. Coumarins are one of the most common organic molecules and are used in medicine for their pharmacological and biological effects, such as anti-inflammatory, anticoagulant, antihypertensive, anticonvulsant, antioxidant, antimicrobial, and neuroprotective, among others. In addition, coumarin derivates can modulate signaling pathways that impact several cell processes. The objective of this review is to provide a narrative overview of the use of coumarin-derived compounds as potential therapeutic agents, as it has been shown that substituents on the basic core of coumarin have therapeutic effects against several human diseases and types of cancer, including breast, lung, colorectal, liver, and kidney cancer. In published studies, molecular docking has represented a powerful tool to evaluate and explain how these compounds selectively bind to proteins involved in various cellular processes, leading to specific interactions with a beneficial impact on human health. We also included studies that evaluated molecular interactions to identify potential biological targets with beneficial effects against human diseases.

Long non-coding RNAs (lncRNAs) in hepatocellular carcinoma progression: Biological functions and new therapeutic targets

Liver is an important organ in body that performs vital functions such as detoxification. Liver is susceptible to development of cancers, and hepatocellular carcinoma (HCC) is among them. 75-85% of liver cancer cases are related to HCC. Therefore, much attention has been directed towards understanding factors mediating HCC progression. LncRNAs are epigenetic factors with more than 200 nucleotides in length located in both nucleus and cytoplasm and they are promising candidates in cancer therapy. Directing studies towards understanding function of lncRNAs in HCC is of importance. LncRNAs regulate cell cycle progression and growth of HCC cells, and they can also induce/inhibit apoptosis in tumor cells. LncRNAs affect invasion and metastasis in HCC mainly by epithelial-mesenchymal transition (EMT) mechanism. Revealing the association between lncRNAs and downstream signaling pathways in HCC is discussed in the current manuscript. Infectious diseases can affect lncRNA expression in mediating HCC development and then, altered expression level of lncRNA is associated with drug resistance and radio-resistance. Biomarker application of lncRNAs and their role in prognosis and diagnosis of HCC are also discussed to pave the way for treatment of HCC patients.

Fangchinoline abrogates growth and survival of hepatocellular carcinoma by negative regulation of c-met/HGF and its associated downstream signaling pathways

Among all cancers, hepatocellular carcinoma (HCC) remains a lethal disease with limited treatment options. In this study, we have analyzed the possible inhibitory effects of Fangchinoline (FCN) on c-Met, a protein known to regulate the rapid phosphorylation of downstream signals, as well as mediate aberrant growth, metastasis, survival, and motility in cancer. FCN inhibited the activation of c-Met and its downstream signals PI3K, AKT, mTOR, MEK, and ERK under in vitro settings. Moreover, c-Met gene silencing lead to suppression of PI3K/AKT/mTOR and MEK/ERK signaling pathways, and induced apoptotic cell death upon exposure to FCN. In addition, FCN markedly inhibited the expression of the various oncogenic proteins such as Bcl-2/xl, survivin, IAP-1/2, cyclin D1, and COX-2. In vivo studies in HepG2 cells xenograft mouse model showed that FCN could significantly attenuate the tumor volume and weight, without affecting significant loss in the body weight. Similar to in vitro studies, expression level of c-Met and PI3K/AKT/mTOR, MEK/ERK signals was also suppressed by FCN in the tissues obtained from mice. Therefore, the novel findings of this study suggest that FCN can potentially function as a potent anticancer agent against HCC.

Development of 1-(4-(Substituted)piperazin-1-yl)-2-((2-((4-methoxybenzyl)thio)pyrimidin-4-yl)oxy)ethanones That Target Poly (ADP-Ribose) Polymerase in Human Breast Cancer Cells

A number of uracil amides cleave poly (ADP-ribose) polymerase and therefore novel thiouracil amide compounds were synthesized and screened for the loss of cell viability in a human-estrogen-receptor-positive breast cancer cell line. The synthesized compounds exhibited moderate to significant efficacy against human breast cancer cells, where the compound 5e IC₅₀ value was found to be 18 μM. Thouracil amide compounds 5a and 5e inhibited the catalytical activity of PARP1, enhanced cleavage of PARP1, enhanced phosphorylation of H2AX, and increased CASPASE 3/7 activity. Finally, in silico analysis demonstrated that compound 5e interacted with PARP1. Hence, specific thiouracil amides may serve as new drug-seeds for the development of PARP inhibitors for use in oncology.

Evaluation of Acute and Sub-Acute Toxicity Profile of 5-Methylcoumarin-4β-Glucoside in Mice

Vernonia glaberrima leaves are traditionally used to alleviate bodily pain, skin cancer, and other skin-related disorders. The purpose of the study was to investigate the acute and sub-acute toxicity of 5-methylcoumarin-4β-glucoside, a promising chemotherapeutic agent against colon cancer isolated from the leaves of Vernonia glaberrima. 5-methylcoumarin-4β-glucoside was isolated from the methanol leaf extract of Vernonia glaberrima following a previously described method. The acute toxicity study involved a two-phase 24 h observation for signs of mortality and toxicity following single oral dose administration of the isolated compound. For the sub-acute study, four groups of mice, averagely aged eight weeks, were administered graded doses of the compound (250, 500 and 1000 mg/kg) or vehicle for 28 days. On the 29th day, the mice were fasted, anesthetized, euthanized, then their blood and tissues were harvested for hematological, biochemical and histopathological evaluations. There were no signs of mortality or moribund status with an increasing dose of up to 5000 mg/kg over a 24 h period in the acute study. Also, there was no evidence of toxicity on the biochemical or hematopoietic systems in the sub-acute study (p < 0.05). At the dose of 1000 mg/kg, the mice showed some distorted histology with no corresponding alterations in serum biochemicals. Overall, the results showed that 5-methylcoumarin-4β-glucoside at dosages up to 500 mg/kg is tolerable in mice.

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5-methylcoumarin-4β-glucoside is a promising therapeutic agent against colon cancer.

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Acute toxicity study of the coumarine derivative gave an LD₅₀ above 5000 mg/kg.

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The compound demonstrated minimal histopathological toxicity at the highest dose.

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It also revealed no toxicity in sero-biochemical terms after a 28-day toxicity study.

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5-methylcoumarin-4β-glucoside is not toxic in mice at doses below 1000 mg/kg.

