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Research Interests: Cytokines, Immunohistochemistry, Experimental Design, Medicine, Humans, and 15 moreCurcumin, Female, Male, Methane, Aged, Middle Aged, Cytokine, Adult, Disease Progression, Biological activity, Food and Drug Administration, Antineoplastic Agents, Adenocarcinoma, biological effect, and Cyclooxygenase
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Branched-chain fatty acids or fatty alcohols have been reported to possess anti-tumor activity in various tumor models. Here we study 12-methyltetradecanoic acid (12-MTA), a branched-chain fatty acid, isolated from a sea cucumber extract,... more
Branched-chain fatty acids or fatty alcohols have been reported to possess anti-tumor activity in various tumor models. Here we study 12-methyltetradecanoic acid (12-MTA), a branched-chain fatty acid, isolated from a sea cucumber extract, on the growth of prostate cancer cells and investigate the underlying mechanisms of its effect. 12-MTA was evaluated by MTT assay for its ability to inhibit cell proliferation in various cancer types. The ability of 12-MTA to induce apoptosis of PC3 cells was examined by morphologic changes, propidium iodide (PI) staining, and caspase-3 activation. Furthermore, alteration of eicosanoid metabolism by 12-MTA was examined in PC3 and RBL-1 cells and in purified lipoxygenase (LOX) and cyclooxygenase (COX) enzymes. 12-MTA inhibited proliferation of various cell lines, with IC50s ranging from 17.99 to 35.44 microg/ml. PI staining clearly showed that 12-MTA caused PC3 cell death through induction of apoptosis. At 50 microg/ml, 12-MTA increased caspase-3 activity four to seven-fold compared with that in control cells. Examination of cellular arachidonate metabolism showed that at 25 microg/ml, 12-MTA reduced the level of 5-hydroxyeicosatetraenoic acid (5-HETE) by 45%. Furthermore, exogenous 5-HETE protects PC3 cells from 12-MTA induced cell death. 12-MTA inhibited proliferation of cancer cells via apoptosis, in which caspase-3 may play a role. At relevant concentrations, 12-MTA can selectively inhibit the formation of 5-HETE, a metabolite of 5-lipoxygenase. This agent may be a novel adjunctive therapy for selected malignancies including prostate cancer.
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Fifth AACR International Conference on Frontiers in Cancer Prevention Research, Nov 12-15, 2006 A80 We continue to explore extracts and pure molecules derived from the holothurian (sea cucumber) Cucumaria frondosa . With support from the... more
Fifth AACR International Conference on Frontiers in Cancer Prevention Research, Nov 12-15, 2006 A80 We continue to explore extracts and pure molecules derived from the holothurian (sea cucumber) Cucumaria frondosa . With support from the NCI's RAPID Program, we investigated Frondanol® A5, for indications of therapeutic and preventive effects against cancer. We have shown that Frondanol A5 and its glycoside components inhibit growth of pancreatic cancer cells through induction of apoptosis. Research indicated that Frondanol® A5 mediated cell death was associated with an increase in p-21Cip1, phosphorylation of p38 kinase, and triggered the apoptotic caspase cascade. Isolated crude glycosides from Frondanol A5 were found to inhibit COX-1 and COX-2 in a conc.-dependent manner, while the non-saponifiable fraction from Frondanol® A5 exhibited strong inhibition of the 5-lipoxygenase pathway. We have also previously shown that glycosides of Frondanol® A5 appear to block the G-coupled prostaglandin EP-1 receptor and show an inhibitory activity in an arachidonic acid-induced mouse ear inflammation model. We now show that in a DMBA Mouse Mammary Organ Culture assay, Frondanol A5 inhibits development of breast cancer ductal lesions by 75% using very low drug conc. In the B[ a ]P-induced Rat Tracheal Epithelial foci inhibition assay, Frondanol® A5 significantly inhibited (86.4% decrease) transformation at 0.3 u g/ml. A 98% pure glycoside component of Frondanol® A5, designated Frondoside A, inhibited microtubule formation by 88% (at 1 u M) in a HUVEC based angiogenesis assay. Pure Frondoside A has also been shown to have immunomodulatory effects. Frondoside A, was injected subcutaneously to Staph. aureus infected mice. Saline controls showed 10% survival, while Frondoside A treated mice showed 40% survival which was considered to be a significant survival improvement in this difficult test. Finally, microarray analyses of the effect of Frondoside A in the pancreatic cancer cell line S2-013 has shown increased expression of anti-oxidant genes associated with modulation of free radical damage (SOD and AKR1C1) and down-regulation of several pro-inflammatory genes and genes involved in cyclin dependent kinase pathways. Our data thus indicate the multi-mechanistic potential of Frondanol® A5 and its subcomponent glycoside Frondoside A as potentially useful novel chemopreventive agents. As a popular Oriental delicacy for more than 1,000 years, we suggest that sea cucumber glycosidic compounds are a safe cancer nutrapreventive food supplement with pronounced beneficial effects in biochemical and genomic pathways now known to contribute to cancer initiation, progression and metastatic pathology. This has been supported by the National Cancer Institute, Division of Chemoprevention RAPID Program, American Institute for Cancer Research, Maine Technology Institute and the Russian Academy of Science in Vladivostok, Russia.
