Publications by authors named "Thomas E Adrian"

66 Publications

Thymoquinone, a Dietary Bioactive Compound, Exerts Anti-Inflammatory Effects in Colitis by Stimulating Expression of the Colonic Epithelial PPAR-γ Transcription Factor.

Nutrients 2021 Apr 17;13(4). Epub 2021 Apr 17.

Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain PO Box 17666, United Arab Emirates.

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders with increasing incidence and prevalence worldwide. Here, we investigated thymoquinone (TQ), a naturally occurring phytochemical present in , for anti-inflammatory effects in colonic inflammation. To address this, we used in vivo (mice) and in vitro (HT-29 cells) models in this investigation. Our results showed that TQ treatment significantly reduced the disease activity index (DAI), myeloperoxidase (MPO) activity, and protected colon microscopic architecture. In addition, TQ also reduced the expression of proinflammatory cytokines and mediators at both the mRNA and protein levels. Further, TQ decreased phosphorylation of the activated mitogen-activated protein kinase (MAPK) signaling pathway and nuclear factor kappa B (NF-κB) proteins and enhanced colon epithelial PPAR-γ transcription factor expression. TQ significantly decreased proinflammatory chemokines (CXCL-1 and IL-8), and mediator (COX-2) mRNA expression in HT-29 cells treated with TNF-α. TQ also increased HT-29 PPAR-γ mRNA, PPAR-γ protein expression, and PPAR-γ promoter activity. These results indicate that TQ inhibits MAPK and NF-κB signaling pathways and transcriptionally regulates PPAR-γ expression to induce potent anti-inflammatory activity in vivo and in vitro models of colon inflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/nu13041343DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8073634PMC
April 2021

Nerolidol Mitigates Colonic Inflammation: An Experimental Study Using both In Vivo and In Vitro Models.

Nutrients 2020 Jul 8;12(7). Epub 2020 Jul 8.

Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain 17666, UAE.

Nerolidol (NED) is a naturally occurring sesquiterpene alcohol present in various plants with potent anti-inflammatory effects. In the current study, we investigated NED as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J) were administered 3% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colitis. Six groups received either vehicle alone or DSS alone or DSS with oral NED (50, 100, and 150 mg/kg body weight/day by oral gavage) or DSS with sulfasalazine. Disease activity index (DAI), colonic histology, and biochemical parameters were measured. TNF-α-treated HT-29 cells were used as in vitro model of colonic inflammation to study NED (25 µM and 50 µM). NED significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue Myeloperoxidase (MPO) concentrations, neutrophil and macrophage mRNA expression (CXCL2 and CCL2), and proinflammatory cytokine content (IL-1β, IL-6, and TNF-α) both at the protein and mRNA level were significantly reduced by NED. The increase in content of the proinflammatory enzymes, COX-2 and iNOS induced by DSS were also significantly inhibited by NED along with tissue nitrate levels. NED promoted Nrf2 nuclear translocation dose dependently. NED significantly increased antioxidant enzymes activity (Superoxide dismutase (SOD) and Catalase (CAT)), Hemeoxygenase-1 (HO-1), and SOD3 mRNA levels. NED treatment in TNF-α-challenged HT-29 cells significantly decreased proinflammatory chemokines (CXCL1, IL-8, CCL2) and COX-2 mRNA levels. NED supplementation attenuates colon inflammation through its potent antioxidant and anti-inflammatory activity both in in vivo and in vitro models of colonic inflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/nu12072032DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7400891PMC
July 2020

SARS-CoV-2/COVID-19: Viral Genomics, Epidemiology, Vaccines, and Therapeutic Interventions.

Viruses 2020 05 10;12(5). Epub 2020 May 10.

College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, UAE.

The COVID-19 pandemic is due to infection caused by the novel SARS-CoV-2 virus that impacts the lower respiratory tract. The spectrum of symptoms ranges from asymptomatic infections to mild respiratory symptoms to the lethal form of COVID-19 which is associated with severe pneumonia, acute respiratory distress, and fatality. To address this global crisis, up-to-date information on viral genomics and transcriptomics is crucial for understanding the origins and global dispersion of the virus, providing insights into viral pathogenicity, transmission, and epidemiology, and enabling strategies for therapeutic interventions, drug discovery, and vaccine development. Therefore, this review provides a comprehensive overview of COVID-19 epidemiology, genomic etiology, findings from recent transcriptomic map analysis, viral-human protein interactions, molecular diagnostics, and the current status of vaccine and novel therapeutic intervention development. Moreover, we provide an extensive list of resources that will help the scientific community access numerous types of databases related to SARS-CoV-2 OMICs and approaches to therapeutics related to COVID-19 treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/v12050526DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7290442PMC
May 2020

Ileal Transposition in Rats Reduces Energy Intake, Body Weight, and Body Fat Most Efficaciously When Ingesting a High-Protein Diet.

Obes Surg 2020 07;30(7):2729-2742

Department of Behavioral Neuroscience, Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, Groningen, the Netherlands.

Purpose: Ileal transposition (IT) allows exploration of hindgut effects of bariatric procedures in inducing weight loss and reducing adiposity. Here we investigated the role of dietary macronutrient content on IT effects in rats.

Methods: Male Lewis rats consuming one of three isocaloric liquid diets enriched with fat (HF), carbohydrates (HC), or protein (HP) underwent IT or sham surgery. Body weight, energy intake, energy efficiency, body composition, and (meal-induced) changes in plasma GIP, GLP-1, PYY, neurotensin, and insulin levels were measured.

Results: Following IT, HC intake remained highest leading to smallest weight loss among dietary groups. IT in HF rats caused high initial weight loss and profound hypophagia, but the rats caught up later, and finally had the highest body fat content among IT rats. HP diet most efficaciously supported IT-induced reduction in body weight and adiposity, but (as opposed to other diet groups) lean mass was also reduced. Energy efficiency decreased immediately after IT irrespective of diet, but normalized later. Energy intake alone explained variation in post-operative weight change by 80%. GLP-1, neurotensin, and PYY were upregulated by IT, particularly during (0-60 min) and following 17-h post-ingestive intake, with marginal diet effects. Thirty-day post-operative cumulative energy intake was negatively correlated to 17-h post-ingestive PYY levels, explaining 47% of its variation.

