Plasma Vitamin C Concentrations Were Negatively Associated with Tingling, Prickling or Pins and Needles Sensation in Patients with Postherpetic Neuralgia.

Vitamin C deficiency increases the risk of postherpetic neuralgia (PHN). In this cross-sectional study, the relationships among plasma vitamin C concentrations, pain and Leeds assessment of neuropathic symptoms and signs (LANSS) items were investigated during their first pain clinic visit of 120 PHN patients. The factors associated with vitamin C deficiency were determined. Independent predictors of vitamin C deficiency were presented as adjusted odds ratios (AOR) and 95% confidence intervals (CI). The patients had a high prevalence (52.5%) of vitamin C deficiency. Their plasma vitamin C concentrations were negatively associated with spontaneous pain and tingling, prickling or pins and needles sensation according to the LANSS questionnaire. Based on the receiver operator characteristic curve, the cutoffs for plasma vitamin C to predict moderate-to-severe and severe symptoms of sharp sensation were <7.05 and <5.68 mg/L, respectively. By comparison, the patients well-nourished with vitamin C had lower incidences of sharp sensations, sharp pain, and reddish skin. Multivariate analyses revealed that vitamin C deficiency was associated with the low intake of fruit/vegetables (AOR 2.66, 95% CI 1.09-6.48, p = 0.032), peptic ulcer disease (AOR 3.25, 95% CI 1.28-8.28, p = 0.014), and smoking (AOR 3.60, 95% CI 1.33-9.77, p = 0.010). Future studies are needed to substantiate these findings.

Anti-Metastatic Effects of Antrodan with and without Cisplatin on Lewis Lung Carcinomas in a Mouse Xenograft Model.

Antrodan, a unique protein-bound polysaccharide derived from the fungal mycelia of Antrodia cinnamomea, has been reported to exhibit antitumor and anti-metastatic effects on Lewis lung carcinoma (LLC) cells through direct action and immunomodulation in vitro. In this study, we investigated the combined treatment of antrodan with an anti-cancer drug-cisplatin-and its underlying molecular mechanisms of action in a mouse xenograft tumor model. C57BL/6 mice were implanted (s.c.) with LLCs for nine days, before administration with only antrodan (20 mg/kg and 40 mg/kg; p.o.) daily, only cisplatin (1 mg/kg; i.p.) twice per week, or a combination of both for an additional 28 days. As expected, antrodan on its own significantly inhibited metastasis of lung and liver tissues, while treatment with cisplatin only merely inhibited metastasis of the liver. Antrodan exhibited efficient adjuvant therapy in combination with cisplatin, by inhibiting the activities of the plasma urokinase plasminogen activator (uPA) and the liver matrix metalloproteinase 9 (MMP-9), as well as by inhibiting the phosphorylation of p38 and extracellular signal-regulated kinase 2 (ERK2) in lung and liver tissues. In addition, antrodan effectively ameliorated cisplatin-induced kidney dysfunction when treated combinatorially, as evidenced by a decrease in cisplatin-induced blood urea nitrogen (BUN) levels in plasma and in the level of p38 phosphorylation in the kidney. Mechanistically, the actions of antrodan on its own involved (i) reducing the activities of uPA and MMP-2 and -9 in plasma; (ii) reducing protein expression of MMP-2/9, and the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinases (JNKs), and p38 in lung and liver tissues; and (iii) enhancing immune system functions resulting in the promotion of an anti-metastatic response through immunomodulation, by increasing interferon-γ (IFN-γ) levels and decreasing interleukin-6 (IL-6) levels in plasma. These results demonstrated that antrodan provides a novel, complementary therapeutic strategy against cancer metastasis, by attenuating the activities of MMP-2 and -9 through the modulation of STAT3/MAPK/ERK/JNK signaling pathways, and of the host's immune system.

Multi-Carotenoids at Physiological Levels Inhibit VEGF-Induced Tube Formation of Endothelial Cells and the Possible Mechanisms of Action Both In Vitro and Ex Vivo.

