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.

The combination of Raman Spectroscopy and Mass Spectrometry to investigate cutaneous metallosis

Skin is uniquely accessible to investigation by modern scientific methods. Raman spectroscopy is a non-invasive technology for in-vivo analysis of molecular composition. Furthermore, a skin biopsy examined with Laser ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) provides high resolution multi-element mapping with high sensitivity and precision for exogenous metals in biological tissue which have no intrinsic abundance. This technique has been successfully applied to identify a variety of metals including gadolinium in cerebral vessel walls after contrast studies (1) . These two techniques were used to investigate metallosis from a shoulder joint replacement.

Melittin suppresses epithelial-mesenchymal transition and metastasis in human gastric cancer AGS cells via regulating Wnt/BMP associated pathway

Gastric cancer has a poor prognosis; once cancer has metastasized, it can easily lead to patient death. Melittin is one of the major components extracted from the bee venom. It has been shown that melittin emerges antitumor activities against many human cancer cell lines. Our results indicated that melittin at 0.2-0.5 µm significantly reduced total cell viability in human gastric cancer AGS cells. At low concentrations (0.05-0.15 µm), melittin displayed antimetastasis effects and inhibited cell adhesion and colony formation. Besides, it inhibited cell motility and suppressed cell migration and invasion. Melittin inhibited the activities of MMP-2 and MMP-9 and the integrity of cell membrane in AGS cells. Furthermore, Western blotting results showed that melittin decreased the protein expressions of Wnt/BMP and MMP-2 signaling pathways. Based on these observations, melittin inhibited cell migration and invasion of AGS cells through multiple signaling pathways. It may be used to treat metastasized gastric cancers in the future.

Lenvatinib Induces AKT/NF-κB Inactivation, Apoptosis Signal Transduction and Growth Inhibition of Non-small Cell Lung Cancer In Vivo

BACKGROUND/AIM

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with poor prognosis. Lenvatinib is a multi-kinase inhibitor that has the potential to suppress tumor progression. Our previous study suggested that lenvatinib induces cytotoxicity and apoptosis in CL-1-5-F4 cells in vitro. However, whether lenvatinib suppresses NSCLC progression in vivo remains unclear.

MATERIALS AND METHODS

Tumor growth inhibition and normal tissue toxicity evaluation following lenvatinib treatment were performed on CL-1-5-F4-bearing mice.

RESULTS

Tumor growth calculated by caliper and living cell intensity decreased by lenvatinib treatment as analysed by bioluminescence imaging. Phosphorylation of AKT, NF-κB, and NF-κB downstream proteins involved in tumor progression were reduced by lenvatinib in the tumor tissue. No pathological changes were found in the liver, kidney, and spleen after lenvatinib treatment.

CONCLUSION

Induction of apoptosis and suppression of AKT/NF-κB were associated with lenvatinib-induced inhibition of the progression of NSCLC in vivo.

ERK/AKT Inactivation and Apoptosis Induction Associate With Quetiapine-inhibited Cell Survival and Invasion in Hepatocellular Carcinoma Cells

BACKGROUND/AIM

Quetiapine, an atypical antipsychotic, has been encountered as a potential protective agent to suppress various types of tumor growth. However, the inhibitory mechanism of quetiapine in hepatocellular carcinoma (HCC) still remains unclear. The purpose of present study was to investigate the inhibitory mechanism of quetiapine on cell survival and invasion in HCC.

MATERIALS AND METHODS

Changes of apoptotic signaling, migration/invasion ability, and signaling transduction involved in cell survival and invasion were evaluated with flow cytometry, migration/invasion, and western blot assays.

RESULTS

Quetiapine inhibited cell proliferation and migration/invasion in SK-Hep1 and Hep3B cells. Quetiapine induced extrinsic and intrinsic apoptotic pathways. Activation of extracellular signal-regulated kinases (ERK), protein kinase B (AKT), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB), expression of anti-apoptotic, and metastasis-associated proteins were decreased by quetiapine.

CONCLUSION

The apoptosis induction, the decreased expression of ERK/AKT-mediated anti-apoptotic and the metastasis-associated proteins were associated with quetiapine-inhibited cell survival and invasion in HCC in vitro.

Therapeutic Efficacy and Inhibitory Mechanism of Regorafenib Combined With Radiation in Colorectal Cancer

BACKGROUND

Although both chemotherapy and radiotherapy (RT) can sufficiently maintain tumor suppression of colorectal cancer (CRC), these treatments may trigger the expression of nuclear factor kappa B (NF-κB) and compromise patients' survival. Regorafenib suppresses NF-κB activity in various tumor types. However, whether regorafenib may act as a suitable radiosensitizer to enhance therapeutic efficacy of RT remains unknown.

MATERIALS AND METHODS

Here, we established a CRC-bearing animal model to investigate the therapeutic efficacy of regorafenib in combination with RT, through measurement of tumor growth, body weight, whole-body computed tomography (CT) scan and immunohisto-chemistry staining.

RESULTS

Smallest tumor size and weight were found in the combination treatment group. In addition, RT-induced up-regulation of NF-κB and downstream proteins were diminished by regorafenib. Moreover, the body weight and liver pathology in the treated group were similar to those of the non-treated control group.

CONCLUSION

Regorafenib may enhance the anti-CRC efficacy of RT.

The In Vivo Radiosensitizing Effect of Magnolol on Tumor Growth of Hepatocellular Carcinoma

BACKGROUND/AIM

Radiation (RT) induced ERK/NF-κB in hepatocellular carcinoma (HCC) has been reported in our previous works; it weakens the toxicity of RT or triggers a radioresistance effect. Thus, combining RT with a suitable NF-κB inhibitor may sensitize HCC to RT. Magnolol, a bioactive compound, was known to have anti-inflammatory and anti-tumor functions. Here, we aimed to investigate whether magnolol may enhance anti-HCC efficacy of RT in vivo.

MATERIALS AND METHODS

We established a Hep3B bearing mouse to evaluate the efficacy of the combination treatment of magnolol and RT.

RESULTS

Most significantly, tumor volume and tumor weight inhibition was found in the combination group. Tumor immunohistochemistry staining also illustrated the suppression of RT-induced ERK/NF-κB-related proteins expression by magnolol. In addition, intrinsic apoptosis-related proteins, such as caspase-3 and -9, were markedly increased in the combination group.

CONCLUSION

Magnolol may effectively enhance anti-HCC ability of RT by downregulating the expression of ERK/NF-κB-related proteins and increasing the expression of apoptosis-related proteins.

Anti-metastatic Effects of Cationic KT2 Peptide (a Lysine/Tryptophan-rich Peptide) on Human Melanoma A375.S2 Cells

BACKGROUND/AIM

KT2 is a lysine/tryptophan-rich peptide modified from Crocodylus siamensis Leucrocin I. In this study, we examined the cell toxicity, cellular uptake, anti-migration and anti-invasion activities of KT2 in A375.S2 human melanoma cells.

MATERIALS AND METHODS

A375.S2 cells were treated with KT2 peptide and then we performed MTT assay, study of cellular uptake by a confocal microscope, wound healing assay, transwell migration/invasion assay, and evaluation of the expression of metastasis-associated proteins.

RESULTS

KT2 can be internalized through the plasma membrane and can slightly alter cell morphology, decrease the percentage of viable cells and inhibit cell migration and invasion of A375.S2 cells in a dose-dependent manner. This peptide suppressed MMP-2 activity, as measured by gelatine zymography assay. The protein level of MMP-2 was decreased by KT2. KT2 also down-regulated metastasis pathway-related molecules, including FAK, RhoA, ROCK1, GRB2, SOS-1, p-JNK, p-c-Jun, PI3K, p-AKT (Thr308), p-AKT (Ser473), p-p38, MMP-9, NF-kB, and uPA.

CONCLUSION

These results indicate that KT2 inhibits the migration and invasion of human melanoma cells by decreasing MMP-2 and MMP-9 expression through inhibition of FAK, uPA, MAPK, PI3K/AKT NF-kB, and RhoA-ROCK signalling pathways. These findings suggest that KT2 deserves further investigation as an anti-metastatic agent for human melanoma.

