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Triple negative breast cancer (TNBC) is one of the leading causes of cancer death in the world and lacks an effective targeted therapy. G-protein-coupled receptor 161 (GPR161) has been demonstrated to perform the functional regulations on TNBC progression and might be a potential new target for TNBC therapy. This study showed the effects of bisdemethoxycurcumin (BDMC) on GPR161 regulation, indicating that BDMC effectively inhibited GPR161 expression and downregulated GPR161-driven signaling. BDMC showed the potent inhibitory effects on TNBC proliferation through suppressing GPR161-mediated mammalian target of rapamycin (mTOR)/70 kDa ribosomal protein S6 kinase (p70S6K) activation. Besides, in this study, we discover the mechanism of GPR161-driven TNBC metastasis, linking to GPR161-mediated twist-related protein 1 (Twist1)/matrix metallopeptidase 9 (MMP9) contributing to the epithelial-mesenchymal transition (EMT). BDMC effectively repressed GPR161-mediated TNBC metastasis via inhibiting Twist1/MMP9-induced EMT. The three-dimensional invasion assay also showed that BDMC significantly inhibited TNBC invasion. The combination treatment of BDMC and rapamycin enhanced the inhibition of TNBC proliferation and metastasis through increasing the blockage of mTOR activation. Furthermore, this study also observed that BDMC activated the caspase 3/9 signaling pathway to induce TNBC apoptosis. Therefore, BDMC could be applicable to anticancer therapy, especially targeting on the GPR161-driven cancer type.

Tumor necrosis factor-related apoptosis-induced ligand (TRAIL) shows little or no toxicity in most normal cells and preferentially induces apoptosis in a variety of malignant cells. However, patients develop resistance to TRAIL, therefore, sensitizing agents that can sensitize the tumor cells to TRAIL-mediated apoptosis are necessary. In this study, we investigated the effect of 2-(3-hydroxyphenyl)-5-methylnaphthyridin-4-one (CSC-3436), an useful flavonoid, to overcome the TRAIL-resistant triple negative breast cancer (TNBC) cells. We found that CSC-3436 potentiated TRAIL-induced apoptosis in TRAIL-resistant TNBC cells and this correlated with the upregulation of death receptors (DR)-5 and down-regulation of decreased decoy receptor (DcR)-1 expression. When examined for its mechanism, we found that the decreased expression of anti-apoptotic proteins c-FLIPS/L, Bcl-Xl, Bcl-2, Survivin, and XIAP. CSC-3436 would increase the expression of Bax and promoted the cleavage of bid. In addition, the induction of DR5 by CSC-3436 was found to be dependent on the modulation of reactive oxygen species (ROS)/p38/C/EBP-homologous protein (CHOP) signaling pathways. Overall, our results indicated that CSC-3436 could potentiate the apoptotic effects of TRAIL through down-regulation of cell survival proteins and upregulation of DR5 via the ROS-mediated upregulation of CHOP protein.

Bladder cancer is the most common malignancy of the urinary tract and arising from the epithelial lining of the urinary bladder. Resistance to cytotoxic therapies is associated with overexpression of oncogenic proteins; including HER2, and Akt in chemotherapy resistance of bladder cancer. Various studies demonstrated that curcuminoids, the most important active phenolic compounds of turmeric (Curcuma longa), have anti-tumor activities in a wide range of human malignant cell lines. The aim of this study is to evaluate whether curcuminoids (curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin) could repress the expression of HER2 in HER2-overexpressing bladder cancer cells. Among the test compounds, DMC significantly suppressed the expression of HER2, and preferentially inhibited cell proliferation and induced apoptosis in HER2-overexpressing bladder cancer cells. DMC decreases HER2 level through inhibiting the interaction of HER2 and Hsp90. Our study also indicated that DMC showed additive activity in combination with chemotherapeutic agents, including paclitaxel and cisplatin. These findings show that DMC should be developed further as a new antitumor drug candidate for treatment of HER2-overexpressing bladder cancer.

Background/aim Hydrogen peroxide (H2O2) is one of the reactive oxygen species (ROS), which can induce apoptotic cell death in numerous cancer cells. Pterostilbene (PTE), a natural polyphenolic compound, induces cell apoptosis in many human cancer cells. Materials and methods We investigated whether PTE could enhance H2O2-induced cell apoptosis in human keratinocyte HaCaT cells in vitro. The morphological change of HaCaT cells was observed and photographed under a contrast-phase microscope. The percentage of cell viability was measured by propidium iodide exclusion assay. Cell apoptosis was performed by Annexin V/PI double staining and assayed by flow cytometer. DNA condensation was measured by DAPI staining. The protein expression was determined by western blotting. ROS production-associated proteins were also assayed by confocal laser scanning microscopy. Results PTE pre-treatment enhanced H2O2 (600 μM)-induced cell morphological changes and reduced the total cell number (cell viability). The decreased cell viability in HaCaT cells was through induction of apoptotic cell death, which was confirmed by Annexin V/PI double staining and DAPI staining. Western blotting studies indicated that HaCaT cells which were pre-treated with PTE (100 μM) and then co-treated with H2O2 (600 μM) for 12 h showed significantly increased levels of SOD (Cu/Zn), SOD (Mn), Bax, caspase-3, caspase-8, caspase-9, PARP, p53, p-p53, and p-H2A.X but decreased levels Bcl-2 and catalase. Results also showed that HaCaT cells pre-treated with PTE and then co-treated with H2O2 had increased expression of SOD (Cu/Zn) and glutathione but decreased catalase. Conclusion These observations suggest that PTE pre-treatment can enhance the H2O2-induced apoptotic cell death in keratinocyte cells and may be an effective candidate for the treatment of proliferative keratinocytes.

