IKKα inibition by a glucosamine derivative enhances Maspin expression in osteosarcoma cell line

Split Gp41-1 intein splicing as a model to evaluate the cellular location of the oncosuppressor Maspin in an in vitro model of osteosarcoma

Inteins are proteins involved in the protein splicing mechanism, an autoprocessing event, where sequences (exteins) separated by inteins become ligated each other after recombination. Two kinds of inteins have been described, contiguous inteins and split inteins. The former ones are transcribed and translated as a single peptide along with their exteins, while the latter are fragmented between two different genes and are transcribed and translated separately. The aim of this study is to establish a method to obtain a fluorescent eukaryotic protein to analyze its cellular localization, using the natural split gp41-1 inteins. We chose natural split inteins due to their distribution in all three domains of life. Two constructs were prepared, one containing the N-terminal split intein along with the N-moiety of the Red Fluorescent Protein (RFP) and a second construct containing the C-terminal of split intein, the C-moiety of RFP and the gene coding for Maspin, a tumor suppressor protein. The trans-splicing was verified by transfecting both N-terminal and C-terminal constructs into mammalian cells. The success of the recombination event was highlighted through the fluorescence produced by reconstituted RFP after recombination, along with the overlap of the red fluorescence produced by recombined RFP and the green fluorescence produced by the hybridization of the recombinant Maspin with a specific antibody. In conclusion, we opted to use this mechanism of recombination to obtain a fluorescent Maspin instead to express a large fusion protein, considering that it could interfere with Maspin's structure and function.

IKKβ regulates antimicrobial innate immune responses in the yellow mealworm, Tenebrio molitor

Toll and IMD pathways regulate antimicrobial innate immune responses in insect model systems. The transcriptional activation of antimicrobial peptides (AMPs) confers humoral immunity in the host against invaded pathogens. The IKK kinase complex (IKKα, IKKβ, and the regulatory subunit IKKγ/NEMO) centrally regulates the NF-κB response to various stimuli. It triggers an appropriate antimicrobial immune response in the host. In this study, a TmIKKβ (or TmIrd5) homolog was screened from the RNA-seq database of the coleopteran beetle, Tenebrio molitor. A single exon characterizes the TmIKKβ gene, and the open reading frame (ORF) comprises of 2112 bp that putatively encodes a polypeptide of 703 amino acid residues. TmIKKβ contains a serine/threonine kinase domain and is phylogenetically close to Tribolium castaneum IKKβ homolog (TcIKKβ). TmIKKβ transcripts were highly expressed in the early pupal (P1) and adult (A5) stages. Among the tissues, TmIKKβ showed higher expression in the integument of the last instar larvae and the fat body and hemocytes of 5-day-old adults. TmIKKβ mRNA was upregulated post-E. coli challenge to the host. Moreover, RNAi-based TmIKKβ mRNA silencing increased host larvae' susceptibility against E. coli, S. aureus and C. albicans. TmIKKβ RNAi in the fat body led to a downregulation in mRNA expression of ten out of fourteen AMP genes, including TmTenecin1, -2, and -4; TmDefensin, and -like; TmColeoptericinA, and -B; and TmAttacin1a, -1b, and -2, suggesting the requirement of the gene in antimicrobial innate immune responses. Further, a decrease in the mRNA expression of NF-κB factors such as TmRelish, TmDorsal1, and TmDorsal2 in the fat body of T. molitor larvae was observed post-microorganisms challenge. Thus, TmIKKβ regulates antimicrobial innate immune responses in T. molitor.

Characterizing Hydropathy of Amino Acid Side Chain in a Protein Environment by Investigating the Structural Changes of Water Molecules Network

Assessing the hydropathy properties of molecules, like proteins and chemical compounds, has a crucial role in many fields of computational biology, such as drug design, biomolecular interaction, and folding prediction. Over the past decades, many descriptors were devised to evaluate the hydrophobicity of side chains. In this field, recently we likewise have developed a computational method, based on molecular dynamics data, for the investigation of the hydrophilicity and hydrophobicity features of the 20 natural amino acids, analyzing the changes occurring in the hydrogen bond network of water molecules surrounding each given compound. The local environment of each residue is complex and depends on the chemical nature of the side chain and the location in the protein. Here, we characterize the solvation properties of each amino acid side chain in the protein environment by considering its spatial reorganization in the protein local structure, so that the computational evaluation of differences in terms of hydropathy profiles in different structural and dynamical conditions can be brought to bear. A set of atomistic molecular dynamics simulations have been used to characterize the dynamic hydrogen bond network at the interface between protein and solvent, from which we map out the local hydrophobicity and hydrophilicity of amino acid residues.

