Differential Cytotoxic Activity Research Articles

Abstract 2029: Investigation of anti-tumor activity of porcine myeloperoxidase for urothelial carcinoma of the bladder

Abstract Introduction: Porcine myeloperoxidase (pMPO) is a cationic enzyme secreted by granulocytic leukocytes capable of selectively binding cancer cells due to their negative surface charge. In the presence of hydrogen peroxide (H2O2) and sodium chloride (NaCl), MPO catalyzes the production of electronically excited singlet molecular oxygen, which exerts focused cytotoxic activity against cancer cells. Methods: Human bladder non-cancer (SV-HUC1) and cancer cells (T24 and 5637) were used to assess differential cytotoxic activity of pMPO. pMPO was combined with associated reagents, including H2O2, NaCl, and L-proline and glycine for 45 minutes to support the generation of singlet oxygen. MTS assay was used to assessed cell viability at day 3 post-treatment. Non-cancer and cancer cells were labeled with GFP and mCherry, respectively, via infection with lentivirus and cultured in tandem to allow for simultaneous treatment of both cell types. After the treatment, flow cytometry and microscopy were used to monitor the growth of the cells. Results: No cytotoxicity was noted when SV-HUC1 cells were cultured with individual reagents pMPO, NaCl, L-Proline, or Glycine, and limited cytotoxicity was observed with H2O2. Notably, cell viability was nearly maximally preserved for SV-HUC1 cells. The combination of pMPO with associated reagents resulted in killing of 5637 and T24 cells, with tumoricidal activity maintained across increasing tumor cell density, with cell viability preserved for SV-HUC1 cells. Within the cell co-culture system, simultaneous treatment of both cell types with the pMPO treatment resulted in selective killing of tumor cells and preservation of SV-HUC1 cells. Mechanistic studies confirm specificity of pMPO binding to tumor cells, and further, high levels of expression of gammaH2AX and phospho-ATM in 5637 and T24 cells following treatment. Conclusion: pMPO demonstrates selective and efficient killing of bladder cancer cells with minimal cytotoxicity against non-cancer urothelial cells. Given its reliance on direct surface contact with tumor cells for activity, pMPO may be developed as an intravesical therapy for treatment of non-muscle invasive bladder cancers. Acknowledgements: This work was partially supported by Mayo funds provided to Dr. Haojie Huang. Citation Format: Junnan Liu, Robert C. Allen, Jackson T. Stephens, Paras Shah, Haojie Huang. Investigation of anti-tumor activity of porcine myeloperoxidase for urothelial carcinoma of the bladder [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2029.

Synthesis, structural study and antitumor activity of novel alditol-based imidazophenanthrolines (aldo-IPs)

A series of 1H-imidazo [4,5-f][1,10] phenanthroline derivatives functionalized at 2-position with chiral, and conformationally flexible polyhydroxy alkyl chains derived from carbohydrates (alditol-based imidazophenanthrolines, aldo-IPs) is presented herein. These novel glycomimetics showed relevant and differential cytotoxic activity against several cultured tumor cell lines (PC3, HeLa and HT-29), dependent on the nature and stereochemistry of the polyhydroxy alkyl chain. The mannose-based aldo-IP demonstrated the higher cytotoxicity in the series, substantially better than cisplatin metallo-drug in all cell lines tested, and better than G-quadruplex ligand 360A in HeLa and HT29 cells. Cell cycle experiments and Annexin V-PI assays revealed that aldo-IPs induce apoptosis in HeLa cells. Initial study of DNA interactions by DNA FRET melting assays proved that the aldo-IPs produce only a slight thermal stabilization of DNA secondary structures, more pronounced in the case of quadruplex DNA. Viscosity titrations with CT dsDNA suggest that the compounds behave as DNA groove binders, whereas equilibrium dialysis assays showed that the compounds bind CT with Ka values in the range 104–105 M−1. The aldo-IP derivatives were obtained with synthetically useful yields through a feasible one-pot multistep process, by aerobic oxidative cyclization of 1,10‐phenanthroline‐5,6‐diamine with a selection of unprotected aldoses using (NH4)2SO4 as promoter.

PD17-10 DISCOVERY OF A NOVEL MONOCLONAL PD-L1 ANTIBODY H1A THAT PROMOTES T-CELL MEDIATED TUMOR KILLING ACTIVITY IN RENAL CELL CARCINOMA

