NF-κB in solid tumors

Role of hematological and neurological expressed 1 (HN1) in human cancers

Hematological and neurological expressed 1 (HN1), also known as Jupiter microtubule associated homolog 1 (JPT1), is a highly conserved protein with widespread expression in various tissues. Ectopic elevation of HN1 has been observed in multiple cancers, highlighting its role in tumorigenesis and progression. Both proteomics and transcriptomics reveal that HN1 is closely associated with severe disease progression, poor prognostic and shorter overall survival. HN1's involvement in cancer cell proliferation and metastasis has been extensively investigated. Overexpression of HN1 is associated with increased tumor growth and disease progression, while its depletion leads to cell cycle arrest and apoptosis. The pivotal role of HN1 in cancer progression, particularly in proliferation, migration, and invasion, underscores its significance in cancer metastasis. Validation of the efficacy and safety of HN1 inhibition, along with the development of diagnostic methods to determine HN1 expression levels in patients, is essential for the translation of HN1-targeted therapies into clinical practice. Overall, HN1 emerges as a valuable prognostic marker and therapeutic target in cancer, and further investigations hold the potential to improve patient outcomes by impeding metastasis and enhancing treatment strategies.

A Review on Picrosides Targeting NFκB and its Proteins for Treatment of Breast Cancer

Breast cancer is the most frequently diagnosed disease causing most deaths in women worldwide. Chemotherapy and neo-adjuvant therapy are the standard method of treatment in early stages of breast cancer. However drug resistance in breast cancer limit the use of these methods for treatment. Research focus is now shifted towards identifying natural phytochemicals with lower toxicity. This review illustrates the NF κB interaction with different signaling pathways in normal condition, breast cancer and other cancer and thus represent a potential target for treatment. No reports are available on the action of picrosides on NFκB and its associated proteins for anticancer activity. In the present review, potential interaction of picrosides with NF-κB and its associated proteins is reviewed for anticancer action. Further, an important facet of this review entails the ADMET analysis of Picroside, elucidating key ADMET properties which serves to underscore the crucial characteristics of Picroside as a potential drug for treating breast cancer. Furthermore, in silico analysis of Picrosides was executed in order to get potential binding modes between ligand (Picrosides II) and NFκB.

Role of non-coding RNAs in neuroblastoma

Neuroblastoma is known as the most prevalent extracranial malignancy in childhood with a neural crest origin. It has been widely accepted that non-coding RNAs (ncRNAs) play important roles in many types of cancer, including glioma and gastrointestinal cancers. They may regulate the cancer gene network. According to recent sequencing and profiling studies, ncRNAs genes are deregulated in human cancers via deletion, amplification, abnormal epigenetic, or transcriptional regulation. Disturbances in the expression of ncRNAs may act either as oncogenes or as anti-tumor suppressor genes, and can lead to the induction of cancer hallmarks. ncRNAs can be secreted from tumor cells inside exosomes, where they can be transferred to other cells to affect their function. However, these topics still need more study to clarify their exact roles, so the present review addresses different roles and functions of ncRNAs in neuroblastoma.

Fusion protein and hemagglutinin of canine distemper virus co-induce apoptosis in canine mammary tumor cells

BACKGROUND

Canine distemper virus (CDV) has been shown to have oncolytic activity against primary canine tumors. Previous studies from this laboratory had confirmed that CDV induces apoptosis in canine mammary tumor (CMT) cells, although the molecular mechanism remains unknown.

METHODS

The CDV N, P, M, F, H, L, C, and V genes were identified in CDV-L and cloned separately. Mutants with deletions in the 5' region (pCMV-F L△60, pCMV-FL△107, and pCMV-FL△114) or with site-directed mutagenesis in the 3' region (pCMV-FLA602-610) of the F gene were generated. Late-stage apoptotic cells were detected by Hoechst 33342. Early-stage apoptotic cells were detected by AnnexinV-FITC/PI. Quantitative real-time PCR was performed to detect the mRNA levels of target genes of apoptotic and NF-κB pathway. Western blot analysis was performed to detect the expression or phosphorylation levels of target proteins of apoptotic or NF-κB pathway. Immunofluorescence assay was performed to detect the nuclear translocation of p65 protein. Recombinant viruses (rCDV-FL△60 and rCDV-FLA602-610) were rescued by a BHK-T7-based system. 5-week-old female BALB/c nude mice were used to detect the oncolytic activity of recombinant viruses.

RESULTS

In this study, it was first confirmed that none of the structural or non-structural proteins of CDV-L, a vaccine strain, was individually able to induce apoptosis in canine mammary tubular adenocarcinoma cells (CIPp) or intraductal papillary carcinoma cells (CMT-7364). However, when CIPp or CMT-7364 cells were co-transfected with glycoprotein fusion (F) and hemagglutinin (H) proteins of CDV-L, nuclear fragmentation was observed and a high proportion of early apoptotic cells were detected, as well as cleaved caspase-3, caspase-8 and poly (ATP ribose) polymerase (PARP). Cleaved caspase-3 and PARP were down-regulated by apoptosis broad-spectrum inhibitor Z-VAD-FMK and caspase-8 pathway inhibitor Z-IETD-FMK, confirming that the F and H proteins coinduced apoptosis in CMT cells via the caspase-8 and caspase-3 pathways. F and H proteins co-induced phosphorylation of p65 and IκBα and nuclear translocation of p65, confirming activation of the NF-κB pathway, inhibition of which down-regulated cleaved caspase-3 and cleaved PARP. Recombinant F protein with enhanced fusion activity and H protein co-induced more cleaved caspase-3 and PARP than parental F protein, while the corresponding recombinant virus exhibited the same properties both in CIPp cells and in a subcutaneous xenograft mouse model.

CONCLUSIONS

F and H proteins of CDV-L co-induce apoptosis in CMT cells, while the NF-κB pathway and fusion activity of F protein paly essential roles in the process.

RCAN1-mediated calcineurin inhibition as a target for cancer therapy

Cancer is the leading cause of mortality worldwide. Regulator of calcineurin 1 (RCAN1), as a patent endogenous inhibitor of calcineurin, plays crucial roles in the pathogenesis of cancers. Except for hypopharyngeal and laryngopharynx cancer, high expression of RCAN1 inhibits tumor progression. Molecular antitumor functions of RCAN1 are largely dependent on calcineurin. In this review, we highlight current research on RCAN1 characteristics, and the interaction between RCAN1 and calcineurin. Moreover, the dysregulation of RCAN1 in various cancers is reviewed, and the potential of targeting RCAN1 as a new therapeutic approach is discussed.

Exploring the Expression of Survivin on Neoadjuvant Chemotherapy in Invasive Breast Carcinoma

Background:   Biomarkers are required to monitor the response to neoadjuvant chemotherapy (NC) in patients with invasive breast cancer (IBC). The purpose of this study is to determine the function of Survivin in the administration of NC, both taxane- and non-taxane-based, to patients with IBC. Methods: Thirty-one samples were categorized according to the NC's administrative status (before or after) and the type of NC used (taxane- or non-taxane-based). Age, tumor grade, receptor status (ER, PR, HER2, Ki-67), and survivin expression were evaluated. Survivin expressions were evaluated by IHC staining and categorized according median H-score cut-offs, while other data were collected from archives. Data was gathered and analyzed using generalized linear model.  Results:  Survivin expression decreased following NC administration, although not significantly (p=0.285). The taxane group had lower survivin expression. Statistically, this was not significant (p=0.329). The non-taxane group had the same outcome (p=0.792). The decline in survivin expression was greater in the taxane group than in the non-taxane group, although it was not statistically significant (p=0.369). Conclusion: Although the changes in survivin expression were not statistically significant, when clinical and laboratory data are analyzed, survivin expression has the potential to be a predictive biomarker of NC response as well as clinical outcome in IBC.

Transcriptional Factor Repertoire of Breast Cancer in 3D Cell Culture Models

Simple Summary

Knowledge of the transcriptional regulation of breast cancer tumorigenesis is largely based on studies performed in two-dimensional (2D) monolayer culture models, which lack tissue architecture and therefore fail to represent tumor heterogeneity. However, three-dimensional (3D) cell culture models are better at mimicking in vivo tumor microenvironment, which is critical in regulating cellular behavior. Hence, 3D cell culture models hold great promise for translational breast cancer research.