Advances in the site-selective C-5, C-3 and C-2 functionalization of chromones via sp2 C-H activation

In this work, site-selective C-H activation at C-5, C-3 and C-2 positions of chromones for the introduction of structural diversity to the chromone scaffold was studied. The keto group of the chromone moiety acts as the directing group for the selective functionalization of chromones at the C-5 position. Furthermore, the C-H functionalization at the electron-rich C-3 position of the chromone can be achieved using electrophilic coupling partners. The C-H functionalization at the C-2 position can be possible using nucleophilic coupling partners. The direct functionalization methods provide a better pathway for the generation of C-5, C-3 and C-2-substituted chromones with good atom economy than that of classical pre-functionalized reaction protocols.

3-Formylchromone Counteracts STAT3 Signaling Pathway by Elevating SHP-2 Expression in Hepatocellular Carcinoma

Simple Summary

STAT3 acts as a potential tumor-promoting transcription factor that gets aberrantly activated in several types of human cancers and plays a crucial role in tumor progression and metastasis. STAT3 expression has been correlated with a dismal prognosis and poor survival. In this study, we have demonstrated that 3-formylchromone inhibits the STAT3 signaling in HCC cells by modulating SHP-2 expression. It also effectively diminished the tumor growth and subsequent reduction in metastasis in the HCC mouse model without exhibiting any major side effects.

Abstract

Hepatocellular carcinoma (HCC) is one of the leading cancers that contribute to a large number of deaths throughout the globe. The signal transducer and activator of transcription 3 (STAT3) is a tumorigenic protein that is overactivated in several human malignancies including HCC. In the present report, the effect of 3-formylchromone (3FC) on the STAT3 signaling pathway in the HCC model was investigated. 3FC downregulated the constitutive phosphorylation of STAT3 and non-receptor tyrosine kinases such as JAK1 and JAK2. It also suppressed the transportation of STAT3 to the nucleus and reduced its DNA-binding ability. Pervanadate treatment overrode the 3FC-triggered STAT3 inhibition, and the profiling of cellular phosphatase expression revealed an increase in SHP-2 levels upon 3FC treatment. The siRNA-driven deletion of SHP-2 led to reinstate STAT3 activation. 3FC downmodulated the levels of various oncogenic proteins and decreased CXCL12-driven cell migration and invasion. Interestingly, 3FC did not exhibit any substantial toxicity, whereas it significantly regressed tumor growth in an orthotopic HCC mouse model and abrogated lung metastasis. Overall, 3FC can function as a potent agent that can display antitumor activity by targeting STAT3 signaling in HCC models.

Coumarins and Gastrointestinal Cancer: A New Therapeutic Option?

Cancers of the gastrointestinal (GI) tract are often life-threatening malignancies, which can be a severe burden to the health care system. Globally, the mortality rate from gastrointestinal tumors has been increasing due to the lack of adequate diagnostic, prognostic, and therapeutic measures to combat these tumors. Coumarin is a natural product with remarkable antitumor activity, and it is widely found in various natural plant sources. Researchers have explored coumarin and its related derivatives to investigate their antitumor activity, and the potential molecular mechanisms involved. These mechanisms include hormone antagonists, alkylating agents, inhibitors of angiogenesis, inhibitors of topoisomerase, inducers of apoptosis, agents with antimitotic activity, telomerase inhibitors, inhibitors of human carbonic anhydrase, as well as other potential mechanisms. Consequently, drug design and discovery scientists and medicinal chemists have collaborated to identify new coumarin-related agents in order to produce more effective antitumor drugs against GI cancers. Herein, we summarize the therapeutic effects of coumarin and its derivatives against GI cancer.

Computer-Aided Drug Design Applied to Secondary Metabolites as Anticancer Agents

Computer-Aided Drug Design (CADD) techniques have garnered a great deal of attention in academia and industry because of their great versatility, low costs, possibilities of cost reduction in in vitro screening and in the development of synthetic steps; these techniques are compared with highthroughput screening, in particular for candidate drugs. The secondary metabolism of plants and other organisms provide substantial amounts of new chemical structures, many of which have numerous biological and pharmacological properties for virtually every existing disease, including cancer. In oncology, compounds such as vimblastine, vincristine, taxol, podophyllotoxin, captothecin and cytarabine are examples of how important natural products enhance the cancer-fighting therapeutic arsenal. In this context, this review presents an update of Ligand-Based Drug Design and Structure-Based Drug Design techniques applied to flavonoids, alkaloids and coumarins in the search of new compounds or fragments that can be used in oncology. A systematical search using various databases was performed. The search was limited to articles published in the last 10 years. The great diversity of chemical structures (coumarin, flavonoids and alkaloids) with cancer properties, associated with infinite synthetic possibilities for obtaining analogous compounds, creates a huge chemical environment with potential to be explored, and creates a major difficulty, for screening studies to select compounds with more promising activity for a selected target. CADD techniques appear to be the least expensive and most efficient alternatives to perform virtual screening studies, aiming to selected compounds with better activity profiles and better "drugability".

Regulation of Nuclear Factor-KappaB (NF-κB) signaling pathway by non-coding RNAs in cancer: Inhibiting or promoting carcinogenesis?

The nuclear factor-kappaB (NF-κB) signaling pathway is considered as a potential therapeutic target in cancer therapy. It has been well established that transcription factor NF-κB is involved in regulating physiological and pathological events including inflammation, immune response and differentiation. Increasing evidences suggest that deregulated NF-κB signaling can enhance cancer cell proliferation, metastasis and also mediate radio-as well as chemo-resistance. On the contrary, non-coding RNAs (ncRNAs) have been found to modulate NF-κB signaling pathway under different settings. MicroRNAs (miRNAs) can dually inhibit/induce NF-κB signaling thereby affecting the growth and migration of cancer cells. Furthermore, the response of cancer cells to radiotherapy and chemotherapy may also be regulated by miRNAs. Regulation of NF-κB by miRNAs may be mediated via binding to 3^/-UTR region. Interestingly, anti-tumor compounds can increase the expression of tumor-suppressor miRNAs in inhibiting NF-κB activation and the progression of cancers. Long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) can also effectively modulate NF-κB signaling thus affecting tumorigenesis. It is noteworthy that several studies have demonstrated that lncRNAs and circRNAs can affect miRNAs in targeting NF-κB activation. They can act as competing endogenous RNA (ceRNA) thereby reducing miRNA expression to induce NF-κB activation that can in turn promote cancer progression and malignancy.

