Nasopharyngeal Carcinoma Cell CNE2 Research Articles

Grape seed proanthocyanidins induce apoptosis through the mitochondrial pathway in nasopharyngeal carcinoma CNE-2 cells

Although modern radiotherapy offers excellent local control in the treatment of nasopharyngeal carcinoma (NPC), current therapeutic decisions remain burdensome due to the frequency of local recurrence and treatment failure at distant sites. One potential and promising strategy for the prevention or treatment of cancers is the use of bioactive components of plant origin, including dietary plant products. Herein, we studied one class of these bioactive compounds, grape seed proanthocyanidins (GSPs), and explored their effect on NPC CNE-2 cells, as well as the primary mechanism underlying this effect. Our results revealed that treatment of human NPC CNE-2 cells with GSPs reduced cell viability in a dose-and time-dependent manner, and moreover, markedly induced cell cycle arrest at the G2/Mphase, leading to induction of apoptosis. In addition, we found that the underlying mechanism was associated with increased expression of the pro-apoptotic protein Bax, decreased expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL, upregulation of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase (PRAP) protein, and the loss of mitochondrial membrane potential (MMP) (Δψm). Furthermore, GSPs upregulated the Bcl-2 homology3 (BH3)-only proteins, Bim and Bad, in a concentration-dependent manner. Taken together, these data supported our hypothesis that, in human NPCCNE-2 cells, GSPs could induce apoptosis through the mitochondrial pathway and ultimately reduce cell viability. Collectively, the results discussed above provide substantive evidence for the potential of GSPs as an effective bioactive phytochemical for the treatment of NPC.

The Enhancement of Radiation Sensitivity in Nasopharyngeal Carcinoma Cells via Activation of the Rac1/NADPH Signaling Pathway.

We reported in an earlier study that using mass spectrometry and bioinformatic analysis demonstrated Rac1 protein might be mostly mitochondrial target in the radiosensitization process of nasopharyngeal carcinoma CNE-1 cells. The goal of our current study was to reveal the relationship between Rac1/NADPH pathway and radiosensitization in CNE-1 cells using Rac1 activator, phorbol 12-myristate 13-acetate (PMA) and Rac1 inhibitor NSC23766. The Rac1-GTP expression was determined using a pulldown assay, the Rac1 location using a immunofluorescence with a laser scanning confocal microscope, the NADPH oxidase activity with NBT assay and the reactive oxygen species with DCFH-DA probe. The apoptosis rate was analyzed by flow cytometry, and the expressions of p67(phox) and NFκB-p105/p50 were analyzed by Western blot. After treatment with PMA and 2 Gy radiation (compared to the control), Rac1-GTP was activated and translocated to the cell membrane. NADPH oxidase activity, reactive oxygen species of intracellular concentration and the apoptosis rate increased significantly. The expression of p67(phox) and NFκB-p50 protein also increased. However, in the cells treated with NSC23766 alone or NSC23766 combined with 2 Gy irradiation, the results were just the opposite. Overall, these results indicate that the Rac1 protein may be the key target involved in the radiosensitization of nasopharyngeal carcinoma cells. The activated Rac1/NADPH pathway combined with radiation can increase the radiosensitivity of nasopharyngeal carcinoma cells, and the Rac1/NADPH pathway may be the signaling pathway involved in the radiosensitization process.

Morphine, a potential antagonist of cisplatin cytotoxicity, inhibits cisplatin-induced apoptosis and suppression of tumor growth in nasopharyngeal carcinoma xenografts.