You have accessJournal of UrologyCME1 Apr 2023PD17-10 DISCOVERY OF A NOVEL MONOCLONAL PD-L1 ANTIBODY H1A THAT PROMOTES T-CELL MEDIATED TUMOR KILLING ACTIVITY IN RENAL CELL CARCINOMA Reza Nabavizadeh, Rodrigo Rodrigues Pessoa, Zesheng An, Joanina Gicobi, Susan Harrington, Henan Zhang, Tianxiao Xu, Jacob Hirdler, Christine Lohse, Bradley Leibovich, Haidong Dong, and Fabrice Lucien Reza NabavizadehReza Nabavizadeh More articles by this author , Rodrigo Rodrigues PessoaRodrigo Rodrigues Pessoa More articles by this author , Zesheng AnZesheng An More articles by this author , Joanina GicobiJoanina Gicobi More articles by this author , Susan HarringtonSusan Harrington More articles by this author , Henan ZhangHenan Zhang More articles by this author , Tianxiao XuTianxiao Xu More articles by this author , Jacob HirdlerJacob Hirdler More articles by this author , Christine LohseChristine Lohse More articles by this author , Bradley LeibovichBradley Leibovich More articles by this author , Haidong DongHaidong Dong More articles by this author , and Fabrice LucienFabrice Lucien More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003272.10AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Immune checkpoint inhibitors (ICI) have shown conflicting outcomes in the adjuvant setting for high-risk clear cell renal cell carcinoma (ccRCC) patients. There is an unmet need to identify patients who would benefit from ICI treatment and to develop new therapies for those who progress on current anti PD1/PD-L1 treatments. Our group has recently created a novel monoclonal antibody (H1A) that induces PD-L1 destabilization at the cell surface resulting in its degradation. In this study, we evaluated the T-cell killing rate in response to current FDA approved treatments as well as H1A. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from 13 subjects 3 months after nephrectomy for ccRCC. For treatment with ICI, antibodies were added at the time of activation with soluble anti-CD3 and at 20 μg/ml concentration. Human 786-O ccRCC cells was used as target cells and killing rates were measured by calcein release assay. Paired ANOVA test was used to compare efficacy of ICI. RESULTS: The median increase in T-cell killing rate for pembrolizumab, nivolumab and atezolizumab were 37.8% (range 17.4%-57.7%), 36.6% (range 6 22.7%-65.4%) and 29.9% (range 10%-52.5%), respectively. Individual response to immune checkpoint inhibitors was heterogeneous with some patients showing stronger response with nivolumab (n=9) while others had better killing activity with pembrolizumab (n=3) and one patient with no difference between different treatments. No best response was observed with atezolizumab across all patients. Median killing rate for H1A was 41.7% (range 25%-71.2%). Overall, median killing rate was significantly higher with H1A compared to the pembrolizumab (p=0.0003) and nivolumab (p=0.003) (Figure 1). In terms of individual response, all H1A-treated patients showed improved tumor cell killing efficiency compared to other treatment groups. CONCLUSIONS: In this proof-of-concept, we showed differential T-cell cytotoxic activity in response to various FDA-approved ICI. Additionally, we demonstrated the therapeutic value of a newly developed PD-L1 monoclonal antibody that induces stronger cytotoxic tumor cell killing from ccRCC patient-derived CD8 T cells compared to other ICI. Source of Funding: This work was supported by NIH R01CA256927 (HD) and R01AI095239 (HD) © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e499 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Reza Nabavizadeh More articles by this author Rodrigo Rodrigues Pessoa More articles by this author Zesheng An More articles by this author Joanina Gicobi More articles by this author Susan Harrington More articles by this author Henan Zhang More articles by this author Tianxiao Xu More articles by this author Jacob Hirdler More articles by this author Christine Lohse More articles by this author Bradley Leibovich More articles by this author Haidong Dong More articles by this author Fabrice Lucien More articles by this author Expand All Advertisement PDF downloadLoading ...

Differential Cytotoxic Activity of a New Cationic Pd(II) Coordination Compound with N4-Tetradentate Hybrid Ligand in Cancer Cell Lines

Objective: Successful cancer treatment still requires the discovery of novel compounds that hold promise for chemotherapeutics. The objective of this study was to examine the effectiveness of a newly synthesized cationic palladium(II) coordination compound that functions via several pathways to provide an efficient therapeutic option for various cancer cells. Materials and Methods: A new cationic palladium(II) coordination compound, [Pd(L)]Cl2·H2O, denoted as Complex 1, where the ligand L is the compound 6,6'-bis(NH-benzimidazol-2-yl)-2,2'-bipyridine), was synthesized and characterized by the attenuated total reflectance (ATR) - fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1 H NMR), electrospray ionization mass spectrometry (ESI-MS), and carbon-hydrogen-nitrogen (CHN) analyses. The density functional theory (DFT) calculations show the coordination sphere around the metal center in Complex 1 to be made up of tertiary N atoms of the pyridine (py) and benzimidazole (bim) rings completing the square-planar geometry with significant distortion. The anti-growth/cytotoxic activity of the complex was determined using the sulforhodamine B (SRB) and adenosine triphosphate (ATP) viability assays for 24 and 48 h in vitro. The study evaluates the determinations for annexin V-propidium iodide (PI) positivity, mitochondrial membrane potential loss, Bcl-2 protein inactivation, and deoxyribonucleic acid (DNA) damage to investigate the cell death mode and its partial mechanism. Results: Complex 1 caused cytotoxicity in a dose-dependent manner in all the cell lines used, with IC50 values ranging from 2.6-8.8 μM for 48 h. Among the cancer models, colon and breast cancer cell lines underwent cell death by well-described apoptosis through the intrinsic pathway involving the mitochondria. However, the other cell lines did not show such a cell death modality. This implies that differential cell death modes operate based on the cancer type. Conclusion: For the treatment of breast and colon cancers, the complex 1 appears to be a unique, promising complex. Therefore, complex 1 deserves further attention for proof of concept in animal models.

