Acute Leukemia Cells Research Articles

P-399. Prevalence of gastrointestinal tract colonization by carbapenem-resistant Enterobacterales and vancomycin-resistant Enterococcus faecium in hematological patients at a referral hospital in Mexico City

Abstract Background The prevalence of carbapenem-resistant enterobacteria (CRE) in patients with hematological neoplasias varies due to local epidemiology, antimicrobial prophylaxis and types of hematopoietic stem cell transplants (HSCT). Colonization by CRE is the main risk factor for infection, which carries a mortality up to 65%. This study evaluated CRE colonization in patients with acute leukemia (AL) and HSCT) within 28 days. Secondary goals included describing CRE bloodstream infections (BSI), colonization by Vancomycin-Resistant Enterococci (VRE), ESBL, and quinolone-resistant (QR) microorganisms, risk factors for CRE, and 28-day mortality.Table 1.Risk factors for CRE colonization among patients with acute leukemia and hematopoietic stem cell transplantRR: Relative risk, aHR: Adjusted hazard ratio, allo HSCT: Allogeneic hematopoietic stem cell transplant Methods This was a prospective cohort from March to October 2023 at a referral hospital in Mexico City. We included consenting adults with acute leukemia (AL) receiving induction chemotherapy and HSCT. Patients with prior 90-day CRE colonization or infection were excluded. Weekly stool screening, using the adapted CDC method, was performed throughout hospitalization, with a follow-up period of 28 days or until discharge or death. CRE were identified by MALDITOF-MS (Bruker), susceptibility testing done by Vitek2 (Biomérieux), using CDC breakpoints. Descriptive analysis was done for CRE colonization and mortality. A multivariate analysis for CRE colonization through logistic regression was done. Results Among 37 patients included, a CRE colonization prevalence of 21.8% was found, of which, 12.5% developed BSI compared to 3.5% of non-colonized individuals. Additionally, colonization rates for VRE, ESBL, and QR microorganisms were 5.4%, 35.1%, and 32.4%, respectively. Independent factors related to CRE colonization were older age and prior 6-month carbapenem use. 28-day mortality was 10.8%, with no differences between colonized and non-colonized groups. VRE colonization was significantly associated with VRE infection (p=0.04). CRE colonization resulted in increased 90-day mortality (50% vs. 10.3%, p=0.011). Conclusion The prevalence of CRE colonization in patients with AL or HSCT was 21.8%. It was associated with older age and prior carbapenem use and resulted in increased 90-day mortality. Colonization by ESBL and QR were frequent. Disclosures All Authors: No reported disclosures

Metabolic adaptations to acute glucose uptake inhibition converge upon mitochondrial respiration for leukemia cell survival

One hallmark of cancer is the upregulation and dependency on glucose metabolism to fuel macromolecule biosynthesis and rapid proliferation. Despite significant pre-clinical effort to exploit this pathway, additional mechanistic insights are necessary to prioritize the diversity of metabolic adaptations upon acute loss of glucose metabolism. Here, we investigated a potent small molecule inhibitor to Class I glucose transporters, KL-11743, using glycolytic leukemia cell lines and patient-based model systems. Our results reveal that while several metabolic adaptations occur in response to acute glucose uptake inhibition, the most critical is increased mitochondrial oxidative phosphorylation. KL-11743 treatment efficiently blocks the majority of glucose uptake and glycolysis, yet markedly increases mitochondrial respiration via enhanced Complex I function. Compared to partial glucose uptake inhibition, dependency on mitochondrial respiration is less apparent suggesting robust blockage of glucose uptake is essential to create a metabolic vulnerability. When wild-type and oncogenic RAS patient-derived induced pluripotent stem cell acute myeloid leukemia (AML) models were examined, KL-11743 mediated induction of mitochondrial respiration and dependency for survival associated with oncogenic RAS. Furthermore, we examined the therapeutic potential of these observations by treating a cohort of primary AML patient samples with KL-11743 and witnessed similar dependency on mitochondrial respiration for sustained cellular survival. Together, these data highlight conserved adaptations to acute glucose uptake inhibition in diverse leukemic models and AML patient samples, and position mitochondrial respiration as a key determinant of treatment success.

UNC119 regulates T-cell receptor signalling in primary T cells and T acute lymphocytic leukaemia.