Research Interests: Biology and Angiogenesis
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Research Interests: Chemistry, Cancer, Membrane Proteins, Apoptosis, Medicine, and 15 moreColorectal cancer, Western blotting, Antioxidants, Cell line, Humans, Time Factors, Colon cancer, Isoenzymes, Recombinant Proteins, Antineoplastic Agents, Arachidonic Acid, Linoleic Acid, Sulfonamides, Nonsteroidal Anti-inflammatory Drug, and Colonic Neoplasms
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.... more
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 evide...
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Peplomycin, an antitumour antibiotic analogue of bleomycin, was measured in mouse tissues using a rapid radioimmunoassay. Antiserum, obtained by immunizing rabbits with peplomycin-bovine serum albumin conjugate, showed no significant... more
Peplomycin, an antitumour antibiotic analogue of bleomycin, was measured in mouse tissues using a rapid radioimmunoassay. Antiserum, obtained by immunizing rabbits with peplomycin-bovine serum albumin conjugate, showed no significant cross-reactivity with the closely related peplomycin analogues bleomycin and liblomycin, nor with a number of other structurally unrelated antitumour drugs. The assay is sensitive and can detect peplomycin levels as low as 2 ng ml-1. The relative intra- and inter-assay standard deviation is < or = 5%, indicating good assay reproducibility. Peplomycin levels in mouse tissues were easily determined without extraction. Fifteen minutes after administration of a single intraperitoneal dose of peplomycin at 8.5 mg kg-1 (1/10 of LD50), high drug levels were found in plasma (46 micrograms ml-1), kidneys (38 micrograms g-1), urine and bladder (32 micrograms ml-1), followed by gastrointestinal tract (13 micrograms g-1), lung (8 micrograms g-1), spleen (3.7 micrograms g-1), heart (3.6 micrograms g-1), gall bladder (2.7 micrograms g-1), liver (2 micrograms g-1), and brain (0.6 microgram g-1). The total amount of drug in all these organs accounted for more than 80% of the dose administered. We conclude that the radioimmunoassay is sensitive and reproducible and is an ideal tool for measuring peplomycin in tissues and biofluids for pharmacological studies.
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Research Interests: Mitochondria, Apoptosis, Signal Transduction, Mitosis, Humans, and 13 moreGlioma, Anthozoa, Mice, Female, Animals, Caribbean region, Diterpenes, Malignant Glioma, Molecular Cancer Therapeutics, Antineoplastic Agents, Protein Transport, Minimum inhibitory concentration, and Pharmacology and pharmaceutical sciences
To evaluate a blend of two natural ingredients on immune parameters relevant for their current topical use and potential support of microcirculation in skin tissue. A blend (BL) of Aloe vera-based Nerium oleander extract (NAE-8i,... more
To evaluate a blend of two natural ingredients on immune parameters relevant for their current topical use and potential support of microcirculation in skin tissue. A blend (BL) of Aloe vera-based Nerium oleander extract (NAE-8i, oleandrin-free) and hydrolyzed water-soluble egg membrane (WSEM) was applied to human whole-blood cultures for 24 hours, with each separate ingredient serving as a control. Immune-cell subsets were analyzed for expression levels of the activation markers CD69 and CD25. Culture supernatants were analyzed for cytokines, chemokines, and immunoregulating peptides. BL increased CD69 expression on lymphocytes, monocytes, and CD3(-)CD56(+) natural killer cells, and CD25 expression on natural killer cells. The number of CD69(+)CD25(+) lymphocytes increased in cultures treated with BL and the separate ingredients. BL triggered production of multiple cytokines and chemokines, where CC chemokines MIP1α and MIP3α, as well as cytokines involved in wound healing - Groα, ...