Ergosta-7, 9 (11), 22-trien-3β-ol Interferes with LPS Docking to LBP, CD14, and TLR4/MD-2 Co-Receptors to Attenuate the NF-κB Inflammatory Pathway In Vitro and Drosophila

Ergosta-7, 9 (11), 22-trien-3β-ol (EK100) was isolated from Cordyceps militaris, which has been used as a traditional anti-inflammatory medicine. EK100 has been reported to attenuate inflammatory diseases, but its anti-inflammatory mechanism is still unclear. We were the first to investigate the effect of EK100 on the Toll-like receptor 4 (TLR4)/nuclear factor of the κ light chain enhancer of B cells (NF-κB) signaling in the lipopolysaccharide (LPS)-stimulated RAW264.7 cells and the green fluorescent protein (GFP)-labeled NF-κB reporter gene of Drosophila. EK100 suppressed the release of the cytokine and attenuated the mRNA and protein expression of pro-inflammatory mediators. EK100 inhibited the inhibitor kappa B (IκB)/NF-κB signaling pathway. EK100 also inhibited phosphatidylinositol-3-kinase (PI3K)/Protein kinase B (Akt) signal transduction. Moreover, EK100 interfered with LPS docking to the LPS-binding protein (LBP), transferred to the cluster of differentiation 14 (CD14), and bonded to TLR4/myeloid differentiation-2 (MD-2) co-receptors. Compared with the TLR4 antagonist, resatorvid (CLI-095), and dexamethasone (Dexa), EK100 suppressed the TLR4/AKT signaling pathway. In addition, we also confirmed that EK100 attenuated the GFP-labeled NF-κB reporter gene expression in Drosophila. In summary, EK100 might alter LPS docking to LBP, CD14, and TLR4/MD-2 co-receptors, and then it suppresses the TLR4/NF-κB inflammatory pathway in LPS-stimulated RAW264.7 cells and Drosophila.

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 ΔΨ_m 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 ΔΨ_m 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 Proliferation, Migration, and Invasion of Human Brain Glioblastoma Multiforme GBM 8401 Cells via PI3K/Akt Pathway

BACKGROUND/AIM

Demethoxycurcumin (DMC), one of the derivatives of curcumin, has been shown to induce apoptotic cell death in many human cancer cell lines. However, there is no available information on whether DMC inhibits metastatic activity in human glioblastoma cancer cells in vitro.

MATERIALS AND METHODS

DMC at 1.0-3.0 μM significantly decreased the proliferation of GBM 8401 cells; thus, we used 2.0 μM for further investigation regarding anti-metastatic activity in human glioblastoma GBM 8401 cells.

RESULTS

The internalized amount of DMC has reached the highest level in GBM 8401 cells after 3 h treatment. Wound healing assay was used to determine cell mobility and results indicated that DMC suppressed cell movement of GBM 8401 cells. The transwell chamber assays were used for measuring cell migration and invasion and results indicated that DMC suppressed cell migration and invasion in GBM 8401 cells. Gelatin zymography assay was used to examine gelatinolytic activity (MMP-2) in conditioned media of GBM 8401 cells treated by DMC and results demonstrated that DMC significantly reduced MMP-2 activity. Western blotting showed that DMC reduced the levels of p-EGFR^(Tyr1068), GRB2, Sos1, p-Raf, MEK, p-ERK1/2, PI3K, p-Akt/PKBα^(Thr308), p-PDK1, NF-κB, TIMP-1, MMP-9, MMP-2, GSK3α/β, β-catenin, N-cadherin, and vimentin, but it elevated Ras and E-cadherin at 24 h treatment.

CONCLUSION

DMC inhibited cancer cell migration and invasion through inhibition of PI3K/Akt and NF-κB signaling pathways in GBM 8401 cells. We suggest that DMC may be used as a novel anti-metastasis agent for the treatment of human glioblastoma cancer in the future.

Lenvatinib Inhibits AKT/NF-κB Signaling and Induces Apoptosis Through Extrinsic/Intrinsic Pathways in Non-small Cell Lung Cancer

BACKGROUND/AIM

Non-small cell lung cancer (NSCLC) is a serious disease and the leading cause of death globally. Overexpression of protein kinase B/nuclear factor-kappa B (NF-κB) signaling transduction of NSCLC cells was recognized as a potential therapeutic target. Lenvatinib is a multiple kinase inhibitor against vascular endothelial growth factor receptor family. However, whether lenvatinib may affect AKT/NF-κB in NSCLC remains unknown.

MATERIALS AND METHODS

MTT assay, NF-κB reporter gene assay, flow cytometry, tranwell migration/invasion analysis and western blotting were used to identify the alteration of cell viability, NF-κB activation, apoptosis effect, migration/invasion potential and AKT/NF-κB related protein expression, respectively, in CL-1-5-F4 cells after lenvatinib treatment.

RESULTS

The cell viability and NF-κB activity were suppressed by lenvatinib. Extrinsic and intrinsic apoptosis were activated by lenvatinib. Additionally, the metastatic potential of CL-1-5-F4 cells was also suppressed by lenvatinib.

CONCLUSION

Altogether, lenvatinib induced extrinsic/intrinsic apoptosis and suppressed migration/invasion ability of NSCLC cells that was associated with AKT/NF-κB signaling inactivation.

Astragaloside IV Induces Apoptosis, G1-Phase Arrest and Inhibits Anti-apoptotic Signaling in Hepatocellular Carcinoma

BACKGROUND/AIM

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver and the third leading cause of cancer death worldwide. Although multiple chemotherapies options are available for HCC, chemo-induced toxicity is inevitable during clinical treatment. Therefore, identifying possible adjuvant agents with both liver-protective and antitumor effects is critical. Herbal medicines have chemopreventive and anti-HCC effect, such as Juzen taiho-to and Sho-saiko-to. Astragaloside IV is a compound extracted from the Chinese medical herb Astragalus membranaceus (Fisch.) Bge. with liver protection potential. However, whether astragaloside IV may also possess tumor-inhibitory capability and its underlying mechanism is remaining unknown.

MATERIALS AND METHODS

Viability analysis, cell-cycle analysis, apoptosis analysis, western blotting analysis and invasion trans-well assay were performed to identify tumor-inhibitory potential of astragaloside IV on HCC cells (SK-Hep1 and Hep3B cells).

RESULTS

We found that astragaloside IV may induce cytotoxicity and extrinsic/intrinsic apoptosis effect, but also trigger G₁ arrest in HCC cells. The expression of anti-apoptotic proteins of HCC were all reduced by astragaloside IV. Additionally, astragaloside IV also suppressed HCC cell invasion ability.

CONCLUSION

Astragaloside IV effectively suppressed HCC cell proliferation, invasion and anti-apoptosis in vitro.

Hyperforin induces apoptosis through extrinsic/intrinsic pathways and inhibits EGFR/ERK/NF-κB-mediated anti-apoptotic potential in glioblastoma

Glioblastoma is the most common primary brain tumor with poor survival rate and without effective treatment strategy. Notably, amplification and active mutation of epidermal growth factor receptor (EGFR) occur frequently in glioblastoma patient that may be a potential treatment target. Several studies indicated that various type of herbal compounds not only regulate anti-depressant effect but also shown capacity to suppress glioblastoma growth via inducing apoptosis and inhibiting oncogene signaling transduction. Hyperforin, an herb compound derived from St. John's wort was used to treat depressive disorder by inhibiting neuronal reuptake of several neurotransmitters. Although hyperforin can reduce matrix metallopeptidases-2 (MMPs) and -9-mediated metastasis of glioblastoma, the detail mechanism of hyperforin on glioblastoma is remaining unclear. Here, we suggested that hyperforin may induce extrinsic/intrinsic apoptosis and suppress anti-apoptotic related proteins expression of glioblastoma. We also indicated that hyperforin-mediated anti-apoptotic potential of glioblastoma was correlated to inactivation of EGFR/extracellular signal-regulated kinases (ERK)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling.