Carotenoids have been shown to exhibit antiangiogenic activities. Several studies have indicated that carotenoids used in combination were more effective on antioxidation and anticancer actions than carotenoids used singly. However, it is unclear whether multi-carotenoids have antiangiogenic effects. We investigated the effects of multi-carotenoids at physiological plasma levels of Taiwanese (abbreviated as MCT, with a total of 1.4 µM) and Americans (abbreviated as MCA, with a total of 1.8 µM), and of post-supplemental plasma levels (abbreviated as HMC with a total of 3.55 µM) on vascular endothelial growth factor (VEGF)-induced tube formation in human umbilical vein endothelial cells (HUVECs) and rat aortic rings. MCT, MCA, and HMC inhibited VEGF-induced migration, invasion, and tube formation of HUVECs as well as new vessels formation in rat aortic rings. MCT, MCA, and HMC inhibited activities o\f matrix metalloproteinase (MMP)-2, urokinase plasminogen activator, and phosphorylation of VEGF receptor 2 induced by VEGF. Moreover, MCT, MCA, and HMC significantly upregulated protein expression of tissue inhibitors of MMP-2 and plasminogen activator inhibitor-1. These results demonstrate the antiangiogenic effect of multi-carotenoids both in vitro and ex vivo with possible mechanistic actions involving attenuation of VEGF receptor 2 phosphorylation and extracellular matrix degradation.

Lycopene Inhibits Metastasis of Human Liver Adenocarcinoma SK-Hep-1 Cells by Downregulation of NADPH Oxidase 4 Protein Expression.

NADPH oxidase 4 (NOX4), with the sole function to produce reactive oxygen species (ROS), can be a molecular target for disrupting cancer metastasis. Several studies have indicated that lycopene exhibited anti-metastatic actions in vitro and in vivo. However, the role of NOX4 in the anti-metastatic action of lycopene remains unknown. Herein, we first confirmed the anti-metastatic effect of lycopene (0.1-5 µM) on human liver adenocarcinoma SK-Hep-1 cells. We showed that lycopene significantly inhibited NOX4 protein expression, with the strongest inhibition of 64.3 ± 10.2% (P < 0.05) at 2.5 µM lycopene. Lycopene also significantly inhibited NOX4 mRNA expression, NOX activity, and intracellular ROS levels in SK-Hep-1 cells. We then determined the effects of lycopene on transforming growth factor ß (TGF-ß)-induced metastasis. We found that TGF-ß (5 ng/mL) significantly increased migration, invasion, and adhesion activity, the intracellular ROS level, matrix metalloproteinase 9 (MMP-9) and MMP-2 activities, the level of NOX4 protein expression, and NOX activity. All these TGF-ß-induced effects were antagonized by the incubation of SK-Hep-1 cells with lycopene (2.5 µM). Using transient transfection of siRNA against NOX4, we found that the downregulation of NOX4 could mimic lycopene by inhibiting cell migration and the activities of MMP-9 and MMP-2 during the incubation with or without TGF-ß on SK-Hep-1 cells. The results demonstrate that the downregulation of NOX4 plays a crucial role in the anti-metastatic action of lycopene in SK-Hep-1 cells.

Black Hoof Medicinal Mushroom Phellinus linteus (Agaricomycetes) Extracts Protect Against Radiation-Induced Hematopoietic Abnormality in Mice.

We investigated the effects of Phellinus linteus extracts (PLEs) against radiation damage in mice. First, BALB/c mice were irradiated once with γ-rays at 4, 5, 6, or 8 Gy and allowed to recover for 20 days. Results reveal that 8-Gy radiation caused death in 100% of mice on day 13, and 6-Gy radiation caused death in 86.7% of mice (13/15) at the end of the experiment, whereas 4- and 5-Gy radiation did not result in any death. We then used 5-Gy γ-ray radiation to examine the protective effects of PLEs. Mice were orally administered a PLE (500, 1000, and 1500 mg/kg) daily for 2 weeks before radiation and for 6 weeks after radiation. γ-Ray radiation significantly decreased body weight starting from week 2 after radiation. Supplementation with a median and high dose of PLE significantly restored body weights starting at weeks 5 and 3, respectively. The radiation-protective agent WR2721 (200 mg/kg intraperitoneally) restored body weights starting at week 4. White blood cells, platelets, red blood cells, and hemoglobin were significantly decreased by radiation, and PLEs (primarily at high doses) and WR2721 significantly prevented hematologic abnormality. These results suggest that PLE has potential as a radioprotective agent.