Abstract

Intratumor heterogeneity of breast cancer is driven by extrinsic factors from the tumor microenvironment (TME) as well as tumor cell–intrinsic parameters including genetic, epigenetic, and transcriptomic traits. The extracellular matrix (ECM), a major structural component of the TME, impacts every stage of tumorigenesis by providing necessary biochemical and biomechanical cues that are major regulators of cell shape/architecture, stiffness, cell proliferation, survival, invasion, and migration. Moreover, ECM and tissue architecture have a profound impact on chromatin structure, thereby altering gene expression. Considering the significant contribution of ECM to cellular behavior, a large body of work underlined that traditional two-dimensional (2D) cultures depriving cell–cell and cell–ECM interactions as well as spatial cellular distribution and organization of solid tumors fail to recapitulate in vivo properties of tumor cells residing in the complex TME. Thus, three-dimensional (3D) culture models are increasingly employed in cancer research, as these culture systems better mimic the physiological microenvironment and shape the cellular responses according to the microenvironmental cues that will regulate critical cell functions such as cell shape/architecture, survival, proliferation, differentiation, and drug response as well as gene expression. Therefore, 3D cell culture models that better resemble the patient transcriptome are critical in defining physiologically relevant transcriptional changes. This review will present the transcriptional factor (TF) repertoire of breast cancer in 3D culture models in the context of mammary tissue architecture, epithelial-to-mesenchymal transition and metastasis, cell death mechanisms, cancer therapy resistance and differential drug response, and stemness and will discuss the impact of culture dimensionality on breast cancer research.

E-cadherin on epithelial-mesenchymal transition in thyroid cancer

Thyroid carcinoma is a common malignant tumor of endocrine system and head and neck. Recurrence, metastasis and high malignant expression after routine treatment are serious clinical problems, so it is of great significance to explore its mechanism and find action targets. Epithelial-mesenchymal transition (EMT) is associated with tumor malignancy and invasion. One key change in tumour EMT is low expression of E-cadherin. Therefore, this article reviews the expression of E-cadherin in thyroid cancers (TC), discuss the potential mechanisms involved, and outline opportunities to exploit E-cadherin on regulating the occurrence of EMT as a critical factor in cancer therapeutics.

CD95L Inhibition Impacts Gemcitabine-Mediated Effects and Non-Apoptotic Signaling of TNF-α and TRAIL in Pancreatic Tumor Cells

Despite the potential apoptotic functions, the CD95/CD95L system can stimulate survival as well as pro-inflammatory signaling, particularly through the activation of NFκB. This holds true for the TNF/TNFR and the TRAIL/TRAILR systems. Thus, signaling pathways of these three death ligands converge, yet the specific impact of the CD95/CD95L system in this crosstalk has not been well studied. In this study, we show that gemcitabine stimulates the expression of pro-inflammatory cytokines, such as IL6 and IL8, under the influence of the CD95/CD95L system and the pharmacological inhibitor, sCD95Fc, substantially reduced the expression in two PDAC cell lines, PancTuI-luc and A818-4. The stem cell phenotype was reduced when induced upon gemcitabine as well by sCD95Fc. Moreover, TNF-α as well as TRAIL up-regulate the expression of CD95 and CD95L in both cell lines. Conversely, we detected a significant inhibitory effect of sCD95Fc on the expression of both IL8 and IL6 induced upon TNF-α and TRAIL stimulation. In vivo, CD95L inhibition reduced xeno-transplanted recurrent PDAC growth. Thus, our findings indicate that inhibition of CD95 signaling altered the chemotherapeutic effects of gemcitabine, not only by suppressing the pro-inflammatory responses that arose from the CD95L-positive tumor cells but also from the TNF-α and TRAIL signaling in a bi-lateral crosstalk manner.

Reactive oxygen species (ROS) in cancer pathogenesis and therapy: An update on the role of ROS in anticancer action of benzophenanthridine alkaloids

Reactive oxygen species play crucial role in biological homeostasis and pathogenesis of human diseases including cancer. In this line, now it has become evident that ROS level/concentration is a major factor in the growth, progression and stemness of cancer cells. Moreover, cancer cells maintain a delicate balance between ROS and antioxidants to promote pathogenesis and clinical challenges via targeting a battery of signaling pathways converging to cancer hallmarks. Recent findings also entail the therapeutic importance of ROS for the better clinical outcomes in cancer patients as they induce apoptosis and autophagy. Moreover, poor clinical outcomes associated with cancer therapies are the major challenge and use of natural products have been vital in attenuation of these challenges due to their multitargeting potential with less adverse effects. In fact, most available drugs are derived from natural resources, either directly or indirectly and available evidence show the clinical importance of natural products in the management of various diseases, including cancer. ROS play a critical role in the anticancer actions of natural products, particularly phytochemicals. Benzophenanthridine alkaloids of the benzyl isoquinoline family of alkaloids, such as sanguinarine, possess several pharmacological properties and are thus being studied for the treatment of different human diseases, including cancer. In this article, we review recent findings, on how benzophenanthridine alkaloid-induced ROS play a critical role in the attenuation of pathological changes and stemness features associated with human cancers. In addition, we highlight the role of ROS in benzophenanthridine alkaloid-mediated activation of the signaling pathway associated with cancer cell apoptosis and autophagy.

Targeting the mu-Opioid Receptor for Cancer Treatment

PURPOSE OF REVIEW

Opioids are still the most effective and widely used treatments for acute and chronic pain in cancer patients. This review focuses on the impact of opioids and mu-opioid receptors (MOR) on tumor progression and providing new ideas for targeting the MOR in cancer treatment.

RECENT FINDINGS

Studies estimated that opioids facilitate tumor progression and are related to the worse prognosis in cancer patients. As the primary receptor of opioids, MOR is involved in the regulation of malignant transformation of tumors and participating in proliferation, invasion, metastasis, and angiogenesis. MOR may be a new molecular marker of malignant tumors and thus become a new target for cancer therapy, which may be beneficial to the outcomes of cancer patients.

Overexpression of NF-kB as a predictor of neoadjuvant chemotherapy response in breast cancer

BACKGROUND

Cancer cells can defend themselves against apoptosis by activating NF-κB. Nuclear factor-kappa B (NF-κB) activity has also been associated with chemotherapy resistance.

OBJECTIVE

We aimed to investigate the relationship between NF-κB expression and intrinsic subtypes and anthracycline-based neoadjuvant chemotherapy responses in patients with locally advanced breast cancer.

METHODS

This prospective cohort study examined NF-κB expression and intrinsic subtypes of breast cancer tissue using immunohistochemistry (IHC). We conducted descriptive statistical analyses as well as survival analyses.

RESULTS

 The study sample was 63 patients, of which 21 cases (33.33%) were responsive to neoadjuvant chemotherapy, and 42 cases (66.7%) were non-responsive. There is a significant relationship between negative ER, negative PR, grading, and high Ki67 expression with NF-κB overexpression (p < 0.05). No significant relationship was found between intrinsic subtypes and HER2 with NF-κB expression (p > 0.05). A significant relationship was found between NF-κB expression and responsive chemotherapy results (p < 0.01).

CONCLUSION

In locally advanced breast cancer, there is a correlation between NF-B expression and response to anthracycline-based neoadjuvant chemotherapy. Patients who express NF-KB have a better response to chemotherapy than those who overexpress NF-kB.

Mechanisms of Chemopreventive and Therapeutic Proprieties of Ginger Extracts in Cancer

Ginger (Zingiber officinale Roscoe, family: Zingiberaceae), originating in South-East Asia, is one of the most used spices and condiments for foods and beverages. It is also used in traditional medicine for many human disorders including fever, gastrointestinal complications, arthritis, rheumatism, hypertension, and various infectious diseases due to its anti-inflammatory, antioxidant, antimicrobial, and antiemetic properties. Intriguingly, many recent studies evidenced the potent chemopreventive characteristics of ginger extracts against different types of cancer. The aim of this work is to review the literature related to the use of ginger extracts as a chemotherapeutic agent and to structure the cellular and molecular mechanisms through which ginger acts in different cancer types. Data summarized from experiments (in vitro or in vivo) and clinical studies, evidenced in this review, show that ginger derivatives perpetrate its anti-tumor action through important mediators, involved in crucial cell processes, such as cell cycle arrest, induction of cancer cell death, misbalance of redox homeostasis, inhibition of cell proliferation, angiogenesis, migration, and dissemination of cancer cells.

