Let-7g Upregulation Attenuated the KRAS-PI3K-Rac1-Akt Axis-Mediated Bioenergetic Functions.

The aberrant activation of signaling pathways contributes to cancer cells with metabolic reprogramming. Thus, targeting signaling modulators is considered a potential therapeutic strategy for cancer. Subcellular fractionation, coimmunoprecipitation, biochemical analysis, and gene manipulation experiments revealed that decreasing the interaction of kirsten rat sarcoma viral oncogene homolog (KRAS) with p110α in lipid rafts with the use of naringenin (NGN), a citrus flavonoid, causes lipid raft-associated phosphatidylinositol 3-kinase (PI3K)-GTP-ras-related C3 botulinum toxin substrate 1 (Rac1)-protein kinase B (Akt)-regulated metabolic dysfunction of glycolysis and mitochondrial oxidative phosphorylation (OXPHOS), leading to apoptosis in human nasopharyngeal carcinoma (NPC) cells. The use of lethal-7g (let-7g) mimic and let-7g inhibitor confirmed that elevated let-7g resulted in a decrease in KRAS expression, which attenuated the PI3K-Rac1-Akt-BCL-2/BCL-xL-modulated mitochondrial energy metabolic functions. Increased let-7g depends on the suppression of the RNA-specificity of monocyte chemoattractant protein-induced protein-1 (MCPIP1) ribonuclease since NGN specifically blocks the degradation of pre-let-7g by NPC cell-derived immunoprecipitated MCPIP1. Converging lines of evidence indicate that the inhibition of MCPIP1 by NGN leads to let-7g upregulation, suppressing oncogenic KRAS-modulated PI3K-Rac1-Akt signaling and thereby impeding the metabolic activities of aerobic glycolysis and mitochondrial OXPHOS.

Allyl isothiocyanate inhibits cell migration and invasion in human gastric cancer AGS cells via affecting PI3K/AKT and MAPK signaling pathway in vitro.

Metastasis is commonly occurred in gastric cancer, and it is caused and responsible for one of the major cancer-related mortality in gastric cancer patients. Allyl isothiocyanate (AITC), a natural product, exhibits anticancer activities in human many cancer cells, including gastric cancer. However, no available report shows AITC inhibits gastric cancer cell metastasis. Herein, we evaluated the impact of AITC on cell migration and invasion of human gastric cancer AGS cells in vitro. AITC at 5-20 µM did not induce significant cell morphological damages observed by contrast-phase microscopy but decreased cell viability assayed by flow cytometry. After AGS cells were further examined by atomic force microscopy (AFM), which indicated AITC affected cell membrane and morphology in AGS cells. AITC significantly suppressed cell motility examined by scratch wound healing assay. The results of the gelatin zymography assay revealed that AITC significantly suppressed the MMP-2 and MMP-9 activities. In addition, AITC suppressed cell migration and invasion were performed by transwell chamber assays at 24 h in AGS cells. Furthermore, AITC inhibited cell migration and invasion by affecting PI3K/AKT and MAPK signaling pathways in AGS cells. The decreased expressions of p-AKTThr308 , GRB2, and Vimentin in AGS cells also were confirmed by confocal laser microscopy. Our findings suggest that AITC may be an anti-metastasis candidate for human gastric cancer treatment.

Bisdemethoxycurcumin Induces Cell Apoptosis and Inhibits Human Brain Glioblastoma GBM 8401/Luc2 Cell Xenograft Tumor in Subcutaneous Nude Mice In Vivo.