Glycyrrhizic Acid Modulates Apoptosis through Extrinsic/Intrinsic Pathways and Inhibits Protein Kinase B- and Extracellular Signal-Regulated Kinase-Mediated Metastatic Potential in Hepatocellular Carcinoma In Vitro and In Vivo

A previous study presented that glycyrrhizic acid as the hepatoprotective agent inhibits total parenteral nutrition-associated acute liver injury in rats. However, the anticancer effect and mechanism of glycyrrhizic acid in human hepatocellular carcinoma (HCC) is ambiguous. The purpose of the present study was to investigate the effect of glycyrrhizic acid on apoptosis dysregulation and metastatic potential in HCC in vitro and in vivo. Both SK-Hep1 and Hep3B cells were treated with different concentrations of glycyrrhizic acid for 24 or 48h. SK-Hep1/luc2 tumor-bearing mice were treated with vehicle or glycyrrhizic acid (50mg/kg/day by intraperitoneal injection) for 7 days. Tumor cells growth, apoptotic, and metastatic signaling transduction were evaluated by using MTT assay, digital caliper, bioluminescence imaging (BLI), flow cytometry, western blotting assay, and immunohistochemistry (IHC) staining. The results demonstrated glycyrrhizic acid significantly inhibits tumor cell growth, cell invasion, and expression of AKT (Ser473), extracellular-signal-regulated kinase (ERK), epidermal growth factor receptor (EGFR) phosphorylation, anti-apoptotic and metastatic proteins in HCC in vitro and in vivo. Glycyrrhizic acid also significantly triggered apoptosis and extrinsic/intrinsic apoptotic signaling transduction. In addition, PD98059 (ERK inhibitor) and LY294002 (AKT inhibitor) obviously reduced cell invasion and expression of metastasis-associated proteins. Taken together, these results indicated that glycyrrhizic acid induces apoptosis through extrinsic/intrinsic apoptotic signaling pathways and diminishes EGFR/AKT/ERK-modulated metastatic potential in HCC in vitro and in vivo.

Combinational treatment of 5-fluorouracil and casticin induces apoptosis in mouse leukemia WEHI-3 cells in vitro

Leukemia is one of the major diseases causing cancer-related deaths in the young population, and its cure rate is unsatisfying with side effects on patients. Fluorouracil (5-FU) is currently used as an anticancer drug for leukemia patients. Casticin, a natural polymethoxyflavone, exerts anticancer activity against many human cancer cell lines in vitro, but no other reports show 5-FU combined with casticin increased the mouse leukemia cell apoptosis in vitro. Herein, the antileukemia activity of 5-FU combined with casticin in WEHI-3 mouse leukemia cells was investigated in vitro. Treatment of two-drug combination had a higher decrease in cell viability and a higher increase in apoptotic cell death, the level of DNA condensation, and the length of comet tail than that of 5-FU or casticin treatment alone in WEHI-3 cells. In addition, the two-drug combination has a greater production rate of reactive oxygen species but a lower level of Ca²⁺ release and mitochondrial membrane potential (ΔΨ_m ) than that of 5-FU alone. Combined drugs also induced higher caspase-3 and caspase-8 activities than that of casticin alone and higher caspase-9 activity than that of 5-FU or casticin alone at 48 hours treatment. Furthermore, 5-FU combined with casticin has a higher expression of Cu/Zn superoxide dismutase (SOD [Cu/Zn]) and lower catalase than that of 5-FU or casticin treatment alone. The combined treatment has higher levels of Bax, Endo G, and cytochrome C of proapoptotic proteins than that of casticin alone and induced lower levels of B-cell lymphoma 2 (BCL-2) and BCL-X of antiapoptotic proteins than that of 5-FU or casticin only. Furthermore, the combined treatment had a higher expression of cleaved poly (ADP-ribose) polymerase (PARP) than that of casticin only. Based on these findings, we may suggest that 5-FU combined with casticin treatment increased apoptotic cell death in WEHI-3 mouse leukemia cells that may undergo mitochondria and caspases signaling pathways in vitro.

Partitioned Extracts of Bauhinia championii Induce G0/G1 Phase Arrest and Apoptosis in Human Colon Cancer Cells

Bauhinia championii (Benth.) is one of the commonly used herbs in Taiwan. The stem of this plant has been used to treat epigastria pain and rheumatoid arthritis. However, the antitumor activities of this herb have never been reported. This study aims to investigate the mechanism of anticancer activity of the extracts from B. championii (BC). BC was fractionated with a series of organic solvents, including n-hexane (H), ethyl acetate (EA), 1-butanol (B), and water (W). We first investigated the effects of BC-H, BC-EA, BC-B and BC-W partitioned fraction on cell viability. In HCT 116 colon cancer cell lines, BC-EA showed the highest inhibition of cell viability and changed the morphology of cells. With dose- and time-dependent manners, BC-EA inhibited the proliferation of HCT 116 cells by inducing apoptosis and G₀/G₁ phase arrest of cell cycle. To determine the underlying mechanisms, down-regulated CDK2, Cyclin D, and Cyclin E and up-regulated p16, p21, and p53 may account for the cell cycle arrest, while the apoptotic effect of BC-EA may attribute to increased intracellular Ca2+, loss of mitochondria membrane potential (ΔΨm), increase of Bax, Bak, puma, and AIF, and decrease of Bcl-2. Furthermore, the inactivation of Ras signaling pathway by BC-EA also contributed to its apoptotic effect on HCT 116. Our study demonstrates that BC-EA not only inhibits cell growth but also induces apoptosis through inhibiting Ras signal pathway and increasing p53 expression levels. We suggest that BC-EA may be a new dietary supplement and a useful tool to search for therapeutic candidates against colon cancer.

Cardamonin induces immune responses and enhances survival rate in WEHI-3 cell-generated mouse leukemia in vivo

Cardamonin, a monomeric alkaloid, is isolated from Alpinia conchigera Griff and other natural plants. Recently, it has been focused on its anticancer activities, and no information showing its immune effects on leukemia mice was reported. In this study, we investigated the immune effects of cardamonin on WEHI-3 cell-generated leukemia mice. Forty BALB/c mice were randomly divided into four groups: Group I mice were normal animals and groups II-IV were leukemia. Group II mice, as a positive control, were administered with normal diet, and group III and IV mice were treated with 1 and 5 mg/kg of cardamonin, respectively, by intraperitoneal injection every 2 days for 14 days. The population of white blood cells, macrophage phagocytosis, and the proliferations of T and B cells were analyzed by flow cytometry. Another forty mice were also separated randomly into four groups for the determination of survival rate. Results showed that cardamonin did not affect body weight. Cardamonin decreased CD3, CD11b, and Mac-3 cell populations but increased CD19 number. Cardamonin enhanced phagocytic abilities of macrophages from the peripheral blood mononuclear cells of leukemia mice. Furthermore, cardamonin at 1 mg/kg treatment improved the survival rate of leukemia mice in vivo. Therefore, cardamonin could be applied for a leukemia therapeutic reagent at a defined dose.

Hyperforin Induces Apoptosis Through Extrinsic/Intrinsic Pathways and Inhibits NF-ĸB-modulated Survival and Invasion Potential in Bladder Cancer

BACKGROUND/AIM

Muscle-invasive bladder cancer (MIBC) has long been recognized as a difficult to treat cancer type, thus a new treatment strategy is needed. The major purpose of the present study was to verify the anticancer effect of hyperforin and the mechanism through which it affects tumor cell growth and invasion in bladder cancer in vitro.

MATERIALS AND METHODS

Bladder cancer TSGH-8301 cells were treated with different concentrations of hyperforin for different durations of time. The changes in cell viability, production of calcium and reactive oxygen species (ROS), and anti-apoptotic signaling were evaluated using MTT assay, flow cytometry, and western blot analysis. The effect of hyperforin on the expression of nuclear factor-kappaB (NF-ĸB) p65 (Ser276), tumor progression-associated proteins, as well as on cell invasion was investigated using western blotting and cell invasion assay, respectively.

RESULTS

Hyperforin significantly induces apoptosis, extrinsic/intrinsic apoptotic signaling, accumulation of cytosol ROS, and calcium signalling. Hyperforin also significantly diminishes the expression of NF-ĸB p65 (Ser276), anti-apoptotic and tumor progression-associated proteins, as well as the cell invasion ability of TSGH-8301 cells.

CONCLUSION

Our findings demonstrate that hyperforin triggers apoptosis depending on extrinsic/intrinsic pathways and suppresses NF-ĸB-mediated cell survival as well as the invasive properties of bladder cancer in vitro.