Morphine is an opioid analgesic drug often used for pain relief in cancer patients. However, there is growing evidence that morphine may modulate tumor growth, progression and metastasis. In this study, we evaluated whether morphine modulates cisplatin-induced apoptosis in human nasopharyngeal carcinoma CNE-2 cells and whether morphine affects the antitumor activity of cisplatin on tumor growth in human nasopharyngeal carcinoma CNE-2 xenografts in nude mice. We showed that a pretreatment with morphine (1 μg/ml) inhibited the sensitivity of CNE-2 cells to cisplatin by inhibiting cisplatin-induced CNE-2 cell apoptosis, decreasing caspase-3 activity and increasing the Bcl-2/Bax ratio. However, a high dose of morphine (1000 μg/ml) had the opposite effect. We also showed that at a low dose, morphine enhances chemoresistance in an in vivo nasopharyngeal carcinoma (NPC) model by inhibiting cisplatin-induced apoptosis and decreasing neovascularization. Taken together, our results indicate that a low dose of morphine may lead to chemoresistance of cisplatin in NPC models in vitro and in vivo by inhibiting cisplatin-induced apoptosis and decreasing neovascularization.

MicroRNA-200a mediates nasopharyngeal carcinoma cell proliferation through the activation of nuclear factor-κB.

In nasopharyngeal carcinoma (NPC), the nuclear factor-κB (NF-κB) signaling pathway is highly active. The constitutive activation of NF-κB prompts malignant cell proliferation, and microRNAs are considered an important mediator in regulating the NF-κB signaling pathway. The current study investigated the effect of microRNA-200a (miR-200a) on NF-κB activation. Reverse transcription-quantitative polymerase chain reaction was used to quantify the relative level of miR-200a in NPC tissue samples and CNE2 cells. An MTT assay was used to investigate the effect of miR-200a on cell proliferation. To investigate the activation of NF-κB, western blotting was used to measure the protein levels of NF-κB and its downstream targets. To identify the target genes of miR-200a, a luciferase reporter assay was used. The current study demonstrated that miR-200a was upregulated in NPC tissue samples and cell lines. Overexpression of miR-200a resulted in the proliferation of CNE2 cells. Western blot analysis indicated that the protein levels of p65 increased when CNE2 cells were transfected with miR-200a mimics. Additionally, the downstream targets of miR-200a were upregulated, including vascular cell adhesion molecule, intercellular adhesion molecule and monocyte chemoattractant protein-1. The luciferase assay indicated that IκBα was the target gene of miR-200a. In conclusion, miR-200a was demonstrated to enhance NPC cell proliferation by activating the NF-κB signaling pathway.

Effect of silencing HIF-1α by RNA interference on adhesion and invasion of the human nasopharyngeal carcinoma cell line CNE-1

To investigate the effects of HIF-1α on adhesion and invasion of human nasopharyngeal carcinoma CNE-1 cells under hypoxia and underlying molecular mechanisms. CoCl₂was used to mimic tumor hypoxic microenvironment. mRNA and protein expressions of HIF-1α, E-cadherin and CXCR4 in CNE-1 cells at different hypoxic time phases were detected by RT-PCR and ELISA respectively. The influences of silencing HIF-1α using RNA interference on E-cadherin and CXCR4 expressions were evaluated. Adhesion test Transwell invasion test were used to evaluate the effects of HIF-1α gene silencing on cell adhesion and invasion. Under hypoxia, HIF-1α mRNA expression in CNE-1 cells was stable, but its protein expression increased obviously (P<0.05). Both mRNA and protein expressions of E-cadherin were decreased significantly with prolonged hypoxia, while mRNA and protein expressions of CXCR4 increased significantly (P<0.05). After silencing HIF-1α gene, expression of E-cadherin protein was up-regulated, but with down-regulated expression of CXCR4 protein, with a decrease significantly in adhesion rate or invasive cell number of CNE-1 cells (P<0.05). Hypoxia can increase HIF-1α protein expression in nasopharyngeal carcinoma cell line CNE-1. Silencing HIF-1α by RNA interference can reduce inhesion and invasion abilities of CNE-1 cells, which may be mediated by down-regulating E-cadherin expression and up-regulating CXCR4 expression.