Conclusion: Reduction in energy intake underlies IT-induced weight loss, with highest efficacy of the HP diet. PYY, GLP-1, and neurotensin levels are upregulated by IT, of which PYY may be most specifically related to reduced intake and weight loss after IT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11695-020-04565-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7260147PMC
July 2020

Phytochemical drug candidates for the modulation of peroxisome proliferator-activated receptor γ in inflammatory bowel diseases.

Phytother Res 2020 Jul 3;34(7):1530-1549. Epub 2020 Feb 3.

Department of Physiology, Zayed Bin Sultan Center for Health Sciences, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.

Plant-based compounds or phytochemicals such as alkaloids, glycosides, flavonoids, volatile oils, tannins, resins, and polyphenols have been used extensively in traditional medicine for centuries and more recently in Western alternative medicine. Extensive evidence suggests that consumption of dietary polyphenolic compounds lowers the risk of inflammatory diseases. The anti-inflammatory properties of several phytochemicals are mediated through ligand-inducible peroxisome proliferator-activated receptors (PPARs), particularly the PPARγ transcription factor. Inflammatory bowel disease (IBD) is represented by ulcerative colitis, which occurs in the mucosa of the colon and rectum, and Crohn's disease (CD) that can involve any segment of gastrointestinal tract. Because of the lack of cost-effective pharmaceutical treatment options, many IBD patients seek and use alternative and unconventional therapies to alleviate their symptoms. PPARγ plays a role in the inhibition of inflammatory cytokine expression and activation of anti-inflammatory immune cells. The phytochemicals reported here are ligands that activate PPARγ, which in turn modulates inflammatory responses. PPARγ is highly expressed in the gut making it a potential therapeutic target for IBDs. This review summarizes the effects of the currently published phytochemicals that modulate the PPARγ pathway and reduce or eliminate colonic inflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ptr.6625DOI Listing
July 2020

1,2,3-Triazolyl ester of ketorolac (15K), a potent PAK1 blocker, inhibits both growth and metastasis of orthotopic human pancreatic cancer xenografts in mice.

Drug Discov Ther 2019 Nov 27;13(5):248-255. Epub 2019 Oct 27.

Department of Physiology, United Arab Emirates University, Al Ain, UAE.

More than 90% of human pancreatic cancers carry the oncogenic mutant of Ki-RAS and their growth depends on its downstream kinase PAK1, mainly because PAK1 blocks the apoptosis of cancer cells selectively. We developed a highly cell-permeable PAK1-blocker called 15K from an old pain-killer (ketorolac), that is shown here to inhibit the growth of three pancreatic cancer cell lines with IC50 values ranging 41-88 nM in vitro. The anti-cancer effect of 15K was further investigated in an orthotopic xenograft model with gemcitabine (GEM)-resistant human pancreatic cancer cell lines (AsPC-1 and BxPC-3) expressing luciferase in athymic mice. During 4 weeks, 15K blocks total burden (growth) of both AsPC-1 and BxPC-3 tumors (measured as radians/sec) with the IC50 below daily dose of 0.1 mg/kg, i.p. In a similar manner 15K reduced both their invasion and metastases as well, while it had no effect on either body weight or hematological parameters even at 5 mg/kg/day. To the best of our knowledge, 15K is so far the most potent among synthetic PAK1-blockers in vivo, and could be potentially useful for therapy of GEM-resistant cancers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5582/ddt.2019.01068DOI Listing
November 2019

Frondanol, a Nutraceutical Extract from , Attenuates Colonic Inflammation in a DSS-Induced Colitis Model in Mice.

Mar Drugs 2018 Apr 30;16(5). Epub 2018 Apr 30.

Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box⁻17666, Al Ain, UAE.

Frondanol is a nutraceutical lipid extract of the intestine of the edible Atlantic sea cucumber, with potent anti-inflammatory effects. In the current study, we investigated Frondanol as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J) were given 3% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colitis. The colitis group received oral Frondanol (100 mg/kg body weight/per day by gavage) and were compared with a control group and the DSS group. Disease activity index (DAI) and colon histology were scored for macroscopic and microscopic changes. Colonic tissue length, myeloperoxidase (MPO) concentration, neutrophil and macrophage marker mRNA, pro-inflammatory cytokine proteins, and their respective mRNAs were measured using ELISA and real-time RT-PCR. The tissue content of leukotriene B4 (LTB4) was also measured using ELISA. Frondanol significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue MPO concentrations, neutrophil and macrophage mRNA expression (F4/80 and MIP-2), and pro-inflammatory cytokine content (IL-1β, IL-6 and TNF-α) both at the protein and mRNA level were significantly reduced by Frondanol. The increase in content of the pro-inflammatory mediator leukotriene B4 (LTB4) induced by DSS was also significantly inhibited by Frondanol. It was thus found that Frondanol supplementation attenuates colon inflammation through its potent anti-inflammatory activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/md16050148DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5983279PMC
April 2018

The Anti-Cancer Effects of Frondoside A.

Mar Drugs 2018 Feb 19;16(2). Epub 2018 Feb 19.

Coastside Bio Resources, Deer Isle, ME 04627, USA.

Frondoside A is a triterpenoid glycoside from the Atlantic Sea Cucumber, . Frondoside A has a broad spectrum of anti-cancer effects, including induction of cellular apoptosis, inhibition of cancer cell growth, migration, invasion, formation of metastases, and angiogenesis. In cell lines and animal models studied to date, the anti-cancer effects of the compound are seen in all solid cancers, lymphomas, and leukemias studied to date. These effects appear to be due to potent inhibition of p21-activated kinase 1 (PAK1), which is up-regulated in many cancers. In mouse models, frondoside A has synergistic effects with conventional chemotherapeutic agents, such as gemcitabine, paclitaxel, and cisplatin. Frondoside A administration is well-tolerated. No side effects have been reported and the compound has no significant effects on body weight, blood cells, or on hepatic and renal function tests after long-term administration. Frondoside A may be valuable in the treatment of malignancies, either as a single agent or in combination with other therapeutic modalities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/md16020064DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5852492PMC
February 2018

Diabetic Neuropathy: Update on Pathophysiological Mechanism and the Possible Involvement of Glutamate Pathways.