T-cell receptor recognition of cognate peptide-MHC leads to the formation of signalling domains and the immunological synapse. Because of the close membrane apposition, there is rapid exclusion of CD45, and therefore LCK activation. Much less is known about whether spatial regulation of the intracellular face dictates LCK activity and TCR signal transduction. Moreover, as LCK is a driver in T acute lymphocytic leukaemia, it is important to understand its regulation. Here, we demonstrate a direct role of the ciliary protein UNC119 in trafficking LCK to the immunological synapse. Inhibiting UNC119 reduces localisation of LCK without impairing LCK phosphorylation and reduces T-cell receptor signal transduction. Although important for initial LCK reorganisation, activated CD8+ T cells retained their ability to kill target tumour cells when UNC119 was inhibited. UNC119 was also needed to sustain proliferation in patient-derived T-ALL cells. UNC119 may therefore represent a novel therapeutic target in T acute lymphocytic leukaemia, which alters the subcellular localisation of LCK in T acute lymphocytic leukaemia cells but preserves the function of existing cytotoxic lymphocytes.

In Vitro, In Vivo, Ex Vivo Characterisation of Dihydroimidazotriazinones and Their Thermal Decomposition Course Studied by Coupled and Simultaneous Thermal Analysis Methods.

The biological and thermal properties of a class of synthetic dihydroimidazotriazinones were disclosed in this article for the first time. Molecules 1-6-as potential innovative antimetabolites mimicking bicyclic aza-analogues of isocytosine-were evaluated for their in vitro anticancer activity. Moreover, in vivo, in vitro, and ex vivo toxicity profiles of all the compounds were established in zebrafish, non-tumour cell, and erythrocyte models, respectively. Their antihaemolytic activity was also evaluated. Additionally, the thermal decomposition mechanism, path, and key thermal properties of heterocycles 1-6 were analysed. It was found that all the studied compounds revealed significant antiproliferative activities against tumour cells of the lung, cervix, ovary, and breast, as well as acute promyelocytic leukaemia cells, superior or comparable to that of an anticancer agent gemcitabine. Most of them were less toxic to non-tumour cells than this standard drug, and none had a haemolytic effect on red blood cells. All the tested heterocycles proved to be safer for zebrafish than a standard drug pemetrexed. Some exhibited the ability to inhibit oxidative haemolysis, suggesting their protective action on erythrocytes. The differential scanning calorimetry (DSC) analyses confirmed that all molecules melted within one narrow temperature range, proving their purity. The melting points depended solely on the type of substituent and increased as follows: 4 (R = 3-ClPh) < 2 (R = 4-CH3Ph) = 3 (R = 4-OCH3Ph) < 5 (R = 4-ClPh) = 1 (R = Ph) < 6 (R = 3,4-Cl2Ph). The thermogravimetry/differential thermogravimetry (TG/DTG) studies confirmed high thermal stability of all the investigated heterocycles in inert (>230 °C) and oxidising (>260 °C) atmospheres, which depended directly on the R. The pyrolysis process included one main decomposition stage and was connected with the emission of NH3, HCN, CH3CN, HNCO, alkane, alkene, aromatic fragments, CO2 (for all the compounds), and HCl (for the molecule with 3,4-Cl2Ph), which was confirmed by FTIR and QMS analyses. In turn, the oxidative decomposition process of the tested polyazaheterocycles took place in two main stages connected with the formation of the same volatiles as those observed in an inert atmosphere and additionally with the release of N2, NO, CO, and H2O. These results proved that the pyrolysis and oxidative decomposition run through the radical mechanism connected with the additional reactions between radicals and oxygen in synthetic air. The favourable biological and thermal properties of this class of dihydroimidazotriazinones imply their usefulness as potential pharmaceutics.

RETRACTION: Kaempferol Increases Apoptosis in Human Acute Promyelocytic Leukemia Cells and Inhibits Multidrug Resistance Genes.

M. Moradzadeh, A. Tabarraei, H. R. Sadeghnia, A. Ghorbani, A. Mohamadkhani, S. Erfanian, and A. Sahebkar, "Kaempferol Increases Apoptosis in Human Acute Promyelocytic Leukemia Cells and Inhibits Multidrug Resistance Genes," Journal of Cellular Biochemistry 119, no. 2 (2018): 2288-2297, https://doi.org/10.1002/jcb.26391. The above article, published online on October 20, 2017 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Christian Behl; and Wiley Periodicals LLC. The retraction has been agreed upon following an investigation into concerns raised by a third party, which revealed inappropriate image panel duplications between this article (Figure 5A,B) and other articles published by an overlapping group of authors, in which the images represent different experimental conditions. The explanation provided by the authors could not address these concerns. Thus, the editors have lost confidence in the presented data and consider the conclusions of this manuscript substantially compromised. A. Sahebkar disagrees with the retraction, the other co-authors remained unresponsive.

