stilbenes and Nasopharyngeal-Neoplasms

Topics: Antigens, CD; Cadherins; Cell Line, Tumor; Cell Movement; Cell Proliferation; Down-Regulation; Epithelial-Mesenchymal Transition; Gene Expression Regulation, Neoplastic; Humans; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Nasopharyngeal Carcinoma; Nasopharyngeal Neoplasms; Proteomics; Stilbenes; Vimentin

Identification of safe, effective radiosensitizing agents is urgently needed to improve the outcome of radiotherapy in nasopharyngeal cancer (NPC). In this study, we assessed the ability of the polyphenol resveratrol to act as a radiosensitizer in vitro and in vivo. CNE-1 cells were treated with 50 µM resveratrol for 24 h, then irradiated. E2F transcription factor 1 (E2F1) was stably knocked down and overexpressed using lentiviruses. A xenograft model of NPC was established in nude mice using CNE-1 cells. Compared to control DMSO‑treated CNE-1 cells, resveratrol inhibited colony-forming ability and induced G1 phase cell cycle arrest. Radiation survival curves confirmed resveratrol significantly sensitized CNE-1 cells, and resveratrol in combination with 2 Gy irradiation synergistically increased apoptosis. Immunoblotting showed resveratrol dose- and time-dependently downregulated E2F1 and phospho-AKT (p-AKT). Knockdown of E2F1 significantly increased radiosensitivity and downregulated p-AKT; overexpression of E2F1 reversed resveratrol-induced radiosensitivity and upregulated p-AKT. In vivo, 50 mg/kg/day resveratrol and 4 Gy irradiation led to significantly lower tumor volume and tumor weight compared to resveratrol or irradiation alone. Our findings show that resveratrol increases the radiosensitivity of NPC cells by downregulating E2F1 and inhibiting p-AKT, and therefore has potential as a radiosensitizer for NPC.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Cycle; Chemoradiotherapy; E2F1 Transcription Factor; Gene Expression Regulation, Neoplastic; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Nasopharyngeal Neoplasms; Proto-Oncogene Proteins c-akt; Radiation Tolerance; Radiation-Sensitizing Agents; Resveratrol; Stilbenes; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Resveratrol, a natural phenolic compound found in red grapes, has been reported to inhibit proliferation and induce apoptosis via regulation of AMPK signaling pathways in several cancer cell types. However, little is known about the effect of resveratrol on the human Nasopharyngeal carcinoma (NPC) cell line C666-1. Moreover, the molecular mechanisms of resveratrol-mediated apoptosis in C666-1 cells remain to be clarified.. Cell proliferation was measured by CCK8 assay, cell apoptosis rate was evaluated by flow cytometric analysis, and the protein expression alterations of AMPK signaling pathways were detected by Western blotting.. Treatment of resveratrol inhibited cell viability and promote apoptosis of C666-1 cells. In addition, we showed that resveratrol could also activate caspase-3 and alter the Bax/Bcl-2 apoptotic signaling. Furthermore, all these changes may be due to the activation of AMPK activity by resveratrol treatment, and we also found that the p70S6K and s6 activities, downstream factors of AMPK, were also blocked by resveratrol.. Our results revealed that resveratrol can be regarded as a new effective and chemopreventive compound for human NPC treatment.

Topics: AMP-Activated Protein Kinases; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Line, Tumor; Cell Proliferation; Cell Survival; Enzyme Activation; Humans; Mechanistic Target of Rapamycin Complex 1; Multiprotein Complexes; Nasopharyngeal Neoplasms; Resveratrol; Stilbenes; TOR Serine-Threonine Kinases