Background Tetrandrine, a bis-benzylisoquinoline alkaloid, induces apoptosis of many types of human cancer cell. Hydrogen peroxide (H2O2) is a reactive oxygen species inducer; however, there are no reports to show whether pre-treatment of tetrandrine with H2O2 induces more cell apoptosis than H2O2 alone. Thus, the present study investigated the effects of tetrandrine on H2O2-induced cell apoptosis of human keratinocytes, HaCaT, in vitro. Materials and methods HaCaT cells were pre-treated with and without tetrandrine for 1 h, and then treated with H2O2 for examining cell morphological changes and cell viability using contrast-phase microscopy and propidium iodide (PI) exclusion assay, respectively. Cells were measured apoptotic cell death by using annexin V/PI double staining and further analyzed by flow cytometer. Cells were further assessed for DNA condensation using 2-(4-amidinophenyl)-6-indolecarbamidine staining. Western blotting was used to measure expression of apoptosis-associated proteins and confocal laser microscopy was used to measure the protein expression and nuclear translocation from the cytoplasm to nuclei. Results Pre-treatment of tetrandrine for 1 h and treatment with H2O2 enhanced H2O2-induced cell morphological changes and reduced cell viability, whilst increasing apoptotic cell death and DNA condensation. Furthermore, tetrandrine significantly increased expression of reactive oxygen species-associated proteins such as superoxide dismutase (Cu/Zn) and superoxide dismutase (Mn) but significantly reduced the level of catalase, which was also confirmed by confocal laser microscopy. It also increased expression of DNA repair-associated proteins ataxia telangiectasia mutated, ataxia-telangectasia and Rad3-related, phospho-P53, P53 and phosphorylated histone H2AX, and of pro-apoptotic proteins BCL2 apoptosis regulator-associated X-protein, caspase-3, caspase-8, caspase-9 and poly ADP ribose polymerase in HaCaT cells. Conclusion These are the first and novel findings showing tetrandrine enhances H2O2-induced apoptotic cell death of HaCaT cells and may provide a potent approach for the treatment of proliferated malignant keratinocytes.

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 (ΔΨm ) 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.

Head and neck squamous cell carcinoma (HNSCC) is a relatively common malignancy, characterized by lethal morbidity. Herein, we attempted to investigate the autophagy/apoptosis activities of the submerged fermented broths of Antrodia salmonea (AS) in HNSCC Twist-overexpressing (OECM-1 and FaDu-Twist) cells. AS (0-150 μg/mL) effectively reduced cell viability, colony formation, and downregulated Twist expression in OECM-1 and FaDu-Twist cells compared to FaDu cells. AS- induced apoptosis was mainly associated with activation of caspase-3, PARP cleavage, increased expression of VDAC-1 and disproportionation of Bax/Bcl-2. Annexin V/PI staining suggested late apoptosis induction by AS treatment. AS exhibits enhanced autophagy process mediated via LC3-I/II accumulation, increased acidic vesicular organelles (AVOs) formation and p62/SQSTM1 expression feeding into the apoptotic program. However, pre-treatment with autophagy blockers 3-MA and CQ significantly diminished AS-induced cell death. Additionally, suppression of AS-induced ROS release by treatment with antioxidant N-acetylcysteine (NAC) resulted in reduction of apoptotic and autophagic cell death. In vivo studies strengthened the above observations and showed that AS effectively reduced the tumor volume and tumor weight in OECM-1-xenografted nude mice. This study discovered that Antrodia salmonea exhibits a novel anti-cancer mechanism which could be harnessed as a new potent drug for HNSCC treatment.

A new efficient Schiff base sensor SB3 for fluorescent and colorimetric “naked-eye” “turn-on” sensing of cyanide anion (CN–) with excellent sensitivity and selectivity was developed. The 4,4'-(perfluoropropane-2,2-diyl)bisphenol group and two phenyl groups were covalently linked by two C = N bonds to extend the conjugation length. The four hydroxyl groups can improve the water solubility of the SB3 sensor. The SB3 sensor exhibited high specificity towards CN− by interrupting its intramolecular charge transfer, resulting in a color change and remarkable “turn-on” green fluorescence emission. The sensing mechanism is caused by the nucleophilic addition of CN– toward imine groups of the SB3 sensor, leading to breaks of the conjugation, fluorescent spectral changes, and color change. It was confirmed by 1H NMR titration and Mass spectra. The detection limits for CN– and Al3+obtained by fluorescence spectrum are 0.80 µM and 0.25 µM, respectively. The SB3 sensor can act as an efficient chemical sensor for detecting the CN– and Al3+ ions under common environmental and physiological conditions (pH 5–12). Besides, the sensor can also detect CN− in food materials (such as sprouting potatoes and cassava flour) and imaging CN− in living cells with strong “turn-on” fluorescence at 490 nm. SB3 is an excellent CN– sensor that exhibits some advantages, including easy synthesis, distinct fluorescence and color change, high selectivity, low detection limit, and good anti-interference ability to analyze solution and food samples, together with fluorescence cell imaging.

Background/aim Our current study aimed to determine the molecular mechanisms of citronellol-induced cell death and ROS accumulation in non-small cell lung cancer (NCI-H1299 cells) and also compare the anticancer effects of citronellol and EOPC. Materials and methods ROS measurement and western blotting were performed to detect whether citronellol can induce necroptosis in vitro. Besides, we performed an in vivo analysis of tumourigenesis inhibition by citronellol treatment in BALB/c (nu/nu) nude mice. Results Necroptosis occured by up-regulating TNF-α, RIP1/RIP3 activities, and down-regulating caspase-3/caspase-8 activities after citronellol treatment in NCI-H1299 cells. Citronellol also resulted in a biphasic increase in ROS production at 1 h and at 12 h in NCI-H1299 cells. Xenograft model experiments showed that citronellol could effectively inhibit subcutaneous tumours produced 4 weeks after intraperitoneal injection of NCI-H1299 in BALB/c nude mice. Conclusion Citronellol induced necroptosis of NCI-H1299 cells via TNF-α pathway and ROS accumulation.