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Cardiac glycosides such as digitoxin and ouabain have previously been shown to be selectively cytotoxic to tumor as opposed to normal cells. Moreover, this class of agents has also been shown to act as potent radiosensitizers. In the... more
Cardiac glycosides such as digitoxin and ouabain have previously been shown to be selectively cytotoxic to tumor as opposed to normal cells. Moreover, this class of agents has also been shown to act as potent radiosensitizers. In the present study we explored the relative radiosensitization potential of oleandrin, a cardiac glycoside contained within the plant extract known as Anvirzele that
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We previously reported neuroprotective activity of the botanical anti-cancer drug candidate PBI-05204, a supercritical CO2 extract of Nerium oleander, in brain slice and in vivo models of ischemic stroke. We showed that one component of... more
We previously reported neuroprotective activity of the botanical anti-cancer drug candidate PBI-05204, a supercritical CO2 extract of Nerium oleander, in brain slice and in vivo models of ischemic stroke. We showed that one component of this neuroprotective activity is mediated through its principal cardiac glycoside constituent, oleandrin, via induction of the potent neurotrophic factor brain-derived neurotrophic factor (BDNF). However, we also noted that the concentration-relation for PBI-05204 in the brain slice oxygen-glucose deprivation (OGD) model is considerably broader than that for oleandrin as a single agent. We thus surmised that PBI-05204 contains an additional neuroprotective component(s), distinct from oleandrin. We report here that neuroprotective activity is also provided by the triterpenoid constituents of PBI-05204, notably oleanolic acid. We demonstrate that a sub-fraction of PBI-05204 (Fraction 0-4) containing oleanolic and other triterpenoids, but without cardia...
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LY195448(R) (a phenethanolamine derivative that has demonstrated cytotoxic activity against cell cultures in vitro but that exhibited a hypotensive side effect during phase I trials), its p-hydroxy and acid metabolites, and a noncytotoxic... more
LY195448(R) (a phenethanolamine derivative that has demonstrated cytotoxic activity against cell cultures in vitro but that exhibited a hypotensive side effect during phase I trials), its p-hydroxy and acid metabolites, and a noncytotoxic S-stereoisomer were evaluated with respect to competitive binding against the beta-adrenergic antagonist [3H]dihydroalprenolol in rat brain cortex and human cardiac tissues. When IC50 and Ki values were compared, the R-isomer of LY195448 in general was more potent than the S-stereoisomer. While LY195448(R) was about 10-fold more active than the p-hydroxy metabolite in cardiac tissues, the two compounds were nearly equipotent both in blocking the binding of radioligand to the brain and in reducing blood pressure in rats. In the cerebral preparation, the binding of the acid metabolite was weak, with its activity being equal to that of the S-stereoisomer.
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The goal for this study was to evaluate the effects of an Aloe vera-based Nerium oleander extract (NAE-8(®)), compared to an extract of A. vera gel alone (ALOE), and to an aqueous extract of N. oleander (AQ-NOE) in bioassays pertaining to... more
The goal for this study was to evaluate the effects of an Aloe vera-based Nerium oleander extract (NAE-8(®)), compared to an extract of A. vera gel alone (ALOE), and to an aqueous extract of N. oleander (AQ-NOE) in bioassays pertaining to dermatologic potential with respect to antioxidant protection, anti-inflammatory effects, and cytokine profiles in vitro. Cellular antioxidant protection was evaluated in three separate bioassays: The cellular antioxidant protection of erythrocytes (CAP-e) assay, protection of cellular viability and prevention of apoptosis, and protection of intracellular reduced glutathione levels, where the last two assays were performed using human primary dermal fibroblasts. Reduction of intracellular formation of reactive oxygen species (ROS) was tested using polymorphonuclear cells in the absence and presence of oxidative stress. Changes to cytokine and chemokine profiles when whole blood cells and human primary dermal fibroblasts were exposed to test product...
