Nasopharyngeal Carcinoma Cells Research Articles

MiR-2110 induced by chemically synthesized cinobufagin functions as a tumor-metastatic suppressor via targeting FGFR1 to reduce PTEN ubiquitination degradation in nasopharyngeal carcinoma.

Tumor cell metastasis is the key cause of death in patients with nasopharyngeal carcinoma (NPC). MiR-2110 was cloned and identified in Epstein-Barr virus (EBV)-positive NPC, but its role is unclear in NPC. In this study, we investigated the effect of miR-2110 on NPC metastasis and its related molecular basis. In addition, we also explored whether miR-2110 can be regulated by cinobufotalin (CB) and participate in the inhibition of CB on NPC metastasis. Bioinformatics, RT-PCR, and in situ hybridization were used to observe the expression of miR-2110 in NPC tissues and cells. Scratch, Boyden, and tail vein metastasis model of nude mouse were used to detect the effect of miR-2110 on NPC metastasis. Western blot, Co-IP, luciferase activity, colocalization of micro confocal and ubiquitination assays were used to identify the molecular mechanism of miR-2110 affecting NPC metastasis. Finally, miR-2110 induced by CB participates in CB-stimulated inhibition of NPC metastasis was explored. The data showed that increased miR-2110 significantly suppresses NPC cell migration, invasion, and metastasis. Suppressing miR-2110 markedly restored NPC cell migration and invasion. Mechanistically, miR-2110 directly targeted FGFR1 and reduced its protein expression. Decreased FGFR1 attenuated its recruitment of NEDD4, which downregulated NEDD4-induced phosphatase and tensin homolog (PTEN) ubiquitination and degradation and further increased PTEN protein stability, thereby inactivating PI3K/AKT-stimulated epithelial-mesenchymal transition signaling and ultimately suppressing NPC metastasis. Interestingly, CB, a potential new inhibitory drug for NPC metastasis, significantly induced miR-2110 expression by suppressing PI3K/AKT/c-Jun-mediated transcription inhibition. Suppression of miR-2110 significantly restored cell migration and invasion in CB-treated NPC cells. Finally, a clinical sample assay indicated that reduced miR-2110 was negatively correlated with NPC lymph node metastasis and positively related to NPC patient survival prognosis. In summary, miR-2110 is a metastatic suppressor involving in CB-induced suppression of NPC metastasis.

Immunohistochemical Expression and Clinical Significance of WWP1 Protein in Nasopharyngeal Cancer.

Nasopharyngeal carcinoma (NPC) is a common malignant tumor of the head and neck. Its pathogenesis is complicated and needs further investigation. The aim of this study was to investigate the expression and clinical significance of WWP1 in NPC. Bioinformatics approaches were used to evaluate the expression and functions of WWP1 in NPC. WWP1 protein expression was then detected by immunohistochemistry on a tissue microarray in an NPC cohort and its association with clinical features and prognosis was determined. In addition, WWP1 expression was knocked down in NPC cells using RNA interference, and their colony formation and invasion abilities were assessed. A total of 25 genes closely related to WWP1, which may be enriched in different pathways, were filtered out. WWP1 expression was significantly higher in NPC cells than in normal controls. High WWP1 expression was correlated with lymph node metastasis, tumor recurrence, clinical stage and poor prognosis. Knockdown of WWP1 resulted in attenuated proliferation and invasion of NPC cells. The results suggest that WWP1 may serve as a novel biomarker and prognostic factor for NPC and a potential therapeutic target worthy of further investigation.

Depletion of SLC7A11 Sensitizes Nasopharyngeal Carcinoma Cells to Ionizing Radiation.

