NF-kappaB in cancer: a marked target

Versatile function of NF-ĸB in inflammation and cancer

Nuclear factor-kappaB (NF-ĸB) plays a crucial role in both innate and adaptive immune systems, significantly influencing various physiological processes such as cell proliferation, migration, differentiation, survival, and stemness. The function of NF-ĸB in cancer progression and response to chemotherapy has gained increasing attention. This review highlights the role of NF-ĸB in inflammation control, biological mechanisms, and therapeutic implications in cancer treatment. NF-ĸB is instrumental in altering the release of inflammatory factors such as TNF-α, IL-6, and IL-1β, which are key in the regulation of carcinogenesis. Specifically, in conditions including colitis, NF-ĸB upregulation can intensify inflammation, potentially leading to the development of colorectal cancer. Its pivotal role extends to regulating the tumor microenvironment, impacting components such as macrophages, fibroblasts, T cells, and natural killer cells. This regulation influences tumorigenesis and can dampen anti-tumor immune responses. Additionally, NF-ĸB modulates cell death mechanisms, notably by inhibiting apoptosis and ferroptosis. It also has a dual role in stimulating or suppressing autophagy in various cancers. Beyond these functions, NF-ĸB plays a role in controlling cancer stem cells, fostering angiogenesis, increasing metastatic potential through EMT induction, and reducing tumor cell sensitivity to chemotherapy and radiotherapy. Given its oncogenic capabilities, research has focused on natural products and small molecule compounds that can suppress NF-ĸB, offering promising avenues for cancer therapy.

In vitro study on anti-proliferative and anti-cancer activity of picrosides in triple-negative breast cancer

Picrorhiza kurroa, an "Indian gentian," a known Himalayan medicinal herb with rich source of phytochemicals like picrosides I, II, and other glycosides, has been traditionally used for the treatment of liver and respiratory ailments. Picrosides anti-proliferative, anti-oxidant, anti-inflammatory and other pharmacological properties were evaluated in treating triple-negative breast cancer (TNBC). Picroside I and II were procured from Sigma-Aldrich and were analyzed for anti-cancer activity in triple-negative breast cancer (MDA-MB-231) cells. Cell viability was analyzed using MTT and trypan blue assays. Apoptosis was analyzed through DNA fragmentation and Annexin V/PI flow cytometric analysis. Wound healing and cell survival assays were employed to determine the inhibition of invasion capacity and anti-proliferative activity of picrosides in MDA-MB-231 cells. Measurement of intracellular ROS was studied through mitochondrial membrane potential assessment using DiOC6 staining for anti-oxidant activity of picrosides in MDA-MB-231 cells. Both Picroside I and II have shown decreased cell viability of MDA-MB-231 cells with increasing concentrations. IC50 values of 95.3 µM and 130.8 µM have been obtained for Picroside I and II in MDA-MB-231 cells. Early apoptotic phase have shown an increase of 20% (p < 0.05) with increasing concentrations (0, 50, 75, and 100 µM) of Picroside I and 15% (p < 0.05) increase with Picroside II. Decrease in mitochondrial membrane potential of 2-2.5-fold (p < 0.05) was observed which indicated decreased reactive oxygen species (ROS) generation with increasing concentrations of Picroside I and II. An increasing percentage of 70-80% (p < 0.05) cell population was arrested in G0/G1 phase of cell cycle after Picroside I and II treatment in cancer cells. Our results suggest that Picroside I and II possess significant anti-proliferative and anti-cancer activity which is mediated by inhibition of cell growth, decreased mitochondrial membrane potential, DNA damage, apoptosis, and cell cycle arrest. Therefore, Picroside I and II can be developed as a potential anti-cancer drug of future and further mechanistic studies are underway to identify the mechanism of anti-cancer potential.

Cytotoxicity of dioncophylline A and related naphthylisoquinolines in leukemia cells, mediated by NF-κB inhibition, angiogenesis suppression, G2/M cell cycle arrest, and autophagy induction

BACKGROUND

Inhibition of NF-κB activity represents a strategy to treat acute myeloid leukemia, one of the most lethal leukemia types. Naphthylisoquinolines (NIQs) are cytotoxic alkaloids from lianas of the families Ancistrocladaceae and Dioncophyllaceae, which are indigenous to tropical rainforests.

PURPOSE

Uncovering therapeutic possibilities and underlying molecular mechanisms of dioncophylline A and its derivatives towards NF-κB related cellular processes.

METHODS

Resazurin-based cell viability assay was performed for dioncophylline A and three derivatives on wild-type CCRF-CEM and multidrug-resistant CEM/ADR5000 cells. Transcriptome analysis was executed to discover cellular functions and molecular networks associated with dioncophylline A treatment. Expression changes obtained by mRNA microarray hybridization were confirmed using qRT-PCR. Molecular docking was applied to predict the affinity of the NIQs with NF-κB. To validate the in silico approach, NF-κB reporter assays were conducted on HEK-Blue™ Null1 cells. Cell death mechanisms and cell cycle arrest were studied using flow cytometry. The potential activity on angiogenesis was evaluated with the endothelial cell tube formation assay on HUVECs using fluorescence microscopy. Intracellular NF-κB location in HEK-Blue™ Null1 cells was visualized with immunofluorescence. Finally, the anti-tumor activity of dioncophylline A was studied by a xenograft zebrafish model in vivo.

RESULTS

Our study demonstrated that dioncophylline A and its derivatives exerted potent cytotoxicity on leukemia cells. Using Ingenuity Pathway Analysis, we identified the NF-κB network as the top network, and docking experiments predicted dioncophylline A and two of its derivatives sharing the same binding pocket with the positive control compound, triptolide. Dioncophylline A showed the best inhibitory activity in NF-κB reporter assays compared to its derivatives, caused autophagy rather than apoptosis, and induced G2/M arrest. It also prevented NF-κB translocation from the cytoplasm to the nucleus. Tube formation as an angiogenesis marker was significantly suppressed by dioncophylline A treatment. Finally, the remarkable anti-tumor activity of dioncophylline A was proven in zebrafish in vivo.

CONCLUSION

Taken together, we report for the first time the molecular mechanism behind the cytotoxic effect of dioncophylline A on leukemia cells. Dioncophylline A showed strong cytotoxic activity, inhibited NF-κB translocation, significantly affected the NF-κB in silico and in vitro, subdued tube formation, induced autophagy, and exerted antitumor activity in vivo. Our findings enlighten both the cellular functions including the NF-κB signaling pathway and the cytotoxic mechanism affected by dioncophylline A.

Jozimine A2, a Dimeric Naphthylisoquinoline (NIQ) Alkaloid, Shows In Vitro Cytotoxic Effects against Leukemia Cells through NF-κB Inhibition

Naphthylisoquinoline (NIQ) alkaloids are rising as a promising class of secondary metabolites with pharmaceutical potential. NF-κB has already been recognized as a significant modulator of cancer proliferation and drug resistance. We have previously reported the mechanisms behind the cytotoxic effect of dioncophylline A, an NIQ monomer, in leukemia cells. In the current study, we have investigated the cytotoxic effect of jozimine A2, an NIQ dimer, on leukemia cells in comparison to a second, structurally unsymmetric dimer, michellamine B. To this end, molecular docking was applied to predict the binding affinity of the dimers towards NF-κB, which was then validated through microscale thermophoresis. Next, cytotoxicity assays were performed on CCRF-CEM cells and multidrug-resistant CEM/ADR5000 cells following treatment. Transcriptome analysis uncovered the molecular networks affected by jozimine A2 and identified the cell cycle as one of the major affected processes. Cell death modes were evaluated through flow cytometry, while angiogenesis was measured with the endothelial cell tube formation assay on human umbilical vein endothelial cells (HUVECs). The results indicated that jozimine A2 bound to NF-κB, inhibited its activity and prevented its translocation to the nucleus. In addition, jozimine A2 induced cell death through apoptosis and prevented angiogenesis. Our study describes the cytotoxic effect of jozimine A2 on leukemia cells and explains the interactions with the NF-κB signaling pathway and the anticancer activity.

Effects of Exhaustive Exercise on Inflammatory, Apoptotic, and Antioxidative Signaling Pathways in Human Peripheral Blood Mononuclear Cells

In the present study, we investigated the effects of exhaustive exercise and recovery on inflammatory, pro-apoptotic, and anti-oxidative responses in human peripheral blood mononuclear cells (PBMCs). Sixteen volunteers participated in a guided physical activity program in which they were subjected to progressive exercise on the treadmill until they were exhausted followed by an 1-hour recovery period. Isolated human PBMCs were collected before exercise, immediately after exercise, and after 1-hour recovery. Exhaustive exercise induced expression of heme oxygenase-1 and glutamate cysteine ligase catalytic subunit and activation of NF-κB and NF-E2 related factor 2 (Nrf2). Apoptosis, as measured by activity and cleavage of caspase-3 and its substrate PARP also significantly increased. However, induction of redox signaling and the pro-apoptotic response fully returned to the baseline level during the 1-hour recovery period. On the other hand, COX-2 expression was continuously elevated after exercise cessation throughout the 1-hour recovery period. Taking all these findings into account, we conclude that exhaustive exercise transiently induces Nrf2-mediated antioxidant gene expression and eliminates damaged cells through apoptosis as part of an adaptive cytoprotective response against oxidative and inflammatory stress.