Bisdemethoxycurcumin (BDMC) has biological activities, including anticancer effects in vitro; however, its anticancer effects in human glioblastoma (GBM) cells have not been examined yet. This study aimed to evaluate the tumor inhibitory effect and molecular mechanism of BDMC on human GBM 8401/luc2 cells in vitro and in vivo. In vitro studies have shown that BDMC significantly reduced cell viability and induced cell apoptosis in GBM 8401/luc2 cells. Furthermore, BDMC induced apoptosis via inhibited Bcl-2 (anti-apoptotic protein) and increased Bax (pro-apoptotic proteins) and cytochrome c release in GBM 8401/luc2 cells in vitro. Then, twelve BALB/c-nude mice were xenografted with human glioblastoma GBM 8401/luc2 cancer cells subcutaneously, and the xenograft nude mice were treated without and with BDMC (30 and 60 mg/kg of BDMC treatment) every 3 days. GBM 8401/luc2 cell xenografts experiment showed that the growth of the tumors was significantly suppressed by BDMC administration at both doses based on the reduction of tumor size and weights. BDMC did not change the body weight and the H&E histopathology analysis of liver samples, indicating that BDMC did not induce systemic toxicity. Meanwhile, treatment with BDMC up-regulated the expressions of BAX and cleaved caspase-3, while it down-regulated the protein expressions of Bcl-2 and XIAP in the tumor tissues compared with the control group. This study has demonstrated that BDMC presents potent anticancer activity on the human glioblastoma GBM 8401/luc2 cell xenograft model by inducing apoptosis and inhibiting tumor cell proliferation and shows the potential for further development to the anti-GBM cancer drug.

Ouabain Induces DNA Damage in Human Osteosarcoma U-2 OS Cells and Alters the Expression of DNA Damage and DNA Repair-associated Proteins.

BACKGROUND/AIM: Ouabain, isolated from natural plants, exhibits anticancer activities; however, no report has presented its mechanism of DNA damage induction in human osteosarcoma cancer cells in vitro. The aim of this study was to investigate whether ouabain induces DNA damage and repair, accompanied with molecular pathways in human osteosarcoma cancer U-2 OS cells in vitro. MATERIALS AND METHODS: The percentage of viable cell number was measured by flow cytometric assay; DNA damage was assayed by DAPI staining, comet assay, and agarose gel electrophoresis. DNA damage and repair associated protein expressions were assayed by western blotting assays. RESULTS: Ouabain reduced total cell viability, induced chromatin condensation, DNA fragmentation, and DNA damage in U-2 OS cells. Ouabain increased p-ATMSer1981, p-ATRSer428, and p53 at 2.5-10 µM, increased p-p53Ser15 at 10 µM; however, it decreased p-MDM2Ser166 at 2.5-10 µM. Ouabain increased p-H2A.XSer139, MDC-1, and PARP at 2.5-10 µM and BRCA1 at 5-10 µM; however, it decreased DNA-PK and MGMT at 2.5-10 µM in U-2 OS cells at 48 h treatment. Ouabain promoted expression and nuclear translocation of p-H2A.XSer139 in U-2 OS cells and this was confirmed by confocal laser microscopy. CONCLUSION: Ouabain reduced total viable cell number through triggering DNA damage and altering the protein expression of DNA damage and repair system in U-2 OS cells in vitro.

Benzyl Isothiocyanate Induces Apoptotic Cell Death Through Mitochondria-dependent Pathway in Gefitinib-resistant NCI-H460 Human Lung Cancer Cells In Vitro.

BACKGROUND/AIM: Gefitinib is used to treat patients with lung cancer, but in some patients, the disease becomes gefitinib-resistant. Benzyl isothiocyanate (BITC), found in cruciferous vegetables, has shown anticancer activity in many human cancer cell lines. However, the effects of BITC on gefitinib-resistant NCI-H460 lung cancer cells in vitro have not been investigated. MATERIALS AND METHODS: The effects of BITC on gefitinib-resistant NCI-H460 lung cancer cells were investigated in vitro. Flow cytometric assay was used for determining the total viable cell number, apoptotic cell death, the production of reactive oxygen species (ROS) and Ca2+, mitochondriaI membrane potential (Ψm) and caspase-3, -8 and -9 activities. Furthermore, 4', 6-diamidino-2-phenylindole staining was used to examine chromatin condensation in NCI-H460 and NCI-H460/G cells. RESULTS: BITC reduced total viable cell number via the induction of apoptotic cell death, that was also confirmed by annexin V/propidium iodide double staining assay. BITC increased ROS and Ca2+ production, reduced Ψm and increased caspase-3, -8 and -9 activities in both NCI-H460 and NCI-H460/G cells. Western blotting assay also showed that BITC increased expression of cleaved caspase-3 and -9, cytochrome c, BCL2-associated X protein, endonuclease G, poly (ADP-ribose) polymerase, growth arrest and DNA-damage protein 153, caspase-7 and activating transcription factor 6 alpha, but reduced apoptosis-inducing factor and caspase-9, BH3-interacting domain death agonist, calpain 1, glucose-regulated protein 78 and inositol requiring enzyme 1 alpha in NCI-H460/G cells. CONCLUSION: BITC-induced apoptotic cell death appears to occur via caspase- and mitochondria-dependent pathways in both cell lines.

