Synthesis of Some Novel Thiophene Analogues as Potential Anticancer Agents.

The aim of this study involves the synthesis novel thiophene analogues that can be used as anticancer medications through a strategic multicomponent reaction connecting ethyl 4-chloroacetoacetate (1), phenyl isothiocyanate, and a series of active methylene reagents, including ethyl acetoacetate (2), malononitrile, ethyl cyanoacetate, cyanoacetamide 6a-c, N-phenyl cyanoacetamide derivatives 13a-c, and acetoacetanilide derivatives 18. This reaction was facilitated by dry dimethylformamide with a catalytic quantity of K2CO3. The resultant thiophene derivatives were identified as 4, 8a-b, 9, 12a-d, 15a-c, and 20a-b. Further reaction of compound 4 with hydrazine hydrate yielded derivative 5, respectively. When compound 1 was refluxed with ethyl 3-mercapto-3-(phenylamino)-2-(p-substituted phenyldiazenyl)acrylate 10a-e in the presence of sodium ethoxide, it produced thiophene derivatives 12a-d. Comprehensive structural elucidation of these newly synthesized thiophene-analogues was accomplished via elemental and spectral analysis data. Furthermore, the study delves into the cytotoxicity of the newly synthesized thiophenes was evaluated using the HepG2, A2780, and A2780CP cell lines. The amino-thiophene derivative 15b exhibited an increased growth inhibition of A2780, and A2780CP with IC50 values 12±0.17, and 10±0.15 µM, respectively compared to Sorafenib with IC50 values 7.5±0.54 and 9.4±0.14. This research opens new avenues for developing thiophene-based anticancer agents.

Adiponectin Gene Polymorphisms and Possible Susceptibility to Metabolic Syndrome among the Sudanese Population: A Case-Control Study.

Results: There is a significant difference in genotypic frequencies of the rs266729, rs2241766, and rs1501299 SNPs and allele frequencies (P < 0.05) between the MetS patients and non-MetS group. MetS patients had a significantly higher serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein-cholesterol (LDL-C) in the GG genotype of rs2241766 (P < 0.05). Additionally; the TT genotype of rs1501299 had higher SBP, serum TG, TC, and LDL-C (P < 0.05). Multivariate logistic regression analysis showed hypertension, hyperglycemia, BMI, WC, serum TG, ADIPOQ rs2241766 (TG allele), and ADIPOQ rs1501299 (GT allele) had independently predicted the incidence of metabolic syndrome in the Sudanese population. The three investigated SNPs of ADIPOQ were in a moderate linkage disequilibrium (LD) connection according to the LD measures (D' = 0.54, 0.62, and 0.69, respectively). The CTT, CGG, and GTG haplotypes, which consist of three alleles of -11377C > G, +45T > G, and +276G > T, were shown to report 1.788-, 1.622,- and 1.641-fold risks toward MetS susceptibility in Sudanese's population, respectively. Conclusion: Along with clinical and biochemical signs, the ADIPOQ gene's genetic variants (rs266729, rs2241766, and rs1501299), CTT, CGG, and GTG haplotypes are connected to the MetS risk among the Sudanese population.

Cell membrane enveloped polymeric nanosponge for detoxification of chlorpyrifos poison: In vitro and in vivo studies.

Organophosphates are highly toxic compounds as they are involved in irreversible inhibition of acetylcholinesterase, causing various neurotoxic effects via acetylcholine accumulation throughout the nervous system. Traditional treatments for organophosphate poisoning are not effective enough to overcome all the toxic effects. There is a need for alternate treatment of life threatening poisoning of organophosphates. For this purpose a biomimetic nanosponge of poly (lactic-co-glycolic acid) is prepared, characterized and analysed as an antidote for organophosphate poisoning. In this nanosponge red blood cell membranes are used for coating poly lactic co-glycolic acid nanoparticles. In vitro studies are conducted to investigate the retention of acetylcholinesterase activity on the prepared nanosponge as well as to assess the scavenging ability of prepared nanosponge for model organophosphate, chlorpyrifos. In vivo studies are conducted to evaluate the detoxification potential of nanosponge in rabbit model, poisoned with chlorpyrifos. Hepatotoxicity and renal toxicity of nanosponge/chlorpyrifos complex is also studied in survived rabbits and the data is analysed statistically.