Inflammasome-Mediated Cytokines: A Key Connection between Obesity-Associated NASH and Liver Cancer Progression

Liver cancer is one of the most lethal malignancies and is commonly diagnosed as hepatocellular carcinoma (HCC), a tumor type that affects about 90% of patients. Non-alcoholic steatohepatitis (NASH) and obesity are both risk factors for this disease. HCC initiation and progression are deeply linked with changes in the hepatic microenvironment, with cytokines playing key roles. The understanding of the pathogenic pathways that connect these disorders to liver cancer remains poor. However, the inflammasome-mediated cytokines associated with both diseases are central actors in liver cancer progression. The release of the pro-inflammatory cytokines IL-1β and IL-18 during inflammasome activation leads to several detrimental effects on the liver microenvironment. Considering the critical crosstalk between obesity, NASH, and HCC, this review will present the connections of IL-1β and IL-18 from obesity-associated NASH with HCC and will discuss approaches to using these cytokines as therapeutic targets against HCC.

Repression of enhancer RNA PHLDA1 promotes tumorigenesis and progression of Ewing sarcoma via decreasing infiltrating T‐lymphocytes: A bioinformatic analysis

Background: The molecular mechanisms of EWS-FLI-mediating target genes and downstream pathways may provide a new way in the targeted therapy of Ewing sarcoma. Meanwhile, enhancers transcript non-coding RNAs, known as enhancer RNAs (eRNAs), which may serve as potential diagnosis markers and therapeutic targets in Ewing sarcoma.

Materials and methods: Differentially expressed genes (DEGs) were identified between 85 Ewing sarcoma samples downloaded from the Treehouse database and 3 normal bone samples downloaded from the Sequence Read Archive database. Included in DEGs, differentially expressed eRNAs (DEeRNAs) and target genes corresponding to DEeRNAs (DETGs), as well as the differentially expressed TFs, were annotated. Then, cell type identification by estimating relative subsets of known RNA transcripts (CIBERSORT) was used to infer portions of infiltrating immune cells in Ewing sarcoma and normal bone samples. To evaluate the prognostic value of DEeRNAs and immune function, cross validation, independent prognosis analysis, and Kaplan–Meier survival analysis were implemented using sarcoma samples from the Cancer Genome Atlas database. Next, hallmarks of cancer by gene set variation analysis (GSVA) and immune gene sets by single-sample gene set enrichment analysis (ssGSEA) were identified to be significantly associated with Ewing sarcoma. After screening by co-expression analysis, most significant DEeRNAs, DETGs and DETFs, immune cells, immune gene sets, and hallmarks of cancer were merged to construct a co-expression regulatory network to eventually identify the key DEeRNAs in tumorigenesis of Ewing sarcoma. Moreover, Connectivity Map Analysis was utilized to identify small molecules targeting Ewing sarcoma. External validation based on multidimensional online databases and scRNA-seq analysis were used to verify our key findings.

Results: A six-different-dimension regulatory network was constructed based on 17 DEeRNAs, 29 DETFs, 9 DETGs, 5 immune cells, 24 immune gene sets, and 8 hallmarks of cancer. Four key DEeRNAs (CCR1, CD3D, PHLDA1, and RASD1) showed significant co-expression relationships in the network. Connectivity Map Analysis screened two candidate compounds, MS-275 and pyrvinium, that might target Ewing sarcoma. PHLDA1 (key DEeRNA) was extensively expressed in cancer stem cells of Ewing sarcoma, which might play a critical role in the tumorigenesis of Ewing sarcoma.

Conclusion: PHLDA1 is a key regulator in the tumorigenesis and progression of Ewing sarcoma. PHLDA1 is directly repressed by EWS/FLI1 protein and low expression of FOSL2, resulting in the deregulation of FOX proteins and CC chemokine receptors. The decrease of infiltrating T‐lymphocytes and TNFA signaling may promote tumorigenesis and progression of Ewing sarcoma.

Physical Exercise Repairs Obstructive Jaundice-Induced Damage to Intestinal Mucosal Barrier Function via H2S-Mediated Regulation of the HMGB1/Toll Like Receptors 4/Nuclear Factor Kappa B Pathway

The present study aimed to determine the effect of aerobic exercise on improving damage to intestinal mucosal barrier function caused by obstructive jaundice (OJ) and explore the mechanism. Fifty male KM mice were divided into five groups: sham operation group (S), model group (M), exercise group (TM), DL-propargylglycine + exercise (PT) group, and sodium hydrosulfide + exercise (NT) group. Additionally, mice in S group underwent common bile duct ligation for 48 h to establish a murine obstructive jaundice model. In PT group, propargylglycine (40 mg/kg) was intraperitoneally injected 7 days after surgery. NaHS (50 μmol/kg) was intraperitoneally injected into mice in the NT group 7 days after surgery. The TM group, NT group and PT group exercised on a slope of 0% at a speed of 10 m/min without weight training (30 min/day). HE staining showed that the intestinal mucosa of group M was atrophied and that the villi were broken. The intestinal mucosal structure of mice in the TM group was improved. Serum assays showed that H2S levels were higher in the TM group than in the M group; compared with the levels in the TM group, the PT group levels were decreased and the NT group levels were increased. In addition, aerobic exercise inhibits the HMGB1/TLR4/NF-κB signaling pathway by promoting endogenous H2S production, thereby exerting a protective effect on the intestinal mucosal barrier.

Protective effects of 6-gingerol on 6-hydroxydopamine-induced apoptosis in PC12 cells through modulation of SAPK/JNK and survivin activation

Due to many therapeutic effects, Ginger (Zingiber officinale) is the most widely used spice around the world, including in Iran. Due to its potent anti-inflammatory and antioxidant effects, ginger may protect against neurodegenerative disorders. Here, we investigated the effects of 6-gingerol (the main bioactive compound in ginger) on 6-hydroxydopamine (6-OHDA)-induced cell death in PC12 cells. Cell viability, cell apoptosis, and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and survivin expression were measured using resazurin, propidium iodide (PI) and flow cytometry, and western blot analysis. 6-OHDA (100 μM) reduced the cell viability, increased apoptosis, increased the active form of SAPK/JNK, and decreased survivin protein level in PC12 exposed cells in a dose and time-dependent manner. Pretreatment with 6-gingerol significantly increased the viability and reduced apoptosis (2.5 and 5 µM). Also, pretreatment with 6-gingerol at 2.5 and 5 µM increased survivin whereas, 6-gingerol at 2.5 µM reduced (P-SAPK/JNK):(SAPK/JNK) levels to a level near that of the related control. According to the results, 6-gingerol blocks 6-OHDA-induced cell damage by suppressing oxidative stress and anti-apoptotic activity. Thus, 6-gingerol may process beneficial protective effects in slowing the progression of Parkinson's disease.

Inflammation and cancer: paradoxical roles in tumorigenesis and implications in immunotherapies

Chronic inflammation caused by persistent infections and metabolic disorders is thought to contribute to the increased cancer risk and the accelerated cancer progression. Oppositely, acute inflammation induced by bacteria-based vaccines or that is occurring after cancer selectively inhibits cancer progression and metastasis. However, the interaction between inflammation and cancer may be more complex than the current explanations for the relationship between chronic and acute inflammation and cancer. In this review, we described the impact of inflammation on cancer on the basis of three perspectives, including inflammation with different durations (chronic and acute inflammation), different scopes (systemic and local inflammation) and different occurrence sequences (inflammation occurring after and before cancer). In addition, we also introduced bacteria/virus-based cancer immunotherapies. We perceive that inflammation may be a double-edged sword with cancer-promoting and cancer-suppressing functions in certain cases. We expect to further improve the understanding of the relationship between inflammation and cancer and provide a theoretical basis for further research on their complex interaction.