A first-in-class, first-in-human, phase I trial of CIGB-552, a synthetic peptide targeting COMMD1 to inhibit the oncogenic activity of NF-κB in patients with advanced solid tumors

CIGB-552 is a synthetic peptide that interacts with COMMD1 and upregulates its protein levels. The objectives of this phase I study were safety, pharmacokinetic profile, evaluation of the lymphocytes CD4+ and CD8+ and preliminary activity in patients with advanced tumors. A 3 + 3 dose-escalation design with seven dose levels was implemented. Patients were included until a grade 3 related adverse event occurred and the maximum tolerated dose was reached. The patients received subcutaneous administration of CIGB-552 three times per week for 2 weeks. Single-dose plasma pharmacokinetics was characterized at two dose levels, and tumor responses were classified by RECIST 1.1. Twenty-four patients received CIGB-552. Dose-limiting toxicity was associated with a transient grade 3 pruritic maculopapular rash at a dose of 7.0 mg. The maximum tolerated dose was defined as 4.7 mg. Ten patients were assessable for immunological status. Seven patients had significant changes in the ratio CD4/CD8 in response to CIGB-552 treatment; three patients did not modify the immunological status. Stable disease was observed in five patients, including two metastatic soft sarcomas. We conclude that CIGB-552 at dose 4.7 mg was well tolerated with no significant adverse events and appeared to provide some clinical benefits.

The relationship between NFKB, HER2, ER expression and anthracycline -based neoadjuvan chemotherapy response in local advanced stadium breast cancer: A cohort study in Eastern Indonesia

Introduction

Neoadjuvant chemotherapy has become the standard form of treatment for locally advanced breast cancer. Chemoresistence is a problem that limits the effectiveness of chemotherapy. Therefore, predictive biomarkers are needed to choose the appropriate chemotherapy to the right patient. The role of NF-кb expression as a predictive biomarker of neoadjuvant chemotherapy response needs to be investigated in patients with locally advanced breast cancer who are treated with a regimen of cyclophosphamide-doxorubicin-5FU (CAF).

Methods

This observational study used the prospective cohort method to examine 62 samples. CAF was administered at 3-week intervals for 3 cycles of chemotherapy. The data utilized in this study include the positive and negative expression of NF-κB, ER, and HER2 overexpression. The cases were divided into groups that were responsive and non-responsive to the neoadjuvant chemotherapy.

Results

The average age in the youngest group was 26 years, and that in the oldest was 66 years. The highest age group was subjects in their 50s, which had 26 cases (41.9%). The majority of the cases were moderate grade with 38 cases (61.3%). The percentage of responsive subjects was higher in the groups with negative NF-κB expression (82.5%), positive HER2 status (85.7%), and negative ER status (71.9%). It was found that 37 cases (59.7%) were responsive to CAF, while 25 cases (40.3%) were non-responsive. There was a significant relationship between NF-κB expression and chemotherapy response (p < 0.05), and the percentage of responsive subjects was higher among those with negative NF-κB expression (82.5%) than positive NF-κB expression (18.2%).

Conclusion

NF-κB expression, ER status, and HER2 have a significant relationship with the response to anthracycline-based neoadjuvant chemotherapy for local advanced breast cancer, and NF-κB expression has the most significant relationship with the chemotherapy response. Therefore, NF-κB expression should be considered as a predictive biomarker for the response to CAF regimens.

Anti-tumor activity of resveratrol against gastric cancer: a review of recent advances with an emphasis on molecular pathways

Gastric cancer (GC) is one of the most common cancers with high malignancy. In spite of the great development in diagnostic tools and application of anti-tumor drugs, we have not witnessed a significant increase in the survival time of patients with GC. Multiple studies have revealed that Wnt, Nrf2, MAPK, and PI3K/Akt signaling pathways are involved in GC invasion. Besides, long non-coding RNAs and microRNAs function as upstream mediators in GC malignancy. GC cells have acquired resistance to currently applied anti-tumor drugs. Besides, combination therapy is associated with higher anti-tumor activity. Resveratrol (Res) is a non-flavonoid polyphenol with high anti-tumor activity used in treatment of various cancers. A number of studies have demonstrated the potential of Res in regulation of molecular pathways involved in cancer malignancy. At the present review, we show that Res targets a variety of signaling pathways to induce apoptotic cell death and simultaneously, to inhibit the migration and metastasis of GC cells.

Bis-benzylidine Piperidone RA190 treatment of hepatocellular carcinoma via binding RPN13 and inhibiting NF-κB signaling

BACKGROUND

According to GLOBOSCAN, hepatocellular carcinoma (HCC) claimed 782,000 lives in 2018. The tyrosine kinase inhibitor sofafenib is used to treat HCC, but new anticancer agents targeting different pathways are urgently needed to improve outcomes for patients with advanced disease. The aberrant metabolism and aggressive growth of cancer cells can render them particularly susceptible to proteasome inhibition, as demonstrated by bortezomib treatment of multiple myeloma. However, resistance does emerge, and this 20S proteasome inhibitor has not proven active against HCC. The bis-benzylidine piperidone RA190 represents a novel class of proteasome inhibitor that covalently binds to cysteine 88 of RPN13, an ubiquitin receptor subunit of the proteasome's 19S regulatory particle. RA190 treatment inhibits proteasome function, causing rapid accumulation of polyubiquitinated proteins. Considerable evidence suggests that nuclear factor κB (NF-κB) signaling, which is dependent upon the proteasome, is a major driver of inflammation-associated cancers, including HCC.

METHODS

Human HCC cell lines were treated with titrations of RA190. The time course of endoplasmic reticulum stress and NF-κB-related mechanisms by which RA190 may trigger apoptosis were assessed. The therapeutic activity of RA190 was also determined in an orthotopic HCC xenograft mouse model.

RESULTS

RA190 is toxic to HCC cells and synergizes with sofafenib. RA190 triggers rapid accumulation of polyubiquitinated proteins, unresolved endoplasmic reticulum stress, and cell death via apoptosis. RA190 blocks proteasomal degradation of IκBα and consequent release of NF-κB into the nuclei of HCC cells. Treatment of mice bearing an orthotopic HCC model with RA190 significantly reduced tumor growth.

CONCLUSIONS

RA190 has therapeutic activity in a xenograft model, and with sorafenib exhibited synergetic killing of HCC cells in vitro, suggesting further exploration of such a combination treatment of HCC is warranted.

Induction of apoptosis through extrinsic/intrinsic pathways and suppression of ERK/NF-κB signalling participate in anti-glioblastoma of imipramine

Glioblastomas are the most aggressive type of brain tumour, with poor prognosis even after standard treatment such as surgical resection, temozolomide and radiation therapy. The overexpression of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in glioblastomas is recognized as an important treatment target. Thus, an urgent need regarding glioblastomas is the development of a new, suitable agent that may show potential for the inhibition of extracellular signal-regulated kinase (ERK)/NF-κB-mediated glioblastoma progression. Imipramine, a tricyclic antidepressant, has anti-inflammatory actions against inflamed glial cells; additionally, imipramine can induce glioblastoma toxicity via the activation of autophagy. However, whether imipramine can suppress glioblastoma progression via the induction of apoptosis and blockage of ERK/NF-κB signalling remains unclear. The main purpose of this study was to investigate the effects of imipramine on apoptotic signalling and ERK/NF-κB-mediated glioblastoma progression by using cell proliferation (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT] assay), flow cytometry, Western blotting, and cell invasion/migration assay analysis in vitro. The ERK and NF-κB inhibitory capacity of imipramine is detected by NF-κB reporter gene assay and Western blotting. Additionally, a glioblastoma-bearing animal model was used to validate the therapeutic efficacy and general toxicity of imipramine. Our results demonstrated that imipramine successfully triggered apoptosis through extrinsic/intrinsic pathways and suppressed the invasion/migration ability of glioblastoma cells. Furthermore, imipramine effectively suppressed glioblastoma progression in vivo via the inhibition of the ERK/NF-κB pathway. In summary, imipramine is a potential anti-glioblastoma drug which induces apoptosis and has the capacity to inhibit ERK/NF-κB signalling.

