Function of phosphorylation of NF-kB p65 ser536 in prostate cancer oncogenesis

Bioinformatics analyses of combined databases identify shared differentially expressed genes in cancer and autoimmune disease

BACKGROUND

Inadequate immunity caused by poor immune surveillance leads to tumorigenesis, while excessive immunity due to breakdown of immune tolerance causes autoimmune genesis. Although the function of immunity during the onset of these two processes appears to be distinct, the underlying mechanism is shared. To date, gene expression data for large bodies of clinical samples are available, but the resemblances of tumorigenesis and autoimmune genesis in terms of immune responses remains to be summed up.

METHODS

Considering the high disease prevalence, we chose invasive ductal carcinoma (IDC) and systemic lupus erythematosus (SLE) to study the potential commonalities of immune responses. We obtained gene expression data of IDC/SLE patients and normal controls from five IDC databases (GSE29044, GSE21422, GSE22840, GSE15852, and GSE9309) and five SLE databases (GSE154851, GSE99967, GSE61635, GSE50635, and GSE17755). We intended to identify genes differentially expressed in both IDC and SLE by using three bioinformatics tools including GEO2R, the limma R package, and Weighted Gene Co-expression Network Analysis (WGCNA) to perform function enrichment, protein-protein network, and signaling pathway analyses.

RESULTS

The mRNA levels of signal transducer and activator of transcription 1 (STAT1), 2'-5'-oligoadenylate synthetase 1 (OAS1), 2'-5'-oligoadenylate synthetase like (OASL), and PML nuclear body scaffold (PML) were found to be differentially expressed in both IDC and SLE by using three different bioinformatics tools of GEO2R, the limma R package and WGCNA. From the combined databases in this study, the mRNA levels of STAT1 and OAS1 were increased in IDC while reduced in SLE. And the mRNA levels of OASL and PML were elevated in both IDC and SLE. Based on Kyoto Encyclopedia of Genes and Genomes pathway analysis and QIAGEN Ingenuity Pathway Analysis, both IDC and SLE were correlated with the changes of multiple components involved in the Interferon (IFN)-Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway.

CONCLUSION

The expression levels of STAT1 and OAS1 manifest the opposite expression tendency across cancer and autoimmune disease. They are components in the IFN-JAK-STAT signaling pathway related to both tumorigenesis and autoimmune genesis. STAT1 and OAS1-associated IFN-JAK-STAT signaling could explain the commonalities during tumorigenesis and autoimmune genesis and render significant information for more precise treatment from the point of immune homeostasis.

Effect of regulatory cell death on the occurrence and development of head and neck squamous cell carcinoma

Head and neck cancer is a malignant tumour with a high mortality rate characterized by late diagnosis, high recurrence and metastasis rates, and poor prognosis. Head and neck squamous cell carcinoma (HNSCC) is the most common type of head and neck cancer. Various factors are involved in the occurrence and development of HNSCC, including external inflammatory stimuli and oncogenic viral infections. In recent years, studies on the regulation of cell death have provided new insights into the biology and therapeutic response of HNSCC, such as apoptosis, necroptosis, pyroptosis, autophagy, ferroptosis, and recently the newly discovered cuproptosis. We explored how various cell deaths act as a unique defence mechanism against cancer emergence and how they can be exploited to inhibit tumorigenesis and progression, thus introducing regulatory cell death (RCD) as a novel strategy for tumour therapy. In contrast to accidental cell death, RCD is controlled by specific signal transduction pathways, including TP53 signalling, KRAS signalling, NOTCH signalling, hypoxia signalling, and metabolic reprogramming. In this review, we describe the molecular mechanisms of nonapoptotic RCD and its relationship to HNSCC and discuss the crosstalk between relevant signalling pathways in HNSCC cells. We also highlight novel approaches to tumour elimination through RCD.

Biological relevance of ZNF224 expression in chronic lymphocytic leukemia and its implication IN NF-kB pathway regulation

Chronic lymphocytic leukemia (CLL) is a heterogeneous disease, whose presentation and clinical course are highly variable. Identification of novel prognostic factors may contribute to improving the CLL classification and providing indications for treatment options. The zinc finger protein ZNF224 plays a key role in cell transformation, through the control of apoptotic and survival pathways. In this study, we evaluated the potential application of ZNF224 as a novel marker of CLL progression and therapy responsiveness. To this aim, we analyzed ZNF224 expression levels in B lymphocytes from CLL patients at different stages of the disease and in patients showing different treatment outcomes. The expression of ZNF224 was significantly increased in disease progression and dramatically decreased in patients in complete remission after chemotherapy. Gene expression correlation analysis performed on datasets of CLL patients revealed that ZNF224 expression was well correlated with that of some prognostic and predictive markers. Moreover, bioinformatic analysis coupled ZNF224 to NF-κB pathway, and experimental data demonstrated that RNA interference of ZNF224 reduced the activity of the NF-κB survival pathway in CLL cells. Consistently with a pro-survival role, ZNF224 knockdown raised spontaneous and drug-induced apoptosis and inhibited the proliferation of peripheral blood mononuclear cells from CLL patients. Our findings provide evidence for the involvement of ZNF224 in the survival of CLL cells via NF-κB pathway modulation, and also suggest ZNF224 as a prognostic and predictive molecular marker of CLL disease.

Drivers of Radioresistance in Prostate Cancer

Prostate cancer (PCa) is the second most commonly diagnosed cancer worldwide. Radiotherapy remains one of the first-line treatments in localised disease and may be used as monotherapy or in combination with other treatments such as androgen deprivation therapy or radical prostatectomy. Despite advancements in delivery methods and techniques, radiotherapy has been unable to totally overcome radioresistance resulting in treatment failure or recurrence of previously treated PCa. Various factors have been linked to the development of tumour radioresistance including abnormal tumour vasculature, oxygen depletion, glucose and energy deprivation, changes in gene expression and proteome alterations. Understanding the biological mechanisms behind radioresistance is essential in the development of therapies that are able to produce both initial and sustained response to radiotherapy. This review will investigate the different biological mechanisms utilised by PCa tumours to drive radioresistance.

Past, Current, and Future Strategies to Target ERG Fusion-Positive Prostate Cancer

Simple Summary

In addition to its role in development and in the vascular and hematopoietic systems, ERG plays a central role in prostate cancer. Approximately 40–50% of prostate cancer cases are characterized by ERG gene fusions, which lead to ERG overexpression. Importantly, inhibition of ERG activity in prostate cancer cells decreases their viability. Therefore, inhibiting ERG might represent an important step to improve treatment efficacy for patients with ERG-positive prostate tumors. Here, we summarize the attempts made over the past years to repress ERG activity, the current use of ERG fusion detection and the strategies that might be utilized in the future to treat ERG fusion-positive tumors.

Abstract

The ETS family member ERG is a transcription factor with physiological roles during development and in the vascular and hematopoietic systems. ERG oncogenic activity characterizes several malignancies, including Ewing’s sarcoma, leukemia and prostate cancer (PCa). In PCa, ERG rearrangements with androgen-regulated genes—mostly TMPRSS2—characterize a large subset of patients across disease progression and result in androgen receptor (AR)-mediated overexpression of ERG in the prostate cells. Importantly, PCa cells overexpressing ERG are dependent on ERG activity for survival, further highlighting its therapeutic potential. Here, we review the current understanding of the role of ERG and its partners in PCa. We discuss the strategies developed in recent years to inhibit ERG activity, the current therapeutic utility of ERG fusion detection in PCa patients, and the possible future approaches to target ERG fusion-positive tumors.