3-O-ethyl ascorbic acid (EAA) is an ether-derivative of ascorbic acid, known to inhibit tyrosinase activity, and is widely used in skincare formulations. Nevertheless, the molecular mechanisms underlying the EAA's effects are poorly understood. Here, the anti-melanogenic activity of EAA was demonstrated through Nrf2-mediated α-MSH inhibition in UVA-irradiated keratinocytes (HaCaT) and autophagy induction and inhibition of α-MSH-stimulated melanogenesis in melanocytes (B16F10). EAA pretreatment increased the HaCaT cell viability but suppressed ROS-mediated p53/POMC/α-MSH pathways in UVA-irradiated cells. Further, the conditioned medium from EAA-pretreated and UVA-irradiated HaCaT cells suppressed the MITF-CREB-tyrosinase pathways leading to the inhibition of melanin synthesis in B16F10 cells. EAA treatment increased nuclear Nrf2 translocation via the p38, PKC, and ROS pathways leading to HO-1, γ-GCLC, and NQO-1 antioxidant expression in HaCaT cells. However, Nrf2 silencing reduced the EAA-mediated anti-melanogenic activity, evidenced by impaired antioxidant gene expression and uncontrolled ROS (H202) generation following UVA irradiation. In B16F10 cells, EAA-induced autophagy was shown by enhanced LC3-II levels, AVO formation, Beclin-1 upregulation, and activation of p62/SQSTM1. Further, EAA-induced anti-melanogenic activity was substantially decreased in autophagy inhibitor (3-MA) pretreated or LC3 knockdown B16F10 cells. Notably, transmission electron microscopy data showed increased melanosome-engulfing autophagosomes in EAA-treated B16F10 cells. Moreover, EAA also down-regulated MC1R, TRP-1/-2, tyrosinase expressions, and melanin synthesis by suppressing the cAMP-CREB-mediated MITF expression in B16F10 cells stimulated with α-MSH. In vivo studies on the zebrafish model further confirmed that EAA inhibited tyrosinase expression/activity and endogenous pigmentation. In conclusion, 3-O-ethyl ascorbic acid is an effective skin-whitening agent and could be used as a topical agent for cosmetic purposes.

Background: Tetrandrine, a bis-benzylisoquinoline alkaloid, induces apoptosis of many types of human cancer cell. Hydrogen peroxide (H(2)O(2)) is a reactive oxygen species inducer; however, there are no reports to show whether pre-treatment of tetrandrine with H(2)O(2) induces more cell apoptosis than H(2)O(2) alone. Thus, the present study investigated the effects of tetrandrine on H(2)O(2)-induced cell apoptosis of human keratinocytes, HaCaT, in vitro. Materials and Methods: HaCaT cells were pre-treated with and without tetrandrine for 1 h, and then treated with H(2)O(2) for examining cell morphological changes and cell viability using contrast-phase microscopy and propidium iodide (PI) exclusion assay, respectively. Cells were measured apoptotic cell death by using annexin V/PI double staining and further analyzed by flow cytometer. Cells were further assessed for DNA condensation using 2-(4-amidinophenyl)-6-indolecarbamidine staining. Western blotting was used to measure expression of apoptosis-associated proteins and confocal laser microscopy was used to measure the protein expression and nuclear translocation from the cytoplasm to nuclei. Results: Pre-treatment of tetrandrine for 1 h and treatment with H(2)O(2) enhanced H(2)O(2)-induced cell morphological changes and reduced cell viability, whilst increasing apoptotic cell death and DNA condensation. Furthermore, tetrandrine significantly increased expression of reactive oxygen species-associated proteins such as superoxide dismutase (Cu/Zn) and superoxide dismutase (Mn) but significantly reduced the level of catalase, which was also confirmed by confocal laser microscopy. It also increased expression of DNA repair-associated proteins ataxia telangiectasia mutated, ataxia-telangectasia and Rad3-related, phospho-P53, P53 and phosphorylated histone H2AX, and of pro-apoptotic proteins BCL2 apoptosis regulator-associated X-protein, caspase-3, caspase-8, caspase-9 and poly ADP ribose polymerase in HaCaT cells. Conclusion: These are the first and novel findings showing tetrandrine enhances H(2)O(2)-induced apoptotic cell death of HaCaT cells and may provide a potent approach for the treatment of proliferated malignant keratinocytes.

Background/Aim: Hydrogen peroxide (H(2)O(2)) is one of the reactive oxygen species (ROS), which can induce apoptotic cell death in numerous cancer cells. Pterostilbene (PTE), a natural polyphenolic compound, induces cell apoptosis in many human cancer cells. Materials and Methods: We investigated whether PTE could enhance H(2)O(2)-induced cell apoptosis in human keratinocyte HaCaT cells in vitro. The morphological change of HaCaT cells was observed and photographed under a contrast-phase microscope. The percentage of cell viability was measured by propidium iodide exclusion assay. Cell apoptosis was performed by Annexin V/PI double staining and assayed by flow cytometer. DNA condensation was measured by DAPI staining. The protein expression was determined by western blotting. ROS production-associated proteins were also assayed by confocal laser scanning microscopy. Results: PTE pre-treatment enhanced H(2)O(2) (600 μM)-induced cell morphological changes and reduced the total cell number (cell viability). The decreased cell viability in HaCaT cells was through induction of apoptotic cell death, which was confirmed by Annexin V/PI double staining and DAPI staining. Western blotting studies indicated that HaCaT cells which were pre-treated with PTE (100 μM) and then co-treated with H(2)O(2) (600 μM) for 12 h showed significantly increased levels of SOD (Cu/Zn), SOD (Mn), Bax, caspase-3, caspase-8, caspase-9, PARP, p53, p-p53, and p-H2A.X but decreased levels Bcl-2 and catalase. Results also showed that HaCaT cells pre-treated with PTE and then co-treated with H(2)O(2) had increased expression of SOD (Cu/Zn) and glutathione but decreased catalase. Conclusion: These observations suggest that PTE pre-treatment can enhance the H(2)O(2)-induced apoptotic cell death in keratinocyte cells and may be an effective candidate for the treatment of proliferative keratinocytes.

Breast cancer is a major public health problem throughout the world. In this report, we investigated whether CHM-1, a novel synthetic antimitotic agent could be developed into a potent antitumor agent for treating human breast cancer. CHM-1 induced growth inhibition in MDA-MB-231, MDA-MB-453 and MCF-7 cells in a concentration-dependent manner. Importantly, CHM-1 is less toxic to normal breast (HBL-100) cells. CHM-1 interacted with tubulin, markedly inhibited tubulin polymerization, and disrupted microtubule organization. Proteins from control and CHM-1-treated animal tumor specimens were analyzed by two-dimensional electrophoresis and MALDI-TOF mass spectrometry. Our results indicated that CHM-1 increased the expression of SIRT2 protein, an NAD-dependent tubulin deacetylase. A prodrug strategy was also investigated to address the problem of low aqueous solubility and low bioavailability of the antitumor agent CHM-1. The water-soluble prodrug of CHM-1 (CHM-1-P) was synthesized. After oral and intravenous administration, CHM-1-P induced a dose-dependent inhibition of tumor growth. The aforementioned excellent anti-tumor activity profiles of CHM-1 and its prodrug CHM-1-P, suggests that CHM-1-P deserves to further develop as a clinical trial candidate for treating human breast carcinoma.