Network pharmacology of triptolide in cancer cells: implications for transcription factor binding

Background Triptolide is an active natural product, which inhibits cell proliferation, induces cell apoptosis, suppresses tumor metastasis and improves the effect of other therapeutic treatments in several cancer cell lines by affecting multiple molecules and signaling pathways, such as caspases, heat-shock proteins, DNA damage and NF-ĸB. Purpose We investigated the effect of triptolide towards NF-ĸB and GATA1. Methods We used cell viability assay, compare and cluster analyses of microarray-based mRNA transcriptome-wide expression data, gene promoter binding motif analysis, molecular docking, Ingenuity pathway analysis, NF-ĸB reporter cell assay, and electrophoretic mobility shift assay (EMSA) of GATA1. Results Triptolide inhibited the growth of drug-sensitive (CCRF-CEM, U87.MG) and drug-resistant cell lines (CEM/ADR5000, U87.MGΔEGFR). Hierarchical cluster analysis showed six major clusters in dendrogram. The sensitive and resistant cell lines were statistically significant (p = 0.65 × 10^-2) distributed. The binding motifs of NF-κB (Rel) and of GATA1 proteins were significantly enriched in regions of 25 kb upstream promoter of all genes. IPA showed the networks, biological functions, and canonical pathways influencing the activity of triptolide towards tumor cells. Interestingly, upstream analysis for the 40 genes identified by compare analysis revealed ZFPM1 (friend of GATA protein 1) as top transcription regulator. However, we did not observe any effect of triptolide to the binding of GATA1 in vitro. We confirmed that triptolide inhibited NF-κB activity, and it strongly bound to the pharmacophores of IκB kinase β and NF-κB in silico. Conclusion Triptolide showed promising inhibitory effect toward NF-κB, making it a potential candidate for targeting NF-κB.

Multi-Arm PEG/Peptidomimetic Conjugate Inhibitors of DR6/APP Interaction Block Hematogenous Tumor Cell Extravasation

The binding of amyloid precursor protein (APP) expressed on tumor cells to death receptor 6 (DR6) could initiate the necroptosis pathway, which leads to necroptotic cell death of vascular endothelial cells (ECs) and results in tumor cells (TCs) extravasation and metastasis. This study reports the first inhibitor of DR6/APP interaction as a novel class of anti-hematogenous metastatic agent. By rationally utilizing three combined strategies including selection based on phage display library, d-retro-inverso modification, and multiple conjugation of screened peptidomimetic with 4-arm PEG, the polymer-peptidomimetic conjugate PEG-tAHP-DRI (tetra-(D-retro-inverso isomer of AHP-12) substitued 4-arm PEG5k ) is obtained as the most promising agent with the strongest binding potency (KD  = 51.12 × 10-9  m) and excellent pharmacokinetic properties. Importantly, PEG-tAHP-DRI provides efficient protection against TC-induced ECs necroptosis both in vitro and in vivo. Moreover, this ligand exhibits prominent anti-hematogenous metastatic activity in serval different metastatic mouse models (B16F10, 4T1, CT26, and spontaneous lung metastasis of 4T1 orthotopic tumor model) and displays no apparent detrimental effects in preliminary safety evaluation. Collectively, this study demonstrates the feasibility of exploiting DR6/APP interaction to regulate hematogenous tumor cells transendothelial migration and provides PEG-tAHP-DRI as a novel and promising inhibitor of DR6/APP interaction for developments of anti-hematogenous metastatic therapies.

IKBKB siRNA-Encapsulated Poly (Lactic-co-Glycolic Acid) Nanoparticles Diminish Neuropathic Pain by Inhibiting Microglial Activation

Activation of nuclear factor-kappa B (NF-κB) in microglia plays a decisive role in the progress of neuropathic pain, and the inhibitor of kappa B (IκB) is a protein that blocks the activation of NF-κB and is degraded by the inhibitor of NF-κB kinase subunit beta (IKBKB). The role of IKBKB is to break down IκB, which blocks the activity of NF-kB. Therefore, it prevents the activity of NK-kB. This study investigated whether neuropathic pain can be reduced in spinal nerve ligation (SNL) rats by reducing the activity of microglia by delivering IKBKB small interfering RNA (siRNA)-encapsulated poly (lactic-co-glycolic acid) (PLGA) nanoparticles. PLGA nanoparticles, as a carrier for the delivery of IKBKB genes silencer, were used because they have shown potential to enhance microglial targeting. SNL rats were injected with IKBKB siRNA-encapsulated PLGA nanoparticles intrathecally for behavioral tests on pain response. IKBKB siRNA was delivered for suppressing the expression of IKBKB. In rats injected with IKBKB siRNA-encapsulated PLGA nanoparticles, allodynia caused by mechanical stimulation was reduced, and the secretion of pro-inflammatory mediators due to NF-κB was reduced. Delivering IKBKB siRNA through PLGA nanoparticles can effectively control the inflammatory response and is worth studying as a treatment for neuropathic pain.

The zinc finger protein Miz1 suppresses liver tumorigenesis by restricting hepatocyte-driven macrophage activation and inflammation

Chronic inflammation plays a central role in hepatocellular carcinoma (HCC), but the contribution of hepatocytes to tumor-associated inflammation is not clear. Here, we report that the zinc finger transcription factor Miz1 restricted hepatocyte-driven inflammation to suppress HCC, independently of its transcriptional activity. Miz1 was downregulated in HCC mouse models and a substantial fraction of HCC patients. Hepatocyte-specific Miz1 deletion in mice generated a distinct sub-group of hepatocytes that produced pro-inflammatory cytokines and chemokines, which skewed the polarization of the tumor-infiltrating macrophages toward pro-inflammatory phenotypes to promote HCC. Mechanistically, Miz1 sequestrated the oncoprotein metadherin (MTDH), preventing MTDH from promoting transcription factor nuclear factor κB (NF-κB) activation. A distinct sub-group of pro-inflammatory cytokine-producing hepatocytes was also seen in a subset of HCC patients. In addition, Miz1 expression inversely correated with disease recurrence and poor prognosis in HCC patients. Our findings identify Miz1 as a tumor suppressor that prevents hepatocytes from driving inflammation in HCC.

Impact of cholesterol-pathways on breast cancer development, a metabolic landscape

ApoB-lipoproteins and their components modulate intracellular metabolism and have been associated with the development of neoplastic phenomena, such as proliferation, anchorage-independent growth, epithelial-mesenchymal transition, and cancer invasion. In cancer cells, the modulation of targets that regulate cholesterol metabolism, such as synthesis de novo, endocytosis, and oxidation, are contributing factors to cancer development. While mechanisms associated with sterol regulatory element-binding protein 2 (SREBP-2)/mevalonate, the low-density lipoprotein receptor (LDL-R) and liver X receptor (LXR) have been linked with tumor growth; metabolites derived from cholesterol-oxidation, such as oxysterols and epoxy-cholesterols, also have been described as tumor processes-inducers. From this notion, we perform an analysis of the role of lipoproteins, their association with intracellular cholesterol metabolism, and the impact of these conditions on breast cancer development, mechanisms that can be shared during atherogenesis promoted mainly by LDL. Pathways connecting plasma dyslipidemias in conjunction with the effect of cholesterol-derived metabolites on intracellular mechanisms and cellular plasticity phenomena could provide new approaches to elucidate the triggering factors of carcinogenesis, conditions that could be considered in the development of new therapeutic approaches.

FGF23 ameliorates ischemia-reperfusion induced acute kidney injury via modulation of endothelial progenitor cells: targeting SDF-1/CXCR4 signaling

The levels of fibroblast growth factor 23 (FGF23) rapidly increases after acute kidney injury (AKI). However, the role of FGF23 in AKI is still unclear. Here, we observe that pretreatment with FGF23 protein into ischemia-reperfusion induced AKI mice ameliorates kidney injury by promoting renal tubular regeneration, proliferation, vascular repair, and attenuating tubular damage. In vitro assays demonstrate that SDF-1 induces upregulation of its receptor CXCR4 in endothelial progenitor cells (EPCs) via a non-canonical NF-κB signaling pathway. FGF23 crosstalks with the SDF-1/CXCR4 signaling and abrogates SDF-1-induced EPC senescence and migration, but not angiogenesis, in a Klotho-independent manner. The downregulated pro-angiogenic IL-6, IL-8, and VEGF-A expressions after SDF-1 infusion are rescued after adding FGF23. Diminished therapeutic ability of SDF-1-treated EPCs is counteracted by FGF23 in a SCID mouse in vivo AKI model. Together, these data highlight a revolutionary and important role that FGF23 plays in the nephroprotection of IR-AKI.