Radiotherapy is the primary treatment choice for Nasopharyngeal Carcinoma (NPC). However, its efficacy is compromised due to radioresistance. Ferroptosis, a novel iron-dependent regulated cell death induced by Ionizing Radiation (IR), plays a role in promoting cancer cell death. Yet, the relationship between enhanced ferroptosis and increased sensitivity of NPC cells to IR remains poorly understood. This study aimed to explore the association between IR and ferroptosis in NPC, as well as the role of the ferroptosis repressor SLC7A11 in IR-treated NPC cells. CNE1 and HNE-2 NPC cells were subjected to IR treatment. We performed qPCR and western blotting to evaluate the expression of ferroptosis-related genes in both control and IR-treated NPC cells. Additionally, we used the MTT assay to measure the viability of these NPC cells. JC-1 and DCFH-DA staining were employed to assess mitochondrial membrane potential and Reactive Oxygen Species (ROS) levels in both control and IR-treated NPC cells. Furthermore, we examined the levels of Fe2+, Malondialdehyde (MDA), reduced Glutathione (GSH), and oxidized glutathione (GSSG) in these cells. Moreover, we depleted SLC7A11 in IR-treated NPC cells to investigate its impact on the ferroptosis of these cells. IR upregulated the expression of ferroptosis-related genes, including SLC7A11, ACSL4, COX2, FTH1, and GPX4, in CNE1 and HNE-2 cells. IR treatment also resulted in decreased cell viability, disrupted mitochondrial membrane potential, increased ROS levels, altered glutathione levels, and elevated Fe2+ levels. Knockdown of SLC7A11 enhanced the sensitivity of NPC cells to IR. IR may induce ferroptosis in NPC cells, and stimulating ferroptosis could potentially serve as a therapeutic strategy to enhance the efficacy of IR in treating NPC patients.

Combining Mefloquine with an Mcl-1 Inhibitor as a Novel Therapeutic Strategy for the Treatment of Nasopharyngeal Carcinoma

Considering the established pharmacokinetics and toxicity profiles, drug repurposing has emerged as an alternative therapeutic approach for treating cancer. Mefloquine has previously demonstrated inhibitory effects on multiple cancer types. This study aims to explore the impact of mefloquine on nasopharyngeal carcinoma (NPC). We found that mefloquine, at pharmacologically achievable concentrations, displayed anti-NPC activity while sparing normal counterparts. Mefloquine inhibits proliferation and induces death by reducing the levels of Cyclin A2, Bcl-2, and Bcl-xL. Intriguingly, we observed an increase in the levels of the anti-apoptotic protein Mcl-1. Mefloquine exerts its effects on NPC cells by inducing lysosomal-mediated ROS production, and the heightened expression of Mcl-1 is a consequence of ROS generation in mefloquine-treated NPC cells. The combination of an Mcl-1 inhibitor with mefloquine synergistically inhibits NPC growth in mice without causing substantial toxicity. These findings demonstrate the effectiveness and limited toxicity of mefloquine as a monotherapy and in combination with an Mcl-1 inhibitor. Our research underscores the promise of the mefloquine and Mcl-1 inhibitor combination as a potential treatment for NPC. Additionally, the elevation of Mcl-1 is a compensatory response in cells exposed to oxidative stress, offering a potential target to overcome resistance induced by pro-oxidant therapies.

Capsaicin enhances cisplatin-induced anti-metastasis of nasopharyngeal carcinoma by inhibiting EMT and ERK signaling via SERPINB2.

Cisplatin (DDP)-based combined chemotherapy or concurrent chemoradiotherapy is the mainstay treatment for advanced-stage nasopharyngeal carcinoma (NPC), but needs improvement due to its severe side effects. Capsaicin (CAP) can enhance the anti-tumor activity of cytotoxic drugs. The aim of this study was to investigate the anti-metastasis activity of CAP in combination with DDP in NPC. Herein, CAP and DDP showed synergistic cytotoxic effects on NPC cells. CAP alone and DDP alone inhibited NPC migration and invasion in vitro and in vivo, and the combination of CAP and DDP had the greatest effect. Moreover, CAP upregulated the mRNA and protein expressions of SERPINB2. Further results showed that both SERPINB2 mRNA and protein expressions were downregulated in NPC cell lines and tissues and SERPINB2 overexpression inhibited NPC migration and invasion in vitro and in vivo, while silencing SERPINB2 acted oppositely. In addition, SERPINB2 was abnormally expressed in head and neck squamous cell carcinoma (HNSC) and other multiple cancers and downregulation of SERPINB2 predicted poor prognosis in HNSC according to the Cancer Genome Atlas (TCGA) database. We further found that SERPINB2 overexpression inhibited epithelial-mesenchymal transition (EMT) and the phosphorylated ERK (p-ERK), and the inhibitory effect was enhanced by CAP and DDP. Altogether, our results suggest that the combined inhibition of CAP and DDP on NPC metastasis may be related to the inhibition of EMT and ERK signals mediated by SERPINB2, and CAP may help to improve the efficacy of DDP in the treatment of NPC and develop new therapeutic approaches.