A Nampt inhibitor FK866 mimics vitamin B3 deficiency by causing senescence of human fibroblastic Hs68 cells via attenuation of NAD(+)-SIRT1 signaling.

Vitamin B3 (niacin) deficiency can cause pellagra with symptoms of dermatitis, diarrhea and dementia. However, it is unclear whether the vitamin B3 deficiency causes human aging. FK866 (a Nampt inhibitor) can reduce intracellular NAD(+) level and induce senescence of human Hs68 cells. However, the mechanisms underlying FK866-induced senescence of Hs68 cells are unclear. In this study, we used FK866 to mimic the effects of vitamin B3 deficiency to reduce the NAD(+) level and investigated the mechanisms of FK866-induced senescence of Hs68 cells. We hypothesized that FK866 induced the senescence of Hs68 cells via an attenuation of NAD(+)-silent information regulator T1 (SIRT1) signaling. We found that FK866 induced cell senescence and diminished cellular NAD(+) levels and SIRT1 activity (detected by acetylation of p53), and these effects were dramatically antagonized by co-treatment with nicotinic acid, nicotinamide, or NAD(+). In contrast, the protein expression of SIRT1, AMP-activated protein kinase, mammalian target of rapamycin, and nicotinamide phosphoribosyltransferase (Nampt) was not affected by FK866. In addition, the role of GSH in the FK866-induced cells senescence may be limited, as N-acetylcysteine did not antagonize FK866-induced cell senescence. These results suggest that FK866 induces cell senescence via attenuation of NAD(+)-SIRT1 signaling. The effects of vitamin B3 deficiency on human aging warrant further investigation.

The anti-angiogenic action of 2-deoxyglucose involves attenuation of VEGFR2 signaling and MMP-2 expression in HUVECs.

AIMS: 2-Deoxyglucose (2-DG) is a glucose analogue and has been shown to inhibit angiogenesis in human umbilical vascular endothelial cells (HUVECs) through interference with N-linked glycosylation. However, the anti-angiogenic mechanisms of 2-DG are not fully elucidated. MAIN METHODS: We first employed an ex vivo rat aortic ring model to substantiate the anti-angiogenic action of 2-DG and then used HUVECs to investigate the molecular mechanism underlying such an action. KEY FINDINGS: Results reveal that 2-DG (0.05-1.0mM) significantly inhibited tube formation in both rat aortic rings and HUVECs. 2-DG (0.1-1.0mM) also significantly inhibited cell invasion and migration, as well as the activity and mRNA and protein expression of matrix metalloproteinase (MMP)-2 in HUVECs. In addition, 2-DG (1.0mM) significantly inhibited mRNA and protein expression of vascular endothelial growth receptor 2 (VEGFR2) in a time-dependent manner. 2-DG also significantly inhibited the phosphorylation of the focal adhesion kinase (FAK) and mitogen-activated protein kinase (p38), the downstream molecules of VEGFR2. The effects of 2-DG on tube formation, MMP-2 activity, and VEGFR2 protein expression in HUVECs were reversed by mannose, an N-linked glycosylation precursor. Mannose also reversed 2-DG-induced accumulation of VEGFR2 in the endoplasmic reticulum. SIGNIFICANCE: This ex vivo and in vitro study demonstrates that 2-DG inhibits angiogenesis with an action involving attenuation of VEGFR2 signaling and MMP-2 expression, possibly resulting from interference with N-linked glycosylation of VEGFR2. Further studies are needed to show that 2-DG inhibits VEGF-mediated angiogenesis or that the actual status of N-glycosylation of VEGFR2 is affected by the treatment.

Multicarotenoids at Physiological Levels Inhibit Metastasis in Human Hepatocarcinoma SK-Hep-1 Cells.