Unraveling the Big Sleep: Molecular Aspects of Stem Cell Dormancy and Hibernation

Tissue-resident stem cells may enter a dormant state, also known as quiescence, which allows them to withstand metabolic stress and unfavorable conditions. Similarly, hibernating mammals can also enter a state of dormancy used to evade hostile circumstances, such as food shortage and low ambient temperatures. In hibernation, the dormant state of the individual and its cells is commonly known as torpor, and is characterized by metabolic suppression in individual cells. Given that both conditions represent cell survival strategies, we here compare the molecular aspects of cellular quiescence, particularly of well-studied hematopoietic stem cells, and torpor at the cellular level. Critical processes of dormancy are reviewed, including the suppression of the cell cycle, changes in metabolic characteristics, and cellular mechanisms of dealing with damage. Key factors shared by hematopoietic stem cell quiescence and torpor include a reversible activation of factors inhibiting the cell cycle, a shift in metabolism from glucose to fatty acid oxidation, downregulation of mitochondrial activity, key changes in hypoxia-inducible factor one alpha (HIF-1α), mTOR, reversible protein phosphorylation and autophagy, and increased radiation resistance. This similarity is remarkable in view of the difference in cell populations, as stem cell quiescence regards proliferating cells, while torpor mainly involves terminally differentiated cells. A future perspective is provided how to advance our understanding of the crucial pathways that allow stem cells and hibernating animals to engage in their 'great slumbers.'

Entolimod as a radiation countermeasure for acute radiation syndrome

High doses of total-body or partial-body radiation exposure can result in a life-threatening acute radiation syndrome as manifested by severe morbidity. Entolimod (CBLB502) is effective in protecting against, and mitigating the development of, the hematopoietic and gastrointestinal subsyndromes of the acute radiation syndrome in rodents and nonhuman primates. Entolimod treatment reduces radiation-induced apoptosis and accelerates the regeneration of progenitors in radiation-damaged tissues. The drug has been evaluated clinically for its pharmacokinetics (PK), toxicity, and biomarkers. The US Food and Drug Administration (FDA) has granted investigational new drug, fast-track, and orphan drug statuses to entolimod. Its safety, efficacy, and animal-to-human dose conversion data allowed its progression with a pre-emergency use authorization application submission.

Cyclophilin A mediates coelomocyte apoptosis via the NF-κB/Bcl-2 signaling pathway in Apostichopus japonicus

As a multifunctional protein, cyclophilin A (CypA) plays an important role in cell apoptosis. In our previous work, we found that CypA from Apostichopus japonicus (AjCypA), as a cofactor, could modulate nuclear translocation of NF-κB. However, the immune function of AjCypA is largely unknown. In the present study, we found that siRNA-mediated AjCypA knockdown in vivo significantly increased the coelomocyte apoptosis rate. In addition, the expression of B-cell lymphoma-2 (AjBcl-2, an anti-apoptosis gene) was synchronously downregulated. To better understand the connection between AjCypA and AjBcl-2 expression, we cloned the promoter of AjBcl-2 via genomic walking, which spanned 1870 bp and contained four potential binding sites of NF-κB. Dual-luciferase reporter assay revealed that the full-length sequence and all truncated fragments exhibited high transcriptional activity. Moreover, 1 μg/mL LPS exposure significantly increased the luciferase activity of P1 (-1870/+57) by 2.31-fold and 3.15-fold at 12 and 24 h, respectively. Furthermore, the four potential NF-κB binding sites and pCMV-Flag2C-AjNF-κB co-transfection assay demonstrated that NF-κB could regulate the expression of AjBcl-2 via the NF-κB binding sites of AjBcl-2 promoter. All results supported that AjCypA mediates coelomocyte apoptosis via NF-κB/AjBcl-2 signaling pathway in A. japonicus.

Modulation of LPS-induced inflammation in RAW264.7 murine cells by novel isoflavonoids from Millettia pulchra

Millettia pulchra is a renowned anti-inflammatory herbal medicine in southeast provinces of China. However, the underlying anti-inflammation mechanism remained incompletely understood. Herein, four new isoflavones, pulvones A-D and eleven reported constituents were isolated from the stems of Millettia pulchra with their structures being elucidated by HRMS and NMR analysis. The anti-inflammatory activities of pulvones A and C were further evaluated due to the better inhibitory activity on nitric oxide production in LPS-stimulated RAW264.7 cells and no obvious cytotoxicity to RAW264.7 cells. Western blot showed that pulvones A significantly decreased the levels of iNOS and COX-2 proteins and pulvones C only decreased the level of iNOS protein. ELISA analysis demonstrated that pulvones A inhibited the production of both interleukin-6 (IL-6) and IL-1β while pulvones C showed better suppression effect on IL-1β production in LPS-stimulated RAW264.7 cells. Then, their potential inhibitory effects on NF-κB pathway were tested in LPS-stimulated RAW264.7 cells. Immunofluorescence and western blot assay showed that pulvones A and C reduced the nuclear translocation of NF-κB(p65) and interrupted IκB phosphorylation. The ADP-Glo™ kinase assay showed pulvones A and C could directedly inhibit the IKKβ kinase activity with the inhibitory rate of 40%, which were also verified by docking study. Collectively, these results suggested that pulvones A and C's anti-inflammatory effects were relevant to the interruption of NF-κB activation by inhibiting IKKβ kinase.

RIPK1 Mediates TNF-Induced Intestinal Crypt Apoptosis During Chronic NF-κB Activation

BACKGROUND AND AIMS

Tumor necrosis factor (TNF) is a major pathogenic effector and a therapeutic target in inflammatory bowel disease (IBD), yet the basis for TNF-induced intestinal epithelial cell (IEC) death is unknown, because TNF does not kill normal IECs. Here, we investigated how chronic nuclear factor (NF)- κB activation, which occurs in human IBD, promotes TNF-dependent IEC death in mice.

METHODS

Human IBD specimens were stained for p65 and cleaved caspase-3. C57BL/6 mice with constitutively active IKKβ in IEC (Ikkβ(EE)^IEC), Ripk1^D138N/D138N knockin mice, and Ripk3^-/- mice were injected with TNF or lipopolysaccharide. Enteroids were also isolated from these mice and challenged with TNF with or without RIPK1 and RIPK3 inhibitors or butylated hydroxyanisole. Ripoptosome-mediated caspase-8 activation was assessed by immunoprecipitation.

RESULTS

NF-κB activation in human IBD correlated with appearance of cleaved caspase-3. Congruently, unlike normal mouse IECs that are TNF-resistant, IECs in Ikkβ(EE)^IEC mice and enteroids were susceptible to TNF-dependent apoptosis, which depended on the protein kinase function of RIPK1. Constitutively active IKKβ facilitated ripoptosome formation, a RIPK1 signaling complex that mediates caspase-8 activation by TNF. Butylated hydroxyanisole treatment and RIPK1 inhibitors attenuated TNF-induced and ripoptosome-mediated caspase-8 activation and IEC death in vitro and in vivo.

CONCLUSIONS

Contrary to common expectations, chronic NF-κB activation induced intestinal crypt apoptosis after TNF stimulation, resulting in severe mucosal erosion. RIPK1 kinase inhibitors selectively inhibited TNF destructive properties while preserving its survival and proliferative properties, which do not require RIPK1 kinase activity. RIPK1 kinase inhibition could be a potential treatment for IBD.

Apoptosis-promoting and migration-suppressing effect of alantolactone on gastric cancer cell lines BGC-823 and SGC-7901 via regulating p38MAPK and NF-κB pathways

BACKGROUND

Gastric cancer is a malignant tumor with high incidence rate and mortality rate.

PURPOSE

In this study, we investigated the anti-cancer effect of alantolactone, a sesquiterpene lactone, on gastric cancer cell lines BGC-823 and SGC-7901.

METHODS

BGC-823 and SGC-7901 cells were treated with different concentrations of alantolactone, Hoechst 33258 staining, flow cytometry, wound healing assay, invasion assay, colony forming assay, quantative polymerase chain reaction, and western blot analysis were used to evaluate the anticancer activity of alantolactone to gastric cancer.

RESULTS

Alantolactone induced apoptosis of gastric cancer cells by regulating the expression of Bax, Bcl-2, and p53, which related to intrinsic apoptotic pathway, and suppressed colony formation, migration, and invasion by mediating the expression of matrix metalloproteinase (MMP)-2, MMP-7, and MMP-9. Cell signaling pathway analysis showed that alantolactone enhanced the phosphorylation of p38 and decreased the translocation of nucleus p65, suggesting that the apoptosis-promoting and migration-suppressing effect of alantolactone might at least partially rely on regulating p38 mitogen-activated protein kinase (p38MAPK) pathway and nuclear factor-κB (NF-κB) pathway.

CONCLUSIONS

Alantolactone can be used as a potential therapeutic agent for treating gastric cancer.