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Malignant gliomas continue to be a significant source of mortality in young and middle aged adults. The introduction of new treatment strategies and multidisciplinary approaches has improved the outcome of patients with these tumors only... more
Malignant gliomas continue to be a significant source of mortality in young and middle aged adults. The introduction of new treatment strategies and multidisciplinary approaches has improved the outcome of patients with these tumors only slightly. Because retinoic acid has growth inhibitory activity against glioma and neuroblastoma cells in cultures, we assessed the efficacy of all-trans-retinoic acid in the treatment of recurrent cerebral gliomas. Thirty-six patients with recurrent cerebral gliomas were entered in the study and treated with 120 or 150 mg/ m2/day of all-trans-retinoic acid as a single agent. The drug was given for 3 weeks followed with one week of rest. Two blocks of 4 weeks constituted one course of treatment. One (3%) of 34 evaluable patients had a minor response and 14 (41%) had stable disease. In the rest of the patients (56%), tumors continued to progress despite treatment. The median time to progression of all evaluable patients was 8 weeks, and for the respon...
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The effects of adenosine on the acute toxicity and oncolytic activity of adriamycin (ADR) were evaluated in mice. When administered as a single i.p. injection of 17.5 mg/kg, adriamycin produced death in all mice within 12 days after... more
The effects of adenosine on the acute toxicity and oncolytic activity of adriamycin (ADR) were evaluated in mice. When administered as a single i.p. injection of 17.5 mg/kg, adriamycin produced death in all mice within 12 days after treatment, with a mean survival time of 5-9 days. In contrast, the mean survival time of mice administered adenosine subcutaneously (200 mg/kg) in addition to adriamycin was significantly increased compared to adriamycin-treated mice. The protection elicited by adenosine was apparently not a generalized phenomenon of purines, however, since neither hypoxanthine nor inosine were effective protectants. Although a number of adenosine treatment schedules were tested, it was found that adenosine given immediately after adriamycin was as effective as multiple adenosine injections. Administration of adenosine had no apparent effect on adriamycin-mediated changes in ventricular weight, leukocyte count, elevated serum lactic dehydrogenase (LDH) activity or in the...
Research Interests: Pathology, Adenosine, Mice, Animals, Male, and 4 moreDoxorubicin, Time Factors, Body Weight, and Strains
Pulmonary fibrosis is a serious side effect that limits the therapeutic utility of bleomycin (BLM). Recently, it has been demonstrated that L-3, 4-dehydroproline (DHP), a proline analog, significantly reduced the extent of pulmonary... more
Pulmonary fibrosis is a serious side effect that limits the therapeutic utility of bleomycin (BLM). Recently, it has been demonstrated that L-3, 4-dehydroproline (DHP), a proline analog, significantly reduced the extent of pulmonary fibrosis in rats administered BLM intratracheally. The present studies were performed to determine the effect of DHP on the oncolytic and toxicologic effects of BLM. DHP (25 mg/kg/day) administered sc concomitantly with BLM (4 mg/kg/day) for 9 consecutive days following a sc inoculation of B16 melanoma cells in BDF1 had no effect on tumor growth inhibition by BLM when tumor growth rate was assessed by tumor volume and by tumor weight. To determine the effect of DHP on the toxicity of BLM, DHP (25 mg/kg/day) and BLM (10 mg/kg/day) were administered to Sprague-Dawley rats for 5 consecutive days followed by 2 days of rest and 5 additional days of drug administration. BLM administration produced decreased body weight gain, acute leukocytopenia, delayed eleva...
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Activity of the dipeptidyl hydrolase angiotensin-converting enzyme has been observed to be altered by treatment with bleomycin. We used an animal model of bleomycin lung toxicity to study the effects on angiotensin-converting enzyme... more
Activity of the dipeptidyl hydrolase angiotensin-converting enzyme has been observed to be altered by treatment with bleomycin. We used an animal model of bleomycin lung toxicity to study the effects on angiotensin-converting enzyme activity in various lung fractions. Serum activity of angiotensin-converting enzyme increased only 23% after a single intratracheal instillation of bleomycin. Lung tissue angiotensin-converting enzyme activity fell to 40% of control level (p < 0.05) and returned toward and eventually exceeded control values during the ensuing 6 weeks. However, angiotensin-converting enzyme activity in alveolar lavage fluid from bleomycin-treated rats was elevated 30-fold above the barely detectable levels found in control animals. Angiotensin-converting enzyme activity in lavage fluid was soluble and was not associated with the alveolar cell pellet. Maximum elevation of lavage angiotensin-converting enzyme activity occurred 3 days following bleomycin instillation. Sig...