Beneficial effect of fluoxetine on anti-tumor progression on hepatocellular carcinoma and non-small cell lung cancer bearing animal model

Fluoxetine, an antidepressant, has been indicated to elicit anti-cancer response in hepatocellular carcinoma (HCC) and non-small cell lung cancer (NSCLC) in vitro. However, anticancer effect and mechanism of fluoxetine in HCC and NSCLC in vivo still needs to be elucidated. In this study, we showed anticancer efficacy and inhibitory mechanism of fluoxetine on the tumor progression of HCC and NSCLC in vivo. Tumor growth was significantly inhibited with fluoxetine treatment in HCC and NSCLC in vivo. Fluoxetine obviously decreased expression of cell proliferative, anti-apoptotic, invasion-associated proteins including Cyclin-D1, survivin, vascular endothelial growth factor (VEGF), matrix metallopeptidase 9 (MMP-9) and urokinase-type plasminogen activator (uPA). Importantly, fluoxetine diminished the phosphorylation of NF-κB p65 which recognized as one of the critical transcription factors in tumor progression. Inhibition of AKT or extracellular signal-regulated kinases (ERK) phosphorylation was linked to NF-κB inactivation in NSCLC or HCC in vitro. Furthermore, expression of AKT or ERK phosphorylation was effectively attenuated by fluoxetine treatment in NSCLC or HCC in vivo. In addition, fluoxetine also triggered extrinsic/intrinsic apoptotic signaling by activating caspase-3, -8, and -9 in HCC and NSCLC. Our findings suggest that fluoxetine may represent as a promising adjuvant for patients with HCC or NSCLC. In conclude, the results also suggested the blockage of AKT/NF-κB or ERK/NF-κB activation and the induction of apoptosis are associated with fluoxetine-inhibited tumor progression of HCC or NSCLC in vivo.

MicroRNA-429 inhibits neuroblastoma cell proliferation, migration and invasion via the NF-κB pathway

Background

MicroRNAs (miRNAs or miRs) can participate in the development and progression of neuroblastoma. Many studies have indicated that miR-429 can participate in tumor development. However, the mechanism underlying miR-429-mediated progression of neuroblastoma remains largely unclear.

Methods

Colony formation and apoptosis assays were used to determine the effect of miR-429 on cell proliferation. Its impact on cell migration was determined using the wound-healing and Transwell assays. The target gene of miR-429 was confirmed via western blotting and luciferase reporter assays. A nude mouse xenograft model with miR-429 overexpression was used to assess the effect on tumor growth.

Results

Our findings indicate that miR-429 is downregulated in neuroblastoma cell lines. We also found that it can induce apoptosis and inhibit proliferation in cells of those lines. MiR-429 can bind to the 3′-UTR of IKKβ mRNA and overexpression of IKKβ can reverse cell proliferation, blocking the effect of miR-429. Furthermore, miR-429 overexpression inhibited neuroblastoma growth in our nude mouse xenograft model.

Conclusion

We provide important insight into miR-429 as a tumor suppressor through interaction with IKKβ, which is a catalytic subunit of the IKK complex that activates NF-κB nuclear transport. Our results demonstrate that miR-429 may be a new target for the treatment of neuroblastoma.

Receptor‑interacting serine/threonine‑protein kinase 1 promotes the progress and lymph metastasis of gallbladder cancer

Receptor-interacting serine/threonine-protein kinase 1 (RIP-1) is highly expressed in gallbladder cancer, and is very important in promoting tumor proliferation and invasion. The underlying mechanism in this promotion is the RIP-1-nuclear factor κ-B (NF-κB) and activator protein 1 (AP-1)-vascular endothelial growth factor-C (VEGF-C) signaling pathways. However, the precise mechanisms by which RIP-1 regulates VEGF-C expression are still unknown. The current study aims to clarify the detailed mechanisms by which RIP-1 upregulates VEGF-C expression. In the current study, the authors constructed various VEGF-C promoter deletions, VEGF-C promoter mutations and RIP-1 overexpression plasmids, and silenced RIP-1 with a small interfering RNA. Promoter analysis, an electrophoretic mobility shift assay, a chromatin immunoprecipitation assay was then performed, and an orthotopic transplantation model in nude mice was established by modified methods previously used. The authors also found that the core region for luciferase activity in the VEGF-C promoter was −332 to −190 nt, in which there are two overlapping AP-1 sites and an NF-κB site. RIP-1 was demonstrated to activate transcription factors NF-κB and AP-1 to combine with the core region and enhance VEGF-C promoter activity. In conclusion, the current study illustrated the mechanisms by which RIP-1 regulates VEGF-C expression, by activating NF-κB and AP-1 to combine with the −332 to −190 nt area of the VEGF-C promoter. By establishing an orthotopic mouse model of gallbladder cancer tumors, it was further elucidated that RIP-1 promotes gallbladder cancer metastasis. The findings provide evidence that targeting RIP-1 may prove to be useful in the treatment of gallbladder cancer.

Clinicopathological significance and prognostic implication of nuclear factor-κB activation in colorectal cancer

OBJECTIVE

The aim of the present study was to evaluate the clinicopathological significance of phosphorylated nuclear factor-κB (pNF-κB) expression, and its impact on epithelial-mesenchymal transition and angiogenesis in colorectal cancer (CRC).

METHODS

We carried out immunohistochemistry of pNF-κB on 261 human CRC tissues, and evaluated nuclear expression, regardless of cytoplasmic expression. We also investigated the correlation between pNF-κB expression and clinicopathological characteristics, survival, and epithelial-mesenchymal transition and angiogenesis-related markers in CRC.

RESULTS

pNF-κB was expressed in the nuclei of 164 of the 261 CRC tissues (62.8%). Furthermore, pNF-κB was significantly correlated with frequent perineural invasion, lymph node metastasis, and higher pTNM stage. However, there was no significant correlation between pNF-κB expression and other clinicopathological parameters. Among the epithelial-mesenchymal transition markers examined, SNAIL expression was significantly correlated with pNF-κB expression (P =  0.001) but E-cadherin expression was not. CRC with pNF-κB expression had significantly higher SIRT1 expression levels and hypoxia-inducible factor-1α expression levels than CRC without pNF-κB expression (P <  0.001 and P <  0.001, respectively). However, there was no correlation between the expression levels of pNF-κB and VEGF. pNF-κB expression was significantly correlated with worse overall and recurrence-free survival rates (P <  0.001 and P <  0.001, respectively).

CONCLUSION

pNF-κB expression was significantly correlated with aggressive tumor behaviors and worse survival rates. Furthermore, pNF-κB expression may affect tumor invasion and progression through SNAIL-related epithelial-mesenchymal transition and SIRT1- and hypoxia-inducible factor-1α-induced angiogenesis.

Amentoflavone Inhibits Hepatocellular Carcinoma Progression Through Blockage of ERK/NF-ĸB Activation

AIM

The aim of the present study was to confirm therapeutic efficacy and find probable mechanism of action of amentoflavone in hepatocellular carcinoma (HCC) in vivo.

MATERIALS AND METHODS

Luciferase reporter vector pGL4.50_transfected SK-Hep1 (SK-Hep1/luc2) tumor-bearing mice were treated with vehicle or amentoflavone (100 mg/kg/day by gavage) for 14 days. Tumor growth, amentoflavone toxicity, and extracellular signal-regulated kinase (ERK)/nuclear factor-kappaB (NF-ĸB) signaling in tumor progression were evaluated with digital caliper, bioluminescence imaging, computed tomography, body weight, pathological examination of liver, and immunohistochemistry staining.

RESULTS

Amentoflavone significantly inhibited tumor growth, ERK/NF-ĸB activation, and expression of tumor progression-associated proteins as compared to vehicle-treated group. In addition, body weight and liver morphology of mice were not influenced by amentoflavone treatment.

CONCLUSION

These results suggest that amentoflavone inhibits HCC progression through suppression of ERK/NF-ĸB signaling.

Prognostic Role of Metastatic Lymph Node Ratio in Papillary Thyroid Carcinoma

Background

The aim of this study is to elucidate the clinicopathological significances, including the prognostic role, of metastatic lymph node ratio (mLNR) and tumor deposit diameter in papillary thyroid carcinoma (PTC) through a retrospective review and meta-analysis.