Differential cytotoxic activity of pharmacological inhibitors of IGF1R-related pathways in JAK2V617F driven cells

Myeloproliferative neoplasms (MPN) belong to a group of clonal diseases of hematopoietic stem cells characterized by aberrant proliferation of mature myeloid lineages. The constitutive activation of the JAK2/STAT signaling pathway is now well established to play a central role in MPN pathogenesis; however, accumulating evidence now indicates that the IGF1R-mediated signaling pathway contributes to the maintenance of the malignant phenotype. Studies using inhibitors of IGF1-mediated signaling have reported cytotoxic effects in cellular and murine models of MPN, but no consensus has been reached regarding the potency and efficacy of inhibitors of the IGF1R-related pathway in this context. In the present study, we compared the potency and efficacy of three inhibitors of IGF1R-related pathways in a JAK2V617F-driven cellular model. These inhibitors (NT157, OSI-906, and NVP-AEW54) present antineoplastic activity with similar efficacy in Ba/F3 JAK2V617F cells, with NT157 showing the greatest potency. Both the induction of apoptosis and reduction in cell proliferation were associated with the observed reduction in cell viability. Downregulation of JAK2/STAT signaling was an advantageous off-target effect of all three inhibitors. These preclinical studies reinforce the potential of the IGF1R-related pathway as a therapeutic target in MPN.

Highly Active Thermophilic L-Asparaginase from Melioribacter roseus Represents a Novel Large Group of Type II Bacterial L-Asparaginases from Chlorobi-Ignavibacteriae-Bacteroidetes Clade.

L-asparaginase (L-ASNase) is a biotechnologically relevant enzyme for the pharmaceutical, biosensor and food industries. Efforts to discover new promising L-ASNases for different fields of biotechnology have turned this group of enzymes into a growing family with amazing diversity. Here, we report that thermophile Melioribacter roseus from Ignavibacteriae of the Bacteroidetes/Chlorobi group possesses two L-ASNases—bacterial type II (MrAII) and plant-type (MrAIII). The current study is focused on a novel L-ASNase MrAII that was expressed in Escherichia coli, purified and characterized. The enzyme is optimally active at 70 °C and pH 9.3, with a high L-asparaginase activity of 1530 U/mg and L-glutaminase activity ~19% of the activity compared with L-asparagine. The kinetic parameters KM and Vmax for the enzyme were 1.4 mM and 5573 µM/min, respectively. The change in MrAII activity was not significant in the presence of 10 mM Ni2+, Mg2+ or EDTA, but increased with the addition of Cu2+ and Ca2+ by 56% and 77%, respectively, and was completely inhibited by Zn2+, Fe3+ or urea solutions 2–8 M. MrAII displays differential cytotoxic activity: cancer cell lines K562, Jurkat, LnCap, and SCOV-3 were more sensitive to MrAII treatment, compared with normal cells. MrAII represents the first described enzyme of a large group of uncharacterized counterparts from the Chlorobi-Ignavibacteriae-Bacteroidetes clade.

Design and in Vitro Evaluation of a CAR-T Prototype (ARI-0003) Targeting CD123 for Acute Myeloid Leukemia

IntroductionThe outcome of patients with Acute Myeloid Leukemia (AML) is still dismal, especially in patients with a relapsed or refractory (R/R) disease. In these patients, innovative treatment strategies must be considered in order to improve survival. Chimeric Antigen Receptor T-cell (CART) immunotherapy has demonstrated its efficacy and safety in diverse B-cell neoplasms and therefore is being investigated in other hematological malignancies. In AML, CART development is challenging due to the absence of a universal target antigen across AML subtypes, as well as on-target/off-tumor toxicity in healthy tissues. Among all explored AML antigens, CD123 seems to be a safe antigen to target, given its expresion in a high proportion of bulk and leukemic AML stem cells and with a higher level compared to normal hematopoietic progenitors cells. Herein we detail the generation and the in vitro assays of a CD123 CAR-T model (ARI-0003) for AML.MethodsWe developed an anti-CD123 antibody-secreting hybridoma and thereafter identified the variable domains of heavy and light chains of the immunoglobulin to create the scFv domain. The CAR (ARI-0003) genetic sequence was designed and cloned into a pCCL plasmid, and together with a VSV-G, RRE and REV plasmids we transfected HEK 293T cells to obtain 3 rd generation lentivirus (Figure 1A). T-lymphocytes were obtained from healthy volunteers and were transduced with lentiviral vectors to generate CAR-T cells. CAR expression in infected T-cells was monitored with flow cytometry using anti-F(ab) 2 antibodies. To test in vitro activity against AML, non-transduced T-lymphocytes (NT) and CAR-T cells were incubated with AML cell lines and AML primary samples from diverse genetic subtypes, and cytotoxicity was evaluated by flow cytometry at 24 and 48 hours using CD123 and CD33 antibodies.ResultsAt the time of co-incubation of target cells and lymphocytes, the mean scFv expression of ARI-0003 in CAR-T cells was 37% (range, 20-57). Cytotoxicity assays with AML cell lines (THP-1, Kasumi1) showed higher target cell mortality with CAR-T cells, compared to NT cells (mean percentage of alive cells at 48h, obtained with an effector-target cell ratio of 1:1, of 0 and 1% [CAR] vs 45 and 57 [NT] in THP-1 and Kasumi1, respectively; Figure 1B-C). This differential cytotoxic activity was maintained using distinct effector ratio, being statistically significant in higher ratios (namely, 1:1, 1:2 and 1:4). Moreover, cytotoxicity induced by CAR-T cells was higher at 48 hours compared to 24 hours. To demonstrate antigen specificity of ARI-0003 CAR-T cells, CD123 negative cell lines (Raji, 697) were used, and target cell mortality was not statistically significant between CAR-T and NT in CD123-negative cell lines.Finally, ARI-0003 CAR-T efficacy was tested against 8 primary AML samples with a distinct genetic risk, including 5 unfavorable cases according to the European LeukemiaNet classification and 3 AML samples refractory to multiple high-intensity regimens (Figure 1F). Interestingly, a significant cytotoxic effect was observed against all 8 samples after incubation with ARI-0003 CAR-T cells at higher E:T ratio (p < 0.05 for ratios 1:1, 1:2 and 1:4; Figure D-E).ConclusionsIn vitro assays showed that immunotherapy with CAR-T cells ARI0003 against CD123 could be an effective approach for R/R AML. In vivo experiments are needed in order to confirm these results before translating this therapy to clinical phases. Moreover, on-target/off-tumor toxicity induced by ARI-0003 CAR-T needs to be explored, especially myelotoxicity due to target antigen expression in hematopoietic precursor cells.Figure legendA) Structure of the ARI0003 CAR. B) Cytotoxicity of CAR-T cells against cell lines (normalized to background toxicity observed with NT cells). C) Flow cytometry of THP1 cells against NT and CAR-T cells. D) Cytotoxicity of CAR-T cells against AML primary samples (normalized to NT percentage). E) Absolut number of remaining AML cells after 48h of coincubation with CAR or NT cells. F) Characteristics of AML primary samples used for in vitro assays. [Display omitted] DisclosuresDiaz-Beyá: Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astellas: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jazz: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Esteve: Abbvie: Consultancy; Astellas: Consultancy; Bristol Myers Squibb/Celgene: Consultancy; Novartis: Consultancy, Research Funding; Pfizer: Consultancy; Jazz: Consultancy; Novartis: Research Funding.

