Effect of 2,5-dimethylphenol on Ca(2+) movement and viability in PC3 human prostate cancer cells.

The phenolic compound 2,5-dimethylphenol is a natural product. 2,5-Dimethylphenol has been shown to affect rat hepatic and pulmonary microsomal metabolism. However, the effect of 2,5-dimethylphenol on Ca(2+ )signaling and cyotoxicity has never been explored in any culture cells. This study explored the effect of 2,5-dimethylphenol on cytosolic free Ca(2+ )levels ([Ca(2+)]i) and cell viability in PC3 human prostate cancer cells. 2,5-Dimethylphenol at concentrations between 500 µM and 1000 µM evoked [Ca(2+)]i rises in a concentration-dependent manner. This Ca(2+ )signal was inhibited by approximately half by the removal of extracellular Ca(2+). 2,5-Dimethylphenol-induced Ca(2+ )influx was confirmed by Mn(2+)-induced quench of fura-2 fluorescence. Pretreatment with the protein kinase C (PKC) inhibitor GF109203X, nifedipine or the store-operated Ca(2+ )entry inhibitors (econazole or SKF96365) inhibited 2,5-dimethylphenol-induced Ca(2+ )signal in Ca(2+)-containing medium by ∼30%. Treatment with the endoplasmic reticulum Ca(2+ )pump inhibitor thapsigargin in Ca(2+)-free medium abolished 2,5-dimethylphenol-induced [Ca(2+)]i rises. Conversely, treatment with 2,5-dimethylphenol abolished thapsigargin-induced [Ca(2+)]i rises. Inhibition of phospholipase C (PLC) with U73122 reduced 2,5-dimethylphenol-evoked [Ca(2+)]i rises by ∼80%. 2,5-Dimethylphenol killed cells at concentrations of 350-1000 µM in a concentration-dependent fashion. Chelation of cytosolic Ca(2+ )with 1,2-bis(2-aminophenoxy)ethane-N, N, N', N'-tetraacetic acid/AM (BAPTA/AM) did not prevent 2,5-dimethylphenol's cytotoxicity. Together, in PC3 cells, 2,5-dimethylphenol induced [Ca(2+)]i rises that involved Ca(2+ )entry through PKC-regulated store-operated Ca(2+ )channels and PLC-dependent Ca(2+ )release from the endoplasmic reticulum. 2,5-Dimethylphenol induced cytotoxicity in a Ca(2+)-independent manner.

Isolation and cytotoxicity evaluation of the chemical constituents from Cephalantheropsis gracilis.

Cephalantheropsis gracilis afforded five new compounds: cephalanthrin-A (1), cephalanthrin-B (2), cephathrene-A (3), cephathrene-B (4), methyl 2-(aminocarbonyl) phenylcarbamate (5), and 52 known compounds. The structures of the new compounds were determined by spectroscopic analysis. Among the compounds isolated, tryptanthrin (6), phaitanthrin A (7), cephalinone D (19), and flavanthrin (30) showed significant cytotoxicity against MCF-7, NCI-H460, and SF-268 cell lines.

Antioxidant and Anti-Inflammatory Properties of Longan (Dimocarpus longan Lour.) Pericarp.

This study examined the antioxidant and anti-inflammatory activities of the water extract of longan pericarp (WLP). The results showed that WLP exhibited radical scavenging, reducing activity and liposome protection activity. In addition, WLP also inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophages. Further, administration of WLP, in the range of 100-400 mg/kg, showed a concentration-dependent inhibition on paw edema development following carrageenan (Carr) treatment in mice. The anti-inflammatory effects of WLP may be related to NO and tumor necrosis factor (TNF-α) suppression and associated with the increase in the activities of antioxidant enzymes, including catalase, superoxide dismutase, and glutathione peroxidase. Overall, the results showed that WLP might serve as a natural antioxidant and inflammatory inhibitor.

Antioxidant, Antinociceptive, and Anti-Inflammatory Activities from Actinidia callosa var. callosa In Vitro and In Vivo.