The Metastasis Suppressor NDRG1 Directly Regulates Androgen Receptor Signaling in Prostate Cancer

N-myc-downregulated gene 1 (NDRG1) has potent anticancer effects and inhibits cell growth, survival, metastasis, and angiogenesis. Previous studies suggested that NDRG1 is linked to the androgen signaling network, but this mechanistic relationship is unclear. Considering the crucial role of the androgen receptor (AR) in prostate cancer (PCa) progression, here we examined for the first time the effect of NDRG1 on AR expression, activation, and downstream signaling in LNCaP, 22Rv1, and C4-2B PCa cell types. We demonstrate that NDRG1 effectively promotes interaction of AR with the chaperone HSP90, which in turn stabilizes the AR while decreasing its androgen-mediated activation. The expression of NDRG1 suppressed: (1) AR activation, as measured by p-AR^Ser213 and p-AR^Ser81; (2) expression of a major AR transcriptional target, prostate-specific antigen (PSA); and (3) AR transcriptional activity, probably via inhibiting the c-Jun-AR interaction by reducing c-Jun phosphorylation (p-c-Jun^Ser63). NDRG1 was also demonstrated to inhibit multiple key molecules involved in androgen-dependent and -independent signaling (namely EGFR, HER2, HER3, PI3K, STAT3, and NF-κB), which promote the development of castration-resistant prostate cancer. We also identified the cysteine-rich secretory protein/antigen 5/pathogenesis related-1 (CAP) domain of NDRG1 as vital for inhibition of AR activity. Examining NDRG1 and p-NDRG1 in PCa patient specimens revealed a significant negative correlation between NDRG1 and PSA levels in prostatectomy patients that went on to develop metastasis. These results highlight a vital role for NDRG1 in androgen signaling and its potential as a key therapeutic target and biomarker in PCa.

MEX3D is an oncogenic driver in prostate cancer

BACKGROUND

Prostate cancer (PCa) is the most common visceral malignancy and the second leading cause of cancer deaths in US men. The two most common genetic alterations in PCa are expression of the TMPRSS2/ERG (TE) fusion gene and loss of the PTEN tumor suppressor. These genetic alterations act cooperatively to transform prostatic epithelium but the exact mechanisms involved are unclear.

METHODS

Microarray expression analysis of immortalized prostate epithelial cells transformed by loss of PTEN and expression of the TE fusion revealed MEX3D as one of the most highly upregulated genes. MEX3D expression in prostate cancer was examined in patient samples and in silico. In vitro and in vivo studies to characterize the biological impact of MEX3D were carried out. Analysis of the TCGA PanCancer database revealed TCF3 as a major target of MEX3D. The induction of TCF3 by MEX3D was confirmed and the biological impact of TCF3 examined by in vitro studies.

RESULTS

MEX3D is expressed at increased levels in prostate cancer and is increased by decreased PTEN and/or expression of the TE fusion gene and drives soft agar colony formation, invasion and tumor formation in vivo. The known oncogenic transcription factor TCF3 is highly correlated with MEX3D in prostate cancer. MEX3D expression strongly induces TCF3, which promotes soft agar colony formation and invasion in vitro.

CONCLUSIONS

Loss of PTEN and expression of the TE fusion gene in prostate cancer strongly upregulates expression of MEX3D and its target TCF3 and promotes transformation associated phenotypes via this pathway.

MEST promotes lung cancer invasion and metastasis by interacting with VCP to activate NF-κB signaling

Background

Cell invasion is a hallmark of metastatic cancer, leading to unfavorable clinical outcomes. In this study, we established two highly invasive lung cancer cell models (A549-i8 and H1299-i8) and identified mesoderm-specific transcript (MEST) as a novel invasive regulator of lung cancer. We aim to characterize its biological function and clinical significance in lung cancer metastasis.

Methods

Transwell invasion assay was performed to establish high-invasive lung cancer cell model. Immunohistochemistry (IHC) was used to detect MEST expression in tumor tissues. Mass spectrometry and bioinformatic analyses were used to identify MEST-regulated proteins and binding partners. Co-immunoprecipitation assay was performed to detect the interaction of MEST and VCP. The biological functions of MEST were investigated in vitro and in vivo. Immunofluorescence staining was conducted to explore the colocalization of MEST and VCP.

Results

MEST overexpression promoted metastasis of lung cancer cells in vivo and in vitro by activating NF-κB signaling. MEST increased the interaction between VCP and IκBα, which accelerated IκBα degradation and NF-κB activation. Such acceleration was abrogated by VCP silencing, indicating that MEST is an upstream activator of the VCP/IκBα/NF-κB signaling pathway. Furthermore, high expressions of MEST and VCP were associated with poor survival of lung cancer patients.

Conclusion

Collectively, these results demonstrate that MEST plays an important role in driving invasion and metastasis of lung cancer by interacting with VCP to coordinate the IκBα/NF-κB pathway. Targeting the MEST/VCP/IκBα/NF-κB signaling pathway may be a promising strategy to treat lung cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02107-1.

Measuring NF-κB Phosphorylation and Acetylation

Posttranslational modifications of NF-κB, including phosphorylation, acetylation, and methylation, have emerged as important regulatory mechanisms to control the transcriptional outcomes of this important transcription factor. These modifications work independently, sequentially or in combination to modulate the diverse biological functions of NF-κB in cancer and inflammatory response. Here, we describe some experimental methods to detect the in vitro and in vivo phosphorylation and acetylation of NF-κB, specifically focusing on the RelA subunit of NF-κB. These methods include labeling the phospho- or acetyl- groups with radioisotopes in vitro and immunoblotting with site-specific anti-phospho-serine or acetyl-lysine antibodies in culture cells and tissue samples.

Roles of long noncoding RNAs on tumor immune escape by regulating immune cells differentiation and function

A long noncoding RNA (lncRNA) transcript is generally more than 200 nucleotides in length and rarely codes for any protein. Currently, many lncRNAs have been identified among mammalian genomes, and their known functions are associated with various physiological activities or pathological processes. Some lncRNAs are dysregulated in a variety of malignant tumors, while increasing evidence indicates that abnormal expression can contribute to the regulation of immune cells in tumors and to shaping the immune response. More specifically, lncRNAs participate in regulating the differentiation of immune cells, also known as myeloid and lymphoid cells, as well as recruiting various immunosuppressive factors to influence the tumor microenvironment, thereby promoting tumor cell immune escape. However, we still know very little about the specific mechanism of lncRNAs in immune escape of cancer. Nonetheless, although unprecedented achievements have allowed the development of a new generation of anti-tumor immune therapies to be applied in clinical trials, the drug resistance caused by immune escape has become a major clinical challenge. The focus of this review is to describe the relationship among lncRNAs, immune cells, and tumor immune escape, in order to identify novel diagnostic and therapeutic targets in human cancers.

Phosphorylation of the Regulators, a Complex Facet of NF-κB Signaling in Cancer

The nuclear factor kappa B (NF-κB) is a ubiquitous transcription factor central to inflammation and various malignant diseases in humans. The regulation of NF-κB can be influenced by a myriad of post-translational modifications (PTMs), including phosphorylation, one of the most popular PTM formats in NF-κB signaling. The regulation by phosphorylation modification is not limited to NF-κB subunits, but it also encompasses the diverse regulators of NF-κB signaling. The differential site-specific phosphorylation of NF-κB itself or some NF-κB regulators can result in dysregulated NF-κB signaling, often culminating in events that induce cancer progression and other hyper NF-κB related diseases, such as inflammation, cardiovascular diseases, diabetes, as well as neurodegenerative diseases, etc. In this review, we discuss the regulatory role of phosphorylation in NF-κB signaling and the mechanisms through which they aid cancer progression. Additionally, we highlight some of the known and novel NF-κB regulators that are frequently subjected to phosphorylation. Finally, we provide some future perspectives in terms of drug development to target kinases that regulate NF-κB signaling for cancer therapeutic purposes.

Long Non-Coding RNA NKILA Reduces Oral Squamous Cell Carcinoma Development Through the NF-KappaB Signaling Pathway

Objective:

Emerging studies have identified that long non-coding RNAs (lncRNAs) play critical roles in cancer development. This study aims to explore the mechanism of NF-KappaB (NF-κB) interacting lncRNA (NKILA) in the pathological process of oral squamous cell carcinoma (OSCC).

Methods:

NKILA expression in OSCC tissues, paracancerous tissues, and normal human oral keratinocytes and OSCC cell lines was detected using RT-qPCR. KB cells were selected for the follow-up experiments. The role of NKILA in cell proliferation, migration, invasion, and NF-κB signaling pathway was identified using the gain- and loss-of function of NKILA in OSCC cells. Additionally, the role of NKILA in vitro was determined by inducing xenograft tumors in nude mice.

