Nuclear factor-kappaB activation mediates cellular transformation, proliferation, invasion angiogenesis and metastasis of cancer

The Recent Research Progress of NF-κB Signaling on the Proliferation, Migration, Invasion, Immune Escape and Drug Resistance of Glioblastoma

Glioblastoma multiforme (GBM) is the most common and invasive primary central nervous system tumor in humans, accounting for approximately 45-50% of all primary brain tumors. How to conduct early diagnosis, targeted intervention, and prognostic evaluation of GBM, in order to improve the survival rate of glioblastoma patients, has always been an urgent clinical problem to be solved. Therefore, a deeper understanding of the molecular mechanisms underlying the occurrence and development of GBM is also needed. Like many other cancers, NF-κB signaling plays a crucial role in tumor growth and therapeutic resistance in GBM. However, the molecular mechanism underlying the high activity of NF-κB in GBM remains to be elucidated. This review aims to identify and summarize the NF-κB signaling involved in the recent pathogenesis of GBM, as well as basic therapy for GBM via NF-κB signaling.

Classical Hodgkin Lymphoma: From Past to Future-A Comprehensive Review of Pathophysiology and Therapeutic Advances

Hodgkin lymphoma, a hematological malignancy of lymphoid origin that typically arises from germinal-center B cells, has an excellent overall prognosis. However, the treatment of patients who relapse or develop resistant disease still poses a substantial clinical and research challenge, even though current risk-adapted and response-based treatment techniques produce overall survival rates of over 95%. The appearance of late malignancies after the successful cure of primary or relapsed disease continues to be a major concern, mostly because of high survival rates. Particularly in pediatric HL patients, the chance of developing secondary leukemia is manifold compared to that in the general pediatric population, and the prognosis for patients with secondary leukemia is much worse than that for patients with other hematological malignancies. Therefore, it is crucial to develop clinically useful biomarkers to stratify patients according to their risk of late malignancies and determine which require intense treatment regimens to maintain the ideal balance between maximizing survival rates and avoiding late consequences. In this article, we review HL's epidemiology, risk factors, staging, molecular and genetic biomarkers, and treatments for children and adults, as well as treatment-related adverse events and the late development of secondary malignancies in patients with the disease.

α-Hederin Saponin Augments the Chemopreventive Effect of Cisplatin against Ehrlich Tumors and Bioinformatic Approach Identifying the Role of SDF1/CXCR4/p-AKT-1/NFκB Signaling

Stromal cell-derived factor-1 (SDF1) and its C-X-C chemokine receptor type 4 receptor (CXCR4) are significant mediators for cancer cells’ proliferation, and we studied their expression in Ehrlich solid tumors (ESTs) grown in mice. α-Hederin is a pentacyclic triterpenoid saponin found in Hedera or Nigella species with biological activity that involves suppression of growth of breast cancer cell lines. The aim of this study was to explore the chemopreventive activity of α-hederin with/without cisplatin; this was achieved by measuring the reduction in tumor masses and the downregulation in SDF1/CXCR4/pAKT signaling proteins and nuclear factor kappa B (NFκB). Ehrlich carcinoma cells were injected in four groups of Swiss albino female mice (Group1: EST control group, Group2: EST + α-hederin group, Group3: EST + cisplatin group, and Group4: EST+α-hederin/cisplatin treated group). Tumors were dissected and weighed, one EST was processed for histopathological staining with hematoxylin and eosin (HE), and the second MC was frozen and processed for estimation of signaling proteins. Computational analysis for these target proteins interactions showed direct-ordered interactions. The dissected solid tumors revealed decreases in tumor masses (~21%) and diminished viable tumor regions with significant necrotic surrounds, particularly with the combination regimens. Immunohistochemistry showed reductions (~50%) in intratumoral NFκβ in the mouse group that received the combination therapy. The combination treatment lowered the SDF1/CXCR4/p-AKT proteins in ESTs compared to the control. In conclusion, α-hederin augmented the chemotherapeutic potential of cisplatin against ESTs; this effect was at least partly mediated through suppressing the chemokine SDF1/CXCR4/p-AKT/NFκB signaling. Further studies are recommended to verify the chemotherapeutic potential of α-hederin in other breast cancer models.

Immunomodulatory Therapy in Head and Neck Squamous Cell Carcinoma: Recent Advances and Clinical Prospects

The immune system plays a significant role in the development, invasion, progression, and metastasis of head and neck cancer. Over the last decade, the emergence of immunotherapy has irreversibly altered the paradigm of cancer treatment. The current treatment modalities for head and neck squamous cell carcinoma (HNSCC) include surgery, radiotherapy, and adjuvant or neoadjuvant chemotherapy which has failed to provide satisfactory clinical outcomes. To encounter this, there is a need for a novel or targeted therapy such as immunological targets along with conventional treatment strategy for optimal therapeutic outcomes. The immune system can contribute to promoting metastasis, angiogenesis, and growth by exploiting the tumor's influence on the microenvironment. Immunological targets have been found effective in recent clinical studies and have shown promising results. This review outlines the important immunological targets and the medications acting on them that have already been explored, are currently under clinical trials and are further being targeted.

Nanoparticle-based drug delivery systems in cancer: A focus on inflammatory pathways

It has become necessary to accept the clinical reality of therapeutic agents targeting the cancer-associated immune system. In recent decades, several investigations have highlighted the role of inflammation in cancer development. It has now been recognized that inflammatory cells secrete mediators, including enzymes, chemokines, and cytokines. These secreted substances produce an inflammatory microenvironment that is critically involved in cancer growth. Inflammation may enhance genomic instability leading to DNA damage, activation of oncogenes, or compromised tumor suppressor activity, all of which may promote various phases of carcinogenesis. Conventional cancer treatment includes surgery, radiation, and chemotherapy. However, treatment failure occurs because current strategies are unable to achieve complete local control due to metastasis. Nanoparticles (NPs) are a broad spectrum of drug carriers typically below the size of 100 nm, targeting tumor sites while reducing off-target consequences. More importantly, NPs can stimulate innate and adaptive immune systems in the tumor microenvironment (TME); hence, they induce a cancer-fighting immune response. Strikingly, targeting cancer cells with NPs helps eliminate drug resistance and tumor recurrence, as well as prevents inflammation. Throughout this review, we provide recent data on the role of inflammation in cancer and explore nano-therapeutic initiatives to target significant mediators, for example, nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), and interleukins (ILs) associated with cancer-related inflammation, to escort the immunomodulators to cancer cells and associated systemic compartments. We also highlight the necessity of better identifying inflammatory pathways in cancer pathophysiology to develop effective treatment plans.

Dibenzoylmethane derivative inhibits melanoma cancer in vitro and in vivo through induction of intrinsic and extrinsic apoptotic pathways

Malignant melanoma has a low incidence, but is the most lethal type of skin cancer. Studies have shown that dibenzoylmethanes (DBMs) have interesting biological activities, including antineoplastic properties. These findings led us to investigate whether news DBM derivatives exert antitumor effects against skin cancers. In a previous study, we found that 1,3-diphenyl-2-benzyl-1,3-propanedione (DPBP) has high in vitro antineoplastic activity against murine B16F10 melanoma cells, with an IC50 of 6.25 μg/mL. In the current study, we used transdermal and topical formulations of DPBP to evaluate its activity and molecular mechanism of action in a murine model of melanoma. The compound induces tumor cell death with high selectivity (selectivity index of 41.94) by triggering apoptosis through intrinsic and extrinsic pathways. DPBP treatment reduced tumor volume as well as serum VEGF-A and uric acid levels. Hepatomegaly and nephrotoxicity were not observed at the tested doses. Histopathological analysis of sentinel lymph nodes revealed no evidence of metastases. According to the observed data, the DPBP compound was effective for the topical treatment of melanoma cancer, suggesting that it acts as a chemotherapeutic or chemopreventive agent.