Methods

We categorized the cases into high (≥ 0.44) and low mLNR (< 0.44) and investigated the correlations with clinicopathological parameters in 64 PTCs with neck level VI lymph node (LN) metastasis. In addition, meta-analysis of seven eligible studies was used to investigate the correlation between mLNR and survival.

Results

Among 64 PTCs with neck level VI LN metastasis, high mLNR was found in 34 PTCs (53.1%). High mLNR was significantly correlated with macrometastasis (tumor deposit diameter ≥ 0.2 cm), extracapsular spread, and number of metastatic LNs. Based on linear regression test, mLNR was significantly increased by the largest LN size but not the largest metastatic LN (mLN) size. High mLNR was not correlated with nuclear factor κB or cyclin D1 immunohistochemical expression, Ki-67 labeling index, or other pathological parameters of primary tumor. Based on meta-analysis, high mLNR significantly correlated with worse disease-free survival at the 5-year and 10-year follow-up (hazard ratio [HR], 4.866; 95% confidence interval [CI], 3.527 to 6.714 and HR, 5.769; 95% CI, 2.951 to 11.275, respectively).

Conclusions

Our data showed that high mLNR significantly correlated with worse survival, macrometastasis, and extracapsular spread of mLNs. Further cumulative studies for more detailed criteria of mLNR are needed before application in daily practice.

NGAL promotes recruitment of tumor infiltrating leukocytes

We have previously shown that Neutrophil Gelatinase-Associated Lipocalin (NGAL) is strongly expressed in thyroid carcinomas, especially of anaplastic type, where it protects neoplastic cells from serum deprivation-induced apoptosis and enhances tumor invasivity by regulating MMP-9 activity. Here we demonstrate that NGAL-containing conditioned medium from human anaplastic thyroid carcinoma (ATC) cells is able to induce monocyte migration via up-regulation of a number of different chemokines. The enhanced chemokines transcription is due to the NGAL-mediated intracellular iron uptake. Very importantly, mice tumor allografts raised from subcutaneous injection of syngeneic colon carcinoma cell lines, expressing high levels of NGAL, show a dense leukocyte infiltrate which strongly decreases in tumor allografts from NGAL-depleted cell injected mice.

Our results indicate that the NGAL promotes leukocytes recruitment in tumor microenvironment through iron-mediated chemokines production.

Resveratrol induces apoptosis in SGC-7901 gastric cancer cells

The aim of the present study was to investigate the effect of resveratrol on apoptosis in SGC-7901 gastric cancer cells and its molecular mechanisms of action. Following resveratrol treatment, the inhibition rate of SGC-7901 cells was determined using an MTT assay. The morphological changes in apoptosis were observed by fluorescence microscopy based on acridine orange/ethidium bromide double staining. Furthermore, cell cycle and apoptosis were detected using flow cytometry, and the expression levels of nuclear factor κB (NF-κB) as well as apoptosis-associated proteins [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), cleaved caspase-3 and cleaved caspase-8] were analyzed by western blotting. The results of the present study indicated that resveratrol was able to significantly inhibit the viability of SGC-7901 cells in a dose- and time-dependent manner. When treated with 200 µM resveratrol, the inhibition rate of SGC-7901 cells reached ~50%. In the presence of resveratrol, the proportion of apoptotic cells was also increased in a dose-dependent manner. Flow cytometry revealed that resveratrol induced S-phase arrest of SGC-7901 cells. When treated with 50, 200 and 400 µM resveratrol, the proportions of SGC-7901 cells in the S-phase were respectively increased to 33.8±2.42, 60.01±2.43 and 56.05±2.67%, compared with 25.62±3.29% for the control group cells in S-phase. Additionally, the levels of the pro-apoptotic proteins Bax, cleaved caspase-3 and cleaved caspase-8 were upregulated in a dose-dependent manner, whereas the level of the anti-apoptotic protein Bcl-2 was downregulated dose-dependently. Importantly, the activation of NF-κB (p65) was evidently decreased following treatment with resveratrol compared with in the control group. In conclusion, the results of the present study revealed that resveratrol was able to inhibit viability and induce apoptosis in SGC-7901 cells by suppressing NF-κB activation. Therefore, resveratrol may be considered as a potential drug candidate for the treatment of gastric cancer.

DEP domain containing 1 suppresses apoptosis via inhibition of A20 expression, which activates the nuclear factor κB signaling pathway in HepG2 cells

A previous study revealed that DEP domain containing 1 (DEPDC1) is involved in the carcinogenesis of bladder cancer via forming a complex with zinc finger protein 224 (ZNF224) to suppress A20 expression, resulting in the activation of the nuclear factor (NF)-κB signaling pathway; however, the role of DEPDC1 in liver cancer remains unclear. Hep G2 cells were treated with 11R-DEP: 611–628, a peptide capable of disrupting the DEPDC1-ZNF224 complex. Cell proliferation was examined using an MTT assay and apoptosis was analyzed via detection of the apoptotic marker caspase-3 using western blot analysis. A20 expression was examined via reverse transcription-quantitative polymerase chain reaction and NF-κB subcellular localization was determined via immunofluorescence staining. microRNA (miR)-130a was overexpressed in HepG2 cells and its effects on proliferation and apoptosis were examined. The results demonstrated that 11R-DEP: 611–628 (3 µM) and miR-130a inhibited cell proliferation and promoted apoptosis in HepG2 cells by activating A20 expression, which blocks the nuclear transportation of NF-κB. In addition, the results demonstrated that the 11R-DEP: 611–628 (3 µM) treatment resulted in downregulation of DEPDC1 expression, indicating that DEPDC1 expression is regulated by the DEPDC1-ZNF224 complex. In conclusion, the data indicated that DEPDC1 suppresses apoptosis to promote cell proliferation through the NF-κB signaling pathway in HepG2 cells and that DEPDC1 is a potential target for the treatment of liver cancer.

The regulator of calcineurin 1 (RCAN1) inhibits nuclear factor kappaB signaling pathway and suppresses human malignant glioma cells growth

Nuclear factor-kappaB (NF-κB) has a vital role in cell survival and inhibition of NF-κB had proven to be an efficient therapeutic pathway for various cancers though little is known about the underlying mechanism. Previously we identified regulator of calcineurin 1 (RCAN1) as an endogenous inhibitor of NF-κB signaling pathway in lymphoma. In the present study, we have solid data to show that RCAN1 can inhibit the nuclear translocation of NF-κB protein then affect the activity of NF-κB signaling pathway in glioma cells. Overexpression of RCAN1 markedly reduced glioma cells viability. We further found that the suppressing glioma cell growth was closely related to the pro-apoptosis effect, not by inhibiting proliferation by the arrest of cell cycle. Our study implicated a novel therapeutic approach for glioma by RCAN1 through inhibition of NF-κB signaling.

PPARγ Ligand-induced Annexin A1 Expression Determines Chemotherapy Response via Deubiquitination of Death Domain Kinase RIP in Triple-negative Breast Cancers

Metastatic breast cancer is still incurable so far; new specifically targeted and more effective therapies for triple-negative breast cancer (TNBC) are required in the clinic. In this study, our clinical data have established that basal and claudin-low subtypes of breast cancer (TNBC types) express significantly higher levels of Annexin A1 (ANXA1) with poor survival outcomes. Using human cancer cell lines that model the TNBC subtype, we observed a strong positive correlation between expression of ANXA1 and PPARγ. A similar correlation between these two markers was also established in our clinical breast cancer patients' specimens. To establish a link between these two markers in TNBC, we show de novo expression of ANXA1 is induced by activation of PPARγ both in vitro and in vivo and it has a predictive value in determining chemosensitivity to PPARγ ligands. Mechanistically, we show for the first time PPARγ-induced ANXA1 protein directly interacts with receptor interacting protein-1 (RIP1), promoting its deubiquitination and thereby activating the caspase-8-dependent death pathway. We further identified this underlying mechanism also involved a PPARγ-induced ANXA1-dependent autoubiquitination of cIAP1, the direct E3 ligase of RIP1, shifting cIAP1 toward proteosomal degradation. Collectively, our study provides first insight for the suitability of using drug-induced expression of ANXA1 as a new player in RIP1-induced death machinery in TNBCs, presenting itself both as an inclusion criterion for patient selection and surrogate marker for drug response in future PPARγ chemotherapy trials. Mol Cancer Ther; 16(11); 2528-42. ©2017 AACR.