Tetrandrine suppresses adhesion, migration and invasion of human colon cancer SW620 cells via inhibition of nuclear factor-κB, matrix metalloproteinase-2 and matrix metalloproteinase-9 signaling pathways.

Tetrandrine (TET) exhibits biological activities, including anticancer activity. In Chinese medicine, TET has been used to treat hypertensive and arrhythmic conditions and has been demonstrated to induce cytotoxic effects on human cancer cell lines. However, to the best of the author's knowledge, no previous studies have revealed that TET affects cell metastasis in SW620 human colon cancer cells. The present study demonstrated that TET decreased the cell number and inhibited cell adhesion and mobility of SW620 cells. Furthermore, a wound healing assay was performed to demonstrate that TET suppressed cell movement, and Transwell chamber assays were used to reveal that TET suppressed the cell migration and invasion of SW620 cells. Western blotting demonstrated that TET significantly reduced protein expression levels of SOS Ras/Rac guanine nucleotide exchange factor 1, phosphatidylinositol 3-kinase, growth factor receptor bound protein 2, phosphorylated (p)-c Jun N-terminal kinase 1/2, p-p38, p38, 14-3-3, Rho A, ß-catenin, nuclear factor-κB p65, signal transducer and activator of transcription-1 and cyclooxygenase-2, in comparison with untreated SW620 cells. Overall, the results of the present study suggested that TET may be used as a novel anti-metastasis agent for the treatment of human colon cancer in the future.

Tetrandrine Induces Apoptosis in Human Nasopharyngeal Carcinoma NPC-TW 039 Cells by Endoplasmic Reticulum Stress and Ca2+/Calpain Pathways.

Tetrandrine is an alkaloid extracted from a traditional China medicine plant, and is considered part of food therapy as well. In addition, it has been widely reported to induce apoptotic cell death in many human cancer cells. However, the mechanism of Tetrandrine on human nasopharyngeal carcinoma cells (NPC) is still questioned. In our study, we examined whether Tetrandrine can induce apoptosis of NPC-TW 039 cells. We found that cell morphology was changed after treatment with different concentrations of Tetrandrine. Further, we indicated that the NPC-TW 039 cells viability decreased in a Tetrandrine dose-dependent manner. We also found that tetrandrine induced cell cycle arrest in G0/G1 phase. Tetrandrine induced DNA condensation by DAPI staining as well. In addition, we found that Tetrandrine induced Ca2+ release in the cytosol. At the same time, endoplasmic reticulum (ER) stress occurred. Then we used western blotting to examine the protein expression which is associated with mitochondria-mediated apoptotic pathways and caspase-dependent pathways. To further examine whether Ca2+ was released or not with Tetrandrine induced-apoptosis, we used the chelator of Ca2+ and showed that cell viability increased. At the same time, caspase-3 expression was decreased. Furthermore, confocal microscopy examination revealed that Tetrandrine induced expression of ER stress-related proteins GADD153 and GRP78. Our results indicate that Tetrandrine induces apoptosis through calcium-mediated ER stress and caspase pathway in NPC-TW 039 cells. In conclusion, Tetrandrine may could be used for treatment of human nasopharyngeal carcinoma in future.