A dimeric Phaseolus coccineus lectin with anti-oxidative, anti-proliferative and cytokine-inducing activities

In the present study, a dimeric glucosamine binding lectin, designated as CHL, was purified from Phaseolus coccineus L. var. albonanus Bailey through three chromatographic steps. The molecular weight of CHL was approximately 66kDa. Its hemagglutinating activity toward rabbit erythrocytes was dependent on carbohydrates, especially glucosamine, and was stable at temperatures between 20 and 70°C, and at pH between 1 and 13. Intriguingly, further characterization showed that CHL served as a potent antioxidant to prevent erythrocytes from haemolysis induced by 2′-azobis (2-amidinopropane) dihydrochloride (AAPH) in a dose-dependent manner. Moreover, it exerted antitumor activity against human nasopharyngeal carcinoma CNE1 cells, hepatoma HepG2 cells, and breast cancer MCF7 cells but was devoid of antifungal activity. In addition, the CHL could bring about a significant dose-dependent increase in the production of mRNAs of pro-inflammatory cytokines including interferon-gamma and interleukin-2. These results suggest the potential therapeutic utility of CHL.

Lectin from green speckled lentil seeds (Lens culinaris) triggered apoptosis in nasopharyngeal carcinoma cell lines.

BackgroundThe green speckled lentil seed (Lens culinaris) lectin (GSLL) exhibits hemagglutinating activity, and possesses some properties distinct from those of other lentil lectins (e.g., molecular size, biological activities) that deserve further investigation. This study aims to investigate the basic properties (e.g., molecular size, amino acid sequence, sugar specificity) and biological activities (e.g., antiproliferative activity) of GSLL.MethodsGSLL was purified by successive fractionation on SP-Sepharose, Affi-gel blue gel, Mono Q, and Superdex 75. The biochemical properties of GSLL were investigated by SDS-PAGE, mass spectrometry, N-terminal amino acid sequencing, and sugar inhibition tests. For the biological activities, purified lyophilized GSLL was sterilized, adjusted to concentrations from 1 to 0 mg/mL (by twofold serial dilution) in Dulbecco’s modified Eagle’s medium with fetal bovine serum, and examined by using the MTT assay, flow cytometry, and western blotting after treatment of nasopharyngeal carcinoma CNE1 and CNE2 cell lines with the lectin.ResultsGSLL appeared as a 21-kDa band in non-reducing SDS-PAGE. It was composed of two subunits with molecular sizes of 17 and ~4 kDa. It exhibited specificity in binding to glucose and mannose, as well as glucosides and mannosides. Mass spectrometry and N-terminal amino acid sequencing revealed similarity of GSLL to L. culinaris lectin (LcL), especially higher coverage of the β-chain of LcL. A 48-h treatment with GSLL exerted antiproliferative effects on nasopharyngeal carcinoma CNE1 and CNE2 cell lines with significant inhibition at 0.125 mg/mL (P < 0.001) and 1 mg/mL (P = 0.004), respectively, and these effects were attenuated in the presence of glucose and mannose. GSLL induced apoptosis in nasopharyngeal carcinoma CNE1 cells, with detectable phosphatidylserine externalization, mitochondrial depolarization, and cell cycle arrest. Western blot analysis suggested that GSLL triggered the extrinsic apoptotic pathway involving caspase 3, 8, and 9 in CNE1 cells.ConclusionGSLL possessed some different properties from LcL (e.g., lower pI), and increased caspase 3, 8, and 9 activity in CNE1 cells.