Autophagy Promotes Cigarette Smoke-Initiated and Elastin-Driven Bronchitis-Like Airway Inflammation in Mice

Cigarette smoke (CS)-induced macrophage activation and airway epithelial injury are both critical for the development of chronic obstructive pulmonary disease (COPD), while the eventual functions of autophagy in these processes remain controversial. We have recently developed a novel COPD mouse model which is based on the autoimmune response sensitized by CS and facilitated by elastin. In the current study, we therefore utilized this model to investigate the roles of autophagy in different stages of the development of bronchitis-like airway inflammation. Autophagic markers were increased in airway epithelium and lung tissues, and Becn+/- or Lc3b-/- mice exhibited reduced neutrophilic airway inflammation and mucus hyperproduction in this COPD mouse model. Moreover, treatment of an autophagic inhibitor 3-methyladenine (3-MA) either during CS-initiated sensitization or during elastin provocation significantly inhibited the bronchitis-like phenotypes in mice. Short CS exposure rapidly induced expression of matrix metallopeptidase 12 (MMP12) in alveolar macrophages, and treatment of doxycycline, a pan metalloproteinase inhibitor, during CS exposure effectively attenuated the ensuing elastin-induced airway inflammation in mice. CS extract triggered MMP12 expression in cultured macrophages, which was attenuated by autophagy impairment (Becn+/- or Lc3b-/-) or inhibition (3-MA or Spautin-1). These data, taken together, demonstrate that autophagy mediates both the CS-initiated MMP12 activation in macrophages and subsequent airway epithelial injury, eventually contributing to development COPD-like airway inflammation. This study reemphasizes that inhibition of autophagy as a novel therapeutic strategy for CS-induced COPD.

Cytochrome P450 1A2 overcomes nuclear factor kappa B-mediated sorafenib resistance in hepatocellular carcinoma

Sorafenib resistance has become the main obstacle in the effective treatment of advanced hepatocellular carcinoma (HCC) patients. Activation of nuclear factor kappa B (NF-κB) is a newly identified mechanism that contributes to desensitized sorafenib. Cytochrome P450 1A2 (CYP1A2) functions as a tumor suppressor in HCC and its expression is negatively associated with NF-κB in the liver. This study aimed to study whether CYP1A2 could overcome sorafenib resistance. To investigate whether CYP1A2 and NF-κB p65 played roles in sorafenib desensitization, we established sorafenib-resistant (SR) HCC cells. SR cells decreased the expression of CYP1A2 along with the upregulation of NF-κB p65. CYP1A2 overexpression attenuated SR cell proliferation, increased sorafenib sensitivity, and inhibited the NF-κB pathway, whereas CYP1A2 silence showed opposite effects. Sorafenib, in combination with omeprazole, a CYP1A2 inducer, significantly hindered the growth and invasion of SR cells in vitro as well as decreased the tumor growth in vivo. The combination treatment markedly increased CYP1A2 expression and inhibited the sorafenib-induced NF-κB signaling. In addition, the overexpression of NF-κB p65 stimulated the SR cell growth and desensitized sorafenib in SR cells, where CYP1A2 overexpression reversed the phenomenon. Lastly, the majority of HCC tissue samples displayed decreased CYP1A2 but increased NF-κB p65 protein expression. Collectively, CYP1A2 can sensitize SR cells to sorafenib via inhibiting NF-κB p65 axis. Omeprazole in combination with sorafenib exerts a synergistic effect in alleviating acquired sorafenib resistance.

Anti-neoplastic Effect of Ginkgolide C through Modulating c-Met Phosphorylation in Hepatocellular Carcinoma Cells

Ginkgolide C (GGC) derived from Ginkgo biloba, has been reported to exhibit various biological functions. However, the anti-neoplastic effect of GGC and its mechanisms in liver cancer have not been studied previously. Hepatocyte growth factor (HGF)/c-mesenchymal-epithelial transition receptor (c-Met) pathway can regulate tumor growth and metastasis in hepatocellular carcinoma (HCC) cells. This study aimed to evaluate the anti-neoplastic effect of GGC against HCC cells and we observed that GGC inhibited HGF-induced c-Met and c-Met downstream oncogenic pathways, such as PI3K/Akt/mTOR and MEK/ERK. In addition, GGC also suppressed the proliferation of expression of diverse tumorigenic proteins (Bcl-2, Bcl-xL, Survivin, IAP-1, IAP-2, Cyclin D1, and COX-2) and induced apoptosis. Interestingly, the silencing of c-Met by small interfering RNA (siRNA) mitigated c-Met expression and enhanced GGC-induced apoptosis. Moreover, it was noted that GGC also significantly reduced the invasion and migration of HCC cells. Overall, the data clearly demonstrate that GGC exerts its anti-neoplastic activity through modulating c-Met phosphorylation and may be used as an effective therapy against HCC.

Effects of taraxasterol against ethanol and high-fat diet-induced liver injury by regulating TLR4/MyD88/NF-κB and Nrf2/HO-1 signaling pathways

Studies have reported that taraxasterol (TAR) is effective in the treatment of immune liver injury and alcoholic liver injury. The mechanism of action is mainly related to the inhibition of inflammation. To determine the key molecular mechanisms for the effect of TAR on alleviating ethanol and high-fat diet-induced liver injury, pathological morphology, biochemistry, oxidative stress, inflammatory response and lipid metabolism were examined. Our results showed that TAR could inhibit ethanol-induced hepatocyte death or lipid accumulation, and suppress oxidative stress, inflammatory response and lipid metabolism disorders. More specifically, ethanol-induced TLR-4 and MyD88 inflammatory response were down-regulated, when treated with TAR. Production of CYP2E1, Nrf2 and HO-1, which produced in response to increased oxidative stress, were regulated in TAR treated, ethanol-induced hepatocytes. In summary, TAR could inhibit the inflammatory response and oxidative stress, which was related to the regulation of TAR on TLR-4/MyD88/NF-κB and Nrf2/HO-1 pathways.

A QSAR Study on the 4-Substituted Coumarins as Potent Tubulin Polymerization Inhibitors

Purpose: Despite the discovery and synthesis of several anticancer drugs, cancer is still a major life threatening incident for human beings after cardiovascular diseases. Toxicity, severe side effects, and drug resistance are serious problems of available commercial anticancer drugs. Coumarins are synthetic and natural heterocycles that show promising antiproliferative activities against various tumors. The aim of this research is to computationally study the coumarin derivatives in order to develop reliable quantitative structure-activity relationship (QSAR) models for predicting their anticancer activities.

Methods: A data set of thirty one coumarin analogs with significant antiproliferative activities toward HepG2 cells were selected from the literature. The molecular descriptors for these compounds were calculated using Dragon, HyperChem, and ACD/Labs programs. Genetic algorithm (GA) accompanied by multiple linear regression (MLR) for simultaneous feature selection and model development was employed for generating the QSAR models.

