Phenethyl isothiocyanate and irinotecan synergistically induce cell apoptosis in colon cancer HCT 116 cells in vitro.

Irinotecan (IRI), an anticancer drug to treat colon cancer patients, causes cytotoxic effects on normal cells. Phenethyl isothiocyanate (PEITC), rich in common cruciferous plants, has anticancer activities (induction of cell apoptosis) in many human cancer cells, including colon cancer cells. However, the anticancer effects of IRI combined with PEITC on human colon cancer cells in vitro were unavailable. Herein, the aim of this study is to focus on the apoptotic effects of the combination of IRI and PEITC on human colon cancer HCT 116 cells in vitro. Propidium iodide (PI) exclusion and Annexin V/PI staining assays showed that IRI combined with PEITC decreased viable cell number and induced higher cell apoptosis than that of IRI or PEITC only in HCT 116 cells. Moreover, combined treatment induced higher levels of reactive oxygen species (ROS) and Ca2+ than that of IRI or PEITC only. Cells pre-treated with N-acetyl-l-cysteine (scavenger of ROS) and then treated with IRI, PEITC, or IRI combined with PEITC showed increased viable cell numbers than that of IRI or PEITC only. IRI combined with PEITC increased higher caspase-3, -8, and -9 activities than that of IRI or PEITC only by flow cytometer assay. IRI combined with PEITC induced higher levels of ER stress-, mitochondria-, and caspase-associated proteins than that of IRI or PEITC treatment only in HCT 116 cells. Based on these observations, PEITC potentiates IRI anticancer activity by promoting cell apoptosis in the human colon HCT 116 cells. Thus, PEITC may be a potential enhancer for IRI in humans as an anticolon cancer drug in the future.

PW06 suppresses cancer cell metastasis in human pancreatic carcinoma MIA PaCa-2 cells via the inhibitions of p-Akt/mTOR/NF-κB and MMP2/MMP9 signaling pathways in vitro.

PW06 [(E)-3-(9-ethyl-9H-carbazol-3-yl)-1-(2,5-dimethoxyphenyl) prop-2-en-1-one], a kind of the carbazole derivative containing chalcone moiety, induced cell apoptosis in human pancreatic carcinoma in vitro. There is no investigation to show that PW06 inhibits cancer cell metastasis in human pancreatic carcinoma in vitro. Herein, PW06 (0.1-0.8 µM) significantly exists in the antimetastatic activities of human pancreatic carcinoma MIA PaCa-2 cells in vitro. Wound healing assay shows PW06 at 0.2 µM suppressed cell mobility by 7.45 and 16.55% at 6 and 24 hours of treatments. PW06 at 0.1 and 0.2 µM reduced cell mobility by 14.72 and 21.8% for 48 hours of treatment. Transwell chamber assay indicated PW06 (0.1-0.2 µM) suppressed the cell migration (decreased 26.67-35.42%) and invasion (decreased 48.51-68.66%). Atomic force microscopy assay shows PW06 (0.2 µM) significantly changed the shape of cell morphology. The gelatin zymography assay indicates PW06 decreased MMP2's and MMP9's activities at 48 hours of treatment. Western blotting assay further confirms PW06 reduced levels of MMP2 and MMP9 and increased protein expressions of EGFR, SOS1, and Ras. PW06 also increased the p-JNK, p-ERK, and p-p38. PW06 increased the expression of PI3K, PTEN, Akt, GSK3α/ß, and E-cadherin. Nevertheless, results also show PW06 decreased p-Akt, mTOR, NF-κB, p-GSK3ß, ß-catenin, Snail, N-cadherin, and vimentin in MIA PaCa-2 cells. The confocal laser microscopy examination shows PW06 increased E-cadherin but decreased vimentin in MIA PaCa-2 cells. Together, our findings strongly suggest that PW06 inhibited the p-Akt/mTOR/NF-κB/MMPs pathways, increased E-cadherin, and decreased N-cadherin/vimentin, suppressing the migration and invasion in MIA PaCa-2 cells in vitro.