ITRAQ-Based Quantitative Proteomic Analysis of Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC) is a common disease in the southern provinces of China with a poor prognosis. To better understand the pathogenesis of NPC and identify proteins involved in NPC carcinogenesis, we applied iTRAQ coupled with two-dimensional LC-MS/MS to compare the proteome profiles of NPC tissues and the adjacent non-tumor tissues. We identified 54 proteins with differential expression in NPC and the adjacent non-tumor tissues. The differentially expressed proteins were further determined by RT-PCR and Western blot analysis. In addition, the up-regulation of HSPB1, NPM1 and NCL were determined by immunohistochemistry using tissue microarray. Functionally, we found that siRNA mediated knockdown of NPM1 inhibited the migration and invasion of human NPC CNE1 cell line. In summary, this is the first study on proteome analysis of NPC tissues using an iTRAQ method, and we identified many new differentially expressed proteins which are potential targets for the diagnosis and therapy of NPC.

Conjugating an anticancer drug onto thiolated hyaluronic acid by acid liable hydrazone linkage for its gelation and dual stimuli-response release

A prodrug gelation strategy was developed for the sustained and dual stimuli-response release of doxorubicin hydrochloride (DOX·HCl), a commonly used anticancer drug. For this purpose, the chemical conjugation of DOX·HCl onto thiolated hyaluronic acid (HA) was carried out by an acid liable hydrazone linkage and verified by 1H NMR analyses. When exposed to the air, such a polysaccharide conjugate showed unique self-gelation ability in aqueous solution. The gelation time and extent depended mainly on the content of thiol groups on thiolated HA. The resultant hydrogel exhibited a dominant elastic response and a thixotropic property. In particular, it could release sustainably conjugated DOX·HCl in dual pH- and reduction-responsive modes. The cumulative drug release was found to be significantly accelerated under the conditions mimicking the intracellular environments of cancer cells. The in vitro cytotoxicity assays for the human nasopharyngeal carcinoma CNE2 cells treated with various release media confirmed the effectiveness of this conjugate hydrogel for cancer cell inhibition.

Sodium selenite (Na2SeO3) induces apoptosis through the mitochondrial pathway in CNE-2 nasopharyngeal carcinoma cells.

This study investigated the effect of sodium selenite (Na2SeO3) on proliferation, cell cycle, apoptosis as well as the underlying mechanism in CNE-2 nasopharyngeal carcinoma (NPC) cells. The CNE-2 cell line was treated with different concentrations of Na2SeO3, and the effects of Na2SeO3 on cell viability and proliferation were evaluated using Cell Counting kit-8 (CCK-8) assay. Cellular apoptosis and cell cycle were evaluated by flow cytometry following Annexin V‑FITC/PI double staining and PI single staining respectively; nuclei morphology stained with DAPI and Hoechst 333258 was observed under a fluorescence microscope, while DNA fragmentation was detected by agarose gel electrophoresis. The mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) were analyzed using fluorescent staining assays. Expression of Bcl-XL, Bax, Bak, and caspase-3 activation were examined by western blotting. The results showed that Na2SeO3 inhibited proliferation and induced apoptosis of CNE-2 cells in a dose- and time-dependent manner. Na2SeO3 at low concentrations induced cell cycle arrest at S phase, while high concentrations of Na2SeO3 induced cell cycle arrest at G0/G1 phase. Furthermore, Na2SeO3 increased ROS level and decreased MMP, upregulated caspase-3 activity and the expression of Bak and Bax but simultaneously downregulated Bcl-XL. In conclusion, our studies demonstrated that Na2SeO3 had significant anti-proliferative and apoptosis-inducing effects via arresting cell cycle and regulating mitochondria-mediated intrinsic caspase pathway in CNE-2 NPC cells, suggesting that Na2SeO3 might have therapeutic potentials in the treatment of NPC.

Targeting FoxM1 inhibits proliferation, invasion and migration of nasopharyngeal carcinoma through the epithelial‑to-mesenchymal transition pathway.