Curr Diabetes Rev 2017 ;13(5):488-497

Department of Physiology, College of Medicine and Health Sciences, UAE University, Al Ain. United Arab Emirates.

Introduction: Diabetic neuropathy is a common complication of diabetes. It adversely affects the lives of most diabetics. It is the leading cause of non-traumatic limb amputation. Diabetic autonomic neuropathy can target any system and increases morbidity and mortality. Treatment begins with adequate glycemic control but despite this, many patients go on to develop neuropathy which suggests there are additional and unidentified, as yet, pathological mechanisms in place. Although several theories exist, the exact mechanisms are not yet established. Disease modifying treatment requires a more complete understanding of the mechanisms of disease. Pathways Involved: This review discusses the potential pathological mechanisms of diabetic neuropathy, including the polyol pathway, hexosamine pathway, protein kinase C, advanced glycation end product formation, polyADP ribose polymerase, and the role of oxidative stress, inflammation, growth factors and lipid abnormalities. Finally it focuses on how possible changes in glutamate signaling pathways fit into the current theories.

Conclusion: Insights into the mechanisms involving gene expression in diabetic neuropathy can help pinpoint genes with altered expression. This will help in the development of novel alternative therapeutic strategies to significantly slow the progression of neuropathy in susceptible individuals and perhaps even prevention.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2174/1573399812666160624122605DOI Listing
September 2018

Pharmacokinetics in Mouse and Comparative Effects of Frondosides in Pancreatic Cancer.

Mar Drugs 2016 Jun 17;14(6). Epub 2016 Jun 17.

Department of Physiology, Faculty of Medicine, United Arab Emirates University, P.O. Box 17666, Al Ain, UAE.

The frondosides are triterpenoid glycosides from the Atlantic sea cucumber Cucumaria frondosa. Frondoside A inhibits growth, invasion, metastases and angiogenesis and induces apoptosis in diverse cancer types, including pancreatic cancer. We compared the growth inhibitory effects of three frondosides and their aglycone and related this to the pharmocokinetics and route of administration. Frondoside A potently inhibited growth of pancreatic cancer cells with an EC50 of ~1 µM. Frondoside B was less potent (EC50 ~2.5 µM). Frondoside C and the aglycone had no effect. At 100 µg/kg, frondoside A administered to CD₂F₁ mice as an i.v. bolus, the Cpmax was 129 nM, Cltb was 6.35 mL/min/m², and half-life was 510 min. With i.p. administration the Cpmax was 18.3 nM, Cltb was 127 mL/min/m² and half-life was 840 min. Oral dosing was ineffective. Frondoside A (100 µg/kg/day i.p.) markedly inhibited growth cancer xenografts in nude mice. The same dose delivered by oral gavage had no effect. No evidence of acute toxicity was seen with frondoside A. Frondoside A is more potent inhibitor of cancer growth than other frondosides. The glycoside component is essential for bioactivity. Frondoside A is only effective when administered systemically. Based on the current and previous studies, frondoside A appears safe and may be valuable in the treatment of cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/md14060115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4926074PMC
June 2016

Saffron-Based Crocin Prevents Early Lesions of Liver Cancer: In vivo, In vitro and Network Analyses.

Recent Pat Anticancer Drug Discov 2016 ;11(1):121-33

Biology Department, College of Science, UAE University, Al-Ain P.O. Box 15551, UAE.

Background: The angiogenesis inhibitor, sorafenib, remains the only available therapy of hepatocellular carcinoma (HCC). Only recently patents of VEGF receptors-3 inhibitors are developed. Thus, a novel approach against HCC is essential for a better therapeutic outcome.

Objective: The aims of this study were to examine the chemopreventive action of saffron's main biomolecule, crocin, against chemically-induced liver cancer in rats, and to explore the mechanisms by which crocin employs its anti-tumor effects.

Method: We investigated the anti-cancer effect of crocin on an experimental carcinogenesis model of liver cancer by studying the anti-oxidant, anti-inflammatory, anti-proliferation, pro-apoptotic activities of crocin in vivo. In addition, we provided a network analysis of differentially expressed genes in tissues of animals pre-treated with crocin in comparison to induced-HCC animals' tissues. To further support our results, in vitro analysis was carried out. We assessed the effects of crocin on HepG2 cells viability by treating them with various concentrations of crocin; in addition, effects of crocin on cell cycle distribution of HepG2 cells were investigated.

Results: Findings reported herein demonstrated the anti-proliferative and pro-apoptotic properties of crocin when administrated in induced- HCC model. Crocin exhibited anti-inflammatory properties where NF-κB, among other inflammatory markers, was inhibited. In vitro analysis confirmed crocin's effect in HepG2 by arresting the cell cycle at S and G2/M phases, inducing apoptosis and down regulating inflammation. Network analysis identified NF-κB as a potential regulatory hub, and therefore, a candidate therapeutic drug target.

Conclusion: Taken together, our findings introduce crocin as a candidate chemopreventive agent against HCC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2174/1574892810666151102110248DOI Listing
December 2016

The Effects of Different Repetitive Transcranial Magnetic Stimulation (rTMS) Protocols on Cortical Gene Expression in a Rat Model of Cerebral Ischemic-Reperfusion Injury.

PLoS One 2015 2;10(10):e0139892. Epub 2015 Oct 2.

Department of Physiology, College of Medicine and Health Sciences, UAE University, Al Ain, UAE.