Comparative Study of Selenides and Tellurides of Transition Metals (Nb and Ta) with Respect to its Catalytic, Antimicrobial, and Molecular Docking Performance.

The present research is a comparative study that reports an economical and accessible method to synthesize niobium (Nb) and Tantalum (Ta) selenides and tellurides with useful application in the removal of pollutants in textile, paper, and dyeing industries as well as in medical field. In this study, solid-state process was used to generate nanocomposites and various characterization techniques were employed to compare two groups of materials under investigation. Structure, morphology, elemental constitution, and functional groups of synthesized materials were analyzed with XRD, FESEM coupled with EDS, FTIR, and Raman spectroscopy, respectively. HR-TEM images displayed nanoscale particles with tetragonal and monoclinic crystal structures. The optical properties were evaluated in terms of cut-off wavelength and optical band gap using UV-visible spectroscopy. A comparative behavior of both groups of compounds was assessed with regards to their catalytic and microcidal properties. Extracted nanocomposites when used as catalysts, though isomorphs of each other, showed markedly different behavior in catalytic degradation of MB dye in the presence of NaBH4 that was employed as a reducing agent. This peculiar deviation might be attributed to slight structural differences between them. Escherichia coli and Staphylococcus aureus (G -ve and + ve bacteria, respectively) were designated as model strains for in vitro antibacterial tests of both clusters by employing disk diffusion method. Superior antibacterial efficacy was observed for telluride system (significant inhibition zones of 26-35 mm) compared with selenide system (diameter of inhibition zone ranged from 0.8 mm to 1.9 mm). In addition, molecular docking study was undertaken to ascertain the binding interaction pattern between NPs and active sites in targeted cell protein. The findings were in agreement with antimicrobial test results suggesting NbTe4 to be the best inhibitor against FabH and FabI enzymes.

MitoNEET (CISD1) Knockout Mice Show Signs of Striatal Mitochondrial Dysfunction and a Parkinson's Disease Phenotype.

Mitochondrial dysfunction is thought to play a significant role in neurodegeneration observed in Parkinson's disease (PD), yet the mechanisms underlying this pathology remain unclear. Here, we demonstrate that loss of mitoNEET (CISD1), an iron-sulfur containing protein that regulates mitochondrial bioenergetics, results in mitochondrial dysfunction and loss of striatal dopamine and tyrosine hydroxylase. Mitochondria isolated from mice lacking mitoNEET were dysfunctional as revealed by elevated reactive oxygen species (ROS) and reduced capacity to produce ATP. Gait analysis revealed a shortened stride length and decreased rotarod performance in knockout mice, consistent with the loss of striatal dopamine. Together, these data suggest that mitoNEET KO mice exhibit many of the characteristics of early neurodegeneration in PD and may provide a novel drug discovery platform to evaluate compounds for enhancing mitochondrial function in neurodegenerative disorders.

Structure-activity and in vivo evaluation of a novel lipoprotein lipase (LPL) activator.

Elevated triglycerides (TG) contribute towards increased risk for cardiovascular disease. Lipoprotein lipase (LPL) is an enzyme that is responsible for the metabolism of core triglycerides of very-low density lipoproteins (VLDL) and chylomicrons in the vasculature. In this study, we explored the structure-activity relationships of our lead compound (C10d) that we have previously identified as an LPL agonist. We found that the cyclopropyl moiety of C10d is not absolutely necessary for LPL activity. Several substitutions were found to result in loss of LPL activity. The compound C10d was also tested in vivo for its lipid lowering activity. Mice were fed a high-fat diet (HFD) for four months, and treated for one week at 10mg/kg. At this dose, C10d exhibited in vivo biological activity as indicated by lower TG and cholesterol levels as well as reduced body fat content as determined by ECHO-MRI. Furthermore, C10d also reduced the HFD induced fat accumulation in the liver. Our study has provided insights into the structural and functional characteristics of this novel LPL activator.