Unveiling the link between NADPH oxidase 2 activation and mitochondrial superoxide formation in leukemic cell killing induced by arsenic trioxide.

This study focused on the interplay between NADPH oxidase 2 (NOX 2) activation and mitochondrial superoxide (mitoO2.-) formation induced by clinically relevant concentrations of arsenic trioxide (ATO; As2O3) in acute promyelocytic leukemia (APL) cells. Carefully controlled inhibitor studies and small interfering RNA mediated downregulation of p47phox (a component of the NOX 2 complex) expression demonstrated that, in an APL cell line, ATO promotes upstream NOX 2 activation critically connected with the formation of mitoO2.- and with the ensuing mitochondrial permeability transition (MPT)-dependent apoptosis. Instead, acute myeloid leukemia (AML) cell lines respond to ATO with low NOX 2 activation, resulting in a state that is non-permissive for mitoO2.- formation. Consistently, through rescue experiments, we demonstrate that pharmacological stimulation of NOX 2 overcomes resistance in these cells, thereby initiating the same cascade of downstream events observed in APL cells. As a final note, several lines of evidence, including measurement of glutathione, catalase and glutathione peroxidase levels, indicated that the antioxidant machinery was similar in APL and AML cells. The results regarding nuclear factor erythroid 2 p45-related factor 2-dependent antioxidant responses were instead of more complex interpretation as NB4 cells appeared particularly responsive to ATO. Our findings allow a novel interpretation of the interplay between NOX 2 activation and mitoO2.- formation induced by ATO, ultimately steering leukemic cells towards MPT-dependent apoptosis. These mechanistic insights provide a rationale for the disparate responses of APL and AML cells to ATO, offering potential avenues for the development of therapeutic intervention tailored to specific leukemia subtypes.

The Anticancer Activity of Cannabinol (CBN) and Cannabigerol (CBG) on Acute Myeloid Leukemia Cells.

Several cannabis plant-derived compounds, especially cannabinoids, exhibit therapeutic potential in numerous diseases and conditions. In particular, THC and CBD impart palliative, antiemetic, as well as anticancer effects. The antitumor effects include inhibition of cancerous cell growth and metastasis and induction of cell death, all mediated by cannabinoid interaction with the endocannabinoid system (ECS). However, the exact molecular mechanisms are still poorly understood. In addition, their effects on leukemia have scarcely been investigated. The current work aimed to assess the antileukemic effects of CBN and CBG on an acute monocytic leukemia cell line, the THP-1. THP-1 cell viability, morphology and cell cycle analyses were performed to determine potential cytotoxic, antiproliferative, and apoptotic effects of CBN and CBG. Western blotting was carried out to measure the expression of the proapoptotic p53. Both CBN and CBG inhibited cell growth and induced THP-1 cell apoptosis and cell cycle arrest in a dose- and time-dependent manner. CBN and CBG illustrated different dosage effects on THP-1 cells in the MTT assay (CBN > 40 μΜ, CBG > 1 μM) and flow cytometry (CBN > 5 μM, CBG > 40 μM), highlighting the cannabinoids' antileukemic activity. Our study hints at a direct correlation between p53 expression and CBG or CBN doses exceeding 50 μM, suggesting potential activation of p53-associated signaling pathways underlying these effects. Taken together, CBG and CBN exhibited suppressive, cell death-inducing effects on leukemia cells. However, further in-depth research will be needed to explore the molecular mechanisms driving the anticancer effects of CBN and CBG in the leukemia setting.

AKR1B1 is Required for Maintaining Acute Leukemia Cell Survival by Epigenetic Silencing of Tumor Suppressor Genes.