Resveratrol Analog 4-Bromo-Resveratrol Inhibits Gastric Cancer Stemness through the SIRT3-c-Jun N-Terminal Kinase Signaling Pathway.

Chemotherapy is the treatment of choice for gastric cancer, but the currently available therapeutic drugs have limited efficacy. Studies have suggested that gastric cancer stem cells may play a key role in drug resistance in chemotherapy. Therefore, new agents that selectively target gastric cancer stem cells in gastric tumors are urgently required. Sirtuin-3 (SIRT3) is a deacetylase that regulates mitochondrial metabolic homeostasis to maintain stemness in glioma stem cells. Targeting the mitochondrial protein SIRT3 may provide a novel therapeutic option for gastric cancer treatment. However, the mechanism by which stemness is regulated through SIRT3 inhibition in gastric cancer remains unknown. We evaluated the stemness inhibition ability of the SIRT3 inhibitor 4'-bromo-resveratrol (4-BR), an analog of resveratrol in human gastric cancer cells. Our results suggested that 4-BR inhibited gastric cancer cell stemness through the SIRT3-c-Jun N-terminal kinase pathway and may aid in gastric cancer stem-cell-targeted therapy.

Genistein enhances the effects of L-asparaginase on inducing cell apoptosis in human leukemia cancer HL-60 cells.

Genistein (GEN) has been shown to induce apoptotic cell death in various human cancer cells. L-asparaginase (Asp), a clinical drug for leukemia, has been shown to induce cell apoptosis in leukemia cells. No available information concerning GEN combined with Asp increased the cell apoptosis compared to GEN or Asp treatment alone. The objective of this study is to evaluate the anti-leukemia activity of GEN combined with Asp on human leukemia HL-60 cells in vitro. The cell viability, the distribution of cell cycle, apoptotic cell death, and the level of ΔΨm were examined by flow cytometric assay. The expressions of apoptosis-associated proteins were measured by western blotting. GEN combined with Asp revealed a more significant decrease in total viable cells and induced a higher percentage of G2/M phase arrest, DNA damage, and cell apoptosis than that of GEN or Asp treatment only in HL-60 cells. Furthermore, the combined treatments (GEN and Asp) showed a higher decrease in the level of ΔΨm than that of GEN or Asp treatment only. These results indicated that GEN combined with Asp induced mitochondria dysfunction by disrupting the mitochondrial membrane potential. The results from western blotting demonstrated that the treatment of GEN combined with Asp showed a higher increase in the levels of Bax and Bak (pro-apoptotic proteins) and an active form of caspase-3 and a higher decrease in Bcl-2 (anti-apoptotic protein) than that of GEN or Asp treatment alone. GEN significantly enhances the efficiency of Asp on cytotoxic effects (the induction of apoptosis) in HL-60 cells.

Demethoxycurcumin Suppresses Human Brain Glioblastoma Multiforme GBM 8401 Cell Xenograft Tumor in Nude Mice In Vivo.