Several studies have demonstrated that single carotenoid, including lycopene, ß-carotene, and α-carotene, exhibits antimetastatic effects; however, little is known whether multicarotenoids have similar effects. Herein, we investigated the antimetastatic effect of multicarotenoids at physiological serum levels in Taiwanese (MCT at 1.4 µM) and American (MCA at 1.8 µM) populations using human hepatocarcinoma SK-Hep-1 cells in comparison with single carotenoid, such as lycopene (0.3 or 0.6 µM, respectively), α-carotene (0.1 µM), ß-carotene (0.4 µM), lutein (0.4 or 0.5 µM, respectively), and ß-cryptoxanthin (0.2 µM). Results reveal that MCA treatment exhibited an additive inhibition on invasion, migration and adhesion at 24 and 48 h of incubation, whereas MCT treatment possessed additive inhibition at 48 h of incubation. The antimetastatic action of MCT and MCA involved additive reduction on activities of matrix metalloproteinase (MMP)-2, -9, and protein expression of Rho and Rac 1 but additive promotion on protein expression of tissue inhibitor of MMP (TIMP)-1 and -2. All of these effects were stronger in MCA than in MCT at 24 and 48 h of incubation. These results demonstrate that multi-carotenoids effectively inhibit metastasis of human hepatocarcinoma SK-Hep-1 cells. More in vivo studies are needed to confirm these findings.

Alpha-carotene inhibits metastasis in Lewis lung carcinoma in vitro, and suppresses lung metastasis and tumor growth in combination with taxol in tumor xenografted C57BL/6 mice.

This study aimed to investigate the anti-metastatic activity of α-carotene (AC) in Lewis lung carcinoma (LLC) and in combination with taxol in LLC-xenografted C57BL/6 mice. Cell culture studies reveal that AC significantly inhibited invasion, migration and activities of matrix metalloproteinase (MMP)-2, -9 and urokinase plasminogen activator but increased protein expression of tissue inhibitor of MMP (TIMP)-1, -2 and plasminogen activator inhibitor (PAI)-1. These effects of AC are similar to those of ß-carotene at the same concentration (2.5 µM). AC (2.5 µM) also significantly inhibited integrin ß1-mediated phosphorylation of focal adhesion kinase (FAK) which then decreased the phosphorylation of MAPK family. Findings from the animal model reveal that AC treatment (5m g/kg) alone significantly decreased lung metastasis without affecting primary tumor growth, whereas taxol treatment (6 mg/kg) alone exhibited significant inhibition on both actions, as compared to tumor control group. AC treatment alone significantly decreased protein expression of integrin ß1 but increased protein expression of TIMP-1 and PAI-1 without affecting protein expression of TIMP-2 and phosphorylation of FAK in lung tissues, whereas taxol treatment alone significantly increased protein expression of TIMP-1, PAI-1 and TIMP-2 but decreased protein expression of integrin ß1 and phosphorylation of FAK. The combined treatment produced stronger actions on lung metastasis and lung tissues protein expression of TIMP-1, TIMP-2 and PAI-1. Overall, we demonstrate that AC effectively inhibits LLC metastasis and suppresses lung metastasis in combination with taxol in LLC-bearing mice, suggesting that AC could be used as an anti-metastatic agent or as an adjuvant for anti-cancer drugs.

Anti-metastatic effects of antrodan, the Antrodia cinnamomea mycelia glycoprotein, in lung carcinoma cells.