Perforin Is Dispensable for Anti-CD19 CAR-T Cell Cytotoxicity but Contributes to CAR-T Cell Contraction and Regulates Host Inflammatory Response

Background: Chimeric antigen receptor transduced T cell (CAR-T) therapy against B-cell malignancies is highly effective, but is frequently associated with cytokine release syndrome (CRS). In severe cases, CRS can be associated with a prolonged life-threatening systemic inflammatory response mimicking manifestations of hemophagocytic lymphohistiocytosis (HLH). Primary HLH occurs among individuals harboring genetic defects in granule-mediated cytotoxicity pathway, such as perforin gene mutations. In a murine primary HLH model, IFNγ derived from antigen-specific CD8+ T cells is implicated as a major mediator of HLH pathology. We explored the role of granule-mediated cytotoxicity and IFNγ in CAR-T response and toxicity, using an established syngeneic murine model of anti-CD19-CAR-T therapy against B-cell malignancy.Methods: Splenic T cells derived from perforin knockout (Prf-/-), wild-type (WT), and IFNγ adenylate-uridylate-rich element-deleted (ARE-/-: a strain with stable IFNγ mRNA transcript) mice on the B6 background were transduced with second-generation murine anti-CD19 CAR (ScFV-CD28-CD3z). In in vivo experiments, mice received cyclophosphamide (200 mg/kg) intraperitoneally 24 hours prior to CAR-T adoptive transfer as lymphodepletion.Results: Both WT and Prf-/- T cells were successfully transduced with a mean transduction efficiency of 80%, and resulted in similar immunophenotypic composition (CD8/CD4, TCM/TEM) at baseline. Compared to WT CAR-T, Prf-/- CAR-T produced a higher amount of IFNγ when co-cultured with CD19+ leukemia (12-hour coculture supernatant IFNγ, WT 7822 pg/mL vs. Prf-/- 14743 pg/mL, p<0.0001). In vitro cytotoxicity assays (Incucyte) demonstrated that Prf-/- CAR-T were less efficient in clearing leukemia compared to WT. The differential cytotoxic activity between WT and Prf-/- CAR-T became apparent in vivo when CAR-T were given at low dosage (1E5, which is a curative dosage for WT CAR-T). However, at higher dosage (1E6 or higher), Prf-/- CAR-T eradicated CD19+ leukemia in vivo with the same leukemia clearance kinetics as WT CAR-T and achieved long-term complete remission. During maximal in vivo CAR-T expansion, mice treated with high-dose Prf-/- CAR-T (7E6) had elevated serum IFNγ level, while IFNγ in WT CAR-T group was barely detectable (Fig. 1). Such an increase in IFNγ serum levels did not occur at the lower cell dosage (1E5) in either Prf-/- or WT CAR-T group. Maximal in vivo CAR-T expansion occurred between day 3-4 in both WT and Prf-/- groups. With WT cells, CAR-T contracted by day 8 as leukemia cleared (Fig. 2), and the surface CAR expression dropped and CAR-T phenotype transitioned from TEM to TCM. Surprisingly, Prf-/- CAR-T had a secondary proliferation between day 13-20 (Fig. 2) despite no measurable leukemia or endogenous B-cells at that time. Prf-/- CAR-T had a sustained high level of surface CAR expression and the majority remained in a TEM phenotype. Host-derived CD8+ T-cell phenotype also skewed towards TEM (instead of Tnaive or TCM) in Prf-/- CAR-T group compared to WT CAR-T group. Additionally, spleens derived from Prf-/- CAR-T-treated mice demonstrated increased phagocytosis. These changes in host-derived immune-associated cells suggest that the lack of perforin not only affects CAR-T but may also induce a pro-inflammatory microenvironment through soluble mediators. Among cytokines that we have tested so far (IFNγ, IL-6, TNFα, IL-2, IL-4, IL-17A, IL-10, IL-12p70, MCP-1, GM-CSF), IFNγ has been the only cytokine differentially elevated in vitro and in vivo, comparing Prf-/- to WT CAR-T. IFNγ levels during initial CAR-T expansion phase may be playing a critical role in the persistence of CAR-T. Preliminary results from our ARE-/- CAR-T model also demonstrated that significantly higher serum IFNγ levels during initial CAR-T expansion phase was associated with higher CAR-T in vivo persistence, regardless of antigen availability.Conclusion: Collectively, these data suggest that perforin is dispensable in murine CD19-CAR-T cytotoxic activity, but contributes to CAR-T contraction, and possibly to the regulation of a secondary inflammatory response. We hypothesize that IFNγ may be the major mediator of the observed differences. Experiments are underway to further elucidate the interplay of perforin and INFγ in CAR-mediated cytotoxicity and to determine whether targeting IFNγ may be a therapeutic option in HLH-like CAR toxicity. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Synthesis, antibiotic structure\u2013activity relationships, and cellulose dissolution studies of new room-temperature ionic liquids derived from lignin