Results:

NKILA was poorly expressed in OSCC tissues and cells. Cell proliferation, invasion and migration, tumor volume and weight were significantly suppressed in cells with overexpressed NKILA, while silencing NKILA led to opposite trends. Moreover, the protein levels of p-IκBα and nuclear-p65 were markedly decreased, while the levels of IκBα and cytoplasm-p65 were enhanced in cells with overexpressed NKILA.

Conclusion:

This study provided evidence that NKILA could reduce proliferation, invasion and migration of OSCC cells through inhibiting the NF-κB signaling pathway. The findings may offer new insights for OSCC prevention and treatment.

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.

MiR-1307-5p targeting TRAF3 upregulates the MAPK/NF-κB pathway and promotes lung adenocarcinoma proliferation

BACKGROUND

Non-small cell lung cancer (NSCLC) includes lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). MicroRNA (miRNA) plays an important role in the regulation of post-transcriptional gene expression in animals and plants, especially in lung adenocarcinoma.

METHODS

MiR-1307-5p is an miRNA with significant differences screened by the second generation of high-throughput sequencing in the early stage of our research group. In the current study, a series of in vitro and in vivo experiments were carried out. MiR-1307-5p mimic, miR-1307-5p inhibitor, and NC were transfected into A549 and H1299 lung adenocarcinoma cells. The correlation between miR-1307-5p and clinicopathological features in pathological samples was analyzed using a lung adenocarcinoma tissue microarray, and miR-1307-5p expression was detected by qPCR. CCK-8, EdU, colony formation, scratch test, and Transwell assays were used to observe cell proliferation and migration. Double luciferase assay, western blot, qPCR, and immunohistochemistry were employed in confirming the target relationship between miR-1307-5p and TRAF3. Western blotting was used to analyze the relationship between miR-1307-5p and the NF-κB/MAPK pathway. Finally, the effect of miR-1307-5p on tumor growth was studied using a subcutaneous tumorigenesis model in nude mice.

RESULTS

Increased miR-1307-5p expression was significantly related to decreased overall survival rate of lung adenocarcinoma patients, revealing miR-1307-5p as a potential oncogene in lung adenocarcinoma. MiR-1307-5p mimic significantly promoted while miR-1307-5p inhibitor reduced the growth and proliferation of A549 and H1299 cells. MiR-1307-5p overexpression significantly enhanced the migration ability while miR-1307-5p inhibition reduced the migration ability of A549 and H1299 cells. Target binding of miR-1307-5p to TRAF3 was confirmed by double luciferase assay, western blot, qPCR, and immunohistochemistry. miR-1307-5p caused degradation of TRAF3 mRNA and protein. MiR-1307-5p targeted TRAF3 and activated the NF-κB/MAPK pathway. TRAF3 colocalized with p65 and the localization of TRAF3 and p65 changed in each treatment group. Tumor volume of the lv-miR-1307-5p group was significantly larger than that of the lv-NC group, and that of the lv-miR-1307-5p-inhibitor group was significantly smaller than that of the lv-NC group.

CONCLUSION

In conclusion, miR-1307-5p targets TRAF3 and activates the NF-κB/MAPK pathway to promote proliferation in lung adenocarcinoma.

miR-20b-5p attenuates hypoxia-induced apoptosis in cardiomyocytes via the HIF-1α/NF-κB pathway

Chronic hypoxia is a common inducer of end-stage cardiovascular disease. In cells under hypoxia, the hypoxia-inducible factor-1 (HIF-1) plays a vital role in regulating downstream target genes. However, the mechanism of hypoxia in cardiomyocytes is still unclear. In this study, we aimed to identify novel downstream epigenetic targets of HIF-1α in cardiomyocytes under hypoxia. H9c2 cells were exposed to hypoxia condition, and quantitative real-time PCR analysis was performed to evaluate the expression of miR-20b-5p. The results indicated that the expression of miR-20b-5p was down-regulated in H9c2 cells under low oxygen condition. Meanwhile, HIF-1α overexpression further down-regulated the miR-20b-5p expression in H9c2 cells transfected with HIF-1α plasmids. In addition, Annexin-V-FITC/PI flow cytometry analysis suggested that overexpression of miR-20b-5p attenuated cell apoptosis under hypoxia condition in H9c2 cells. Western blot analysis showed that the hypoxia apparently increased Bax and cleaved-caspase-3, but decreased Bcl-2 expression in H9c2 cells, indicating that hypoxia-induced NF-κB signaling pathway activation is mediated by miR-20b-5p. Hypoxia-induced H9c2 cell apoptosis was reduced after HIF-1α knockdown as shown by the flow cytometry analysis. In conclusion, we identified that miR-20b-5p plays an important role in mediating cardiomyocytes apoptosis under hypoxia, which is mediated by the HIF-1/NF-κB signaling pathway.

Multiplexing information flow through dynamic signalling systems

We consider how a signalling system can act as an information hub by multiplexing information arising from multiple signals. We formally define multiplexing, mathematically characterise which systems can multiplex and how well they can do it. While the results of this paper are theoretical, to motivate the idea of multiplexing, we provide experimental evidence that tentatively suggests that the NF-κB transcription factor can multiplex information about changes in multiple signals. We believe that our theoretical results may resolve the apparent paradox of how a system like NF-κB that regulates cell fate and inflammatory signalling in response to diverse stimuli can appear to have the low information carrying capacity suggested by recent studies on scalar signals. In carrying out our study, we introduce new methods for the analysis of large, nonlinear stochastic dynamic models, and develop computational algorithms that facilitate the calculation of fundamental constructs of information theory such as Kullback–Leibler divergences and sensitivity matrices, and link these methods to a new theory about multiplexing information. We show that many current models such as those of the NF-κB system cannot multiplex effectively and provide models that overcome this limitation using post-transcriptional modifications.

Cells use signalling systems to pass on information arising from their ever-changing environment to their processing units. These biochemical networks regulate the transmission of multiple signals within the noisy and complex cellular environment, controlling whether to turn on or off processes of cell defence, death, division, and others. The question of how they actually achieve that becomes particularly critical given that many diseases occur when signalling systems malfunction. In this paper, we develop methodology and computational tools for simulating, measuring and analysing the ability of signalling systems to transmit multi-dimensional signals. We specifically focus on the capacity of signalling systems to simultaneously transmit multiple signals, such as temperature changes, presence and concentration of cytokines, viral and bacterial pathogens or drugs, through a single noisy, dynamic signalling system. We argue that a signalling system can act as an information hub, sending information in a multiplexed fashion rather similar to the way in which telecommunications networks send multiple signals over a shared medium by combining them into one.

Nitidine chloride inhibits the appearance of cancer stem-like properties and regulates potential the mitochondrial membrane alterations of colon cancer cells

Background

Nitidine chloride (NC) is a natural alkaloid that can inhibit tumor growth and induce apoptosis in varieties of cancers. However, the effec12/268t of NC on colon cancer (CC) cells has not been extensively studied.

Methods

Conlon cancer SW480 cells was treated with different concentrations of NC (0.25, 0.5, 1, 2.5, 5, 10, 25, 50, 100, and 200 µM) in DMEM medium for 24 hours. Western blotting (WB) was used to detect the expression of related proteins, such as Ki67, PCNA, NANOG, SOX2, OCT4, Bcl-2, Bax, Caspase-3, Caspase-9, ERK1/2, p-ERK1/2, AKT, p-AKT, STAT3, p-STAT3, P65 and p-P65. The pellet formation experiment was used to detect the pellet formation of stem cells. The JC-1 experiment was used to detect the change of mitochondrial membrane potential. Kit was performed to detect the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA). In vivo experiments were used to verify the results of in vitro experiments. TUNEL assay was designed to detect the apoptosis in mice tissue. IHC was used to detect expression of Ki67 and OCT4 protein in tissue.