This study investigated the anti-metastatic effects of antrodan, the glycoprotein from Antrodia cinnamomea (AC) mycelia, through direct actions and indirect immunomodulatory effects in Lewis lung carcinoma (LLC). Antrodan was isolated from AC mycelia by alkali extraction, acid precipitation, and purification using sepharose CL-6B column chromatography. In the direct anti-metastatic action, antrodan (30-70 µg/mL) was found to significantly inhibit invasion and migration of LLC cells, and these effects involved up-regulation of tissue inhibitor of matrix metalloproteinase (TIMP)-1, TIMP-2, and nm23-H1 protein expression leading to decreased activities and protein expression of MMP-2 and MMP-9. For testing the indirect immunomodulatory effect, antrodan was incubated for 3d with mononuclear cells (MNCs) isolated from human peripheral blood to obtain the condition medium (CM). Antrodan significantly increased interleukin (IL)-12 and IL-1ß levels, but decreased TNF-α, IL-6 and IL-8 levels in the MMC-CM, which also significantly inhibited invasion, migration, and the activities and protein expression of MMP-2 and MMP-9, but significantly increased protein expression of TIMP-1, TIMP-2, and nm23-H1 in LLC cells. The indirect immunomodulatory effect of antrodan was stronger than the direct anti-metastatic effect at the same concentrations (50 and 60 µg/mL). Overall, the results suggest the anti-metastatic potential of antrodan in LLC cells.

Suppression of alpha-tocopherol ether-linked acetic acid in VEGF-induced angiogenesis and the possible mechanisms in human umbilical vein endothelial cells.

Alpha-tocopherol ether-linked acetic acid (α-TEA) has been reported to exhibit both anti-tumor and anti-metastatic activities in cell culture and animal studies. However, it is unclear whether α-TEA possesses anti-angiogenic effects. In this study, we investigated the effect of α-TEA on vascular endothelial growth factor (VEGF)-induced angiogenesis and matrix metalloproteinase (MMP) expression both in vitro and ex vivo. We found that the α-TEA inhibited tube formation, invasion, and migration in human umbilical vein endothelial cells (HUVECs) and that such actions were accompanied by reduced expression of MMP-2. α-TEA also inhibited ex vivo angiogenesis, as indicated by chicken egg chorioallantoic membrane assay. We further showed that α-TEA attenuated protein expression of VEGF receptor-2 (VEGFR-2)-mediated p38 mitogen-activated protein kinase (p38), phosphorylated p38, and focal adhesion kinase (FAK). Moreover, α-TEA (30 µM) significantly up-regulated protein expression of tissue inhibitors of MMP (TIMP)-2 (by 138%) and the metastasis suppressor gene nm23-H1 (by 54%). These results demonstrate that the anti-angiogenic effect of α-TEA both in vitro and ex vivo and its possible mechanistic action appears to involve the inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways and through up-regulation of TIMP-2 and nm23-H1 expression.

Vitamin C protects against cisplatin-induced nephrotoxicity and damage without reducing its effectiveness in C57BL/6 mice xenografted with Lewis lung carcinoma.

Vitamin C (vit C) has been shown to diminish cisplatin (CP)-induced nephrotoxicity and oxidative damage in healthy rats and mice. However, little is known whether vit C has similar actions and enhances the anticancer effect of CP in tumor-bearing mice. Herein, C57BL/6 mice were implanted (s.c.) with Lewis lung carcinoma (LLC) for 9 days before intraperitoneal administration with CP (5 mg/kg) in the presence or absence of low- (200 mg/kg) and high- (1000 mg/kg) dose vit C twice a week for an additional 28 days. Results reveal that vit C or CP treatment alone significantly inhibited tumor growth, although vit C in combination with CP did not further inhibit tumor growth, as compared to CP treatment alone. In addition, CP significantly induced nephrotoxicity and oxidative damage, as evidenced by increased plasma levels of blood urea nitrogen and creatinine as well as levels of lipid peroxidation and carbonyls, decreased ratios of GSH/GSSG in liver and kidney. Vit C significantly reversed these undesirable side effects induced by CP, and most of these actions of vit C were dose-dependent. Overall, we conclude that vit C can protect against CP-induced nephrotoxicity and damage without reducing CP's effectiveness in LLC-bearing mice.

Global assessment of Antrodia cinnamomea-induced microRNA alterations in hepatocarcinoma cells.