Exploring the extensive crosstalk between the antagonistic cytokines- TGF-β and TNF-α in regulating cancer pathogenesis

A plethora of cytokines are produced in the tumor microenvironment (TME) those play a vital role in cancer prognosis. Though it is completely contextual, cytokines produced from an inflammatory micro-environment can either modulate cancer progression at early stages of tumor development or in later stages cytokine derived cues can in turn control tumor cell invasion and metastasis. Therefore, understanding the crosstalk between the key cytokines regulating cancer prognosis is critical for the development of an effective therapy. In this regard, the role of transforming growth factor-beta (TGF-β) in cancer is controversially discussed in general inhibition of TGF-β promotes de novo tumorigenesis whereas paradoxically, TGF-β can promote malignancy in already established tumors. Another important cytokine, TNF-α have intense crosstalk with TGF-β from the fact that in a non-cancer context, TGF-β promotes fibrosis whereas TNF-α has anti-fibrotic activity. We have recently reported that TGF-β-induced differentiation of epithelial cells to mesenchymal type is suppressed by TNF-α through regulation of cellular homeostatic machinery- autophagy. Moreover, there are also rare reports of synergy between these two cytokines as well. The crosstalk between TGF-β and TNF-α is not only limited to regulating cancer cell differentiation and proliferation but also includes involvement in cell death. In this review, we hence summarize the molecular mechanisms by which these two important cytokines, TGF-β and TNF-α control cancer prognosis.

Twist2 is NFkB-responsive when p120-catenin is inactivated and EGFR is overexpressed in esophageal keratinocytes

Esophageal squamous cell carcinoma (ESCC) is among the most aggressive and fatal cancer types. ESCC classically progresses rapidly and frequently causes mortality in four out of five patients within two years of diagnosis. Yet, little is known about the mechanisms that make ESCC so aggressive. In a previous study we demonstrated that p120-catenin (p120ctn) and EGFR, two genes associated with poor prognosis in ESCC, work together to cause invasion. Specifically, inactivation of p120ctn combined with overexpression of EGFR induces a signaling cascade that leads to hyperactivation of NFkB and a resultant aggressive cell type. The purpose of this present study was to identify targets that are responsive to NFkB when p120ctn and EGFR are modified. Using human esophageal keratinocytes, we have identified Twist2 as an NFkB-responsive gene. Interestingly, we found that when NFkB is hyperactivated in cells with EGFR overexpression and p120ctn inactivation, Twist2 is significantly upregulated. Inhibition of NFkB activity results in nearly complete loss of Twist2 expression, suggesting that this potential EMT-inducing gene, is a responsive target of NFkB. There exists a paucity of research on Twist2 in any cancer type; as such, these findings are important in ESCC as well as in other cancer types.

Loss of p120ctn causes EGFR-targeted therapy resistance and failure

Epidermal growth factor receptor (EGFR) plays a vital role in cell division and survival signaling pathways. EGFR is activated in nearly every cancer type, and its high expression in tumors is correlated with poor patient outcome. Altogether, EGFR is a prime candidate as a therapeutic target. While targeted EGFR therapy is initially effective in 75% of patients, a majority of patients relapse within the first year due to poorly understood mechanisms of resistance. p120-catenin (p120ctn) has recently been implicated as a biomarker for EGFR therapy. In previous studies, we demonstrated that p120ctn is a tumor suppressor and its loss is capable of inducing cancer. Furthermore, p120ctn down-regulation synergizes with EGFR overexpression to cause a highly invasive cell phenotype. The purpose of this present study was to investigate whether p120ctn down-regulation induced EGFR therapeutic resistance. Using human esophageal keratinocytes, we have found that EGFR-targeting compounds are toxic to cells overexpressing EGFR. Interestingly, these therapies do not cause toxicity in cells with EGFR overexpression and decreased p120ctn expression. These data suggest that decreased p120ctn causes resistance to EGFR therapy. We believe these findings are of utmost importance, as there is an unmet need to discover mechanisms of EGFR resistance.

Evidence that TNF-β induces proliferation in colorectal cancer cells and resveratrol can down-modulate it

IMPACT STATEMENT

The mechanism by which natural products such as resveratrol suppresses TNF-β-promoted tumor cell proliferation, invasion, and colony formation is unknown. In this study, we explored for the first time the effect of resveratrol on the proinflammatory cytokine TNF-β-, compared to TNF-α-stimulated proliferative and pro-inflammatory signaling in HCT116 cells. Our findings suggest that expression of TNF-β and TNF-β-receptor, like TNF-α, can lead to activation of inflammatory transcription factor (NF-κB) and NF-κB-regulated gene biomarkers, which are involved in the promotion of cancer proliferation, invasion, metastasis, and cell survival of tumor. Resveratrol can block TNF-β/TNF-β-receptor-induced activation of NF-κB, NF-κB-modulated gene products, and inhibition of caspase-3 cleavage. These results highlight the therapeutic effect of resveratrol-mediated anti-tumor activity by multitargeting cellular signaling pathways.

Effects of saponins of patrinia villosa against invasion and metastasis in colorectal cancer cell through NF-κB signaling pathway and EMT

BACKGROUND

Research has indicated that Herba Patriniae can suppress the growth of Several kinds of tumor cells in vitro and in vivo, thus displaying favorable antitumor activity. However, research regarding the effect of saponins of Patrinia villosa against CRC cell has not been reported. In the current study, We have revealed that the effects of saponins of patrinia villosa on colorectal cancer (CRC) cell invasion and epithelial-mesenchymal transition (EMT) as well as its underlying mechanism.

METHODS

The CRC EMT model was induced through repeated TGF-β1 stimulations on human CRC cell line SW480. Effects of saponins of patrinia villosa at various concentrations on CRC SW480 cell and EMT model cell proliferation were detected using MTT method, so as to select the optimal action concentration. Meanwhile, effects on SW480 cell and EMT model cell invasion were determined through Scratch assay and Transwell assay. Moreover, changes in expression of EMT-related proteins E-cadherin, N-cadherin and NF-ΚBp65 in each group were detected through Western blotting.

RESULTS

Saponins of patrinia villosa at various concentrations could markedly inhibit the proliferation rate of CRC cell in an obvious concentration-dependent manner. Meanwhile, saponins of patrinia villosa at various concentrations could also remarkably suppress migration of cell developing EMT. In addition, the protein expression of E-cadherin and N-cadherin was down-regulated with the increase in saponins of patrinia villosa concentration, while that of NF-KBp65 was notably down-regulated.

CONCLUSION

Saponins of patrinia villosa can act against tumor invasion and metastasis through inhibiting EMT in human CRC cell line, which may be achieved through down-regulating the NF-κB signaling pathway.

Astragalin-induced cell death is caspase-dependent and enhances the susceptibility of lung cancer cells to tumor necrosis factor by inhibiting the NF-кB pathway

Flavonoids are naturally occurring polyphenolic compounds and are among the most promising anticancer agents. Here, we demonstrate that the flavonoid astragalin (AG), also known as kaempferol-3-O-β-D-glucoside, induces cell death. This was prevented by the caspase inhibitors z-DEVD-FMK and z-LEHD-FMK. AG-induced cell death was associated with an increase in the Bax:Bcl-2 ratio and amplified by the inhibition of extracellular signal-regulated kinase (ERK)-1/2 and Akt signaling. Meanwhile, AG suppressed LPS-induced NF-κB activation. Additional studies revealed that AG inhibited tumor necrosis factor-alpha (TNFα)-induced NF-κB activity. AG also potentiated TNFα-induced apoptosis in A549 cells. Furthermore, using a mouse xenograft model, we demonstrated that AG suppressed tumor growth and induced cancer cell apoptosis in vivo. Taken together, these results suggest that AG may be a promising cancer therapeutic drug that warrants further investigation into its potential clinical applications.