Results

NC significantly inhibited the expression levels of Ki-67 and a proliferating cell nuclear antigen (PCNA). NC can reduce the pellet colony and pellet size of tumor stem cells and block the stem cell characteristics of CC cells. The corresponding stem cell marker molecules NANOG, SOX2, and OCT4 were also downregulated. NC treatment induced the mitochondrial membrane potential depolarization of CC cells. The expression of pro-apoptotic proteins such as caspase-3, caspase-9, and Bax were upregulated, while the expression level of apoptotic Bcl-2 was significantly down-regulated. Moreover, NC reduced SOD activity and MDA content in CC cells. In addition, studies on pathway phosphorylation have shown that NC inhibits the expression of p-erk and p-akt proteins. Finally, the results were further confirmed by experiments in nude mice. NC inhibited tumor growth in mice. NC promoted apoptosis in tissues. NC inhibited the expression of Ki67 and OCT4 in tissues. NC inhibited the phosphorylation of pathway proteins ERK1/2 and AKT in tissues.

Conclusions

NC treatment inhibited the proliferation and stemness of CC tissues, promoted the apoptosis of tumor tissues, downregulated the expression of p-ERK and p-AKT in tumor tissues, which suggests that NC may play an important role in regulating ERK and AKT pathways.

Exportin 1 Inhibition Induces Nerve Growth Factor Receptor Expression to Inhibit the NF-κB Pathway in Preclinical Models of Pediatric High-Grade Glioma

High-grade glioma (HGG) is the leading cause of cancer-related death among children. Selinexor, an orally bioavailable, reversible inhibitor of the nuclear export protein, exportin 1, is in clinical trials for a range of cancers, including HGG. It inhibits the NF-κB pathway and strongly induces the expression of nerve growth factor receptor (NGFR) in preclinical cancer models. We hypothesized that selinexor inhibits NF-κB via upregulation of NGFR. In HGG cells, sensitivity to selinexor correlated with increased induction of cell surface NGFR expression. Knocking down NGFR in HGG cells increased proliferation, anchorage-independent growth, stemness markers, and levels of transcriptionally available nuclear NF-κB not bound to IκB-α, while decreasing apoptosis and sensitivity to selinexor. Increasing IκB-α levels in NGFR knockdown cells restored sensitivity to selinexor. Overexpression of NGFR using cDNA reduced levels of free nuclear NF-κB, decreased stemness markers, and increased markers of cellular differentiation. In all HGG lines tested, selinexor decreased phosphorylation of NF-κB at serine 536 (a site associated with increased transcription of proliferative and inflammatory genes). Because resistance to selinexor monotherapy occurred in our in vivo model, we screened selinexor with a panel of FDA-approved anticancer agents. Bortezomib, a proteasome inhibitor that inhibits the NF-κB pathway through a different mechanism than selinexor, showed synergy with selinexor against HGG in vitro Our results help elucidate selinexor's mechanism of action and identify NGFR as a potential biomarker of its effect in HGG and in addition suggest a combination therapy strategy for these challenging tumors.

Clusterin Silencing in Prostate Cancer Induces Matrix Metalloproteinases by an NF-κB-Dependent Mechanism

Clusterin (CLU) is a stress-activated glycoprotein, whose expression is altered both in inflammation and cancer. Previously, we showed that abrogation of CLU expression in cancer-prone mice (TRAMP) results in the enhancement of tumor spreading and homing, concomitant with an enhanced expression of NF-κB. In the present paper, we carried out an extensive experimental work by utilizing microarray gene expression data, as well as in vitro and in vivo models of prostate cancer (PCa). Our results demonstrated that (i) CLU expression is significantly downregulated in human PCa and inversely correlates with the expression of p65 in metastases; (ii) CLU overexpression in PCa cells reduces the Ser₅₃₆ phosphorylation of p65, inhibits NF-κB nuclear translocation, and reduces the transcription of matrix metalloproteinase-9 and metalloproteinase-2 (MMP-9 and MMP-2). Conversely, CLU silencing promotes NF-κB activation and transcriptional upregulation of MMP-9; and (iii) expression and activity of MMP-2 and MMP-9 are increased in CLU^−/− mice (CLUKO) and in TRAMP/CLUKO mice in comparison to their relative Clu^+/+ littermates. Taken together, our data support the hypothesis that CLU downregulation, an early and relevant event in PCa onset, may inhibit NF-κB activation and limit the execution of a transcriptional program that favor the disease progression towards a metastatic stage.

Cardamonin attenuates chronic inflammation and tumorigenesis in colon

Cardamonin (CAD) is a member of the aromatic ketones family that is closely related to anti-bacterial, anti-inflammatory and anti-cancer effects. Nevertheless, the physiological function of cardamonin in chronic colitis and colon cancer has not been well verified. We found that cardamonin treatment alleviates intestinal disease, including recurring colitis and colitis-associated tumorigenesis, along with the reduced secretion of IL-1β and TNF-α. Further, cardamonin inhibits cell viability and inflammation factors of colorectal cancer cells in vitro. In tumor cells, the inhibitory effect of cardamonin on cell proliferation is closely related to decreased phosphorylation of signal transducers and activators of transcription (STAT) signals. This study reveals the crucial role of cardamonin in sustaining gastrointestinal homeostasis and offers a new strategy for colon cancer therapy.

Targeting NF-κB signaling pathway in cancer by dietary polyphenols

Being a transcription factor, NF-κB regulates gene expressions involving cell survival and proliferation, drug resistance, metastasis, and angiogenesis. The activation of NF-κB plays a central role in the development of inflammation and cancer. Thus, the down-regulation of NF-κB may be an exciting target in prevention and treatment of cancer. NF-κB could act as a tumor activator or tumor suppressant decided by the site of action (organ). Polyphenols are widely distributed in plant species, consumption of which have been documented to negatively regulate the NF-κB signaling pathway. They depress the phosphorylation of kinases, inhibit NF-κB translocate into the nucleus as well as interfere interactions between NF-κB and DNA. Through inhibition of NF-κB, polyphenols downregulate inflammatory cascade, induce apoptosis and decrease cell proliferation and metastasis. This review highlights the anticancer effects of polyphenols on the basis of NF-κB signaling pathway regulation.

The interaction of YBX1 with G3BP1 promotes renal cell carcinoma cell metastasis via YBX1/G3BP1-SPP1- NF-κB signaling axis

Background

Renal cell carcinoma (RCC) is a deadly urological tumor that remains largely incurable. Our limited understanding of key molecular mechanisms underlying RCC invasion and metastasis has hampered efforts to identify molecular drivers with therapeutic potential. With evidence from our previous study revealing that nuclear overexpression of YBX1 is associated with RCC T stage and metastasis, we investigated the effects of YBX1 in RCC migration, invasion, and adhesion, and then characterized its interaction with RCC-associated proteins G3BP1 and SPP1.

Methods

Renal cancer cell lines, human embryonic kidney cells, and clinical samples were analyzed to investigate the functional role of YBX1 in RCC metastasis. YBX1 knockdown cells were established via lentiviral infection and subjected to adhesion, transwell migration, and invasion assay. Microarray, immunoprecipitation, dual-luciferase reporter assay, and classical biochemical assays were applied to characterize the mechanism of YBX1 interaction with RCC-associated proteins G3BP1 and SPP1.

Results

Knockdown of YBX1 in RCC cells dramatically inhibited cell adhesion, migration, and invasion. Mechanistic investigations revealed that YBX1 interaction with G3BP1 upregulated their downstream target SPP1 in vitro and in vivo, which led to an activated NF-κB signaling pathway. Meanwhile, knockdown of SPP1 rescued the YBX1/G3BP1-mediated activation of NF-κB signaling pathway, and RCC cell migration and invasion. We further showed that YBX1 expression was positively correlated with G3BP1 and SPP1 expression levels in clinical RCC samples.

Conclusions

YBX1 interacts with G3BP1 to promote metastasis of RCC by activating the YBX1/G3BP1–SPP1–NF-κB signaling axis.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1347-0) contains supplementary material, which is available to authorized users.