Although repetitive Transcranial Magnetic Stimulation (rTMS) in treatment of stroke in humans has been explored over the past decade the data remain controversial in terms of optimal stimulation parameters and the mechanisms of rTMS long-term effects. This study aimed to explore the potential of different rTMS protocols to induce changes in gene expression in rat cortices after acute ischemic-reperfusion brain injury. The stroke was induced by middle cerebral artery occlusion (MCAO) with subsequent reperfusion. Changes in the expression of 96 genes were examined using low-density expression arrays after MCAO alone and after MCAO combined with 1Hz, 5Hz, continuous (cTBS) and intermittent (iTBS) theta-burst rTMS. rTMS over the lesioned hemisphere was given for two weeks (with a 2-day pause) in a single daily session and a total of 2400 pulses. MCAO alone induced significant upregulation in the expression of 44 genes and downregulation in 10. Two weeks of iTBS induced significant increase in the expression of 52 genes. There were no downregulated genes. 1Hz and 5Hz had no significant effects on gene expression, while cTBS effects were negligible. Upregulated genes included those involved in angiogenesis, inflammation, injury response and cellular repair, structural remodeling, neuroprotection, neurotransmission and neuronal plasticity. The results show that long-term rTMS in acute ischemic-reperfusion brain injury induces complex changes in gene expression that span multiple pathways, which generally promote the recovery. They also demonstrate that induced changes primarily depend on the rTMS frequency (1Hz and 5Hz vs. iTBS) and pattern (cTBS vs. iTBS). The results further underlines the premise that one of the benefits of rTMS application in stroke may be to prime the brain, enhancing its potential to cope with the injury and to rewire. This could further augment its potential to favorably respond to rehabilitation, and to restore some of the loss functions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0139892PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4592250PMC
June 2016

Challenges and future directions in therapeutics for pancreatic ductal adenocarcinoma.

Expert Opin Investig Drugs 2014 Nov 31;23(11):1499-515. Epub 2014 Jul 31.

Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University , PO Box 17666, Al Ain , UAE.

Introduction: Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer death in the USA. The 5-year survival of < 5% has not changed in decades. In contrast to other major cancers, the incidence of PDAC is increasing.

Areas Covered: The aims of this paper are first to analyze why PDAC is so difficult to treat and, second, to suggest future directions for PDAC therapeutics. The authors provide an article that is based on a comprehensive search through MEDLINE and the clinicalTrials.gov website.

Expert Opinion: Progress has been made recently. Notably, FOLFIRINOX or nab-paclitaxel plus gemcitabine provide survival benefit over gemcitabine alone, which was previously the mainstay of therapy for PDAC. Most of the current trials are testing combinations of repurposed drugs rather than addressing key targets in the PDAC pathogenesis. It is clear that to really make an impact on this disease, it will be necessary to address three different problems with targeted therapeutics. First, it is important to eradicate PDAC stem cells that result in recurrence. Second, it is important to reduce the peritumoral stroma that provides the tumors with growth support and provides a barrier to access of therapeutic agents. Finally, it is important to address the marked cachexia and metabolic derangement that contribute to morbidity and mortality and further complicate therapeutic intervention.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1517/13543784.2014.933206DOI Listing
November 2014

Inhibitory Effects of Salinomycin on Cell Survival, Colony Growth, Migration, and Invasion of Human Non-Small Cell Lung Cancer A549 and LNM35: Involvement of NAG-1.

PLoS One 2013 21;8(6):e66931. Epub 2013 Jun 21.

Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.

A major challenge for oncologists and pharmacologists is to develop more potent and less toxic drugs that will decrease the tumor growth and improve the survival of lung cancer patients. Salinomycin is a polyether antibiotic used to kill gram-positive bacteria including mycobacteria, protozoans such as plasmodium falciparum, and the parasites responsible for the poultry disease coccidiosis. This old agent is now a serious anti-cancer drug candidate that selectively inhibits the growth of cancer stem cells. We investigated the impact of salinomycin on survival, colony growth, migration and invasion of the differentiated human non-small cell lung cancer lines LNM35 and A549. Salinomycin caused concentration- and time-dependent reduction in viability of LNM35 and A549 cells through a caspase 3/7-associated cell death pathway. Similarly, salinomycin (2.5-5 µM for 7 days) significantly decreased the growth of LNM35 and A549 colonies in soft agar. Metastasis is the main cause of death related to lung cancer. In this context, salinomycin induced a time- and concentration-dependent inhibition of cell migration and invasion. We also demonstrated for the first time that salinomycin induced a marked increase in the expression of the pro-apoptotic protein NAG-1 leading to the inhibition of lung cancer cell invasion but not cell survival. These findings identify salinomycin as a promising novel therapeutic agent for lung cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0066931PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3689654PMC
October 2017

Frondoside a suppressive effects on lung cancer survival, tumor growth, angiogenesis, invasion, and metastasis.

PLoS One 2013 8;8(1):e53087. Epub 2013 Jan 8.

Department of Pharmacology & Therapeutics, Faculty of Medicine & Health Sciences, U. A. E. University, Al-Ain, United Arab Emirates.

A major challenge for oncologists and pharmacologists is to develop less toxic drugs that will improve the survival of lung cancer patients. Frondoside A is a triterpenoid glycoside isolated from the sea cucumber, Cucumaria frondosa and was shown to be a highly safe compound. We investigated the impact of Frondoside A on survival, migration and invasion in vitro, and on tumor growth, metastasis and angiogenesis in vivo alone and in combination with cisplatin. Frondoside A caused concentration-dependent reduction in viability of LNM35, A549, NCI-H460-Luc2, MDA-MB-435, MCF-7, and HepG2 over 24 hours through a caspase 3/7-dependent cell death pathway. The IC50 concentrations (producing half-maximal inhibition) at 24 h were between 1.7 and 2.5 µM of Frondoside A. In addition, Frondoside A induced a time- and concentration-dependent inhibition of cell migration, invasion and angiogenesis in vitro. Frondoside A (0.01 and 1 mg/kg/day i.p. for 25 days) significantly decreased the growth, the angiogenesis and lymph node metastasis of LNM35 tumor xenografts in athymic mice, without obvious toxic side-effects. Frondoside A (0.1-0.5 µM) also significantly prevented basal and bFGF induced angiogenesis in the CAM angiogenesis assay. Moreover, Frondoside A enhanced the inhibition of lung tumor growth induced by the chemotherapeutic agent cisplatin. These findings identify Frondoside A as a promising novel therapeutic agent for lung cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0053087PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3540099PMC
July 2013

Frondoside A inhibits human breast cancer cell survival, migration, invasion and the growth of breast tumor xenografts.