NFkB hyperactivation causes invasion of esophageal squamous cell carcinoma with EGFR overexpression and p120-catenin down-regulation

Four out of five patients diagnosed with esophageal squamous cell carcinoma (ESCC) will die within five years. This is primarily a result of the aggressive invasive potential of the disease. Our research is focused on the interplay between tumor suppressors and oncogenes in the invasive process. Specifically, EGFR and p120-catenin (p120ctn) are commonly dysregulated genes that are indicative of poor prognosis in ESCC. In a previous study we demonstrated that in our 3D organotypic culture model, only when EGFR overexpression is combined with p120ctn inactivation do the cells transform and invade – as opposed to either event alone. The purpose of this present study was to identify the components of the molecular pathways downstream of p120ctn and EGFR that lead to invasion. Using both human esophageal keratinocytes and human ESCC cells, we have identified NFkB as a central regulator of the invasive process downstream of p120ctn down-regulation and EGFR overexpression. Interestingly, we found that NFkB is hyperactivated in cells with EGFR overexpression and p120ctn inactivation than with either EGFR or p120ctn alone. Inhibition of this NFkB hyperactivation results in complete loss of invasion, suggesting that NFkB signaling is necessary for invasion in this aggressive cell type. Furthermore, we have identified RhoA and Rho-kinase as upstream regulators of NFkB in this process. We believe the cooperation of p120ctn down-regulation and EGFR overexpression is not only important in the aggressive mechanisms of ESCC but could be broadly applicable to many other cancer types in which p120ctn and EGFR are involved.

Gleditsia Saponin C Induces A549 Cell Apoptosis via Caspase-Dependent Cascade and Suppresses Tumor Growth on Xenografts Tumor Animal Model

Saponins are natural compounds and possess the most promising anti-cancer function. Here, a saponin gleditsia saponin C (GSC), extracted from gleditsiae fructus abnormalis, could induce apoptosis of lung tumor cell line A549 via caspase dependent cascade and this effect could be prevented by the caspase inhibitors. In addition, GSC induced cell death companied with an increase ratio of Bax:Bcl-2 and inhibition of ERK and Akt signaling pathways. Meanwhile, GSC suppressed TNFα inducing NF-κB activation and increased the susceptibility of lung cancer cell to TNFα induced apoptosis. Furthermore, on mouse xenograft model, GSC significantly suppressed tumor growth and induced cancer cell apoptosis, which validated the anti-tumor effect of GSC. Based on these results, GSC might be a promising drug candidate of anti-lung cancer for its potential clinical applications.

Microenvironmental regulation of the progression of oral potentially malignant disorders towards malignancy

Oral potentially malignant disorders (OPMD) develop in a complex tissue microenvironment where they grow sustainably, acquiring oral squamous cell carcinoma (OSCC) characteristics. The malignant tumor depends on interactions with the surrounding microenvironment to achieve loco-regional invasion and distant metastases. Unlike abnormal cells, the multiple cell types in the tissue microenvironment are relatively stable at the genomic level and, thus, become therapeutic targets with lower risk of resistance, decreasing the risk of OPMD acquiring cancer characteristics and carcinoma recurrence. However, deciding how to disrupt the OPMD and OSCC microenvironments is itself a daunting challenge, since their microenvironments present opposite capacities, resulting in diverse consequences. Furthermore, recent studies revealed that tumor-associated immune cells also participate in the process of differentiation from OPMD to OSCC, suggesting that reeducating stromal cells may be a new strategy to prevent OPMD from acquiring OSCC characteristics and to treat OSCC. In this review, we discuss the characteristics of the microenvironment of OPMD and OSCC as well as new therapeutic strategies.

Collagen gel protects L929 cells from TNFα-induced death by activating NF-κB

PURPOSE

Type I collagen is one of the most abundant components of extracellular matrix. We previously illustrated that murine fibrosarcoma L929 cells grew well on type I collagen gel and escaped from TNFα-induced cell death. In this study, we investigated the mechanism underlying the protective effect of collagen gel.

MATERIAL AND METHODS

We used western blot, confocal microscopy, MTT assay and flow cytometry by introducing fluorescence staining to determine the expression levels of nuclear factor kappa B (NF-κB), inhibitory ratio and autophagy.

RESULTS

L929 cells on collagen gel showed higher expression of NF-κB in the nucleus. Inhibition of NF-κB with pyrrolidine dithiocarbamate hydrochloride (PDTC) or knockdown by NF-κB-siRNA canceled the protective effect of collagen gel on L929 cells from TNFα-induced death, suggesting for the role of NF-κB in the protection from cell death. We found a new aspect of the effect of PDTC on L929 cells cultured on collagen gel. PDTC alone without TNFα induced apoptosis in the L929 cells cultured on collagen gel but not the cells on plastic dish. The apoptosis induction of the L929 cells cultured on collagen gel with PDTC was repressed by inhibiting autophagy with chloroquine, an autophagy inhibitor, suggesting that autophagy contributes to the death induced by the treatment with PDTC. Possible underlying mechanism of this finding is discussed.

CONCLUSION

NF-κB played an important role in protecting the L929 cells cultured on collagen gel from TNFα-induced death.

cIAP2 promotes gallbladder cancer invasion and lymphangiogenesis by activating the NF-κB pathway

Several studies have produced contradictory findings about the prognostic implications for inhibitor of apoptosis proteins (IAP) in different types of cancer. Cellular inhibitor of apoptosis 2 (cIAP2/BIRC) is one of the most extensively characterized human IAP. To date, no studies have focused on the expression level of cIAP2 in human gallbladder cancer (GBC), and the mechanism of cIAP2 in GBC invasion and lymphangiogenesis remains unclear. Therefore, in the present study, cIAP2 expression in GBC was detected using quantitative real‐time polymerase chain reaction and immunohistochemistry, and the relationship between cIAP2 levels in cancer tissues and the clinicopathological characteristics of patients was analyzed. The biological effect of cIAP2 in GBC cells was tested using the Cell Counting Kit‐8 Assay, Transwell assays and the ability of human dermal lymphatic endothelial cells (HDLEC) to undergo tube formation. The role of cIAP2 in activating the NF‐κB pathway was determined using a dual‐luciferase reporter assay, immunofluorescence staining, western blotting and ELISA. Finally, an animal model was used to further confirm the role of cIAP2 in lymphangiogenesis. We showed that cIAP2 expression was elevated in human GBC tissues and correlated with a negative prognosis for patients. Moreover, cIAP2 was identified as a lymphangiogenic factor of GBC cells and, thus, promoted lymph node metastasis in GBC cells. Our study is the first to suggest that cIAP2 can promote GBC invasion and lymphangiogenesis by activating the NF‐κB pathway.

Thymoquinone inhibits the migration of mouse neuroblastoma (Neuro-2a) cells by down-regulating MMP-2 and MMP-9

Thymoquinone (TQ), an active component derived from the medial plant Nigella sativa, has been used for medical purposes for more than 2 000 years. Recent studies have reported that TQ blocked angiogenesis in animal model and reduced migration, adhesion, and invasion of glioblastoma cells. We have recently shown that TQ could exhibit a potent cytotoxic effect and induce apoptosis in mouse neuroblastoma (Neuro-2a) cells. In the present study, TQ treatment markedly decreased the adhesion and migration of Neuro-2a cells. TQ down-regulated MMP-2 and MMP-9 protein expression and mRNA levels and their activities. Furthermore, TQ significantly down-regulated the protein expression of transcription factor NF-κB (p65) but not significantly altered the expression of N-Myc. Taken together, our data indicated that TQ's inhibitory effect on the migration of Neuro-2a cells was mediated through the suppression of MMP-2 and MMP-9 expression, suggesting that TQ treatment can be a promising therapeutic strategy for human malignant neuroblastoma.