Benzyl isothiocyanate and phenethyl isothiocyanate inhibit murine melanoma B16F10 cell migration and invasion in vitro.

Benzyl isothiocyanate (BITC), and phenethyl isothiocyanate (PEITC) have been demonstrated to induce anticancer function in many human cancer cells and also inhibit cancer cell migration and invasion. However, there are no studies that show BITC and PEITC to inhibit cell migration and invasion in mouse melanoma B16F10 cells. In this study, we investigated anti-metastasis effects of BITC and PEITC in melanoma cancer cells in vitro. Under sub-lethal concentrations (from 1, 2.5 up to 5 µM), BITC and PEITC significantly inhibited cell mobility, migration and invasion nature of B16F10 cells. Gelatin zymography assay also showed that BITC and PEITC inhibited matrix metalloproteinase-2 (MMP-2) activity in B16F10 cells. PEITC reduced MAPK signaling associated proteins such as p-ERK1/2, p-p38 and p-JNK1/2 but BITC increased those MAPK signaling associated proteins. BITC and PEITC both suppressed the expression of RhoA, Ras, and SOS-1, however, PEITC increased FAK and GRB2 but BITC increased FAK at 48 h. Furthermore, PEITC decreased the expression of MMP-2 and tissue inhibitors of matrix metalloproteinases (TIMP) but BITC increased them. PEITC inhibited NF-κB protein levels and DNA binding which was confirmed by electrophoretic mobility shift (EMSA) assay. Based on these observations, we suggest that BITC and PEITC can be used in anti-metastasis of melanoma cells in the future.

Ouabain impairs cell migration, and invasion and alters gene expression of human osteosarcoma U-2 OS cells.

Ouabain, the specific Na+ /K+ -ATPase blocker, has biological activity including anti-proliferative and anti-metastasis effects in cancer cell. There is no study to show ouabain inhibiting cell migration and invasion in human osteosarcoma U-2 OS cells. Thus, we investigated the effect of ouabain on the cell migration and invasion of human osteosarcoma U-2 OS cells. Results indicated that ouabain significantly decreased the percentage of viable cells at 2.5-5.0 µM, thus, we selected 0.25-1.0 µM for inhibiting studies. Ouabain inhibited cell migration, invasion and the enzymatic activities of MMP-2, and also affected the expression of metastasis-associated protein in U-2 OS cells. The cDNA microarray assay indicated that CDH1, TGFBR3, SHC3 and MAP2K6 metastasis-related genes were increased, but CCND1, JUN, CDKN1A, TGFB1, 2 and 3, SMAD4, MMP13, MMP2 and FN1 genes were decreased. These findings provide more information regarding ouabain inhibited cell migration and invasion and associated gene expressions in U-2 OS cells after exposed to ouabain.

Cantharidin alters the expression of genes associated with the NKG2D-associated immune response in TSGH-8301 human bladder carcinoma cells.

Cantharidin (CTD) is a natural toxin in beetles of the Mylabris genus (blister beetle), which has been revealed to induce cell death in various types of human cancer cells. However, to the best of our knowledge, no previous studies have investigated the effect of CTD on the expression of genes and their associated signaling pathways in human bladder carcinoma cells. In the present study, CTD-induced cell morphological changes and apoptosis were observed using phase-contrast microscopy and the terminal deoxynucleotidyl transferase dUTP nick end labeling assay, respectively, in TSGH-8301 human bladder carcinoma cells. In addition, a complementary DNA microarray analysis demonstrated that CTD treatment led to a >2-fold upregulation of 269 genes. For example, the DNA damage-associated gene DNA-damage-inducible transcript 3 had a 4.75-fold upregulation. Furthermore, another 286 genes were >2-fold downregulated in response to CTD treatment. Matrix-remodeling associated 5, which is associated with cell migration and invasion, was downregulated 7.98-fold.