Increasing evidence supports the anti-estrogenic and/or anti-proliferative properties of luteolin, which is a natural flavonoid existing in herbs, vegetables and fruits. However, the molecular mechanisms responsible for these effects are only partially explored. In the present study, estrogen receptor-alpha (ER-α) was identified as a potential molecular target for luteolin. Our data indicated that treatment with luteolin engendered suppression of ER-α protein and mRNA expression in ER-α-positive breast cancer cells. Y-box binding protein-1 (YB-1) is a known transcriptional regulator of ER-α expression. In this studies it was demonstrated that luteolin decreased YB-1 protein and mRNA expression. Integrin-linked kinase (ILK) is able to phosphorylate many downstream effectors that have the potential to regulate YB-1 transcription. We provided evidence for a mechanism by which luteolin suppressed YB-1 expression through the downregulation of ILK/Akt/STAT3-regulated Twist expression in ER-α-positive breast cancer cells. Our data also showed that luteolin inhibited cancer migration and invasion through the inhibition of epithelial-mesenchymal transition (EMT). Taken together, these data indicate that the antitumorigenic effects of luteolin in ER-α-positive breast cancer cells may arise from its ability to reduce ER-α expression.

Tumor necrosis factor-related apoptosis-induced ligand (TRAIL) is nontoxic to normal cells and preferentially cytotoxic to cancer cells. Recent data suggest that malignant breast cancer cells often become resistant to TRAIL. Pterostilbene (PTER), a naturally occurring analogue of resveratrol found in blueberries, is known to induce cancer cells to undergo apoptosis. In the present study, we examined whether PTER affects TRAIL-induced apoptosis and its mechanism in TRAIL-resistant triple negative breast cancer (TNBC) cells. Our data indicated that PTER induced apoptosis (14.68 ± 3.78% for 40 μM PTER vs 1.98 ± 0.25% for control, p < 0.01) in TNBC cells and enhanced TRAIL-induced apoptosis in TRAIL-resistant TNBC cells (18.45 ± 4.65% for 40 μM PTER vs 29.38 ± 6.35% for combination of 40 μM PTER and 100 ng/mL TRAIL, p < 0.01). We demonstrated that PTER induced death receptors DR5 and DR4 as well as decreased decoy receptor DcR-1 and DcR-2 expression. PTER also decreased the antiapoptotic proteins c-FLIPS/L, Bcl-Xl, Bcl-2, survivin, and XIAP. PTER induced the cleavage of bid protein and caused proapoptotic Bax accumulation. Moreover, we found that PTER induced the expression of DR4 and DR5 through the reactive oxygen species (ROS)/ endoplasmic reticulum (ER) stress/ERK 1/2 and p38/C/EBP-homologous protein (CHOP) signaling pathways. Overall, our results showed that PTER potentiated TRAIL-induced apoptosis via ROS-mediated CHOP activation leading to the expression of DR4 and DR5.

Arsenic trioxide (ATO) is clinically used to treat acute promyelocytic leukemia (APL); however, the therapeutic dose of ATO may prompt critical cardiac side effects. Combination therapy may be used to improve the therapeutic efficiency. To evaluate this possibility, the present study determined the combined effects of Hedyotis diffusa Willd (HDW) extract and ATO in leukemic WEHI-3 cells. The results demonstrated that co-treatment of HDW with ATO resulted in a synergistic augmentation of cytotoxicity in cells at the concentration tested. In order to investigate the potential therapeutic application for leukemia, the combined effects of HDW and ATO were analyzed on the WEHI-3 cell-induced orthotopic leukemia animal model in vivo. The WEHI-3 cells in mice with leukemia were established by injecting murine WEHI-3 cells into BALB/c mice, and treating them with HDW and/or combined with ATO. The results indicated that HDW alone or HDW combined with ATO promoted the total survival rate of mice with leukemia, and these effects are dose-dependent. HDW alone or HDW combined with ATO did not affect the body weight, decreased the spleen weight and did not affect the liver weight. Furthermore, the results demonstrated that HDW alone or HDW combined with ATO resulted in a synergistic augmentation of apoptosis in WEHI-3 cells at the concentration tested. In order to further reveal the detailed mechanism of this synergistic effect on apoptosis, apoptosis-related proteins were also evaluated. The data revealed that HDW alone or HDW combined with ATO induced the expression of death receptor 4 (DR4) and DR5 and the activation of poly adenosine diphosphate ribose polymerase, caspase-3, -8 and -9. Furthermore, HDW alone or HDW combined with ATO decreased the expression levels of B-cell lymphoma 2, B-cell lymphoma-extra large and survivin, and increased the expression levels of Bak and t-Bid. Altogether, the results indicate that the combination of HDW with ATO may be a promising strategy used to increase the clinical efficacy of ATO in the treatment of APL.

CWF-145, a synthetic 2-phenyl-4-quinolone derivative exerted potent cytotoxicity against prostate cancer. CWF-145 inhibited prostate cancer cell lines PC-3, DU-145 and LNCap. It had a very low IC50 about 200 nM against castrate-resistant prostate cancer (CRPC) PC-3. We found that CWF-145 had a similar effect to clinical trial antimitotic agents in cancer cells and normal cells. CWF-145 arrested cell cycle at G2/M phase by binding to the β-tubulin at the colchicine-binding site then disrupted microtubule polymerization. Furthermore, the damaged microtubule affected the Akt/mammalian target of rapamycin (mTOR) signaling pathway. Our data showed that CWF-145 activated Akt and mTOR expression to increase emi1 accumulation and inhibit APC. The increased cyclin B1 and securin arrested cell cycle at G2/M phase. Moreover, we showed that Akt activation markedly increased resistance to microtubule-directed agents, including CWF-145, colchicine, and paclitaxel. Interestingly, rapamycin inhibited Akt-mediated therapeutic resistance, indicating that these effects were dependent on mTOR. Taken together, these observations suggest that activation of the Akt/mTOR signaling pathway can promote resistance to chemotherapeutic agents that do not directly target metabolic regulation. These data may provide insight into potentially synergistic combinations of anticancer therapies.