The chemokine scavenging receptor D6/ACKR2 is a target of miR-146a in thyroid cancer

We have previously shown that miR-146a, a NF-κB-regulated microRNA, is strongly expressed in human specimens and cell lines derived from anaplastic thyroid carcinomas (ATC) where it mediates some of the NF-κB pro-tumorigenic functions. By using a bioinformatic analysis, we identified the chemokine scavenger receptor D6/ ACKR2 as a target of miR146a in human ATC. We found that the expression of D6/ ACKR2 was up-regulated in miR-146a-null ATC cell lines and that the 3’ UTR of D6/ ACKR2 mRNA was able to inhibit its expression in parental, but not in miR-146a-null ATC cells. Since human specimens from primary ATC showed a low expression of D6/ ACKR2 compared to normal thyroid tissues, we analyzed the effects of D6/ACKR2 over-expression in ATC cells. Different chemokines added to the conditioned medium of D6/ACKR2 over-expressing ATC cells partially failed to drive in vitro monocyte migration, and tumors derived from the injection of the same cells in nude mice showed a decreased number of infiltrating macrophages.

Taken together, these results indicate that ATC cells down-regulate D6/ACKR2 expression through miR-146a activity to sustain leukocyte trafficking inside tumor microenvironment and shed light on a novel mechanism by which NF-κB indirectly inhibits the expression and the function of anti-tumorigenic gene in thyroid cancer.

Regorafenib diminishes the expression and secretion of angiogenesis and metastasis associated proteins and inhibits cell invasion via NF-κB inactivation in SK-Hep1 cells

The aim of the present study was to investigate the effects of regorafenib on the nuclear factor κ-light-chain-enhancer of activated B cells (NF)-κB-modulated expression of angiogenesis- and metastasis-associated proteins and cell invasion in human hepatocellular carcinoma SK-Hep1 cells. The SK-Hep1 cells were treated with different concentrations of NF-κB inhibitor 4-N-[2-(4-phenoxyphenyl) ethyl] quinazoline-4,6-diamine (QNZ) or regorafenib for 24 or 48 h. The effects of QNZ and regorafenib on cell viability, NF-κB activation, expression and secretion levels of angiogenesis- and metastasis-associated proteins and cell invasion were evaluated with MTT assays, western blotting, ELISA, gelatin zymography and cell invasion assays. The results demonstrated that QNZ and regorafenib significantly reduced the expression and secretion levels of the angiogenesis- and metastasis-associated proteins vascular endothelial growth factor, tumor necrosis factor-α, interleukin (IL)-1β, IL-6, matrix metalloproteinase (MMP)-2 and MMP-9, NF-κB activation and cell invasion. In conclusion, the inhibition of NF-κB activation induces anti-angiogenic and antimetastatic effects in SK-Hep1 cells. Regorafenib reduces the level of expression and secretion of angiogenesis- and metastasis-associated proteins and cell invasion through the suppression of NF-κB activation in SK-Hep1 cells.

CUL4A promotes cell invasion in gastric cancer by activating the NF-κB signaling pathway

Cullin 4A (CUL4A) overexpression has been reported to be involved in the carcinogenesis and progression of many malignant tumors. However, the role of CUL4A in the progression of gastric cancer (GC) remains unclear. In this study, we explored whether and how CUL4A regulates proinflammatory signaling to promote GC cell invasion. Our results showed that knockdown of CUL4A inhibited GC cell migration and invasion induced by lipopolysaccharide (LPS) stimulation. We also found that both CUL4A and nuclear factor-kappa B (NF-κB) protein expressions were enhanced by LPS stimulation in HGC27 GC cell lines. Furthermore, knockdown of CUL4A decreased the protein expression of NF-κB and mRNA expression of the downstream genes of the NF-κB pathway, such as matrix metalloproteinase (MMP) 2, MMP9, and interleukin-8. Our immunohistochemistry analysis on 50 GC tissue samples also revealed that CUL4A positively correlated with NF-κB expression. Taken together, our findings suggest that CUL4A may promote GC cell invasion by regulating the NF-κB signaling pathway and could be considered as a potential therapeutic target in patients with GC.

Anti-rheumatic drug iguratimod (T-614) alleviates cancer-induced bone destruction via down-regulating interleukin-6 production in a nuclear factor-κB-dependent manner

Cytokines are believed to be involved in a "vicious circle" of progressive interactions in bone metastasis. Iguratimod is a novel anti-rheumatic drug which is reported to have the capability of anti-cytokines. In this study, a rat model was constructed to investigate the effect of iguratimod on bone metastasis and it was found that iguratimod alleviated cancer-induced bone destruction. To further explore whether an anti-tumor activity of iguratimod contributes to the effect of bone resorption suppression, two human breast cancer cell lines MDA-MB-231 and MCF-7 were studied. The effect of iguratimod on tumor proliferation was detected by CCK-8 assay and flow cytometry. The effects of iguratimod on migration and invasion of cancer cells were determined by wound-healing and Transwell assays. Results showed that high dose (30 μg/mL) iguratimod slightly suppressed the proliferation of cancer cells but failed to inhibit their migration and invasion capacity. Interestingly, iguratimod decreased the transcription level of IL-6 in MDA-MB-231 cells in a concentration-dependent manner. Moreover, iguratimod partially impaired NF-κB signaling by suppressing the phosphorylation of NF-κB p65 subunit. Our findings indicated that iguratimod may alleviate bone destruction by partially decreasing the expression of IL-6 in an NF-κB-dependent manner, while it has little effect on the tumor proliferation and invasion.

The cytokine-cosmc signaling axis upregulates the tumor-associated carbohydrate antigen Tn

Tn antigen (GalNAc-α-O-Ser/Thr), a mucin-type O-linked glycan, is a well-established cell surface marker for tumors and its elevated levels have been correlated with cancer progression and prognosis. There are also reports that Tn is elevated in inflammatory tissues. However, the molecular mechanism for its elevated levels in cancer and inflammation is unclear. In the current studies, we have explored the possibility that cytokines may be one of the common regulatory molecules for elevated Tn levels in both cancer and inflammation. We showed that the Tn level is elevated by the conditioned media of HrasG12V-transformed-BEAS-2B cells. Similarly, the conditioned media obtained from LPS-stimulated monocytes also elevated Tn levels in primary human gingival fibroblasts, suggesting the involvement of cytokines and/or other soluble factors. Indeed, purified inflammatory cytokines such as TNF-α and IL-6 up-regulated Tn levels in gingival fibroblasts. Furthermore, TNF-α was shown to down-regulate the COSMC gene as evidenced by reduced levels of the COSMC mRNA and protein, as well as hypermethylation of the CpG islands of the COSMC gene promoter. Since Cosmc, a chaperone for T-synthase, is known to negatively regulate Tn levels, our results suggest elevated Tn levels in cancer and inflammation may be commonly regulated by the cytokine-Cosmc signaling axis.

NF-κB Mediates the Expression of TBX15 in Cancer Cells

TBX15 is a T-box transcription factor essential for development, also proposed as a marker in prostate cancer; and, recently, its antiapoptotic function indicates a role in carcinogenesis. Regulation of TBX15 is uncovered. In this study, we investigated the regulation of TBX15 expression in human cancer cells, by analyzing the regulatory function of a 5’-distal conserved region of TBX15. Bisulfite sequencing showed high methylation of the CpG island contained in this region that was not correlated with TBX15 mRNA levels, in the cancer cell lines analyzed; however, after 5-aza-dC treatment of TPC-1 cells an increase of TBX15 expression was observed. We also found a significant response of TBX15 to TNF-α activation of the NF-κB pathway using five cancer cell lines, and similar results were obtained when NF-κB was activated with PMA/ionomycin. Next, by luciferase reporter assays, we identified the TBX15 regulatory region containing two functional NF-κB binding sites with response to NF-κBp65, mapping on the -3302 and -3059 positions of the TBX15 gene. Moreover, a direct interaction of NF-κBp65 with one of the two NF-κB binding sites was indicated by ChIP assays. In summary, we provide novel data showing that NF-κB signaling up-regulates TBX15 expression in cancer cells. Furthermore, the link between TBX15 and NF-κB found in this study may be important to understand cancer and development processes.