Apoptosis induction and ERK/NF-κB inactivation are associated with magnolol-inhibited tumor progression in hepatocellular carcinoma in vivo

Although hepatitis B and/or hepatitis C virus were recognized as major risk factor for the development of hepatocellular carcinoma (HCC), certain occupational, environmental, and lifestyle factors also play key roles in HCC tumorigenesis. Moreover, in molecular signaling route, extracellular signal-regulated kinase (ERK)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling was found to be overexpressed and linked to poor prognosis in HCC. Thus, to identify possible nature compound that can suppress ERK/NF-κB may be benefit to HCC patient. Magnolol, a natural compound derived from herbal plant Magnolia officinalis, has been recognized as a liver protection and antitumor reagent. However, whether magnolol-inhibited HCC progression correlates with disruption of ERK/NF-κB signaling is remained unclear. In this studies, we performed SK-Hep1/luc2 HCC bearing animal model to investigate the anticancer efficacy and mechanism of magnolol on tumor progression. Tumor size and tumor growth rate were dramatically suppressed after treatment of magnolol. In addition, expression of phospho-ERK (p-ERK), NF-κB p65 (Ser536), and tumor progression-associated proteins, such as matrix metallopeptidase 9 (MMP-9), vascular endothelial growth factor (VEGF), X-linked inhibitor of apoptosis protein (XIAP), and CyclinD1 were all significantly decreased by magnolol. Most important, major extrinsic and intrinsic apoptosis signaling factors, including active caspase-8 and caspase-9 were both enhanced by magnolol. This study indicated that apoptosis induction through extrinsic/intrinsic pathways and blockage of ERK/NF-κB activation were associated with magnolol-inhibited tumor progression in HCC in vivo.

Tetramethylpyrazine reverses high-glucose induced hypoxic effects by negatively regulating HIF-1α induced BNIP3 expression to ameliorate H9c2 cardiomyoblast apoptosis

Background

Diabetic patients are highly vulnerable to hypoxic injury, which is associated with hypoxia induced BNIP3 expression that subsequently activate apoptosis. Our previous research show that Tetramethylpyrazine (TMP), a food flavoring agent, represses the hypoxia induced BNIP3 expression attenuate myocardial apoptosis. In this study, we evaluate the effect of TMP to provide protection against hypoxia aggravated high-glucose associated cellular apoptosis.

Methods

The cytoprotective effect of TMP against high glucose induced cellular damages was determined on embryo derived H9c2 cardiomyoblast cells that were subjected to 5% hypoxia for 24 h and subjected to different duration of 33 mM high glucose challenge. Further, the involvement of HIF-1α and BNIP3 in cellular damage and the mechanism of protection of TMP were determined by overexpression and silencing HIF-1α and BNIP3 protein expression.

Results

The results show that hypoxic effects on cell viability aggravates with high glucose challenge and this augmentative effect is mediated through BNIP3 in H9c2 cardiomyoblast cells. However, TMP administration effectively reversed the augmented HIF-1α levels and BNIP3 elevation. TMP improved the survival of H9c2 cells and effectively suppressed apoptosis in H9c2 cells. Further comparison on the effects of TMP on H9c2 cells challenged with high glucose and those challenged with hypoxia show that TMP precisely regulated the hypoxic intensified apoptotic effects in high-glucose condition.

Conclusion

The results clearly show that flavoring agent-TMP attenuates cytotoxicity amplified by hypoxia challenge in high glucose condition by destabilizing HIF-1α.

Casticin Induces DNA Damage and Affects DNA Repair Associated Protein Expression in Human Lung Cancer A549 Cells (Running Title: Casticin Induces DNA Damage in Lung Cancer Cells)

Casticin was obtained from natural plants, and it has been shown to exert biological functions; however, no report concerns the induction of DNA damage and repair in human lung cancer cells. The objective of this study was to investigate the effects and molecular mechanism of casticin on DNA damage and repair in human lung cancer A549 cells. Cell viability was determined by flow cytometric assay. The DNA damage was evaluated by 4',6-diamidino-2-phenylindole (DAPI) staining and electrophoresis which included comet assay and DNA gel electrophoresis. The protein levels associated with DNA damage and repair were analyzed by western blotting. The expression and translocation of p-H2A.X were observed by confocal laser microscopy. Casticin reduced total viable cell number and induced DNA condensation, fragmentation, and damage in A549 cells. Furthermore, casticin increased p-ATM at 6 h and increased p-ATR and BRCA1 at 6-24 h treatment but decreased p-ATM at 24-48 h, as well as decreased p-ATR and BRCA1 at 48 h. Furthermore, casticin decreased p-p53 at 6-24 h but increased at 48 h. Casticin increased p-H2A.X and MDC1 at 6-48 h treatment. In addition, casticin increased PARP (cleavage) at 6, 24, and 48 h treatment, DNA-PKcs and MGMT at 48 h in A549 cells. Casticin induced the expressions and nuclear translocation of p-H2AX in A549 cells by confocal laser microscopy. Casticin reduced cell number through DNA damage and condensation in human lung cancer A549 cells.

Combinational treatment of all-trans retinoic acid (ATRA) and bisdemethoxycurcumin (BDMC)-induced apoptosis in liver cancer Hep3B cells

The effects of two-drug combination, all-trans retinoic acid (ATRA) and bisdemethoxycurcumin (BDMC), on apoptosis induction of liver cancer cells were investigated in human liver Hep 3B cells. Two-drug combination caused a more effective decrease in cell viability and in induction of S phase arrest, DNA damage, and cell apoptosis than that of ATRA or BDMC only. Also, the two-drug combination caused more cells to undergo significantly increased ROS productions when compared to that of ATRA or BDMC only. Results of Western blotting demonstrated that two-drug combination increased expressions of Fas, pro-apoptotic proteins, and active form of caspase-3 and -9, but decreased that of anti-apoptotic proteins and XIAP than that of ATRA or BDMC only in Hep 3B cells. In conclusion, ATRA combined with BDMC enhance cell apoptosis and associated protein expression in Hep 3B cells. PRACTICAL APPLICATIONS: Bisdemethoxycurcumin (BDMC) derived from natural plants, turmeric (Curcuma longa), which had been used for Asia food for thousands of years. All-trans retinoid acid (ATRA) is currently used as a primary treatment for patients with acute promyelocytic leukemia. In previous study, ATRA and BDMC were reported to have anti-inflammatory and anticancer effects. Our results showed that treatment of ATRA combined with BDMC showed more effectively apoptosis than that of ATRA or BDMC only in Hep 3B cells. The findings also provided possible pathways concerning the induction of liver cancer cell apoptosis. We conclude that ATRA combined with BDMC may be potent anticancer agents or adjuvants for liver cancer therapy in the future.

Ouabain induces apoptotic cell death in human prostate DU 145 cancer cells through DNA damage and TRAIL pathways

Ouabain, a cardiotonic steroid and specific Na⁺ /K⁺ -ATPase inhibitor, has a potential to induce cancer cell apoptosis but the mechanisms of apoptosis induced by ouabain are not fully understand. The aim of this study was to investigate the cytotoxic effects of ouabain on human prostate cancer DU 145 cells in vitro. Cell morphological changes were examined by phase contrast microscopy. Cell viability, cell cycle distribution, cell apoptosis, DNA damage, the production of ROS and Ca²⁺ , and mitochondrial membrane potential (ΔΨ_m ) were measured by flow cytometry assay. Results indicated that ouabain induced cell morphological changes, decreased total cell viability, induced G0/G1 phase arrest, DNA damage, and cell apoptosis, increased ROS and Ca²⁺ production, but decreased the levels of ΔΨ_m in DU 145 cells. Ouabain also increased the activities of caspase-3, -8, and -9. Western blotting was used for measuring the alterations of apoptosis-associated protein expressions in DU 145 cells and results indicated that ouabain increased the expression of DNA damage associated proteins (pATM^Ser1981 , p-H2A.X^Ser139 , and p-p53^Ser15 ) and ER-stress-associated proteins (Grp78, ATF6β, p-PERK^Thr981 , PERK, eIF2A, GADD153, CaMKIIβ, and caspase-4) in time-dependently. Furthermore, ouabain increased apoptosis-associated proteins (DR4, DR5, Fas, Fas Ligand, and FADD), TRAIL pathway, which related to extrinsic pathway, promoted the pro-apoptotic protein Bax, increased apoptotic-associated proteins, such as cytochrome c, AIF, Endo G, caspase-3, -8, and -9, but reduced anti-apoptotic protein Bcl-2 and Bcl-x in DU 145 cells. In conclusion, we may suggest that ouabain decreased cell viability and induced apoptotic cell death may via caspase-dependent and mitochondria-dependent pathways in human prostate cancer DU 145 cells.

