The Enhanced Cytotoxic Effects in B-Cell Leukemia and Lymphoma Following Activation of Prostaglandin EP4 Receptor and Targeting of CD20 Antigen by Monoclonal Antibodies.

Anti-CD20 monoclonal antibodies (MAbs) have revolutionized the treatment of B-cell leukemia and lymphoma. However, many patients do not respond to such treatment due to either deficiency of the complementary immune response or resistance to apoptosis. Other currently available treatments are often inadequate or induce major side effects. Therefore, there is a constant need for improved therapies. The prostaglandin E2 receptor 4 (EP4) receptor has been identified as a promising therapeutic target for hematologic B-cell malignancies. Herein, we report that EP4 receptor agonists PgE1-OH and L-902688 have exhibited enhanced cytotoxicity when applied together with anti-CD20 MAbs rituximab, ofatumumab and obinutuzumab in vitro in Burkitt lymphoma cells Ramos, as well as in p53-deficient chronic lymphocytic leukemia (CLL) cells MEC-1. Moreover, the enhanced cytotoxic effects of EP4 receptor agonists and MAbs targeting CD20 have been identified ex vivo on primary lymphocytes B obtained from patients diagnosed with CLL. Incubation of cells with PgE1-OH and L-902688 preserved the expression of CD20 molecules, further confirming the anti-leukemic potential of EP4 receptor agonists in combination with anti-CD20 MAbs. Additionally, we demonstrated that the EP4 receptor agonist PgE-1-OH induced apoptosis and inhibited proliferation via the EP4 receptor triggering in CLL. This work has revealed very important findings leading towards the elucidation of the anticancer potential of PgE1-OH and L-902688, either alone or in combination with MAbs. This may contribute to the development of potential therapeutic alternatives for patients with B-cell malignancies.

Search for new biologically active compounds: in vitro studies of antitumor and antimicrobial activity of dirhodium(II,II) paddlewheel complexes.

Four neutral Rh1-Rh4 complexes of the general formula [Rh2(CH3COO)4L2], where L is an N-alkylimidazole ligand, were synthesized and characterized using various spectroscopic techniques, and in the case of Rh4 the crystal structure was confirmed. Investigation of the interactions of these complexes with HSA by fluorescence spectroscopy revealed that the binding constants Kb are moderately strong (∼104 M-1), and site-marker competition experiments showed that the complexes bind to Heme site III (subdomain IB). Competitive binding studies for CT DNA using EB and HOE showed that the complexes bind to the minor groove, which was also confirmed by viscosity experiments. Molecular docking confirmed the experimental data for HSA and CT DNA. Antimicrobial tests showed that the Rh2-Rh4 complexes exerted a strong inhibitory effect on G+ bacteria B. cereus and G- bacteria V. parahaemolyticus as well as on the yeast C. tropicalis, which showed a higher sensitivity compared to fluconazole. The cytotoxic activity of Rh1-Rh4 complexes tested on three cancer cell lines (HeLa, HCT116 and MDA-MB-231) and on healthy MRC-5 cells showed that all investigated complexes elicited more efficient cytotoxicity on all tested tumor cells than on control cells. Investigation of the mechanism of action revealed that the Rh1-Rh4 complexes inhibit cell proliferation via different mechanisms of action, namely apoptosis (increase in expression of the pro-apoptotic Bax protein and caspase-3 protein in HeLa and HCT116 cells; changes in mitochondrial potential and mitochondrial damage; release of cytochrome c from the mitochondria; cell cycle arrest in G2/M phase in both HeLa and HCT116 cells together with a decrease in the expression of cyclin A and cyclin B) and autophagy (reduction in the expression of the protein p62 in HeLa and HCT116 cells).

The Westermo network traffic data set.

There is a growing body of knowledge on network intrusion detection, and several open data sets with network traffic and cyber-security threats have been released in the past decades. However, many data sets have aged, were not collected in a contemporary industrial communication system, or do not easily support research focusing on distributed anomaly detection. This paper presents the Westermo network traffic data set, 1.8 million network packets recorded in over 90 minutes in a network built up of twelve hardware devices. In addition to the raw data in PCAP format, the data set also contains pre-processed data in the form of network flows in CSV files. This data set can support the research community for topics such as intrusion detection, anomaly detection, misconfiguration detection, distributed or federated artificial intelligence, and attack classification. In particular, we aim to use the data set to continue work on resource-constrained distributed artificial intelligence in edge devices. The data set contains six types of events: harmless SSH, bad SSH, misconfigured IP address, duplicated IP address, port scan, and man in the middle attack.