Emerging strategies of targeting lipoprotein lipase for metabolic and cardiovascular diseases.

Although statins and other pharmacological approaches have improved the management of lipid abnormalities, there exists a need for newer treatment modalities especially for the management of hypertriglyceridemia. Lipoprotein lipase (LPL), by promoting hydrolytic cleavage of the triglyceride core of lipoproteins, is a crucial node in the management of plasma lipid levels. Although LPL expression and activity modulation is observed as a pleiotropic action of some the commonly used lipid lowering drugs, the deliberate development of drugs targeting LPL has not occurred yet. In this review, we present the biology of LPL, highlight the LPL modulation property of currently used drugs and review the novel emerging approaches to target LPL.

Identification of small molecules that bind to the mitochondrial protein mitoNEET.

MitoNEET (CISD1) is a 2Fe-2S iron-sulfur cluster protein belonging to the zinc-finger protein family. Recently mitoNEET has been shown to be a major role player in the mitochondrial function associated with metabolic type diseases such as obesity and cancers. The anti-diabetic drug pioglitazone and rosiglitazone were the first identified ligands to mitoNEET. Since little is known about structural requirements for ligand binding to mitoNEET, we screened a small set of compounds to gain insight into these requirements. We found that the thiazolidinedione (TZD) warhead as seen in rosiglitazone was not an absolutely necessity for binding to mitoNEET. These results will aid in the development of novel compounds that can be used to treat mitochondrial dysfunction seen in several diseases.

Twenty-eight loci that influence serum urate levels: analysis of association with gout.

OBJECTIVES: Twenty-eight genetic loci are associated with serum urate levels in Europeans. Evidence for association with gout at most loci is absent, equivocal or not replicated. Our aim was to test the loci for association with gout meeting the American College of Rheumatology gout classification criteria in New Zealand European and Polynesian case-control sample sets. METHODS: 648 European cases and 1550 controls, and 888 Polynesian (Ma¯ori and Pacific) cases and 1095 controls were genotyped. Association with gout was tested by logistic regression adjusting for age and sex. Power was adequate (>0.7) to detect effects of OR>1.3. RESULTS: We focused on 24 loci without previous consistent evidence for association with gout. In Europeans, we detected association at seven loci, one of which was the first report of association with gout (IGF1R). In Polynesian, association was detected at three loci. Meta-analysis revealed association at eight loci-two had not previously been associated with gout (PDZK1 and MAF). In participants with higher Polynesian ancestry, there was association in an opposing direction to Europeans at PRKAG2 and HLF (HLF is the first report of association with gout). There was obvious inconsistency of gout association at four loci (GCKR, INHBC, SLC22A11, SLC16A9) that display very similar effects on urate levels. CONCLUSIONS: We provide the first evidence for association with gout at four loci (IGF1R, PDZK1, MAF, HLF). Understanding why there is lack of correlation between urate and gout effect sizes will be important in understanding the aetiology of gout.

Inducible Nitric Oxide Inhibitors Block NMDA Antagonist-Stimulated Motoric Behaviors and Medial Prefrontal Cortical Glutamate Efflux.

Nitric oxide (NO) plays a critical role in the motoric and glutamate releasing action of N-methyl-D-aspartate (NMDA)-antagonist stimulants. Earlier studies utilized neuronal nitric oxide synthase inhibitors (nNOS) for studying the neurobehavioral effects of non-competitive NMDA-antagonist stimulants such as dizocilpine (MK-801) and phencyclidine (PCP). This study explores the role of the inducible nitric oxide synthase inhibitors (iNOS) aminoguanidine (AG) and (-)-epigallocatechin-3-gallate (EGCG) in NMDA-antagonist induced motoric behavior and prefrontal cortical glutamate efflux. Adult male rats were administered a dose range of AG, EGCG, or vehicle prior to receiving NMDA antagonists MK-801, PCP, or a conventional psychostimulant (cocaine) and tested for motoric behavior in an open arena. Glutamate in the medial prefrontal cortex (mPFC) was measured using in vivo microdialysis after a combination of AG or EGCG prior to MK-801. Acute administration of AG or EGCG dose-dependently attenuated the locomotor and ataxic properties of MK-801 and PCP. Both AG and EGCG were unable to block the motoric effects of cocaine, indicating the acute pharmacologic action of AG and EGCG is specific to NMDA antagonism and not generalizable to all stimulant class drugs. AG and EGCG normalized MK-801-stimulated mPFC glutamate efflux. These data demonstrate that AG and EGCG attenuates NMDA antagonist-stimulated motoric behavior and cortical glutamate efflux. Our results suggest that EGCG-like polyphenol nutraceuticals (contained in "green tea" and chocolate) may be clinically useful in protecting against the adverse behavioral dissociative and cortical glutamate stimulating effects of NMDA antagonists. Medications that interfere with NMDA antagonists such as MK-801 and PCP have been proposed as treatments for schizophrenia.