High expression levels of the forkhead box M1 (FoxM1) transcription factor are associated with metastasis and poor prognosis of malignancies. However, little is known concerning its function in nasopharyngeal carcinoma (NPC). The present study aimed to investigate the impact of FoxM1 inhibition on the migration and invasion of NPC cells and the potential mechanisms. The effects of FoxM1 inhibitor treatment and FoxM1 silencing on the proliferation, migration and invasion of NPC CNE-1 and CNE-2 cells were examined by CCK-8, Transwell migration/invasion and colony formation assays. The effects of stable FoxM1 silencing on the growth and lung metastasis of implanted NPC were evaluated. The relative levels of FoxM1, zinc finger E-box binding homeobox 2 (ZEB2), Snail2 and E-cadherin in the different groups of NPC cells and tumors were determined by quantitative real-time PCR, western blotting and immunohistochemical assays. Treatment with thiostrepton, FoxM1 inhibitor, significantly reduced the survival of NPC cells. Treatment with thiostrepton and/or knockdown of FoxM1 inhibited the anchorage-independent proliferation, migration and invasion of NPC cells. Inhibition of FoxM1 also increased the relative levels of E-cadherin, but reduced ZEB2 and Snail2 expression in NPC cells. Stable FoxM1 silencing inhibited the growth and lung metastasis of implanted NPC in vivo, which was associated with increased levels of E-cadherin, but decreased ZEB2 and Snail2 expression in the NPC tumors. In conclusion, our data clearly indicate that knockdown of FoxM1 inhibited the growth and metastasis of human NPC by modulating epithelial-to-mesenchymal transition (EMT), and FoxM1 may be a potential target for the intervention of NPC.

Identification and analysis of the promoter region of the STGC3 gene.

IntroductionNasopharyngeal carcinoma (NPC) is a common malignant tumor of the head and neck. The STGC3 gene is related to development of nasopharyngeal cancer. The aim of this study is to explore the promoter region of the STGC3 gene.Material and methodsThe bioinformatic technique was applied to predict its promoter region and construct the gene promoter region luciferase for the gene vector and transfection of the human embryonic kidney epithelial 293T cell line, human nasopharyngeal carcinoma CNE2 cell line and immortalized nasopharyngeal epithelial NP69 cell line. The recombinant plasmid pGL3-en283, pGL3-en281, pGL3-en571, empty plasmid pGL3-control, negative control pGL3-enhance and internal control of marine intestine luciferase expression vector pRL-SV40 were transfected into NP69 cells, 293T cells and CNE2 cells. Dual luciferase activity detection showed luciferase luminescence values and marine intestine luciferase luminescence values. Relative luciferase activity (RLA) in each cell was calculated.ResultsWe observed strong promoter activity of plasmid pGL3-en283, pGL3-en281 and pGL3-en571 in NP69, 293T and CNE2 cells compared with the negative control pGL3-enhance plasmid. Among them, pGL3-en281 showed the strongest promoter activity, and these three kinds of recombinant plasmids showed stronger promoter activity in 293T cells than in CNE2 cells.ConclusionsThe pGL3-en281 plasmid showed stronger promoter activity than pGL3-en571 in the three cells, indicating that –11048 bp to –653 bp might be the core promoter region.

Hypofractionated radiotherapy induces miR-34a expression and enhances apoptosis in human nasopharyngeal carcinoma cells.

Nasopharyngeal carcinoma (NPC) is a relatively radiosensitive disease. However, the therapeutic effects of radiotherapy are not always satisfactory due to radioresistance. The hypofractionated schema is currently widely used in clinical practice. In the present study, we investigated the effects of hypofractionated radiotherapy on NPC cells and explored the mechanisms involved. In addition, we aimed to determine the role of miR-34a in the effects of hypofractionated radiotherapy and whether these effects occur in a p53-dependent manner. For this purpose, we used CNE1 and CNE2 NPC cells which were subjected to hyperfractionated and hypofractionated radiotherapy. The viability of the cells was measured by MTT assay and acridine orange (AO) and ethidium bromide (EB) staining was used to observe morphological changes. In addition, AnnexinV-propidium iodide (PI) staining and flow cytometry were used to determine the number of apoptotic cells and mRNA and protein expression was measured by qPCR and western blot analysis, respectively. The results revealed that hypofractionated radiotherapy enhanced apoptosis and increased the expression of miR-34a and p53 in the NPC cells. In addition, it stimulated p53 promoter activity and downregulated the protein expression of c-Myc in the human NPC cells. Furthermore, the knockdown of miR-34a suppressed the growth inhibitory effects induced by hypofractionated radiotherapy. Thus, our results suggest that the enhanced apoptosis of NPC cells may be associated with the miR-34a-mediated suppression of c-Myc in a p53-dependent manner.