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The effects of verapamil on the cytotoxicity and accumulation of multiple drugs were studied in a model of pleiotropic resistance generated by doxorubicin (DOX) selection of the human sarcoma cell line MES-SA. The in vitro sensitivity of... more
The effects of verapamil on the cytotoxicity and accumulation of multiple drugs were studied in a model of pleiotropic resistance generated by doxorubicin (DOX) selection of the human sarcoma cell line MES-SA. The in vitro sensitivity of the DOX-resistant variant (named Dx5), which is 50- to 100-fold resistant to DOX compared to MES-SA, was enhanced approximately 7-fold by verapamil (3 micrograms/ml). In addition, the cytotoxicity of several agents to which the Dx5 line displays cross-resistance, i.e., daunorubicin, dactinomycin, mitoxantrone, and etoposide, was also enhanced 2- to 14-fold by verapamil. These agents share the properties of DNA intercalation and/or interaction with topoisomerase II. In contrast, verapamil did not alter the sensitivity of Dx5 to several other agents to which cross-resistance had been demonstrated, i.e., vincristine, vinblastine, colchicine, mitomycin C, and melphalan; nor did verapamil enhance the cytotoxicity of DOX or other agents against the DOX-se...
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We compared the antitumor activity of cis-diamminedichloroplatinum(II) (cisplatin; CDDP) with three CDDP analogues: cis-diammine-1,1-cyclobutanedicarboxylateplatinum(II) (CBDCA), N-methyliminodiacetato-1,2-diamino(cyclohexane)platinum(II)... more
We compared the antitumor activity of cis-diamminedichloroplatinum(II) (cisplatin; CDDP) with three CDDP analogues: cis-diammine-1,1-cyclobutanedicarboxylateplatinum(II) (CBDCA), N-methyliminodiacetato-1,2-diamino(cyclohexane)platinum(II) (MIDP), and N-(2-hydroxyethyl)-iminodiacetato-1,2-diamino(cyclohexane)platinum (II) (HIDP). Fresh human tumor samples in the adhesive tumor culture system were utilized for this comparison. The equitoxic concentrations of all four drugs were derived based on their inhibitory activity against human bone marrow samples. For these normalized concentrations, CDDP proved to have a higher cytotoxic activity than its analogues. CBDCA's in vitro activity had a significant correlation with CDDP activity (r = 0.67) in vitro. However, the structurally similar substances MIDP and HIDP demonstrated a much greater degree of association (r = 0.90). Our data suggest that CBDCA, HIDP, and MIDP have overall less activity than CDDP when tested at equitoxic in vit...
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Elsamitrucin (BMY-28090) is an antitumor antibiotic first described in 1985 that has significant oncolytic activity against a number of murine tumors including P388, L1210, B16 and M5076, as well as against MX1 and HCT116 xenografts.... more
Elsamitrucin (BMY-28090) is an antitumor antibiotic first described in 1985 that has significant oncolytic activity against a number of murine tumors including P388, L1210, B16 and M5076, as well as against MX1 and HCT116 xenografts. Preclinical toxicology studies of elsamitrucin revealed edema of multiple organs associated with hypoproteinemia and, at lethal doses, severe multiorgan toxicity. We conducted a phase I clinical trial (31 patients) of elsamitrucin administered as a 10-min i.v. infusion every 3 weeks. The starting dose (0.6 mg/m2) was 1/3 of the dog low toxic dose. The maximum tolerated dose was 30 mg/m2. Dose-limiting toxicity was reversible hepatic dysfunction manifested by elevated transaminase levels not associated with bilirubin, alkaline phosphatase, or lactate dehydrogenase elevations. Other toxicities included nausea, vomiting, malaise, and phlebitis. Because the hepatic toxicity was brief and reversible, a subsequent study (18 patients) was conducted with elsami...
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Three bleomycin(BLM)-resistant sublines were isolated from a human head and neck squamous cell carcinoma cell line (A-253); these sublines (C-IO, D-10, and (.-II) were 4-, 9-, and 21-fold resistant to HIM A,, respectively. These sublines... more
Three bleomycin(BLM)-resistant sublines were isolated from a human head and neck squamous cell carcinoma cell line (A-253); these sublines (C-IO, D-10, and (.-II) were 4-, 9-, and 21-fold resistant to HIM A,, respectively. These sublines were selectively resistant to other members of the BLM class, namely HI,M B2, peplomycin, talisomycin Sim,,and biconi) cinic acid; none of the sublines displayed cross-resistance
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Cancer is a complex disease with many genetic and epigenetic aberrations that result in development of tumorigenic phenotypes. While many factors contribute to the etiology of cancer, emerging data implicate lysophospholipids acting... more
Cancer is a complex disease with many genetic and epigenetic aberrations that result in development of tumorigenic phenotypes. While many factors contribute to the etiology of cancer, emerging data implicate lysophospholipids acting through specific cell-surface, and potentially intracellular, receptors in acquiring the transformed phenotype propagated during disease. Lysophospholipids bind to and activate specific cell-surface G protein-coupled receptors (GPCRs) that initiate cell growth, proliferation, and survival pathways, and show altered expression in cancer cells. In addition, a number of enzymes that increase lysophospholipid production are elevated in particular cell lineages and cancer patients' cells, whereas in a subset of patients, the enzymes degrading lysophospholipids are decreased. Thus, ideal conditions are established to increase lysophospholipids in the tumor microenvironment. Indeed, ascites from ovarian cancer patients, which reflects both the tumor environ...