Eur J Pharmacol 2011 Oct 27;668(1-2):25-34. Epub 2011 Jun 27.

Department of Pharmacology & Therapeutics, Faculty of Medicine & Health Sciences, UAE University, Al-Ain, PO Box: 17666, United Arab Emirates.

Breast cancer is a major challenge for pharmacologists to develop new drugs to improve the survival of cancer patients. Frondoside A is a triterpenoid glycoside isolated from the sea cucumber, Cucumaria frondosa. It has been demonstrated that Frondoside A inhibited the growth of pancreatic cancer cells in vitro and in vivo. We investigated the impact of Frondoside A on human breast cancer cell survival, migration and invasion in vitro, and on tumor growth in nude mice, using the human estrogen receptor-negative breast cancer cell line MDA-MB-231. The non-tumorigenic MCF10-A cell line derived from normal human mammary epithelium was used as control. Frondoside A (0.01-5 μM) decreased the viability of breast cancer cells in a concentration- and time-dependent manner, with 50%-effective concentration (EC50) of 2.5 μM at 24h. MCF10-A cells were more resistant to the cytotoxic effect of Frondoside A (EC50 superior to 5 μM at 24 h). In the MDA-MB-231 cells, Frondoside A effectively increased the sub-G1 (apoptotic) cell fraction through the activation of p53, and subsequently the caspases 9 and 3/7 cell death pathways. In addition, Frondoside A induced a concentration-dependent inhibition of MDA-MB-231 cell migration and invasion. In vivo, Frondoside A (100 μg/kg/dayi.p. for 24 days) strongly decreased the growth of MDA-MB-231 tumor xenografts in athymic mice, without manifest toxic side-effects. Moreover, we found that Frondoside A could enhance the killing of breast cancer cells induced by the chemotherapeutic agent paclitaxel. These findings identify Frondoside A as a promising novel therapeutic agent for breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ejphar.2011.06.023DOI Listing
October 2011

Structural lesions and changing pattern of expression of genes encoding cardiac muscle proteins are associated with ventricular myocyte dysfunction in type 2 diabetic Goto-Kakizaki rats fed a high-fat diet.

Exp Physiol 2011 Aug 10;96(8):765-77. Epub 2011 Jun 10.

Department of Physiology, Faculty of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.

Given the clinical prevalence of type 2 diabetes and obesity and their association with high mortality linked to cardiovascular disease, the aim of the study was to investigate the effects of feeding type 2 diabetic Goto-Kakizaki (GK) rats either high- or low-fat diets on cardiomyocyte structure and function. The GK rats were fed either a high-fat diet (HFD) or a low-fat diet (LFD) from the age of 2 months for a period of 7 months. The GK-HFD rats gained more weight, ate less food and drank less water compared with GK-LFD rats. At 7 months, non-fasting blood glucose was higher in GK-LFD (334 ± 35 mg dl(-1)) compared with GK-HFD rats (235 ± 26 mg dl(-1)). Feeding GK rats with a HFD had no significant effect on glucose clearance following a glucose challenge. Time-to-peak (t(peak)) shortening was reduced in myocytes from GK-HFD (131.8 ± 2.1 ms) compared with GK-LFD rats (144.5 ± 3.0 ms), and time-to-half (t(1/2)) relaxation of shortening was also reduced in myocytes from GK-HFD (71.7 ± 6.9 ms) compared with GK-LFD rats (86.1 ± 3.6 ms). The HFD had no significant effect on the amplitude of shortening. The HFD had no significant effect on t(peak), t(1/2) decay, amplitude of the Ca(2+) transient, myofilament sensitivity to Ca(2+), sarcoplasmic reticulum Ca(2+) content, fractional release of Ca(2+) and the rate of Ca(2+) uptake. Structurally, ventricular myocytes from GK-HFD rats showed extensive mitochondrial lesions, including swelling, loss of cristae, and loss of inner and outer membranes, resulting in gross vacuolarization and deformation of ventricular mitochondria with a subsequent reduction in mitochondrial density. Expression of genes encoding various L-type Ca(2+) channel proteins (Cacnb2) and cardiac muscle proteins (Myl2 and Atp2a1) were downregulated in GK-HFD compared with GK-LFD rats. Structural lesions and changed expression of genes encoding various cardiac muscle proteins might partly underlie the altered time course of myocyte shortening and relaxation in myocytes from GK-HFD compared with GK-LFD rats.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1113/expphysiol.2011.058446DOI Listing
August 2011

Alteration of strain background and a high omega-6 fat diet induces earlier onset of pancreatic neoplasia in EL-Kras transgenic mice.

Int J Cancer 2011 Jun 26;128(12):2783-92. Epub 2010 Oct 26.

Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.