Mangiferin induces apoptosis by regulating Bcl-2 and Bax expression in the CNE2 nasopharyngeal carcinoma cell line.

To investigate the anti-proliferative mechanism of mangiferin in a human nasopharyngeal carcinoma cell line, CNE2 cells were incubated with different concentrations of mangiferin (12.5, 25, 50, 100, 150 and 200 μM) or with PBS as a control for 72 hours. Analyses were made of the cell cycle and apoptosis with measurement of mRNA and protein levels of two apoptosis-related genes, Bcl-2 and Bax. Flow cytometry assays showed mangiferin could inhibit CNE2 cell proliferation via G2/M arrest and induction of early apoptosis. Real time PCR and Western blotting showed the mRNA and protein level of Bcl-2 to be down-regulated, while those of Bax were up-regulated, when CNE2 cells were treated with mangiferin. This investigation indicated anti-proliferation effects of mangiferin through induction of cell apoptosis regulated by Bcl-2 and Bax expression.

Functional expression of chloride channels and their roles in the cell cycle and cell proliferation in highly differentiated nasopharyngeal carcinoma cells.

We previously demonstrated that the growth of the poorly differentiated nasopharyngeal carcinoma cells (CNE‐2Z) was more dependent on the activities of volume‐activated chloride channels than that of the normal nasopharyngeal epithelial cells (NP69‐SV40T). However, the activities and roles of such volume‐activated chloride channels in highly differentiated nasopharyngeal carcinoma cells (CNE‐1) are not clarified. In this study, it was found that a volume‐activated chloride current and a regulatory volume decrease (RVD) were induced by 47% hypotonic challenges. The current density and the capacity of RVD in the highly differentiated CNE‐1 cells were lower than those in the poorly differentiated CNE‐2Z cells, and higher than those in the normal cells (NP69‐SV40T). The chloride channel blockers, 5‐nitro‐2‐(3‐phenylpropylamino) benzoic acid (NPPB) and tamoxifen inhibited the current and RVD. Depletion of intracellular Cl− abolished the RVD. The chloride channel blockers reversibly inhibited cell proliferation in a concentration‐ and time‐dependent manner, and arrested cells at the G0/G1 phases, but did not change cell viability. The sensitivity of the three cell lines to the chloride channel blockers was different, with the highest in poorly differentiated cells (CNE‐2Z) and the lowest in the normal cells (NP69‐SV40T). ClC‐3 proteins were expressed in the three cells and distributed inside the cells as well as on the cell membrane. In conclusion, the highly differentiated nasopharyngeal carcinoma CNE‐1 cells functionally expressed the volume‐activated chloride channels, which may play important roles in controlling cell proliferation through modulating the cell cycle, and may be associated with cell differentiation. Chloride channels may be a potential target of anticancer therapy.