AKR1B1 is a member of aldo-keto-reductase (AKR) superfamily which catalyze the reduction of carbonyl groups to hydroxyl groups in NADPH-dependent ways. Previous studies have shown that AKR1B1 promotes cancer progression, but its exact role in acute leukemia was unclear. Cell counting and Luminescent Cell Viability Assay were performed to measure the cell proliferation and viability. Soft-Agar Colony Formation (CFU) assay was conducted to measure the capacity of single cells to form colonies in vitro. Cell apoptosis, cell cycle, and cell differentiation were assessed by flow cytometry. Western blotting and RT-qPCR were utilized to examine AKR1B1 expression in acute leukemia cells. In vivo leukemia growth and mouse survival were evaluated using a model of xenotransplantation mice. We explored the AKR1B1 effect and mechanism in acute leukemia cells using RNA-sequencing technology and transcriptomic analysis. AKR1B1 is highly expressed in acute leukemia cells. Knockdown of AKR1B1 inhibited acute leukemia cell proliferation, colony-forming capability, and cell cycle and promoted apoptosis. Additionally, xenograft experiments proved that knockdown of AKR1B1 delayed the progression of acute leukemia cell in vivo. RNA-sequencing data analysis demonstrated that AKR1B1 was involved in the epigenetic silencing of H3K27me3-targeted genes. EZH2 inhibitor UNC1999 combined with knockdown of AKR1B1 showed synergistic inhibitory effect on acute leukemia cells. AKR1B1 is essential for the leukemogenesis and may serve as a potential therapeutic target to treat acute leukemia patients.

Depletion of Tregs from CD4+ CAR-Tcells enhances the tumoricidal effect of CD8+ CAR-Tcells in anti-CD19 CAR-T therapy.

Chimeric antigen receptor T (CAR-T) cell therapy, which targets CD19 for hematological malignancies, represents a breakthrough in cancer immunotherapy. However, some patients may develop resistance to CAR-T treatment, underscoring the importance of optimizing CAR-T design to enhance responsiveness. Here, we investigated the impact of different subpopulations in anti-CD19 CAR-T cells on the tumoricidal effect. Different populations of anti-CD19 CAR-T cells were isolated by magnetic-activated cell sorting (MACS). Their lytic activities on the acute lymphocytic leukemia cell line SUP-B15 and diffuse large B-cell lymphoma EB-3 cell line were examined in a co-culture system. The anti-tumorigenic outcome of different CAR-T cell compositions was evaluated in a xenograft mouse model of EB-3 cells. CD8+CAR-T cells exhibited the most potent tumoricidal activity against SUP-B15 and EB-3 cells. Additionally, CD4+ T helper cells enhanced the lytic effects of CD8+ CAR-T cells by increasing the availability of interleukin-2 (IL-2). Depleting CD25+Treg (T regulatory) cells from CD4+CAR-T population further augmented the tumoricidal activity of CD8+CAR-T cells by preventing IL-2 deprivation. Consistently, in vivo experiments demonstrated that the CD4+CD25+ Treg population dampened the antitumor activity of CD8+CAR-T cells, while depletion of Tregs from CD4+CAR-T cells enhanced the tumoricidal effect. These findings emphasize the potential role of CAR Treg cells in therapeutic resistance, suggesting that the depletion of Tregs in the anti-CD19 CAR-T population may serve as a strategy to augment the anticancer effect of CD8+CAR-T cells.

Effects of ERK1/2 Inhibitors on the Growth of Acute Leukemia Cells.

Extracellular signal-regulated kinases (ERK)1/2 are important regulatory proteins that control cell proliferation and survival, playing a significant role in cancer progression, metastasis, and chemoresistance. This study investigated the effects of ERK1/2 inhibitors on the in vitro growth of acute leukemia cell lines. Three ERK1/2 inhibitors were used: SCH772984, temuterkib (LY3214996), and ulixertinib (BVD-523). Four acute myeloid leukemia cell lines (OCI/AML3, HL-60, THP-1, and U-937) and two T-lymphoblastic leukemia cell lines (Jurakt and KOPT-K1) were treated with these inhibitors. Cell growth was assessed using a colorimetric assay, and cell-cycle progression and apoptosis were analyzed using flow cytometry. The expression of intracellular signaling proteins was evaluated via immunoblotting. The effects of small interfering RNA (siRNA)-mediated ERK1/2 knockdown were also evaluated. The inhibitors suppressed the growth of three leukemia cell lines (OCI/AML3, HL-60, and THP-1) harboring neuroblastoma rat sarcoma virus (NRAS) mutations. Growth suppression occurred through G0/G1 arrest in all three cell lines and through apoptosis in OCI/AML3 cells. Immunoblotting demonstrated that these inhibitors suppressed the expression of MYC proto-oncogene, bHLH transcription factor (MYC), in the three cell lines. The additional molecular mechanisms of growth suppression varied depending on the specific inhibitor and cell line. The inhibitors had milder suppressive effects on normal lymphocytes compared to the leukemia cell lines. ERK1/2 inhibitors may serve as novel molecular-targeted drugs for treating leukemia with NRAS mutations.

A Core NRF2 Gene Set Defined Through Comprehensive Transcriptomic Analysis Predicts Selective Drug Resistance and Poor Multicancer Prognosis.