Flavokawain C inhibits glucose metabolism and tumor angiogenesis in nasopharyngeal carcinoma by targeting the HSP90B1/STAT3/HK2 signaling axis

ObjectiveOver the past decade, heat shock protein 90 (HSP90) inhibitors have emerged as promising anticancer drugs in solid and hematological malignancies. Flavokawain C (FKC) is a naturally occurring chalcone that has been found to exert considerable anti-tumor efficacy by targeting multiple molecular pathways. However, the efficacy of FKC has not been studied in nasopharyngeal carcinoma (NPC). Metabolic abnormalities and uncontrolled angiogenesis are two important features of malignant tumors, and the occurrence of these two events may involve the regulation of HSP90B1. Therefore, this study aimed to explore the effects of FKC on NPC proliferation, glycolysis, and angiogenesis by regulating HSP90B1 and the underlying molecular regulatory mechanisms.MethodsHSP90B1 expression was analyzed in NPC tissues and its relationship with patient’s prognosis was further identified. Afterward, the effects of HSP90B1 on proliferation, apoptosis, glycolysis, and angiogenesis in NPC were studied by loss-of-function assays. Next, the interaction of FKC, HSP90B1, and epidermal growth factor receptor (EGFR) was evaluated. Then, in vitro experiments were designed to analyze the effect of FKC treatment on NPC cells. Finally, in vivo experiments were allowed to investigate whether FKC treatment regulates proliferation, glycolysis, and angiogenesis of NPC cells by HSP90B1/EGFR pathway.ResultsHSP90B1 was highly expressed in NPC tissues and was identified as a poor prognostic factor in NPC. At the same time, knockdown of HSP90B1 can inhibit the proliferation of NPC cells, trigger apoptosis, and reduce glycolysis and angiogenesis. Mechanistically, FKC affects downstream EGFR phosphorylation by regulating HSP90B1, thereby regulating the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway. FKC treatment inhibited the proliferation, glycolysis, and angiogenesis of NPC cells, which was reversed by introducing overexpression of HSP90B1. In addition, FKC can affect NPC tumor growth and metastasis in vivo by regulating the HSP90B1/EGFR pathway.ConclusionCollectively, FKC inhibits glucose metabolism and tumor angiogenesis in NPC by targeting the HSP90B1/EGFR/PI3K/Akt/mTOR signaling axis.

Comparative Proteomics Identified EXOSC1 as a Target Protein of Anticancer Peptide LVTX-8 in Nasopharyngeal Carcinoma Cells.

Nasopharyngeal carcinoma (NPC) is a prevalent malignancy that usually occurs among the nose and throat. Due to mild initial symptoms, most patients are diagnosed in the late stage, and the recurrence rate of tumors is high, resulting in many deaths every year. Traditional radiotherapy and chemotherapy are prone to causing drug resistance and significant side effects. Therefore, searching for new bioactive drugs including anticancer peptides is necessary and urgent. LVTX-8 is a peptide toxin synthesized from the cDNA library of the spider Lycosa vittata, which is consisting of 25 amino acids. In this study, a series of in vitro cell experiments such as cell toxicity, colony formation, and cell migration assays were performed to exam the anticancer activity of LVTX-8 in NPC cells (5-8F and CNE-2). The results suggested that LVTX-8 significantly inhibited cell proliferation and migration of NPC cells. To find the potential molecular targets for the anticancer capability of LVTX-8, high-throughput proteomic and bioinformatics analysis were conducted on NPC cells. The results identified EXOSC1 as a potential target protein with significantly differential expression levels under LVTX-8+/LVTX-8- conditions. The results in this research indicate that spider peptide toxin LVTX-8 exhibits significant anticancer activity in NPC, and EXOSC1 may serve as a target protein for its anticancer activity. These findings provide a reference for the development of new therapeutic drugs for NPC and offer new ideas for the discovery of biomarkers related to NPC diagnosis. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (https://proteomecentral.proteomexchange.org) via the iProX partner repository with the data set identifier PXD050542.