Lupeol suppresses migration and invasion via p38/MAPK and PI3K/Akt signaling pathways in human osteosarcoma U-2 OS cells

Lupeol, one of the common components from the fruits and natural foods, has been reported to exert antitumor activities in many human cancer cell lines; however, its effects on osteosarcoma cell metastasis were not elucidated. In the present study, lupeol at 10–25 μM induced cell morphological changes and decreased total viable cell number in U-2 OS cells. Lupeol (5–15 μM) suppressed cell mobility, migration, and invasion by wound healing and transwell chamber assays, respectively. Lupeol inhibited the activities of MMP-2 and −9 in U-2 OS cells by gelatin zymography assay. Lupeol significantly decreased PI3K, pAKT, β-catenin, and increased GSK3β. Furthermore, lupeol decreased the expressions of Ras, p-Raf-1, p-p38, and β-catenin. Lupeol also decreased uPA, MMP-2, MMP-9, and N-cadherin but increased VE-cadherin in U-2 OS cells. Based on these observations, we suggest that lupeol can be used in anti-metastasis of human osteosarcoma cells in the future.

Ursolic acid induces apoptosis and autophagy in oral cancer cells

Oral squamous cell carcinoma (OSCC) is the fifth common cause of cancer mortality in Taiwan with high incidence and recurrence and needs new therapeutic strategies. In this study, ursolic acid (UA), a triterpenoid, was examined the antitumor potency in OSCC cells. Our results showed that UA inhibited the proliferation of OSCC cells in a dose- and time-dependent manner in both Ca922 and SCC2095 oral cancer cells. UA induced caspase-dependent apoptosis accompanied with the modulation of various biological biomarkers including downregulating Akt/mTOR/NF-κB signaling, ERK, and p38. In addition, UA inhibited angiogenesis as evidenced by abrogation of migration/invasion and blocking MMP-2 secretion in Ca922 cells. Interestingly, UA induced autophagy in OSCC cells, as manifested by LC3B-II conversion and increased p62 expression and accumulation of autophagosomes. Inhibition by autophagy inhibitor enhanced UA-mediated apoptosis in Ca922 cells. The experiment provides a rationale for using triterpenoid in the treatment of OSCC.

Cantharidin decreased viable cell number in human osteosarcoma U-2 OS cells through G2/M phase arrest and induction of cell apoptosis

Cantharidin (CTD), a sesquiterpenoid bioactive substance, has been reported to exhibit anticancer activity against various types of cancer cells. The aim of the present study was to investigate the apoptosis effects and the underlying mechanisms of CTD on osteosarcoma U-2 OS cells. Results showed that CTD induced cell morphologic changes, reduced total viable cells, induced DNA damage, and G₂/M phase arrest. CTD increased the production of reactive oxygen species and Ca²⁺, and elevated the activities of caspase-3 and -9, but decreased the level of mitochondrial membrane potential. Furthermore, CTD increased the ROS- and ER stress-associated protein expressions and increased the levels of pro-apoptosis-associated proteins, but decreased that of anti-apoptosis-associated proteins. Based on these observations, we suggested that CTD decreased cell number through G₂/M phase arrest and the induction of cell apoptosis in U-2 OS cells and CTD could be a potential candidate for osteosarcoma treatments.

High-density lipoprotein ameliorates palmitic acid-induced lipotoxicity and oxidative dysfunction in H9c2 cardiomyoblast cells via ROS suppression

Background

High levels circulating saturated fatty acids are associated with diabetes, obesity and hyperlipidemia. In heart, the accumulation of saturated fatty acids has been determined to play a role in the development of heart failure and diabetic cardiomyopathy. High-density lipoprotein (HDL) has been reported to possess key atheroprotective biological properties, including cellular cholesterol efflux capacity, anti-oxidative and anti-inflammatory activities. However, the underlying mechanisms are still largely unknown. Therefore, the aim of the present study is to test whether HDL could protect palmitic acid (PA)-induced cardiomyocyte injury and explore the possible mechanisms.

Results

H9c2 cells were pretreated with HDL (50–100 μg/ml) for 2 h followed by PA (0.5 mM) for indicated time period. Our results showed that HDL inhibited PA-induced cell death in a dose-dependent manner. Moreover, HDL rescued PA-induced ROS generation and the phosphorylation of JNK which in turn activated NF-κB-mediated inflammatory proteins expressions. We also found that PA impaired the balance of BCL₂ family proteins, destabilized mitochondrial membrane potential, and triggered subsequent cytochrome c release into the cytosol and activation of caspase 3. These detrimental effects were ameliorated by HDL treatment.

Conclusion

PA-induced ROS accumulation and results in cardiomyocyte apoptosis and inflammation. However, HDL attenuated PA-induced lipotoxicity and oxidative dysfunction via ROS suppression. These results may provide insight into a possible molecular mechanism underlying HDL suppression of the free fatty acid-induced cardiomyocyte apoptosis.

Amentoflavone Effectively Blocked the Tumor Progression of Glioblastoma via Suppression of ERK/NF- κ B Signaling Pathway

Glioblastoma is the most common primary malignant tumor of the central nervous system, with an annual incidence of 5.26 per 100000 people. The clinical outcome of standard therapy and the survival rate remain poor; therefore, there is an unmet need for a new strategy to treat this lethal disease. Although amentoflavone was known to have anticancer potential in various types of cancers, its antiglioblastoma ability and mechanism remain unrecognized. We demonstrated that amentoflavone may suppress glioblastoma invasion and migration by transwell assay. Moreover, we established NF- κ B reporter gene system and used that for verifying NF- κ B inhibition efficacy of amentoflavone on in vitro and in vivo studies. Here, we indicated that amentoflavone not only diminished NF- κ B activation, but also reduced NF- κ B-mediated downstream oncogenes expression, such as MMP-2, MMP-9, XIAP, cyclinD1 and VEGF, which was elucidated by Western blot and immunohistochemistry (IHC). Tumor growth inhibition and NF- κ B reduction was found in the amentoflavone treatment group, which was revealed by the glioblastoma-bearing animal model. In this study, we also used ERK inhibitor and NF- κ B inhibitor (QNZ) to confirm whether the beneficial result of amentoflavone on glioblastoma was mainly regulated by blockage of ERK/NF- κ B signaling. In summary, ERK/NF- κ B signaling pathway has a role in the inhibition of tumor growth by amentoflavone in glioblastoma.

Casticin inhibits human prostate cancer DU 145 cell migration and invasion via Ras/Akt/NF-κB signaling pathways

Casticin, a polymethoxyflavone derived from natural plants, has biological activities including induction of cell apoptosis. In this study, we showed the beneficial effects of casticin on the inhibition of prostate cancer cell metastasis. Casticin reduced total viable cell number, thus, we selected low doses of casticin for following experiments. Casticin decreased cell mobility, suppressed cell migration and invasion, and reduced cell gelatinolytic activities of MMP-2/-9. Furthermore, casticin inhibited the protein levels of AKT, GSK3 αβ, Snail, and MMPs (MMP-2, -9, -13, and -7) at 24 and 48 hr treatment. Casticin diminished the expressions of NF-κB p65, GRB2, SOS-1, MEK, p-ERK1/2, and p-JNK1/2 at 48 hr treatment only. However, casticin reduced the level of E-cadherin at 24 hr treatment but elevated at 48 hr. The novel findings suggest that casticin may represent a new and promising therapeutic agent for the metastatic prostate cancer. PRACTICAL APPLICATIONS: Casticin derived from natural plants had been used for Chinese medicine in Chinese population for thousands of years. In the present study, casticin attenuated metastatic effects, including decreasing viable cell number, inhibiting the migration, invasion, and adhesion, and reducing matrix metalloproteinases activity on human prostate DU 145 cancer cells. In addition, the results also provided possible pathways involved in casticin anti-metastasis mechanism. We conclude that casticin may be an aptitude anticancer agent or adjuvant for the metastatic prostate cancer in the future.