Fisetin-induced apoptosis of human oral cancer SCC-4 cells through reactive oxygen species production, endoplasmic reticulum stress, caspase-, and mitochondria-dependent signaling pathways.

Oral cancer is one of the cancer-related diseases in human populations and its incidence rates are rising worldwide. Fisetin, a flavonoid from natural products, has been shown to exhibit anticancer activities in many human cancer cell lines but the molecular mechanism of fisetin-induced apoptosis in human oral cancer cells is still unclear; thus, in this study, we investigated fisetin-induced cell death and associated signal pathways on human oral cancer SCC-4 cells in vitro. We examined cell morphological changes, total viable cells, and cell cycle distribution by phase contrast microscopy and flow cytometry assays. Reactive oxygen species (ROS), Ca2+ , mitochondria membrane potential (ΔΨm ), and caspase-8, -9, and -3 activities were also measured by flow cytometer. Results indicate that fisetin induced cell death through the cell morphological changes, caused G2/M phase arrest, induction of apoptosis, promoted ROS and Ca2+ production, and decreased the level of ΔΨm and increased caspase-3, -8, and -9 activities in SCC-4 cells. DAPI staining and DNA gel electrophoresis were also used to confirm fisetin-induced cell apoptosis in SCC-4 cells. Western blotting also found out that Fisetin increased the proapoptotic proteins such as Bax and Bid and decreased the antiapoptotic proteins such as Bcl-2. Furthermore, results also showed that Fisetin increased the cytochrome c, AIF, and Endo G release from mitochondria in SCC-4 cells. We also used ATF-6α, ATF-6ß, GADD153, and GRP78 which indicated that fisetin induced cell death through ER stress. Based on those observations, we suggest that fisetin induced cell apoptosis through ER stress, mitochondria-, and caspase-dependent pathways.

Sulforaphane Induces Cell Death Through G2/M Phase Arrest and Triggers Apoptosis in HCT 116 Human Colon Cancer Cells.

Sulforaphane (SFN), an isothiocyanate, exists exclusively in cruciferous vegetables, and has been shown to possess potent antitumor and chemopreventive activity. However, there is no available information that shows SFN affecting human colon cancer HCT 116 cells. In the present study, we found that SFN induced cell morphological changes, which were photographed by contrast-phase microscopy, and decreased viability. SFN also induced G2/M phase arrest and cell apoptosis in HCT 116 cells, which were measured with flow cytometric assays. Western blotting indicated that SFN increased Cyclin A, cdk 2, Cyclin B and WEE1, but decreased Cdc 25C, cdk1 protein expressions that led to G2/M phase arrest. Apoptotic cell death was also confirmed by Annexin V/PI and DAPI staining and DNA gel electrophoresis in HCT 116 cells after exposure to SFN. The flow cytometric assay also showed that SFN induced the generation of reactive oxygen species (ROS) and Ca[Formula: see text] and decreased mitochondria membrane potential and increased caspase-8, -9 and -3 activities in HCT 116 cell. Western blotting also showed that SFN induced the release of cytochrome c, and AIF, which was confirmed by confocal microscopy examination. SFN induced ER stress-associated protein expression. Based on those observations, we suggest that SFN may be used as a novel anticancer agent for the treatment of human colon cancer in the future.

18α-Glycyrrhetinic Acid Induces Apoptosis of HL-60 Human Leukemia Cells through Caspases- and Mitochondria-Dependent Signaling Pathways.