BackgroundIonic liquids (ILs) are promising pretreatment solvents for lignocellulosic biomass, but are largely prepared from petroleum precursors. Benzaldehydes from depolymerized lignin, such as vanillin, syringaldehyde, and 4-methoxy benzaldehyde, represent renewable feedstocks for the synthesis of ionic liquids. We herein report syntheses of novel lignin-derived ionic liquids, with extended N-alkyl chains, and examine their melting points, cellulose dissolution capacities, and toxicity profiles against Daphnia magna and E. coli strain 1A1. The latter organism has been engineered to produce isoprenol, a drop-in biofuel and precursor for commodity chemicals.ResultsThe new N,N-diethyl and N,N-dipropyl methyl benzylammonium ILs were liquids at room temperature, showing 75–100 °C decreased melting points as compared to their N,N,N-trimethyl benzylammonium analog. Extension of N-alkyl chains also increased antibacterial activity threefold, while ionic liquids prepared from vanillin showed 2- to 4-fold lower toxicity as compared to those prepared from syringaldehyde and 4-methoxybenzaldehyde. The trend of antibacterial activity for anions of lignin-derived ILs was found to be methanesulfonate < acetate < hydroxide. Microcrystalline cellulose dissolution, from 2 to 4 wt% after 20 min at 100 °C, was observed in all new ILs using light microscopy and IR spectroscopy.ConclusionsIonic liquids prepared from H-, S- and G-lignin oxidation products provided differential cytotoxic activity against E. coli and D. magna, suggesting these compounds could be tailored for application specificity within a biorefinery.

Hormetic Effects of Binaphthyl Phosphonothioates as Pro-oxidants and Antioxidants.

Organophosphorous compounds with such a wide variety in structure, application, and biochemical activities include pesticides, herbicides, nerve agents, medicines, reagents in organic chemistry, and additives for polymers. Binaphthyl phosphono-, phosphorothioates, and their derivatives, are useful chiral catalysts for various asymmetric reactions and are expected to act as heavy metal scavengers. In this study, we aimed to evaluate the neurotoxicity and biochemical properties of a new series of binaphthyl phosphonothioates called KK compounds using the mouse hippocampal HT22 cells. Despite negligible structural difference, the compounds exhibited differential general cytotoxic activity which was independent of acetylcholine esterase inhibition; on the other hand, all compounds tested prevented endogenous oxidative stress by suppressing generation of reactive oxygen species. Among them, KK397, KK387, KK410, and KK421 showed hormesis, i.e., biphasic dose responses to endogenous oxidative stress, characterized by beneficial effect at low dose and toxic effect at high dose. At cytotoxic concentrations, these compounds were potent radical generators and activated intracellular signaling molecules such as the p38 mitogen-activated protein kinase, c-Jun NH2-terminal kinase, growth arrest- and DNA damage-inducible gene 153, X-box binding protein 1, and heme oxygenase 1, which are preferentially activated by cell stress-inducing signals, including oxidative and endoplasmic reticulum stress. These findings indicated that novel binaphthyl phosphonothioates can exhibit multiple biochemical properties, functioning as antioxidants and/or pro-oxidants, depending on the concentration, and chemical modification of binaphthyl organophosphorus compounds endowed them with unique characteristics and multiple beneficial functions.