Results: Based on the obtained results, the developed linear QSAR models with three and four descriptors showed good predictive power with r2 values of 0.670 and 0.692, respectively. Moreover, the calculated validation parameters for the models confirmed the reliability of the QSAR models.

Conclusion: The findings of the current study could be useful for the design and synthesis of novel anticancer drugs based on coumarin structure.

Allelochemical Activity of Eugenol-Derived Coumarins on Lactuca sativa L

Coumarins are widely distributed substances in plant species that promote phytotoxic effects, allowing them to be exploited as herbicides less harmful to the environment, since many invasive species have demonstrated resistance to commercially available products. The derived coumarins used in this study had not been tested in plant models and their effect on plants was unknown. The objective of this study was to evaluate the phytotoxic action of these coumarins in bioassays with Lactuca sativa L., in order to select the most responsive substance whose toxicity was best elucidated by chromosomal complement and enzymatic antioxidant metabolism studies. From the phytotoxicity assays, coumarin 8-methoxy-2-oxo-6-(prop-2-en-1-yl)-2H-chromene-3-carboxylic acid (A1), reported here for the first time, was selected as the most responsive and caused a reduction in the following parameters: number of normal seedlings, fresh biomass, root length and shoot length. Subsequent studies demonstrated that this coumarin is cytogenotoxic due to damage caused to the cell cycle and the occurrence of chromosomal abnormalities. However, it did not interfere with antioxidant enzyme activity and did not cause lipid peroxidation. The changes caused by coumarin A1 described herein can contribute to better understanding the allelochemical actions of coumarins and the potential use of these substances in the production of natural herbicides.

Identification of a novel 1,2 oxazine that can induce apoptosis by targeting NF-κB in hepatocellular carcinoma cells

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10 new 1,2-Oxazines were synthesized and evaluated for their anticancer activity.

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3i is lead cytotoxic agent which increased SubG1 cell population of HCC cells.

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p65 siRNA transfection significantly reduced the 3i induced DNA fragmentation.

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3i decreased DNA binding and NF-κB-dependent luciferase reporter gene expression.

Constitutive activation of NF-κB is associated with proinflammatory diseases and suppression of the NF-κB signaling pathway has been considered as an effective therapeutic strategy in the treatment of various cancers including hepatocellular carcinoma (HCC). Herein, we report the synthesis of 1,2 oxazines and their anticancer potential. The antiproliferative studies presented 3-((4-(1H-benzo[d]imidazol-2-yl)piperidin-1-yl)methyl)-4-phenyl-4,4a,5,6,7,7a-hexahydrocyclopenta [e][1,2]oxazine(3i) as a lead cytotoxic agent against HCC cells. Flow cytometric analysis showed that 3i caused a substantial increase in the subG1 cell population. Annexin-V-FITC-PI staining showed a significant increase in the percentage of apoptotic cells on treatment with 3i. Transfection with p65 siRNA significantly reduced the 3i induced DNA fragmentation indicating that 3i may primarily mediate its proapoptotic effects by abrogating the NF-κB signaling. In addition, treatment of HCC cells with 3i decreased the DNA binding ability of NF-κB and NF-κB-dependent luciferase expression. Taken together, this report introduces 1,2-oxazine that potently targets the NF-κB signaling pathway in HCC cells.

The IκB Kinase Inhibitor ACHP Targets the STAT3 Signaling Pathway in Human Non-Small Cell Lung Carcinoma Cells

STAT3 is an oncogenic transcription factor that regulates the expression of genes which are involved in malignant transformation. Aberrant activation of STAT3 has been observed in a wide range of human malignancies and its role in negative prognosis is well-documented. In this report, we performed high-throughput virtual screening in search of STAT3 signaling inhibitors using a cheminformatics platform and identified 2-Amino-6-[2-(Cyclopropylmethoxy)-6-Hydroxyphenyl]-4-Piperidin-4-yl Nicotinonitrile (ACHP) as the inhibitor of the STAT3 signaling pathway. The predicted hit was evaluated in non-small cell lung cancer (NSCLC) cell lines for its STAT3 inhibitory activity. In vitro experiments suggested that ACHP decreased the cell viability and inhibited the phosphorylation of STAT3 on Tyr705 of NSCLC cells. In addition, ACHP imparted inhibitory activity on the constitutive activation of upstream protein tyrosine kinases, including JAK1, JAK2, and Src. ACHP decreased the nuclear translocation of STAT3 and downregulated its DNA binding ability. Apoptosis was evidenced by cleavage of caspase-3 and PARP with the subsequent decline in antiapoptotic proteins, including Bcl-2, Bcl-xl, and survivin. Overall, we report that ACHP can act as a potent STAT3 signaling inhibitor in NSCLC cell lines.

TIPE2 Induced the Proliferation, Survival, and Migration of Lung Cancer Cells Through Modulation of Akt/mTOR/NF-κB Signaling Cascade

Lung cancer represents the most common cause of cancer deaths in the world, constituting around 11.6% of all new cancer cases and 18.4% of cancer-related deaths. The propensity for early spread, lack of suitable biomarkers for early diagnosis, as well as prognosis and ineffective existing therapies, contribute to the poor survival rate of lung cancer. Therefore, there is an urgent need to develop novel biomarkers for early diagnosis and prognosis which in turn can facilitate newer therapeutic avenues for the management of this aggressive neoplasm. TIPE2 (tumor necrosis factor-α-induced protein 8-like 2), a recently identified cytoplasmic protein, possesses enormous potential in this regard. Immunohistochemical analysis showed that TIPE2 was significantly upregulated in different stages and grades of lung cancer tissues compared to normal lung tissues, implying its involvement in the positive regulation of lung cancer. Further, knockout of TIPE2 resulted in significantly reduced proliferation, survival, and migration of human lung cancer cells through modulation of the Akt/mTOR/NF-κB signaling axis. In addition, knockout of TIPE2 also caused arrest in the S phase of the cell cycle of lung cancer cells. As tobacco is the most predominant risk factor for lung cancer, we therefore evaluated the effect of TIPE2 in tobacco-mediated lung carcinogenesis as well. Our results showed that TIPE2 was involved in nicotine-, nicotine-derived nitrosamine ketone (NNK)-, N-nitrosonornicotine (NNN)-, and benzo[a]pyrene (BaP)-mediated lung cancer through inhibited proliferation, survival, and migration via modulation of nuclear factor kappa B (NF-κB)- and NF-κB-regulated gene products, which are involved in the regulation of diverse processes in lung cancer cells. Taken together, TIPE2 possesses an important role in the development and progression of lung cancer, particularly in tobacco-promoted lung cancer, and hence, specific targeting of it holds an enormous prospect in newer therapeutic interventions in lung cancer. However, these findings need to be validated in the in vivo and clinical settings to fully establish the diagnostic and prognostic importance of TIPE2 against lung cancer.