In this study we investigate the molecular mechanisms of caspases and mitochondria in the extrinsic and intrinsic signal apoptosis pathways in human leukemia HL-60 cells after in vitro exposure to 18α-glycyrrhetinic acid (18α-GA). Cells were exposed to 18α-GA at various concentrations for various time periods and were harvested for flow cytometry total viable cell and apoptotic cell death measurements. Cells treated with 18α-GA significantly inhibited cell proliferation and induced cell apoptosis in a dose-dependent manner, with an IC50 value of 100 µM at 48 h. The cell growth inhibition resulted in induction of apoptosis and decreased the mitochondria membrane potential (ΔΨm) and increased caspase-8, -9 and -3 activities. Furthermore, cytochrome c and AIF were released from mitochondria, as shown by western blotting and confirmed by confocal laser microscopy. Western blotting showed that 18α-GA increased the levels of pro-apoptotic proteins such as Bax and Bid and decreased the anti-apoptotic proteins such as Bcl-2 and Bcl-xl, furthermore, results also showed that 18α-GA increased Fas and Fas-L which are associated with surface death receptor in HL-60 cells. Based on those observations, the present study supports the hypothesis that 18α-GA-induced apoptosis in HL-60 cells involves the activation of the both extrinsic and intrinsic apoptotic pathways.

Tetrandrine induces apoptosis Via caspase-8, -9, and -3 and poly (ADP ribose) polymerase dependent pathways and autophagy through beclin-1/ LC3-I, II signaling pathways in human oral cancer HSC-3 cells.

Tetrandrine is a bisbenzylisoquinoline alkaloid that was found in the Radix Stephania tetrandra S Moore. It had been reported to induce cytotoxic effects on many human cancer cells. In this study, we investigated the cytotoxic effects of tetrandrine on human oral cancer HSC-3 cells in vitro. Treatments of HSC-3 cells with tetrandrine significantly decreased the percentage of viable cells through the induction of autophagy and apoptosis and these effects are in concentration-dependent manner. To define the mechanism underlying the cytotoxic effects of tetrandrine, we investigated the critical molecular events known to regulate the apoptotic and autophagic machinery. Tetrandrine induced chromatin condensation, internucleosomal DNA fragmentation, activation of caspases-3, -8, and -9, and cleavage of poly (ADP ribose) polymerase (PARP) that were associated with apoptosis, and it also enhanced the expression of LC3-I and -II that were associated with the induction of autophagy in human squamous carcinoma cell line (HSC-3) cells. Tetrandrine induced autophagy in HSC-3 cells was significantly attenuated by bafilomycin A1 (inhibitor of autophagy) pre-treatment that confirmed tetrandrine induced cell death may be associated with the autophagy. In conclusion, we suggest that tetrandrine induced cell death may be through the induction of apoptosis as well as autophagy in human oral cancer HSC-3 cells via PARP, caspases/Becline I/LC3-I/II signaling pathways.

Crude extract of Euphorbia formosana induces apoptosis of DU145 human prostate cancer cells acts through the caspase-dependent and independent signaling pathway.

Prostate cancer is the most frequently diagnosed malignancy in men and the second highest contributor of male cancer mortality. The crude extract of Euphorbia formosana (CEEF) has been used for treatment of different diseases but the cytotoxic effects of CEEF on human cancer cells have not been reported. The purpose of the present experiments was to determine effects of CEEF on cell cycle distribution and induction of apoptosis in DU145 human prostate cancer cells in vitro. Contrast-phase microscope was used for examining cell morphological changes. Flow cytometric assays were used for cell viability, cell cycle, apoptosis, reactive oxygen species, and Ca2+ production and mitochondria membrane potential (ΔΨm ). Western blotting was used for examining protein expression of cell cycle and apoptosis associated proteins. Real-time PCR was used for examining mRNA levels of caspase-3, -8, and -9, AIF, and Endo G. Confocal laser microscope was used to examine the translocation of AIF, Endo G, and cytochrome in DU145 cells after CEEF exposure. CEEF-induced cell morphological changes, decreased the percentage of viable cells, and induced S phase arrest and apoptosis in DU145 cells. Furthermore, CEEF promoted RAS and Ca2+ production and reduced ΔΨm levels. Real-time QPCR confirmed that CEEF promoted the mRNA expression of caspase-3 and -9, AIF and Endo G and we found that AIF and Endo G and cytochrome c were released from mitochondria. Taken together, CEEF-induced cytotoxic effects via ROS production, induced S phase arrest and induction of apoptosis through caspase-dependent and independent and mitochondria-dependent pathways in DU245 cancer cells. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1600-1611, 2016.