Recent studies have demonstrated a potent anticancer potential of medicinal fungus Antrodia cinnamomea, especially against hepatocarcinoma. These studies, however, were performed with prolonged treatments, and the early anticancer events remain missing. To probe the early anticancer mechanisms of A. cinnamomea, we treated SK-Hep-1 liver cancer cell with A. cinnamomea fruiting body extract for 2 and 4 hours, sequenced RNA samples with next-generation sequencing approach, and profiled the genome-wide miRNA and mRNA transcriptomes. Results unmistakably associated the early anticancer effect of A. cinnamomea fruiting body extract with a global downregulation of miRNAs which occurred solely in the A. cinnamomea fruiting body extract-treated SK-Hep-1 cells. Moreover, the inhibitory effect of A. cinnamomea fruiting body extract upon cancer miRNAs imposed no discrimination against any particular miRNA species, with oncomirs miR-21, miR-191 and major oncogenic clusters miR-17-92 and miR-106b-25 among the most severely downregulated. Western blotting further indicated a decrease in Drosha and Dicer proteins which play a key role in miRNA biogenesis, together with an increase of XRN2 known to participate in miRNA degradation pathway. Transcriptome profiling followed by GO and pathway analyses indicated that A. cinnamomea induced apoptosis, which was tightly associated with a downregulation of PI3K/AKT and MAPK pathways. Phosphorylation assay further suggested that JNK and c-Jun were closely involved in the apoptotic process. Taken together, our data indicated that the anticancer effect of A. cinnamomea can take place within a few hours by targeting multiple proteins and the miRNA system. A. cinnamomea indiscriminately induced a global downregulation of miRNAs by simultaneously inhibiting the key enzymes involved in miRNA maturation and activating XRN2 protein involved in miRNA degradation. Collapsing of the miRNA system together with downregulation of cell growth and survival pathways and activation of JNK signaling unleash the extrinsic and intrinsic apoptosis pathways, leading to the cancer cell death.

Antimetastatic effects of α-carotene and possible mechanisms of action in human hepatocarcinoma SK-Hep-1 cells.

In vitro evidence suggests that α-carotene (AC) is an antimetastatic agent against cancer cells, but the mechanistic action is unclear. This study investigated the antimetastatic effect and possible mechanism of AC in comparison with ß-carotene (BC) using human hepatocarcinoma SK-Hep-1 cells. Results reveal that treatment with AC (0.5-2.5 µM) for 48 h significantly inhibited invasion, migration, and adhesion of SK-Hep-1 cells in a concentration-dependent manner. These effects of AC were stronger than those of BC at the same concentration (2.5 µM). Mechanistically, AC significantly decreased activities of urokinase plasminogen activator and matrix metalloproteinases (MMP)-2 and -9, but increased protein expression of plasminogen activator inhibitor-1, tissue inhibitor of MMP (TIMP)-1 and -2, and nm23-H1, an antimetastatic protein. AC also attenuated focal adhesion kinase-mediated phosphorylation of mitogen-activated protein kinase family resulting in decreased protein expression of Rho and Rac 1. Overall, these data suggest that AC has potential as an antimetastatic agent.

Fucoxanthin enhances cisplatin-induced cytotoxicity via NFκB-mediated pathway and downregulates DNA repair gene expression in human hepatoma HepG2 cells.

Cisplain, a platinum-containing anticancer drug, has been shown to enhance DNA repair and to inhibit cell apoptosis, leading to drug resistance. Thus, the combination of anticancer drugs with nutritional factors is a potential strategy for improving the efficacy of cisplatin chemotherapy. In this study, we investigated the anti-proliferative effects of a combination of fucoxanthin, the major non-provitamin A carotenoid found in Undaria Pinnatifida, and cisplatin in human hepatoma HepG2 cells. We found that fucoxanthin (1-10 µΜ) pretreatment for 24 h followed by cisplatin (10 µΜ) for 24 h significantly decreased cell proliferation, as compared with cisplatin treatment alone. Mechanistically, we showed that fucoxanthin attenuated cisplatin-induced NFκB expression and enhanced the NFκB-regulated Bax/Bcl-2 mRNA ratio. Cisplatin alone induced mRNA expression of excision repair cross complementation 1 (ERCC1) and thymidine phosphorylase (TP) through phosphorylation of ERK, p38 and PI3K/AKT pathways. However, fucoxanthin pretreatment significantly attenuated cisplatin-induced ERCC1 and TP mRNA expression, leading to improvement of chemotherapeutic efficacy of cisplatin. The results suggest that a combined treatment with fucoxanthin and cisplatin could lead to a potentially important new therapeutic strategy against human hepatoma cells.