Fine-mapping of antipsychotic response genome-wide association studies reveals novel regulatory mechanisms

Aim: Noncoding variation has demonstrated regulatory effects on disease treatment outcomes. This study investigated the potential functionality of previously implicated noncoding variants on schizophrenia treatment response. Materials & methods: Predicted regulatory potential of variation identified from antipsychotic response genome-wide association studies was determined. Prioritized variants were assessed for association(s) with treatment outcomes in a South African first episode schizophrenia cohort (n = 103). Results: Bioinformatic and association results implicated a relationship between regulatory variants, expression of MANBA, COL9A2 and NFKB1, and treatment response. Three SNPs were associated with poor outcomes (rs230493: p = 1.88 × 10-6; rs3774959: p = 1.75 × 10-5; and rs230504: p = 1.48 × 10-4). Conclusion: This study has thoroughly investigated previous GWAS to pinpoint variants that may play a causal role in poor schizophrenia treatment outcomes, and provides potential candidate genes for further study in the field of antipsychotic response.

Nanomedicine based curcumin and doxorubicin combination treatment of glioblastoma with scFv-targeted micelles: In vitro evaluation on 2D and 3D tumor models

NF-κB is strongly associated with poor prognosis of different cancer types and an important factor responsible for the malignant phenotype of glioblastoma. Overcoming chemotherapy-induced resistance caused by activation of PI3K/Akt and NF-κB pathways is crucial for successful glioblastoma therapy. We developed an all-in-one nanomedicine formulation for co-delivery of a chemotherapeutic agent (topoisomerase II inhibitor, doxorubicin) and a multidrug resistance modulator (NF-κB inhibitor, curcumin) for treatment of glioblastoma due to their synergism. Both agents were incorporated into PEG-PE-based polymeric micelles. The glucose transporter-1 (GLUT1) is overexpressed in many tumors including glioblastoma. The micellar system was decorated with GLUT1 antibody single chain fragment variable (scFv) as the ligand to promote blood brain barrier transport and glioblastoma targeting. The combination treatment was synergistic (combination index, CI of 0.73) against U87MG glioblastoma cells. This synergism was improved by micellar encapsulation (CI: 0.63) and further so with GLUT1 targeting (CI: 0.46). Compared to non-targeted micelles, GLUT1 scFv surface modification increased the association of micelles (>20%, P<0.01) and the nuclear localization of doxorubicin (∼3-fold) in U87MGcells, which also translated into enhanced cytotoxicity. The increased caspase 3/7 activation by targeted micelles indicates successful apoptosis enhancement by combinatory treatment. Moreover, GLUT1 targeted micelles resulted in deeper penetration into the 3D spheroid model. The increased efficacy of combination nanoformulations on the spheroids compared to a single agent loaded, or to non-targeted formulations, reinforces the rationale for selection of this combination and successful utilization of GLUT1 scFv as a targeting agent for glioblastoma treatment.

Thymoquinone chemosensitizes colon cancer cells through inhibition of NF-κB

In the present study, the effects and molecular mechanisms of thymoquinone (TQ) on colon cancer cells were investigated. Cell viability was determined using a Cell Counting Kit-8 assay, and the results revealed that treatment with TQ significantly decreased cell viability in COLO205 and HCT116 cells in a dose-dependent manner. TQ treatment additionally sensitized COLO205 and HCT116 cells to cisplatin therapy in a concentration-dependent manner. To investigate the molecular mechanisms of TQ action, western blot analysis was used to determine the levels of phosphorylated p65 and nuclear factor-κB (NF-κB)-regulated gene products vascular endothelial growth factor (VEGF), c-Myc and B-cell lymphoma 2 (Bcl-2). The results indicated that TQ treatment significantly decreased the level of phosphorylated p65 in the nucleus, which indicated the inhibition of NF-κB activation by TQ treatment. Treatment with TQ also decreased the expression levels of VEGF, c-Myc and Bcl-2. In addition, the inhibition of NF-κB activation with a specific inhibitor, pyrrolidine dithiocarbamate, potentiated the induction of cell death and caused a chemosensitization effect of TQ in colon cancer cells. Overall, the results of the present study suggested that TQ induced cell death and chemosensitized colon cancer cells by inhibiting NF-κB signaling.

2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside suppresses human colorectal cancer cell metastasis through inhibiting NF-κB activation

2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (THSG), a major component of Polygonum multiflorum Thunb (He-Shou-Wu), has been reported to exhibit antioxidant and anti-inflammatory effects. However, its anti-metastatic effect against colorectal cancer is still unclear. In this study, cell migration, invasion and adhesion abilities as well as metastasis-associated protein and NF-κB pathway signaling factor expression were analyzed after treating HT-29 cells with THSG. According to the results, the migration and invasiveness of HT-29 cells were reduced after treatment with 5 or 10 mM THSG (p<0.05). Additionally, the levels of matrix metalloproteinase-2 (MMP-2) and phosphorylated VE-cadherin in HT-29 cells were reduced and the transepithelial electrical resistance (TEER) of EA.hy926 endothelial cell monolayers was increased after incubation in THSG for 24 h (p<0.05). Cell adhesion ability and the E-selectin and intercellular adhesion molecule-1 (ICAM-1) protein levels were reduced when EA.hy926 endothelial cells were treated with THSG (p<0.05). In addition, the cytoplasmic phosphorylation of IκB, the nuclear p65 level and the DNA-binding activity of NF-κB were reduced after treating HT-29 or EA.hy926 cells with 5 or 10 mM THSG (p<0.05). These results suggest that THSG inhibits HT-29 cell metastasis by suppressing cell migration, invasion and adhesion. Furthermore, THSG inhibits metastasis-associated protein expression by suppressing NF-κB pathway activation.

The detective, prognostic, and predictive value of DNA methylation in human esophageal squamous cell carcinoma

Esophageal cancer is one of the most common malignancies in the world. Squamous cell carcinoma accounts for approximately 90 % of esophageal cancer cases. Genetic and epigenetic changes have been found to accumulate during the development of various cancers, including esophageal squamous carcinoma (ESCC). Tobacco smoking and alcohol consumption are two major risk factors for ESCC, and both tobacco and alcohol were found to induce methylation changes in ESCC. Growing evidence demonstrates that aberrant epigenetic changes play important roles in the multiple-step processes of carcinogenesis and tumor progression. DNA methylation may occur in the key components of cancer-related signaling pathways. Aberrant DNA methylation affects genes involved in cell cycle, DNA damage repair, Wnt, TGF-β, and NF-κB signaling pathways, including P16, MGMT, SFRP2, DACH1, and ZNF382. Certain genes methylated in precursor lesions of the esophagus demonstrate that DNA methylation may serve as esophageal cancer early detection marker, such as methylation of HIN1, TFPI-2, DACH1, and SOX17. CHFR methylation is a late stage event in ESCC and is a sensitive marker for taxanes in human ESCC. FHIT methylation is associated with poor prognosis in ESCC. Aberrant DNA methylation changes may serve as diagnostic, prognostic, and chemo-sensitive markers. Characterization of the DNA methylome in ESCC will help to better understand its mechanisms and develop improved therapies.

AGK enhances angiogenesis and inhibits apoptosis via activation of the NF-κB signaling pathway in hepatocellular carcinoma

High levels of angiogenesis and resistance to apoptosis are major clinical features of hepatocellular carcinoma (HCC), a lethal disease with a high incidence worldwide. However, the precise mechanisms underlying these malignant properties remain unclear. Here, we demonstrated that acylglycerol kinase (AGK) is markedly overexpressed in HCC cell lines and clinical tissues. Immunohistochemical analysis of 245 clinical HCC specimens revealed patients with high levels of AGK expression had poorer overall survival compared to patients with low AGK expression. Furthermore, overexpressing AGK significantly enhanced angiogenesis and inhibited apoptosis in vitro and promoted the tumorigenicity of HCC cells in vivo; silencing endogenous AGK had the opposite effects. Importantly, AGK enhanced angiogenesis and inhibited apoptosis in HCC in part via activation of NF-κB signaling. Our findings provide new evidence that AGK plays an important role in promoting angiogenesis and providing resistance to apoptosis, thus AGK may represent a novel therapeutic target for HCC.