Fisetin Inhibits Cell Proliferation through the Induction of G0/G1 Phase Arrest and Caspase-3-Mediated Apoptosis in Mouse Leukemia Cells

Fisetin, a naturally occurring flavonoid, is found in common fruits and vegetables and has been shown to induce cytotoxic effects in many human cancer cell lines. No information has shown that fisetin induced cell cycle arrest and apoptosis in mouse leukemia WEHI-3 cells. We found that fisetin decreased total viable cells through G₀/G₁ phase arrest and induced sub-G₁ phase (apoptosis). We have confirmed fisetin induced cell apoptosis by the formation of DNA fragmentation and induction of apoptotic cell death. Results indicated that fisetin induced intracellular Ca 2+ increase but decreased the ROS production and the levels of ΔΨ m in WEHI-3 cells. Fisetin increased the activities of caspase-3, -8 and -9. Cells were pre-treated with inhibitors of caspase-3, -8 and -9 and then treated with fisetin and results showed increased viable cell number when compared to fisetin treated only. Fisetin reduced expressions of cdc25a but increased p-p53, Chk1, p21 and p27 that may lead to G₀/G₁ phase arrest. Fisetin inhibited anti-apoptotic protein Bcl-2 and Bcl-xL and increased pro-apoptotic protein Bax and Bak. Furthermore, fisetin increased the protein expression of cytochrome c and AIF. Fisetin decreased cell number through G₀/G₁ phase arrest via the inhibition of cdc25c and induction of apoptosis through caspase-dependent and mitochondria-dependent pathways. Therefore, fisetin may be useful as a potential therapeutic agent for leukemia.

Fisetin Suppresses Human Osteosarcoma U-2 OS Cell Migration and Invasion via Affecting FAK, uPA and NF-ĸB Signaling Pathway In Vitro

BACKGROUND/AIM

Evidence has indicated that fisetin induces cytotoxic effects in human cancer cell lines, including the inhibition of cell migration and invasion, however, the exact molecular mechanism of action of fisetin in human osteosarcoma cells remains unclear.

MATERIALS AND METHODS

The anti-metastatic mechanisms of fisetin in human osteosarcoma U-2 OS cells were investigated in vitro.

RESULTS

Fisetin reduced the viability of cells at different concentrations (2.5, 5 and 10 μM) as measured by flow cytometric assay. Fisetin suppressed cell mobility, migration and invasion of U-2 OS cells, as shown by wound healing assay and transwell filter chambers, respectively. The gelatin zymography assay showed that fisetin inhibited MMP-2 activity in U-2 OS cells. Results from western blotting indicated that fisetin reduced the levels of pEGFR, SOS-1, GRB2, Ras, PKC, p-ERK1/2, p-JNK, p-p-38, VEGF, FAK, RhoA, PI3K, p-AKT, NF-ĸB, uPA, MMP-7, MMP-9, and MMP-13, but increased GSK3β and E-cadherin in U-2 OS cells after 48 h of treatment.

CONCLUSION

Fisetin can be used in the future, as a target for the treatment of metastasis of human osteosarcoma cells.

Ouabain promotes immune responses in WEHI-3 cells to generate leukemia mice through enhancing phagocytosis and natural killer cell activities in vivo

Ouabain, a cardiotonic steroid, was used for the treatment of heart failure and atrial fibrillation and induces cancer cell apoptosis in many human cancer cells including human leukemia cells. However, there are no reports to show the effects on immune responses in a leukemia mouse model. In this study, WEHI-3 cell generated leukemia mice were developed and treated by oral ouabain at 0, 0.75, 1.5, and 3 mg/kg for 15 days. Results indicated that ouabain did not affect body appearance, but decreased liver and spleen weights, B- and T-cell proliferation at all three doses treatment and increased CD19 cells at 3.0 mg/kg treatment, decreased CD3, CD11b, and Mac-3 cells levels compared with positive control. Furthermore, ouabain increased the macrophage phagocytosis from peripheral blood mononuclear cell and peritoneal cavity at all three doses treatment and increased NK cell activities. Ouabain restored GOT, GPT and LDH levels in WEHI-3 leukemia mice in vivo.

Casticin Induces DNA Damage and Impairs DNA Repair in Human Bladder Cancer TSGH-8301 Cells

BACKGROUND/AIM

Casticin shows anti-cancer effects in many types of cancer. However, there is no information regarding its role in DNA damage in human bladder cancer. The aim of this study was to investigate the effects of casticin on TSGH-8301 cells in vitro.

MATERIALS AND METHODS

Viability of cells was assayed by flow cytometry. DNA damage was assayed by DAPI staining, comet assay, and gel electrophoresis. Protein levels were examined by western blotting and confocal laser microscopy.

RESULTS

Casticin decreased viability of cells and induced DNA damage. Furthermore, casticin decreased expression of p-ATM, p-ATR, MDC1 and MGMT levels after 48 h of treatment, however, it increased p-ATR and MGMT levels after 12 h. In contrast, casticin increased the levels of p-p53, p-H2A.X, and PARP after 48 h of treatment. As shown by confocal microscopy, casticin affected the translocation of DNA-PKcs and p-p53 to the nucleus of TSGH-8301 cells.

CONCLUSION

Casticin decreased viability of human bladder cancer cells through DNA damage.

Maslinic Acid Enhances Immune Responses in Leukemic Mice Through Macrophage Phagocytosis and Natural Killer Cell Activities In Vivo

BACKGROUND/AIM

Maslinic acid (MA), a pentacyclic triterpene extracted from wax-like coatings of olives, has been shown to reduce cancer cell number through induction of autophagy and apoptosis in many human cancer cells including human leukemia HL-60 cells. In the present study, we investigated whether or not MA affects immune responses in a leukemia mouse model.

MATERIALS AND METHODS

WEHI-3 cells were intraperitonealIy (i.p.) injected into normal BALB/c mice to develop leukemia. Mice were then treated by i.p. injection with MA at different doses (0, 8, 16 and 32 mg/kg) for 2 weeks. After treatment, all animals were weighed and blood, liver and spleen tissues were weighed. Blood or spleen both were used for determination of cell markers or phagocytosis, natural killer (NK) cell activities and T- and B-cell proliferation, respectively, by using a flow cytometric assay.

RESULTS

MA did not significantly affect body, liver, and spleen weights. However, MA increased markers of T-cells (at 16 mg/kg treatment) and monocytes (at 32 mg/kg treatment), but reduced B-cell markers (at 8 mg/kg treatment); MA did not significantly affect cell marker of macrophages. Furthermore, MA increased phagocytosis by macrophages from peripheral blood mononuclear cells and peritoneal cavity at 32 mg/kg treatment and increased NK cell activity at target cell:splenocyte ratio of 25:1 but did not affect B- and T-cell proliferation.

CONCLUSION

MA increased immune responses by enhancing macrophage phagocytosis and NK cell activities in leukemic mice.

Chrysin inhibit human melanoma A375.S2 cell migration and invasion via affecting MAPK signaling and NF-κB signaling pathway in vitro

Numerous evidences have shown that chrysin induced cytotoxic effects via induced cell cycle arrest and induction of cell apoptosis in human cancer cell lines, however, no information showed that chrysin inhibited skin cancer cell migration and invasion. In this study, we investigated anti-metastasis mechanisms of chrysin in human melanoma cancer A375.S2 cells in vitro. Under sub-lethal concentrations of chrysin (0, 5, 10, and 15 μM) which inhibits cell mobility, migration and invasion of A375.S2 cells that were assayed by wound healing and Transwell filter. That chrysin inhibited MMP-2 activity in A375.S2 cells was investigated by gelatin zymography assay. Western blotting was used to examine protein expression and results indicated that chrysin inhibited the expression of GRB2, SOS-1, PKC, p-AKT (Thr308), NF-κBp65, and NF-κBp50 at 24 and 48 hours treatment, but only at 10-15 μM of chrysin decreased Ras, PI3K, p-c-Jun, and Snail only at 48 hours treatment and only decrease p-AKT(Ser473) at 24 hours treatment. Furthermore, chrysin (5-15 μM) decreased the expression of uPA, N-cadherin and MMP-1 at 24 and 48 hours treatment but only decreased MMP-2 and VEGF at 48 hours treatment at 10-15 μM and 5-15 μM of chrysin, respectively, however, increased E-cadherin at 5-15 μM treatment. Results of confocal laser microscopy systems indicated that chrysin inhibited expression of NF-κBp65 in A375.S2 cells. Based on these observations, we suggest that chrysin can be used in anti-metastasis of human melanoma cells in the future.