Anti-angiogenic effects of lycopene through immunomodualtion of cytokine secretion in human peripheral blood mononuclear cells.

The carotenoid lycopene has been reported to possess anti-metastatic activity which may be associated with immunomodulation. However, the anti-angiogenic effects and mechanisms of action of lycopene have not been reported. In this study, we investigated the immunomodulatory effect on in vitro and ex vivo angiogenesis of lycopene. We found that the proliferation, migration and the matrigel tube formation of human umbilical vein endothelial cells (HUVECs) was remarkably inhibited by conditioned medium (CM) of human peripheral blood mononuclear cells (MNC-CM) stimulated with various dose (1-10 µmol/L) of lycopene (LP-MNC-CM). LP-MNC-CM treatment inhibited ex vivo angiogenesis, as revealed by chicken egg chorioallantoic membrane assay. We further examined the effects of lycopene stimulation on cytokine levels in MNC and showed that, as compared to the control, lycopene (10 µmol/L) significantly (P<.001) up-regulated interleukin (IL)-12 by 163% and interferon (IFN)-γ by 531%. Furthermore, pre-treatment of HUVECs with dexamethasone, an IL-12 inhibitor, blocked the anti-angiogenic effects of LP-MNC-CM in parallel with inhibition of IL-12 and IFN-γ induction in MNC. These results demonstrate that lycopene has a potent anti-angiogenic effect and that these effect may be associated with its up-regulation of IL-12 and IFN-γ.

Lycopene inhibits angiogenesis both in vitro and in vivo by inhibiting MMP-2/uPA system through VEGFR2-mediated PI3K-Akt and ERK/p38 signaling pathways.

SCOPE: Limited in vitro data show that lycopene may be anti-angiogenic but with unclear mechanisms. Here, we employed ex vivo and in vivo assays to substantiate the anti-angiogenic action of lycopene and determined its molecular mechanisms in human umbilical vein endothelial cells (HUVECs). METHODS AND RESULTS: The anti-angiogenic activity of lycopene was confirmed by ex vivo rat aortic ring and in vivo chorioallantoic membrane assays. Furthermore, the in vivo matrigel plug assay in mice demonstrated that lycopene implanted s.c. at the highest dose used (400 µg/plug) completely inhibited the formation of vascular endothelial cells induced by vascular endothelial growth factor (VEGF). As expected, lycopene inhibited tube formation, invasion, and migration in HUVECs, and such actions were accompanied by reduced activities of matrix metalloproteinase-2, urokinase-type plasminogen activator, and protein expression of Rac1, and by enhancing protein expression of tissue inhibitors of metalloproteinase-2 and plasminogen activator inhibitor-1. Moreover, lycopene attenuated VEGF receptor-2 (VEGFR2)-mediated phosphorylation of extracellular signal-regulated kinase (ERK), p38, and Akt as well as protein expression of PI3K. CONCLUSION: Our data demonstrate the anti-angiogenic effect of lycopene both in vitro and in vivo. The anti-angiogenic activity of lycopene may involve inhibition of MMP-2/uPA system through VEGFR2-mediated PI3K-Akt and ERK/p38 signaling pathways.

Diverse effects of ß-carotene on secretion and expression of VEGF in human hepatocarcinoma and prostate tumor cells.