Glioblastoma (GBM) is the most commonly occurring tumor in the cerebral hemispheres. Currently, temozolomide (TMZ), an alkylating agent that induces DNA strand breaks, is considered the frontline chemotherapeutic agent for GBM. Despite its frontline status, GBM patients commonly exhibit resistance to TMZ treatment. We have recently established and characterized TMZ-resistant human glioma cells. The aim of this study is to investigate whether curcumin modulates cell apoptosis through the alternation of the connexin 43 (Cx43) protein level in TMZ-resistant GBM. Overexpression of Cx43, but not ATP-binding cassette transporters (ABC transporters), was observed (approximately 2.2-fold) in TMZ-resistant GBM cells compared to the Cx43 levels in parental GBM cells. Furthermore, at a concentration of 10[Formula: see text][Formula: see text]M, curcumin significantly reduced Cx43 protein expression by about 40%. In addition, curcumin did not affect the expression of other connexins like Cx26 or epithelial-to-mesenchymal transition (EMT) proteins such as [Formula: see text]-catenin or [Formula: see text]E-catenin. Curcumin treatment led to an increase in TMZ-induced cell apoptosis from 4% to 8%. Importantly, it did not affect the mRNA expression level of Cx43. Concomitant treatment with the translation inhibitor cycloheximide (CHX) exerted additional effects on Cx43 degradation. Treatment with the autophagy inhibitor 3-MA (methyladenine) did not affect the curcumin-induced Cx43 degradation. Interestingly, treatment with the proteasome inhibitor MG132 (carbobenzoxy-Leu-Leu-leucinal) significantly negated the curcumin-induced Cx43 degradation, which suggests that curcumin-induced Cx43 degradation occurs through the ubiquitin-proteasome pathway.

// Jui-Wen Ma 1 , Chao-Ming Hung 2, 3 , Ying-Chao Lin 4, 5, 6 , Chi-Tang Ho 7 , Jung-Yie Kao 1 , Tzong-Der Way 8, 9 1 Institute of Biochemistry, College of Life Science, National Chung Hsing University, Taichung, Taiwan 2 Department of General Surgery, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan 3 School of Medicine, I-Shou University, Kaohsiung, Taiwan 4 Division of Neurosurgery, Buddhist Tzu Chi General Hospital, Taichung Branch, Taiwan 5 School of Medicine, Tzu Chi University, Hualien, Taiwan 6 Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan 7 Department of Food Science, Rutgers University, New Brunswick, New Jersey, USA 8 Department of Biological Science and Technology, College of Biopharmaceutical and Food Sciences, China Medical University, Taichung, Taiwan 9 Department of Health and Nutrition Biotechnology, College of Health Science, Asia University, Taichung, Taiwan Correspondence to: Tzong-Der Way, email: tdway@mail.cmu.edu.tw Jung-Yie Kao, email: biosjyk@gmail.com Keywords: HER-2-overexpressing breast cancer cells, aloe-emodin, Y-box binding protein-1, ILK/Akt/mTOR signaling pathway, epithelial-mesenchymal transition Received: January 06, 2016 Accepted: June 12, 2016 Published: July 06, 2016 ABSTRACT Human epidermal growth factor receptor-2 (HER-2)-positive breast cancer tends to be aggressive, highly metastatic, and drug resistant and spreads rapidly. Studies have indicated that emodin inhibits HER-2 expression. This study compared the HER-2-inhibitory effects of two compounds extracted from rhubarb roots: aloe-emodin (AE) and rhein. Our results indicated that AE exerted the most potent inhibitory effect on HER-2 expression. Treatment of HER-2-overexpressing breast cancer cells with AE reduced tumor initiation, cell migration, and cell invasion. AE was able to suppress YB-1 expression, further suppressing downstream HER-2 expression. AE suppressed YB-1 expression through the inhibition of Twist in HER-2-overexpressing breast cancer cells. Our data also found that AE inhibited cancer metastasis and cancer stem cells through the inhibition of EMT. Interestingly, AE suppressed YB-1 expression through the downregulation of the intracellular integrin-linked kinase (ILK)/protein kinase B (Akt)/mTOR signaling pathway in HER-2-overexpressing breast cancer cells. In vivo study showed the positive result of antitumor activity of AE in nude mice injected with human HER-2-overexpressing breast cancer cells. These findings suggest the possible application of AE in the treatment of HER-2-positive breast cancer.

Most studies of tea trees have focused on their ornamental properties, there are fewer published studies on their medical values. The purpose of this study was to compare the chemical constituents and the biological potential of the water extract of leaves in eight species of Camellia including Camellia sinensis. Among eight Camellia species, Camellia sasanqua showed potent anticancer activities in prostate cancer PC3 cells. In addition to catechins, the major component, eugenyl β-primeveroside was detected in C. sasanqua. Eugenyl β-primeveroside blocked the progression of cell cycle at G1 phase by inducing p53 expression and further upregulating p21 expression. Moreover, eugenyl β-primeveroside induced apoptosis in PC3 prostate cancer cells. Our results suggest that C. sasanqua may have anticancer potential.

In our previous study, ursolic acid present in the leaves of Rhododendron formosanum was found to possess antineoplastic activity. We further isolated and unveiled a natural product, cinnamtannin D1 (CNT D1), an A-type procyanidin trimer in R. formosanum also exhibiting anticancer efficacy that induced G1 arrest (83.26 ± 3.11% for 175 μM CNT D1 vs 69.28 ± 1.15% for control, p < 0.01) and autophagy in non-small-cell lung carcinoma (NSCLC) cells. We found that CNT D1-mediated autophagy was via the noncanonical pathway, being beclin-1-independent but Atg5 (autophagy-related genes 5)-dependent. Inhibition of autophagy with a specific inhibitor enhanced cell death, suggesting a cytoprotective function for autophagy in CNT D1-treated NSCLC cells. Moreover, CNT D1 inhibited the Akt/mammalian target of the rapamycin (mTOR) pathway and activated the extracellular signal-regulated kinases 1/2 (ERK1/2) pathway, resulting in induction of autophagy.