TGF-β/PI3K/AKT/mTOR/NF-kB pathway. Clinicopathological features in prostate cancer

Prostate cancer is one of the most common cancers in the male population. The objective of this investigation was to study the relationship of components of transforming growth factor-B (TGF-β)/phosphoinositide-3-kinases (PI3K)/AKT/mammalian target of rapamycin (mTOR)/nuclear factor kappa B (NF-kB) transduction pathway with clinical-pathological markers. By immunohistochemical methods, we determined the expression of several factors [TGF-β, Transforming Growth Factor B Receptor I (TGFBRI), TGFBRII, PI3K, AKT-Ser, AKT-Thr, mTOR, p-mTOR, inhibitor kB kinase (IKK), pIKK, inhibitor kB (IkB), pIkB, NF-kBp50, and NF-kBp65]. To know their relationship with established classical markers (Preoperative serum prostate specific antigen, pathological tumor stage, clinical tumor stage, Gleason score, perineural invasion, node involvement, positive surgical margins, biochemical progression, and survival) and their importance in the prognosis of biochemical progression, Spearman test, survival analysis, Log-rang test, Kaplan-Meier curves, univariate and multivariate Cox proportional Hazard regression analyses were performed. Spearman analysis showed that there was at least one correlation between TGF-β, TGFBRI, PI3K, pAKT-Thr, p-mTOR, NF-kBp50, and classical markers. Cox multivariate analysis between the prognostic variables (pathological tumor stage, Gleason score, and node involvement) and inmunohistochemical parameters confirmed TGFBR1 and PI3K as a prognostic and independent marker of biochemical progression in prostate cancer. Our results suggest that TGFBR1 and PI3K could be used as useful biomarkers for early diagnosis and prognoses for biochemical recurrence in prostate cancer after radical prostatectomy.

IKKγ/NEMO Is Required to Confer Antimicrobial Innate Immune Responses in the Yellow Mealworm, Tenebrio Molitor

IKKγ/NEMO is the regulatory subunit of the IκB kinase (IKK) complex, which regulates the NF-κB signaling pathway. Within the IKK complex, IKKγ/NEMO is the non-catalytic subunit, whereas IKKα and IKKβ are the structurally related catalytic subunits. In this study, TmIKKγ was screened from the Tenebrio molitor RNA-Seq database and functionally characterized using RNAi screening for its role in regulating T. molitor antimicrobial peptide (AMP) genes after microbial challenges. The TmIKKγ transcript is 1521 bp that putatively encodes a polypeptide of 506 amino acid residues. TmIKKγ contains a NF-κB essential modulator (NEMO) and a leucine zipper domain of coiled coil region 2 (LZCC2). A phylogenetic analysis confirmed its homology to the red flour beetle, Tribolium castaneum IKKγ (TcIKKγ). The expression of TmIKKγ mRNA showed that it might function in diverse tissues of the insect, with a higher expression in the hemocytes and the fat body of the late-instar larvae. TmIKKγ mRNA expression was induced by Escherichia coli, Staphylococcus aureus, and Candida albicans challenges in the whole larvae and in tissues such as the hemocytes, gut and fat body. The knockdown of TmIKKγ mRNA significantly reduced the survival of the larvae after microbial challenges. Furthermore, we investigated the tissue-specific induction patterns of fourteen T. molitor AMP genes in TmIKKγ mRNA-silenced individuals after microbial challenges. In general, the mRNA expression of TmTenecin1, -2, and -4; TmDefensin1 and -2; TmColeoptericin1 and 2; and TmAttacin1a, 1b, and 2 were found to be downregulated in the hemocytes, gut, and fat body tissues in the TmIKKγ-silenced individuals after microbial challenges. Under similar conditions, TmRelish (NF-κB transcription factor) mRNA was also found to be downregulated. Thus, TmIKKγ is an important factor in the antimicrobial innate immune response of T. molitor.