Mitochondrial protein targets of radiosensitisation by 1,8-dihydroxy-3-acetyl-6-methyl-9,10 anthraquinone on nasopharyngeal carcinoma cells

In our preliminary study, 1,8-dihydroxy-3-acetyl-6-methyl-9,10 anthraquinone (GXHSWAQ-1), synthesised according to the basic structure of emodin, exhibited a 1.58-fold radiosensitisation on nasopharyngeal carcinoma CNE-1 cells. This study demonstrated that its radiosensitisation activity was achieved by altering the mitochondrial structure: swollen volume, fragmented crista, and decreasing transmembrane potential (P<0.01). Using isobaric tag for relative and absolute quantitation (iTRAQ) technology, 1396 proteins were identified, and the differentially expressed proteins were involved in metabolism, cell proliferation, angiogenesis, DNA repair process according to the biological process clustering results. Bioinformatic analysis showed that CDH1, RAC1, CDC42 proteins might be mostly mitochondrial targets in the radiosensitisation process. Western blotting analyses verified the differential expression of these proteins.

Indole-3-carbinol inhibits nasopharyngeal carcinoma cell growth in vivo and in vitro through inhibition of the PI3K/Akt pathway

Indole-3-carbinol (I3C) is an active component of cruciferous vegetables and has been shown to markedly inhibit the growth of a variety of tumors. However, the role of I3C in nasopharyngeal carcinoma (NPC) remains unclear. Thus, the aim of the present study was to investigate the inhibition of NPC cells by I3C in vitro and in vivo. The human CNE2 NPC cell line was treated with various concentrations (0, 100, 200 and 300 μM) of I3C and analysis of cell proliferation after 0, 24, 48 and 72 h, apoptosis after 48 h and expression levels of phosphatidylinositol 3-kinase (PI3K)/Akt pathway-associated proteins in vitro was performed. BALB/c nude mice were divided into the following groups: Prevention, treatment and control. In vivo, all the nude mice were inoculated with CNE2 NPC cells and the mice in the prevention and treatment groups were administered a diet containing 0.5% I3C prior to and following inoculation, respectively. The tumoricidal effect of I3C was investigated in the nude mice. After eight weeks, the expression levels of PI3K/Akt pathway-associated proteins were analyzed in the tumors from the nude mice in each group. The results demonstrated that with increasing I3C concentrations, cell proliferation decreased and apoptosis increased significantly. In addition, the expression levels of PI3K/Akt pathway-associated proteins decreased. In the animal experiments, the prevention and treatment groups developed smaller tumors and the expression levels of PI3K/Akt pathway-associated proteins were reduced when compared with those in the control group. In addition, very few changes to the heart, liver and kidney tissues were observed with hematoxylin and eosin staining in all the groups. Therefore, the results of the present study indicated that I3C inhibited the growth of NPC cells and induced apoptosis effectively in vivo and in vitro. The underlying mechanism may be that I3C suppresses the PI3K/Akt pathway.

Gene transfection of magnetic nanocomposite loading plasmid modified by folic acid targeted to nasopharyngeal carcinoma

To evaluate the molecular targeting capacity and gene transfection efficiency of magnetic nanocomposite coupling with folic acid (FA) of PEG-PEI (-FA) -Alg-Fe3O4 adsorbing plasmid to folate receptor (FR) positive nasopharyngeal carcinoma (NPC) cell. The phagocytosis of magnetic nanocomposite was examined in FR positive NPC HNE-1 and FR negative NPC CNE-2 cells. Prussian blue staining, transmission electron microscope (TEM) and flow cytometry were employed to analyze its gene transfection efficiency by observing the plasmid expression of green fluorescent protein (GFP) in two cell types. Nude mice with implanted HNE-1 and CNE-2 tumor received a tail vein injection of magnetic nanocomposite. And the phagocytosis of magnetic nanocomposite was observed by magnetic resonance imaging (MRI), iron staining and TEM. HNE-1 cell could effectively ingest magnetic nanocomposite, there was a strong intracellular expression of GFP and the gene transfection efficiency was approximately 40.0% ± 3.0%. However, CNE-2 cell had virtually no uptake of magnetic nanocomposite, there was a weak intracellular expression of GFP and the gene transfection efficiency was approximately 4.5% ± 1.5%. The implanted HNE-1 tumor cell could efficiently swallow magnetic nanocomposite, but there was little phagocytosis of magnetic nanocomposite in implanted CNE-2 tumor cell. The magnetic nanocomposite coupling with FA of PEG-PEI (-FA) -Alg-Fe3O4 adsorbing plasmid has excellent molecular targeting capacity and higher gene transfection efficiency.