A sphingosine kinase-1 inhibitor, SKI-II, induces growth inhibition and apoptosis in human gastric cancer cells

SKI-II has been reported as an inhibitor of sphingosine kinase 1 and has been extensively used to prove the involvement of sphingosine kinase and sphingosine-1-phosphate (Sphk1) in cellular processes. In the current study, we investigated the effects of SKI-II and its potential mechanisms in human gastric cancer SGC7901 cells. After treatment with SKI-II, cell growth, cell cycle distribution, apoptosis, expression of Sphk1, NF-κB, Bcl-2, Bax and p27 were assessed by MTT assay, flow cytometry, electron microscopy, immunocytochemistry and Western-blot assay, respectively. Our results showed that SKI-II markedly inhibited SGC7901 cell survival in a dose-dependent manner, reduced cell proliferation with accumulation of cells in the G0/G1 phase and induced apoptosis in the tumor cells. Furthermore, Western blotting and immunocytochemistry showed that the expression of p27 and Bax was increased significantly, but the expression of NF-κB, Bcl-2 and Sphk1 decreased by different degrees. These results indicate that SKI-II induced cell growth arrest and apoptosis. The increased apoptotic sensitivity of SGC7901 was correlated with NF-κB or Bcl-2/Bax activation.

Proinflammatory cytokine levels in oral lichen planus, oral leukoplakia, and oral submucous fibrosis

OBJECTIVES

The objective of this study was to identify salivary and serum concentrations of interleukin (IL)-8, IL-6, and tumor necrosis factor alpha (TNF-α) in patients with oral lichen planus, oral leukoplakia, oral submucous fibrosis, and healthy controls.

MATERIALS AND METHODS

Patients selected included 54 oral lichen planus (41 to 65 years), 50 oral leukoplakia (42 to 65 years), 51 oral submucous fibrosis (41 to 65 years), and 50 healthy controls (42 to 65 years). Oral lichen planus, oral leukoplakia, and oral submucous fibrosis cases were diagnosed using histopathological analysis. Salivary and serum cytokine concentrations were measured using enzyme-linked immunoassay kits in all subjects.

RESULTS

The levels of serum and salivary TNF-α, IL-6, and IL-8 were statistically significantly increased in oral leukoplakia, submucous fibrosis, and lichen planus in contrast to normal healthy subjects (P<0.05). Serum and salivary correlation analysis revealed strong and highly significant correlations for TNF-α, IL-6, and IL-8 in all groups (r=0.72-0.82, P<0.05).

CONCLUSION

Salivary and serum cytokines were also elevated when analyzed in oral precancerous lesions. Thus, salivary and serum IL-8, IL-6, and TNF-α levels might act as diagnostic markers for detection of oral precancer.

Soy and breast cancer: focus on angiogenesis

Epidemiological studies have revealed that high consumption of soy products is associated with low incidences of hormone-dependent cancers, including breast and prostate cancer. Soybeans contain large amounts of isoflavones, such as the genistein and daidzain. Previously, it has been demonstrated that genistein, one of the predominant soy isoflavones, can inhibit several steps involved in carcinogenesis. It is suggested that genistein possesses pleiotropic molecular mechanisms of action including inhibition of tyrosine kinases, DNA topoisomerase II, 5α-reductase, galectin-induced G2/M arrest, protein histidine kinase, and cyclin-dependent kinases, modulation of different signaling pathways associated with the growth of cancer cells (e.g., NF-κB, Akt, MAPK), etc. Moreover, genistein is also a potent inhibitor of angiogenesis. Uncontrolled angiogenesis is considered as a key step in cancer growth, invasion, and metastasis. Genistein was found to inhibit angiogenesis through regulation of multiple pathways, such as regulation of VEGF, MMPs, EGFR expressions and NF-κB, PI3-K/Akt, ERK1/2 signaling pathways, thereby causing strong antiangiogenic effects. This review focuses on the antiangiogenic properties of soy isoflavonoids and examines their possible underlying mechanisms.

Involvement of the nuclear factor-κB signaling pathway in the regulation of CXC chemokine receptor-4 expression in neuroblastoma cells induced by tumor necrosis factor-α

Metastasis is a hallmark of malignant neuroblastoma and is the main reason for therapeutic failure and recurrence of the tumor. The CXC chemokine receptor-4 (CXCR4), a Gi protein-coupled receptor for the ligand CXCL12/stromal cell-derived factor-1α (SDF-1α), is expressed in various types of tumor. This receptor mediates the homing of tumor cells to specific organs that express the ligand, CXCL12, for this receptor and plays an important role in tumor growth, invasion, metastasis and angiogenesis. In the present study, the inflammatory cytokine, tumor necrosis factor‑α (TNF‑α) upregulated CXCR4 expression in neuroblastoma cells and increased migration to the CXCR4 ligand SDF‑1α. In addition, this effect was dependent upon NF-κB transcriptional activity, as blocking the NF-κB pathway with pyrrolidinedithiocarbamic acid ammonium salt suppressed TNF-α‑induced upregulation of CXCR4 expression and reduced the migration towards the CXCR4 ligand, SDF-1α. Treating neuroblastoma cells with TNF-α resulted in the activation of nuclear factor-kappa B (NF-κB) and subsequently, the translocation of NF-κB from the cytoplasm to the nucleus. Using immunohistochemistry, NF‑κB and CXCR4 were significantly correlated with each other (P=0.0052, Fisher's exact test) in a cohort of neuroblastoma samples (n=80). The present study indicates that the inflammatory cytokine, TNF-α, partially functions through the NF‑κB signaling pathway to upregulate CXCR4 expression to foster neuroblastoma cell metastasis. These findings indicate that effective inhibition of neuroblastoma metastasis should be directed against the inflammatory cytokine-induced NF‑κB/CXCR4/SDF‑1α signaling pathway.

TNF-α receptor 1 expression predicts poor prognosis of diffuse large B-cell lymphoma, not otherwise specified

We have previously shown that in tumor specimens from patients with diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS), the tumor necrosis factor-α (TNF-α)-positive type correlates with a poorer prognosis compared with the TNF-α-negative type. In the present study, we further evaluated 60 lymphoma tissue specimens from patients with DLBCL, NOS by immunohistochemical staining with antibodies against TNF-α receptor 1 (TNFR1) and TNF-α receptor 2 (TNFR2). Our results demonstrated that 31 cases (52%) were positive and 29 (48%) were negative for TNFR1 and that the TNFR1-positive cases were significantly correlated with a poorer overall survival (OS; P=0.0006, log rank test) than the TNFR1-negative cases. The TNFR2-positive cases tended to have a poorer OS than the TNFR2-negative cases, although the difference was not significant. TNFR1 expression in tumor cells was a significant prognostic factor for OS and was independent of the International Prognostic Index (IPI). Among 31 TNF-α-positive DLBCL, NOS cases, 27 (87%) were positive and 4 (13%) were negative for TNFR1. Both TNF-α-positive and TNFR1-positive cases were significantly correlated with a poorer OS compared with the TNF-α-positive but TNFR1-negative cases. Twenty-seven cases (45%) with the TNF-α-positive and TNFR1-positive subtype of DLBCL, NOS had a poorer prognosis for OS and progression-free survival compared with the 33 cases (55%) with the remaining subtypes, and the TNF-α-positive and TNFR1-positive subtype of DLBCL, NOS was also shown to be independent of the IPI. In addition to the IPI, the prognosis of patients can be more accurately identified by evaluating both TNF-α and TNFR1 expression.