A Review of the Effect of a Nanostructured Thin Film Formed by Titanium Carbide and Titanium Oxides Clustered around Carbon in Graphitic Form on Osseointegration

Improving the biocompatibility of implants is an extremely important step towards improving their quality. In this review, we recount the technological and biological process for coating implants with thin films enriched in titanium carbide (TiC), which provide improved cell growth and osseointegration. At first, we discuss the use of a Pulsed Laser Ablation Deposition, which produced films with a good biocompatibility, cellular stimulation and osseointegration. We then describe how Ion Plating Plasma Assisted technology could be used to produce a nanostructured layer composed by graphitic carbon, whose biocompatibility is enhanced by titanium oxides and titanium carbide. In both cases, the nanostructured coating was compact and strongly bound to the bulk titanium, thus particularly useful to protect implants from the harsh oxidizing environment of biological tissues. The morphology and chemistry of the nanostructured coating were particularly desirable for osteoblasts, resulting in improved proliferation and differentiation. The cellular adhesion to the TiC-coated substrates was much stronger than to uncoated surfaces, and the number of philopodia and lamellipodia developed by the cells grown on the TiC-coated samples was higher. Finally, tests performed on rabbits confirmed in vivo that the osseointegration process of the TiC-coated implants is more efficient than that of uncoated titanium implants.

Maspin suppresses cell invasion and migration in gastric cancer through inhibiting EMT and angiogenesis via ITGB1/FAK pathway

This study aims to investigate how Maspin affects the EMT and angiogenesis of gastric cancer (GC) cells via ITGB1/FAK pathway. Immunohistochemistry was used to evaluate the expressions of Maspin, ITGB1, FAK, E-cadherin, Vimentin, D2-40, and CD34 in GC and adjacent normal tissues from 160 patients. Then, the human GC cells with different degree of differentiation were transfected with Maspin CRISPR activation plasmid, ITGB1 siRNA and/or Maspin siRNA, followed by the following experiments, including qRT-PCR, western blotting, tube formation assay, Transwell assay and wound healing. GC tumor tissues manifested decreased Maspin with the activated ITGB1/FAK pathway. In tumor tissues, Maspin was negatively correlated with the expressions of ITGB1 and FAK, as well as Lauren's classification, differentiation degree, and TNM stage. Besides, Maspin was negatively related with lymphatic vessel density (LVD) and microvessel density (MVD), Vimentin and VEGF, but was positive correlated with E-cadherin. Maspin expression decreased, but ITGB1 and p-FAK expressions increased gradually in MKN-28 (well differentiated), SGC-7901 (moderate differentiated), and MKN-45 (poorly differentiated). Maspin CRISPR and ITGB1 siRNA increased E-cadherin with the decreased Vimentin, VEGF and bFGF, and the reductions of tube length. In comparison with the ITGB1 siRNA group, cells in the Maspin siRNA + ITGB1 siRNA group presented the more evident EMT and angiogenesis. Furthermore, ITGB1 siRNA reduced the malignancies of GC cells, which could be restored by Maspin siRNA. Maspin was downregulated in GC tissues, which could inhibit the EMT and angiogenesis by blocking the ITGB1/FAK pathway, thereby decreasing cell invasion and migration of GC.

The potential function of IKKα in gastric precancerous lesion via mediating Maspin

OBJECTIVE

To know the potential role of IKKα (an NF-κB noncanonical pathway) in gastric precancerous lesion via mediating Maspin.

METHODS

Gastric cancer, precancerous lesion and control tissues (chronic non-atrophic gastritis) were collected for determining the expression of IKKα and Maspin by immunohistochemistry. Thereafter, gastric precancerous models were established and divided into the Control group, Model group and Model + shIKKα group. All rats were subjected to observe the pathological changes and ultramicro structure of the gastric mucosa by HE staining or electron microscope, and to measure the serum levels of inflammatory cytokines by ELISA, the expression of apoptosis-related proteins by immunohistochemistry, as well as the expression of IKKα and Maspin by quantitative real-time PCR and Western blotting.

RESULTS

Precancerous lesion and gastric cancer tissues manifested significant upregulation of IKKα positive expression, concomitant with downregulation of the positive expression of Maspin, and these changes were more evident in the gastric cancer tissues. In comparison with the Control group, rats in the Model group had significant increases in serum levels of TNF-α, IL-1β, IL-6 and COX-2, with up-regulations of Bcl-2, CyclinD1, IKKα and p-IKKα, and down-regulations of Bax, Caspase-3 and Maspin. shIKKα treatment attenuate inflammation and apoptosis in gastric precancerous lesion (GPL) rat, with the downregulation of IKKα and p-IKKα, and upregulation of Maspin.

CONCLUSION

Inhibiting IKKα, via upregulating Maspin, can mitigate the inflammation and promote cell apoptosis in precancerous rats, thereby delaying the development of the precancerous lesions.