In this study, we designed biodegradable polymersomes for co-delivery of an antiangiogenic drug combretastatin-A4 phosphate (CA4P) and doxorubicin (DOX) to collapse tumor neovasculature and inhibit cancer cell proliferation with the aim to achieve synergistic antitumor effects. The polymersomes co-encapsulating DOX and CA4P (Ps-DOX-CA4P) were prepared by solvent evaporation method using methoxy poly(ethylene glycol)-b-polylactide (mPEG-PLA) block copolymers as drug carriers. The resulting Ps-DOX-CA4P has vesicles shape with uniform sizes of about 50 nm and controlled co-encapsulation ratios of DOX to CA4P. More importantly, Ps-DOX-CA4P (1:10) showed strong synergistic cytotoxicity (combination index CI = 0.31) against human nasopharyngeal epidermal carcinoma (KB) cells. Furthermore, Ps-DOX-CA4P accumulated remarkably in KB tissues xenografts in nude mice. Consistent with these observations, Ps-DOX-CA4P (1:10) achieved significant antitumor potency because of fast tumor vasculature disruption and sustained tumor cells proliferation inhibition in vivo. The overall findings indicate that co-delivery of an antiangiogenic drug and a chemotherapeutic agent in polymersomes is a potentially promising strategy for cancer therapy.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma; Doxorubicin; Drug Carriers; Drug Combinations; Drug Compounding; Drug Synergism; Female; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Nanocapsules; Nasopharyngeal Carcinoma; Nasopharyngeal Neoplasms; Polymers; Stilbenes; Tissue Distribution; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Autophagy and endoplasmic reticulum (ER) stress response is important for cancer cells to maintain malignancy and resistance to therapy. trans-Resveratrol (RSV), a non-flavonoid agent, has been shown to induce apoptosis in human nasopharyngeal carcinoma (NPC) cells. In this study, the involvements of tumor-specific ER stress and autophagy in the RSV-mediated apoptosis were investigated. In addition to traditional autophagosomes, the images of transmission electron microscopy (TEM) indicated that RSV markedly induced larger, crescent-shaped vacuoles with single-layered membranes whose the expanded cisternae contains multi-lamellar membrane structures. Prolonged exposure to RSV induced a massive accumulation of ER expansion. Using an EGFP-LC3B transfection and confocal laser microscopy approach, we found RSV-induced EGFP-LC3 puncta co-localized with ER-tracker red dye, implicating the involvement of LC3II in ER expansion. The proapoptotic effect of RSV was enhanced after suppression of autophagy by ATG7 siRNA or blocking the autophagic flux by bafilomycin A1, but that was not changed after targeted silence of IRE1 or CHOP by siRNA. Using caspase inhibitors, we demonstrated the upregulation of caspase-12 (casp12) and the activation of casp4 were associated with the proapoptotic induction of RSV through the caspase-9/caspase-3 pathway. Intriguingly, siRNA knockdown of casp12, but not caspase-4, decreased the susceptibility of the NPC cells to RSV-mediated apoptosis. Further, we showed that RSV dose-dependently increased the ceramide accumulation as assessed by LC-MS/MS system. Using serine palmitoyltransferase (SPT, a key enzyme of de novo ceramide biosynthesis) inhibitors (L-cycloserine and myriocin), we found the increased ceramide accumulation was strongly correlated with the proapoptotic potential of RSV. This study revealed the ER expansion and upregulation of ER casp12 together may indicate profound biological effects of RSV and contributed to NPC cell death. Targeting the different status of ER stress may provide a possible strategy for cancer treatments.

Topics: Anticarcinogenic Agents; Apoptosis; Autophagy; Carcinoma, Squamous Cell; Caspase 12; Caspases; Caspases, Initiator; Cell Line, Tumor; Ceramides; Endoplasmic Reticulum; Endoplasmic Reticulum Stress; Humans; Nasopharyngeal Neoplasms; Resveratrol; Stilbenes

Resveratrol (trans-3,4',5-trihydroxystilbene) has been shown to exert potent anticancer effects on various types of cancer through its anti-proliferative, anti-angiogenic, antioxidant and pro-apoptotic functions. There is still a lack of experimental evidence regarding whether resveratrol has potential anticancer activity in human nasopharyngeal carcinoma (NPC) cells. The purpose of this study was to explore the anticancer activity of resveratrol in human NPC cells both in vitro and in vivo. Our results indicated that treatment with resveratrol led to a time- and dose-dependent decrease in cell proliferation in NPC cells. A dose-dependent increase in apoptosis in response to resveratrol treatment was also observed in NPC cells. Flow cytometric analysis showed that treatment of NPC cells with resveratrol led to cell cycle arrest at the S and G2/M phases. Mechanistically, resveratrol treatment downregulated the expression of Bcl-2 and hypoxia-inducible factor-1α (HIF-1α) proteins and upregulated the expression of caspase-3 protein. In addition, resveratrol treatment also significantly decreased the phosphorylation levels of Akt1, p70S6K and p-4E-BP-1 and the protein expression of several cyclins involved in cell cycle regulation. In vivo studies further showed that resveratrol was able to significantly inhibit the growth of NPC tumor xenografts in nude mice. Collectively, our findings suggest that resveratrol exerts potent anti-prolife-rative and pro-apoptotic effects on human NPC cells possibly through interfering with the pAkt1/p70S6K signaling pathways, thus it may potentially be developed as an effective agent for chemoprevention and chemotherapy of human NPC.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Carcinoma; Caspase 3; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cyclins; Female; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Mice; Mice, Inbred BALB C; Mice, Nude; Nasopharyngeal Carcinoma; Nasopharyngeal Neoplasms; Neoplasm Transplantation; Phosphorylation; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Resveratrol; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; Stilbenes; Xenograft Model Antitumor Assays