MiR-122-5p regulates erastin-induced ferroptosis via CS in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a tumor that occurs in the nasopharynx. Although advances in detection and treatment have improved the prognosis of NPC the treatment of advanced NPC remains challenging. Here, we explored the effect of microRNA (miR)-122-5p on erastin-induced ferroptosis in NPC cells and the role of ferroptosis in the development of NPC. The effect of miR-122-5p silencing and overexpression and the effect of citrate synthase on erastin-induced lipid peroxidation in NPC cells was analyzed by measuring the amounts of malondialdehyde, Fe2+, glutathione, and reactive oxygen species and the morphological alterations of mitochondria. The malignant biological behavior of NPC cells was examined by cell counting kit-8, EDU, colony formation, Transwell, and wound healing assays. The effects of miR-122-5p on cell proliferation and migration associated with ferroptosis were examined in vivo in a mouse model of NPC generated by subcutaneous injection of NPC cells. We found that erastin induced ferroptosis in NPC cells. miR-122-5p overexpression inhibited CS, thereby promoting erastin-induced ferroptosis in NPC cells and decreasing NPC cell proliferation, migration, and invasion.

Downregulation of KLF5 by EBER1 via the ERK signaling pathway in EBV-positive nasopharyngeal carcinoma cells: implications for latent EBV infection.

Nasopharyngeal carcinoma (NPC) carcinogenesis and malignant transformation are intimately associated with Epstein-Barr virus (EBV) infection. A zinc-fingered transcription factor known as Krüppel-like factor 5 (KLF5) has been shown to be aberrantly expressed in a number of cancer types. However, little is known about the regulatory pathways and roles of KLF5 in EBV-positive NPC. Our study found that KLF5 expression was significantly lower in EBV-positive NPC than in EBV-negative NPC. Further investigation revealed that EBER1, which is encoded by EBV, down-regulates KLF5 via the extracellular signal-regulated kinase (ERK) signalling pathway. This down-regulation of KLF5 by EBER1 contributes to maintaining latent EBV infection in NPC. Furthermore, we uncovered the biological roles of KLF5 in NPC cells. Specifically, KLF5 may influence the cell cycle, prevent apoptosis, and encourage cell migration and proliferation - all of which have a generally pro-cancer impact. In conclusion, these findings offer novel strategies for EBV-positive NPC patients' antitumour treatment.

Nasopharyngeal carcinoma with non-squamous phenotype may be a variant of nasopharyngeal squamous cell carcinoma after inhibition of EGFR/PI3K/AKT/mTOR pathway.

Nasopharyngeal carcinoma (NPC) is a cancerous tumor that develops in the nasopharynx epithelium and typically has squamous differentiation. The squamous phenotype is evident in immunohistochemistry, with diffuse nuclear positivity for p63 and p40. Nonetheless, a few NPCs have been identified by clinicopathological diagnosis that do not exhibit the squamous phenotype; these NPCs are currently referred to as non-squamous immunophenotype nasopharyngeal carcinomas (NSNPCs). In a previous work, we have revealed similarities between the histological appearance, etiology, and gene alterations of NSNPC and conventional NPC. According to ultrastructural findings, NSNPC still falls under the category of non-keratinized squamous cell carcinoma that is undifferentiated. NSNPC has an excellent prognosis and a low level of malignancy, according to a retrospective investigation. Based on prior research, we investigated the molecular mechanism of NSNPC not expressing the squamous phenotype and its biological behavior. IHC was used to determine the expression of EGFR, PI3K, AKT, p-AKT, mTOR, p-mTOR, Notch, STAT3 and p-STAT3 in a total of 20 NSNPC tissue samples and 20 classic NPC tissue samples. We obtained human NPC cell lines (CNE-2,5-8F) and used EGFR overexpression plasmid and shRNAs to transfect them. To find out whether mRNA and proteins were expressed in the cells, we used Western blotting and qRT-PCR. Cell biological behavior was discovered using the CCK-8 assay, cell migration assay, and cell invasion assay. EGFR, PI3K, p-AKT and p-mTOR proteins were lowly expressed in NSNPC tissues by immunohistochemistry, compared with classical NPC. In the classical NPC cell lines CNE-2 and 5-8F, overexpression EGFR can up-regulate the expression of p63 through the PI3K/AKT/mTOR pathway, and promote the proliferation, migration, and invasion of nasopharyngeal carcinoma cells. At the same time, knockout of EGFR can down-regulate p63 expression through the PI3K/AKT/mTOR pathway, and inhibit the proliferation, migration, and invasion of nasopharyngeal carcinoma cells. The lack of p63 expression in NSNPC was linked with the inhibition of the EGFR/PI3K/AKT/mTOR pathway, and NSNPC may be a variant of classical NPC.