Correlation analysis based on the hydropathy properties of non-steroidal anti-inflammatory drugs in solid-phase extraction (SPE) and reversed-phase high performance liquid chromatography (HPLC) with photodiode array detection and their applications to biological samples

In the present work we analyzed the hydrophobicity and hydrophilicity properties of several non-steroidal anti-inflammatory drugs (NSAIDs) by investigating the structural changes of the dynamic hydrogen bond network in order to predict the extraction recovery of NSAIDs from biological fluids set by solid phase extraction (SPE). This work allows investigating the relationship between theoretical descriptors and experimental data using a parameter free method with a strong correlation (Pearson correlation 0.95, p-value 0.0003). The identification and quantification of analytes in human plasma were carried out by high performance liquid chromatography coupled with photodiode array detection (HPLC-PDA) using a Kinetex Evo C₁₈ (150 x 4.6 mm I.D) protected by a guard column and a mixture of acetonitrile and 10 mM phosphate buffer (pH 2.5) (50:50, v/v) as mobile phase at isocratic conditions. Accuracy (BIAS%) ranged within -2.33% and + 8.05% while precision (RSD%) was less than 5.73%.The mean extraction recovery of the carprofen (IS) was 84.1% and the recovery of NSAIDs from human plasma ranged between 81.9% to 86.6%. LODs and LOQs for all the investigated NSAIDs were 0.003 and 0.01 μg/mL, respectively. The method was validated according to the ICH guide line in the range 0.010-20.0 μg/mL.

Role of mammary serine protease inhibitor on the inflammatory response in oral lichen planus

OBJECTIVES

Oral lichen planus (OLP) is a chronic inflammatory condition with an unclear pathological mechanism. IκB kinase α (IKKα)-regulated mammary serine protease inhibitor (MASPIN) has been shown to mediate inflammation, particularly in cancers. Here, we explored the expression of MASPIN in OLP and its role in the inflammatory response.

MATERIALS AND METHODS

Immunohistochemistry staining and reverse transcription-polymerase chain reaction assays were used to detect the subcellular localization and expression of MASPIN and IKKα in OLP and healthy control tissues. Levels of the inflammatory factors were compared with enzyme-linked immunosorbent assays. MASPIN and IKKα were overexpressed and silenced, respectively, in an inflammation model of human oral keratinocytes (HOKs) stimulated with lipopolysaccharide (LPS).

RESULTS

Mammary serine protease inhibitor expression was down-regulated, whereas IKKα expression was up-regulated in OLP tissues (p < 0.01). The levels of tumour necrosis factor-alpha and interleukin-6 in OLP tissues were increased compared to those of healthy controls (p < 0.01). MASPIN overexpression in LPS-stimulated HOK cells inhibited the levels of IKKα and the secretion of inflammatory cytokines. By contrast, IKKα silencing promoted the expression of MASPIN and inhibited the secretion of inflammatory cytokines.

CONCLUSION

Both MASPIN and IKKα are involved in the inflammatory process of OLP, suggesting potential therapeutic targets.

Inhibitory-κB Kinase (IKK) α and Nuclear Factor-κB (NFκB)-Inducing Kinase (NIK) as Anti-Cancer Drug Targets

The cellular kinases inhibitory-κB kinase (IKK) α and Nuclear Factor-κB (NF-κB)-inducing kinase (NIK) are well recognised as key central regulators and drivers of the non-canonical NF-κB cascade and as such dictate the initiation and development of defined transcriptional responses associated with the liberation of p52-RelB and p52-p52 NF-κB dimer complexes. Whilst these kinases and downstream NF-κB complexes transduce pro-inflammatory and growth stimulating signals that contribute to major cellular processes, they also play a key role in the pathogenesis of a number of inflammatory-based conditions and diverse cancer types, which for the latter may be a result of background mutational status. IKKα and NIK, therefore, represent attractive targets for pharmacological intervention. Here, specifically in the cancer setting, we reflect on the potential pathophysiological role(s) of each of these kinases, their associated downstream signalling outcomes and the stimulatory and mutational mechanisms leading to their increased activation. We also consider the downstream coordination of transcriptional events and phenotypic outcomes illustrative of key cancer 'Hallmarks' that are now increasingly perceived to be due to the coordinated recruitment of both NF-κB-dependent as well as NF-κB⁻independent signalling. Furthermore, as these kinases regulate the transition from hormone-dependent to hormone-independent growth in defined tumour subsets, potential tumour reactivation and major cytokine and chemokine species that may have significant bearing upon tumour-stromal communication and tumour microenvironment it reiterates their potential to be drug targets. Therefore, with the emergence of small molecule kinase inhibitors targeting each of these kinases, we consider medicinal chemistry efforts to date and those evolving that may contribute to the development of viable pharmacological intervention strategies to target a variety of tumour types.