Evolution of a Natural Products and Nutraceuticals Course in the Pharmacy Curriculum.

Objective. To develop, implement, and modify a required, second-year pharmacy course that provides an understanding of the scientific, therapeutic, and clinical principles, as well as the evidence-based medicine underlying the use of natural products. Design. A 28-hour, multi-faculty course was developed and offered in 2008. The course was modified over the years to enhance students' practice skills in the use of natural products. A course evaluation and survey were administered to assess the students' opinions. Assessment. Students performed well in the course and provided favorable evaluations, especially for the latest offering. Students reported significantly improved skills in providing advice to patients regarding the use of natural products. Conclusion. The course increased the students' knowledge and application of information and counseling skills regarding natural products.

Pharmacotherapy of Alzheimer's disease: current and future trends.

Alzheimer's disease (AD) and its related dementia has shown an alarming rise in the global population. Although considerable efforts have been made to develop effective therapeutic agents for AD therapy, drug development has not met significant clinical success. Current pharmacotherapy of AD is limited to cholinesterase inhibitors and the N-methyl-D-aspartate antagonist memantine. Considerable research is underway to develop newer agents for the management of AD. Since amyloid-ß (Aß) has been implicated in AD pathogenesis, the use of ß secretase inhibitors as well as immunotherapy against Aß has been investigated. A considerable effort has been spent investigating the therapeutic potential of antioxidants and anti-inflammatory agents, several of natural products and dietary origin, in AD treatment. Numerous drug targets have also been investigated for AD treatment and a modest drug pipeline is available. Despite these efforts, drug development for AD has proved extremely difficult and most clinical trials have afforded disappointing results.

Pomegranate Bioactive Constituents Suppress Cell Proliferation and Induce Apoptosis in an Experimental Model of Hepatocellular Carcinoma: Role of Wnt/ ß -Catenin Signaling Pathway.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide, and chemoprevention represents a viable approach in lowering the mortality of this disease. Pomegranate fruit, an abundant source of anti-inflammatory phytochemicals, is gaining tremendous attention for its wide-spectrum health benefits. We previously reported that a characterized pomegranate emulsion (PE) prevents diethylnitrosamine (DENA)-induced rat hepatocarcinogenesis though inhibition of nuclear factor-kappaB (NF- κ B). Since NF- κ B concurrently induces Wnt/ ß -catenin signaling implicated in cell proliferation, cell survival, and apoptosis evasion, we examined antiproliferative, apoptosis-inducing and Wnt/ ß -catenin signaling-modulatory mechanisms of PE during DENA rat hepatocarcinogenesis. PE (1 or 10 g/kg) was administered 4 weeks before and 18 weeks following DENA exposure. There was a significant increase in hepatic proliferation (proliferating cell nuclear antigen) and alteration in cell cycle progression (cyclin D1) due to DENA treatment, and PE dose dependently reversed these effects. PE substantially induced apoptosis by upregulating proapoptotic protein Bax and downregulating antiapoptotic protein Bcl-2. PE dose dependently reduced hepatic ß -catenin and augmented glycogen synthase kinase-3 ß expression. Our study provides evidence that pomegranate phytochemicals exert chemoprevention of hepatic cancer through antiproliferative and proapoptotic mechanisms by modulating Wnt/ ß -catenin signaling. PE, thus, targets two interconnected molecular circuits (canonical NF- κ B and Wnt/ ß -catenin pathways) to exert chemoprevention of HCC.