Resveratrol, a naturally occurring dietary compound with chemopreventive properties has been reported to trigger a variety of cancer cell types to apoptosis. Whether resveratrol shows any activity on human nasopharyngeal carcinoma (NPC) cells remained to be determined. The aim of this study was to investigate the effect and mechanism of resveratrol on human NPC cells. Treatment of resveratrol resulted in significant decrease in cell viability of NPC cell lines in a dose- and time-dependent manner. A dose-dependent apoptotic cell death was also measured by flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled resveratrol treatment resulted in a significant loss of mitochondrial transmembrane potential, release of cytochrome c, enhanced expression of Fas ligand (FasL), and suppression of glucose-regulated protein 78 kDa (GRP78). These were followed by activation of caspases-9, -8, -4, and -3, subsequently leading to DNA fragmentation and cell apoptosis. Furthermore, up-regulation of proapoptotic Bax and down-regulation of antiapoptotic Bcl-2 protein were also observed. Taken together, resveratrol induces apoptosis in human NPC cells through regulation of multiple apoptotic pathways, including death receptor, mitochondria, and endoplasmic reticulum (ER) stress. Resveratrol can be developed as an effective compound for human NPC treatment.

Topics: Apoptosis; Carcinoma; Caspases; Cell Line, Tumor; Cell Survival; DNA Fragmentation; Drug Screening Assays, Antitumor; Endoplasmic Reticulum Chaperone BiP; Fas Ligand Protein; Gene Expression Regulation, Neoplastic; Heat-Shock Proteins; Humans; Membrane Potential, Mitochondrial; Models, Biological; Nasopharyngeal Carcinoma; Nasopharyngeal Neoplasms; Proto-Oncogene Proteins c-bcl-2; Resveratrol; Signal Transduction; Stilbenes; Transcription Factor CHOP

Previous studies revealed that polydatin, a natural small compound, possessed protective effect against ischemia/reperfusion injury and inflammation. However, the action and molecular mechanism of its potent anti-cancer activity remain poorly understood. In the present study, polydatin significantly killed several human tumor cell lines in a dose- and time-dependent manner. The compound also dose-dependently caused mitochondrial apoptosis in human nasopharyngeal carcinoma CNE cells. In addition, polydatin triggered endoplasmic reticulum (ER) stress and down-regulated the phosphorylation of Akt in CNE cells, while knock-down of CCAAT/enhancer-binding protein homologous protein (CHOP) dramatically abrogated the inactivation of Akt and reversed the pro-apoptotic effect of polydatin. Furthermore, polydatin provoked the generation of reactive oxygen species in CNE cells, while the antioxidant N-acetyl cysteine almost completely blocked the activation of ER stress and apoptosis, suggesting polydatin-induced reactive oxygen species is an early event that triggers ER stress mitochondrial apoptotic pathways in CNE cells. Taken together, these findings strongly suggest that polydatin might be a promising anti-tumor drug and our data provide the molecular theoretical basis for clinical application of polydatin.