Absence of GdX/UBL4A Protects against Inflammatory Diseases by Regulating NF-кB Signaling in Macrophages and Dendritic Cells

Nuclear factor-kappa B (NF-κB) activation is critical for innate immune responses. However, cellular-intrinsic regulation of NF-κB activity during inflammatory diseases remains incompletely understood. Ubiquitin-like protein 4A (UBL4A, GdX) is a small adaptor protein involved in protein folding, biogenesis and transcription. Yet, whether GdX has a role during innate immune response is largely unknown. Methods: To investigate the involvement of GdX in innate immunity, we challenged GdX-deficient mice with lipopolysaccharides (LPS). To investigate the underlying mechanism, we performed RNA sequencing, real-time PCR, ELISA, luciferase reporter assay, immunoprecipitation and immunoblot analyses, flow cytometry, and structure analyses. To investigate whether GdX functions in inflammatory bowel disease, we generated dendritic cell (DC), macrophage (Mφ), epithelial-cell specific GdX-deficient mice and induced colitis with dextran sulfate sodium. Results: GdX enhances DC and Mφ-mediated innate immune defenses by positively regulating NF-κB signaling. GdX-deficient mice were resistant to LPS-induced endotoxin shock and DSS-induced colitis. DC- or Mφ- specific GdX-deficient mice displayed alleviated mucosal inflammation. The production of pro-inflammatory cytokines by GdX-deficient DCs and Mφ was reduced. Mechanistically, we found that tyrosine-protein phosphatase non-receptor type 2 (PTPN2, TC45) and protein phosphatase 2A (PP2A) form a complex with RelA (p65) to mediate its dephosphorylation whereas GdX interrupts the TC45/PP2A/p65 complex formation and restrict p65 dephosphorylation by trapping TC45. Conclusion: Our study provides a mechanism by which NF-κB signaling is positively regulated by an adaptor protein GdX in DC or Mφ to maintain the innate immune response. Targeting GdX could be a strategy to reduce over-activated immune response in inflammatory diseases.

STC1 promotes cell apoptosis via NF-κB phospho-P65 Ser536 in cervical cancer cells

Stanniocalin-1 (STC1) is a secreted glycoprotein hormone and involved in various types of human malignancies. Our previous studies revealed that STC1 inhibited cell proliferation and invasion of cervical cancer cells through NF-κB P65 activation, but the mechanism is poorly understood. In our studies, we found overexpression of STC1 promoted cell apoptosis while silencing of STC1 promoted cell growth of cervical cancer. Phospho-protein profiling and Western blotting results showed the expression of NF-κB related phosphorylation sites including NF-κB P65 (Ser536), IκBα, IKKβ, PI3K, and AKT was altered in STC1-overexpressed cervical cancer cells. Moreover, PI3K inhibitor LY294002, AKT-shRNA and IκBα-shRNA could decrease the protein content of phospho-P65 (Ser536), phospho-IκBα, phospho-AKT and phospho-IKKβ while increasing the level of P65 compared to STC1 overexpression groups in cervical cancer cells. Also, PI3K inhibitor LY294002, AKT-shRNA and IκBα-shRNA elevated the percentage of apoptosis and suppressed the G1/S transition in those cells. Additionally, STC1 level was decreased in cervical cancer, especial in stage II and III. The results of immunohistochemistry for the cervical cancer microarray showed that a lower level of STC1, phospho-PI3K and P65 protein expression in tumor tissues than that in normal tissues, and a higher level of phospho-P65 protein expression in tumor tissues, which is consistent with the results of the Western blotting. These data demonstrated that STC1 can promote cell apoptosis via NF-κB phospho-P65 (Ser536) by PI3K/AKT, IκBα and IKK signaling in cervical cancer cells. Our results offer the first mechanism that explains the link between STC1 and cell apoptosis in cervical cancer.

Lymphotoxin α fine-tunes T cell clonal deletion by regulating thymic entry of antigen-presenting cells

Medullary thymic epithelial cells (mTEC) purge the T cell repertoire of autoreactive thymocytes. Although dendritic cells (DC) reinforce this process by transporting innocuous peripheral self-antigens, the mechanisms that control their thymic entry remain unclear. Here we show that mTEC-CD4+ thymocyte crosstalk regulates the thymus homing of SHPS-1+ conventional DCs (cDC), plasmacytoid DCs (pDC) and macrophages. This homing process is controlled by lymphotoxin α (LTα), which negatively regulates CCL2, CCL8 and CCL12 chemokines in mTECs. Consequently, Ltα-deficient mice have increased expression of these chemokines that correlates with augmented classical NF-κB subunits and increased thymic recruitment of cDCs, pDCs and macrophages. This enhanced migration depends mainly on the chemokine receptor CCR2, and increases thymic clonal deletion. Altogether, this study identifies a fine-tuning mechanism of T cell repertoire selection and paves the way for therapeutic interventions to treat autoimmune disorders.

Fibroblast growth factor receptor signaling plays a key role in transformation induced by the TMPRSS2/ERG fusion gene and decreased PTEN

Prostate cancer is the most common visceral malignancy and the second leading cause of cancer deaths in US men. Correlative studies in human prostate cancers reveal a frequent association of the TMPRSS2/ERG (TE) fusion gene with loss of PTEN and studies in mouse models reveal that ERG expression and PTEN loss synergistically promote prostate cancer progression. To determine the mechanism by which ERG overexpression and PTEN loss leads to transformation, we overexpressed the TE fusion gene and knocked down PTEN in an immortalized but non-transformed prostate epithelial cell line. We show that ERG overexpression in combination with PTEN loss can transform these immortalized but non-tumorigenic cells, while either alteration alone was not sufficient to fully transform these cells. Expression microarray analysis revealed extensive changes in gene expression in cells expressing the TE fusion with loss of PTEN. Among these gene expression changes was increased expression of multiple FGF ligands and receptors. We show that activation of fibroblast growth factor receptor signaling plays a key role in transformation induced by TE fusion gene expression in association with PTEN loss. In addition, in vitro and in silico analysis reveals PTEN loss is associated with widespread increases in FGF ligands and receptors in prostate cancer. Inhibitors of FGF receptor signaling are currently entering the clinic and our results suggests that FGF receptor signaling is a therapeutic target in cancers with TE fusion gene expression and PTEN loss.

Induction of cancer cell stemness by depletion of macrohistone H2A1 in hepatocellular carcinoma

Hepatocellular carcinomas (HCC) contain a subpopulation of cancer stem cells (CSCs), which exhibit stem cell-like features and are responsible for tumor relapse, metastasis, and chemoresistance. The development of effective treatments for HCC will depend on a molecular-level understanding of the specific pathways driving CSC emergence and stemness. MacroH2A1 is a variant of the histone H2A and an epigenetic regulator of stem-cell function, where it promotes differentiation and, conversely, acts as a barrier to somatic-cell reprogramming. Here, we focused on the role played by the histone variant macroH2A1 as a potential epigenetic factor promoting CSC differentiation. In human HCC sections we uncovered a significant correlation between low frequencies of macroH2A1 staining and advanced, aggressive HCC subtypes with poorly differentiated tumor phenotypes. Using HCC cell lines, we found that short hairpin RNA-mediated macroH2A1 knockdown induces acquisition of CSC-like features, including the growth of significantly larger and less differentiated tumors when injected into nude mice. MacroH2A1-depleted HCC cells also exhibited reduced proliferation, resistance to chemotherapeutic agents, and stem-like metabolic changes consistent with enhanced hypoxic responses and increased glycolysis. The loss of macroH2A1 increased expression of a panel of stemness-associated genes and drove hyperactivation of the nuclear factor kappa B p65 pathway. Blocking phosphorylation of nuclear factor kappa B p65 on Ser536 inhibited the emergence of CSC-like features in HCC cells knocked down for macroH2A1. Conclusion: The absence of histone variant macroH2A1 confers a CSC-like phenotype to HCC cells in vitro and in vivo that depends on Ser536 phosphorylation of nuclear factor kappa B p65; this pathway may hold valuable targets for the development of CSC-focused treatments for HCC. (Hepatology 2018;67:636-650).