Chemopreventive and therapeutic potential of tea polyphenols in hepatocellular cancer.

The prophylactic and therapeutic properties of tea have been attributed to green tea catechins and black tea theaflavins besides several other polyphenolic compounds. Tea polyphenols possess potent antioxidant and antiinflammatory properties and modulate several signaling pathways. These biochemical facets of tea polyphenols are responsible for its anticancer properties. Several lethal cancers, such as liver cancer, develop within a background of oxidative stress and inflammation. Liver cancer, also known as hepatocellular carcinoma (HCC), has been shown to occur throughout the world including Asia, Africa, Western Europe, and the United States. Phytochemicals, such as tea polyphenols, provide an effective and promising alternative for the chemoprevention and treatment of HCC. In this article, we systematically review, for the first time, the effects of tea polyphenols in the preclinical in vitro and in vivo HCC models. The review also examines, in critical detail, the biochemical mechanisms involved in the chemopreventive and antineoplastic effects of tea polyphenols in hepatic cancer. Finally, we highlight the role of synergy, bioavailability and pharmacokinetics of tea polyphenols, current status of clinical trials, discuss future directions, and comment on the future challenges involved in the effective use of tea polyphenols for the prevention and management of liver cancer.

Chemopreventive effect of a novel oleanane triterpenoid in a chemically induced rodent model of breast cancer.

Breast cancer represents one of the most frequently diagnosed cancers and predominant causes of death in women worldwide. The value of preventive therapy to limit the devastating impact of breast cancer is well established. Various plant triterpenoids and their synthetic analogs have shown significant promise as potent chemopreventive agents in breast cancer. The current study was initiated to investigate mechanism-based chemopreventive potential of a novel synthetic oleanane triterpenoid (methyl-25-hydroxy-3-oxoolean-12-en-28-oate, AMR-Me) against 7,12-dimethylbenz(a)anthracene (DMBA)-initiated rat mammary carcinogenesis, an experimental rodent tumor model that closely resembles human mammary cancer. Rats were orally administered with AMR-Me (0.8, 1.2 and 1.6 mg/kg) three times per week for 18 weeks. Following two weeks of AMR-Me treatment, mammary carcinogenesis was initiated by oral administration of DMBA (50 mg/kg body weight). At the end of the study (16 weeks following DMBA exposure), AMR-Me exhibited a striking inhibition of DMBA-induced mammary tumor incidence, total tumor burden, average tumor weight and reversed histopathological alterations without toxicity. AMR-Me dose-dependently suppressed abnormal cell proliferation, induced apoptosis, up-regulated pro-apoptotic protein Bax and down-regulated antiapoptotic protein Bcl-2 in mammary tumors. AMR-Me upregulated the transcriptional levels of Bax, Bad, caspase-3, caspase-7 and poly(ADP-ribose) polymerase and down-regulated Bcl-2. These results clearly demonstrate for the first time that novel triterpenoid AMR-Me exerts chemopreventive efficacy in the classical DMBA model of breast cancer by suppressing abnormal cell proliferation and inducing apoptosis mediated through mitochondrial pro-apoptotic mechanisms. AMR-Me could be developed as a chemopreventive drug to reduce the risk of human breast cancer that remains a devastating disease.

Black currant phytoconstituents exert chemoprevention of diethylnitrosamine-initiated hepatocarcinogenesis by suppression of the inflammatory response.