Research Interests: Genetics, Breast Cancer, Methods, Humans, Female, and 15 moreBlood sampling, Cancer Diagnosis, Enzyme, Growth Factor, Early Diagnosis, Biochemistry and cell biology, Case Control Studies, Lysophosphatidic Acid, Cell Growth, Blood Plasma, False Negative, False Positive, Conditioned media, Breast Neoplasms, and mass Screening
Epidemiologic studies suggest that fish oil, rich in n-3 polyunsaturated fatty acids (PUFA), possesses antitumor activity, whereas n-6 PUFAs may stimulate the development of cancers. The aim of this study was to evaluate the effects of... more
Epidemiologic studies suggest that fish oil, rich in n-3 polyunsaturated fatty acids (PUFA), possesses antitumor activity, whereas n-6 PUFAs may stimulate the development of cancers. The aim of this study was to evaluate the effects of n-6 and n-3 PUFAs on the growth of pancreatic cancer. The n-6 PUFA arachidonic acid (AA) stimulated the growth of cyclooxygenase (COX) 2 positive human pancreatic cancer (PaCa) cells, which was mediated by COX-2 generated prostaglandin E2 (PGE2) binding to EP2 and EP4 receptors. In contrast, the n-3 PUFA eicosapentaenoic acid decreased the growth of COX-2-positive and COX-2-negative PaCa cells. The COX-2-dependent mechanism of eicosapentaenoic acid was mediated by binding of PGE3 to EP2 and EP4 receptors. Dietary intake of n-3 PUFAs decreased the growth of pancreatic cancers in a xenograft model, which was accompanied by a decrease of PGE2 and an increase of PGE3 in the tumors. Our studies provide evidence that n-3 PUFAs possess antitumor activities, ...
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To test the hypothesis that docetaxel may be secreted in tears after intravenous infusion. Prospective pilot trial. Tear fluid was collected from 4 patients receiving docetaxel weekly and 2 patients receiving docetaxel every 3 weeks as a... more
To test the hypothesis that docetaxel may be secreted in tears after intravenous infusion. Prospective pilot trial. Tear fluid was collected from 4 patients receiving docetaxel weekly and 2 patients receiving docetaxel every 3 weeks as a single agent for the treatment of metastatic breast cancer. Tear samples were collected once prior to and again within 30 minutes following the end of the 1-hour docetaxel infusion. A blood sample was also obtained after infusion. The tear and plasma samples were analyzed for drug content using high-performance liquid chromatography and tandem mass spectrometry. Docetaxel was found in the tear samples collected from all 6 patients. The secretion of docetaxel in tears may be a mechanism for canalicular inflammation and tear drainage obstruction, which are known to occur as an adverse effect of the drug.
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Homoharringtonine (HHT), first isolated from the Chinese evergreen Cephalotaxus harringtonia, has been demonstrated to have a broad antitumor activity in rodents and antileukemic effects in humans. We found that HHT was metabolized to an... more
Homoharringtonine (HHT), first isolated from the Chinese evergreen Cephalotaxus harringtonia, has been demonstrated to have a broad antitumor activity in rodents and antileukemic effects in humans. We found that HHT was metabolized to an acid product [HHT-acid; 2'-hydroxy-2'-(alpha-acetic acid)-6'-hydroxy-6'-methylheptanoyl cephalotaxine] when incubated with either human plasma or mouse plasma in vitro. The conversion was faster, however, in mouse plasma, and was both time- and temperature-dependent. Boiled plasma prevented the conversion of HHT to HHT-acid, suggesting that the conversion was enzymatically mediated. When mice were given an intravenous (i.v.) injection of HHT (4 mg/kg), the HHT-acid metabolite was found in both plasma and urine. In mice, HHT-acid was detected in the plasma within 5 min of the i.v. injection of HHT and declined rapidly thereafter. The initial half-lives (t 1/2 alpha) of HHT and HHT-acid were 9 and 17 min, respectively. Twenty-four hour...