Arenobufagin induces cell apoptosis by modulating the cell cycle regulator claspin and the JNK pathway in nasopharyngeal carcinoma cells

ABSTRACT Background The high recurrence rate and incidence of distant metastasis of nasopharyngeal carcinoma (NPC) result in poor prognosis. It is necessary to identify natural compounds that can complement combination radiation therapy. Arenobufagin is commonly used for heart diseases and liver cancer, but its effectiveness in NPC is unclear. Study Design and Methods The effect of arenobufagin-induced apoptosis was measured by a cell viability assay, tumorigenic assay, fluorescence assay, and Western blot assay through NPC-039 and NPC-BM cell lines. The protease array, Western blot assay, and transient transfection were used to investigate the underlying mechanism of arenobufagin-induced apoptosis. An NPC xenograft model was established to explore the antitumor activity of arenobufagin in vivo. Results Our findings indicated that arenobufagin exerted cytotoxic effects on NPC cells, inhibiting proliferation through apoptosis activation. Downregulation of claspin was confirmed in arenobufagin-induced apoptosis. Combined treatment with arenobufagin and mitogen-activated protein kinase inhibitors demonstrated that arenobufagin induced NPC apoptosis through the c-Jun N-terminal kinases (JNK) pathway inhibition. Furthermore, arenobufagin suppressed NPC tumor proliferation in vivo. Conclusion Our results revealed the antitumor effect of arenobufagin in vitro and in vivo. Arenobufagin may have clinical utility in treating NPC due to its suppression of claspin and inhibition of the JNK pathway.

Identification of HLA-A*11:01 and A*02:01-Restricted EBV Peptides Using HLA Peptidomics.

Epstein-Barr Virus (EBV) is closely linked to nasopharyngeal carcinoma (NPC), notably prevalent in southern China. Although type II latency of EBV plays a crucial role in the development of NPC, some lytic genes and intermittent reactivation are also critical for viral propagation and tumor progression. Since T cell-mediated immunity is effective in targeted killing of EBV-positive cells, it is important to identify EBV-derived peptides presented by highly prevalent human leukocyte antigen class I (HLA-I) molecules throughout the EBV life cycle. Here, we constructed an EBV-positive NPC cell model to evaluate the presentation of EBV lytic phase peptides on streptavidin-tagged specific HLA-I molecules. Utilizing a mass spectrometry (LC-MS/MS)-based immunopeptidomic approach, we characterized eleven novel EBV peptides as well as two previously identified peptides. Furthermore, we determined these peptides were immunogenic and could stimulate PBMCs from EBV VCA/NA-IgA positive donors in an NPC endemic southern Chinese population. Overall, this work demonstrates that highly prevalent HLA-I-specific EBV peptides can be captured and functionally presented to elicit immune responses in an in vitro model, which provides insight into the epitopes presented during EBV lytic cycle and reactivation. It expands the range of viral targets for potential NPC early diagnosis and treatment.

PICK1 inhibits the malignancy of nasopharyngeal carcinoma and serves as a novel prognostic marker

Although many important advances have been made in the treatment of nasopharyngeal carcinoma (NPC) in recent years, local recurrence and distant metastasis remain the main factors affecting NPC prognosis. Biomarkers for predicting the prognosis of NPC need to be urgently identified. Here, we used whole-exon sequencing (WES) to determine whether PICK1 mutations are associated with the prognosis of NPC. Functionally, PICK1 inhibits the proliferation and metastasis of NPC cells both in vivo and in vitro. Mechanistically, PICK1 inhibited the expression of proteins related to the Wnt/β-catenin signaling pathway. PICK1 restrained the nuclear accumulation of β-catenin and accelerated the degradation of β-catenin through the ubiquitin-proteasome pathway. The reduced PICK1 levels were significantly associated with poor patient prognosis. Hence, our study findings reveal the mechanism by which PICK1 inactivates the Wnt/β-catenin signaling pathway, thereby inhibiting the progression of NPC. They support PICK1 as a potential tumor suppressor and prognostic marker for NPC.