Demethoxycurcumin (DMC), a derivate of curcumin, has been shown to induce apoptotic cell death in human glioblastoma multiforme GBM 8401 cells via cell cycle arrest and induction of cell apoptosis. However, there is no report showing DMC suppresses glioblastoma multiforme cells in vivo. In the present study, we investigated the effects of DMC on GBM8401 cells in vivo. At first, we established a luciferase-expressing stable clone named GBM 8401/luc2. Second, mice were inoculated subcutaneously with GBM 8401/luc2 cells to generate a xenograft tumor mice model. After inoculation, tumor volume reached 100-120 mm3, and all mice were randomly divided into three groups: Group I was treated with 110 µL phosphate-buffered solution (PBS) containing 0.1% dimethyl sulfoxide, Group II with 30 mg/kg of DMC, and Group III with 60 mg/kg of DMC. Mice from each group were given the oral treatment of DMC by gavage for 21 days. The body weight and tumor volume were recorded every 3 days. DMC significantly decreased the tumor volumes, and 60 mg/kg treatment showed a higher decrease in tumor volumes than that of 30 mg/kg, However, DMC did not affect the body weights. The photons emitted from mice tumors were detected with Xenogen IVIS imaging system, DMC at both doses decreased the total photon flux and 60 mg/kg treatment of DMC has low total photon flux than that of 30 mg/kg. The tumor volumes and weights in 60 mg/kg treatment of DMC were lower than that of 30 mg/kg. Immunohistochemical analysis was used to measure protein expression of tumors and results showed that DMC treatment led to lightly staining with anti-Bcl-2 and -XIAP and 60 mg/kg treatment of DMC has lighter staining with anti-Bcl-2 and -XIAP than that of 30 mg/kg. The higher dose (60 mg/kg) of DMC has higher signals of cleaved-caspase-3 than that of the lower dose (30 mg/kg). Furthermore, the hematoxylin and eosin (H&E) staining of liver tissues showed no significant difference between DMC-treated and control-groups. Overall, these observations showed that DMC suppressed tumor properties in vivo and DMC may be used against human glioblastoma multiforme in the future.

Tetrandrine Suppresses Human Brain Glioblastoma GBM 8401/luc2 Cell-Xenografted Subcutaneous Tumors in Nude Mice In Vivo.

Tetrandrine (TET), a bisbenzylisoquinoline (BBI) alkaloid, is isolated from the plant Stephania tetrandra S. Moore and has a wide range of biological activity, including anticancer properties in vitro and in vivo. At first, we established a luciferase-expressing stable clone that was named GBM 8401/luc2 cells. Herein, the primary results indicated that TET reduced the total cell viability and induced cell apoptosis in GBM 8401/luc2 human glioblastoma cells. However, there is no available information showing that TET suppresses glioblastoma cells in vivo. Thus, we investigated the effects and mechanisms of TET on a GBM 8401/luc2 cell-generated tumor in vivo. After the tumor volume reached 100-120 mm3 in subcutaneously xenografted nude mice, all of the mice were randomly divided into three groups: Group I was treated with phosphate-buffered solution (PBS) containing 0.1% dimethyl sulfoxide, Group II with 25 mg/kg of TET, and Group III with 50 mg/kg of TET. All mice were given the oral treatment of PBS or TET by gavage for 21 days, and the body weight and tumor volumes were recorded every 5 days. After treatment, individual tumors, kidneys, livers, and spleens were isolated from each group. The results showed that TET did not affect the body weights, but it significantly decreased the tumor volumes. The TET treatment at 50 mg/kg had a two-fold decrease in tumor volumes than that at 25 mg/kg when compared to the control. TET decreased the total photon flux, and treatment with TET at 50 mg/kg had a lower total photon flux than that at 25 mg/kg, as measured by a Xenogen IVIS imaging system. Moreover, the higher TET treatment had lower tumor volumes and weights than those of the lower dose. The apoptosis-associated protein expression in the tumor section was examined by immunohistochemical analysis, and the results showed that TET treatment reduced the levels of c-FLIP, MCL-1, and XIAP but increased the signals of cleaved-caspase-3, -8, and -9. Furthermore, the hematoxylin and eosin (H & E) staining of kidney, liver, and spleen tissues showed no significant difference between the TET-treated and control groups. Overall, these observations demonstrated that TET suppressed subcutaneous tumor growth in a nude-mice model via the induction of cell apoptosis.

Genistein induces apoptosis in vitro and has antitumor activity against human leukemia HL-60 cancer cell xenograft growth in vivo.