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Acute and subchronic toxicities of VRCTC-310, a combination product of crotoxin (CT) and cardiotoxin (CD), which has shown antitumor activity in vivo, have been studied in Beagle dogs. Single i.m. doses of 0.25, 0.5 and 1.0 mg/kg resulted... more
Acute and subchronic toxicities of VRCTC-310, a combination product of crotoxin (CT) and cardiotoxin (CD), which has shown antitumor activity in vivo, have been studied in Beagle dogs. Single i.m. doses of 0.25, 0.5 and 1.0 mg/kg resulted in dose-dependent local muscular toxicity consisting of myofiber atrophy, interstitial edema and macrophage infiltration. Also, AST, ALT and LDH levels increased on day 2, returning to normal values on days 6-8. Local lesions were absent after recovery on day 45. At 2.0 mg/kg, signs of neurotoxicity (ataxia) appeared, in addition to vomitus, salivation, hematuria and myotoxicity in tongue and diaphragm on day 8. Local lesions healed with fibrosis at the site of injection on day 45. Administration of fixed (0.025 and 0.05 mg/kg) or escalating (0.025-0.1 mg/kg) daily doses for 30 days also produced local muscular damage, which was absent at day 75. The increases in AST, ALT and LDH serum activities on days 2-4 were independent of dosing schedule and sharply decreased on day 8, despite continuation of treatment. An escalating dose schedule of 0.025-2.0 mg/kg showed local muscle damage at the site of injection on day 31, however, there were no lesions of myotoxicity in the tongue or diaphragm and no clinical signs of neurotoxicity were observed. Animals tolerated the subchronic treatment better than the acute. The resolution of serum enzymes to normal values during treatment may be attributed to a decrease of sensitivity to VRCTC-310-mediated myotoxic effects.
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Melanoma is the most aggressive form of skin cancer. The rising incidence of melanoma and its poor prognosis in advanced stages are compelling reasons to identify novel therapeutic agents. Though isolated dietary components such as... more
Melanoma is the most aggressive form of skin cancer. The rising incidence of melanoma and its poor prognosis in advanced stages are compelling reasons to identify novel therapeutic agents. Though isolated dietary components such as lycopene, resveratrol, and isothiocyanate compounds have been shown to provide limited protection against cancer development, the use of whole herbs and herbal extracts for the treatment of cancer remains of great interest. As suggested by earlier studies, the antiinflammatory activity of many plants available as intact products or as extracts has long been considered for supplemental therapeutics for cancer. Zyflamend, a unique multiherbal extract preparation, is a promising antiinflammatory agent that has also been suggested to regulate multiple pathways in cancer progression. As Zyflamend contains ingredients that can suppress tumor cell proliferation, invasion, angiogenesis, and metastasis through regulation of inflammatory pathway products, we hypothesized that this preparation might inhibit melanoma proliferation. To test this hypothesis, we studied the effect of Zyflamend on melanoma proliferation. Here, we present that Zyflamend inhibits melanoma growth by regulating the autophagy-apoptosis switch. Based on the responsible molecular mechanisms of Zyflamend, our study highlights the importance of the use of herbal preparations for the prevention and treatment of cancer.
Research Interests: Nutrition and Dietetics, Flow Cytometry, Cell Cycle, Immunohistochemistry, Transmission Electron Microscopy, and 13 moreAutophagy, Apoptosis, Molecular Mechanics, Western blotting, Phytotherapy, Humans, Skin Cancer, Melanoma, Nutrition and Cancer, Plant extracts, Cell Proliferation, Cell Survival, and Antineoplastic Agents
Curcumin, a polyphenolic compound derived from dietary spice turmeric, possesses diverse pharmacologic effects including anti-inflammatory, antioxidant, antiproliferative and antiangiogenic activities. Phase I clinical trials have shown... more
Curcumin, a polyphenolic compound derived from dietary spice turmeric, possesses diverse pharmacologic effects including anti-inflammatory, antioxidant, antiproliferative and antiangiogenic activities. Phase I clinical trials have shown that curcumin is safe even at high doses (12 g/day) in humans but exhibit poor bioavailability. Major reasons contributing to the low plasma and tissue levels of curcumin appear to be due to poor absorption, rapid metabolism, and rapid systemic elimination. To improve the bioavailability of curcumin, numerous approaches have been undertaken. These approaches involve, first, the use of adjuvant like piperine that interferes with glucuronidation; second, the use of liposomal curcumin; third, curcumin nanoparticles; fourth, the use of curcumin phospholipid complex; and fifth, the use of structural analogues of curcumin (e.g., EF-24). The latter has been reported to have a rapid absorption with a peak plasma half-life. Despite the lower bioavailability, therapeutic efficacy of curcumin against various human diseases, including cancer, cardiovascular diseases, diabetes, arthritis, neurological diseases and Crohn&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s disease, has been documented. Enhanced bioavailability of curcumin in the near future is likely to bring this promising natural product to the forefront of therapeutic agents for treatment of human disease.