Elevated NIBP/TRAPPC9 mediates tumorigenesis of cancer cells through NFκB signaling

Regulatory mechanisms underlying constitutive and inducible NFκB activation in cancer remain largely unknown. Here we investigated whether a novel NIK- and IKK2-binding protein (NIBP) is required for maintaining malignancy of cancer cells in an NFκB-dependent manner. Real-time polymerase chain reaction analysis of a human cancer survey tissue-scan cDNA array, immunostaining of a human frozen tumor tissue array and immunoblotting of a high-density reverse-phase cancer protein lysate array showed that NIBP is extensively expressed in most tumor tissues, particularly in breast and colon cancer. Lentivirus-mediated NIBP shRNA knockdown significantly inhibited the growth/proliferation, invasion/migration, colony formation and xenograft tumorigenesis of breast (MDA-MB-231) or colon (HCT116) cancer cells. NIBP overexpression in HCT116 cells promoted cell proliferation, migration and colony formation. Mechanistically, NIBP knockdown in cancer cells inhibited cytokine-induced activation of NFκB luciferase reporter, thus sensitizing the cells to TNFα-induced apoptosis. Endogenous NIBP bound specifically to the phosphorylated IKK2 in a TNFα-dependent manner. NIBP knockdown transiently attenuated TNFα-stimulated phosphorylation of IKK2/p65 and degradation of IκBα. In contrast, NIBP overexpression enhanced TNFα-induced NFκB activation, thus inhibiting constitutive and TNFα-induced apoptosis. Collectively, our data identified important roles of NIBP in promoting tumorigenesis via NFκΒ signaling, spotlighting NIBP as a promising target in cancer therapeutic intervention.

The RCAN1 inhibits NF-κB and suppresses lymphoma growth in mice

Nuclear factor-κB (NF-κB) has a vital role in cell survival. Inhibition of NF-κB has been proven to be an efficient therapeutic pathway for various cancers. Activation of NF-κB is mainly through serine residues' phosphorylation of inhibitor of κBα (IκBα) by IKK complex. Phosphorylation at tyrosine 42 is an alternative pathway in regulation of IκBα and NF-κB signaling, though little is known about the underlying mechanism. Here we identified regulator of calcineurin 1 (RCAN1) as a novel endogenous inhibitor of NF-κB signaling pathway. RCAN1 can interact with IκBα and affect the phosphorylation of IκBα at tyrosine 42. Overexpression of RCAN1 by adenovirus reduced cell viability in lymphoma Raji cells and restrained the growth of lymphoma transplants in mice. We further found that N terminus 1–103aa of RCAN1 is sufficient to inhibit NF-κB and reduce cell viability of lymphoma cells. Our study implicated a novel therapeutic approach for lymphoma by RCAN1 through inhibition of NF-κB signaling.

Expanding the therapeutic spectrum of metformin: from diabetes to cancer

INTRODUCTION

Metformin, an oral hypoglycemic agent, was introduced in the clinical practice for the treatment of type 2 diabetes mellitus more than a half-century ago. Over the years, several studies demonstrated that diabetic patients treated with metformin have a lower incidence of cancer, raising the hypothesis that the spectrum of clinical applications of the drug could be expanded also to cancer therapy. Following these initial findings, a large number of studies were performed aimed at elucidating the effects of metformin on different types of tumor, at explaining its direct and indirect anti-cancer mechanisms and at identifying the molecular pathways targeted by the drug. Several clinical trials were also performed aimed at evaluating the potential anti-cancer effect of metformin among diabetic and non-diabetic patients affected by different types of cancer. While the results of several clinical studies are encouraging, a considerable number of other investigations do not support a role of metformin as an anti-cancer agent, and highlight variables possibly accounting for discrepancies.

AIM

We hereby review the results of in vitro and in vivo studies addressing the issue of the anti-cancer effects of metformin.

CONCLUSIONS

If in vitro data appear solid, the results provided by in vivo studies are somehow controversial. In this view, larger studies are needed to fully elucidate the role of metformin on cancer development and progression, as well as the specific clinical settings in which metformin could become an anti-cancer drug.

Down-regulation of HMGB1 expression by shRNA constructs inhibits the bioactivity of urothelial carcinoma cell lines via the NF-κB pathway

The high mobility group box 1 (HMGB1), which is a highly conserved and evolutionarily non-histone nuclear protein, has been shown to associate with a variety of biological important processes, such as transcription, DNA repair, differentiation, and extracellular signalling. High HMGB1 expression has been reported in many cancers, such as prostate, kidney, ovarian, and gastric cancer. However, there have been few studies of the function of HMGB1 in the malignant biological behaviour of bladder urothelial carcinoma (BUC), and the potential mechanism of HMGB1 in the pathogenesis of BUC remains unclear. Thus, in this study, we constructed plasmid vectors that are capable of synthesizing specific shRNAs targeting HMGB1 and transfected them into BUC cells to persistently suppress the endogenous gene expression of HMGB1. The expression of HMGB1, the bioactivity of BUC cells, including proliferation, apoptosis, cell cycle distribution, migration and invasion, and the effects of HMGB1 knockdown on downstream signalling pathways were investigated. Our data suggest that HMGB1 promotes the malignant biological behaviour of BUC, and that this effect may be partially mediated by the NF-κB signalling pathway. HMGB1 may serve as a potential therapeutic target for BUC in the future.

Aberrant MEK5/ERK5 signalling contributes to human colon cancer progression via NF-κB activation

This study was designed to evaluate MEK5 and ERK5 expression in colon cancer progression and to ascertain the relevance of MEK5/ERK5 signalling in colon cancer. Expression of MEK5 and ERK5 was evaluated in 323 human colon cancer samples. To evaluate the role of MEK5/ERK5 signalling in colon cancer, we developed a stable cell line model with differential MEK5/ERK5 activation. Impact of differential MEK5/ERK5 signalling was evaluated on cell cycle progression by flow cytometry and cell migration was evaluated by wound healing and transwell migration assays. Finally, we used an orthotopic xenograft mouse model of colon cancer to assess tumour growth and progression. Our results demonstrated that MEK5 and ERK5 are overexpressed in human adenomas (P<0.01) and adenocarcinomas (P<0.05), where increased ERK5 expression correlated with the acquisition of more invasive and metastatic potential (P<0.05). Interestingly, we observed a significant correlation between ERK5 expression and NF-κB activation in human adenocarcinomas (P<0.001). We also showed that ERK5 overactivation significantly accelerated cell cycle progression (P<0.05) and increased cell migration (P<0.01). Furthermore, cells with overactivated ERK5 displayed increased NF-κB nuclear translocation and transcriptional activity (P<0.05), together with increased expression of the mesenchymal marker vimentin (P<0.05). We further demonstrated that increased NF-κB activation was associated with increased IκB phosphorylation and degradation (P<0.05). Finally, in the mouse model, lymph node metastasis was exclusively seen in orthotopically implanted tumours with overactivated MEK5/ERK5, and not in tumours with inhibited MEK5/ERK5. Our results suggested that MEK5/ERK5/NF-κB signalling pathway is important for tumour onset, progression and metastasis, possibly representing a novel relevant therapeutic target in colon cancer treatment.

Characteristics of neck level VI lymph nodes in papillary thyroid carcinoma: correlation between nodal characteristics and primary tumor

Little is known about the pathological characteristics of metastatic and nonmetastatic lymph nodes (LNs) in papillary thyroid carcinoma (PTC). The aim of this study was to elucidate the pathological characteristics of neck level VI nodes and correlations with clinicopathological parameters. We investigated the clinicopathological features of 124 classical PTCs and characteristics of 850 dissected neck level VI LNs. Immunohistochemistry for nuclear factor-κB (NF-κB) and Ki-67 was performed on primary tumors, and correlations with nodal characteristics were investigated. Nodal metastasis at neck level VI was identified in 68 of 124 PTCs (54.8 %) and was significantly correlated with tumor size, tumor multifocality, extrathyroidal extension, and tumor stage. LN metastasis was significantly correlated with larger mean LN size (P < 0.001), larger size of the largest LN (P < 0.001), and more LNs (P < 0.001). The mean size of metastatic LNs (n = 233) was significantly larger than nonmetastatic LNs (n = 617) (P < 0.001). Primary tumor diameter significantly correlated with the largest LN size (P = 0.014, R (2) = 0.049), but not mean size or number of LNs by linear regression analysis. NF-κB and Ki-67 proliferation indexes were not significantly correlated with larger nodal size. These results suggested that characteristics of nodes and primary tumor would be useful criteria for making decisions about preoperative surveillance of nodal metastasis.