EP4 receptor agonist L-902688 augments cytotoxic activities of ibrutinib, idelalisib, and venetoclax against chronic lymphocytic leukemia cells.

Treatment of patients with relapsed or refractory chronic lymphocytic leukemia (CLL) has significantly improved more recently with the approval of several new agents, including ibrutinib, idelalisib, and venetoclax. Despite the outstanding efficacies observed with these agents, these treatments are sometimes discontinued due to toxicity, unresponsiveness, transformation of the disease and/or resistance. Constitutive NF-κB activation that protects CLL cells from apoptotic stimuli represents one of molecular mechanisms that underlie the emergence of drug resistance. As prostaglandin E (EP)4 receptor agonists have been shown to successfully inhibit the NF-κB pathway in B-cell lymphoma cells, we investigated the potential of the highly specific EP4 receptor agonist L-902688 for the potential treatment of patients with CLL. We show here that low micromolar concentrations of L-902688 can indeed induce selective cytotoxicity towards several B-cell malignancies, including CLL. Moreover, L-902688-mediated activation of the EP4 receptor in patient derived CLL cells resulted in inhibition of the NF-κB pathway, cell proliferation, and induction of apoptosis. Most importantly, we show for the first time that in combination with ibrutinib, idelalisib, or venetoclax, L-902688 induces synergistic cytotoxic activity against patient derived CLL cells. To conclude, the modulation of NF-κB activity by EP4 receptor agonists represents an innovative approach to improve the treatment of patients with CLL. In particular, EP4 receptor agonists appear to represent promising adjuncts to the already existing therapies for patients with CLL due to these promising synergistic activities.

Draft Genome Sequence of Actinomyces neuii UMB1295, Isolated from the Female Urinary Tract.

Actinomyces neuii is an opportunistic pathogen. Within the urogenital tract, it has been associated with bacterial vaginosis and overactive bladder symptoms. Here, we investigate a draft genome sequence of A. neuii UMB1295, which was isolated from a catheterized urine sample from a woman with a urinary tract infection.

Endocrine disrupting activities and immunomodulatory effects in lymphoblastoid cell lines of diclofenac, 4-hydroxydiclofenac and paracetamol.

A critical literature review reveals that knowledge of side effects of pharmaceuticals diclofenac and paracetamol is extremely important because of their widespread use and occurrence in the environment. In order to delineate whether these compounds have endocrine activity and influence on the immune system, we assessed the potential endocrine disrupting and immunomodulatory activities of: diclofenac (DIC), its metabolite 4-hydroxydiclofenac (4-HD) and paracetamol (PAR). Herein, we report on their impact on estrogen receptor (ER), androgen receptor (AR), glucocorticoid receptor (GR) and thyroid hormone receptor (TR). The endocrine disrupting effects were assessed in vitro in MDA-kb2 and GH3.TRE-Luc cell lines and by the XenoScreen YES/YAS assay. Moreover, binding affinity to nuclear receptors (GR and AR) was also measured. Immunomodulatory properties of the compounds were evaluated in lymphoblastoid cell lines. All the tested compounds showed endocrine disrupting and immunomodulatory activities. The results revealed that both DIC and its metabolite 4-HD exhibited significant estrogenic, anti-androgenic (in YAS assay), (anti)-androgenic, (anti)-glucocorticoid and anti-thyroid hormonal activities (in luciferase reporter gene assays). DIC showed direct binding to the GR, while its metabolite 4-HD to the GR and AR. Only metabolite 4-HD showed estrogenic, androgenic (in YAS assay) and thyroid-hormonal activities. PAR had anti-androgenic activity and anti-thyroid hormonal activity. PAR displayed GR agonist activity with competition to its receptor and agonistic activity to AR. All of the compounds significantly modulated pro-inflammatory and immunoregulatory cytokine production in lymphoblastoid cell lines and were thus proven immunomodulatory. The study is useful in determining toxicological effects and contributes to the knowledge of possible side effects of diclofenac, its metabolite and paracetamol.

Structural features of subtype-selective EP receptor modulators.