Genistein, a major isoflavone compound in soybeans, has been shown to have biological activities including anti-cancer activates. In the present, we investigated the anti-leukemia activity of genistein on HL-60 cells in vitro. The percentage of viable cell, cell cycle distribution, apoptotic cell death, reactive oxygen species (ROS), and Ca2+ production and the level of ΔΨm were measured by flow cytometric assay. Cell apoptosis and endoplasmic reticulum (ER) stress associated protein expressions were examined by Western blotting assay. Calpain 1, GRP78, and GADD153 expression were measured by confocal laser microscopy. Results indicated that genistein-induced cell morphological changes, decreased the total viable cells, induced G2 /M phase arrest and DNA damage and fragmentation (cell apoptosis) in HL-60 cells. Genistein promoted ROS and Ca2+ productions and decreased the level of ΔΨm in HL-60 cells. Western blotting assay demonstrated that genistein increased ER stress-associated protein expression such as IRE-1α, Calpain 1, GRP78, GADD153, caspase-7, caspase-4, and ATF-6α at 20-50 µM treatment and increased apoptosis associated protein expression such as pro-apoptotic protein Bax, PARP-cleavage, caspase-9, and -3, but decreased anti-apoptotic protein such as Bcl-2 and Bid in HL-60 cells. Calpain 1, GRP78, and GADD153 were increased in HL-60 cells after exposure to 40 µM of genistein. In animal xenografted model, mice were intraperitoneally injected with genistein (0, 0.2, and 0.4 mg/kg) for 28 days and the body weight and tumor volume were recorded. Results showed that genistein did not affect the body weights but significantly reduced the tumor weight in 0.4 mg/kg genistein-treated group. Genistein also increased the expressions of ATF-6α, GRP78, Bax, Bad, and Bak in tumor. In conclusion, genistein decreased cell number through G2 /M phase arrest and the induction of cell apoptosis through ER stress- and mitochondria-dependent pathways in HL-60 cells and suppressed tumor properties in vivo.

Benzyl isothiocyanate inhibits human brain glioblastoma multiforme GBM 8401 cell xenograft tumor in nude mice in vivo.

Benzyl isothiocyanate (BITC), a member of isothiocyanates (ITCs), has been shown to induce cell death in many human cancer cells, but there is no further report to show BITC suppresses glioblastoma multiforme cells in vivo. In the present study, we investigate the effects of BITC on the inhibition of GBM 8401/luc2 cell generated tumor on athymic nude mice. We established a luciferase expressing stable clone named as GBM 8401/luc2. Thirty male mice were inoculated subcutaneously with GBM 8401/luc2 cells to generate xenograft tumor mice model. Group I was treated with 110 µL phosphate-buffered solution plus 10 µL dimethyl sulfoxide, Group II-III with BITC (5 or 10 µmol/100 µL/day, relatively). Mice were given oral treatment of BITC by gavage for 21 days. Results showed that BITC did not affect the body weights. After anesthetized, the photons emitted from mice tumor were detected with Xenogen IVIS imaging system 200 and higher dose of BITC have low total photon flux than that of lower dose of BITC. Results also showed that higher dose of BITC have low total tumor volumes and weights than that of low dose of BITC. Isolated tumors were investigated by immunohistochemical analysis and results showed that BITC at both dose of treatment weakly stained with anti-MCL1 and -XIAP. However, both dose of BITC treatments have strong signals of caspase-3 and Bax. Overall, these data demonstrated that BITC suppressed tumor properties in vivo. Overall, based on these observations, BITC can be used against human glioblastoma multiforme in the future.

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.

Alpha-phellandrene-induced apoptosis in mice leukemia WEHI-3 cells in vitro.

Although reports have shown that α-phellandrene (α-PA) is one of the monoterpenes and is often used in the food and perfume industry, our previous studies have indicated that α-PA promoted immune responses in normal mice in vivo. However, there is no available information to show that α-PA induced cell apoptosis in cancer cells, thus, we investigated the effects of α-PA on the cell morphology, viability, cell cycle distribution, and apoptosis in mice leukemia WEHI-3 cells in vitro. Results indicated that α-PA induced cell morphological changes and decreased viability, induced G0/G1 arrest and sub-G1 phase (apoptosis) in WEHI-3 cells. α-PA increased the productions of reactive oxygen species (ROS) and Ca2+ and decreased the levels of mitochondrial membrane potential (ΔΨm ) in dose- and time-dependent manners in WEHI-3 cells that were analyzed by flow cytometer. Results from confocal laser microscopic system examinations show that α-PA promoted the release of cytochrome c, AIF, and Endo G from mitochondria in WEHI-3 cells. These results are the first findings to provide new information for understanding the mechanisms by which α-PA induces cell cycle arrest and apoptosis in WEHI-3 cells in vitro. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1640-1651, 2016.