Antiangiogenic Effects of Coumarins against Cancer: From Chemistry to Medicine

Angiogenesis, the process of formation and recruitment of new blood vessels from pre-existing vessels, plays an important role in the development of cancer. Therefore, the use of antiangiogenic agents is one of the most critical strategies for the treatment of cancer. In addition, the complexity of cancer pathogenicity raises the need for multi-targeting agents. Coumarins are multi-targeting natural agents belonging to the class of benzopyrones. Coumarins have several biological and pharmacological effects, including antimicrobial, antioxidant, anti-inflammation, anticoagulant, anxiolytic, analgesic, and anticancer properties. Several reports have shown that the anticancer effect of coumarins and their derivatives are mediated through targeting angiogenesis by modulating the functions of vascular endothelial growth factor as well as vascular endothelial growth factor receptor 2, which are involved in cancer pathogenesis. In the present review, we focus on the antiangiogenic effects of coumarins and related structure-activity relationships with particular emphasis on cancer.

N-Substituted Pyrido-1,4-Oxazin-3-Ones Induce Apoptosis of Hepatocellular Carcinoma Cells by Targeting NF-κB Signaling Pathway

Hepatocellular carcinoma (HCC) is a fatal disease and ranked fifth in cancer related mortality. Persistent activation of NF-κB is responsible for the oncogenesis, metastasis, tumor evasion, anti-apoptosis, angiogenesis and proliferation in HCC. Therefore, designing of chemically novel, biologically potent small molecules that target NF-κB signaling cascade have gained prominent clinical interest. Herein we synthesized a novel class of 4-(substituted)-2H-pyrido[3,2-b][1,4]oxazin-3(4H)-one by reacting 2H-pyrido[3,2-b][1,4]oxazin-3(4H)-one with various alkyl halides by using combustion derived bismuth oxide. We evaluated the antiproliferative efficacy of newly synthesized compounds against HCC cells and identified 4-(4-nitrobenzyl)-2H-pyrido[3,2-b][1,4]oxazin-3(4H)-one (NPO) as lead anticancer agent. In addition, we investigated the effect of NPO on the DNA binding ability of NF-κB and NF-κB regulated luciferase expression in HCC cells. The results demonstrated that NPO can induce significant growth inhibitory effects in HepG2, HCCLM3 and Huh-7 cells in dose and time-dependent manner. Interestingly, NPO induced significant downregulation in p65 DNA binding ability, p65 phosphorylation and subsequent expression of NF-κB dependent luciferase gene expression in diverse HCC cell lines. Further, in silico docking analysis suggested that NPO can show direct physical interaction with NF-κB. Finally, NPO was found to significantly abrogate tumor growth at a dose of 50 mg/kg in an orthotopic mouse model. Thus, we report the potential anticancer effects of NPO as a novel inhibitor of NF-κB signaling pathway in HCC.

Targeting DNA Binding for NF-κB as an Anticancer Approach in Hepatocellular Carcinoma

Quinoline core has been shown to possess a promising role in the development of anticancer agents. However, the correlation between its broad spectrum of bioactivity and the underlying mechanism of actions is poorly understood. The present study, with the use of bioinformatics approaches, reported a series of designed molecules which integrated quinoline core and sulfonyl moiety, with the objective of evaluating the substituent and linker effects on anticancer activities and associated mechanistic targets. We identified potent compounds (1h, 2h, 5 and 8) exhibiting significant anticancer effects towards liver cancer cells (Hep3B) with the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) relative values of cytotoxicity below 0.40, a value in the range of doxorubicin positive control with the value of 0.12. Bulky substituents and the presence of bromine atom, as well as the presence of sulfonamide linkage, are likely the favorable structural components for molecules exerting a strong anticancer effect. To the best of our knowledge, our findings obtained from chemical synthesis, in vitro cytotoxicity, bioinformatics-based molecular docking analysis (similarity ensemble approach, SEA),and electrophoretic mobility shift assay provided the first evidence in correlation to the anticancer activities of the selected compound 5 with the modulation on the binding of transcription factor NF-κB to its target DNA. Accordingly, compound 5 represented a lead structure for the development of quinoline-based NF-κB inhibitors and this work added novel information on the understanding of the mechanism of action for bioactive sulfonyl-containing quinoline compounds against hepatocellular carcinoma.

Evidence for the Involvement of the Master Transcription Factor NF-κB in Cancer Initiation and Progression

Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is responsible for the regulation of a large number of genes that are involved in important physiological processes, including survival, inflammation, and immune responses. At the same time, this transcription factor can control the expression of a plethora of genes that promote tumor cell proliferation, survival, metastasis, inflammation, invasion, and angiogenesis. The aberrant activation of this transcription factor has been observed in several types of cancer and is known to contribute to aggressive tumor growth and resistance to therapeutic treatment. Although NF-κB has been identified to be a major contributor to cancer initiation and development, there is evidence revealing its role in tumor suppression. This review briefly highlights the major mechanisms of NF-κB activation, the role of NF-κB in tumor promotion and suppression, as well as a few important pharmacological strategies that have been developed to modulate NF-κB function.

Endophytic Fungi-Alternative Sources of Cytotoxic Compounds: A Review

Cancer is a major cause of death worldwide, with an increasing number of cases being reported annually. The elevated rate of mortality necessitates a global challenge to explore newer sources of anticancer drugs. Recent advancements in cancer treatment involve the discovery and development of new and improved chemotherapeutics derived from natural or synthetic sources. Natural sources offer the potential of finding new structural classes with unique bioactivities for cancer therapy. Endophytic fungi represent a rich source of bioactive metabolites that can be manipulated to produce desirable novel analogs for chemotherapy. This review offers a current and integrative account of clinically used anticancer drugs such as taxol, podophyllotoxin, camptothecin, and vinca alkaloids in terms of their mechanism of action, isolation from endophytic fungi and their characterization, yield obtained, and fungal strain improvement strategies. It also covers recent literature on endophytic fungal metabolites from terrestrial, mangrove, and marine sources as potential anticancer agents and emphasizes the findings for cytotoxic bioactive compounds tested against specific cancer cell lines.