Prostaglandin E2 is a potent endogenous molecule that binds to four different G-protein-coupled receptors: EP1-4. Each of these receptors is a valuable drug target, with distinct tissue localisation and signalling pathways. We review the structural features of EP modulators required for subtype-selective activity, as well as the structural requirements for improved pharmacokinetic parameters. Novel EP receptor subtype selective agonists and antagonists appear to be valuable drug candidates in the therapy of many pathophysiological states, including ulcerative colitis, glaucoma, bone healing, B cell lymphoma, neurological diseases, among others, which have been studied in vitro, in vivo and in early phase clinical trials.

Characterization of human lymphoblastoid cell lines as a novel in vitro test system to predict the immunotoxicity of xenobiotics.

Evaluating immunomodulatory effects of xenobiotics is an important component of the toxicity studies. Herein we report on the establishment of a novel invitro test system for the immunotoxicity screening of xenobiotics based on human lymphoblastoid cell lines (LCLs). Four immunotoxic compounds; tributyltin chloride, cyclosporine A, benzo(a)pyrene and verapamil hydrochloride, as well as three immune-inert compounds; urethane, furosemide and mannitol were selected for characterization. The treatment of LCLs with immunosuppressive compounds resulted in reduced viability. The IC50 values determined in human LCLs were in agreement with the data obtained for human peripheral mononuclear cells. Since cytokine production reflects lymphocytes responses to external stimuli, we evaluated the functional responses of LCLs by monitoring their pro-inflammatory and immunoregulatory cytokine production. Our findings prove that LCLs allowed for reliable differentiation between immunomodulatory and immune-inert compounds. Hence, pre-treatment with immunomodulatory compounds led to a decrease in the production of pro-inflammatory TNFα, IL-6 and immunoregulatory IL-2, IL-4, IL-10 and IFNγ cytokines, when compared to untreated ionomycin/PMA stimulated cells. Moreover, testing a panel of ten LCLs derived from unrelated healthy individuals reflects inter-individual variability in response to immunomodulatory xenobiotics. In conclusion, LCLs provide a novel alternative method for the testing of the immunotoxic effects of xenobiotics.

Antioxidant and anti-inflammatory properties of 1,2,4-oxadiazole analogs of resveratrol.

The chemopreventive properties of resveratrol are ascribed mostly to its antioxidant activity, in particular its scavenging ability for reactive oxygen species (ROS), and to the inhibition of NF-κB pathway which has also been suggested as an important underlying mechanism of its reported properties. In present study, a small library of nine 1,2,4-oxadiazole-based structural analogs of resveratrol were assayed for their antioxidant and anti-inflammatory activities. Several compounds showed significant inhibitory activities against NF-κB and/or ROS production. Compound 2, incorporating two para-hydroxyphenyl moieties connected by the 1,2,4-oxadiazole ring, was the most active, its potency in inhibiting activation of NF-κB and ROS scavenging abilities surpassing that of resveratrol. Additionally, we elucidated the mechanisms underlying the NF-κB inhibitory activity of compound 2. Finally, in contrast to resveratrol, compound 2 significantly reduced the LPS-induced release of pro-inflammatory cytokines, indicating its prominent anti-inflammatory potential.

Chemo-sensitizing effects of EP4 receptor-induced inactivation of nuclear factor-κB.

The EP4 receptor conveys growth-inhibitory effects in mature and immature B cells via NF-κB. Herein, the EP4 receptor was evaluated as a potential therapeutic target for leukemia and lymphoma, whose survival depends on the constitutive activity of NF-κB. Utilizing a pharmacological approach, we proved that the EP4 receptor induces caspase-mediated apoptosis in malignantly transformed B cells, with the most prominent effect being on Burkitt׳s lymphoma cells. Since the increased activation of NF-κB underlies multi-drug resistance phenomena, we modulated this signaling pathway via EP4 receptor triggering. Pge1-OH, a specific EP4 receptor agonist, led to decreased NF-κB activity and a consequent decrease in levels of the antiapoptotic gene Bcl-xL in Ramos cells, resulting in an elevated sensitivity of cells towards bortezomib- and doxorubicin-induced chemotherapeutic effects. Our study identifies the as yet unrecognized potential of EP4 receptor agonists as chemo-sensitizing agents in B-cell lymphoma. The specific downregulation of NF-κB-dependent pathways in B-cell malignancies opens new possibilities for treatment and current therapy optimization using specific EP4 receptor agonists.