Diets containing omega-6 (ω-6) fat have been associated with increased tumor development in carcinogen-induced pancreatic cancer models. However, the effects of ω-6 fatty acids and background strain on the development of genetically-induced pancreatic neoplasia is unknown. We assessed the effects of a diet rich in ω-6 fat on the development of pancreatic neoplasia in elastase (EL)-Kras(G12D) (EL-Kras) mice in two different backgrounds. EL-Kras FVB mice were crossed to C57BL/6 (B6) mice to produce EL-Kras FVB6 F1 (or EL-Kras F1) and EL-Kras B6 congenic mice. Age-matched EL-Kras mice from each strain were compared to one another on a standard chow. Two cohorts of EL-Kras FVB and EL-Kras F1 mice were fed a 23% corn oil diet and compared to age-matched mice fed a standard chow. Pancreata were scored for incidence, frequency, and size of neoplastic lesions, and stained for the presence of mast cells to evaluate changes in the inflammatory milieu secondary to a high fat diet. EL-Kras F1 mice had increased incidence, frequency, and size of pancreatic neoplasia compared to EL-Kras FVB mice. The frequency and size of neoplastic lesions and the weight and pancreatic mast cell densities in EL-Kras F1 mice were increased in mice fed a high ω-6 fatty acid diet compared to mice fed a standard chow. We herein introduce the EL-Kras B6 mouse model which presents with increased frequency of pancreatic neoplasia compared to EL-Kras F1 mice. The phenotype in EL-Kras F1 and FVB mice is promoted by a diet rich in ω-6 fatty acid.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ijc.25622DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3061970PMC
June 2011

Risk of blood-borne infections in barber shops.

J Infect Public Health 2010 26;3(2):88-9. Epub 2010 May 26.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jiph.2010.03.001DOI Listing
November 2010

Anti-pancreatic cancer effects of a polar extract from the edible sea cucumber, Cucumaria frondosa.

Pancreas 2010 Jul;39(5):646-52

Department of Surgery and Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.

Objectives: To investigate the effects and mechanism of Frondanol-A5P, a polar extract from Cucumaria frondosa, on growth inhibition and apoptosis in S2013 and AsPC-1 human pancreatic cancer cells.

Methods: The effects of Frondanol-A5P on proliferation, cell cycle, expression of cell cycle proteins and p21, phosphorylation of MAP kinases, annexin V binding, and caspase-3 activation were examined.

Results: Frondanol-A5P inhibited proliferation and induced G2/M phase cell cycle arrest in both cell lines with decreased expression of cyclin A, cyclin B, and cdc25c. Frondanol-A5P induced phosphorylation of stress-activated protein kinase and Janus kinase (SAPK/JAK) and p38 mitogen-activated protein kinase (MAP) within 5 minutes. Frondanol-A5P markedly increased expression of p21 messenger RNA and protein at 3 hours in both cell lines. This effect was reduced by the p38 kinase inhibitor, SB203580. Frondanol-A5P markedly increased annexin V binding and activated caspase-3.

Conclusions: Frondanol-A5 causes cell cycle arrest and apoptosis in human pancreatic cancer cells. These changes are associated with decreased expression of cyclin A, cyclin B, and cdc25c and increased expression of p21 that, at least in part, is mediated by a p38 kinase-dependent mechanism. Because Frondanol-A5P is derived from an edible, nontoxic, sea cucumber, it may be valuable for nutritional therapy or prevention of pancreatic cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MPA.0b013e3181c72bafDOI Listing
July 2010

A high omega-3 fatty acid diet mitigates murine pancreatic precancer development.

J Surg Res 2011 Jan 15;165(1):75-81. Epub 2009 May 15.

Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA.

Background: Diets containing omega-3 (ω-3) fat have been associated with decreased tumor development in the colon, breast, and prostate. We assessed the effects of a diet rich in ω-3 fat on the development of pancreatic precancer in elastase (EL)-Kras transgenic mice and examined the effect of an ω-3 fatty acid on pancreatic cancer cells in vitro.

Materials And Methods: Two cohorts of EL-Kras mice were fed a high ω-3 fat diet (23% menhaden oil) for 8 and 11 mo and compared with age-matched EL-Kras mice fed standard chow (5% fat). Pancreata from all mice were scored for incidence and frequency of precancerous lesions. Immunohistochemistry was performed for proliferating cell nuclear antigen (PCNA) to assess proliferative index in lesions of mice fed either a high ω-3 or standard diet. In vitro, the effect of the ω-3 fatty acid, docosahexaenoic acid (DHA), on two pancreatic cancer cell lines was assessed. Cancer cell proliferation was assessed with an MTT assay; cell cycle analysis was performed by flow cytometry; and apoptosis was assessed with annexin/PI staining.

Results: The incidence, frequency, and proliferative index of pancreatic precancer in EL-Kras mice was reduced in mice fed a high ω-3 fat diet compared with mice fed a standard chow. In vitro, DHA treatment resulted in a concentration-dependent decrease in proliferation through both G1/G0 cell cycle arrest and induction of apoptosis.

Conclusions: A high ω-3 fat diet mitigates pancreatic precancer by inhibition of cellular proliferation through induction of cell cycle arrest and apoptosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jss.2009.04.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2888718PMC
January 2011

The Role of PPARgamma Receptors and Leukotriene B(4) Receptors in Mediating the Effects of LY293111 in Pancreatic Cancer.

PPAR Res 2008 27;2008:827096. Epub 2009 Jan 27.

Department of Physiology, Faculty of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.

Pancreatic cancer is a devastating disease in which current therapies are inadequate. Separate lines of research have identified the 5-lipoxygenase/leukotriene B(4) receptor pathway and the PPARgamma pathway as potential targets for prevention or treatment of this disease. LY293111 was originally designed as a potent leukotriene B(4) receptor antagonist for treatment of inflammatory conditions. LY293111 was also known to have inhibitory effects on 5-lipoxygenase, which is upstream of the production of leukotrienes. LY293111 was shown to have potent anticancer effects in pancreatic cancer and several other solid malignancies, where it caused cell cycle arrest and marked apoptosis. Subsequently, it came to light that LY293111 exhibited PPARgamma agonist activity in addition to its effects on the 5-lipoxygenase pathway. This raises the question of which of the two targets is of greatest importance with regard to the anticancer effects of this agent. The evidence to date is not conclusive, but suggests that the effects of LY293111 may be mediated by both LTB(4) receptors and PPARgamma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2008/827096DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2631651PMC
July 2011

On the role of transforming growth factor-beta in the growth inhibitory effects of retinoic acid in human pancreatic cancer cells.

Mol Cancer 2007 Dec 24;6:82. Epub 2007 Dec 24.