Black currant fruits containing high amounts of anthocyanins are known to possess potent antioxidant and anti-inflammatory properties. We have previously reported that anthocyanin-rich black currant skin extract (BCSE) inhibits diethylnitrosamine (DENA)-initiated hepatocarcinogenesis in rats although the underlying mechanisms are not fully understood. Our present study investigates the anti-inflammatory mechanisms of BCSE during DENA rat liver carcinogenesis. Dietary BCSE (100 or 500 mg/kg) treatment for 22 wk afforded a striking inhibition of DENA-induced hepatic gamma-glutamyl transpeptidase-positive preneoplastic foci in a dose-responsive fashion. There was a significant increase in hepatic expression of heat shock proteins (HSP70 and HSP90), cyclooxygenase-2, and nuclear factor-κB (NF-κB) in DENA-exposed rat livers. Dietary BCSE dose-dependently abrogated all these elevated inflammatory markers. The possible cardiotoxicity of BCSE was assessed by monitoring cardiac functions using transthoracic echocardiography. BCSE-mediated anti-inflammatory effects during rat liver carcinogenesis have been achieved without any cardiotoxicity. Our results provide convincing evidence, for the very first time, that suppression of the inflammatory cascade through modulation of the NF-κB signaling pathway could be implicated, at least in part, in the chemopreventive effects of black currant bioactive phytoconstituents against experimental hepatocarcinogenesis. These results coupled with an excellent safety profile of BCSE support the development of black currant phytochemicals for the chemoprevention of inflammation-driven hepatocellular cancer.

Pomegranate phytoconstituents blunt the inflammatory cascade in a chemically induced rodent model of hepatocellular carcinogenesis.

Liver cancer, predominantly hepatocellular carcinoma (HCC), represents a complex and fatal malignancy driven primarily by oxidative stress and inflammation. Due to dismal prognosis and limited therapeutic intervention, chemoprevention has emerged as a viable approach to reduce the morbidity and mortality of HCC. Pomegranate fruit is a rich source of phytochemicals endowed with potent antioxidant and anti-inflammatory properties. We previously reported that pomegranate phytochemicals inhibit diethylnitrosamine (DENA)-initiated hepatocarcinogenesis in rats though nuclear factor E2-related factor 2 (Nrf2)-mediated antioxidant mechanisms. Since Nrf2 also acts as a key mediator of the nuclear factor-kappaB (NF-κB)-regulated inflammatory pathway, our present study investigated the anti-inflammatory mechanisms of a pomegranate emulsion (PE) during DENA-induced rat hepatocarcinogenesis. Rats were administered with PE (1 or 10 g/kg) 4 weeks before and 18 weeks following DENA initiation. There was a significant increase in hepatic expressions of inducible nitric oxide synthase, 3-nitrotyrosine, heat shock protein 70 and 90, cyclooxygenase-2 and NF-κB in DENA-exposed rat livers. PE dose-dependently suppressed all aforementioned elevated inflammatory markers. A conspicuous finding of this study involves lack of cardiotoxicity of PE as assessed by monitoring cardiac function using noninvasive echocardiography. Our results provide substantial evidence that suppression of the inflammatory cascade through modulation of NF-κB signaling pathway may represent a novel mechanism of liver tumor inhibitory effects of PE against experimental hepatocarcinogenesis. Data presented here coupled with those of our earlier study underline the importance of simultaneously targeting two interconnected molecular circuits, namely, Nrf2-mediated redox signaling and NF-κB-regulated inflammatory pathway, by pomegranate phytoconstituents to achieve chemoprevention of HCC.

Black currant anthocyanins abrogate oxidative stress through Nrf2- mediated antioxidant mechanisms in a rat model of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC), considered to be one of the most lethal cancers with almost > 1 million deaths reported annually worldwide, remains a devastating disease with no known effective cure. Hence, chemopreventive strategies come into play, offering an effective and safe mode of treatment, ideal to ward off potential cancer risks and mortality. A major predisposing condition, pertinent to the development and progression of HCC is oxidative stress. We previously reported a striking chemopreventive effect of anthocyanin-rich black currant skin extract (BCSE) against diethylnitrosamine (DENA)-initiated hepatocarcinogenesis in rats. The current study aims to elucidate the underlying antioxidant mechanisms of black currant anthocyanins implicated in the previously observed chemopreventive effects against experimental hepatocarcinogenesis. Dietary BCSE (100 and 500 mg/kg) administered four weeks before and 18 weeks after DENA challenge decreased abnormal lipid peroxidation, protein oxidation, and expression of inducible nitric oxide synthase (iNOS) and 3-nitrotyrosine (3-NT) in a dose-responsive fashion. Mechanistic studies revealed that BCSE upregulated the gene expression of a number of hepatic antioxidant and carcinogen detoxifying enzymes, such as NAD(P)H:quinone oxidoreductase, glutathione S-transferase, and uridine diphosphate-glucuronosyltransferase isoenzymes, in DENA-initiated animals. Protein and mRNA expressions of nuclear factor E2-related factor 2 (Nrf2) were substantially elevated with BCSE treatment, providing a direct evidence of a coordinated activation of the Nrf2-regulated antioxidant pathway, which led to the upregulation of a variety of housekeeping genes. The results of our study provide substantial evidence that black currant bioactive anthocyanins exert chemopreventive actions against DENA-inflicted hepatocarcinogenesis by attenuating oxidative stress through activation of Nrf2 signaling pathway.