The suppressive activities of six sources of medicinal ferns known as gusuibu on heat-labile enterotoxin-induced diarrhea.

Diarrheal disease is one of the most important worldwide health problems. Enterotoxigenic Escherichia coli (ETEC) is the most frequently isolated enteropathogen in diarrheal diseases. In developing countries, a very large number of people, especially children, suffer from diarrhea. To combat this problem, World Health Organization has constituted the Diarrhea Diseases Control Program which guides studies on traditional medicinal practices and preventive measures. Gusuibu, a traditional folk medicine, has been claimed to heal certain types of diarrhea. However, so far no scientific study has been carried out on the anti-diarrheal mechanism of Gusiubu. The present study was performed to examine the suppressive activities of ethanol extracts of six sources of folk medicinal ferns used as Gusuibu on heat-labile enterotoxin (LT)-induced diarrhea. Inhibitory effects of six sources were evaluated on the ETEC LT subunit B (LTB) and monosialotetrahexosylganglioside (GMI) interaction by GM1-enzyme linked immunosorbent assay and patent mouse gut assay. Our results indicated that Drynaria fortunei had no anti-diarrheal effect, while, among the remaining five folk medicinal ferns, four belonging to family Davalliaceae had significant abilities on both the blocking of LTB and GM1 interaction and the inhibition of LT-induced diarrhea. In conclusion, these findings suggested the potential application of Gusuibu as an anti-diarrheal remedy.

Crude extract of Euphorbia formosana inhibits the migration and invasion of DU145 human prostate cancer cells: The role of matrix metalloproteinase-2/9 inhibition via the MAPK signaling pathway.

Prostate cancer is a common worldwide health problem in males with a poor prognosis due in part to tumor invasion and migration. The crude extract of Euphorbia formosana (CEEF) has been used for the treatment of numerous diseases, however, its effects on the migration and invasion of prostate cancer cells have yet to be examined. In the present study, we investigated the effects of CEEF on the migration and invasion of DU145 human prostate cancer cells in vitro. The wound healing assay and the Matrigel-uncoated migration assay were used to examine the migration of cancer cells. Western blotting was used to examine the levels of proteins associated with migration and invasion, and gelatin zymography was used to examine the secretion levels of matrix metalloproteinases-2 and -9 (MMP­2/9) from DU145 cells following exposure to CEEF. The results indicated that CEEF suppressed the migration and invasion of DU145 prostate cancer cells and that these effects are exerted in a concentration- and time-dependent manner. CEEF inhibited the ERK1/2, p38, JNK, SOS1, PKC, PI3K and MMP-2/9 protein expression in DU145 cells. The results demonstrated that CEEF suppressed the migration and invasion of DU145 cells through inhibition of the mitogen-activated protein kinase (MAPK) signaling pathway resulting in the inhibition of MMP-2/9 in DU145 human prostate cancer cells.

Phenethyl isothiocyanate (PEITC) promotes G2/M phase arrest via p53 expression and induces apoptosis through caspase- and mitochondria-dependent signaling pathways in human prostate cancer DU 145 cells.

Phenethyl isothiocyanate (PEITC), one of many compounds found in cruciferous vegetables, has been reported as a potential anticancer agent. In earlier studies, PEITC was shown to inhibit cell growth and induction of apoptosis in many cancer cell lines. However, no report has shown whether PEITC can induce apoptosis in human prostate cancer cells. Herein, we aimed to determine whether PEITC has anticancer activity in DU 145 human prostate cancer cells. As a result, we found that PEITC induced a dose-dependent decrease in cell viability through induction of cell apoptosis and cell cycle arrest in the G(2)/M phase of DU 145 cells. PEITC induced morphological changes and DNA damage in DU 145 cells. The induction of G(2)/M phase arrest was mediated by the increase of p53 and WEE1 and it reduced the level of CDC25C protein. The induction of apoptosis was mediated by the activation of caspase-8-, caspase-9- and caspase-3-depedent pathways. Results also showed that PEITC caused mitochondrial dysfunction, increasing the release of cytochrome c and Endo G from mitochondria, and led cell apoptosis through a mitochondria-dependent signaling pathway. This study showed that PEITC might exhibit anticancer activity and become a potent agent for human prostate cancer cells in the future.