Phospho Tensin Homolog in Human and Lipid Peroxides in Peripheral Blood Mononuclear Cells Following Exposure to Flavonoids

Objectives: Studies have shown that human and peripheral blood mononuclear cells (PBMCs) are mostly used for research purposes to study several biochemical endpoints. The effects of the flavonoids, genistein, kaempferol, and quercetin on phospho tensin homolog (PTEN) levels in cancer cells (i.e., breast [BT549], lung [A549]), human embryonic kidney cells (HEK293), and the levels of lipid peroxides (LP) in PBMCs were respectively investigated.Materials and methods: Cancer, kidney, and PBMCs from several donors were each exposed to each of the flavonoids at concentrations of 0, 5, 10, 15, 20, and 25 µM. Our hypotheses were that exposure of cancer and kidney cells to genistein, kaempferol, and quercetin can increase PTEN and decrease lipid peroxides in PBMCs levels respectively to better cope with oxidative stress.Results: The results indicate that the flavonoids increased total PTEN levels in a dose-dependent manner. The effect of quercetin was more pronounced followed by genistein and kaempferol. Furthermore, decreases in lipid peroxides were observed in the PBMCs for the flavonoid-treated samples compared to those exposed to flavonoids and with oxidative stress as described by Fenton's chemistry. Levels of LP in quercetin-treated samples were lower compared to kaempferol and genistein.Conclusions: The findings suggest that the flavonoids play an important role in controlling oxidative stress in several human cells.

Collateral Sensitivity of Parthenolide via NF-κB and HIF-α Inhibition and Epigenetic Changes in Drug-Resistant Cancer Cell Lines

Parthenolide (PT) is a sesquiterpene lactone isolated from Tanacetum parthenium. In this study, PT showed varying cytotoxic effects against different solid tumor cell lines. HCT116 (p53^+/+) colon carcinoma cells and their parental HCT116 knockout p53 (p53^-/-) cell lines showed a resistance degree of 2.36. On the other hand, wild-type U87.MG cells or cells transfected with a deletion-activated EGFR cDNA (U87.MGΔEGFR) exhibited slight sensitivity toward PT. Multidrug-resistant MDA-MB-231-BCRP cells were even more sensitive toward PT than sensitive MDA-MB-231-pcDNA cells with a resistance degree of 0.07 (collateral sensitivity). To the best of our knowledge, hypersensitivity (collateral sensitivity) in MDA-MB-231-BCRP cell line is reported in this study for the first time. We attempted to identify the mechanism of collateral sensitivity. Firstly, we found that PT bound to IKK preventing IκBα degradation and eventually inhibition of the nuclear factor kappa B (NF-κB) pathway. Down-regulation of hypoxia inducing factor 1-alpha (HIF-1α) in MDA-MB-231-BCRP resistant cells may be a second mechanism, since it is a target gene of NF-κB. Moreover, PT also showed epigenetic effect by inhibition of HDAC activity as shown using both molecular docking and HDAC activity assay. Based on COMPARE and hierarchical cluster analyses, we found gene expression profiles that predicted sensitivity or resistance of 47 tumor cell lines toward PT. Interestingly, pathway analyses of gene expression profiles revealed NF-κB and HIF signaling as top networks of these genes, cellular functions and canonical pathways influencing the activity of PT against tumor cells. In conclusion, PT exerted profound cytotoxic activity against various cancer cell lines mainly against BCRP-overexpressing tumor cells, suggesting PT as novel candidate for cancer treatment.

Dysregulation of Intestinal Epithelial Cell RIPK Pathways Promotes Chronic Inflammation in the IBD Gut

Crohn's disease (CD) and ulcerative colitis (UC) are common intestinal bowel diseases (IBD) characterized by intestinal epithelial injury including extensive epithelial cell death, mucosal erosion, ulceration, and crypt abscess formation. Several factors including activated signaling pathways, microbial dysbiosis, and immune deregulation contribute to disease progression. Although most research efforts to date have focused on immune cells, it is becoming increasingly clear that intestinal epithelial cells (IEC) are important players in IBD pathogenesis. Aberrant or exacerbated responses to how IEC sense IBD-associated microbes, respond to TNF stimulation, and regenerate and heal the injured mucosa are critical to the integrity of the intestinal barrier. The role of several genes and pathways in which single nucleotide polymorphisms (SNP) showed strong association with IBD has recently been studied in the context of IEC. In patients with IBD, it has been shown that the expression of specific dysregulated genes in IECs plays an important role in TNF-induced cell death and microbial sensing. Among them, the NF-κB pathway and its target gene TNFAIP3 promote TNF-induced and receptor interacting protein kinase (RIPK1)-dependent intestinal epithelial cell death. On the other hand, RIPK2 functions as a key signaling protein in host defense responses induced by activation of the cytosolic microbial sensors nucleotide-binding oligomerization domain-containing proteins 1 and 2 (NOD1 and NOD2). The RIPK2-mediated signaling pathway leads to the activation of NF-κB and MAP kinases that induce autophagy following infection. This article will review these dysregulated RIPK pathways in IEC and their role in promoting chronic inflammation. It will also highlight future research directions and therapeutic approaches involving RIPKs in IBD.

Drug discovery strategies for acute radiation syndrome

Introduction: There are at the minimum two major, quite different approaches to advance drug discovery. The first being the target-based drug discovery (TBDD) approach that is commonly referred to as the molecular approach. The second approach is the phenotype-based drug discovery (PBDD), also known as physiology-based drug discovery or empirical approach. Area covered: The authors discuss, herein, the need for developing radiation countermeasure agents for various sub-syndromes of acute radiation syndromes (ARS) following TBDD and PBDD approaches. With time and continuous advances in radiation countermeasure drug development research, the expectation is to have multiple radiation countermeasure agents for each sub-syndrome made available to radiation exposed victims. Expert opinion: The majority of the countermeasures currently being developed for ARS employ the PBDD approach, while the TBDD approach is clearly under-utilized. In the future, an improved drug development strategy might be a 'hybrid' strategy that is more reliant on TBDD for the initial drug discovery via large-scale screening of potential candidate agents, while utilizing PBDD for secondary screening of those candidates, followed by tertiary analytics phase in order to pinpoint efficacious candidates that target the specific sub-syndromes of ARS.

Potential use of melatonin in skin cancer treatment: A review of current biological evidence

Skin cancer, particularly melanoma, is a leading cause of death worldwide. The therapeutic methods for this malignancy are not effective, and due to the side effects of these treatments, applying an appropriate alternative or complementary treatment is important. According to available data, melatonin as the main product of the pineal gland has oncostatic and antitumoral properties. Also, melatonin acts as an anti-inflammatory and reactive oxygen species inducer agent which suppresses the growth of tumors. It also has apoptosis induction characteristics through regulating signaling pathways, including heat shock protein 70, nuclear factor-erythroid 2 p45-related factor 2 and others. Thus, adding melatonin to chemo- and radiotherapy may have synergistic therapeutic effects and increase the survival time in patients with skin cancer. Few clinical studies have evaluated the efficacy of melatonin in skin cancer. Based on the related mechanisms, this review discusses about how melatonin may improve outcomes in skin cancer patients.

The inflammatory cytokine TNF contributes with RAC3-induced malignant transformation

RAC3 is a coactivator of steroid receptors and NF-κB. It is usually overexpressed in several tumors, contributes to maintain cancer stem cells and also to induce them when is overexpressed in non-tumoral cells. In this work, we investigated whether the inflammatory cytokine TNF may contribute to the transforming effects of RAC3 overexpression in the non-tumoral HEK293 cell line.

The study model included the HEK293 tumoral transformed cell line constitutively overexpressing RAC3 by stable transfection and control non-tumoral cells transfected with an empty vector. The HeLa and T47D tumoral cells that naturally overexpress RAC3 were used as positive control.

We found that TNF potentiated RAC3-induced mesenchymal transition, involving an increased E-Cadherin downregulation, Vimentin and SNAIL upregulation and enhanced migratory behavior. Moreover, concerning the molecular mechanisms by which TNF potentiates the RAC3 transforming action, they involve the IKK activation, which in addition induced the β-Catenin transactivation.

Our results demonstrate that although RAC3 overexpression could be a signal strong enough to induce cancer stem cells, the inflammatory microenvironment may be playing a key role contributing to the migratory and invasive phenotype required for metastasis and cancer persistence.

Protective and therapeutic potential of ginger (Zingiber officinale) extract and [6]-gingerol in cancer: A comprehensive review

Natural dietary agents have attracted considerable attention due to their role in promoting health and reducing the risk of diseases including cancer. Ginger, one of the most ancient known spices, contains bioactive compounds with several health benefits. [6]-Gingerol constitutes the most pharmacologically active among such compounds. The aim of the present work was to review the literature pertaining to the use of ginger extract and [6]-gingerol against tumorigenic and oxidative and inflammatory processes associated with cancer, along with the underlying mechanisms of action involved in signaling pathways. This will shed some light on the protective or therapeutic role of ginger derivatives in oxidative and inflammatory regulations during metabolic disturbance and on the antiproliferative and anticancer properties. Data collected from experimental (in vitro or in vivo) and clinical studies discussed in this review indicate that ginger extract and [6]-gingerol exert their action through important mediators and pathways of cell signaling, including Bax/Bcl2, p38/MAPK, Nrf2, p65/NF-κB, TNF-α, ERK1/2, SAPK/JNK, ROS/NF-κB/COX-2, caspases-3, -9, and p53. This suggests that ginger derivatives, in the form of an extract or isolated compounds, exhibit relevant antiproliferative, antitumor, invasive, and anti-inflammatory activities.