Actinidia callosa var. callosa has been widely used to treat antipyretic, analgesic, anti-inflammation, abdominal pain, and fever in Taiwan. The aim of this study was to evaluate the antioxidant, antinociceptive, and anti-inflammatory lipopolysaccharide-(LPS-)induced nitric oxide (NO) production in RAW264.7 macrophages and pawedema induced by λ-carrageenan activities of the methanol extract from A. callosa. In HPLC analysis, the fingerprint chromatogram of ethyl-acetate fraction of A. callosa (EAAC) was established. EAAC showed the highest TEAC and DPPH radical scavenging activities, respectively. We evaluated that EAAC and the reference compound of catechin and caffeic acid decreased the LPS-induced NO production in RAW264.7 cells. Treatment of male ICR mice with EAAC significantly inhibited the numbers of acetic acid-induced writhing response and the formalin-induced pain in the late phase. Administration of EAAC showed a concentration-dependent inhibition on paw edema development after Carr treatment in mice. Anti-inflammatory mechanisms of EAAC might be correlated to the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and heme oxygenase-1 (HO-1) in vitro and in vivo. Overall, the results showed that EAAC demonstrated antioxidant, antinociceptive, and anti-inflammatory activity, which supports previous claims of the traditional use for inflammation and pain.

Ameliorative Effects of Scopoletin from Crossostephium chinensis against Inflammation Pain and Its Mechanisms in Mice.

Scopoletin exists in nature as an anti-oxidant, hepatoprotective, and anti-inflammatory activities reagent. In this study, we have investigated the analgesic effects of the scopoletin using the models of acetic acid-induced writhing response and the formalin test, the anti-inflammatory effects of scopoletin using model of λ-carrageenan (Carr)-induced paw edema. The treatment of ICR mice with scopoletin inhibited the numbers of writhing response and the formalin-induced pain in the late phase. This study demonstrated that the administration of scopoletin resulted in the reduction of Carr-induced mice edema, and it increased the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) after Carr injection. We also demonstrated scopoletin significantly attenuated the malondialdehyde (MDA) level in the edema paw after Carr injection. Scopoletin decreased the NO, tumor necrosis factor (TNF-α) and prostaglandin E2 (PGE(2)) levels on serum after Carr injection. Scopoletin decreased Carr-induced inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions in the edema paw. These anti-inflammatory mechanisms of scopoletin might be related to the decrease in the level of MDA via increasing the activities of SOD, CAT, and GPx in the edema paw. Also, scopoletin could affect the production of NO, TNF-α, and PGE(2), and therefore affect the anti-inflammatory effects.

Synergistic inhibitory effects of cetuximab and curcumin on human cisplatin-resistant oral cancer CAR cells through intrinsic apoptotic process.

Cetuximab, an epidermal growth factor receptor (EGFR)-targeting monoclonal antibody (mAb), is a novel targeted therapy for the treatment of patients with oral cancer. Cetuximab can be used in combination with chemotherapeutic agents to prolong the overall survival rates of patients with oral cancer. Curcumin is a traditional Chinese medicine, and it has been demonstrated to have growth-inhibiting effects on oral cancer cells. However, information regarding the combination of cetuximab and curcumin in drug-resistant oral cancer cells is lacking, and its underlying mechanism remains unclear. The purpose of the present study was to explore the oral anticancer effects of cetuximab combined with curcumin on cisplatin-resistant oral cancer CAR cell apoptosis in vitro. The results demonstrated that combination treatment synergistically potentiated the effect of cetuximab and curcumin on the suppression of cell viability and induction of apoptosis in CAR cells. Cetuximab and curcumin combination induced apoptosis and dramatically increased caspase-3 and caspase-9 activities compared with singular treatment. Combination treatment also markedly suppressed the protein expression levels of EGFR and mitogen-activated protein kinases (MAPKs) signaling (phosphorylation of ERK, JNK and p38). The results demonstrated that co-treatment with cetuximab and curcumin exerts synergistic oral anticancer effects on CAR cells through the suppression of the EGFR signaling by regulation of the MAPK pathway.

ITR­284 modulates cell differentiation in human chronic myelogenous leukemia K562 cells.