Recombinant Mtb9.8 of Mycobacterium bovis stimulates TNF-α and IL-1β secretion by RAW264.7 macrophages through activation of NF-κB pathway via TLR2

The Mtb9.8 antigenic protein of Mycobacterium bovis/Mycobacterium tuberculosis has been identified as a target of the T-cell response. However, the interaction of Mtb9.8 with Toll-like receptors (TLRs) and the relevant signaling pathways have not been fully clarified. In this study, recombinant Mtb9.8 (rMtb9.8) derived from M. bovis-stimulated RAW264.7 cells initiated the secretion of TNF-α and IL-1β in a dose-dependent manner. Blocking assays show that TLR2-neutralizing antibody decreases the production of TNF-α and IL-1β. Moreover, NF-κB activation is associated with TNF-α and IL-1β production by rMtb9.8 stimulation, and rMtb9.8 stimulation also induces the phosphorylation of NF-κB p65 at Ser536 and its rapid nuclear translocation in RAW264.7 cells. Furthermore, NF-κB luciferase activity is rapidly activated in response to rMtb9.8 in RAW264.7 cells and is also significantly increased in rMtb9.8-induced HEK293-TLR2. However, these activations were abrogated in cells with a dominant-negative mutation of NF-κB p65 and by treatment with anti-TLR2 antibody. We also find that rMtb9.8 induces the activation of IRF-1. These findings indicate that M. bovis-derived rMtb9.8 activates the NF-κB pathway via TLR2 in RAW264.7 cells. In particular, it phosphorylates NF-κB p65 at Ser536 and induces nuclear translocation, thereby leading to the production of TNF-α and IL-1β, which correlates with the induction of IRF-1.

HSP90 inhibitor (NVP-AUY922) enhances the anti-cancer effect of BCL-2 inhibitor (ABT-737) in small cell lung cancer expressing BCL-2

Small cell lung cancer (SCLC) cannot be efficiently controlled using existing chemotherapy and radiotherapy approaches, indicating the need for new therapeutic strategies. Although ABT-737, a B-cell lymphoma-2 (BCL-2) inhibitor, exerts anticancer effects against BCL-2-expressing SCLC, monotherapy with ABT-737 is associated with limited clinical activity because of the development of resistance and toxicity. Here, we examined whether combination therapy with ABT-737 and heat shock protein 90 (HSP90) inhibitor NVP-AUY922 exerted synergistic anticancer effects on SCLC. We found that the combination of ABT-737 and NVP-AUY922 synergistically induced the apoptosis of BCL-2-expressing SCLC cells. NVP-AUY922 downregulated the expression of AKT and ERK, which activate MCL-1 to induce resistance against ABT-737. The synergistic effect was also partly due to blocking NF-κB activation, which induces anti-apoptosis protein expressions. However, interestingly, targeting BCL-2 and MCL-1 or BCL2 and NF-κB did not induce the cytotoxicity. In conclusion, our study showed that combination of BCL2 inhibitor with HSP90 inhibitor increased activity in in vitro and in vivo study in only BCL-2 expressing SCLC compared to either single BCL2 inhibitor or HSP inhibitor. The enhanced activity might be led by blocking several apoptotic pathways simultaneously rather than a specific pathway.

Cancer/testis antigen SPATA19 is frequently expressed in benign prostatic hyperplasia and prostate cancer

Spermatogenesis-associated 19 (SPATA19) is a cancer/testis antigen overexpressed in various cancers. However, its protein expression profile in malignant or non-malignant tissues remains unknown. Thus, in this study, we investigated SPATA19 protein expression patterns in a panel of non-malignant human samples and primary prostate cancer (PCa) with or without benign prostatic hyperplasia (BPH) tissues. SPATA19 was absent in all non-malignant tissues investigated (n=14) except testis and prostate tissues. In terms of malignancies, all PCa cases were positive for SPATA19 exhibiting frequency between 20 and 100% (median 85%) with 63 (52.5%) and 57 (47.5%) cases demonstrating weak/moderate and strong intensities, respectively. Thirty-nine PCa cases (32.5%) contained BPH, and all BPH glands were SPATA19 positive (frequency between 20 and 100%; median 90%) with 13 (33.3%) demonstrating strong SPATA19 expression. Higher SPATA19 expression (higher frequency, intensity, or H-score) was not associated with overall survival or disease-specific survival (DFS) in all PCa cases. However, biochemical recurrence (BR) was associated with worse DFS (p = 0.005) in this cohort of 120 patients, and cases with strong SPATA19 intensity were associated with BR (p = 0.020). In conclusion, we showed that SPATA19 protein was frequently expressed in both BPH and PCa glands, and this warrants future investigations on its pathogenic roles in the disease.

SERP1 is a novel marker of poor prognosis in pancreatic ductal adenocarcinoma patients via anti-apoptosis and regulating SRPRB/NF-κB axis

Stress associated endoplasmic reticulum protein 1 (SERP1), can cause accumulation of unfolded proteins in ER stress. However, studies on the role of SERP1 in pancreatic ductal adenocarcinoma (PDAC) are still incomplete. The present study aimed at identifying whether SERP1 acts as a potential novel prognostic marker of PDAC, and analyzed its possible mechanism. GEO database analysis showed SERP1 was significantly upregulated in PDAC tissues, and strongly associated with advanced clinical stage of PDAC patients from TCGA database. Univariate and multivariate Cox regression analysis further revealed SERP1 high expression was an independent factor for the prognosis of PDAC. Gene set enrichment analysis (GSEA) revealed that SERP1 was mainly involved in regulating cell apoptosis and nuclear factor-κB (NF-κB) signaling pathway, and downregulated SERP1 significantly promoted PANC-1 cell apoptosis. To further explore its possible mechanism, protein-protein interaction (PPI) and gene ontology (GO) analysis showed the functions of proteins interacting with SERP1 were mainly enriched in regulating cell apoptosis, and SRP receptor β subunit (SRPRB) was the core of the whole PPI network. The expression of SERP1 was negatively correlated with SRPRB expression. In vitro, downregulated SERP1 significantly increased SRPRB expression. Furthermore, upregulated SRPRB could increase cell apoptosis rate and decreased the expression level of NF-κB and the phosphorylation NF-κB. The above results indicated that SERP1 as a potential novel prognostic marker of PDAC probably via regulating cell apoptosis and NF-κB activation, which may be associated with SRPRB.

Toll-like receptor 4 promotes proliferation and apoptosis resistance in human papillomavirus-related cervical cancer cells through the Toll-like receptor 4/nuclear factor-κB pathway

Toll-like receptor 4 is overexpressed in various tumors, including cervical carcinoma. However, the role of Toll-like receptor 4 in cervical cancer remains controversial, and the underlying mechanisms are largely elusive. Therefore, Toll-like receptor 4 in cervical cancer and related mechanisms were investigated in this study. Quantitative reverse transcription polymerase chain reaction and western blot analyses were used to detect messenger RNA and protein levels in HeLa, Caski, and C33A cells with different treatments. Proliferation was quantified using Cell Counting Kit-8. Cell cycle distribution and apoptosis were assessed by flow cytometry. Higher levels of Toll-like receptor 4 expression were found in human papillomavirus-positive cells compared to human papillomavirus-negative cells. Proliferation of HeLa and Caski cells was promoted in lipopolysaccharide-stimulated groups but suppressed in short hairpin RNA-transfected groups. Apoptosis rates were lower in lipopolysaccharide-stimulated groups relative to short hairpin RNA-transfected groups. In addition, G2-phase distribution was enhanced when Toll-like receptor 4 was downregulated. Moreover, the pNF-κBp65 level was positively correlated with the Toll-like receptor 4 level in HeLa and Caski cells, though when an nuclear factor-κB inhibitor was applied to lipopolysaccharide-stimulated groups, the patterns of proliferation and apoptosis were opposite to those of the lipopolysaccharide-stimulated groups without inhibitor treatment. In conclusion, these data suggest that Toll-like receptor 4 promotes proliferation and apoptosis resistance in human papillomavirus-related cervical cancer cells at least in part through the Toll-like receptor 4/nuclear factor-κB pathway, which may be correlated with the occurrence and development of cervical carcinoma.

p62/SQSTM1 as an oncotarget mediates cisplatin resistance through activating RIP1-NF-κB pathway in human ovarian cancer cells

Platinum‐based therapeutic strategies have been widely used in ovarian cancer treatment. However, drug resistance has greatly limited therapeutic efficacy. Recently, tolerance to cisplatin has been attributed to other factors unrelated to DNA. p62 (also known as SQSTM1) functions as a multifunctional hub participating in tumorigenesis and may be a therapeutic target. Our previous study showed that p62 was overexpressed in drug‐resistant ovarian epithelial carcinoma and its inhibition increased the sensitivity to cisplatin. In this study, we demonstrate that the activity of the NF‐κB signaling pathway and K63‐linked ubiquitination of RIP1 was higher in cisplatin‐resistant ovarian (SKOV3/DDP) cells compared with parental cells. In addition, cisplatin resistance could be reversed by inhibiting the expression of p62 using siRNA. Furthermore, deletion of the ZZ domain of p62 that interacts with RIP1 in SKOV3 cells markedly decreased K63‐linked ubiquitination of RIP1 and inhibited the activation of the NF‐κB signaling pathway. Moreover, loss of the ZZ domain from p62 led to poor proliferative capacity and high levels of apoptosis in SKOV3 cells and made them more sensitive to cisplatin treatment. Collectively, we provide evidence that p62 is implicated in the activation of NF‐κB signaling that is partly dependent on RIP1. p62 promotes cell proliferation and inhibits apoptosis thus mediating drug resistance in ovarian cancer cells.