Activation of the MEK/ERK Pathway Mediates the Inhibitory Effects of Silvestrol on Nasopharyngeal Carcinoma Cells via RAP1A, HK2, and GADD45A.

Nasopharyngeal carcinoma (NPC) is a malignant tumor associated with Epstein-Barr virus (EBV) infection. Chemoradiotherapy is the mainstream treatment for locally advanced NPC, and chemotherapeutic drugs are an indispensable part of NPC treatment. However, the toxic side-effects of chemotherapy drugs limit their therapeutic value, and new chemotherapy drugs are urgently needed for NPC. Silvestrol, an emerging natural plant anticancer molecule, has shown promising antitumor activity in breast cancer, melanoma, liver cancer, and other tumor types by promoting apoptosis in cancer cells to a greater extent than in normal cells. However, the effects of silvestrol on NPC and its possible molecular mechanisms have yet to be fully explored. Cell counting kit-8 (CCK-8), cell scratch, flow cytometry, 5-ethynyl-2'-deoxyuridine (EdU), and Western blot (WB) assays were used to evaluate the effects of silvestrol on the cell viability, cell cycle, apoptosis, and migration of NPC cells. RNA sequencing (RNA-Seq) was used to study the effect of extracellular signal-regulated kinase (ERK) inhibitors on the cell transcriptome, and immunohistochemistry (IHC) to assess protein expression levels in patient specimens. Silvestrol inhibited cell migration and DNA replication of NPC cells, while promoting the expression of cleaved caspase-3, apoptosis, and cell cycle arrest. Furthermore, silvestrol altered the level of ERK phosphorylation. The ERK-targeted inhibitor LY3214996 attenuated silvestrol-mediated inhibition of NPC cell proliferation but not migration. Analysis of RNA-Seq data and WB were used to identify and validate the downstream regulatory targets of silvestrol. Expression of GADD45A, RAP1A, and hexokinase-II (HK2) proteins was inhibited by silvestrol and LY3214996. Finally, IHC revealed that GADD45A, RAP1A, and HK2 protein expression was more abundant in cancer tissues than in non-tumor tissues. Silvestrol inhibits the proliferation of NPC cells by targeting ERK phosphorylation. However, the inhibition of NPC cell migration by silvestrol was independent of the Raf-MEK-ERK pathway. RAP1A, HK2, and GADD45A may be potential targets for the action of silvestrol.

Astaxanthin suppresses the malignant behaviors of nasopharyngeal carcinoma cells by blocking PI3K/AKT and NF-κB pathways via miR-29a-3p

BackgroundAs a natural extraction, astaxanthin is gaining increasing attention because of its safety and anti-tumor properties. It has been reported to participate in the progression of various types of cancer such as gastric cancer and ovarian cancer. Nevertheless, the role of astaxanthin in nasopharyngeal carcinoma (NPC) has not been investigated.ObjectThe study aimed to explore the anticancer mechanism of astaxanthin in regulating NPC cell proliferation, cell cycle progression, apoptosis, migration, and invasion.MethodsHuman NPC cells (C666-1) were treated with different concentrations of astaxanthin (0, 1, 10, 20 mg/mL) followed by detection of cell viability. Then, C666-1 cell proliferation, apoptosis, cell cycle progression, invasion, and migration in response to 10 mg/mL astaxanthin, LY294002 (PI3K/AKT inhibitor) or parthenolide (PTL; NF-κB inhibitor) treatment were measured using cell counting kit-8 assay, colony forming assay, flow cytometry analyses, Transwell assay, and wound healing assay, respectively. Western blotting was performed to quantify protein levels of factors involved in PI3K/AKT and NF-κB signaling pathways, cell cycle phase markers (Cyclin D1, p21) and apoptotic markers (Bcl-2 and Bax).ResultsC666-1 cell proliferation, invasion, and migration were significantly suppressed by astaxanthin while cell apoptosis and cell cycle arrest at G1 phase were effectively enhanced in the context of 10 mg/mL astaxanthin. Protein levels of p-AKT, p-P65 and p-IκB levels were suppressed by astaxanthin treatment. After LY294002 or PTL treatment, the suppressive impact of astaxanthin on C666-1 cell process was strengthened, accompanied by the more obvious decrease in cell activity and cell colony number, more enhanced cell apoptosis and G1 phase arrest, and further inhibited cell migration and invasion. Moreover, the inhibitory effect of astaxanthin on Cyclin D1 and Bcl-2 protein levels as well as the promoting impact of astaxanthin on p21 and Bax were also amplified in combination with LY294002 or PTL treatment.ConclusionsAstaxanthin significantly suppresses NPC cell proliferation, cell cycle arrest, migration, invasion while promoting cell apoptosis by inactivating PI3K/AKT and NF-κB pathways. The study first reveals the anticancer role of astaxanthin in NPC, providing a potential candidate for NPC treatment.