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 ΔΨ_m 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 ΔΨ_m 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.

Tetrandrine inhibits human brain glioblastoma multiforme GBM 8401 cancer cell migration and invasion in vitro

Tetrandrine (TET) has been reported to induce anti-cancer activity in many human cancer cells and also to inhibit cancer cell migration and invasion. However, there are no reports to show TET inhibits cell migration and invasion in human brain glioblastoma multiforme GBM 8401 cells. In this study, we investigated the anti-metastasis effects of TET on GBM 8401 cells in vitro. Under sub-lethal concentrations (from 1, 5 up to 10 μM), TET significantly inhibited cell mobility, migration and invasion of GBM 8401 cells that were assayed by wound healing and Transwell assays. Gelatin zymography assay showed that TET inhibited MMP-2 activity in GBM 8401 cells. Western blotting results indicated that TET inhibited several key metastasis-related proteins, such as p-EGFR_(Tyr1068) , SOS-1, GRB2, Ras, p-AKT_(Ser473) and p-AKT_(Thr308) , NF-κB-p65, Snail, E-cadherin, N-cadherin, NF-κB, MMP-2 and MMP-9 that were significant reduction at 24 and 48 hours treatment by TET. TET reduced MAPK signaling associated proteins such as p-JNK1/2 and p-c-Jun in GBM 8401 cells. The electrophoretic mobility shift (EMSA) assay was used to investigate NF-κB and DNA binding was reduced by TET in a dose-dependently. Based on these findings, we suggested that TET could be used in anti-metastasis of human brain glioblastoma multiforme GBM 8401 cells in the future.

Ursolic Acid Induces Apoptotic Cell Death Through AIF and Endo G Release Through a Mitochondria-dependent Pathway in NCI-H292 Human Lung Cancer Cells In Vitro

BACKGROUND/AIM

Ursolic acid (UA), a triterpene compound present in natural plants, has been shown to induce cytotoxic effects on many human cancer cells through induction of cell-cycle arrest and apoptosis. This study investigated the effects of UA on human lung cancer NCI-H292 cells in vitro.

MATERIALS AND METHODS

Flow cytometric assay was used to measure the percentage of cell viability, apoptotic cell death by double staining of annexin V and propidium iodide (PI), production of reactive oxygen species (ROS) and Ca2+, and mitochondriaI membrane potential (Ψm). UA-induced chromatin condensation and DNA fragmentation were examined by 4',6-diamidino-2-phenylindole staining and DNA gel electrophoresis, respectively. Western blotting was used to examine the changes of apoptosis-associated protein expression in NCI-H292 cells.

RESULTS

UA reduced cell viability and induced apoptotic cell death. UA increased Ca2+ production, reduced Ψm, but did not affect ROS production in NCI-H292 cells. UA increased apoptosis-inducing factor (AIF) and endonuclease G in NCI-H292 cells.

CONCLUSION

Based on these observations, we suggest UA induces apoptotic cell death via AIF and Endo G release through a mitochondria-dependent pathway in NCI-H292 cells.

Casticin Promotes Immune Responses, Enhances Macrophage and NK Cell Activities, and Increases Survival Rates of Leukemia BALB/c Mice

Casticin, derived from Fructus Viticis, has anticancer properties in many human cancer cells, however, there is no report to show that casticin promotes immune responses and affects the survival rate of leukemia mice in vivo. The aim of this study is to evaluate the effects of casticin on immune responses and the survival rate of WEHI-3 cells generated in leukemia mice in vivo. Animals were divided into six groups: normal control mice, leukemia control mice, mice treated with ATRA (all-trans retinoic acid), and casticin (0.1, 0.2, and 0.4[Formula: see text]mg/kg) treated mice. All animals were treated for 14 days and then measured for body weights, total survival rate, cell markers, the weights of liver and spleen, phagocytosis of spleen cells, NK cell activities and cell proliferation. Results show that casticin did not affect animal appearances, however, it increased body weights and decreased the weights of liver at 0.2[Formula: see text]mg/kg and 0.4[Formula: see text]mg/kg treatment. Casticin also decreased spleen weight at 0.2[Formula: see text]mg/kg and 0.4[Formula: see text]mg/kg treatment, increased CD3 at 0.1, 0.2 and 0.4[Formula: see text]mg/kg doses and increased CD19 at 0.2[Formula: see text]mg/kg treatment but decreased CD11b and Mac-3 at 0.1, 0.2 and 0.4[Formula: see text]mg/kg treatment. Casticin (0.1, 0.2 and 0.4[Formula: see text]mg/kg) increased macrophage phagocytosis from PBMC (peripheral blood mononuclear cell) and peritoneal cavity. Furthermore, casticin increased NK cells’ cytotoxic activity and promoted T cell proliferation at 0.1–0.4[Formula: see text]mg/kg treatment with or without concanavalin A (Con A) stimulation, but only increased B cell proliferation at 0.1 mg/kg treatment. Based on these observations, casticin could be used as promoted immune responses in leukemia mice in vivo.

Etomidate Suppresses Invasion and Migration of Human A549 Lung Adenocarcinoma Cells

BACKGROUND/AIM

Etomidate, an intravenous anesthetic, has been shown to have anticancer effects, including induction of cell-cycle arrest and apoptosis. However, to our knowledge, there are no reports about the anti-metastasis effects of etomidate on A549 human lung adenocarcinoma cells.

MATERIALS AND METHODS

The cell viability, cell adhesion, gelatin zymography assay, transwell migration and invasion assay, and western blotting analysis were used to investigate the effects of etomidate on A549 cells.

RESULTS

In our study, etomidate showed low cytotoxicity, inhibited cell adhesion, and suppressed the migration and invasion in A549 cells. The activity of matrix metallopeptidase 2 (MMP2) was reduced by 48 h treatment of etomidate. Results of western blotting analysis indicated that etomidate down-regulated the expression of protein kinase C, MMP7, MMP1, MMP9, and p-p-38, but up-regulated that of RAS, phosphoinositide 3-kinase, and phosphor-extracellular-signal related kinase after 24 and 48 h treatment, in A549 cells.

CONCLUSION

Etomidate suppressed the migration and invasion of lung adenocarcinoma A549 cells via inhibiting the expression of MMP1, MMP2, MMP7 and MMP9, and provides potential therapeutic targets for lung cancer treatment.

Bufalin Induces Apoptotic Cell Death in Human Nasopharyngeal Carcinoma Cells through Mitochondrial ROS and TRAIL Pathways

The aim of this study was to investigate the effects of bufalin on human nasopharyngeal carcinoma NPC-TW 076 cells in vitro. Bufalin is a cardiotonic steroid and a key active ingredient of the Chinese medicine ChanSu. The extracts of Chansu are used for various cancer treatments in China. In the present study, bufalin induced cell morphological changes, decreased total cell viability and induced G2/M phase arrest of cell cycle in NPC-TW 076 cells. Results also indicated that bufalin induced chromatin condensation (cell apoptosis) and DNA damage by DAPI staining and comet assay, respectively. The induced apoptotic cell death was further confirmed by annexin-V/PI staining assay. In addition, bufalin also increased ROS and Ca[Formula: see text] production and decreased the levels of [Formula: see text]. Furthermore, the alterations of ROS, ER stress and apoptosis associated protein expressions were investigated by Western blotting. Results demonstrated that bufalin increased the expressions of ROS associated proteins, including SOD (Cu/Zn), SOD2 (Mn) and GST but decreased that of catalase. Bufalin increased ER stress associated proteins (GRP78, IRE-1[Formula: see text], IRE-1[Formula: see text], caspase-4, ATF-6[Formula: see text], Calpain 1, and GADD153). Bufalin increased the pro-apoptotic proteins Bax, and apoptotic associated proteins (cytochrome c, caspase-3, -8 and -9, AIF and Endo G) but reduced anti-apoptotic protein Bcl-2 in NPC-TW 076 cells. Furthermore, bufalin elevated the expressions of TRAIL-pathway associated proteins (TRAIL, DR4, DR5, and FADD). Based on these findings, we suggest bufalin induced apoptotic cell death via caspase-dependent, mitochondria-dependent and TRAIL pathways in human nasopharyngeal carcinoma NPC-TW 076 cells.