Novel 1,3,4-Oxadiazole Induces Anticancer Activity by Targeting NF-κB in Hepatocellular Carcinoma Cells

Aberrant activation of NF-κB is linked with the progression of human malignancies including hepatocellular carcinoma (HCC), and blockade of NF-κB signaling could be a potential target in the treatment of several cancers. Therefore, designing of novel small molecule inhibitors that target NF-κB activation is of prime importance in the treatment of several cancers. In the present work, we report the synthesis of series of 1,3,4-oxadiazoles, investigated their anticancer potential against HCC cells, and identified 2-(3-chlorobenzo[b]thiophen-2-yl)-5-(3-methoxyphenyl)-1,3,4-oxadiazole (CMO) as the lead compound. Further, we examined the effect of CMO on cell cycle distribution (flow cytometry), apoptosis (annexin V-propidium iodide-FITC staining), and phosphorylation of NF-κB signaling pathway proteins (IκB and p65) in HCC cells. We found that CMO induced antiproliferative effect in dose- and time-dependent manner. Also, CMO significantly increased the percentage of sub-G1 cell population and induced apoptosis. Furthermore, CMO found to decrease the phosphorylation of IκB (Ser 32) in the cytoplasmic extract and p65 (Ser 536) in the nuclear extract of HCC cells. It also abrogated the DNA binding ability and transcriptional activity of NF-κB. CMO induced the cleavage of PARP and caspase-3 in a time-dependent manner. In addition, transfection with p65 small interfering RNA blocks CMO-induced caspase-3/7 activation. Molecular docking analysis revealed that CMO interacts with the hydrophobic region of p65 protein. Thus, we are reporting CMO as an inhibitor of NF-κB signaling pathway.

Identification of Novel Class of Triazolo-Thiadiazoles as Potent Inhibitors of Human Heparanase and their Anticancer Activity

Background

Expression and activity of heparanase, an endoglycosidase that cleaves heparan sulfate (HS) side chains of proteoglycans, is associated with progression and poor prognosis of many cancers which makes it an attractive drug target in cancer therapeutics.

Methods

In the present work, we report the in vitro screening of a library of 150 small molecules with the scaffold bearing quinolones, oxazines, benzoxazines, isoxazoli(di)nes, pyrimidinones, quinolines, benzoxazines, and 4-thiazolidinones, thiadiazolo[3,2-a]pyrimidin-5-one, 1,2,4-triazolo-1,3,4-thiadiazoles, and azaspiranes against the enzymatic activity of human heparanase. The identified lead compounds were evaluated for their heparanase-inhibiting activity using sulfate [³⁵S] labeled extracellular matrix (ECM) deposited by cultured endothelial cells. Further, anti-invasive efficacy of lead compound was evaluated against hepatocellular carcinoma (HepG2) and Lewis lung carcinoma (LLC) cells.

Results

Among the 150 compounds screened, we identified 1,2,4-triazolo-1,3,4-thiadiazoles bearing compounds to possess human heparanase inhibitory activity. Further analysis revealed 2,4-Diiodo-6-(3-phenyl-[1, 2, 4]triazolo[3,4-b][1, 3, 4]thiadiazol-6yl)phenol (DTP) as the most potent inhibitor of heparanase enzymatic activity among the tested compounds. The inhibitory efficacy was demonstrated by a colorimetric assay and further validated by measuring the release of radioactive heparan sulfate degradation fragments from [³⁵S] labeled extracellular matrix. Additionally, lead compound significantly suppressed migration and invasion of LLC and HepG2 cells with IC₅₀ value of ~5 μM. Furthermore, molecular docking analysis revealed a favourable interaction of triazolo-thiadiazole backbone with Asn-224 and Asp-62 of the enzyme.

Conclusions

Overall, we identified biologically active heparanase inhibitor which could serve as a lead structure in developing compounds that target heparanase in cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3214-8) contains supplementary material, which is available to authorized users.

Synthesis, molecular modeling and anticancer activity of new coumarin containing compounds

A series of new coumarin containing compounds were synthesized from 4-bromomethylcoumarin derivatives 2a, b and different heteroaromatic systems 4a-e, 6a-d, 8, 10via methylene thiolinker. Twenty-four compounds were screened biologically against two human tumor cell lines, breast carcinoma MCF-7 and hepatocellular carcinoma HePG-2, at the national cancer institute, Cairo, Egypt using 5-fluorouracil as standard drug. Compounds 5h, 7d, 7h, 9a, 13a and 13d showed strong activity against both MCF-7 and HepG-2 cell lines with being compound 13a is the most active with IC₅₀ values of 5.5 µg/ml and 6.9 µg/ml respectively. Docking was performed with protein 1KE9 to study the binding mode of the designed compounds.

Deoxyelephantopin induces apoptosis in HepG2 cells via oxidative stress, NF-κB inhibition and mitochondrial dysfunction

Deoxyelephantopin (DET), a naturally occurring sesquiterpene lactone present in Chinese medicinal herb, Elephantopus scaber has been shown to exert anti-inflammatory as well as anticancer effects in various cancer cells of human origin in vitro. However, the exact molecular mechanism underlying DET-induced apoptosis remains largely unexplored, particularly in human hepatocellular carcinoma G2 (HepG2) cells. In the present study, we found that DET inhibits proliferation and induces apoptosis in HepG2 cells in a dose-dependent manner. This DET-mediated apoptosis was found to be associated with reactive oxygen species generation, glutathione depletion and decreased activity of thioredoxin reductase, mitochondrial membrane potential disruption, Bcl-2 family proteins modulation, cytochrome c release, caspases-3 activation, PARP cleavage and inhibition of NF-κB activation. DET inhibited the constitutive as well as induced-translocation of NF-κB into nucleus and augmented the apoptotic effect of Gemcitabine. IKK-16 (NF-κB inhibitor) further enhanced the cytotoxicity of DET and gemcitabine indicating that DET induces apoptosis in HepG2 cells at least partially through inhibition of NF-κB activation. Further mechanistic study demonstrated that DET inhibits the translocation of constitutive as well as induced-NF-κB into nucleus by decreasing phosphorylation of IкBα. Moreover, pretreatment of cells with 3 mM NAC reversed DET-mediated cell death and NF-κB inhibition, indicating that DET exerts its anticancer effects mainly through oxidative stress. Therefore, DET may be developed into a lead chemotherapeutic drug as a single agent or in combination with clinical drugs for the effective treatment of liver cancer. © 2016 BioFactors, 43(1):63-72, 2017.