The circadian clock gene BMAL1 increases radiosensitivity in nasopharyngeal carcinoma cell CNE2

ObjectiveTo investigate the involvement of the circadian clock gene BMAL1 in regulating radiosensitivity in nasopharyngeal carcinoma (NPC). MethodsThe regulatory role of BMAL1 in NPC radiotherapy was investigated using 44 NPC cases and the NPC cell line CNE2, which had been genetically modified to either overexpress or silence BMAL1. Infected CNE2 cells were divided into four groups, including those with BMAL1 overexpression and BMAL1 RNA interference (RNAi), as well as their respective control groups. The group responses to different doses of radiotherapy were examined. ResultsThe 5-year survival rates of the BMAL1 overexpression group demonstrated a significant increase compared to those of the low expression group (p < 0.05). Furthermore, the BMAL1 overexpression group exhibited a higher tumor-growth inhibition rate (p < 0.001) and apoptotic rate (p = 0.004) following radiotherapy; a decreased proportion of S-phase cells (p < 0.001) but an increased proportion of G2/M-phase cells (p = 0.001) after 24 h of 8Gy irradiation; reduced number of cell colonies (p = 0.042), and a lower survival score (p = 0.037). ConclusionsOur findings demonstrate a positive correlation between BMAL1 expression and NPC survival, suggesting that BMAL1 promotes NPC radiosensitivity.

KLF5 regulates actin remodeling to enhance the metastasis of nasopharyngeal carcinoma.

Transcription factors (TFs) engage in various cellular essential processes including differentiation, growth and migration. However, the master TF involved in distant metastasis of nasopharyngeal carcinoma (NPC) remains largely unclear. Here we show that KLF5 regulates actin remodeling to enhance NPC metastasis. We analyzed the msVIPER algorithm-generated transcriptional regulatory networks and identified KLF5 as a master TF of metastatic NPC linked to poor clinical outcomes. KLF5 regulates actin remodeling and lamellipodia formation to promote the metastasis of NPC cells in vitro and in vivo. Mechanistically, KLF5 preferentially occupies distal enhancer regions of ACTN4 to activate its transcription, whereby decoding the informative DNA sequences. ACTN4, extensively localized within actin cytoskeleton, facilitates dense and branched actin networks and lamellipodia formation at the cell leading edge, empowering cells to migrate faster. Collectively, our findings reveal that KLF5 controls robust transcription program of ACTN4 to modulate actin remodeling and augment cell motility which enhances NPC metastasis, and provide new potential biomarkers and therapeutic interventions for NPC.

Cancer-associated fibroblasts secrete FGF5 to inhibit ferroptosis to decrease cisplatin sensitivity in nasopharyngeal carcinoma through binding to FGFR2