Crebanine, an aporphine alkaloid, sensitizes TNF-α-induced apoptosis and suppressed invasion of human lung adenocarcinoma cells A549 by blocking NF-κB-regulated gene products

Crebanine is an alkaloid known to exhibit anticancer, but its mechanism is not well understood. Besides, the nuclear factor-kappa B (NF-κB) transcription factor has been correlated with inflammation, carcinogenesis, tumor cell survival, invasion, and angiogenesis. In this study, we investigated the effects of crebanine on tumor necrosis factor alpha (TNF-α)-induced NF-κB activation and the expression of NF-κB-regulated gene products. We found that crebanine reduced the cell proliferation of lung, ovarian, and breast cancer cells. Crebanine also potentiated TNF-α-induced apoptosis which correlated with the suppression of the gene products linked to cell survival, B cell lymphoma-extra large, and proliferation, cyclin D1. In addition, crebanine affected TNF-α-induced activation of caspase-8, caspase-3, and poly(ADP-ribose) polymerase cleavage, indicating that the apoptotic effects of TNF-α were enhanced by crebanine. Moreover, crebanine reduced TNF-α-induced A549 cell invasion and migration. Furthermore, crebanine suppressed the TNF-α-mediated expression of proteins that involved cancer cell invasion (matrix metalloproteinase 9 urokinase-type plasminogen activator, urokinase-type plasminogen activator receptor and intercellular adhesion molecule 1) and angiogenesis (COX-2 and VEGF), all of which are known to be regulated by NF-κB. We also demonstrated that TNF-α induced NF-κB DNA-binding activity, which was inhibited by crebanine. Moreover, crebanine suppressed the TNF-α-induced degradation of inhibitor of NF-κB alpha (IκBa), which led to reduced NF-κB translocation to the nucleus. Taken together, our results demonstrated that crebanine reduced TNF-α-induced cancer cell proliferation, invasion, and survival by suppressing NF-κB activity and expression profile of its downstream genes.

TNF-α expression in tumor cells as a novel prognostic marker for diffuse large B-cell lymphoma, not otherwise specified

Several cytokines promote malignant cell growth and are therefore believed to contribute to disease aggressiveness. The cytokine tumor necrosis factor-α (TNF-α) acts as a tumor-promoting factor and has been linked to all tumorigenic stages in many cancers. Here, we evaluated 62 lymphoma tissue specimens from patients having diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS) by immunostaining with anti-TNF-α antibody. Cytoplasmic TNF-α reactivity in ≥20% of the tumor cells was considered positive. Our results demonstrated that tumor specimens from DLBCL, NOS patients could be divided into 2 types-TNF-α positive (38 cases, 61%) and TNF-α negative (24 cases, 39%)--and that TNF-α positivity in DLBCL, NOS was correlated with poorer overall survival (OS; P=0.0005, log rank test) and progression-free survival (PFS; P=0.0330, log rank test) compared with TNF-α negativity. Cox regression analysis showed that TNF-α expression was a significant prognostic factor for OS (P<0.0001) and PFS (P=0.0323). Regarding OS and PFS, multivariate analysis showed that TNF-α expression in tumor cells was an independent prognostic factor for the International Prognostic Index (IPI). Therefore, TNF-α-positive DLBCL, NOS may constitute a unique subtype of DLBCL, NOS with an aggressive clinical course. The addition of TNF-α expression to the IPI may significantly improve the predictive prognostic value. The therapeutic strategy of DLBCL, NOS patients should be based on correct prognosis; therefore, patients with poor prognoses could be more accurately detected by evaluating both TNF-α expression levels and the IPI.

[6]-Gingerol Prevents Disassembly of Cell Junctions and Activities of MMPs in Invasive Human Pancreas Cancer Cells through ERK/NF- κ B/Snail Signal Transduction Pathway

To study the effects of [6]-gingerol, a ginger phytochemical, on tight junction (TJ) molecules, we investigated TJ tightening and signal transduction pathways in human pancreatic duct cell-derived cancer cell line PANC-1. The following methods were utilized: MTT assay to determine cytotoxicity; zymography to examine matrix metalloproteinase (MMP) activities; transepithelial electrical resistance (TER) and paracellular flux for TJ measurement; RT-PCR and immunoblotting for proteins related to TJ and invasion; and EMSA for NF- κ B activity in PANC-1 cells. Results revealed that TER significantly increased and claudin 4 and MMP-9 decreased compared to those of the control. TJ protein levels, including zonula occludens (ZO-) 1, occludin, and E-cadherin, increased in [6]-gingerol-treated cells, which correlated with a decrease in paracellular flux and MMP activity. Furthermore, NF- κ B/Snail nuclear translocation was suppressed via downregulation of the extracellular signal-regulated kinase (ERK) pathway in response to [6]-gingerol treatment. Moreover, treatment with U0126, an ERK inhibitor, completely blocked NF- κ B activity. In conclusion, these findings demonstrate that [6]-gingerol regulates TJ-related proteins and suppresses invasion and metastasis through NF- κ B/Snail inhibition via inhibition of the ERK pathway. Therefore, [6]-gingerol may suppress the invasive activity of PANC-1 cells.

Tumor suppressor ING4 overexpression contributes to proliferation and invasion inhibition in gastric carcinoma by suppressing the NF-κB signaling pathway

There is growing evidence that inhibitor of growth 4 (ING4) plays a pivotal role in development and progression of multiple different tumors; however, its precise function in gastric carcinoma remains to be elucidated. In the present study, we investigated ING4 level in gastric carcinoma tissues and cells, and preliminarily elucidated the role of ING4 in the proliferation and invasion of gastric carcinoma. The results demonstrated that expressions of ING4 mRNA and protein in gastric carcinoma tissues and cells were significantly lower than those in normal tissues and cells (P < 0.05). ING4 level in gastric carcinoma cells stably expressing ING4 was markedly higher than those in untreated group and empty vector pcDNA3.1 group (P < 0.05). Elevated ING4 level resulted in the inhibition of proliferation and invasion in three of gastric carcinoma cell lines MKN-28, SGC-7901 and MKN-45. Most notably, increased ING4 level evidently evoked the down-regulation of p65, p-IκBα, MMP-9 and uPA proteins and the up-regulation of IκBα protein. Our results presented herein suggest that ING4 level elevation mediated proliferation and invasion inhibition may be tightly associated with the suppression of NF-κB signaling pathway.

IAPs on the move: role of inhibitors of apoptosis proteins in cell migration

Inhibitors of Apoptosis Proteins (IAPs) are a class of highly conserved proteins predominantly known for the regulation of caspases and immune signaling. However, recent evidence suggests a crucial role for these molecules in the regulation of tumor cell shape and migration by controlling MAPK, NF-κB and Rho GTPases. IAPs directly control Rho GTPases, thus regulating cell shape and migration. For instance, XIAP and cIAP1 function as the direct E3 ubiquitin ligases of Rac1 and target it for proteasomal degradation. IAPs are differentially expressed in tumor cells and have been targeted by several cancer therapeutic drugs that are currently in clinical trials. Here, we summarize the current knowledge on the role of IAPs in the regulation of cell migration and discuss the possible implications of these observations in regulating tumor cell metastases.

Liposome-encapsulated curcumin suppresses neuroblastoma growth through nuclear factor-kappa B inhibition

BACKGROUND

Nuclear factor-κB (NF-κB) has been implicated in tumor cell proliferation and survival and in tumor angiogenesis. We sought to evaluate the effects of curcumin, an inhibitor of NF-κB, on a xenograft model of disseminated neuroblastoma.