ITR­284 is a carboxamide analog that can inhibit proliferation in human promyelocytic leukemia HL-60 cells. To understand the effects and molecular mechanisms of ITR­284 in human erythromyeloblastoid leukemia, we treated K562 cells with different concentrations of ITR­284 (0, 2, 4, 6, 8 and 10 nM) and all-trans retinoic acid (ATRA) (0, 0.1, 0.5, 1, 5 and 10 µM) for 24 h. The IC50 of ITR­284 was ~10 nM in K562 cells treated for 24 h as determined by MTT assay. May-Grünwald-Giemsa staining and nitro blue tetrazolium (NBT) assays were used to determine cell morphology changes and differentiation after ITR­284 and ATRA treatment. In addition, mRNA expression levels of hematopoietic factors, including GATA­1, NF-E2 and GATA­2, were elevated, while expression levels of BCR­ABL were downregulated in K562 cells after 24 h of treatment with ITR­284 as determined by quantitative reverse transcription polymerase chain reaction. In addition, western blot analyses showed that FOXM1, GLI 1 and c-MYC protein levels were decreased by ITR­284. Taken together, our data show that ITR­284 induced K562 cell differentiation, which led to decreased tumorigenesis. Our findings suggest that ITR­284 could be a potential candidate for treating chronic myelogenous leukemia.

Resveratrol-induced autophagy and apoptosis in cisplatin-resistant human oral cancer CAR cells: A key role of AMPK and Akt/mTOR signaling.

Resveratrol is known to be an effective chemo-preventive phytochemical against multiple tumor cells. However, the increasing drug resistance avoids the cancer treatment in oral cavity cancer. In this study, we investigated the oral antitumor activity of resveratrol and its mechanism in cisplatin-resistant human oral cancer CAR cells. Our results demonstrated that resveratrol had an extremely low toxicity in normal oral cells and provoked autophagic cell death to form acidic vesicular organelles (AVOs) and autophagic vacuoles in CAR cells by acridine orange (AO) and monodansylcadaverine (MDC) staining. Either DNA fragmentation or DNA condensation occurred in resveratrol-triggered CAR cell apoptosis. These inhibitors of PI3K class III (3-MA) and AMP-activated protein kinase (AMPK) (compound c) suppressed the autophagic vesicle formation, LC3-II protein levels and autophagy induced by resveratrol. The pan-caspase inhibitor Z-VAD-FMK attenuated resveratrol-triggered cleaved caspase-9, cleaved caspase-3 and cell apoptosis. Resveratrol also enhanced phosphorylation of AMPK and regulated autophagy- and pro-apoptosis-related signals in resveratrol-treated CAR cells. Importantly, resveratrol also stimulated the autophagic mRNA gene expression, including Atg5, Atg12, Beclin-1 and LC3-II in CAR cells. Overall, our findings indicate that resveratrol is likely to induce autophagic and apoptotic death in drug-resistant oral cancer cells and might become a new approach for oral cancer treatment in the near future.

Hepatoprotective effect of Phyllanthus in Taiwan on acute liver damage induced by carbon tetrachloride.

The effect of oral administration of Phyllanthus methanolic extracts (PME) (i.e. P. acidus, P. emblica, P. myrtifolius, P. multiflorus, P. amarus, P. debilis, P. embergeri, P. hookeri, P. tenellus, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria) or gallic acid (GA) on the progression of acute liver damage induced by CCl(4) in rats was examined by morphological and biochemical methods. P. acidus, P. urinaria L.s. urinaria, GA at a dose of 0.5 g/kg, and P. emblica, P. urinaria L.s. nudicarpus at a dose of 1.0 g/kg attenuated CCl(4)-induced increase in serum glutamate-oxalate-transaminase (GOT). P. acidus, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria, GA at a dose of 0.5 g/kg, and P. emblica, P. amarus, P. hookeri, P. tenellus at a dose of 1.0 g/kg attenuated CCl(4)-induced increase in serum glutamate-pyruvate-transaminase (GPT). Concurrently, P. acidus, P. multiflorus, P. embergeri, P. hookeri, P. tenellus and P. urinaria L.s. urinaria elevated the activity of liver reduced glutathione peroxidase (GSH-Px). Since the protective effects of P. acidus, P. emblica, P. myrtifolius, P. embergeri, P. urinaria L.s. nudicarpus, P. urinaria L.s. urinaria and GA correlate with a reduction in liver infiltration and focal necrosis observed using histological methods, these data demonstrate that P. acidus and P. urinaria L.s. urinaria are hepatoprotective and antioxidant agents.

Anti-inflammatory effects of trilinolein from Panax notoginseng through the suppression of NF-κB and MAPK expression and proinflammatory cytokine expression.