Zerumbone, a sesquiterpene compound of edible ginger (Zingiber zerumbet), has been tested for its anti-EMT and anti-metastatic properties in TGF-β1-stimulated human lung cancer (A549) cells. Zerumbone (10/20 µM) treatment prior to TGF-β1-stimulation reversed the adverse morphological changes (fibroblastic-to-epithelial phenotype) and up-regulated the E-cadherin expression against TGF-β1-induced down-regulation. Immunofluorescence and luciferase activity data confirmed the up-regulated E-cadherin expression and transcriptional activity by zerumbone under TGF-β1-stimulation. Further evidence showed that zerumbone decreased TGF-β1-mediated phosphorylation and transcriptional activity of Smad2, but not Smad3. These results revealed that zerumbone inhibits the TGF-β-induced EMT via up-regulation of E-cadherin and down-regulation of Smad2 signalling pathways. Findings from wound-healing, invasion and colony formation experiments proved that zerumbone inhibits TGF-β1-mediated (metastatic) migration, invasion and anchorage-independent growth. Besides, zerumbone alone is capable of inducing autophagy and apoptosis in A549 cells. These results conclude that anti-EMT and anti-metastatic activities of zerumbone may contribute to the development of food-based chemopreventive drugs for non-small cell lung cancer treatment.

This study aims to examine the frictional behavior of staple carbon fiber composites (sCFCs). The staple carbon fiber reinforced polycarbonate (PC) composites were prepared by film stacking for two different impregnation levels. Mechanical properties such as tensile and flexural strengths and moduli and static/dynamic friction coefficient (COF) were determined. The COF and temperature as a function of wearing cycles for sCFCs subjected to different applied pressures were also determined by a disk-on-disk sliding wear test machine. The less impregnated sample exhibited superior tribological performance owing to its rough surface and low frictional heat generation.

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.

We reported in our previously executed studies that the fermented culture broth of Antrodia salmonea (AS), a mushroom used in Taiwanese folk medicine induced reactive oxygen species (ROS)-mediated apoptosis in human ovarian carcinoma cells. In this study, we studied the anticancer efficacies of AS (0-240 μg/ml) by examining the key molecular events implicated in cell death associated with autophagy in SKOV-3 and A2780 human ovarian carcinoma cells and clarified the fundamental molecular mechanisms. Treatment of ovarian carcinoma cells with AS-induced autophagic cell death mediated by increased microtubule-associated protein LC3-II, GFP-LC3 puncta, and acidic vesicular organelle (AVO) formation. These events are linked with the activation of p62/SQSTM1, the inhibition of ATG4B, the expression of ATG7, and the dysregulation of Beclin-1/Bcl-2 (i.e., B-cell lymphoma 2). N-acetylcysteine inhibited AS-induced ROS generation, which in turn constricted AS-induced LC3 conversion, AVO formation, and ATG4B inhibition, indicating ROS-mediated autophagy cell death. In addition, the 3-methyladenine (3-MA) or chloroquine (CQ)-induced autophagy inhibition decreased AS-induced apoptosis. Additionally, apoptosis inhibition by Z-VAD-FMK, a pan-caspase inhibitor, substantially suppressed AS-induced autophagy. Furthermore, AS-inhibited HER-2/ neu and PI3K/AKT signaling pathways which were reversed by autophagy inhibitors 3-MA and CQ. Thus, A. salmonea is a potential chemopreventive agent that is capable of activating ROS-mediated autophagic cell death in ovarian carcinoma cells.

Background/Aim: The banana flower is used for ameliorating urinary disturbance. However, there is limited evidence to support the efficacy or mechanism of action of banana flower against benign prostatic hyperplasia (BPH). In the present study, the anti-BPH activity and mechanisms of banana flower extracts were investigated in vitro and in vivo. Materials and Methods: The banana flower extract is a water-soluble extract obtained by sonication. MTT assay was used to examine whether banana flower extract exhibited cytotoxic effects on BPH-1 cells. The effect of banana flower extract on cell-cycle distribution was examined by flow cytometry. The expression of cell-cycle-regulatory molecules was determined by western blot analysis. Testosterone propionate (TP)-induced rat model of BPH was used to evaluate the anti-BPH activity of banana flower extract in vivo. Results: Banana flower extract reduced epithelial cell line BPH-1 cell viability through cell-cycle arrest at G(1) phase. Moreover, banana flower extract reduced the expression of cyclin D1 and cyclin-dependent kinase 6, while it increased the expression of p53 and p27. Interestingly, banana flower extract suppressed BPH-related inflammatory responses through suppressing cyclo-oxygenase-2 expression and prostaglandin E2 production. Finally, banana flower extract administered orally to male rats reduced prostatic weight and serum dihydrotestosterone level, and improved prostate gland morphology. High-performance liquid chromatography revealed that banana flower extract contains citric acid, taurine, pantothenic acid and nicotinic acid components. In summary, banana flower extract may be used as a therapeutic agent for BPH via anti-proliferative and anti-inflammatory activities.

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.

Antrodia salonea (AS), a fungus that is indigenous to Taiwan has been well known for its anti-cancer properties. We investigated the anti-metastatic and anti-epithelial-mesenchymal transition (EMT) properties of AS in TNBC cells. To determine their EMT and metastasis levels, in vitro wound healing, wound invasion, Western blotting, RT-PCR, luciferase activity and immunofluorescence assays were performed, while the in vivo anti-metastatic efficacy of AS was evaluated in BALB/c-nu mice through bioluminescence imaging, HE staining, and immunohistochemical staining. MDA-MB-231 cells, when treated with AS concentrations (25–100 μg/mL) resulted in significant reduction of invasion and migration as well as the downregulation of VEGF, uPAR, uPA and MMP-9 (inhibition of PI3K/AKT/NFκB pathways). AS treatment prevented morphological changes and reversed EMT through the upregulation of E-cadherin and the downregulation of N-cadherin, Slug, Twist, and Vimentin. Inhibition of Smad3 signaling pathway, downregulation of β-catenin pathway and upregulation of GSK3β expression were also observed while, suppression of metastasis and EMT in TGF-β1-stimulated non-tumorigenic MCF-10A cells was observed when treated with AS. Histological analysis confirmed that AS reduced tumor metastasis and upregulated E-cadherin expression in biopsied lung tissues. Our results indicated that AS exhibits anti-EMT and anti-metastatic activity, that could contribute to develop anticancer drugs against TNBC.

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.