The roles of AIF and Endo G in the apoptotic effects of benzyl isothiocyanate on DU 145 human prostate cancer cells via the mitochondrial signaling pathway.

It is well known that the response of cancer cells to chemotherapeutic drugs involves the activation of apoptotic pathways. Benzyl isothiocyanate (BITC) is an important compound found in plant food and has been shown to have anti-cancer effects on human cancer cells, but its effect on prostate cancer cells in vitro remains unknown. The aim of the present study was to investigate the effects of BITC on DU 145 human prostate cancer cells in order to clarify whether a time/concentration range for optimal BITC-induced apoptosis exists and to find the associated signaling pathway. Cell morphological changes, percentage of cell viability, DNA damage and apoptosis in DU 145 cells were examined by phase-contrast microscopy, flow cytometric assay, 4',6-diamidine-20-phenylindole dihydrochloride staining, comet assay and Western blotting analysis. The results indicate that BITC induces cell morphological changes, decreases the percentage of viable cells (induction of cell cytotoxicity), and induces DNA damage and apoptosis in DU 145 cells in a time- and dose-dependent manner. Flow cytometric assays indicated that BITC promoted reactive oxygen species and Ca2+ productions and decreased the levels of mitochondrial membrane potential (ΤYm), while the pre-treatment with N-acetylcysteine caused an increase in the percentage of viable cells. BITC also promoted caspase-3, -8 and -9 activities. Furthermore, when cells were pre-treated with the caspase-3 inhibitor and then treated with BITC, this led to an increase in the percentage of viable cells. Confocal laser microscopy examination indicated that BITC promoted the expression of AIF and Endo G, which were released from the mitochondria in DU 145 cells. In conclusion, BITC induces apoptosis in DU 145 cells through the release of AIF and Endo G from the mitochondria and also promotes caspase-3 activation.

Curcumin induces apoptosis in human non-small cell lung cancer NCI-H460 cells through ER stress and caspase cascade- and mitochondria-dependent pathways.

It has been reported that curcumin inhibited various types of cancer cells in vitro and in vivo. However, mechanisms of curcumin-inhibited cell growth and -induced apoptosis in human non-small cell lung cancer cells (NCI-H460) still remain unclear. In this study, NCI-H460 cells were treated with curcumin to determine its anticancer activity. Different concentrations of curcumin were used for different durations in NCI-H460 cells and the subsequent changes in the cell morphology, viability, cell cycle, mRNA and protein expressions were determined. Curcumin induced apoptotic morphologic changes in NCI-H460 cells in a dose-dependent manner. After curcumin treatment, BAX and BAD were up-regulated, BCL-2, BCL-X(L) and XIAP were down-regulated. In addition, reactive oxygen species (ROS), intracellular Ca(2+) and endoplasmic reticulum (ER) stress were increased in NCI-H460 cells after exposure to curcumin. These signals led to a loss of mitochondrial membrane potential (Delta Psi(m)) and culminated in caspase-3 activation. Curcumin-induced apoptosis was also stimulated through the FAS/caspase-8 (extrinsic) pathway and ER stress proteins, growth arrest- and DNA damage-inducible gene 153 (GADD153) and glucose-regulated protein 78 (GRP78) were activated in the NCI-H460 cells. Apoptotic cell death induced by curcumin was significantly reversed by pretreatment with ROS scavenger or caspase-8 inhibitor. Furthermore, the NCI-H460 cells tended to be arrested at the G(2)/M cell cycle stage after curcumin treatment and down-regulation of cyclin-dependent kinase 1 (CDK1) may be involved. In summary, curcumin exerts its anticancer effects on lung cancer NCI-H460 cells through apoptosis or cell cycle arrest.