Preferential cytotoxicity of the type I ribosome inactivating protein alpha-momorcharin on human nasopharyngeal carcinoma cells under normoxia and hypoxia

All primary nasopharyngeal carcinoma (NPC) tumors contain hypoxic regions which are implicated in decreased local control and increased distant metastases, as well as resistance to chemotherapy in advanced NPC patients. One of the promising therapeutic approaches for NPC is to use drugs that can target hypoxic factors in tumors. In the present investigation, the type I ribosome inactivating protein α-momorcharin (α-MMC), isolated from seeds of the bitter gourd Momordica charantia, reduced cell viability and inhibited clonogenic formation of human NPC CNE2 and HONE1 cells under normoxia and cobalt chloride-induced hypoxia. By comparison, α-MMC exhibited only slight cytotoxicity on human nasopharyngeal epithelial NP69 cells under normoxia. Interestingly, α-MMC suppressed the expression levels of hypoxia-inducible factor 1-alpha (HIF1α) and vascular endothelial growth factor (VEGF) in hypoxic NPC, as well as the growth of human umbilical vein endothelial cells. Further study disclosed that α-MMC targeted endoplasmic reticulum and down-regulated unfolded protein response (UPR) in NPC cells. Moreover, α-MMC induced apoptosis in NPC cells in a dose- and time-dependent manner. It initiated mitochondrial- and death receptor-mediated apoptotic signaling in CNE2 cells, but there was hardly any effect on HONE1 cells. In addition, α-MMC brought about G0/G1 phase cell cycle arrest in CNE2 cells and S phase arrest in HONE1 cells. Collectively, α-MMC preferentially exhibited inhibitory effect on normoxic and hypoxic NPC cells partly by blocking survival signaling (e.g. HIF1α, VEGF and UPR), and triggering apoptotic pathways mediated by mitochondria or death receptor. These observations indicate the potential utility of α-MMC for prophylaxis and therapy of NPC.

Berberine Hydrochloride Impact on Physiological Processes and Modulation of Twist Levels in Nasopharyngeal Carcinoma CNE-1 Cells

The main purpose of this work was to investigate the effect of berberine hydrochloride (BH) on the proliferation, apoptosis, migration, and invasion of CNE-1 nasopharyngeal carcinoma cells. Our results shed light on the functional components of traditional Chinese herbs for potential use in modern medicine. The CNE-1 cell line was treated with different concentrations of BH and effects on cell viability and proliferation were evaluated using the Cell Counting Kit-8 (CCK-8) assay. Anti-migratory and anti-invasive actions of BH were investigated using wound healing assays and the Millicell Hanging cell culture insert system, respectively. Expression of the epithelial-mesenchymal transition (EMT)-related gene twist (Twist) was analyzed by real-time PCR and Western blotting. Apoptosis was estimated with an annexin-V fluorescein (FITC) apoptosis detection kit, as well as with reference to levels of activated caspase-3 of CNE-1 cells before and after treatment with BH utilizing fluorescence spectroscopy. BH was capable of reducing proliferation and viability of CNE-1 cells in a dose- and time-dependent manner, also demonstrating anti-migratory and anti-invasive capacities which correlated with reduction in expression of Twist. Finally, BH was able to induce significant amounts of apoptosis in CNE-1 cells, as demonstrated by an increase in the activity of caspase-3 and in annexin-V staining following treatment. BH extracted from rhizoma coptidis demonstrated an ability to block proliferation, induce apoptosis, and impair the migration and invasion of the CNE-1 cell line Considering these properties, our results suggest that BH could be an important compound for consideration in the treatment of nasopharyngeal carcinoma.