In this study, we have investigated the anti-inflammatory effects of trilinolein (TL) using a lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) and carrageenan (Carr)-induced mouse paw edema model. When RAW264.7 macrophages were treated with different concentrations of TL together with LPS, a significant concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), interleukin-1 (IL-1ß), and IL-6 production was detected. Western blotting revealed that TL blocked the protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor-κB (NF-κB), IκBα, and mitogen-activated protein kinases (MAPKs). In the anti-inflammatory test, TL decreased the paw edema at the 5th h after λ-Carr administration in paw edema. We also demonstrated TL significantly attenuated the malondialdehyde (MDA) level in the edema paw at the 5th h after Carr injection. TL decreased the NO and TNF-α levels on the serum level at the 5th h after Carr injection. Western blotting revealed that TL decreased Carr-induced iNOS and COX-2 expressions at the 5th h in the edema paw. The anti-inflammatory mechanisms of TL might be related to the decrease in the level of iNOS, COX-2, IκBα, and MAPK pathway through the suppression of TNF-α, IL-1ß, and IL-6.

Curcumin-loaded nanoparticles enhance apoptotic cell death of U2OS human osteosarcoma cells through the Akt-Bad signaling pathway.

Curcumin has potential anticancer activity and has been shown to be involved in several signaling pathways including differentiation and apoptosis. Our previous study showed that water-soluble PLGA curcumin nanoparticles (Cur-NPs) triggered apoptotic cell death through regulation of the function of MDR1 and the production of reactive oxygen species (ROS) in cisplatin-resistant human oral cancer CAR cells. In this study, we investigated the anti-proliferative effects of Cur-NPs on human osteosarcoma U2OS cells. The morphology of Cur-NPs showed spherical shape by TEM analysis. The encapsulation efficiency of curcumin in Cur-NPs prepared by single emulsion was 90.5 ± 3.0%. Our results demonstrated that the curcumin fragments on the mass spectrum of Cur-NPs and the peaks of curcumin standard could be found on the Cur-NPs spectrum by 1H-NMR spectra analysis. Cur-NPs induced anti-proliferative effects and apoptosis in U2OS cells. Compared to the untreated U2OS cells, more detectable amount of Cur-NPs was found inside the treated U2OS cells. Cur-NPs induced DNA fragmentation and apoptotic bodies in U2OS cells. Both the activity and the expression levels of caspases-3/-7 and caspase-9 were elevated in the treated U2OS cells. Cur-NPs upregulated the protein expression levels of cleaved caspase-3/caspase-9, cytochrome c, Apaf-1 and Bad and downregulated the protein expression level of p-Akt in U2OS cells. These results suggest Cur-NPs are effective in enhancing apoptosis in human osteosarcoma cells and thus could provide potential for cancer therapeutics.

Phenethyl isothiocyanate suppresses EGF-stimulated SAS human oral squamous carcinoma cell invasion by targeting EGF receptor signaling.

Phenethyl isothiocyanate (PEITC) is a natural compound that is involved in chemoprevention as well as inhibition of cell growth and induction of apoptosis in several types of cancer cells. Previous studies have revealed that PEITC suppresses the invasion of AGS gastric and HT-29 colorectal cancer cells. However, the effects of PEITC on the metastasis of SAS oral cancer cells remain to be determined. Our results showed that PEITC treatment inhibited the invasion of EGF-stimulated SAS cells in a concentration-dependent manner, but appeared not to affect the cell viability. The expression and enzymatic activities of matrix metalloprotease-2 (MMP-2) and matrix metalloprotease-9 (MMP-9) were suppressed by PEITC. Concomitantly, we observed an increase in the protein expression of both tissue inhibitor of metalloproteinase-1 (TIMP-1) and -2 (TIMP-2) in treated cells. Furthermore, PEITC treatments decreased the protein phosphorylation of epidermal growth factor receptor (EGFR) and downstream signaling proteins including PDK1, PI3K (p85), AKT, phosphorylated IKK and IκB to inactivate NF-κB for the suppression of MMP-2 and MMP-9 expression. In addition, PEITC can trigger the MAPK signaling pathway through the increase in phosphorylated p38, JNK and ERK in treated cells. Our data indicate that PEITC is able to inhibit the invasion of EGF-stimulated SAS oral cancer cells by targeting EGFR and its downstream signaling molecules and finally lead to the reduced expression and enzymatic activities of both MMP-2 and MMP-9. These results suggest that PEITC is promising for the therapy of oral cancer metastasis.