RGS12 Is a Novel Tumor-Suppressor Gene in African American Prostate Cancer That Represses AKT and MNX1 Expression

African American (AA) men exhibit a relatively high incidence and mortality due to prostate cancer even after adjustment for socioeconomic factors, but the biological basis for this disparity is unclear. Here, we identify a novel region on chromosome 4p16.3 that is lost selectively in AA prostate cancer. The negative regulator of G-protein signaling RGS12 was defined as the target of 4p16.3 deletions, although it has not been implicated previously as a tumor-suppressor gene. RGS12 transcript levels were relatively reduced in AA prostate cancer, and prostate cancer cell lines showed decreased RGS12 expression relative to benign prostate epithelial cells. Notably, RGS12 exhibited potent tumor-suppressor activity in prostate cancer and prostate epithelial cell lines in vitro and in vivo We found that RGS12 expression correlated negatively with the oncogene MNX1 and regulated its expression in vitro and in vivo Further, MNX1 was regulated by AKT activity, and RGS12 expression decreased total and activated AKT levels. Our findings identify RGS12 as a candidate tumor-suppressor gene in AA prostate cancer, which acts by decreasing expression of AKT and MNX1, establishing a novel oncogenic axis in this disparate disease setting. Cancer Res; 77(16); 4247-57. ©2017 AACR.

Targeting NF-kappa B Signaling by Artesunate Restores Sensitivity of Castrate-Resistant Prostate Cancer Cells to Antiandrogens

Androgen deprivation therapy (ADT) is the most preferred treatment for men with metastatic prostate cancer (PCa). However, the disease eventually progresses and develops resistance to ADT in majority of the patients, leading to the emergence of metastatic castration-resistant prostate cancer (mCRPC). Here, we assessed artesunate (AS), an artemisinin derivative, for its anticancer properties and ability to alleviate resistance to androgen receptor (AR) antagonists. We have shown AS in combination with bicalutamide (Bic) attenuates the oncogenic properties of the castrate-resistant (PC3, 22RV1) and androgen-responsive (LNCaP) PCa cells. Mechanistically, AS and Bic combination inhibits nuclear factor (NF)-κB signaling and decreases AR and/or AR-variant 7 expression via ubiquitin-mediated proteasomal degradation. The combination induces oxidative stress and apoptosis via survivin downregulation and caspase-3 activation, resulting in poly-ADP-ribose polymerase (PARP) cleavage. Moreover, preclinical castrate-resistant PC3 xenograft studies in NOD/SCID mice (n =28, seven per group) show remarkable tumor regression and significant reduction in lungs and bone metastases upon administering AS (50 mg/kg per day in two divided doses) and Bic (50 mg/kg per day) via oral gavage. Taken together, we for the first time provide a compelling preclinical rationale that AS could disrupt AR antagonist-mediated resistance observed in mCRPC. The current study also indicates that the therapeutic combination of Food and Drug Administration-approved AS or NF-κB inhibitors and AR antagonists may enhance the clinical efficacy in the treatment of mCRPC patients.

Extracellular Hsp70 Enhances Mesoangioblast Migration via an Autocrine Signaling Pathway

Mouse mesoangioblasts are vessel-associated progenitor stem cells endowed with the ability of multipotent mesoderm differentiation. Therefore, they represent a promising tool in the regeneration of injured tissues. Several studies have demonstrated that homing of mesoangioblasts into blood and injured tissues are mainly controlled by cytokines/chemokines and other inflammatory factors. However, little is known about the molecular mechanisms regulating their ability to traverse the extracellular matrix (ECM). Here, we demonstrate that membrane vesicles released by mesoangioblasts contain Hsp70, and that the released Hsp70 is able to interact by an autocrine mechanism with Toll-like receptor 4 (TLR4) and CD91 to stimulate migration. We further demonstrate that Hsp70 has a positive role in regulating matrix metalloproteinase 2 (MMP2) and MMP9 expression and that MMP2 has a more pronounced effect on cell migration, as compared to MMP9. In addition, the analysis of the intracellular pathways implicated in Hsp70 regulated signal transduction showed the involvement of both PI3K/AKT and NF-κB. Taken together, our findings present a paradigm shift in our understanding of the molecular mechanisms that regulate mesoangioblast stem cells ability to traverse the extracellular matrix (ECM). J. Cell. Physiol. 232: 1845-1861, 2017. © 2016 Wiley Periodicals, Inc.

Aberrant control of NF-κB in cancer permits transcriptional and phenotypic plasticity, to curtail dependence on host tissue: molecular mode

The role of the transcription factor NF-κB in shaping the cancer microenvironment is becoming increasingly clear. Inflammation alters the activity of enzymes that modulate NF-κB function, and causes extensive changes in genomic chromatin that ultimately drastically alter cell-specific gene expression. NF-κB regulates the expression of cytokines and adhesion factors that control interactions among adjacent cells. As such, NF-κB fine tunes tissue cellular composition, as well as tissues' interactions with the immune system. Therefore, NF-κB changes the cell response to hormones and to contact with neighboring cells. Activating NF-κB confers transcriptional and phenotypic plasticity to a cell and thereby enables profound local changes in tissue function and composition. Research suggests that the regulation of NF-κB target genes is specifically altered in cancer. Such alterations occur not only due to mutations of NF-κB regulatory proteins, but also because of changes in the activity of specific proteostatic modules and metabolic pathways. This article describes the molecular mode of NF-κB regulation with a few characteristic examples of target genes.

Effects of mutations in Wnt/β-catenin, hedgehog, Notch and PI3K pathways on GSK-3 activity-Diverse effects on cell growth, metabolism and cancer

Glycogen synthase kinase-3 (GSK-3) is a serine/threonine kinase that participates in an array of critical cellular processes. GSK-3 was first characterized as an enzyme that phosphorylated and inactivated glycogen synthase. However, subsequent studies have revealed that this moon-lighting protein is involved in numerous signaling pathways that regulate not only metabolism but also have roles in: apoptosis, cell cycle progression, cell renewal, differentiation, embryogenesis, migration, regulation of gene transcription, stem cell biology and survival. In this review, we will discuss the roles that GSK-3 plays in various diseases as well as how this pivotal kinase interacts with multiple signaling pathways such as: PI3K/PTEN/Akt/mTOR, Ras/Raf/MEK/ERK, Wnt/beta-catenin, hedgehog, Notch and TP53. Mutations that occur in these and other pathways can alter the effects that natural GSK-3 activity has on regulating these signaling circuits that can lead to cancer as well as other diseases. The novel roles that microRNAs play in regulation of the effects of GSK-3 will also be evaluated. Targeting GSK-3 and these other pathways may improve therapy and overcome therapeutic resistance.