Cisplatin (DDP)-based chemoradiotherapy is one of the standard treatments for nasopharyngeal carcinoma (NPC). However, the sensitivity and side effects of DDP to patients remain major obstacles for NPC treatment. This research aimed to study DDP sensitivity regulated by cancer-associated fibroblasts (CAFs) through modulating ferroptosis. We demonstrated that DDP triggered ferroptosis in NPC cells, and it inhibited tumor growth via inducing ferroptosis in xenograft model. CAFs secreted high level of FGF5, thus inhibiting DDP-induced ferroptosis in NPC cells. Mechanistically, FGF5 secreted by CAFs directly bound to FGFR2 in NPC cells, leading to the activation of Keap1/Nrf2/HO-1 signaling. Rescued experiments indicated that FGFR2 overexpression inhibited DDP-induced ferroptosis, and CAFs protected against DDP-induced ferroptosis via FGF5/FGFR2 axis in NPC cells. In vivo data further showed the protective effects of FGF5 on DDP-triggered ferroptosis in NPC xenograft model. In conclusion, CAFs inhibited ferroptosis to decrease DDP sensitivity in NPC through secreting FGF5 and activating downstream FGFR2/Nrf2 signaling. The therapeutic strategy targeting FGF5/FGFR2 axis from CAFs might augment DDP sensitivity, thus decreasing the side effects of DDP in NPC treatment.

Circular RNA COL1A1 promotes Warburg effect and tumor growth in nasopharyngeal carcinoma

ObjectiveCircular RNAs (circRNAs), pivotal in the pathogenesis and progression of nasopharyngeal carcinoma (NPC), remain a significant point of investigation for potential therapeutic interventions. Our research was driven by the objective to decipher the roles and underlying mechanisms of hsa_circ_0044569 (circCOL1A1) in governing the malignant phenotypes and the Warburg effect in NPC.MethodsWe systematically collected samples from NPC tissues and normal nasopharyngeal epithelial counterparts. The expression levels of circCOL1A1, microRNA-370-5p (miR-370-5p), and prothymosin alpha (PTMA) were quantitatively determined using quantitative polymerase chain reaction (qPCR) and Western blotting. Transfections in NPC cell lines were conducted using small interfering RNAs (siRNAs) or vectors carrying the pcDNA 3.1 construct for overexpression studies. We interrogated the circCOL1A1/miR-370-5p/PTMA axis's role in cellular functions through a series of assays: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide for cell viability, colony formation for growth, Transwell assays for migration and invasion, and Western blotting for protein expression profiling. To elucidate the molecular interactions, we employed luciferase reporter assays and RNA immunoprecipitation techniques.ResultsOur investigations revealed that circCOL1A1 was a stable circRNA, highly expressed in both NPC tissues and derived cell lines. A correlation analysis with clinical pathological features demonstrated a significant association between circCOL1A1 expression, lymph node metastasis, and the tumor node metastasis staging system of NPC. Functionally, silencing circCOL1A1 led to substantial suppression of cell proliferation, migration, invasion, and metabolic alterations characteristic of the Warburg effect in NPC cells. At the molecular level, circCOL1A1 appeared to modulate PTMA expression by acting as a competitive endogenous RNA or 'sponge' for miR-370-5p, which in turn promoted the malignant characteristics of NPC cells.ConclusionTo conclude, our findings delineate that circCOL1A1 exerts its oncogenic influence in NPC through the modulation of the miR-370-5p/PTMA signaling axis.

Near-infrared-triggered Dibenzo[a,c][1,2,5]thiadiazolo[3,4-i]phenazine heterocyclic derivatives for type-I photodynamic and photothermal therapy against human nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) remains endemic in southern China. The general therapeutic consensus is to treat the disease with radiotherapy alone or together with concurrent chemotherapy. But the treatment outcome of NPC remains disappointing with bad prognoses, low overall survival rate and severe side effects. Phototherapy can be a promising approach for treating NPC due to its excellent spatiotemporal selectivity, negligible drug resistance and minimal invasiveness. In this work, two photosensitizers (DTP-Ph and DTP-Et) with similar donor-acceptor structure were designed and constructed for the treatment of NPC. Remarkably, DTP-Ph and DTP-Et show different photo-physicochemical properties as well as mechanisms of phototherapeutic actions, especially DTP-Ph, which exhibits synergistic type-I photodynamic therapy (PDT) and photothermal therapy (PTT) effect under near-infrared (NIR) activation. DTP-Et and DTP-Ph were further encapsulated with F127 to obtain nanoparticles with good water solubility. In intro and in vivo phototherapy evaluations of DTP-Ph NPs display promising phototherapeutic activity with low IC50 value and good tumor growth inhibition (TGI) against human nasopharyngeal carcinoma cell line CNE2 and tumor-bearing xenograft model.