METHODS

For in vitro studies, neuroblastoma cell lines NB1691, CHLA-20, and SK-N-AS were treated with various doses of liposomal curcumin. Disseminated neuroblastoma was established in vivo by tail vein injection of NB1691-luc cells into SCID mice, which were then treated with 50 mg/kg/day of liposomal curcumin 5 days/week intraperitoneally.

RESULTS

Curcumin suppressed NF-κB activation and proliferation of all neuroblastoma cell lines in vitro. In vivo, curcumin treatment resulted in a significant decrease in disseminated tumor burden. Curcumin-treated tumors had decreased NF-κB activity and an associated significant decrease in tumor cell proliferation and an increase in tumor cell apoptosis, as well as a decrease in tumor vascular endothelial growth factor levels and microvessel density.

CONCLUSION

Liposomal curcumin suppressed neuroblastoma growth, with treated tumors showing a decrease in NF-κB activity. Our results suggest that liposomal curcumin may be a viable option for the treatment of neuroblastoma that works via inhibiting the NF-κB pathway.

TNIP1, a retinoic acid receptor corepressor and A20-binding inhibitor of NF-κB, distributes to both nuclear and cytoplasmic locations

An increasingly wide range of functions, from repression of NF-κB signaling to protection from apoptosis, is being recognized for tumor necrosis factor α-induced protein 3-interacting protein 1 (TNIP1). The authors recently demonstrated TNIP1 interaction with and repression of liganded retinoic acid receptors, distinguishing it from the more typical NCoR and SMRT corepressors, which function only in the absence of ligand. To improve their understanding of TNIP1's roles in physiologic and pathologic events, the authors examined its distribution in normal and malignant human tissues and cultured cells. They found cytoplasmic and nuclear TNIP1 in normal skin keratinocytes as it colocalized with retinoic acid receptor α, one of the nuclear receptors it corepresses. Nuclear and cytoplasmic TNIP1 was also found in the malignant keratinocytes of squamous cell carcinomas. Compared to adjacent normal tissues of other organs, TNIP1 staining and distribution varied with increased levels in esophageal cancer and marked decreases in prostate cancer. The varying levels and distribution of TNIP1 in normal and disease state tissues could be expected to affect processes in which TNIP1 is involved, such as NF-κB and nuclear receptor signaling, possibly contributing to the disease course or response to therapies targeting these key players of cell growth and differentiation.

Different patterns of NF-κB and Notch1 signaling contribute to tumor-induced lymphangiogenesis of esophageal squamous cell carcinoma

Background

Lymph node involvement and tumor-induced lymphangiogenesis appear as the earliest features of esophageal squamous cell carcinoma (ESCC), although the molecular regulatory mechanisms involved have remained unclear. Our aim was to investigate the contribution of NF-κB and Notch1 signaling to lymph node involvement and tumor-induced lymphangiogenesis in ESCC.

Material and methods

NF-κB and Notch1 expression in 60 tissue samples of ESCC were assessed by immunohistochemical staining. The correlations of NF-κB and Notch1 with lymph node involvement, lymphatic vessel density (LVD), podoplanin, and vascular endothelial growth factor-C (VEGF-C) were further evaluated to determine the association of NF-κB and Notch1 expression with tumor-induced lymphangiogenesis.

Results

Chi-square tests revealed that NF-κB and Notch1 expression in ESCC tissues were significant associated with lymph node metastasis, LVD, podoplanin, and VEGF-C expression. Strong expression of NF-κB, but weak expression of Notch1, was observed in tumor tissues with lymph nodes involvement (P < 0.05 for both). The mean histoscores of LVD, podoplanin, and VEGF-C staining were higher in high-NF-κB-expressing tissue than in low-expressing tissue (P < 0.05 for each). In contrast, the mean histoscores of LVD and VEGF-C staining were lower in high-Notch1-expressing tissue than in low-expressing tissue (P < 0.05 for both). A multiple factors analysis of LVD and VEGF-C further demonstrated that LVD and VEGF-C status were significantly correlated with NF-κB and Notch1 expression in tumors. NF-κB and Notch1 expression were also significantly inversely correlated (P < 0.05).

Conclusion

These results suggest that different patterns of NF-κB and Notch1 signaling contribute to lymph nodes metastasis and tumor-induced lymphangiogenesis of ESCC, and reveal that up-regulation of NF-κB is associated with down-regulation of Notch1 in tumor tissue.

Caffeic acid phenethyl ester inhibits invasion and expression of matrix metalloproteinase in SK-Hep1 human hepatocellular carcinoma cells by targeting nuclear factor kappa B

Numerous studies have shown that the levels of matrix metalloproteinase (MMP)-2 and/or MMP-9 are associated with the invasive phenotypes of cancer cells. This study investigated the effects of caffeic acid phenethyl ester (CAPE), a chemopreventive phytochemical derived from honeybee propolis, on the invasive phenotype of SK-Hep1 human hepatocellular carcinoma cells (SK-Hep1 cells). CAPE effectively suppressed SK-Hep1 cell invasion in a dose-dependent manner. The constitutive expression of MMP-2 and MMP-9 in SK-Hep1 cells was almost completely abolished by treatment with 12.5 muM CAPE. CAPE also significantly inhibited nuclear factor kappa B (NF-kappaB) DNA-binding activity in SK-Hep1 cells. These results taken together suggest that CAPE exerts antimetastatic potential through inhibition of MMP-2 and MMP-9 expression, possibly by targeting NF-kappaB in hepatocellular carcinoma.

Similar NF-κB gene signatures in TNF-α treated human endothelial cells and breast tumor biopsies

BACKGROUND

Endothelial dysfunction has been implicated in the pathogenesis of diverse pathologies ranging from vascular and immune diseases to cancer. TNF-α is one of the mediators of endothelial dysfunction through the activation of transcription factors, including NF-κB. While HUVEC (macrovascular cells) have been largely used in the past, here, we documented an NF-κB gene signature in TNFα-stimulated microvascular endothelial cells HMEC often used in tumor angiogenesis studies.

METHODOLOGY/PRINCIPAL FINDINGS

We measured mRNA expression of 55 NF-κB related genes using quantitative RT-PCR in HUVEC and HMEC. Our study identified twenty genes markedly up-regulated in response to TNFα, including adhesion molecules, cytokines, chemokines, and apoptosis regulators, some of them being identified as TNF-α-inducible genes for the first time in endothelial cells (two apoptosis regulators, TNFAIP3 and TNFRSF10B/Trail R2 (DR5), the chemokines GM-CSF/CSF2 and MCF/CSF1, and CD40 and TNF-α itself, as well as NF-κB components (RELB, NFKB1 or 50/p105 and NFKB2 or p52/p100). For eight genes, the fold induction was much higher in HMEC, as compared to HUVEC. Most importantly, our study described for the first time a connection between NF-κB activation and the induction of most, if not all, of these genes in HMEC as evaluated by pharmacological inhibition and RelA expression knock-down by RNA interference. Moreover, since TNF-α is highly expressed in tumors, we further applied the NF-κB gene signature documented in TNFα-stimulated endothelial cells to human breast tumors. We found a significant positive correlation between TNF and the majority (85 %) of the identified endothelial TNF-induced genes in a well-defined series of 96 (48 ERα positive and 48 ERα negative) breast tumors.

CONCLUSION/SIGNIFICANCE

Taken together these data suggest the potential use of this NF-κB gene signature in analyzing the role of TNF-α in the endothelial dysfunction, as well as in breast tumors independently of the presence of ERα.