Novel Synthetic Oxazines Target NF-κB in Colon Cancer In Vitro and Inflammatory Bowel Disease In Vivo

Aberrant activation of nuclear factor kappa B (NF-κB) has been linked with the pathogenesis of several proinflammatory diseases including number of cancers and inflammatory bowel diseases. In the present work, we evaluated the anticancer activity of 1,2-oxazines derivatives against colorectal cancer cell lines and identified 2-((2-acetyl-6,6-dimethyl-4-phenyl-5,6-dihydro-2H-1,2-oxazin-3-yl)methyl)isoindoline-1,3-dione (API) as the lead anticancer agent among the tested compounds. The apoptosis inducing effect of API was demonstrated using flow cytometry analysis and measuring the caspase 3/7 activity in API treated cells. Based on the literature on inhibition of NF-κB by oxazines, we evaluated the effect of 1,2-oxazines against the ability of NF-κB binding to DNA, NF-κB-dependent luciferase expression and IκBα phosphorylation. We found that, API abrogate constitutive activation of NF-κB and inhibits IκBα phosphorylation in HCT116 cells. Our in silico analysis revealed the binding of oxazines to the hydrophobic cavity that present between the interface of p65 and IκBα. Given the relevance with aberrant activation of NF-κB in inflammation bowel disease (IBD), we evaluated the effect of API on dextran sulphate sodium-induced IBD mice model. The treatment of IBD induced mice with API decreased the myeloperoxidase activity in colonic extract, modulated the colon length and serum levels of pro- and anti-inflammatory cytokines such as TNF-α, IFN-γ, IL-6, IL-1β and IL-10. Furthermore, the histological analysis revealed the restoration of the distorted cryptic epithelial structure of colon in the API treated animals. In conclusion, we comprehensively validated the NF-κB inhibitory efficacy of API that targets NF-κB in in vitro colon cancer and an in vivo inflammatory bowel disease model.

Synthesis, characterization and in vitro evaluation of novel enantiomerically-pure sulphonamide antimalarials

Malaria parasites are currently gaining drug-resistance rapidly, across countries and continents. Hence, the discovery and development of novel chemical scaffolds, with superior antimalarial activity remain an important priority, for the developing world. Our report describes the development, characterization and evaluation of novel bepotastine-based sulphonamide antimalarials inhibiting asexual stage development of Plasmodium falciparum parasites in vitro. The screening results showed potent inhibitory activity of a number of novel sulphonamides against P. falciparum at low micromolar concentrations, in particular in late-stage parasite development. Based on computational studies we hypothesize N-myristoyltransferase as the target of the compounds developed here. Our results demonstrate the value of novel bepotastine-based sulphonamide compounds for targeting the asexual developmental stages of P. falciparum.

Triptolide Inhibits Invasion and Tumorigenesis of Hepatocellular Carcinoma MHCC-97H Cells Through NF-κB Signaling

BACKGROUND We investigated whether the plant-derived agent triptolide (TPL) could effectively inhibit the growth and invasion of human hepatocellular carcinoma (HCC) cells. MATERIAL AND METHODS MHCC-97H cells were treated with various concentration of TPL for various times. To detect the effect of NF-κB on TPL-induced signal pathways, MHCC-97H cells were transfected with p65 siRNA or p65 cDNA, then treated with TPL. We detected cell survival and apoptosis by MTT, soft-agar colony formation assay, flow cytometry, and TUNEL assay. Cell migration and invasion was determined by Matrigel invasion and a wound-healing assay. NF-κB activity was detected by electrophoretic mobility shift assay (EMSA); MMP-9 activity was detected by ELISA. Western blot and real-time PCR (RT-PCR) assays were used to detect p65 and MMP-9 protein and mRNA expression. A subcutaneously implanted tumor model of MHCC-97H cells in nude mice was used to assess the effects of TPL on tumorigenesis in vivo. RESULTS We showed that TPL treatment significantly suppressed growth and induced apoptosis of MHCC-97H cells in a dose- and time-dependent manner in vitro. Furthermore, TPL treatment inhibited invasion in vitro and inhibited the growth and lung metastasis of MHCC-97H cells in vivo. NF-κB and MMP-9 were inactivated with TPL treatment. Overexpression of p65 restored MMP-9 activity and inhibited the TPL anti-tumor effect on MHCC-97H cells. Knockdown of p65 blocked MMP-9 activation and enhanced TPL-induced cell apoptosis and survival inhibition, and TPL inhibition of migration and invasion in vitro. CONCLUSIONS TPL treatment inhibited MHCC-97H cell growth, invasion, and metastasis in vitro and vivo, suggesting that TPL could be developed as a potential therapeutic agent for the treatment of HCC.

Trisubstituted-Imidazoles Induce Apoptosis in Human Breast Cancer Cells by Targeting the Oncogenic PI3K/Akt/mTOR Signaling Pathway

Overactivation of PI3K/Akt/mTOR is linked with carcinogenesis and serves a potential molecular therapeutic target in treatment of various cancers. Herein, we report the synthesis of trisubstituted-imidazoles and identified 2-chloro-3-(4, 5-diphenyl-1H-imidazol-2-yl) pyridine (CIP) as lead cytotoxic agent. Naïve Base classifier model of in silico target prediction revealed that CIP targets RAC-beta serine/threonine-protein kinase which comprises the Akt. Furthermore, CIP downregulated the phosphorylation of Akt, PDK and mTOR proteins and decreased expression of cyclin D1, Bcl-2, survivin, VEGF, procaspase-3 and increased cleavage of PARP. In addition, CIP significantly downregulated the CXCL12 induced motility of breast cancer cells and molecular docking calculations revealed that all compounds bind to Akt2 kinase with high docking scores compared to the library of previously reported Akt2 inhibitors. In summary, we report the synthesis and biological evaluation of imidazoles that induce apoptosis in breast cancer cells by negatively regulating PI3K/Akt/mTOR signaling pathway.

X-Box-Binding Protein 1 and Innate Immune Responses of Human Cystic Fibrosis Alveolar Macrophages

RATIONALE

Alveolar macrophages (AMs) play a key role in host defense to inhaled bacterial pathogens, in part by secreting inflammatory mediators. Cystic fibrosis (CF) airways exhibit a persistent, robust inflammatory response that may contribute to the pathophysiology of CF. Recent findings have linked endoplasmic reticulum stress responses mediated by inositol-requiring enzyme 1α-dependent messenger RNA splicing (activation) of X-box-binding protein-1 (XBP-1s) to inflammation in peripheral macrophages. However, the role of XBP-1s in CF AM function is not known.

