Phosphoinositol 3-kinase, a novel target molecule for the inhibitory effects of juglone on TPA-induced cell transformation (original) (raw)
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Journal of Food Bioactives, 2018
Hypoxia-inducible factor -1 alpha (HIF-1α), vascular endothelial growth factor (VEGF), and phosphorylated Akt (p-Akt) are critical in pancreatic cancer cell growth, angiogenesis and metastasis. The ability of MIA Paca-2 pancreatic cancer cells to migrate and invade after treatment with juglone (5 hydroxy-1, 4-naphthoquinone) was analyzed by a transwell invasion and migration assay, a wound healing assay, and an in vitro tube formation assay using human umbilical vein endothelial cells (HUVEC). ELISA was used to determine the levels of HIF1-α. Western blot analysis was used to determine the level of VEGF, p-Akt, and carbonic anhydrase IX expression. Juglone down-regulated the expression of HIF-1α, VEGF, and significantly suppressed the phosphorylation of Akt. Juglone dose-dependently inhibited the metastatic potential of pancreatic cancer cells by inhibiting cell migration, invasion and wound healing assays. Juglone attenuated the aggressiveness of pancreatic cancer cells in vitro.
Cell Biology International, 2009
This study demonstrates cytotoxic and genotoxic potential of juglone, a chief constituent of walnut, and its underlying mechanisms against melanoma cells. MTT assay and clonogenic assay were used to study cytotoxicity, micronucleus assay to assess genotoxicity, glutathione (GSH) assay and 2 0 ,7 0 -dicholorofluorescein diacetate (DCFH-DA) assay to evaluate the oxidative stress induction. Apoptosis/necrosis induction was analysed by flow cytometry. We observed a concentration-dependent decrease in cell survival with a corresponding increase in the lactate dehydrogenase levels. A dose-dependent increase in the frequency of micronucleated binucleate cells indicated the potential of juglone to induce cytogenetic damage in melanoma tumor cells. Moreover, results of the micronuclei study indicated division delay in the proliferating cell population by showing decrease in the cytokinesis blocked proliferation index. Further, juglone-induced apoptosis and necrosis could be demonstrated by oligonucleosomal ladder formation, microscopic analysis, increase in the hypodiploid fraction (sub Go peak in DNA histogram), as well as an increased percentage of AnnexinV(þ)/PI(þ) cells detected by flow cytometry. A significant concentration-dependent decrease in the glutathione levels and increase in dichlorofluorescein (DCF) fluorescence after juglone treatment confirmed the ability of juglone to generate intracellular reactive oxygen species. The cytotoxic effect of juglone can be attributed to mechanisms including the induction of oxidative stress, cell membrane damage, and a clastogenic action leading to cell death by both apoptosis and necrosis. Ó
Juglone: A therapeutic phytochemical from Juglans regia L
Journal of Medicinal Plants Research, 2011
Juglans regia L. is a monoecious, heterodichogamous, deciduous tree species valued for its highquality timber as well as its nuts. It belongs to the family Juglandaceae. Though, it is native to Central Asia, India, Nepal China and some part of Europe, it is being grown commercially in the USA, France, Italy and Spain for nut production. The nuts and plant parts of J. regia contain the aromatic secondary metabolite juglone (C 10 H 6 O 3) (1, 4-naptha quinone, 5 hydroxy-8CI). Juglone is a well-known allelopathic agent and being used in commercial hair dye and also has therapeutic properties. Juglone is commercially extracted from the husks of walnuts, but fresh leaves of J. regia contain significant amounts of juglone (up to 0.5 / 100 g dry weight) to be a good source of the chemical. Juglone is understudy for anti-carcinogenic effects. In human intestinal neoplasia juglone checked multiplicity of tumour cells and is also a strong inhibitor of peptidyl-prolyl isomerase Pin1 which is overexpressed in several types of cancer affected cells. Juglone increases efficacy of anti cancer drugs as well.
Antiproliferative activity of Juglone derivatives on rat glioma
Natural Product Research, 2016
Malignant gliomas are aggressive and life-threatening tumours that still show a poor prognosis: the current therapeutic approach based on surgical resection and chemotherapy combined with radiotherapy does not provide a satisfactory chance of long-term survival to patients. Natural bioactive compounds represent a precious source of molecules with antiproliferative activity, potentially effective also against glioma cells. Among these, juglone is a known allelopathic compound extracted from the eastern black walnut (Juglans nigra) which anti-mitotic effect has been extensively described in mammalian cells. We investigated the antiproliferative effect of a synthetic derivative of this natural compound, 2-(2,4-dihydroxyphenyl)-8-hydroxy-1,4naphthoquinone (DiNAF), in rat glioma cells. We compared this molecule and its effect with the natural reference compound and with newly synthesized derivatives to build a preliminar structureactivity relationship. Biological assays and NMR-based redox experiments confirmed that DiNAF is a promising lead and supported the hypothesis of a redox mechanism underlying its cytotoxic activity.