Sources of dynamic variability in NF-κB signal transduction: a mechanistic model

The transcription factor NF-κB (p65/p50) plays a central role in the coordination of cellular responses by activating the transcription of numerous target genes. The precise role of the dynamics of NF-κB signalling in regulating gene expression is still an open question. Here, we show that besides external stimulation intracellular parameters can influence the dynamics of NF-κB. By applying mathematical modelling and bifurcation analyses, we show that NF-κB is capable of exhibiting different types of dynamics in response to the same stimulus. We identified the total NF-κB concentration and the IκBα transcription rate constant as two critical parameters that modulate the dynamics and the fold change of NF-κB. Both parameters might vary as a result of cell-to-cell variability. The regulation of the IκBα transcription rate constant, e.g. by co-factors, provides the possibility of regulating the NF-κB dynamics by crosstalk.

Withaferin A disrupts ubiquitin-based NEMO reorganization induced by canonical NF-κB signaling

The NF-κB family of transcription factors regulates numerous cellular processes, including cell proliferation and survival responses. The constitutive activation of NF-κB has also emerged as an important oncogenic driver in many malignancies, such as activated B-cell like diffuse large B cell lymphoma, among others. In this study, we investigated the impact and mechanisms of action of Withaferin A, a naturally produced steroidal lactone, against both signal-inducible as well as constitutive NF-κB activities. We found that Withaferin A is a robust inhibitor of canonical and constitutive NF-κB activities, leading to apoptosis of certain lymphoma lines. In the canonical pathway induced by TNF, Withaferin A did not disrupt RIP1 polyubiquitination or NEMO-IKKβ interaction and was a poor direct IKKβ inhibitor, but prevented the formation of TNF-induced NEMO foci which colocalized with TNF ligand. While GFP-NEMO efficiently formed TNF-induced foci, a GFP-NEMO(Y308S) mutant that is defective in binding to polyubiquitin chains did not form foci. Our study reveals that Withaferin A is a novel type of IKK inhibitor which acts by disrupting NEMO reorganization into ubiquitin-based signaling structures in vivo.

Immunohistochemical evaluation of midkine and nuclear factor-kappa B as diagnostic biomarkers for papillary thyroid cancer and synchronous metastasis

AIMS

Midkine (MK) is a multifunctional cytokine identified to be a promising cancer biomarker. Nuclear factor-kappa B (NF-κB) is an important transcription factor that plays a pivotal role in tumorigenesis. We aimed to investigate values of MK and NF-κB as markers for diagnosis and synchronous metastasis prediction in papillary thyroid cancer (PTC).

MAIN METHODS

76 cases of PTC and 70 cases of multi-nodular goiter (MNG) were retrieved. The PTC group was further divided into subgroup 1 (16 cases with synchronous metastases) and subgroup 2 (60 cases without metastases). A retrospective review of demographic and clinical information was performed. Immunohistochemistry of MK, NF-κB p65 and Ki-67 was performed on paraffin-embedded specimens and results were quantified. Diagnostic values of the parameters were conducted by receiver operating characteristic (ROC) curves. Protein levels of MK and NF-κB p65 were then confirmed by Western blot.

KEY FINDINGS

Immunoreactivities of MK, NF-κB p65 and Ki-67 were significantly higher in the PTC group than in the MNG group with good differential diagnostic capabilities. Moreover, immunoreactivities of all three parameters were significantly higher in subgroup 1 than in subgroup 2 with good synchronous metastasis predictive efficacies. Western blot showed that MK and NF-κB p65 protein levels in lesions from subgroup 1 were significantly higher than those from subgroup 2, both of which were significantly higher than in MNG lesions.

SIGNIFICANCE

We discovered that MK and NF-κB immunohistochemistries can potentially be used for differential diagnosis between PTC and MNG, and for prediction of synchronous metastases.

Inhibition of NF-kappa B signaling restores responsiveness of castrate-resistant prostate cancer cells to anti-androgen treatment by decreasing androgen receptor-variant expression

Androgen receptor splicing variants (ARVs) that lack the ligand-binding domain (LBD) are associated with the development of castration-resistant prostate cancer (CRPC), including resistance to the new generation of high-affinity anti-androgens. However, the mechanism by which ARV expression is regulated is not fully understood. In this study, we show that the activation of classical nuclear factor-kappa B (NF-κB) signaling increases the expression of ARVs in prostate cancer (PCa) cells and converts androgen-sensitive PCa cells to become androgen-insensitive, whereas downregulation of NF-κB signaling inhibits ARV expression and restores responsiveness of CRPC to anti-androgen therapy. In addition, we demonstrated that combination of anti-androgen with NF-κB-targeted therapy inhibits efficiently tumor growth of human CRPC xenografts. These results indicate that induction of ARVs by activated NF-κB signaling in PCa cells is a critical mechanism by which the PCa progresses to CRPC. This has important implications as it can prolong the survival of CRPC patients by restoring the tumors to once again respond to conventional androgen-deprivation therapy (ADT).

Cytoplasmic TRADD confers a worse prognosis in glioblastoma

Tumor necrosis factor receptor 1 (TNFR1)-associated death domain protein (TRADD) is an important adaptor in TNFR1 signaling and has an essential role in nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation and survival signaling. Increased expression of TRADD is sufficient to activate NF-κB. Recent studies have highlighted the importance of NF-κB activation as a key pathogenic mechanism in glioblastoma multiforme (GBM), the most common primary malignant brain tumor in adults.We examined the expression of TRADD by immunohistochemistry (IHC) and find that TRADD is commonly expressed at high levels in GBM and is detected in both cytoplasmic and nuclear distribution. Cytoplasmic IHC TRADD scoring is significantly associated with worse progression-free survival (PFS) both in univariate and multivariate analysis but is not associated with overall survival (n = 43 GBMs). PFS is a marker for responsiveness to treatment. We propose that TRADD-mediated NF-κB activation confers chemoresistance and thus a worse PFS in GBM. Consistent with the effect on PFS, silencing TRADD in glioma cells results in decreased NF-κB activity, decreased proliferation of cells, and increased sensitivity to temozolomide. TRADD expression is common in glioma-initiating cells. Importantly, silencing TRADD in GBM-initiating stem cell cultures results in decreased viability of stem cells, suggesting that TRADD may be required for maintenance of GBM stem cell populations. Thus, our study suggests that increased expression of cytoplasmic TRADD is both an important biomarker and a key driver of NF-κB activation in GBM and supports an oncogenic role for TRADD in GBM.

MicroRNA-362 induces cell proliferation and apoptosis resistance in gastric cancer by activation of NF-κB signaling

Background

According to cancer-related microRNA (miRNA) expression microarray research available in public databases, miR-362 expression is elevated in gastric cancer. However, the expression and biological role of miR-362 in gastric progression remain unclear.

Methods

miR-362 expression levels in gastric cancer tissues and cell lines were determined using real-time PCR. The roles of miR-362, in promoting gastric cancer cell proliferation and apoptosis resistance, were assessed by different biological assays, such as colony assay, flow cytometry and TUNEL assay. The effect of miR-362 on NF-κB activation was investigated using the luciferase reporter assay, fluorescent immunostaining.

Results

MiR-362 overexpression induced cell proliferation, colony formation, and resistance to cisplatin-induced apoptosis in BGC-823 and SGC-7901 gastric cancer cells. MiR-362 increased NF-κB activity and relative mRNA expression of NF-κB–regulated genes, and induced nuclear translocation of p65. Expression of the tumor suppressor CYLD was inhibited by miR-362 in gastric cancer cells; miR-362 levels were inversely correlated with CYLD expression in gastric cancer tissue. MiR-362 downregulated CYLD expression by binding its 3′ untranslated region. NF-κB activation was mechanistically associated with siRNA-mediated downregulation of CYLD. MiR-362 inhibitor reversed all the effects of miR-362.

Conclusion

The results suggest that miR-362 plays an important role in repressing the tumor suppressor CYLD and present a novel mechanism of miRNA-mediated NF-κB activation in gastric cancer.