Background/aim The family of matrix metalloproteinases (MMPs) are responsible for the homeostasis of extracellular matrix components and their genetic polymorphisms may be associated with cancer susceptibility. The serum levels of MMP-1 have been reported to be lower in breast cancer patients than healthy subjects. In the current study, we aimed at investigating the contribution of a polymorphism in the promoter region of MMP-1 to breast cancer in Taiwan. Materials and methods The MMP-1 rs1799705 polymorphic genotypes were genotyped among 1,232 breast cancer patients and 1,232 healthy controls by the typical polymerase chain reaction-restriction fragment length polymorphism methodology. Results The percentages of 2G/2G, 1G/2G, and 1G/1G for MMP1 -1607 genotypes were 35.4, 40.6 and 24.0% in the breast cancer group and 34.1, 43.6, and 22.3% in the healthy control group (p trend=0.3025), respectively. The odds ratios (ORs) after adjusting for age, smoking and alcohol drinking status for those carrying 1G/2G and 1G/1G genotypes at MMP1 -1607 were 0.93 (95%CI=0.76-1.11, p=0.2390) and 1.01 (95%CI=0.77-1.23, p=0.7377), respectively, compared to those carrying the wild-type 2G/2G genotype. Supporting this finding, the adjusted OR for those carrying the 1G allele at MMP-1 -1607 was 1.03 (95%CI=0.91-1.18, p=0.8860), compared to those carrying the wild-type 2G allele. Our findings suggest that the polymorphic genotypes at MMP1 promoter -1607 investigated in the current study, may not play a major role in determining cancer susceptibility to breast cancer in Taiwan. Other early diagnostic and predictive markers are urgently needed for personalized and precise breast cancer detection and therapy.

BACKGROUND/AIM Breast tumor interleukin-6 (IL-6) level increases with tumor grade, and elevated serum IL-6 correlates with poor survival in patients with breast cancer. Epithelial-mesenchymal transition (EMT) phenotypes are associated with enhanced metastasis and unfavorable clinical outcome in breast cancer. Therefore, we examined whether IL-6 induced EMT phenotype characterized in breast cancer cells. MATERIALS AND METHODS MCF-7 cells treated with different concentrations (10-50 ng/ml) of IL-6 for 24 and 48 h. Western blotting, flow cytometry, and cell migration assay were used to test whether IL-6 promoted tumor-initiating ability in MCF-7 cells. RESULTS In this study, we found that the induction of EMT by IL-6 resulted in the acquisition of mesenchymal traits and the increase of tumor-initiating ability in MCF-7 cells. Moreover, we found that 2-phenylnaphthy-ridin-4-one derivatives were able to repress IL-6 induced EMT phenotype and tumor-initiating ability. Among these deriveratives, LYF-11 possessed the most potential inhibitory activity. LYF-11 effectively inhibited IL-6-induced EMT phenotype and tumor-initiating ability via the inhibition of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. CONCLUSION Our results suggest a connection between IL-6 receptor activity and EMT phenotype, and tumor-initiating ability. Moreover, LYF-11 is a potential compound for breast cancer therapy by targeting JAK2/STAT3 signaling pathway.

Oral squamous cell carcinoma (OSCC) is a type of cancer with high morbidity and mortality rates worldwide; it also demonstrates chemotherapeutic resistance. Triterpenoid ursolic acid has been shown to exhibit various biological activities and anticancer effects in several preclinical studies. In our previous study, human cisplatin‑resistant oral cancer CAR cells were established, and the present study aimed to further examine the effects of ursolic acid on CAR cells. The results revealed that ursolic acid inhibited CAR cell viability, as determined using a 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide assay. Ursolic acid‑induced cell death was mediated through a caspase‑dependent pathway, determined with the pan‑caspase inhibitor, z‑VAD‑fmk. Ursolic acid also increased the activities of caspase‑3 and caspase‑9 in CAR cells, determined by a colorimetric assay. Specifically, the production of reactive oxygen species and loss of mitochondrial membrane potential, detected by flow cytometry, were observed in the ursolic acid‑treated CAR cells. The apoptosis‑associated signaling showed that ursolic acid decreased the phosphorylation of AKT (Ser473) and B‑cell lymphoma 2 (Bcl‑2)‑associated agonist of cell death (BAD; Ser136), and the protein levels of Bcl‑2 and Bcl‑extra large (Bcl‑xL), and increased the expression of BAD and Bcl‑2‑associated X (Bax) protein in CAR cells. In summary, the results supported the potential application of ursolic acid against drug‑resistant oral carcinoma and to improve oral anticancer efficacy in the near future.

BACKGROUND/AIM The family of matrix metalloproteinases (MMPs) controls homeostasis of the extracellular matrix and their genetic polymorphisms may be associated with personal cancer susceptibility. The serum levels of MMP8 was reported to be higher in patients with breast cancer than in healthy individuals. In this study, we aimed to investigate the contribution of a polymorphism in the promoter region of MMP8 (-799C/T) and two nonsynonymous polymorphisms (Val436Ala and Lys460Thr) to breast cancer. MATERIALS AND METHODS MMP8 -799C/T, Val436Ala and Lys460Thr polymorphic genotypes were determined for 1,232 patients with breast cancer and 1,232 healthy controls by polymerase chain reaction-restriction fragment length polymorphism methodology. RESULTS The odds ratios (ORs) after adjusting for age, gender, smoking and alcohol drinking status for those carrying CT and TT genotypes at the MMP8 promoter C-799T were 1.03 (95% CI=0.88-1.23, p=0.7475) and 1.08 (95% CI=0.91-1.53, p=0.3561), respectively, compared to those carrying the wild-type CC genotype. The OR for the combined T-bearing genotypes were of a similar non-significant level (OR=1.05, 95% CI=0.90-1.26, p=0.5176). Supporting this finding, the adjusted OR for those carrying the T allele at MMP8 C-799T was 1.05 (95% CI=0.86-1.21, p=0.3797), compared to those carrying the wild-type C allele. There was also no significant association of MMP8 Lys460Thr with breast cancer. There was no polymorphic genotype at MMP8 Val436Ala found among any of the investigated individuals. CONCLUSION MMP8 -799C/T, Val436Ala and Lys460Thr polymorphisms may only play an indirect role in determining personal cancer susceptibility to breast cancer in Taiwan.