Tetrandrine Induces Apoptosis of Human Nasopharyngeal Carcinoma NPC-TW 076 Cells through Reactive Oxygen Species Accompanied by an Endoplasmic Reticulum Stress Signaling Pathway.

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy of the head and neck and the incidence is higher in Southeast Asia. Tetrandrine (TET) is a bisbenzylisoquinoline alkaloid, a natural product, and exhibits biological activities including action against many human cancer cell lines. However, the molecular mechanism of TET-induced cell apoptosis in human NPC cells is still unclear. In the present study, we investigated TET-induced apoptotic cell death and associated possible signal pathways on human nasopharyngeal carcinoma NPC-TW 076 cells in vitro. Phase contrast microscopy was used to examine cell morphology and DAPI staining was used to examine chromatin condensation. Flow cytometry assay was used to measure total viable cells, cell cycle and sub-G1 phase distribution, reactive oxygen species (ROS), Ca2+, and mitochondria membrane potential (ΔΨm) in NPC-TW 076 cells. Results indicate that TET induced cell death through the cell morphological changes, caused G0/G1 phase arrest, increased ROS and Ca2+ production, and finally caused apoptotic cell death in NPC-TW 076 cells. There was no influence on the level of ΔΨm after TET treatment. Western blotting indicated that TET increased endoplasmic reticulum (ER) stress associated protein expression such as GADD153, GRP78, ATF-6α and ATF-6 ßwhich indicated that TET induced cell death through ER stress. ER stress is a potential target in cancer treatment, so the ability of TET to induce ER stress response and to activate programming cell death in NPC-TW 076 cells make this molecule become a promising anticancer agent.

Alpha-phellandrene-induced DNA damage and affect DNA repair protein expression in WEHI-3 murine leukemia cells in vitro.

Although there are few reports regarding α-phellandrene (α-PA), a natural compound from Schinus molle L. essential oil, there is no report to show that α-PA induced DNA damage and affected DNA repair associated protein expression. Herein, we investigated the effects of α-PA on DNA damage and repair associated protein expression in murine leukemia cells. Flow cytometric assay was used to measure the effects of α-PA on total cell viability and the results indicated that α-PA induced cell death. Comet assay and 4,6-diamidino-2-phenylindole dihydrochloride staining were used for measuring DNA damage and condensation, respectively, and the results indicated that α-PA induced DNA damage and condensation in a concentration-dependent manner. DNA gel electrophoresis was used to examine the DNA damage and the results showed that α-PA induced DNA damage in WEHI-3 cells. Western blotting assay was used to measure the changes of DNA damage and repair associated protein expression and the results indicated that α-PA increased p-p53, p-H2A.X, 14-3-3-σ, and MDC1 protein expression but inhibited the protein of p53, MGMT, DNA-PK, and BRCA-1.

Crude extract of Rheum palmatum L inhibits migration and invasion of LS1034 human colon cancer cells acts through the inhibition of matrix metalloproteinase-2/-9 by MAPK signaling.

Crude extract of Rheum palmatum L. (CERP) has been used to treat different diseases in the Chinese population for decades. In this study, we investigated the anti-metastasis effects of CERP on LS1034 human colorectal cancer cells in vitro and examined potential mechanisms of its effects. CERP significantly inhibited cell migration and invasion of LS1034 cells. We also found that CERP inhibited protein levels of matrix metalloproteinases-2 (MMP-2) and matrix metalloproteinases-9 (MMP-9), and cytosolic NF-kB p65, RHO A, ROCK 1. Furthermore, we found CERP inhibited protein levels of GRB2, SOS1, MKK7, FAK, Rho A, ROCK 1, VEGF, PKC, AKT, phosphor-AKT (Thr308), Cyclin D, iNOS, COX2, NF-kB p65, p-ERK1/2, p-JNK1/2, p-p38, p-c-jun, MMP-2, MMP-9, MMP-1, MMP-7, MMP-10, UPA and increased the protein level of Ras in LS1034 cells. In conclusion, our results suggest that CERP may be used as a novel anti-metastasis agent for the treatment of human colon cancer cells.