Topics: Apoptosis; Base Sequence; Caspases; Cell Line, Tumor; Cytochromes c; Endoplasmic Reticulum; Glucosides; Humans; Mitochondria; Nasopharyngeal Neoplasms; Phosphorylation; Proto-Oncogene Proteins c-akt; Reactive Oxygen Species; RNA, Small Interfering; Stilbenes; Stress, Physiological

ΔNp63, the N-terminal truncated isoform of p63, has been found to be overexpressed in several human epithelial cancers, including nasopharyngeal carcinomas (NPCs), suggesting a function in carcinogenesis. Trans-resveratrol (RSV) has been shown to exert proapoptotic activities through a p53-dependent or p53-independent pathway in various cancer cells. However, the effects of RSV on NPC are still unexplored. In this study, we investigated the apoptotic effects of RSV on ΔNp63-overexpressing NPC cell lines. We showed that RSV (12-100 μ) induced dose-dependent growth suppression, cell-cycle arrest in the S phase and caspase-dependent apoptosis in NPC-TW076 and NPC-TW039 cells. The RSV effect was accompanied by the downregulation of ΔNp63 and the upregulation of p53 protein in a dose-dependent manner. By using small-interfering RNA (siRNA) technology, we found that the targeted silencing of ΔNp63 induced apoptosis and sensitized the NPC cells to RSV-induced apoptosis through caspase-3 activation, whereas suppression of p53 by siRNA did not inhibit RSV-induced apoptosis. Furthermore, transfection with p53 siRNA or pretreatment with caspase inhibitors (Z-VAD-fmk or Z-DEVD-fmk) had no influence on the RSV downregulation of ΔNp63. Interestingly, ecoptic expression of ΔNp63 did not significantly block RSV-induced cell death and was also downregulated after RSV treatment. Downregulation of ΔNp63 by RSV was shown to occur at the mRNA transcript and post-translational levels. Importantly, RSV enhanced chemotheraptic drug-induced apoptosis in NPC and two human carcinoma cell lines, HT1376 and Hep3B cells. These results suggested that ΔNp63, but not p53, is a molecular target of RSV-induced apoptosis and the regulation of ΔNp63 expression by RSV may provide a therapeutic effect of RSV in human NPC.

Topics: Anticarcinogenic Agents; Apoptosis; Carcinoma; Cell Line, Tumor; Cell Proliferation; Down-Regulation; Humans; Nasopharyngeal Neoplasms; Resveratrol; RNA, Small Interfering; Stilbenes; Trans-Activators; Transcription Factors; Tumor Suppressor Protein p53; Tumor Suppressor Proteins

To explore the sensitization effects of resveratrol on CNE2 nasopharyngeal carcinoma cell line with hypoxia-induced chemotherapy resistance and the potential mechanism.. Human CNE2 nasopharyngeal carcinoma cell line was cultured under hypoxic conditions (37 degrees centigrade, 5% CO(2), 2% O(2)) in vitro. The cultured cells were treated with different concentrations of resveratrol for 48 h. Reversal fold (RF) of reseratrol to chemotherapeutic drugs in CNE2 cells was measured by methyl thiazolyl tetrazolium (MTT) assay. Apoptotic rate of CNE2 cells was observed by flow cytometry. Reverse transcription-polymerase chain reaction (RT-PCR) method and Western blotting were used to investigate the expressions of multidrug resistance gene 1 (mdr1), multidrug resistance-associated protein 1 (MRP1) and hypoxia inducible factor 1alpha (HIF-1alpha) in CNE2 cells.. Resveratrol combined with chemotherapeutics produced a synergistic effect. The RF of 200 micromol/L resveratrol to paclitaxel was 2.58. Combined with paclitaxel, 25, 50, 100 and 200 micromol/L of resveratrol increased the apoptotic rate of CNE2 cells from (22.14+/-1.09)% to (23.24+/-1.37)%, (27.57+/-2.01)%, and (30.36+/-2.31)%, respectively. Resveratrol could down-regulate the expressions of HIF-1alpha, mdr1 and MRP1 significantly. After being treated with resveratrol at different concentrations separately, the expressions of HIF-1alpha, mdr1 and MRP1 in CNE2 cells decreased significantly as compared with paclitaxel alone or paclitaxel plus verapamil (P<0.01).. Resveratrol can enhance the sensitivity of CNE2 cells to chemotherapeutic drugs under hypoxia. The potential mechanism is partly attributed to inhibiting the gene expressions of HIF-1alpha, mdr1 and MRP1.

Topics: Antineoplastic Agents, Phytogenic; Carcinoma; Cell Hypoxia; Cell Line, Tumor; Down-Regulation; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Multidrug Resistance-Associated Proteins; Nasopharyngeal Neoplasms; Paclitaxel; Resveratrol; Stilbenes