A Novel Cytotoxic Compound From the Endolichenic Fungus, Xylaria psidii Inhabiting the Lichen, Amandinea medusulina

The lichen host, Amandinea medusulina, collected from mangrove habitats in Sri Lanka, and its associated endolichenic fungi were isolated and identified by rDNA-ITS sequence analysis and morphological features. One of the fungal strains frequently isolated from the lichen thalli was identified as Xylaria psidii. This study aimed at the isolation and identification of the cytotoxic compounds present in this fungus. Secondary metabolites of X. psidii were first extracted into ethyl acetate and subsequently subjected to bioassay-guided fractionation to isolate the bioactive compounds. Sulforhodamine B assay against a lung cancer (NCI-H292) cell line was used to determine the differential cytotoxic activity. Bioassay-guided fractionation led to the isolation of an active compound, SS/02/29/08, showing moderate cytotoxicity (IC50 = 27.2 µg/mL). Its structure was elucidated by IR, 1D- and 2D-NMR, and 13C-NMR spectrophotometry and MS, in combination with HRMS, 13C NMR, HSQC, HMBC, and DQF-COSY. The structure of SS/02/29/08 was determined as ( Z)-3-{(3-acetyl-2-hydroxyphenyl)diazenyl}-2,4-dihydroxybenzaldehyde and identified as a new compound. This novel compound has promising differential cytotoxic activity against human lung cancer cell line (NCI-H292).

The Evaluation of Potential Cytotoxic Effect of Different Proton Pump Inhibitors on Different Human Cancer Cell Lines.

To assess the differential cytotoxic activity of PPIs on different human cancer cell lines; namely A549 lung cancer, CACO-2 colorectal cancer, MCF-7 breast cancer, and PANC-1 pancreatic cancer, A375 skin melanoma. In this study, the five human cancer cell lines and human non-cancerous fibroblasts were treated with increasing concentration of PPIs Omeprazole (OMP), Esomeprazole (ESOM), and Lansoprazole (LANSO) (50-300μM), over 24h, 48h, and 72h. Cell viability was determined using 3-(4,5- Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and the IC50 values of PPIs were measured. The most sensitive cell line A375 was used for further investigation. The cytotoxic effects of LANSO on these cells were assessed using Annexin-V Propidium Iodide (AV-PI) flow cytometry. As of action mechanism; anti-inflammatory effects of each PPIs and PPIs-DOXO combination therapy on LPS-stimulated RAW 264.7 mouse macrophages were assessed. Dose and time dependence cytotoxic activity of PPIs on human cancer cell lines was founded. Unlike DOXO; All PPIs had a selective cytotoxic effect in the normal fibroblasts. Unlike the equipotent OMP and ESOM; LANSO was the most potent drug with IC50 values at 72h of 99, 217, 272, 208, 181μM against A375, A549, CACO-2, MCF-7, and PANC-1, respectively. AV-PI flow cytometry revealed dose-dependent apoptotic effects of LANSO alone and substantially enhanced in DOXO-co-treatments. Interestingly unlike ESOM and OMP, LANSO proved more effective than indomethacin in LPS-stimulated RAW 264.7 macrophages. None of the tested compounds, as well as indomethacin, exerted any cytotoxicity against RAW 264.7 macrophages. PPIs-DOXO lacked potential synergistic combination antiinflammation therapies. This study provides the evidence that PPIs induce a direct and differential cytotoxic activity against human cancer cell line by the induction of the apoptosis. Moreover, PPIs increase cancer cell lines sensitivity to doxorubicin via apoptosis augmentation. Nevertheless, PPIs-DOXO lacked potential synergistic combination therapies in either antiproliferation or anti-inflammation.

Phytochemical Composition of the Decoctions of Greek Edible Greens (Chórta) and Evaluation of Antioxidant and Cytotoxic Properties.

Wild or semi-wild edible greens (chórta) are an integral part of the traditional Greek Mediterranean diet due to their nutritional value, containing various phytonutrients beneficial to human health. Water-based decoctions of chórta are widely consumed in Greek alternative medicine as health promoting agents. This study examined the chemical profile of the decoctions of eight edible plants, Cichorium intybus, C. endivia, C. spinosum, Crepis sancta, Sonchus asper, Carthamus lanatus, Centaurea raphanina, and Amaranthus blitum, by UPLC-ESI-HRMS and HRMS/MS analysis, to determine possibly bioactive constituents. The profiles of the plants from the Asteraceae family are dominated by the presence of phenolic acids and flavonoid derivatives, whereas the A. blitum decoction is rich in triterpene saponins. Interestingly, the Centaurea raphanina decoction was found to be extremely rich in flavanones, particularly in the aglycone pinocembrin. Further phytochemical investigation and fractionation of this extract resulted in the isolation and identification of five compounds: phlorin (1), syringin (2), pinocembrin (3), pinocembroside (4), and pinocembrin-7-O-neohesperidoside (5). The extracts were also tested for their antioxidant and differential cytotoxic activity against tumor cells. C. raphanina was found to be differentially toxic against metastatic tumor cells. In conclusion, we found that Greek edible greens are a rich source of bioactive secondary metabolites and their consumption could contribute to the maintenance of overall health.

Differential Cytotoxic Activity of Essential Oil of Lippia citriodora from Different Regions in Morocco

The aim of this work was to investigate the cytotoxic effect of the essential oil of dried leaves of Lippia citriodora (H.B. & K.) harvested in different regions of Morocco. This effect was evaluated against the P815 murine mastocytoma cell line using the MTT assay. Interestingly, this work demonstrated for the first time that these essential oils exhibited a strong cytotoxic activity against the P815 cell line, with IC50 values ranging from 7.75 to 13.25 μg/ml. This cytotoxicity began early and increased in a dose- and time-dependent manner. The chemical profile of these essential oils was analyzed by gas chromatography coupled to mass spectrometry. Importantly, the difference in terms of major components' contents was not significant suggesting probably that the differential cytotoxicity between these essential oils could be attributed to the difference in the content of these essential oils in minor compounds, which could interact with each other or with the main molecules. Finally, this study demonstrated for the first time that essential oils of L. citriodora from different regions in Morocco induced apoptosis against P815 tumor cell line.