Crude extract of Rheum palmatum L induced cell death in LS1034 human colon cancer cells acts through the caspase-dependent and -independent pathways.

Crude extract of Rheum palmatum L (CERP) has been used to treat different diseases in the Chinese population for decades. In this study, we investigated the effects of CERP on LS1034 human colorectal cancer cells in vitro and also examined possible mechanisms of cell death. Flow cytometric assays were used to measure the percentage of viable cells, cell cycle distribution including the sub-G1 phase (apoptosis), the activities of caspase-8, -9, and -3, reactive oxygen species (ROS) and Ca(2+) levels, and mitochondrial membrane potential (ΔΨm). DNA damage, nuclei condensation, protein expression, and translocation were examined by Comet assay, 4'-6-diamidino-2-phenylindole (DAPI) staining, Western blotting, and confocal laser system microscope, respectively. CERP induced apoptosis as seen by DNA fragmentation and DAPI staining in a concentration- and time-dependent manner in cancer cells. CERP was associated with an increase in the Bax/Bcl-2 protein ratio and CERP promoted the activities of caspase-8, -9, and -3. Both ROS and Ca(2+) levels were increased by CERP but the compound decreased levels of ΔΨm in LS1034 cells. Laser confocal microscope also confirmed that CERP promoted the expressions of AIF, Endo G, cytochrome c, and GADD153 to induce apoptosis through mitochondrial-dependent pathway.

PW06 Triggered Fas-FADD to Induce Apoptotic Cell Death In Human Pancreatic Carcinoma MIA PaCa-2 Cells through the Activation of the Caspase-Mediated Pathway.

Pancreatic cancer has higher incidence and mortality rates worldwide. PW06 [(E)-3-(9-ethyl-9H-carbazol-3-yl)-1-(2,5-dimethoxyphenyl) prop-2-en-1-one] is a carbazole derivative containing chalcone moiety which was designed for inhibiting tumorigenesis in human pancreatic cancer. This study is aimed at investigating PW06-induced anticancer effects in human pancreatic cancer MIA PaCa-2 cells in vitro. The results showed PW06 potent antiproliferative/cytotoxic activities and induced cell morphological changes in a human pancreatic cancer cell line (MIA PaCa-2), and these effects are concentration-dependent (IC50 is 0.43 µM). Annexin V and DAPI staining assays indicated that PW06 induced apoptotic cell death and DNA condensation. Western blotting indicated that PW06 increased the proapoptotic proteins such as Bak and Bad but decreased the antiapoptotic protein such as Bcl-2 and Bcl-xL. Moreover, PW06 increased the active form of caspase-8, caspase-9, and caspase-3, PARP, releasing cytochrome c, AIF, and Endo G from mitochondria in MIA PaCa-2 cells. Confocal laser microscopy assay also confirmed that PW06 increased Bak and decreased Bcl-xL. Also, the cells were pretreated with inhibitors of caspase-3, caspase-8, and caspase-9 and then were treated with PW06, resulting in increased viable cell number compared to PW06 treated only. Furthermore, PW06 showed a potent binding ability with hydrophobic interactions in the core site of the Fas-Fas death domains (FADD). In conclusion, PW06 can potent binding ability to the Fas-FADD which led to antiproliferative, cytotoxic activities, and apoptosis induction accompanied by the caspase-dependent and mitochondria-dependent pathways in human pancreatic cancer MIA PaCa-2 cells.