Effects of Juglone on Antioxidant Status in Pancreatic Cancer Cell Lines
Journal of Medical Sciences and Health
Background: Naphthoquinones have protective effects through different mechanism against to human malignancies including pancreatic cancer. One of these mechanisms is to avoid reactive oxygen species (ROS) production. Changes in enzymatic (superoxide dismutases, catalase [CAT], ascorbate peroxidase, glutathione peroxidase, and glutathione reductase) antioxidant systems, such as formation of an oxidative biomarker (H 2 O 2 , malondialdehyde, ischemic modified albümin, etc.) have a critical role in ROS mechanism. According to this knowledge, we evaluated the anticancer and antioxidant activity of the juglone. Objectives: The aim of this study was to investigate the cytotoxic activity of juglone and to investigate its effect on antioxidant activity in BxPC-3 and PANC-1 pancreatic cancer cell lines. Materials and Methods: The cytotoxic activities of juglone on cell viability were investigated on pancreatic cancer cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell viability test. One of the antioxidant enzymes, CAT activities and antioxidant status marker reduced glutathione (GSH) levels were measured by spectrophotometric analysis. We compared the groups as juglone treatment and control groups (no treatment) at different hours (24 th , 48 th and 72 th h). Results: Juglone reduced the cell viability of human pancreatic cancer cells in a concentration-dependent manner. Juglone supplementation showed an antiproliferative effect toward pancreatic cancer cell lines at IC 50 values. The IC 50 of juglone on BxPC-3 and PANC-1 pancreatic cell line was 21.05 μM and 21.25 μM, respectively. Furthermore, juglone had a significantly higher degree of enzymatic activity to compensate the oxidative stress. CAT activity was found a significant increase compared to the control group at 24, 48, and 72 h in PANC-1 cells; it was found a significant increase at 72 h in BxPC-3 cell line. Reduced glutathione level is decreased at 24 and 48 h while at 72 h GSH level is increased in BxPC-3 cell line after juglone treatment compared to the control group. In PANC-1 cell line, GSH level is increased at 24 and 48 h, but it was decreased at 72 h compared to the control group. Conclusion: Our results indicate that juglone can be a potent anticancer molecule and may prove essential in pancreatic cancer therapy. Juglone may play a central role in antioxidant system defense in pancreatic cells.
Journal of Cellular Biochemistry, 2004
We have earlier shown that oral infusion of a polyphenolic fraction isolated from green tea, at a human achievable dose (equivalent to six cups of green tea per day), significantly inhibits prostate cancer (PCA) development and metastasis in transgenic adenocarcinoma of mouse prostate (TRAMP) model that closely mimics progressive form of human prostatic disease : Proc. Natl. Acad. Sci. U.S.A. 98:10350-10355.). A complete understanding of the mechanism(s) and molecular targets of PCA chemopreventive effects of tea polyphenols may be useful in developing novel approaches for its prevention. In this study, we employed two distinct human PCA cell lines viz. DU145 (androgenunresponsive prostate carcinoma cells) and LNCaP (androgen-responsive prostate carcinoma cells) and, employing immunoblot analysis, we evaluated the effect of epigallocatechin-3-gallate (EGCG), the major polyphenol present in green tea and theaflavins (TF), the major polyphenol present in black tea on phosphatidylinositol-3-kinase (PI3K)/protein kinase B (PKB) and mitogen-activated protein kinase (MAPK) pathways. Both EGCG and TF treatment were found to (i) decrease the levels of PI3K and phospho-Akt and (ii) increase Erk1/2 in both DU145 and LNCaP cells. Our data showing the inhibition of the constitutive levels of PI3K and the phosphorylation of Akt could be important because the treatment approaches should be aimed at the inhibition of the constitutive levels of PI3K and Akt. Our data also suggest that Erk1/2 could be involved in the anti-cancer effects of EGCG and TF. Taken together, our study, for the first time demonstrated the modulation of the constitutive activation of PI3K/Akt and Erk1/2 pathways by EGCG as well as TF. We suggest that detailed studies in appropriate tumor model system are needed to establish the relevance of the cell culture work to in vivo models.