Chemical characterization and in vivo anti-inflammatory activities of Actinidia callosa var. ephippioides via suppression of proinflammatory cytokines.

Actinidia callosa var. ephippioides (ACE) has been widely used to treat anti-pyretic, antinociceptive, anti-inflammation, abdominal pain and fever in Taiwan. This study aims to determine the mechanism of anti-inflammatory activities of ethyl acetate fraction of ACE (EA-ACE) using a model of λ-carrageenan (Carr)-induced paw edema in mouse model. In HPLC analysis, chemical characterization of EA-ACE was established. In order to investigate the anti-inflammatory mechanism of EA-ACE, we have detected the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) and the levels of malondialdehyde (MDA) in the paw edema. Serum NO, tumor necrosis factor α (TNF-α), and interleukin-1ß (IL-1ß) were evaluated. Chemical characterization from HPLC indicated that EA-ACE contains betulinic acid, ursolic acid and oleanolic acid. In the anti-inflammatory test, EA-ACE decreased the paw edema after Carr administration, increased the activities of CAT, SOD, and GPx and decreased the MDA level in the edema paw at the 5th hr after Carr injection. EA-ACE affects the serum NO, TNF-α, and IL-1ß levels at the 5th hr after Carr injection. EA-ACE decreased Carr-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions by Western blotting. Actinidia callosa var. ephippioides have the potential to provide a therapeutic approach to inflammation-associated disorders.

Antioxidant and anti-inflammatory activities of aqueous extract of Centipeda minima.

ETHNOPHARMACOLOGICAL RELEVANCE: Centipeda minima (L.) is traditionally used in Chinese folk medicine for the treatments of rhinitis, sinusitis, relieving pain, reducing swelling, and treating cancer for a long history in Taiwan. However, there is no scientific evidence which supports the use in the literature. AIM OF THE STUDY: The aim of this study was to evaluate the antioxidant and anti-inflammatory activities of the aqueous extract of Centipeda minima (ACM). MATERIALS AND METHODS: The following activities were investigated: antioxidant activities [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), DPPH (1,1-diphenyl-2-picrylhydrazyl)], and anti-inflammatory [lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW264.7 macrophages and paw-edema induced by λ-carrageenan (Carr)]. We also investigated the anti-inflammatory mechanism of ACM via studies of the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) and the levels of malondialdehyde (MDA) in the edema paw. Serum NO, tumor necrosis factor α (TNF-α), and interleukin-1ß (IL-1ß) were also measured in vivo. In HPLC analysis, the fingerprint chromatogram of ACM was established. RESULTS: ACM showed the highest TEAC and DPPH radical scavenging activities, respectively. ACM also had highest contents of polyphenol and flavonoid contents. We evaluated that ACM and the reference compound of protocatechualdehyde and caffeic acid decreased the LPS-induced NO production in RAW264.7 cells. Administration of ACM showed a concentration dependent inhibition on paw edema development after Carr treatment in mice. The anti-inflammatory effects of ACM could be via NO, TNF-α, and IL-1ß suppressions and associated with the increase in the activities of antioxidant enzymes. Western blotting revealed that ACM decreased Carr-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions. CONCLUSIONS: Anti-inflammatory mechanisms of ACM might be correlated to the decrease in the level of Malondialdehyde (MDA), iNOS, and COX-2 via increasing the activities of CAT, SOD, and GPx in the edema paw. Overall, the results showed that ACM demonstrated antioxidant and anti-inflammatory activity, which supports previous claims of the traditional use for inflammation and pain.

Kaempferol suppresses cell metastasis via inhibition of the ERK-p38-JNK and AP-1 signaling pathways in U-2 OS human osteosarcoma cells.