Differential cytotoxic activity of Quercetin on colonic cancer cells depends on ROS generation through COX-2 expression

Quercetin is a bioactive compound with anti-inflammatory, antioxidant and anticancer properties. This study exemplifies the differential cytotoxic activity of Quercetin on two human colonic cancer cell lines, HT29 and HCT15. IC50 of Quercetin for HT29 and HCT15 cells were 42.5 μM and 77.4 μM, respectively. Activation of caspase-3, increased level of cytosolic cytochrome c, decreased levels of pAkt, pGSK-3β and cyclin D1 in 40 μM Quercetin treated HT29 cells alone. Though, nuclear translocation of NFkB was increased in 40 μM Quercetin treated HT29 and HCT15 cells, over expression of COX-2 was observed in 40 μM Quercetin treated HT29 cells, whereas, Quercetin treated HCT15 cells did not expressed COX-2. Increased generation of reactive oxygen species (ROS) was observed only in Quercetin treated HT29 cells, which is due to over expression of COX-2, as COX-2 silencing inhibited Quercetin induced apoptosis and ROS generation. Insilico analysis provided evidence that Quercetin could partially inhibit COX-2 enzyme by binding to subunit A which has peroxidase activity and serves as source of ROS. However, Quercetin showed minimal effect on normal intestinal epithelial cells i,e IEC-6. To conclude, differential sensitivity of two cancer cells, HT29 and HCT15, to Quercetin depends on COX-2 dependent ROS generation that induces apoptosis and inhibits cell survival.

Ginsenoside 20(S)-Rh2 exerts anti-cancer activity through targeting IL-6-induced JAK2/STAT3 pathway in human colorectal cancer cells

Ethnopharmacological relevancePanax ginseng is one of the most well-known medicinal herbs in Korea and China, which has been used for treatment and prevention of cancer, obesity, diabetes, and cardiovascular diseases. Ginsenosides are the major components of P. ginseng, having a wide range of pharmacological activities. Among the ginsenosides, protopanaxadiol (PPD)-types reportedly have potent anti-cancer effects. Rh2 is PPD-type ginsenoside, and two stereoisomeric forms of Rh2 as 20(S)- and 20(R)-Rh2 were selectively isolated recently. Aim of the studyThe biological activities of Rh2 ginsenosides are known to depend on their differences in stereochemistry. Colorectal cancer (CRC) is one of the most lethal neoplasm, and cancer-related death is usually associated with metastasis to other organs. We aimed this study to investigate whether 20(S)- and 20(R)-Rh2 can suppress tumor invasion in human CRC cells. Materials and methods20(S)- and 20(R)-Rh2 were isolated from the roots of ginseng. Human CRC cells were incubated with 20(S)- or 20(R)-Rh2 in the presence or absence of interleukin-6. An MTT assay was used to measure cell viability. Western blot and quantitative real-time PCR analyses were performed to determine levels of expression and phosphorylation. An invasion assay was performed using a Boyden chamber system with the Matrigel-coated membrane to measure cancer cell invasion. Results20(S)- and 20(R)-Rh2 showed differential cytotoxic activity. Only 20(S)-Rh2 decreased cancer cell viability. Additionally, 20(S)-Rh2 effectively inhibited IL-6-induced signal transducer and activator of transcription 3 (STAT3) phosphorylation and the expression of matrix metalloproteinases (MMPs), including MMP-1, −2, and −9, resulting in inhibition of cancer cell invasion. Interestingly, these pharmacological activities of 20(S)-Rh2 were more potent than those of 20(R)-Rh2. Furthermore, combination treatment showed that 20(S)-Rh2 enhanced the sensitization of doxorubicin-treated anti-cancer activities in CRC cells. ConclusionOur results demonstrated that ginsenoside 20(S)-Rh2 has therapeutic potential for the treatment with CRC and may be valuable as a combination partner with more classic chemotherapeutic agents, such as doxorubicin, to treat CRC.

Differential cytotoxic activity of the petroleum ether extract and its furanosesquiterpenoid constituents from Commiphora molmol resin.

This study revealed a differential cytotoxic activity of the petroleum ether extract (IC₅₀ =5 μg/mL) of the resinous exudates of Commiphora molmol against two mouse cell lines KA31T and NIH3T3 (untransformed and transformed mouse fibroblasts, respectively). Four new compounds (1-4) and five known compounds (5-9) were isolated from the petroleum ether extract. The identity of these new compounds was determined as γ-elemane lactone (1), 5-αH,8-βH-eudesma-1,3,7(11)-trien-8,12-olide (2), 2-hydroxy-11,12-dihydrofuranodiene (3), and 2-hydroxyfuranodiene (4). 1 and 2 displayed the highest cytotoxic activity against NIH3T3 cells. 7 and 9 exhibited moderate cytotoxic activity against KA31T cells. Compounds 3-6 showed weak cytotoxic activities against both cell lines. These results may explain the high efficacy of the petroleum ether fraction in several myrrh-derived pharmaceutical preparations.