Department of Surgery and Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.

Background: Retinoids are potent growth inhibitory and differentiating agents in a variety of cancer cell types. We have shown that retinoids induce growth arrest in all pancreatic cancer cell lines studied, regardless of their p53 and differentiation status. However, the mechanism of growth inhibition is not known. Since TGF-beta2 is markedly induced by retinoids in other cancers and mediates MUC4 expression in pancreatic cancer cells, we investigated the role of TGF-beta in retinoic acid-mediated growth inhibition in pancreatic cancer cells.

Results: Retinoic acid markedly inhibited proliferation of two cell lines (Capan-2 and Hs766T) in a concentration and time-dependent manner. Retinoic acid increased TGF-beta2 mRNA content and secretion of the active and latent forms of TGF-beta2 (measured by ELISA and bioassay). The concentrations of active and TGF-beta2 secreted in response to 0.1 - 10 muM retinoic acid were between 1-5 pM. TGF-beta2 concentrations within this range also inhibited proliferation. A TGF-beta neutralizing antibody blocked the growth inhibitory effects of retinoic acid in Capan-2 cells and partially inhibitory the effects in Hs766T cells.

Conclusion: These findings indicate that TGF-beta can cause growth inhibition of pancreatic cancer cells, in a p53-independent manner. Furthermore, it demonstrates the fundamental role of TGF-beta in growth inhibition in response to retinoic acid treatment is preserved in vitro.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/1476-4598-6-82DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2248210PMC
December 2007

Novel marine-derived anti-cancer agents.

Authors:
Thomas E Adrian

Curr Pharm Des 2007 ;13(33):3417-26

Department of Physiology, United Arab Emirates University, PO Box 17666, Al Ain, United Arab Emirates.

There is an immense diversity of marine plants and animals from which an estimated 14,000 pharmacologically active compounds have been isolated. However, in terms of clinically useful anti-cancer agents, the oceans remain as a largely untapped resource. Indeed, there are currently only two compounds used in the clinic that are derived from marine sources. These are cytarabine, which is a deoxycitidine analogue and aplidine, which has both growth inhibitory and anti-angiogenic effects. This situation is likely to change rather dramatically in the near future, as attention has focused on the vast diversity of available agents from marine organisms. The increased pace of activity in this area has resulted in a several clinical trials of promising compounds with the probability that these will be followed by other drugs currently under preclinical development.
View Article and Find Full Text PDF

Download full-text PDF

Source
February 2008

15-lipoxygenase-1 production is lost in pancreatic cancer and overexpression of the gene inhibits tumor cell growth.

Neoplasia 2007 Nov;9(11):917-26

Department of Surgery, Technische Universität München, Munich, Germany.

Pancreatic cancer patients have an abysmal prognosis because of late diagnosis and lack of therapeutic options. Pancreatic intraepithelial neoplasias (PanINs), the precursor lesions, are a potential target for chemoprevention. Targeting eicosanoid pathways is an obvious choice because 5-lipoxygenase (5-LOX) has been suggested as a tumor promoter in pancreatic carcinogenesis. Here we provide evidence that 15-lipoxygenase-1 (15-LOX-1) expression and activity may exert antitumorigenic effects in pancreatic cancer. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis showed absence or very weak expression of 15-LOX-1 in all pancreatic cancer cell lines tested. 15-LOX-1 was strongly stained in normal ductal cells, tubular complexes, and centroacinar cells, but no staining was seen in islets, cancer cells, PanIN lesions, or in tumor cells in lymph node metastases, indicating that 15-LOX-1 expression is lost during tumor development in human pancreas. Overexpression of 15-LOX-1 in pancreatic tumor cells or treatment with its arachidonic acid-derived metabolite resulted in decreased cell growth. These findings provide evidence that loss of 15-LOX-1 may play an important role in pancreatic carcinogenesis, possibly as a tumor suppressor gene. Thus, induction of 15-LOX-1 expression may be an attractive option for the prevention and treatment of pancreatic cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2077883PMC
http://dx.doi.org/10.1593/neo.07565DOI Listing
November 2007

Leukotriene B4 receptor antagonist LY293111 induces S-phase cell cycle arrest and apoptosis in human pancreatic cancer cells.

Anticancer Drugs 2007 Jun;18(5):535-41

Department of Surgery, Robert H. Lurie Comprehensive Cancer Center, Northwestern University School of Medicine, Chicago, Illinois 60611, USA.

We have previously shown that the leukotriene B4 receptor antagonist, LY293111 inhibits proliferation and induces apoptosis in human pancreatic cancer cells both in vitro and in vivo. In the current study, we investigated the molecular mechanisms of LY293111-induced apoptosis and cell cycle arrest. Two human pancreatic cancer cell lines were used in this study, MiaPaCa-2 and AsPC-1. Cell cycle analysis by flow cytometry showed a dramatic increase in the percentage of apoptotic cells as well as S-phase arrest after treatment with 250 nmol/l LY293111 for up to 48 h. Western blotting indicated that LY293111 treatment induced cytochrome c release from the mitochondria into the cytosol, accompanied by caspase-9, caspase-7 and caspase-3 activation, and cleavage of poly ADP-ribose polymerase. Caspase-8 was not activated by LY293111. A decrease was found in the expression of the antiapoptotic proteins, Bcl-2 and Mcl-1, and an increase in the proapoptotic protein, Bax. LY293111 reduced the expression of CDK2, cyclin A and cyclin E, consistent with the S-phase arrest observed in these cells. The expression of cyclin-dependent kinase inhibitors, p21 and p27 was not affected by LY293111 treatment. In conclusion, LY293111 induces apoptosis in human pancreatic cancer cells through the mitochondria-mediated pathway. LY293111 also induces S-phase arrest with downregulation of CDK2, cyclin A and cyclin E. Blockade of leukotriene B4 metabolic pathway may provide a novel treatment for human pancreatic cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/01.cad.0000231477.22901.8aDOI Listing
June 2007

Resveratrol inhibits pancreatic cancer cell proliferation through transcriptional induction of macrophage inhibitory cytokine-1.