Kaempferol is a natural flavonoid that possesses anti-proliferative and apoptosis-inducing activities in several cancer cell lines. In the present study, we investigated the anti-metastatic activity of kaempferol and its molecular mechanism(s) of action in human osteosarcoma cells. Kaempferol displayed inhibitory effects on the invasion and adhesion of U-2 osteosarcoma (OS) cells in a concentration-dependent manner by Matrigel Transwell assay and cell adhesion assay. Kaempferol also inhibited the migration of U-2 OS cells in a concentration-dependent manner at different treatment time points by wound-healing assay. Additional experiments showed that kaempferol treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase (MMP)-2, MMP-9 and urokinase plasminogen activator (uPA) by gelatin and casein-plasminogen zymography assays and western blot analyses. Kaempferol also downregulated the mRNA levels of MMP-2 and MMP-9 by quantitative PCR analyses. Furthermore, kaempferol was able to reduce the protein phosphorylation of ERK, p38 and JNK by western blotting. By electrophoretic mobility-shift assay (EMSA), we demonstrated that kaempferol decreased the DNA binding activity of AP-1, an action likely to result in the reduced expression of MMP-2, MMP-9 and uPA. Collectively, our data showed that kaempferol attenuated the MAPK signaling pathways including ERK, JNK and p38 and resulted in the decreased DNA binding ability of AP-1, and hence, the downregulation in the expression and enzymatic activities of MMP-2, MMP-9 and uPA, contributing to the inhibition of metastasis of U-2 OS cells. Our results suggest a potential role of kaempferol in the therapy of tumor metastasis of OS.

Antioxidant and anti-inflammatory properties of Taiwanese yam (Dioscorea japonica Thunb. var. pseudojaponica (Hayata) Yamam.) and its reference compounds.

Dioscorea japonica Thunb. var. pseudojaponica (DP) is consumed as food and widely used in traditional Chinese medicine in Taiwan. The aims of this study are to investigate the antioxidant and anti-inflammatory effects of ethanol extract of DP (EDP) and its reference compounds. Fingerprint chromatogram from HPLC indicated that EDP contains gallic acid and vanillic acid. EDP was evaluated for its antioxidant effects and LPS-induced nitrite oxide (NO) production in RAW264.7 cells. EDP decreased the LPS-induced NO production and expressions of iNOS and COX-2 in RAW264.7 cells. In-vivo anti-inflammatory activities of EDP were assessed in mouse paw oedema induced by λ-carrageenan (Carr). We investigated the antioxidant mechanism of EDP via studies of the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) and the levels of malondialdehyde (MDA) in the oedematous paw. The results showed that EDP might be a natural antioxidant and anti-inflammatory agent.

Curcumin-loaded nanoparticles induce apoptotic cell death through regulation of the function of MDR1 and reactive oxygen species in cisplatin-resistant CAR human oral cancer cells.

Curcumin is a polyphenolic compound which possesses anticancer potential. It has been shown to induce cell death in a variety of cancer cells, however, its effect on CAL27­cisplatin-resistant human oral cancer cells (CAR cells) has not been elucidated to date. The low water solubility of curcumin which leads to poor bioavailability, however, has been highlighted as a major limiting factor. In this study, we utilized water-soluble PLGA curcumin nanoparticles (Cur-NPs), and investigated the effects of Cur-NPs on CAR cells. The results showed Cur-NPs induced apoptosis in CAR cells but exhibited low cytotoxicity to normal human gingival fibroblasts (HGFs) and normal human oral keratinocytes (OKs). Cur-NPs triggered DNA concentration, fragmentation and subsequent apoptosis. Compared to untreated CAR cells, a more detectable amount of Calcein-AM accumulation was found inside the treated CAR cells. Cur-NPs suppressed the protein and mRNA expression levels of MDR1. Both the activity and the expression levels of caspase-3 and caspase-9 were elevated in the treated CAR cells. The Cur-NP-triggered apoptosis was blocked by specific inhibitors of pan-caspase (z-VAD-fmk), caspase-3 (z-DEVD-fmk), caspase-9 (z-LEHD-fmk) and antioxidant agent (N-acetylcysteine; NAC). Cur-NPs increased reactive oxygen species (ROS) production, upregulated the protein expression levels of cleaved caspase-3/caspase-9, cytochrome c, Apaf-1, AIF, Bax and downregulated the protein levels of Bcl-2. Our results suggest that Cur-NPs triggered the intrinsic apoptotic pathway through regulating the function of multiple drug resistance protein 1 (MDR1) and the production of reactive oxygen species (ROS) in CAR cells. Cur-NPs could be potentially efficacious in the treatment of cisplatin-resistant human oral cancer.

Hepatoprotective effects of eburicoic acid and dehydroeburicoic acid from Antrodia camphorata in a mouse model of acute hepatic injury.