Cardamonin Induces Cell Cycle Arrest, Apoptosis and Alters Apoptosis Associated Gene Expression in WEHI-3 Mouse Leukemia Cells

Cardamonin, the chalcone class, is one of the natural components from the spicy herbaceous plant (Alpinia conchigera Griff) and has anticancer activities in many human cancer cell lines. There is, however, no information to show that cardamonin induces cell apoptosis and alters apoptosis associated gene expressions in mouse leukemia cells. Thus, we investigated the effects of cardamonin on the apoptotic cell death and associated gene expression in mouse leukemia WEHI-3 cells in vitro. Results indicated that cardamonin decreased total viable cell number via induced cell morphological changes and apoptotic cell death in WEHI-3 cells that were assay by contrast-phase microscopy and flow cytometry examinations, respectively. The flow cytometry assay indicated that cardamonin increased reactive oxygen species (ROS) and Ca[Formula: see text] production, decreased the levels of mitochondrial membrane potential ([Formula: see text] and increased caspase-3, -8 and -9 activities in WEHI-3 cells. Western blotting was performed to analyze expression of relevant pro- and anti-apoptotic proteins and results showed that cardamonin decreased anti-apoptotic protein of Bcl-2 but increased pro-apoptotic protein of Bax in WEHI-3 cells. Furthermore, cardamonin increased cytochrome c, AIF and Endo G release, increased GRP78, caspase-12 that were associated with ER stress and increased Fas, Fas-Ligand and FADD expression. Furthermore, cardamonin increased the gene expressions of DAP (death-associated protein), TMBIM4 transmembrane (BAX inhibitor motif containing 4), ATG5 (autophagy related 5) but decreased the gene expression of DDIT3 (DNA-damage inducible transcript 3), DDIT4 (DNA-damage-inducible transcript 4), BAG6 (BCL2-associated athanogene 6), BCL2L13 [BCL2-like 13 (apoptosis facilitator)] and BRAT1 (BRCA1-associated ATM activator 1) that are associated with apoptosis pathways. Based on those findings, we may suggest cardamonin induced apoptotic cell death through Fas and Fas-Ligand-, caspase- and mitochondria-dependently pathways and also affects the apoptotic gene expression in WEHI-3 cells in vitro.

Lauryl Gallate Induces Apoptotic Cell Death through Caspase-dependent Pathway in U87 Human Glioblastoma Cells In Vitro

BACKGROUND/AIM

The treatment of human glioma tumor is still an unmet medical need. Natural products are always promising resources for discovery of anticancer drugs. Lauryl gallate (LG) is one of the derivatives of gallic acid, widely present in plants, that has been shown to induce anticancer activities in many human cancer cell lines; however, it has not been studied in human glioma cell lines. Thus, the effects of LG on human glioblastoma U87 cells were investigated in the present in vitro study.

MATERIALS AND METHODS

Cell morphology and viability were examined by phase-contrast microscopy. Annexin V/Propidium iodide (PI) double staining were performed and assayed by flow cytometry to confirm that viable cell number reduction was due to the induction of apoptosis. Furthermore, U87 cells were exposed to LG in various concentrations and were analyzed by caspase activity assay. To further confirm that LG induced apoptotic cell death, the expression of apoptosis-associated proteins in LG-treated U87 cells was tested by western blot.

RESULTS

LG induced morphological changes and decreased viability in U87 cells. Annexin V/PI double staining revealed that LG induced apoptotic cell death in U87 cells in a dose-dependent manner. The increased activities of caspase-2, -3, -8 and -9 demonstrated that LG induced U87 cell apoptosis through a caspase-dependent pathway. In terms of molecular level, LG increased pro-apoptotic proteins Bax and Bak and decreased anti-apoptotic protein Bcl-2 in U87 cells. Furthermore, LG also suppressed the expression of p-Akt, Pak1, Hif-1α and Hif-2α, β-catenin and Tcf-1 in U87 cells.

CONCLUSION

These results suggest that LG induced apoptotic cell death via the caspase-dependent pathway in U87 cells.

Bufalin Enhances Immune Responses in Leukemic Mice Through Enhancing Phagocytosis of Macrophage In Vivo

BACKGROUND/AIM

Bufalin, bufadienolide present in Chan Su, has been shown to induce cancer cell apoptosis in many human cancer cells, including human leukemia cells, but its effects on immune responses are unknown.

MATERIALS AND METHODS

This study investigated whether bufalin affected immune responses of mice with WEHI-3 cell-generated leukemia in vivo. BALB/c mice were intraperitoneally injected with WEHI-3 cells to develop leukemia and then were treated with oral treatment with bufalin at different doses (0, 0.1, 0.2 and 0.4 mg/kg) for 2 weeks. At the end of treatment, all mice were weighted and blood was collected; liver and spleen tissues were collected for cell marker, phagocytosis, natural killer (NK) cell activity and T- and B-cell proliferation measurements by using flow cytometric assays.

RESULTS

When compared with the leukemia control group, bufalin increased the body weight, but reduced liver and spleen weights, and reduced CD3, CD16 and Mac-3 cell markers at 0.4 mg/kg treatment and increased CD11b marker at 0.1 and 0.2 mg/kg treatment. Furthermore, bufalin at 0.4 mg/kg increased phagocytosis by macrophages isolated from peripheral blood mononuclear cells and at 0.1 mg/kg by those from the peritoneal cavity. Bufalin (0.2 and 0.4 mg/kg) increased NK cell cytotoxic activity at effector:target ratio of 50:1. Bufalin increased B-cell proliferation at 0.1 and 0.2 mg/kg treatment but only increased T-cell proliferation at 0.1 mg/kg. Bufalin increased glutamate oxaloacetate transaminase level at all dose treatments, increased glutamic pyruvic transaminase level only at 0.1 mg/kg treatment, but reduced the level of lactate dehydrogenase at all dose levels in mice with WEHI-3 cell-induced leukemia in vivo.

CONCLUSION

Bufalin increased immune responses by enhancing phagocytosis in mice with leukemia mice.

Antitumor Ability of KT2 Peptide Derived from Leukocyte Peptide of Crocodile Against Human HCT116 Colon Cancer Xenografts

BACKGROUND/AIM

Many antimicrobial peptides have been shown to have anticancer activity against human cancer cell lines. Cationic KT2 peptide, derived from white blood cell extract of Crocodylus siamensis has antibacterial activity and antitumor activity against human cervical cancer cells, but there are no data on the effect of KT2 peptide on tumor growth in vivo. The anticancer activity of KT2 peptide on human colon cancer xenografts was investigated in nude mice.

MATERIALS AND METHODS

Tumors in nude mice (BALB/c -nu/nu mice) were induced by subcutaneous injection with HCT116 cells. Twelve days after cancer cell xenograft, mice were treated by intratumoral injection with phosphate-buffered saline or KT2 peptide (25 and 50 mg/kg) once every 2 days for a total of four times and mice were sacrificed at 2 days after the last treatment.

RESULTS

KT2 peptide treatment did not lead to significant difference in mouse body weight among groups, but reduced both tumor volume and weight of colon cancer xenografts. Moreover, KT2 peptide increased the expression of apoptotic proteins, such as BCL2-associated X (BAX), cleaved caspase-3, and poly (ADP-ribose) polymerase and reduced that of BCL2 apoptosis regulator in xenograft tumors.

CONCLUSION

This finding suggests that KT2 peptide may inhibit tumor growth via apoptosis induction in this mouse model and supports the antitumor ability of KT2 peptide.