Oral administration of ß-carotene (BC) was found to exert opposite effects on plasma levels of vascular endothelial growth factor (VEGF) in two animal models. One study in nude mice injected via tail vein with hepatocarcinoma SK-Hep-1 cells showed that BC decreases the plasma VEGF level, whereas the other study in nude mice injected subcutaneously with prostate tumor PC-3 cells showed that BC increases the plasma VEGF level. Herein we investigated whether BC (0.5-20 µM) possesses diverse effects on VEGF secretion in SK-Hep-1, PC-3 and melanoma B16F10 cells. We found that incubation of SK-Hep-1 cells with BC (1-20 µM) for 6 h significantly decreased VEGF secretion, whereas BC (1-10 µM) significantly increased the VEGF secretion in PC-3 cells. However, these effects disappeared at 12 h of incubation. Similar effects occurred in VEGF mRNA and protein expression after treatment of SK-Hep-1 and PC-3 cells with BC for 6 h. In contrast, BC (0.5-20 µM) did not affect mRNA and protein expression and secretion of VEGF in B16F10 cells. We also found that the proliferation of SK-Hep-1 and B16F10 cells was significantly inhibited by 20 µM BC at 6 and 12 h of incubation, whereas the proliferation of PC-3 cells was significantly inhibited by 20 µM BC at 12 h of incubation. In summary, the present study demonstrated the tumor-specific effect of BC on VEGF secretion in different cancer cell lines.

Fucoxanthin attenuates rifampin-induced cytochrome P450 3A4 (CYP3A4) and multiple drug resistance 1 (MDR1) gene expression through pregnane X receptor (PXR)-mediated pathways in human hepatoma HepG2 and colon adenocarcinoma LS174T cells.

Pregnane X receptor (PXR) has been reported to regulate the expression of drug-metabolizing enzymes, such as the cytochrome P450 3A (CYP3A) family and transporters, such as multiple drug resistance 1 (MDR1). Fucoxanthin, the major carotenoid in brown sea algae, is a putative chemopreventive agent. In this study, we determined whether fucoxanthin could overcome drug resistance through attenuation of rifampin-induced CYP3A4 and MDR1 gene expression by PXR-mediated pathways in HepG2 hepatoma cells. We found that fucoxanthin (1-10 µM) significantly attenuated rifampin (20 µM)-induced CYP3A4, MDR1 mRNA and CYP3A4 protein expression at 24 h of incubation. Mechanistically, fucoxanthin strongly attenuated the PXR-mediated CYP3A4 promoter activity in HepG2 cells. In addition, fucoxanthin attenuated constitutive androstane receptor (CAR)- and rPXR-mediated CYP3A4 promoter activity in this cell line. Using the mammalian two-hybrid assay, we found that fucoxanthin significantly decreased the interaction between PXR and SRC-1, a PXR co-activator. Thus, fucoxanthin can decrease rifampin-induced CYP3A4 and MDR1 expression through attenuation of PXR-mediated CYP3A4 promoter activation and interaction between PXR and co-activator. These findings could lead to potentially important new therapeutic and dietary approaches to reduce the frequency of adverse drug reactions.

Antimetastatic effects and mechanisms of apo-8'-lycopenal, an enzymatic metabolite of lycopene, against human hepatocarcinoma SK-Hep-1 cells.

Lycopene is primarily metabolized by carotenoid monoxygenase II into apo-8'- and apo-12'-lycopenal in the rat liver. Although lycopene possesses antimetastatic activity in a highly invasive hepatoma SK-Hep-1 cell line, little is known whether its metabolites have a similar effect. In this study, we investigated the antimetastatic effects of apo-8'-lycopenal (1-10 µM) in comparison with lycopene (10 µM) in SK-Hep-1 cells. We found that both apo-8'-lycopenal and lycopene inhibited the invasion and migration of SK-Hep-1 cells, and the effect of apo-8'-lycopenal was stronger than that of lycopene at the same concentration (10 µM). Mechanistically, apo-8'-lycopenal: 1) decreased the activities and protein expression of metalloproteinase-2 (MMP-2) and -9; 2) increased the protein expression of nm23-H1 and the tissue inhibitor of MMP (TIMP)-1 and -2; 3) suppressed protein expression of Rho small GTPases; and 4) inhibited focal adhesion kinase-mediated signaling pathway, such as ERK/p38 and PI3K-Akt axis. Overall, these results demonstrate that apo-8'-lycopenal possesses antimetastatic activity in SK-Hep-1 cells and that this effect is stronger than that of lycopene, suggesting that the antimetastatic effect may be attributed, at least in part, to its metabolites such as apo-8'-lycopenal.