Elevated A20 promotes TNF-induced and RIPK1-dependent intestinal epithelial cell death

Intestinal epithelial cell (IEC) death is a common feature of inflammatory bowel disease (IBD) that triggers inflammation by compromising barrier integrity. In many patients with IBD, epithelial damage and inflammation are TNF-dependent. Elevated TNF production in IBD is accompanied by increased expression of the TNFAIP3 gene, which encodes A20, a negative feedback regulator of NF-κB. A20 in intestinal epithelium from patients with IBD coincided with the presence of cleaved caspase-3, and A20 transgenic (Tg) mice, in which A20 is expressed from an IEC-specific promoter, were highly susceptible to TNF-induced IEC death, intestinal damage, and shock. A20-expressing intestinal organoids were also susceptible to TNF-induced death, demonstrating that enhanced TNF-induced apoptosis was a cell-autonomous property of A20. This effect was dependent on Receptor Interacting Protein Kinase 1 (RIPK1) activity, and A20 was found to associate with the Ripoptosome complex, potentiating its ability to activate caspase-8. A20-potentiated RIPK1-dependent apoptosis did not require the A20 deubiquitinase (DUB) domain and zinc finger 4 (ZnF4), which mediate NF-κB inhibition in fibroblasts, but was strictly dependent on ZnF7 and A20 dimerization. We suggest that A20 dimers bind linear ubiquitin to stabilize the Ripoptosome and potentiate its apoptosis-inducing activity.

A Herpes Simplex Virus Thymidine Kinase-Induced Mouse Model of Hepatocellular Carcinoma Associated with Up-Regulated Immune-Inflammatory-Related Signals

Inflammation and fibrosis in human liver are often precursors to hepatocellular carcinoma (HCC), yet none of them is easily modeled in animals. We previously generated transgenic mice with hepatocyte-specific expressed herpes simplex virus thymidine kinase (HSV-tk). These mice would develop hepatitis with the administration of ganciclovir (GCV)(Zhang, 2005 #1). However, our HSV-tk transgenic mice developed hepatitis and HCC tumor as early as six months of age even without GCV administration. We analyzed the transcriptome of the HSV-tk HCC tumor and hepatitis tissue using microarray analysis to investigate the possible causes of HCC. Gene Ontology (GO) enrichment analysis showed that the up-regulated genes in the HCC tissue mainly include the immune-inflammatory and cell cycle genes. The down-regulated genes in HCC tumors are mainly concentrated in the regions related to lipid metabolism. Gene set enrichment analysis (GSEA) showed that immune-inflammatory-related signals in the HSV-tk mice are up-regulated compared to those in Notch mice. Our study suggests that the immune system and inflammation play an important role in HCC development in HSV-tk mice. Specifically, increased expression of immune-inflammatory-related genes is characteristic of HSV-tk mice and that inflammation-induced cell cycle activation maybe a precursory step to cancer. The HSV-tk mouse provides a suitable model for the study of the relationship between immune-inflammation and HCC, and their underlying mechanism for the development of therapeutic application in the future.

Immunostaining Study on the Expression of NF-κB, ER, and PR in Ovarian Serous Carcinoma

In order to explore whether NF-κB activation correlates to the prognosis, chemoresistance, and sex hormone receptors status in ovarian serous carcinoma, we analyzed the expression of NF-κB, ER, and PR by immunohistochemistry in 72 cases of ovarian serous carcinoma, investigated the association among these markers, and evaluated their relations to clinicopathologic factors and prognosis. The positive rates were 88.9% for NF-κB cytoplasmic expression, 45.8% for NF-κB nuclear expression, 41.7% for ER, and 29.2% for PR. NF-κB nuclear expression was positively correlated with the 4th edition WHO grade (P=0.045) and tumor stage (P=0.001). NF-κB cytoplasmic expression was associated with preoperative serum CA125 level (P=0.015) and ascites (P=0.042). Neither cytoplasmic nor nuclear staining of NF-κB showed any association with survival. PR expression was correlated with tumor stage (P=0.023) and omental metastasis (P=0.022). Omental metastasis occurred more frequently in ER-/PR- tumors (P=0.009). No correlation between NF-κB expression and ER, PR expression was observed. In conclusion, in ovarian serous carcinoma, NF-κB nuclear expression correlated with the 4th edition WHO grade and PR was a favorable prognostic factor for ovarian serous carcinoma.

The STAT3 Target Gene TNFRSF1A Modulates the NF-κB Pathway in Breast Cancer Cells

The transcription factor STAT3 is activated inappropriately in 70% of breast cancers, most commonly in triple negative breast cancer (TNBC). Although the transcriptional function of STAT3 is essential for tumorigenesis, the key target genes regulated by STAT3 in driving tumor pathogenesis have remained unclear. To identify critical STAT3 target genes, we treated TNBC cell lines with two different compounds that block STAT3 transcriptional function, pyrimethamine and PMPTP. We then performed gene expression analysis to identify genes whose expression is strongly down-regulated by both STAT3 inhibitors. Foremost among the down-regulated genes was TNFRSF1A, which encodes a transmembrane receptor for TNFα. We showed that STAT3 binds directly to a regulatory region within the TNFRSF1A gene, and that TNFRSF1A levels are dependent on STAT3 function in both constitutive and cytokine-induced models of STAT3 activation. Furthermore, TNFRSF1A is a major mediator of both basal and TNFα-induced NF-κB activity in breast cancer cells. We extended these findings to primary human breast cancers, in which we found that high TNFRSF1A transcript levels correlated with STAT3 activation. In addition, and consistent with a causal role, increased TNFRSF1A expression was associated with an NF-κB gene expression in signature in breast cancers. Thus, TNFRSF1A is a STAT3 target gene that regulates the NF-κB pathway. These findings reveal a novel functional crosstalk between STAT3 and NF-κB signaling in breast cancer. Furthermore, elevated TNFRSF1A levels may predict a subset of breast tumors that are sensitive to STAT3 transcriptional inhibitors, and may be a biomarker for response to inhibition of this pathway.

Nebulized lidocaine ameliorates allergic airway inflammation via downregulation of TLR2

Nebulized lidocaine has been suggested to be beneficial in asthma therapy, but the underlying mechanisms are little known. We aimed to investigate whether Toll-like receptor (TLR) 2 was involved in the protective effect of lidocaine on allergic airway inflammation. Female C57BL/6 mice were sensitized and challenged with ovalbumin (OVA). Meanwhile, some of the mice were treated with TLR2 agonist (Pam3CSK4, 100 μg) intraperitoneally in combination with OVA on day 0. Just after allergen provocation, mice were treated with inhaled lidocaine or vehicle for 30 min. In this model, we found that lidocaine markedly attenuated OVA-evoked airway inflammation, leukocyte recruitment and mucus production. Moreover, lidocaine abrogated the increased concentrations of T cytokines and TNF-α in bronchoalveolar lavage fluid (BALF) of allergic mice, as well as reducing the expression of phosphorylated nuclear factor (P-NF)-κBp65 and the NOD-like receptor pyridine containing 3 (NLRP3), which are important for the production of pro-inflammatory cytokines. In addition, our study showed that lidocaine dramatically decreased OVA-induced increased expression of TLR2 in the lung tissues. Furthermore, activation of TLR2 aggravated OVA-challenged airway inflammation, meanwhile, it also elevated OVA-induced expression of P-NF-κBp65 and NLRP3 in the lungs. However, lidocaine effectively inhibited airway inflammation and counteracted the expression of P-NF-κBp65 and NLRP3 in allergic mice pretreated with Pam3CSK4. Taken together, the present study demonstrated that lidocaine prevented allergic airway inflammation via TLR2 in an OVA-induced murine allergic airway inflammation model. TLR2/NF-κB/NLRP3 pathway may serve as a promising therapeutic strategy for allergic airway inflammation.