Angiogenesis in hepatocellular carcinoma: a potential target for chemoprevention and therapy.

Hepatocellular carcinoma (HCC) remains one of the most lethal cancers in the world. Since current treatment options including surgical resection and liver transplantation offer limited therapeutic benefits, there exists a need to evaluate novel therapeutic strategies for the amelioration of HCC. Hepatic tumors are highly vascularized, possessing a rich network of blood vessels and capillaries and there exist an angiogenic component to the tumor growth observed in HCC. Thus, anti-angiogenic therapy has been suggested to possess tremendous therapeutic potential in the treatment of HCC. The process of angiogenesis involves multiple biochemical checkpoints and signaling steps, and thus providing a multitude of opportunities for therapeutic intervention. In this review, we highlight the role of angiogenesis and its use as a therapeutic strategy for HCC. The first part of the article reviews the angiogenic mechanisms with particular emphasis on the multitude of biochemical factors, such as receptors, enzymes and cytokines involved in the complex interplay of new capillary growth. Next, we present the pre-clinical studies which elucidate the anti-angiogenic effects of both dietary and non-dietary agents in animal models of HCC. Of particular interest is the examination of the effects of the antiangiogenic agents on the various angiogenic markers in the hepatic tissue of the animal challenged either with a hepatocarcinogen or xenografted with hepatic neoplastic cells. The review also highlights the clinical investigations carried out in HCC patients to evaluate the therapeutic potential of pharmacological agents with proven anti-angiogenic properties. Finally, the future directions as well as the benefits and potential challenges involved in the use of antiangiogenic pharmacotherapy in the treatment of HCC are also discussed.

Dietary phytochemicals in the chemoprevention and treatment of hepatocellular carcinoma: in vivo evidence, molecular targets, and clinical relevance.

Hepatocellular carcinoma (HCC), one of the most common and lethal cancers, is a growing menace in modern society. Until recently, the majority of detected cases of liver cancer have been found in the developing nations of Asia and Africa; however, its occurrence has significantly increased in the United States. HCC occurs due to several etiologies, such as alcoholism, dietary carcinogens, iron overload, viral hepatitis, as well as several hepatic chronic diseases. In view of the limited treatment options, such as surgery and transplantation, a critical need exists to examine alternative approaches. The use of phytochemicals obtained from dietary sources provides a novel and fascinating preventive and therapeutic approach against HCC. Dietary phytochemicals possess potent antioxidant and anti-inflammatory properties which are extremely critical to combat the significant oxidative stress and inflammation implicated in liver cancer. An impressive number of phytochemicals have shown considerable promise as candidates for the prevention and treatment of HCC. In this article, we systematically review the in vivo pre-clinical evidence documenting the chemopreventive and therapeutic potential of several important dietary phytochemicals in HCC. This review critically examines the molecular mechanisms of the pharmacological effects of the aforementioned animal studies. Clinical and epidemiological studies are also highlighted in this review. Emerging issues such as bioavailability, dose optimization, targeted drug delivery, role of botanical extracts and synergy are also discussed. Finally, current challenges, limitations, future directions, innovative concepts and novel hypotheses for the use of dietary phytochemicals in the chemoprevention and amelioration of human HCC are presented.