Inhibition of ErbB2 by herceptin reduces viability and survival, induces apoptosis and oxidative stress in Calu-3 cell line

Human epidermal growth factor receptor 2 (ErbB2) amplification and overexpression has been seen in many cancer types including non-small cell lung cancer (NSCLC). Thus, ErbB2 is an important target for cancer therapies. Increased ErbB2 expression has been associated with drug resistance in cancer cells. Herceptin is a humanized monoclonal antibody that targets the extracellular domain of ErbB2. In this study, we aimed to block ErbB2 signaling with Herceptin and assess cytotoxicity and effects on apoptosis, oxidative stress, nuclear factor kappa-B (NF-kB), and Survivin expression in Calu-3 cell line. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay were used to assess cell viability as a marker of proliferation. Acridine orange/ethidium bromide (AO/EB) staining and caspase 3/7 activity were measured as the markers of apoptosis. The relative expressions of NF-kB-p50 and Survivin mRNAs were evaluated. Activities of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), and the levels of glutathione (GSH) and reactive oxygen species (ROS) were determined in a time- and dose-dependent manner. Our results show that Herceptin treatment inhibits cell proliferation and activates apoptosis but without effects on Survivin and NF-kB expression in Calu-3 cell line. Intracellular glutathione levels and SOD and CAT activities were decreased in a time- and dose-dependent manner associated with oxidative stress. Also, ROS were increased at 24 h. These results provide evidence that Herceptin can be used as a cytotoxic and apoptotic agent in NSCLC.

Crotepoxide chemosensitizes tumor cells through inhibition of expression of proliferation, invasion, and angiogenic proteins linked to proinflammatory pathway

Crotepoxide (a substituted cyclohexane diepoxide), isolated from Kaempferia pulchra (peacock ginger), although linked to antitumor and anti-inflammatory activities, the mechanism by which it exhibits these activities, is not yet understood. Because nuclear factor kappaB (NF-kappaB) plays a critical role in these signaling pathways, we investigated the effects of crotepoxide on NF-kappaB-mediated cellular responses in human cancer cells. We found that crotepoxide potentiated tumor necrosis factor (TNF), and chemotherapeutic agents induced apoptosis and inhibited the expression of NF-kappaB-regulated gene products involved in anti-apoptosis (Bcl-2, Bcl-xL, IAP1,(2) MCl-1, survivin, and TRAF1), apoptosis (Bax, Bid), inflammation (COX-2), proliferation (cyclin D1 and c-myc), invasion (ICAM-1 and MMP-9), and angiogenesis (VEGF). We also found that crotepoxide inhibited both inducible and constitutive NF-kappaB activation. Crotepoxide inhibition of NF-kappaB was not inducer-specific; it inhibited NF-kappaB activation induced by TNF, phorbol 12-myristate 13-acetate, lipopolysaccharide, and cigarette smoke. Crotepoxide suppression of NF-kappaB was not cell type-specific because NF-kappaB activation was inhibited in myeloid, leukemia, and epithelial cells. Furthermore, we found that crotepoxide inhibited TAK1 activation, which led to suppression of IkappaBalpha kinase, abrogation of IkappaBalpha phosphorylation and degradation, nuclear translocation of p65, and suppression of NF-kappaB-dependent reporter gene expression. Overall, our results indicate that crotepoxide sensitizes tumor cells to cytokines and chemotherapeutic agents through inhibition of NF-kappaB and NF-kappaB-regulated gene products, and this may provide the molecular basis for crotepoxide ability to suppress inflammation and carcinogenesis.

Correlation of NF-kappaB signal pathway with tumor metastasis of human head and neck squamous cell carcinoma

Background

Nuclear factor-kappa B (NF-κB) signaling constitutes a key event in the multistep process of carcinogenesis, progression and treatment in many cancer types. However, the significance of NF-κB pathway for complex and tissue-specific aspects of head and neck cancer progression, such as invasion and metastasis, is less understood.

Methods

The expression of NF-κB p65 in squamous cell carcinoma of the head and neck (SCCHN) clinical specimens by immunohistochemistry. The role of NF-κB activity in head and neck squamous cell carcinoma was determined by western blot, reporter assay and EMSA analysis in vitro and metastasis assays in vivo in different metastatic potential tumor cells. Furthermore, the apoptosis rate and expression of metastasis-related protein such as MMP9 and VEGF were examined by Annexin V/PI staining and Western blot, respectively.

Results

A higher level of active nuclear-localized NF-κB was observed in the metastatic SCCHN specimens group (p < 0.01). The NF-κB activities of SCCHN cell lines with different metastatic potentials were then determined and in excellent agreement with results found in SCCHN specimens, highly metastatic SCCHN cell lines expressed high level of NF-κB activity. The treatment of highly metastatic SCCHN cells with NF-κB inhibitors reduced the in vitro cell invasion capacity of the cells without affecting the apoptotic rate. Additionally, the NF-κB inhibitors significantly inhibited the experimental lung metastasis of Tb cells and lymph node metastasis of TL cells in nude mice. Furthermore, the expression of metastasis-related proteins, such as matrix metalloproteinase 9 and vascular endothelial growth factor, was inhibited by pyrrolidine dithiocarbonate.

Conclusions

This study suggests that NF-κB activity significantly contributes to tumor hematologic and lymphatic metastases and may aid in the development of early detection methods or therapies targeting non-conventional molecular targets.

Systemic administration of polymeric nanoparticle-encapsulated curcumin (NanoCurc) blocks tumor growth and metastases in preclinical models of pancreatic cancer

Curcumin or diferuloylmethane is a yellow polyphenol extracted from the rhizome of turmeric (Curcuma longa). A large volume (several hundreds) of published reports has established the anticancer and chemopreventative properties of curcumin in preclinical models of every known major cancer type. Nevertheless, the clinical translation of curcumin has been significantly hampered due to its poor systemic bioavailability, which mandates that patients consume up to 8 to 10 g of the free drug orally each day to achieve detectable levels in circulation. We have engineered a polymeric nanoparticle encapsulated curcumin formulation (NanoCurc) that shows remarkably higher systemic bioavailability in plasma and tissues compared with free curcumin upon parenteral administration. In xenograft models of human pancreatic cancer established in athymic mice, administration of parenteral NanoCurc significantly inhibits primary tumor growth in both subcutaneous and orthotopic settings. The combination of parenteral NanoCurc with gemcitabine results in enhanced tumor growth inhibition versus either single agent, suggesting an additive therapeutic influence in vivo. Furthermore, this combination completely abrogates systemic metastases in orthotopic pancreatic cancer xenograft models. Tumor growth inhibition is accompanied by significant reduction in activation of nuclear factor-kappaB, as well as significant reduction in expression of matrix metalloproteinase-9 and cyclin D1, in xenografts treated with NanoCurc and gemcitabine. NanoCurc is a promising new formulation that is able to overcome a major impediment for the clinical translation of curcumin to cancer patients by improving systemic bioavailability, and by extension, therapeutic efficacy.

Inhibiting NF-κB activation by small molecules as a therapeutic strategy

Because nuclear factor-κB (NF-κB) is a ubiquitously expressed proinflammatory transcription factor that regulates the expression of over 500 genes involved in cellular transformation, survival, proliferation, invasion, angiogenesis, metastasis, and inflammation, the NF-κB signaling pathway has become a potential target for pharmacological intervention. A wide variety of agents can activate NF-κB through canonical and noncanonical pathways. Canonical pathway involves various steps including the phosphorylation, ubiquitination, and degradation of the inhibitor of NF-κB (IκBα), which leads to the nuclear translocation of the p50-p65 subunits of NF-κB followed by p65 phosphorylation, acetylation and methylation, DNA binding, and gene transcription. Thus, agents that can inhibit protein kinases, protein phosphatases, proteasomes, ubiquitination, acetylation, methylation, and DNA binding steps have been identified as NF-κB inhibitors. Because of the critical role of NF-κB in cancer and various chronic diseases, numerous inhibitors of NF-κB have been identified. In this review, however, we describe only small molecules that suppress NF-κB activation, and the mechanism by which they block this pathway.