Breast tumor interleukin-6 (IL-6) level increases with tumor grade, and elevated serum IL-6 correlates with poor survival in patients with breast cancer. Epithelial-mesenchymal transition (EMT) phenotypes are associated with enhanced metastasis and unfavorable clinical outcome in breast cancer. Therefore, we examined whether IL-6 induced EMT phenotype characterized in breast cancer cells.MCF-7 cells treated with different concentrations (10-50 ng/ml) of IL-6 for 24 and 48 h. Western blotting, flow cytometry, and cell migration assay were used to test whether IL-6 promoted tumor-initiating ability in MCF-7 cells.In this study, we found that the induction of EMT by IL-6 resulted in the acquisition of mesenchymal traits and the increase of tumor-initiating ability in MCF-7 cells. Moreover, we found that 2-phenylnaphthy-ridin-4-one derivatives were able to repress IL-6 induced EMT phenotype and tumor-initiating ability. Among these deriveratives, LYF-11 possessed the most potential inhibitory activity. LYF-11 effectively inhibited IL-6-induced EMT phenotype and tumor-initiating ability via the inhibition of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway.Our results suggest a connection between IL-6 receptor activity and EMT phenotype, and tumor-initiating ability. Moreover, LYF-11 is a potential compound for breast cancer therapy by targeting JAK2/STAT3 signaling pathway.

Glioblastoma multiforme (GBM) is the most fatal form of human brain cancer. Although temozolomide (TMZ), an oral alkylating chemotherapeutic agent, improves the survival rate, the prognosis of patients with GBM remains poor. Naturally occurring carbazole alkaloids isolated from curry leaves (Murraya koenigii Spreng.) have been shown to possess a wide range of anticancer properties. However, the effects of carbazole derivatives on glioblastoma cells remain poorly understood. In the present study, anti‑glioblastoma profiles of a series of synthetic carbazole derivatives were evaluated in vitro. The most promising derivative in this series was BC3EE2,9B, which showed significant anti‑proliferative effects in GBM8401 and GBM8901 cells. BC3EE2,9B also triggered cell‑cycle arrest, most prominently at the G1 stage, and suppressed glioblastoma cell invasion and migration. Furthermore, BC3EE2,9B induced autophagy‑mediated cell death and synergistically sensitized GBM cells to TMZ cytotoxicity. The possible mechanism underlying BC3EE2,9B‑induced autophagy may involve activation of adenosine monophosphate-activated protein kinase and the attenuation of the Akt and mammalian target of the rapamycin downstream signaling pathway. Taken together, the present results provide molecular evidence for the mode of action governing the ability of BC3EE2,9B to sensitize drug‑resistant glioblastoma cells to the chemotherapeutic agent TMZ.

γ-Bisabolene, one of main components in cardamom, showed potent in vitro and in vivo anti-proliferative activities against human oral squamous cell carcinoma (OSCC). γ-Bisabolene activated caspases-3/9 and decreased mitochondrial memebrane potential, leading to apoptosis of OSCC cell lines (Ca9-22 and SAS), but not normal oral fibroblast cells. Phosphoproteome profiling of OSCC cells treated with γ-bisabolene was identified using TiO2-PDMS plate and LC-MS/MS, then confirmed using Western blotting and real-time RT-PCR assays. Phosphoproteome profiling revealed that γ-bisabolene increased the phosphorylation of ERK1/2, protein phosphatases 1 (PP1), and p53, as well as decreased the phosphorylation of histone deacetylase 2 (HDAC2) in the process of apoptosis induction. Protein-protein interaction network analysis proposed the involvement of PP1-HDAC2-p53 and ERK1/2-p53 pathways in γ-bisabolene-induced apoptosis. Subsequent assays indicated γ-bisabolene eliciting p53 acetylation that enhanced the expression of p53-regulated apoptotic genes. PP1 inhibitor-2 restored the status of HDAC2 phosphorylation, reducing p53 acetylation and PUMA mRNA expression in γ-bisabolene-treated Ca9-22 and SAS cells. Meanwhile, MEK and ERK inhibitors significantly decreased γ-bisabolene-induced PUMA expression in both cancer cell lines. Notably, the results ascertained the involvement of PP1-HDAC2-p53 and ERK1/2-p53 pathways in mitochondria-mediated apoptosis of γ-bisabolene-treated cells. This study demonstrated γ-bisabolene displaying potent anti-proliferative and apoptosis-inducing activities against OSCC in vitro and in vivo, elucidating molecular mechanisms of γ-bisabolene-induced apoptosis. The novel insight could be useful for developing anti-cancer drugs.

Amplification of the HER2 gene (also known as neu or ErbB2) or overexpression of HER2 protein has become a solicitous therapeutic target in metastatic and clinical drug-resistance cancer. In our present work, a new series of curcumin derivatives were designed and synthesized using curcumin as model. Here, we evaluated whether curcumin derivatives have better efficiency to degrade HER2 than curcumin. Among these test compounds, pculin02H had better efficiency to inhibit the expression of HER2 than curcumin. Moreover, pculin02H preferentially suppressed the growth of HER2-overexpressing cancer cell lines. Pculin02H induced G2/M cell cycle arrest followed by apoptosis. Interestingly, our results suggested that a posttranslational mechanism contributed to pculin02H-induced HER2 depletion in HER2-overexpressing cancer cells. We found that pculin02H significantly enhanced the antitumor efficacy of clinical drugs on HER2-overexpressing cancer cells as well as efficiently reduced HER2-induced drug resistance. These findings may provide an alternative preventive or therapeutic strategy against HER2-overexpressing cancer cells.

Curcuminoids, including curcumin (CUR), demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC), show the maximum absorption wavelength near blue light. Photodynamic therapy (PDT) has been developed as a therapeutic modality, which could induce cell death via the formation of ROS under illumination. Recently, it has been suggested that curcuminoids may be developed as potential photosensitizers. Here we found that curcuminoids-PDT significantly inhibited cell viability in breast cancer cell lines; in particular DMC-PDT has the highest anti-proliferative effect. A comprehensive analysis of cell response to DMC-PDT showed that autophagy was an early event and apoptosis was a late event. The generation of ROS by exciting the photosensitizer in PDT can activate MAPK pathway. Pre-treatment with a singlet oxygen scavenger or JNK inhibitor in DMC-PDT resulted in the reversion of cell viability, a reduced LC3 conversion and PARP cleavage. These results indicate that DMC may be considered as a new photosensitizer in PDT for cancer treatment.