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Research Interests:
Research Interests: Nutrition and Dietetics, Traditional Medicine, Antioxidants, Phytotherapy, Traditional Chinese Medicine, and 13 moreHumans, Diabetes mellitus, Nitric oxide, Flowers, Gallic acid, Beverages, Seeds, Oral Hypoglycemic Agents, Food Sciences, Medicinal Food, Triterpenes, Clinical Trials as Topic, and Punicaceae
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Two purified animal venom toxins, crotoxin and cardiotoxin, have been combined to produce a unique natural product (VRCTC-310) currently under investigation as an antitumor agent by the National Cancer Institute.In vitro, it has... more
Two purified animal venom toxins, crotoxin and cardiotoxin, have been combined to produce a unique natural product (VRCTC-310) currently under investigation as an antitumor agent by the National Cancer Institute.In vitro, it has demonstrated cytotoxic disease specificity and a unique mechanism of action when submitted to COMPARE analysis.In vivo, tolerance was developed to the neurotoxic properties of crotoxin which allowed
Research Interests:
Research Interests:
Sixteen evaluable patients with metastatic breast cancer were entered into a phase II trial of didemnin B. They received the drug at an initial dose of 5.6 mg/m2 every 21 to 28 days. Major toxicities noted were myalgia and nausea and... more
Sixteen evaluable patients with metastatic breast cancer were entered into a phase II trial of didemnin B. They received the drug at an initial dose of 5.6 mg/m2 every 21 to 28 days. Major toxicities noted were myalgia and nausea and vomiting while myelosuppression was mild. There were no complete responses; however, two minor responses were observed. The pharmacokinetics of didemnin B were studied in 10 patients who received the drug as 30 to 60 min i.v. infusions. A sensitive competitive inhibition enzyme immunoassay was used to quantitate didemnin B levels. Drug was observed to be rapidly cleared from plasma in a biphasic manner (t1/2 alpha = 0.12 hr, t1/2 beta = 4.8 hr). Although the assay could not identify the presence of specific metabolites, the increase of apparent didemnin B levels in plasma at later time points suggested the formation of unidentified metabolites which cross reacted with the antibody in the analytical procedure. In vitro experiments indicated that didemnin B was not bound to bovine serum albumin and only a minor portion (24%) of drug was found associated with red blood cells.
Research Interests: Clinical Trial, Treatment Outcome, Humans, Female, Regression Analysis, and 14 moreCyclic peptides, Aged, Middle Aged, Adult, Metastatic Breast Cancer, Drug evaluation, Red blood cell, Bovine Serum Albumin, Antineoplastic Agents, Phase II Trial, Enzyme Immunoassay, Breast Neoplasms, Neoplasm metastasis, and Pharmacology and pharmaceutical sciences
The synthesis of collagen and non-collagen proteins was studied in rapidly growing male New Zealand rabbits. Animals were divided into sexually immature (i.e. 4 and 8 week old) and mature (i.e. 15 and 26 week old) groups. Comparisons of... more
The synthesis of collagen and non-collagen proteins was studied in rapidly growing male New Zealand rabbits. Animals were divided into sexually immature (i.e. 4 and 8 week old) and mature (i.e. 15 and 26 week old) groups. Comparisons of aorta, lung, and liver protein synthesis and accumulation were made to determine the effect of aging on both collagen and non-collagen proteins. In all tissues there appeared to be an age-related decrease in the relative percent of collagen synthesized. In the lung and liver the relative decrease in percent collagen synthesis resulted from an age-related increase in the synthesis rate of non-collagen proteins. In the aorta the decrease in percent collagen synthesis was primarily a result of a dete of accumulation of tissue proteins correlates more directly with the growth and degree of differentiation of a tissue than with direct animal age.