Combination Treatment of Sorafenib and Bufalin Induces Apoptosis in NCI-H292 Human Lung Cancer Cells In Vitro.

BACKGROUND/AIM: Lung cancer notably contributes to tumor-associated mortality worldwide, and standard chemotherapy is used for lung cancer patients. However, its therapeutic efficacy remains unsatisfactory. This study aimed to evaluate the effects and molecular mechanisms of sorafenib and bufalin combination therapy on lung cancer cells in vitro. MATERIALS AND METHODS: NCI-H292 cells were treated with sorafenib, bufalin, and sorafenib in combination with bufalin. Cell viability, ROS production, Ca2+ release, and mitochondrial membrane potential were examined by flow cytometric assay. Annexin V/PI staining and chromatin condensation were examined by the apoptosis assays. Finally the molecular mechanism of apoptosis-associated protein expression was investigated by western blotting. RESULTS: NCI-H292 cells treated with sorafenib in combination with bufalin showed significantly decreased viability, enhanced cellular apoptosis, and DNA condensation when compared to that with sorafenib or bufalin alone. Moreover, the combination treatment exhibited higher reactive oxygen species (ROS) production and lower mitochondrial membrane potential (ΔΨm). The combined treatment resulted in higher expression of SOD but lower catalase compared to sorafenib treatment alone. Compared to sorafenib or bufalin treatment alone, the combination treatment resulted in lower Bcl-2 expression but higher Bax, Bad, APAF-1, caspase-3, and caspase-9. CONCLUSION: Sorafenib in combination with bufalin shows more potent cytotoxic effects and cell apoptosis than sorafenib or bufalin treatment alone in NCI-H292 cells. The combined treatment significantly enhanced apoptotic cell death in NCI-H292 lung cancer cells by activating ROS-, mitochondria-, and caspase-signaling pathways in vitro.

Bisdemethoxycurcumin suppresses human osteosarcoma U­2 OS cell migration and invasion via affecting the PI3K/Akt/NF­κB, PI3K/Akt/GSK3ß and MAPK signaling pathways in vitro.

The metastasis of human osteosarcoma (OS) shows a difficult­to­treat clinical scenario and results in decreased quality of life and diminished survival rates. Finding or developing novel treatments to improve the life quality of patients is urgent. Bisdemethoxycurcumin (BDMC), a natural product, was obtained from the rhizome of turmeric (Curcuma longa) and exerts antitumor activities in numerous human cancer cell lines. At present, there is no study showing BDMC effects on OS cell migration and invasion. In the present study, the effects of BDMC on cell migration and invasion of OS U­2 OS cells were investigated in vitro. Cell viability and proliferation were measured by flow cytometric and MTT assays, respectively. Cell motility, MMP­2 and ­9 activity, and cell migration and invasion were assayed by scratch wound healing, gelatin zymography, and Transwell chamber assays, respectively. The protein expression levels were measured by western blotting. BDMC at 20 and 40 µM significantly reduced total cell viability, and BDMC at 5 and 10 µM significantly inhibited cell motility in U­2 OS cells. BDMC significantly suppressed the activities of MMP­2 and MMP­9 in U­2 OS cells. BDMC suppressed cell invasion and migration after 24 h treatment in U­2 OS cells, and these effects were in a dose­dependently manner. Results from western blotting indicated that BDMC significantly decreased the protein expression levels of PI3K/Akt/NF­κB, PI3K/Akt/GSK3ß, and MAPK pathway in U­2 OS cells. Furthermore, BDMC inhibited uPA, MMP­2, MMP­9, MMP­13, N­cadherin, VE­cadherin, and vimentin but increased E­cadherin in U­2 OS cells. Based on these observations, it was suggested that BDMC may be a potential candidate against migration and invasion of human OS cells in the future.

Ouabain Suppresses Cell Migration and Invasion in Human Gastric Cancer AGS Cells Through the Inhibition of MMP Signaling Pathways.