J Surg Res 2007 Apr 25;138(2):163-9. Epub 2007 Jan 25.

Department of Surgery, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA.

Introduction: Resveratrol is a phenolic compound found in grape skins, mulberries, and certain nuts that has been shown to have antitumorigenic and anti-inflammatory properties. Macrophage inhibitory cytokine (MIC-1) is a member of the transforming growth factor beta (TGF-beta) superfamily that has been shown to have antitumorigenic activity and is up-regulated in resveratrol-treated cancer cells. Resveratrol inhibits proliferation of human pancreatic cancer cells; however, the exact mechanism of action is not known. In this study, we investigated the role of MIC-1 in resveratrol-induced growth inhibition of human pancreatic cancer cell lines.

Methods And Results: Proliferation assays conducted with resveratrol-treated human pancreatic cancer cell lines (CD18 and S2-013) at 24, 48, and 72 h revealed inhibition of cell proliferation compared to controls. Using oligonucleotide microarray analysis, we identified marked up-regulation of MIC-1 gene expression in resveratrol-treated human pancreatic cancer S2-013 cells. Real-time RT-PCR performed in CD18 and S2-013 cells treated with resveratrol (0-100 mum) for 24 h confirmed concentration and time-dependent up-regulation of expression of one particular gene, MIC-1. Both cell lines pretreated with actinomycin D (a transcriptional inhibitor) and then resveratrol had reduced up-regulation of MIC-1 gene expression compared to those treated with resveratrol alone. Finally, resveratrol-induced growth inhibition was abolished in CD18 cells transfected with MIC-1 short interfering RNA.

Conclusions: Resveratrol up-regulates MIC-1 gene expression in part at the transcriptional level in pancreatic cancer cells. Furthermore, MIC-1 appears to play a key role in resveratrol-induced growth inhibition in these cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jss.2006.05.037DOI Listing
April 2007

Apigenin inhibits pancreatic cancer cell proliferation through G2/M cell cycle arrest.

Mol Cancer 2006 Dec 29;5:76. Epub 2006 Dec 29.

Department of Surgery and Robert H, Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.

Background: Many chemotherapeutic agents have been used to treat pancreatic cancer without success. Apigenin, a naturally occurring flavonoid, has been shown to inhibit growth in some cancer cell lines but has not been studied in pancreatic cancer. We hypothesized that apigenin would inhibit pancreatic cancer cell growth in vitro.

Results: Apigenin caused both time- and concentration-dependent inhibition of DNA synthesis and cell proliferation in four pancreatic cancer cell lines. Apigenin induced G2/M phase cell cycle arrest. Apigenin reduced levels of cyclin A, cyclin B, phosphorylated forms of cdc2 and cdc25, which are all proteins required for G2/M transition.

Conclusion: Apigenin inhibits growth of pancreatic cancer cells through suppression of cyclin B-associated cdc2 activity and G2/M arrest, and may be a valuable drug for the treatment or prevention of pancreatic cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/1476-4598-5-76DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1779363PMC
December 2006

On the mechanisms of 12-O-tetradecanoylphorbol-13-acetate-induced growth arrest in pancreatic cancer cells.

Pancreas 2006 Aug;33(2):148-55

Department of Surgery and Robert H Lurie Cancer Center, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA.

Objectives: Protein kinase C (PKC) is involved in cell growth, differentiation, and apoptosis. We investigated the effects of the PKC activator, the tetradecanylphorbol acetate (TPA), in human pancreatic cancer cells.

Methods: Cell proliferation was measured by thymidine incorporation. Expression of cell cycle proteins was investigated by Western blot. Real-time reverse transcriptase-polymerase chain reaction was used to measure p21 messenger RNA expression, whereas knockdown of its expression was accomplished with a specific small interferring RNA. Cell cycle phases were determined by flow cytometry.

Results: TPA time and concentration dependently inhibited thymidine incorporation in Panc-1 and CD18 cells and induced G2/M cell cycle arrest. The TPA decreased cyclin A and B expression, increased cyclin E, and markedly increased the expression of p21 at both the messenger RNA and protein levels. TPA-induced p21 expression and growth inhibition were blocked by the PKC inhibitor, bisindoylmaleimide. TPA induced extracellular signal-regulated kinase1/2 phosphorylation, whereas the MEK inhibitor, PD98059, blocked the TPA-induced p21 expression. Small interferring RNA targeted to p21 blocked TPA-induced p21 protein expression but not TPA-induced cell growth arrest.

Conclusions: TPA-induced p21 expression is mediated by the MEK/ERK pathway but is not involved in TPA-induced growth inhibition. In contrast, cyclin A and cyclin B are likely involved in TPA-induced G2/M arrest because both proteins are involved in S phase and G2/M transition during cell proliferation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/01.mpa.0000226896.93945.41DOI Listing
August 2006

A novel peptide sansalvamide analogue inhibits pancreatic cancer cell growth through G0/G1 cell-cycle arrest.

Biochem Biophys Res Commun 2006 Feb 5;340(4):1224-8. Epub 2006 Jan 5.

Robert H Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.

Patients with pancreatic cancer have little hope for cure because no effective therapies are available. Sansalvamide A is a cyclic depsipeptide produced by a marine fungus. We investigated the effect of a novel sansalvamide A analogue on growth, cell-cycle phases, and induction of apoptosis in human pancreatic cancer cells in vitro. The sansalvamide analogue caused marked time- and concentration-dependent inhibition of DNA synthesis and cell proliferation of two human pancreatic cancer cell lines (AsPC-1 and S2-013). The analogue induced G0/G1 phase cell-cycle arrest and morphological changes suggesting induction of apoptosis. Apoptosis was confirmed by annexin V binding. This novel sansalvamide analogue inhibits growth of pancreatic cancer cells through G0/G1 arrest and induces apoptosis. Sansalvamide analogues may be valuable for the treatment of pancreatic cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2005.12.131DOI Listing
February 2006