Free Radical Biology and Medicine, 2012
Polymeric black tea polyphenols (PBPs) have been shown to possess anti-tumor-promoting effects in two-stage skin carcinogenesis. However, their mechanisms of action are not fully elucidated. In this study, mechanisms of PBP-mediated antipromoting effects were investigated in a mouse model employing the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Compared to controls, a single topical application of TPA to mouse skin increased the translocation of protein kinase C (PKC) from cytosol to membrane. Pretreatment with PBPs 1-3 decreased TPA-induced translocation of PKC isozymes (a, b, Z, g, e) from cytosol to membrane, whereas PBPs 4 and 5 were less effective. The levels of PKCs d and z in cytosol/membrane were similar in all the treatment groups. Complementary confocal microscopic evaluation showed a decrease in TPA-induced PKCa fluorescence in PBP-3-pretreated membranes, whereas pretreatment with PBP-5 did not show a similar decrease. Based on the experiments with specific enzyme inhibitors and phosphospecific antibodies, both PBP-3 and PBP-5 were observed to decrease TPA-induced level and/or activity of phosphatidylinositol 3-kinase (PI3K) and AKT1 (pS473). An additional ability of PBP-3 to inhibit site-specific phosphorylation of PKCa at all three positions responsible for its activation [PKCa (pT497), PKC PAN (bII pS660), PKCa/bII (pT638/ 641)] and AKT1 at the Thr308 position, along with a decrease in TPA-induced PDK1 protein level, correlated with the inhibition of translocation of PKC, which may impart relatively stronger chemoprotective activity to PBP-3 than to PBP-5. Altogether, PBP-mediated decrease in TPA-induced PKC phosphorylation correlated well with decreased TPA-induced NF-kB phosphorylation and downstream target proteins associated with proliferation, apoptosis, and inflammation in mouse skin. Results suggest that the antipromoting effects of PBPs are due to modulation of TPA-induced PI3Kmediated signal transduction.
Tumor Growth Inhibitory Effect of Juglone and Its Radiation Sensitizing Potential
Integrative Cancer Therapies, 2011
The present study aimed at evaluating the anticancer and radiosensitizing potential of juglone against a chemoresistant and radioresistant tumor (B16F1 melanoma) growing on C57BL/6J mice. Volume doubling time, growth delay, and median survival were used to assess the in vivo anticancer and radiosensitizing potential of juglone. In vitro radiosensitizing potential of juglone was studied using clonogenic, comet, and reactive oxygen species induction assays. Treatment of tumor-bearing mice with sublethal doses of juglone caused a dose-dependent inhibition of tumor growth as evident from the growth delay and median survival values. Comet assay using tumor tissue and blood showed differential toxicity of juglone, where higher levels of DNA damage was seen in tumor tissue compared with blood cells. Pretreatment of tumor-bearing mice with optimum dose of juglone before radiation resulted in significant tumor growth inhibition compared with radiation alone. From the clonogenic assay, the au...
Integrative cancer therapies, 2012
The present study aimed at evaluating the anticancer and radiosensitizing potential of juglone against a chemoresistant and radioresistant tumor (B16F1 melanoma) growing on C57BL/6J mice. Volume doubling time, growth delay, and median survival were used to assess the in vivo anticancer and radiosensitizing potential of juglone. In vitro radiosensitizing potential of juglone was studied using clonogenic, comet, and reactive oxygen species induction assays. Treatment of tumor-bearing mice with sublethal doses of juglone caused a dose-dependent inhibition of tumor growth as evident from the growth delay and median survival values. Comet assay using tumor tissue and blood showed differential toxicity of juglone, where higher levels of DNA damage was seen in tumor tissue compared with blood cells. Pretreatment of tumor-bearing mice with optimum dose of juglone before radiation resulted in significant tumor growth inhibition compared with radiation alone. From the clonogenic assay, the authors observed a sensitization enhancement ratio of 1.37 for the combination treatment compared with radiation alone. Furthermore, comet assay studies revealed the potential of juglone to enhance the radiation-induced DNA damage and cause a delay in its repair. Juglone pretreatment before radiation also resulted in a significant elevation in the intracellular reactive oxygen species levels compared with radiation alone. In conclusion, the results of this study show the potential of juglone to inhibit the growth of melanoma in vivo. The study also revealed the potential of juglone to augment the radiation-induced cell death of melanoma cells, which may be attributed to oxidative stress-mediated DNA damage and its delayed repair.