Uev1A-Ubc13 promotes colorectal cancer metastasis through regulating CXCL1 expression via NF-кB activation

Colorectal cancer is the second most common cause of cancer-related death worldwide. Uncontrolled growth and distant metastasis are hallmarks of colorectal cancer. However, the precise etiological factors and the mechanisms are diverse and still largely unclear. The potential proto-oncogene UEV1A encodes a ubiquitin conjugating enzyme variant, which is required for Ubc13-catalyzed K63-linked poly-ubiquitination of target proteins and the activation of NF-кB, a transcription factor known to be involved in innate immunity, anti-apoptosis, inflammation and cancer. In order to understand the roles of Uev1A in colon cancer progression, we experimentally manipulated the Uev1A level in HCT116 colon cancer cells and found that UEV1A overexpression alone is sufficient to promote invasion in vitro and metastasis in vivo. This process is mediated by NF-κB activation and depends on its physical interaction with Ubc13. No expression of Uev1A was detected in histologically normal human colonic mucosa, but its expression was detected in human colorectal adenocarcinoma, which was closely correlated with nuclear p65 levels, an indicator of NF-κB activation. Uev1A protein was detected in 46% of primary tumors and 79% of metastatic tumors examined. Our experimental data establish that among NF-κB target genes, Uev1A-regulated CXCL1 expression plays a critical role in colon cell invasion and metastasis, a notion supported by the colon adenocarcinoma survey. Furthermore, experimental depletion of Uev1 in HCT116 cells reduces CXCL1 expression, and prevents cell invasion and tumor growth in a xenograft mouse model. These results identify Uev1A as a potential therapeutic target in the treatment of metastatic colorectal cancers.

Functional miRNAs in breast cancer drug resistance

Owing to improved early surveillance and advanced therapy strategies, the current death rate due to breast cancer has decreased; nevertheless, drug resistance and relapse remain obstacles on the path to successful systematic treatment. Multiple mechanisms responsible for drug resistance have been elucidated, and miRNAs seem to play a major part in almost every aspect of cancer progression, including tumorigenesis, metastasis, and drug resistance. In recent years, exosomes have emerged as novel modes of intercellular signaling vehicles, initiating cell–cell communication through their fusion with target cell membranes, delivering functional molecules including miRNAs and proteins. This review particularly focuses on enumerating functional miRNAs involved in breast cancer drug resistance as well as their targets and related mechanisms. Subsequently, we discuss the prospects and challenges of miRNA function in drug resistance and highlight valuable approaches for the investigation of the role of exosomal miRNAs in breast cancer progression and drug resistance.

BCSC-1 suppresses human breast cancer metastasis by inhibiting NF-κB signaling

Breast cancer suppressor candidate-1 (BCSC-1; also termed von Willebrand factor A domain containing 5A and LOH11CR2A) is a newly identified candidate tumor suppressor gene that has been implicated in several types of cancer in previous studies. However, there have been few reports about the association between BCSC-1 and human breast cancer in recent years. In the present study, the expression of BCSC-1 in breast cancer was determined by immunohistochemistry (IHC) staining of tissue microarrays and clinical tissue specimens. Subsequently, BCSC-1 gene expression was evaluated in different breast cancer cell lines by quantitative polymerase chain reaction and the MDA-MB-231 cell line was selected for further use in subsequent experiments, due to its low BCSC-1 expression. An MDA-MB-231 cell line with stable overexpression of BCSC-1 was established through transfection with plasmid containing the BCSC-1 gene, and then screening for G418 resistance. Wound-healing, migration and invasion assays were conducted to detect the effect of BCSC-1 on MDA-MB-231 cells. Furthermore, changes in matrix metalloproteinases (MMPs), osteopontin (OPN) and the nuclear factor-κB (NF-κB) pathway were detected in the current study. Additionally, stable silencing of BCSC-1 expression in MCF-7 cells was performed using a lentivirus. The results of IHC indicated that BCSC-1 is expressed at low levels in breast cancer tissues compared with in normal breast tissue. Results of the wound healing, migration and invasion assays demonstrated that BCSC-1 overexpression reduced the metastasis ability of MDA-MB-231 cells in vitro. Further research confirmed that the BCSC-1 overexpression reduced the expression levels of MMP7, MMP9 and OPN, and the phosphorylation of NF-κB p65. Furthermore, inhibition of BCSC-1 via lentivirus-mediated RNA interference revealed that the downregulation of BCSC-1 increased the invasive ability of MCF-7 cells. In summary, the results demonstrated that BCSC-1 is expressed at low levels in breast cancer tissues, and that it can suppress human breast cancer cell migration and invasion, potentially altering the expression of MMP7, MMP9, OPN, and the activity of the NF-κB pathway. Therefore, BCSC-1 may be useful as a biomarker for the treatment of breast cancer in the future.

NF-κB in the crosshairs: Rethinking an old riddle

Constitutive NF-κB signalling has been implicated in the pathogenesis of most human malignancies and virtually all non-malignant pathologies. Accordingly, the NF-κB pathway has been aggressively pursued as an attractive therapeutic target for drug discovery. However, the severe on-target toxicities associated with systemic NF-κB inhibition have thus far precluded the development of a clinically useful, NF-κB-targeting medicine as a way to treat patients with either oncological or non-oncological diseases. This minireview discusses some of the more promising approaches currently being developed to circumvent the preclusive safety liabilities of global NF-κB blockade by selectively targeting pathogenic NF-κB signalling in cancer, while preserving the multiple physiological functions of NF-κB in host defence responses and tissue homeostasis.

Immunostimulatory effects of sulfated chitosans on RAW 264.7 mouse macrophages via the activation of PI3K/Akt signaling pathway

To investigate the immunostimulatory effects of chitosan sulfates, we prepared α- and β-chitosan sulfates with different molecular weights and compared their immunostimulatory activities in RAW 264.7 macrophages. Results suggest that β-chitosan sulfates were more active than α-chitosan in promoting nitric oxide (NO) production. Further study show that β-chitosan sulfate significantly promoted the production of NO, prostaglandin E₂, tumor necrosis factor (TNF)-α, interleukin-6 and interleukin-1β at the levels of transcription and translation. Moreover, Western blots revealed that it induced the phosphorylation of p85 and Akt, and the nuclear translocation of p50/p65 and c-Fos/c-Jun. The luciferase activity of cells pretreated with β-chitosan sulfate further confirmed the nuclear translocation of p50/p65 and c-Fos/c-Jun. Determination of Toll-like receptor (TLR) 4 expression suggested that β-chitosan sulfate at least partly bound to TLR4. In conclusion, β-chitosan sulfates activate RAW 264.7 cells through the PI3K-Akt pathway, which is dependent on activator protein-1 and nuclear factor-κB activation.

Comparison of Two Components of Propolis: Caffeic Acid (CA) and Caffeic Acid Phenethyl Ester (CAPE) Induce Apoptosis and Cell Cycle Arrest of Breast Cancer Cells MDA-MB-231

Studies show that caffeic acid (CA) and caffeic acid phenethyl ester (CAPE) are compounds with potent chemopreventive effects. Breast cancer is a common form of aggressive cancer among women worldwide. This study shows a comparison of CA and CAPE activity on triple-negative human caucasian breast adenocarcinoma line cells (MDA-MB-231). MDA-MB-231 cells were treated by CA and CAPE with doses of from 10 to 100 µM, for periods of 24 h and 48 h. Cytotoxicity MTT tests, apoptosis by Annexin V, and cell cycle with Dead Cell Assays were performed. Cytotoxic activity was greater for CAPE compared to CA (both incubation times, same dosage). IC₅₀ values for CAPE were 27.84 µM (24 h) and 15.83 µM (48 h) and for CA > 10,000 µM (24 h) and > 1000 µM (48 h). Polyphenols induced apoptosis, while CAPE (dose dependently), induced a higher apoptotic effect. CAPE also induced cell cycle arrest in S phase (time and dose dependently), CA did it only for 50 and 100 µM. A dose dependent decline was seen for the G0/G1 phase (CAPE, 48 h), as well as elimination of phase G2/M by 100 µM of CAPE (only mild effect for CA). Comparing CA and CAPE activity on MDA-MB-231, CAPE clearly showed better activity for the same dosages and experiment times.

Limiting inflammation-the negative regulation of NF-κB and the NLRP3 inflammasome

A properly mounted immune response is indispensable for recognizing and eliminating danger arising from foreign invaders and tissue trauma. However, the 'inflammatory fire' kindled by the host response must be tightly controlled to prevent it from spreading and causing irreparable damage. Accordingly, acute inflammation is self-limiting and is normally attenuated after elimination of noxious stimuli, restoration of homeostasis and initiation of tissue repair. However, unresolved inflammation may lead to the development of chronic autoimmune and degenerative diseases and cancer. Here, we discuss the key molecular mechanisms that contribute to the self-limiting nature of inflammatory signaling, with emphasis on the negative regulation of the NF-κB pathway and the NLRP3 inflammasome. Understanding these negative regulatory mechanisms should facilitate the development of much-needed therapeutic strategies for treatment of inflammatory and autoimmune pathologies.