MNX1 Is Oncogenically Upregulated in African-American Prostate Cancer

Incidence and mortality rates for prostate cancer are higher in African-American (AA) men than in European-American (EA) men, but the biologic basis for this disparity is unclear. We carried out a detailed analysis of gene expression changes in prostate cancer compared with their matched benign tissues in a cohort of AA men and compared them with existing data from EA men. In this manner, we identified MNX1 as a novel oncogene upregulated to a relatively greater degree in prostate cancer from AA men. Androgen and AKT signaling play a central role in the pathogenesis of prostate cancer and we found that both of these signaling pathways increased MNX1 expression. MNX1 in turn upregulated lipid synthesis by stimulating expression of SREBP1 and fatty acid synthetase. Our results define MNX1 as a novel targetable oncogene increased in AA prostate cancer that is associated with aggressive disease. Cancer Res; 76(21); 6290-8. ©2016 AACR.

Recombinant human alpha fetoprotein synergistically potentiates the anti-cancer effects of 1'-S-1'-acetoxychavicol acetate when used as a complex against human tumours harbouring AFP-receptors

Purpose

Previous in vitro and in vivo studies have reported that 1′-S-1′-acetoxychavicol acetate (ACA) isolated from rhizomes of the Malaysian ethno-medicinal plant Alpinia conchigera Griff (Zingiberaceae) induces apoptosis-mediated cell death in tumour cells via dysregulation of the NF-κB pathway. However there were some clinical development drawbacks such as poor in vivo solubility, depreciation of biological activity upon exposure to an aqueous environment and non-specific targeting of tumour cells. In the present study, all the problems above were addressed using the novel drug complex formulation involving recombinant human alpha fetoprotein (rhAFP) and ACA.

Experimental Design

To study the synergistic effect of both agents on human cancer xenografts, athymic nude (Nu/Nu) mice were used and treated with various combination regimes intraperitoneally. Serum levels of tumour markers for carcinoembryonic antigen (CEA) and prostate specific antigen (PSA) were assessed using sandwich ELISA. IHC and Western blotting were also conducted on in vivo tumour biopsies to investigate the involvement of NF-κB regulated genes and inflammatory biomarkers. Quantification and correlation between drug efficacies and AFP-receptors were done using IF-IC and Pearson's correlation analysis.

Results

Mice exposed to combined treatments displayed higher reductions in tumour volume compared to stand alone agents, consistent with in vitro cytotoxicity assays. Milder signs of systemic toxicity, such as loss in body weight and inflammation of vital organs were also demonstrated compared to stand alone treatments. Tumour marker levels were consistent within all rhAFP/ACA treatment groups where levels of CEA and PSA were initially elevated upon commencement of treatment, and consecutively reduced corresponding to a decrease in tumour bulk volume. Both IHC and Western blotting results indicated that the combined action of rhAFP/ACA was not only able to down-regulate NF-κB activation, but also reduce the expression of NF-κB regulated genes and inflammatory biomarkers. The efficacy of rhAFP/ACA complex was also found to be weakly negatively correlated to the level of surface AFP-receptors between tumour types.

Conclusions

This drug complex formulation shows great therapeutic potential against AFP-receptor positive tumours, and serves as a basis to overcome insoluble and non-specific anti-neoplastic molecules.

Isoliensinine, a Bioactive Alkaloid Derived from Embryos of Nelumbo nucifera, Induces Hepatocellular Carcinoma Cell Apoptosis through Suppression of NF-κB Signaling

Isoliensinine (isolie) is an alkaloid produced by the edible plant Nelumbo nucifera. Here, we unveiled that isolie was able to provoke HepG2, Huh-7, and H22 hepatocellular carcinoma (HCC) cell apoptosis. Isolie decreased NF-κB activity and constitutive phosphorylation of NF-κB p65 subunit at Ser536 in HCC cells. Overexpression of p65 Ser536 phosphorylation mimics abrogated isolie-mediated HCC cell apoptosis. Furthermore, intraperitoneal injection of isolie inhibited the growth of Huh-7 xenografts in nude mice. Additionally, isolie given by both intraperitoneal injection and gavage diminished the proliferation of transplanted H22 cells in Kunming mice. Reduced tumor growth in vivo was associated with inhibited p65 phosphorylation at Ser536 and declined NF-κB activity in tumor tissues. Finally, we revealed that isolie was bioavailable in the blood of mice and exhibited no detectable toxic effects on tumor-bearing mice. Our data provided strong evidence for the anti-HCC effect of isolie.

Novel roles of androgen receptor, epidermal growth factor receptor, TP53, regulatory RNAs, NF-kappa-B, chromosomal translocations, neutrophil associated gelatinase, and matrix metalloproteinase-9 in prostate cancer and prostate cancer stem cells

Approximately one in six men will be diagnosed with some form of prostate cancer in their lifetime. Over 250,000 men worldwide die annually due to complications from prostate cancer. While advancements in prostate cancer screening and therapies have helped in lowering this statistic, better tests and more effective therapies are still needed. This review will summarize the novel roles of the androgen receptor (AR), epidermal growth factor receptor (EGFR), the EGFRvIII variant, TP53, long-non-coding RNAs (lncRNAs), microRNAs (miRs), NF-kappa-B, chromosomal translocations, neutrophil associated gelatinase, (NGAL), matrix metalloproteinase-9 (MMP-9), the tumor microenvironment and cancer stem cells (CSC) have on the diagnosis, development and treatment of prostate cancer.

IKK phosphorylation of NF-κB at serine 536 contributes to acquired cisplatin resistance in head and neck squamous cell cancer

Current treatment methods for advanced head and neck squamous cell carcinoma (HNSCC) include surgery, radiation therapy and chemotherapy. For recurrent and metastatic HNSCC, cisplatin is the most common treatment option, but most of patients will eventually develop cisplatin resistance. Therefore, it is imperative to define the mechanisms involved in cisplatin resistance and find novel therapeutic strategies to overcome this deadly disease. In order to determine the role of nuclear factor-kappa B (NF-κB) in contributing to acquired cisplatin resistance in HNSCC, the expression and activity of NF-κB and its upstream kinases, IKKα and IKKβ, were evaluated and compared in three pairs of cisplatin sensitive and resistant HNSCC cell lines, including a pair of patient derived HNSCC cell line. The experiments revealed that NF-κB p65 activity was elevated in cisplatin resistant HNSCC cells compared to that in their parent cells. Importantly, the phosphorylation of NF-κB p65 at serine 536 and the phosphorylation of IKKα and IKKβ at their activation loops were dramatically elevated in the resistant cell lines. Furthermore, knockdown of NF-κB or overexpression of p65-S536 alanine (p65-S536A) mutant sensitizes resistant cells to cisplatin. Additionally, the novel IKKβ inhibitor CmpdA has been shown to consistently block the phosphorylation of NF-κB at serine 536 while also dramatically improving the efficacy of cisplatin in inhibition of cell proliferation and induction of apoptosis in the cisplatin resistant cancer cells. These results indicated that IKK/NF-κB plays a pivotal role in controlling acquired cisplatin resistance and that targeting the IKK/NF-κB signaling pathway may provide a possible therapeutic method to overcome the acquired resistance to cisplatin in HNSCC.

Growth factors mediated cell signalling in prostate cancer progression: Implications in discovery of anti-prostate cancer agents

Cancer is one of the leading causes of mortality amongst world's population, in which prostate cancer is one of the most encountered malignancies among men. Globally, it is the sixth leading cause of cancer-related death in men. Prostate cancer is more prevalent in the developed world and is increasing at alarming rates in the developing countries. Prostate cancer is mostly a very sluggish progressing disease, caused by the overproduction of steroidal hormones like dihydrotestosterone or due to over-expression of enzymes such as 5-α-reductase. Various studies have revealed that growth factors play a crucial role in the progression of prostate cancer as they act either by directly elevating the level of steroidal hormones or upregulating enzyme efficacy by the active feedback mechanism. Presently, treatment options for prostate cancer include radiotherapy, surgery and chemotherapy. If treatment is done with prevailing traditional chemotherapy; it leads to resistance and development of androgen-independent prostate cancer that further complicates the situation with no cure option left. The current review article is an attempt to cover and establish an understanding of some major signalling pathways intervened through survival factors (IGF-1R), growth factors (TGF-α, EGF), Wnt, Hedgehog, interleukin, cytokinins and death factor receptor which are frequently dysregulated in prostate cancer. This will enable the researchers to design and develop better therapeutic strategies targeting growth factors and their cross talks mediated prostate cancer cell signalling.