Differential Cytotoxic Activity of a Novel Palladium-Based Compound on Prostate Cell Lines, Primary Prostate Epithelial Cells and Prostate Stem Cells

The outcome for patients with advanced metastatic and recurrent prostate cancer is still poor. Therefore, new chemotherapeutics are required, especially for killing cancer stem cells that are thought to be responsible for disease recurrence. In this study, we screened the effect of a novel palladium-based anticancer agent (Pd complex) against six different prostate cancer cell lines, and primary cultures from seven Gleason 6/7 prostate cancer, three Gleason 8/9 prostate cancer and four benign prostate hyperplasia patient samples, as well as cancer stem cells selected from primary cultures. MTT and ATP viability assays were used to assess cell growth and flow cytometry to assess cell cycle status. In addition, immunofluorescence was used to detect γH2AX nuclear foci, indicative of DNA damage, and Western blotting to assess the induction of apoptosis and autophagy. The Pd complex showed a powerful growth-inhibitory effect against both cell lines and primary cultures. More importantly, it successfully reduced the viability of cancer stem cells as first reported in this study. The Pd complex induced DNA damage and differentially induced evidence of cell death, as well as autophagy. In conclusion, this novel agent may be promising for use against the bulk of the tumour cell population as well as the prostate cancer stem cells, which are thought to be responsible for the resistance of metastatic prostate cancer to chemotherapy. This study also indicates that the combined use of the Pd complex with an autophagy modulator may be a more promising approach to treat prostate cancer. In addition, the differential effects observed between cell lines and primary cells emphasise the importance of the model used to test novel drugs including its genetic background, and indeed the necessity of using cells cultured from patient samples.

Esculentin-2CHa: A host-defense peptide with differential cytotoxicity against bacteria, erythrocytes and tumor cells

The host-defense peptide, esculentin-2CHa (GFSSIFRGVA10KFASKGLGK D20LAKLGVDLVA30 CKISKQC) shows potent (MIC≤6μM) growth inhibitory activity against clinical isolates of multidrug-resistant strains of Staphylococcus aureus, Acinetobacter baumannii, and Stenotrophomonas maltophilia and differential cytotoxic activity against human erythrocytes (LC50=150μM) and human non-small cell lung adenocarcinoma A549 cells (LC50=10μM). Esculentin-2CHa significantly (P<0.01) stimulates the release of the anti-inflammatory cytokine IL-10 by mouse lymphoid cells and elevates its production after stimulation with concanavalin A and significantly (P<0.05) stimulates TNF-α production by peritoneal macrophages. Effects on IL-6 and IL-1β production were not significant. Removal of the hydrophobic N-terminal hexapeptide (GFSSIF) from esculentin-2CHa results in abolition of growth inhibitory activity against S. aureus and cytotoxic activity against erythrocytes and A549 cells as well as a marked (≥16-fold) reduction in potency against A. baumannii and S. maltophilia. The primary structure of esculentin-2 has been poorly conserved between frog species but evolutionary pressure has acted to maintain the hydrophobic character of this N-terminal hexapeptide sequence. Removal of the cyclic C-terminal domain (CKISKQC) and replacement of the Cys31 and Cys37 residues by serine resulted in appreciable decreases in cytotoxicity against all microorganisms and against mammalian cells. The more cationic [D20K, D27K] analog showed a modest increase in potency against all microorganisms (up to 4-fold) but a marked increase in cytotoxicity against erythrocytes (LC50=11μM) and A549 cells (LC50=3μM).

Synthesis, Characterization, and Molecular Structure of a Novel Zinc (II) Complex: Assessment of Impact of MDR1Pgp Expression on its Cytotoxic Activity

Zinc(II)complex (3) {bis(3-ethoxy-2-hydroxy-benzylidene)-N,N'-bis(2,2-dimethyl-3-aminopropyl)ethylenediamine}-zinc(II); [(3-OEt-ENBDMPI)Zn(II)] was obtained in situ by a ligand exchange reaction involving zinc(II) acetylacetonate and the Schiff-base ligand obtained in situ. For assessing ability of 3 to act as a transport substrate of multidrug resistance (MDR1) P-glycoprotein (Pgp), its cytotoxic activity was evaluated in human epidermal carcinoma drug-sensitive KB 3-1 (Pgp-) and drug resistant KB 8-5 (Pgp+) cells. Compared with its cationic gallium(III) counterpart 4 showing cytotoxicity profiles consistent with its recognition as a Pgp substrate, the neutral zinc(II) complex 3 did not display cytotoxicity profiles (at pharmacologically relevant concentrations <10 µM) modified by expression of Pgp. Further, 3 was found be slightly more toxic against KB 8-5 cells compared to KB 3-1 cells at higher concentration. The neutral zinc (II) complex 3 was also found to be considerably less toxic against Pgp-lacking cells compared to its cationic gallium(III) counterpart 4. Additionally, the neutral zinc(II) complex 3 demonstrated considerably more toxicity against Pgp expressing KB 8-5 cells (> 10 µM) compared with its cationic counterpart 4 displaying minimal effect at highest concentration. The results suggest that differential cytotoxic activity of 3 and 4 in drug-resistant human epidermal carcinoma KB 8-5 (Pgp+) cells could result from variation in the overall charge of the molecules.