Pteisolic acid G, a novel ent-kaurane diterpenoid, inhibits viability and induces apoptosis in human colorectal carcinoma cells

Human colorectal cancer (CRC) is a major cause of cancer morbidity and mortality, and its incidence rates are increasing in economical transitioning areas globally. To develop efficient chemotherapy drugs for CRC, the present study isolated and identified a novel ent-kaurane diterpenoid from Pteris semipinnata, termed pterisolic acid G (PAG). This ent-kaurane diterpenoid was demonstrated to significantly inhibit the growth of human CRC HCT116 cells in a time- and dose-dependent manner, determined using the Cell Counting Kit-8 assay. Additionally, western blot analysis, Hoechst 33342 staining and cytometry analysis revealed that PAG not only inhibited the viability of HCT116 cells by suppressing the dishevelled segment polarity protein 2/glycogen synthase kinase 3 β/β-catenin pathway, but also induced the apoptosis of HCT116 cells by downregulating nuclear factor-κB p65 activity, stimulating p53 expression and promoting the generation of intracellular reactive oxygen species. These results suggest that PAG, a novel inhibitor of the Wnt/β-catenin pathway and inducer of apoptosis, should be investigated in more detail using in vivo experiments and comprehensive mechanistic studies in order to examine the potential use of PAG as a novel therapeutic agent for the treatment of CRC.

Activation of the HMGB1‑TLR4‑NF‑κB pathway may occur in patients with atopic eczema

High mobility group protein B1 (HMGB1) has been reported to serve important roles in various pathological conditions. Toll‑like receptor 4 (TLR4), as one of the HMGB1 receptors, has been reported to be involved in the development of certain inflammatory diseases by activating nuclear factor NF‑κ‑B (NF‑κB). However, there are few studies investigating the effects of HMGB1, TLR4 and NF‑κB on human inflammatory dermatoses. In the present study, the distribution and characteristics of HMGB1, TLR4 and NF‑κB p65 expression in psoriasis and atopic eczema (AE) were investigated. In addition, immunohistochemical analysis was performed to evaluate their expression and distribution in normal skin, and in patients with AE or psoria-sis. Spearman's correlation analysis was used to predicate their relevancy. The present study identified that the p65 level in epithelial nuclei in AE skin was increased compared with normal and psoriasis skin (P<0.01). The level of extracellular HMGB1 in AE skin was also increased compared with normal and psoriasis skin (P<0.01). Meanwhile, TLR4 expression on the epithelial membranes of AE skin was increased compared with psoriasis skin (P<0.01). Furthermore, the level of extracellular HMGB1 was positively correlated with epithelial membrane TLR4 (r=0.3856; P<0.05) and epithelial nuclear p65 (r=0.5894; P<0.01) in AE skin. These results indicated that the HMGB1‑TLR4‑NF‑κB signaling pathway is activated in AE and may account for its pathogenesis, but not in psoriasis. Therefore, HMGB1, TLR4 and NF‑κB p65 have the potential to be targets for the treatment of human inflammatory dermatoses, including AE.

A Fas Ligand (FasL)-Fused Humanized Antibody Against Tumor-Associated Glycoprotein 72 Selectively Exhibits the Cytotoxic Effect Against Oral Cancer Cells with a Low FasL/Fas Ratio

Altered expression of the Fas ligand (FasL)/Fas ratio exhibits a direct impact on the prognosis of cancer patients, and its impairment in cancer cells may lead to apoptosis resistance. Thus, the development of effective therapies targeting the FasL/Fas system may play an important role in the fight against cancer. In this study, we evaluated whether a fusion protein (hcc49scFv-FasL) comprising of the cytotoxicity domain of the FasL fused to a humanized antibody (CC49) against tumor-associated glycoprotein 72, which is expressed on oral squamous cell carcinoma (OSCC), can selectively kill OSCC cells with different FasL/Fas ratios. In clinical samples, the significantly low FasL and high Fas transcripts were observed in tumors compared with normal tissues. A lower FasL/Fas ratio was correlated with a worse prognosis of OSCC patients and higher proliferative and invasive abilities of OSCC cells. The hcc49scFv-FasL showed a selective cytotoxic effect on OSCC cells (Cal-27 and SAS) but not on normal oral keratinocytes cells (HOK) through apoptosis induction. Moreover, SAS cells harboring a lower FasL/Fas ratio than Cal-27 were more sensitive to the cytotoxic effect of hcc49scFv-FasL. Unlike wild-type FasL, hcc49scFv-FasL was not cleaved by matrix metalloproteinases and did not induce nonapoptotic signaling in SAS cells. In vivo, we found that hcc49scFv-FasL drastically reduced the formation of lymph node metastasis and decreased primary tumor growth in SAS orthotopic and subcutaneous xenograft tumor models. Collectively, our data indicate that a tumor-targeting antibody fused to the FasL can be a powerful tool for OSCC treatment, especially in populations with a low FasL/Fas ratio. Mol Cancer Ther; 16(6); 1102-13. ©2017 AACR.

Autocrine and Paracrine Mechanisms Promoting Chemoresistance in Cholangiocarcinoma

Resistance to conventional chemotherapeutic agents, a typical feature of cholangiocarcinoma, prevents the efficacy of the therapeutic arsenal usually used to combat malignancy in humans. Mechanisms of chemoresistance by neoplastic cholangiocytes include evasion of drug-induced apoptosis mediated by autocrine and paracrine cues released in the tumor microenvironment. Here, recent evidence regarding molecular mechanisms of chemoresistance is reviewed, as well as associations between well-developed chemoresistance and activation of the cancer stem cell compartment. It is concluded that improved understanding of the complex interplay between apoptosis signaling and the promotion of cell survival represent potentially productive areas for active investigation, with the ultimate aim of encouraging future studies to unveil new, effective strategies able to overcome current limitations on treatment.

Anticancer activity of Nelumbo nucifera stamen extract in human colon cancer HCT-116 cells in vitro

The aim of the present study was to investigate the anticancer activities of Nelumbo nucifera (Ba lotus) stamen ethanol crude extract (BLSEE) in human colon carcinoma HCT-116 cells. MTT assay, flow cytometry analysis and reverse transcription-polymerase chain reaction assay were employed to investigate the anticancer mechanisms of BLSEE (100, 200 and 400 µg/ml) in HCT-116 cells. BLSEE reduced HCT-116 cell proliferation in a dose-dependent manner. BLSEE treatment also significantly increased the sub-G1 population in HCT-116 cells (P=0.0020 at 400 µg/ml), as shown by flow cytometry assay. Following treatment with BLSEE, the mRNA levels of the apoptosis-associated factors Fas, Fas ligand, tumor necrosis factor-related apoptosis-inducing ligand, death receptor 4 (DR4), death receptor 5 (DR5), caspases 3, 8 and 9, and B-cell lymphoma-2 (Bcl-2) associated X protein were increased, and the expression of anti-apoptotic Bcl-2 and Bcl-extra large was decreased in HCT-116 cells. The mRNA levels of matrix metalloproteinase (MMP)-2, MMP-9, TIMP metallopeptidase inhibitor 1 and TIMP metallopeptidase inhibitor 2 were also regulated by BLSEE treatment. In addition, BLSEE was able to modulate the expression of inflammation-associated nuclear factor-κB, inhibitory κBα, inducible nitric oxide synthase and cyclooxygenase 2 in HCT-116 cells. The present study clearly indicated the cytotoxicity of BLSEE in HCT-116 cells through induced cellular apoptosis. These results also suggested the BLSEE may be a powerful agent against colon cancer cells.

Anticancer activities of alkaloids extracted from the Ba lotus seed in human nasopharyngeal carcinoma CNE-1 cells

To investigate the anticancer activities of alkaloids from the Ba lotus seed (BLSA) in human nasopharyngeal carcinoma (NPC) CNE-1 cells, an MTT assay, flow cytometry, reverse transcription-polymerase chain reaction and western blotting were performed. BLSA was found to significantly reduce CNE-1 cell proliferation in a dose-dependent manner at all concentrations compared with the control (P<0.05). In addition, flow cytometry analysis identified that BLSA treatment significantly increased the sub-G1 content in CNE-1 cells (P<0.05). Following BLSA treatment, the mRNA and protein levels of a number of apoptosis-related factors, such as caspase family members (caspase-3, -8 and -9), B-cell lymphoma (Bcl)-2-associated X protein, Fas and Fas ligand were significantly increased compared with the control (P<0.05). This was accompanied by a significant decrease in anti-apoptotic Bcl-2 and Bcl-extra large protein expression compared with the control (P<0.05). Furthermore, BLSA treatment was determined to modulate CNE-1 cell expression of nuclear factor (NF)-κB and NF-κB inhibitor α. The results of the present study indicate that BLSA has anticancer activity through inducing cellular apoptosis. In addition, these results suggest that BLSA can be used as a therapeutic agent in NPC.