Targeting IκappaB kinases for cancer therapy

The inhibitory kappa B kinases (IKKs) and IKK related kinases are crucial regulators of the pro-inflammatory transcription factor, nuclear factor kappa B (NF-κB). The dysregulation in the activities of these kinases has been reported in several cancer types. These kinases are known to regulate survival, proliferation, invasion, angiogenesis, and metastasis of cancer cells. Thus, IKK and IKK related kinases have emerged as an attractive target for the development of cancer therapeutics. Several IKK inhibitors have been developed, few of which have advanced to the clinic. These inhibitors target IKK either directly or indirectly by modulating the activities of other signaling molecules. Some inhibitors suppress IKK activity by disrupting the protein-protein interaction in the IKK complex. The inhibition of IKK has also been shown to enhance the efficacy of conventional chemotherapeutic agents. Because IKK and NF-κB are the key components of innate immunity, suppressing IKK is associated with the risk of immune suppression. Furthermore, IKK inhibitors may hit other signaling molecules and thus may produce off-target effects. Recent studies suggest that multiple cytoplasmic and nuclear proteins distinct from NF-κB and inhibitory κB are also substrates of IKK. In this review, we discuss the utility of IKK inhibitors for cancer therapy. The limitations associated with the intervention of IKK are also discussed.

Molecular mechanisms of anticancer effects of Glucosamine

Glucosamine is an amino sugar that is produced naturally in human body. It is an essential carbohydrate component of many cellular glycoproteins, glycolipids, and glycosaminoglycans (GAGs). This popular over-the-counter supplement is also found in the exoskeleton of crustaceans. Glucosamine and its derivatives have a long history in medicine for inflammatory conditions specially to relieve arthritis. This dietary supplement has numerous biological and pharmacological properties, including anti-inflammatory, antioxidant, anti-aging, anti-fibrotic, neuroprotective and cardioprotective activities. Many studies have shown that glucosamine has anti-cancer activity through influence on biological pathways involved in cell death, apoptosis, cell proliferation, and angiogenesis. Accordingly, this comprehensive review summarizes anti-cancer molecular mechanisms of glucosamine in details.

SPOCK1 promotes the growth of Osteosarcoma cells through mTOR-S6K signaling pathway

SPOCK1 belongs to the SPARC family, which plays an important role in proliferation, invasion and migration of various tumour cells. However, the functions of SPOCK1 in osteosarcoma cell growth and proliferation have not been fully elucidated. In the present study, we found that SPOCK1 is significantly upregulated in osteosarcoma tissue. Moreover, overexpression of SPOCK1 was associated with tumour size, metastasis, Enneking stage and pathological degree. Furthermore, knockdown of SPOCK1 expression suppressed the growth of osteosarcoma cells in vitro and reduced tumourigenicity in nude mice in vivo. Additionally, our data suggest that inactivation of the mTOR-S6K signaling pathway participated in inhibition of SPOCK1-mediated suppression of osteosarcoma cell growth. These findings represent a novel pathogenetic mechanism of osteosarcoma development that provides a potential target for therapeutic strategies for osteosarcoma.

Inhibitory Kappa B Kinase α (IKKα) Inhibitors That Recapitulate Their Selectivity in Cells against Isoform-Related Biomarkers

IKKβ plays a central role in the canonical NF-kB pathway, which has been extensively characterized. The role of IKKα in the noncanonical NF-kB pathway, and indeed in the canonical pathway as a complex with IKKβ, is less well understood. One major reason for this is the absence of chemical tools designed as selective inhibitors for IKKα over IKKβ. Herein, we report for the first time a series of novel, potent, and selective inhibitors of IKKα. We demonstrate effective target engagement and selectivity with IKKα in U2OS cells through inhibition of IKKα-driven p100 phosphorylation in the noncanonical NF-kB pathway without affecting IKKβ-dependent IKappa-Bα loss in the canonical pathway. These compounds represent the first chemical tools that can be used to further characterize the role of IKKα in cellular signaling, to dissect this from IKKβ and to validate it in its own right as a target in inflammatory diseases.