BACKGROUND/AIM: Ouabain has been shown to induce human cancer cell death via apoptosis. Still, its anti-metastatic effect on cell migration and invasion of human gastric cancer cells has not been addressed. MATERIALS AND METHODS: Cell proliferation and viability were measured by the MTT assay and flow cytometry, respectively. Cell motitlity was analysed by wound healing assay. Cell migration and invasion were analysed by the transwell system. Protein expression was assayed by western blotting. RESULTS: Ouabain decreased AGS cell proliferation, cell viability, and motility. In addition, ouabain inhibited AGS cell migration and invasion. Furthermore, ouabain decreased matrix metalloproteinase-2 (MMP-2) activity at 48 h. Ouabain reduced the levels of proteins associated with PI3K/AKT and p38/MAPK pathways. In addition, ouabain decreased the expressions of N-cadherin, tissue inhibitor of metalloproteinases-1 (TIMP-1), urokinase-type plasminogen activator (c-uPA), and MMP-2 at 48 h. CONCLUSION: Ouabain suppresses cell metastasis through multiple signaling pathways in AGS cells.

Danthron induced apoptosis through mitochondria- and caspase-3-dependent pathways in human brain glioblastoma multiforms GBM 8401 cells.

Danthron (1,8-dihydroxyanthraquinone), is one of component from Rheum palmatum L. (Polygonaceae), has been shown several biological activities but did not show to induce apoptosis in human brain tumor cells. The aim of this study is to investigate the mechanisms by danthron for the induction of apoptotic potential on human brain glioblastoma multiforms GBM 8401 cell line. Danthron showed a marked concentration- and time-dependent inhibition of GBM 8401 cell viability and induced apoptosis in a dose-and time-dependent manner. There was an attenuation of mitochondrial membrane potential (DeltaPsi(m)) with the alterations of Bcl-2/Bax protein ratio in GBM 8401 cells, indicating the participation of a mitochondria-related mechanism. Pretreatment of a caspase-8 inhibitor (Z-IETD-FMK), caspase-9 inhibitor (Z-LEHD-FMK) and caspase-3 inhibitor (Z-DEVE-FMK) significantly increased the viable of GBM 8401 cells implied that the participations of caspases. Western blotting analysis also showed the activation of initiator caspase-8 and caspase-9, and executor caspase-3 in GBM 8401 cells. Meanwhile, danthron also promoted the generation of reactive oxygen species (ROS) and cytosolic Ca(2+) in GBM 8401 cells. Taken together, our data showed that danthron induced apoptosis in GBM 8401 cells through mitochondria-related and caspase-related pathways, and it may be further evaluated as a chemotherapeutic agent for human brain cancer.

Gypenosides causes DNA damage and inhibits expression of DNA repair genes of human oral cancer SAS cells.

Gypenosides (Gyp) are the major components of Gynostemma pentaphyllum Makino, a Chinese medical plant. Recently, Gyp has been shown to induce cell cycle arrest and apoptosis in many human cancer cell lines. However, there is no available information to address the effects of Gyp on DNA damage and DNA repair-associated gene expression in human oral cancer cells. Therefore, we investigated whether Gyp induced DNA damage and DNA repair gene expression in human oral cancer SAS cells. The results from flow cytometric assay indicated that Gyp-induced cytotoxic effects led to a decrease in the percentage of viable SAS cells. The results from comet assay revealed that the incubation of SAS cells with Gyp led to a longer DNA migration smear (comet tail) when compared with control and this effect was dose-dependent. The results from real-time PCR analysis indicated that treatment of SAS cells with 180 mug/ml of Gyp for 24 h led to a decrease in 14-3-3sigma, DNA-dependent serine/threonine protein kinase (DNAPK), p53, ataxia telangiectasia mutated (ATM), ataxia-telangiectasia and Rad3-related (ATR) and breast cancer gene 1 (BRCA1) mRNA expression. These observations may explain the cell death caused by Gyp in SAS cells. Taken together, Gyp induced DNA damage and inhibited DNA repair-associated gene expressions in human oral cancer SAS cells in vitro.