OBJECTIVES

To evaluate inflammatory responses of AMs from chronically infected/inflamed human CF lungs and test whether XBP-1s is required for AM-mediated inflammation.

METHODS

Basal and LPS-induced inflammatory responses were evaluated in primary cultures of non-CF versus CF AMs. XBP-1s was measured and its function was evaluated in AMs using 8-formyl-7-hydroxy-4-methylcoumarin (4μ8C), an inhibitor of inositol-requiring enzyme 1α-dependent XBP-1s, and in THP-1 cells stably expressing XBP-1 shRNA, XBP-1s, or a dominant-negative XBP-1.

MEASUREMENTS AND MAIN RESULTS

CF AMs exhibited exaggerated basal and LPS-induced production of tumor necrosis factor-α and IL-6, and these responses were coupled to increased levels of XBP-1s. In non-CF and CF AMs, LPS-induced cytokine production was blunted by 4µ8C. A role for XBP-1s in AM inflammatory responses was further established by data from dTHP-1 cells indicating that expression of XBP-1 shRNA reduced XBP-1s levels and LPS-induced inflammatory responses; and LPS-induced inflammation was up-regulated by expression of XBP-1s and inhibited by dominant-negative XBP-1.

CONCLUSIONS

These findings suggest that AMs contribute to the robust inflammation of CF airways via an up-regulation of XBP-1s-mediated cytokine production.

Recent developments of C-4 substituted coumarin derivatives as anticancer agents

Cancer is a prominent cause of death in global. Currently, the numbers of drugs that are in clinical practice are having a high prevalence of side effect and multidrug resistance. Researchers have made an attempt to expand a suitable anticancer drug that has no MDR and side effect. Coumarin scaffold became an attractive subject due to their broad spectrum of pharmacological activities. Coumarin derivatives extensively explored for anticancer activities as it possesses minimum side effect along with multi-drug reversal activity. Coumarin derivatives can act by various mechanisms on different tumor cell lines depending on substitution pattern of the core structure of coumarin. Substitution on coumarin nucleus leads to the search for more potent compounds. In this review, we have made an effort to give a synthetic strategy for the preparation of C-4 substituted coumarin derivatives as anticancer agents based on their mechanism of action and also discuss the SAR of the most active compound.

Nano-MoO3-mediated synthesis of bioactive thiazolidin-4-ones acting as anti-bacterial agents and their mode-of-action analysis using in silico target prediction, docking and similarity searching

Thiazolidin-4-ones inhibit bacterial growth by potentially targeting the FtsK motor domain of DNA translocase ofSalmonella typhi.

Adamantyl-tethered-biphenylic compounds induce apoptosis in cancer cells by targeting Bcl homologs

Bcl homologs prominently contribute to apoptotic resistance in cancer cells and serve as molecular targets in treatment of various cancers. Herein, we report the synthesis of biphenyl-adamantane derivatives by a ligand free palladium on carbon based Suzuki reaction using diisopropylamine as a base for the coupling of adamantane based aryl chloride with a variety of aryl boronic acids. Among the biphenyl derivatives synthesized, compound 3'-(adamantan-1-yl)-4'-methoxy-[1,1'-biphenyl]-3-ol (AMB) displayed cytotoxic activity against hepatocellular carcinoma cell lines without significantly affecting the normal cell lines. Further, AMB caused increased accumulation of the HCC cells in subG1 phase, decreased the expression of Bcl-2, Bcl-xL, cyclin D1, caspase-3, survivin and increased the cleavage of PARP in a time-dependent manner. In silico molecular interaction studies between Bcl homologs and AMB showed that the biphenyl scaffold is predicted to form π-π interactions with Phe-101 and Tyr-105 and the adamantyl fragment is predicted to occupy another hydrophobic region in the kink region of the binding groove. In summary, we report on the synthesis and biological characterization of adamantyl-tethered biphenylic compounds that induce apoptosis in tumor cells most likely by targeting Bcl homologs.

A Nano-MgO and Ionic Liquid-Catalyzed 'Green' Synthesis Protocol for the Development of Adamantyl-Imidazolo-Thiadiazoles as Anti-Tuberculosis Agents Targeting Sterol 14α-Demethylase (CYP51)

In this work, we describe the 'green' synthesis of novel 6-(adamantan-1-yl)-2-substituted-imidazo[2,1-b][1,3,4]thiadiazoles (AITs) by ring formation reactions using 1-(adamantan-1-yl)-2-bromoethanone and 5-alkyl/aryl-2-amino1,3,4-thiadiazoles on a nano material base in ionic liquid media. Given the established activity of imidazothiadiazoles against M. tuberculosis, we next examined the anti-TB activity of AITs against the H37Rv strain using Alamar blue assay. Among the tested compounds 6-(adamantan-1-yl)-2-(4-methoxyphenyl)imidazo[2,1-b][1,3,4]thiadiazole (3f) showed potent inhibitory activity towards M. tuberculosis with an MIC value of 8.5 μM. The inhibitory effect of this molecule against M. tuberculosis was comparable to the standard drugs such as Pyrazinamide, Streptomycin, and Ciprofloxacin drugs. Mechanistically, an in silico analysis predicted sterol 14α-demethylase (CYP51) as the likely target and experimental activity of 3f in this system corroborated the in silico target prediction. In summary, we herein report the synthesis and biological evaluation of novel AITs against M. tuberculosis that likely target CYP51 to induce their antimycobacterial activity.

Esculin and its oligomer fractions inhibit adhesion and migration of U87 glioblastoma cells and in vitro angiogenesis

Cancer metastasis is the major cause of cancer-related death. Chemoprevention is defined as the use of natural or synthetic substances to prevent cancer formation or cancer progress. In the present study, we investigate the antitumor activity of esculin and its oligomer fractions in U87 glioblastoma cells. We showed that esculin and its oligomers reduced U87 cell growth in a dose dependent manner. They also inhibited cell adhesion to collagen IV and vitronectin by interfering with the function of their respective receptors α2β1 and αvβ5 integrins. Furthermore, the tested samples were able to reduce migration of U87 cells towards another extracellular matrix fibronectin. Moreover, esculin and its oligomer fractions inhibited in vitro angiogenesis of endothelial cells (HMEC-1). In summary, our data provide the first evidence that esculin and its oligomer fractions are able to reduce adhesion, migration of glioblastoma cells and in vitro angiogenesis. Esculin and its oligomers may thus exert multi-target functions against cancer cells.