The hepatoprotective effects of eburicoic acid (TR1) and dehydroeburicoic acid (TR2) from Antrodia camphorata (AC) against carbon tetrachloride (CCl4)-induced liver damage were investigated in mice. TR1 and TR2 was administered intraperitoneally (i.p.) for 7 days prior to the administration of CCl4. Pretreatment with TR1 and TR2 prevented the elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and liver lipid peroxides in CCl4-treated mice. The activities of antioxidant enzymes [catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)], nitric oxide (NO) production, and tumour necrosis factor-alpha (TNF-α) were decreased after the treatment with TR1 and TR2 in CCl4-treated mice. Western blotting revealed that TR1 and TR2 significantly decreased inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions and increased the expression of cytochrome P4502E1 (CYP2E1) in CCl4-treated mice. Therefore, we speculate that TR1 and TR2 protect the liver from CCl4-induced hepatic damage via antioxidant and anti-inflammatory mechanisms.

Apoptosis triggered by vitexin in U937 human leukemia cells via a mitochondrial signaling pathway.

Vitexin, a lignan compound, has been shown to exert apoptotic actions on human breast cancer cell lines and to have anti-inflammatory activities. Nevertheless, there is currently no study addressing the effects of vitexin on the induction of apoptosis in U937 human leukemia cells. The aim of this study was to determine the anticancer effects and molecular mechanisms of vitexin on U937 leukemia cells. We showed that vitexin can potently induce programmed cell death in U937 leukemia cell growth as well as morphological changes that were examined by MTT assay and phase contrast microscopy, respectively. The DNA content and the levels of mitochondrial membrane potential (∆Ψm) were determined by flow cytometric analysis. The cell cycle arrest-regulated and apoptosis-associated protein levels were measured by western blotting. Vitexin-triggered apoptosis was accompanied by a decrease of the level of ∆Ψm and the percentage of viability and provoked apoptosis in U937 cells. The downregulation of the protein level for Bcl-2 with the simultaneous upregulation of caspase-3 and -9 protein expression in U937 cells were observed after treatment with vitexin. Therefore, our data provide a potential mechanism for the chemopreventive activity of vitexin, and we suggest that vitexin may serve as a therapeutic agent for the treatment of human leukemia.

Epigallocatechin gallate sensitizes CAL-27 human oral squamous cell carcinoma cells to the anti-metastatic effects of gefitinib (Iressa) via synergistic suppression of epidermal growth factor receptor and matrix metalloproteinase-2.

Human head and neck squamous cell carcinoma (HNSCC) is a major cause of cancer-related death during the last decade due to its related metastasis and poor treatment outcomes. Gefitinib (Iressa), a tyrosine kinase inhibitor has been reported to reduce the metastatic abilities of oral cancer. Previous studies have shown that epigallocatechin gallate (EGCG), a green tea polyphenol, possesses cancer chemopreventive and anticancer activity. However, the mechanisms involved in the suppression of invasion and metastasis of human oral cancer cells following co-incubation with gefitinib and EGCG remain poorly understood. In the present study, we attempted to investigate the synergistic effects of a combined treatment of gefitinib and EGCG in CAL-27 cells in vitro and to elucidate the underlying molecular mechanisms associated with the supression of cell migration and invasion. In the present study, we found that the individual treatments or the combined treatment of gefitinib and EGCG synergistically inhibited the invasion and migration of CAL-27 cells using Transwell invasion and wound-healing scratch assays, respectively. Similarly, gefitinib in combination with EGCG synergistically attenuated enzymatic activity and the protein expression of MMP-2 in CAL-27 cells. Furthermore, individual or combined treatment with EGCG and gefitinib suppressed the protein expression of p-EGFR and the phosphorylated protein levels of ERK, JNK, p38 and AKT and displayed inhibitory effects on metastatic ability of CAL-27 cells. Combined effects of EGCG and gefitinib-altered anti-metastatic actions for related gene expression were observed using DNA microarray analysis. Importantly, EGCG sensitizes CAL-27 cells to gefitinib-suppressed phosphorylation of epidermal growth factor receptor (EGFR in vitro. Taken together, our results suggest that the synergistic suppression of the metastatic ability of CAL-27 cells after EGCG and gefitinib individual or combined treatment are mediated through mitogen-activated protein kinase (MAPK) signaling. Our novel findings provide potential insights into the mechanism involved with synergistic responses of gefitinib and EGCG against the progression of oral cancer.