Aims: The nuclear factor erythroid 2-related factor 2-Kelch-like ECH-associated protein 1 (NRF2-KEAP1) pathway plays an important role in the cellular response to oxidative stress but may also contribute to metabolic changes and drug resistance in cancer. However, despite its pervasiveness and important role, most of nuclear factor erythroid 2-related factor 2 (NRF2) target genes are defined in context-specific experiments and analysis, making it difficult to translate from one situation to another. Our study investigates whether a core NRF2 gene signature can be derived and used to represent NRF2 activation in various contexts, allowing better reproducibility and understanding of NRF2. Results: We define a core set of 14 upregulated NRF2 target genes from 7 RNA-sequencing datasets that we generated and analyzed. This NRF2 gene signature was validated using analyses of published datasets and gene sets. An NRF2 activity score based on expression of these core target genes correlates with resistance to drugs such as PX-12 and necrosulfonamide but not to paclitaxel or bardoxolone methyl. We validated these findings in our Kelch-like ECH-associated protein 1 (KEAP1) knockout cancer cell lines. Finally, our NRF2 score is prognostic for cancer survival and validated in additional independent cohorts for lung adenocarcinoma and also novel cancer types not associated with NRF2-KEAP1 mutations such as clear cell renal carcinoma, hepatocellular carcinoma, and acute myeloid leukemia. Innovation and Conclusions: These analyses define a core NRF2 gene signature that is robust, versatile, and useful for evaluating NRF2 activity and for predicting drug resistance and cancer prognosis. Using this gene signature, we uncovered novel selective drug resistance and cancer prognosis associated with NRF2 activation. Antioxid. Redox Signal. 41, 1031-1050.

Metabolic Adaptations To Acute Glucose Uptake Inhibition Converge Upon Mitochondrial Respiration For Leukemia Cell Survival.

One hallmark of cancer is the upregulation and dependency on glucose metabolism to fuel macromolecule biosynthesis and rapid proliferation. Despite significant pre-clinical effort to exploit this pathway, additional mechanistic insights are necessary to prioritize the diversity of metabolic adaptations upon acute loss of glucose metabolism. Here, we investigated a potent small molecule inhibitor to Class I glucose transporters, KL-11743, using glycolytic leukemia cell lines and patient-based model systems. Our results reveal that while several metabolic adaptations occur in response to acute glucose uptake inhibition, the most critical is increased mitochondrial oxidative phosphorylation. KL-11743 treatment efficiently blocks the majority of glucose uptake and glycolysis, yet markedly increases mitochondrial respiration via enhanced Complex I function. Compared to partial glucose uptake inhibition, dependency on mitochondrial respiration is less apparent suggesting robust blockage of glucose uptake is essential to create a metabolic vulnerability. When wild-type and oncogenic RAS patient-derived induced pluripotent stem cell acute myeloid leukemia (AML) models were examined, KL-11743 mediated induction of mitochondrial respiration and dependency for survival associated with oncogenic RAS. Furthermore, we examined the therapeutic potential of these observations by treating a cohort of primary AML patient samples with KL-11743 and witnessed similar dependency on mitochondrial respiration for sustained cellular survival. Together, these data highlight conserved adaptations to acute glucose uptake inhibition in diverse leukemic models and AML patient samples, and position mitochondrial respiration as a key determinant of treatment success.

Anticancer effects of pomegranate-derived peptide PG2 on CDK2 and miRNA-339-5p-mediated apoptosis via extracellular vesicles in acute leukemia

Acute leukemia has rapid onset and severe complications. Anticancer peptides from natural sources have demonstrated efficacy in eliminating various cancers through apoptosis signaling pathways. Additionally, extracellular vesicles containing microRNAs play pivotal roles in promoting tumorigenesis. Therefore, this study aimed to investigate the impact of PG2, a pomegranate peptide that regulates extracellular vesicles, on the induction of acute leukemia cell apoptosis. NB4 and MOLT-4 leukemia cell lines were treated with PG2 alone or in combination with daunorubicin to assess cell viability using the MTT assay. Extracellular vesicles were extracted from PG2-treated NB4 and MOLT-4 cells. Bioinformatic tools were utilized to predict target proteins and microRNAs, following which mRNA and protein expression were determined by using RT‒qPCR and western blotting, respectively. PG2 significantly reduced the viability of NB4 and MOLT-4 cells. Furthermore, the combination of PG2 with daunorubicin had a synergistic effect on NB4 and MOLT-4 cells. Subsequent treatment with PG2 or PG2-treated extracellular vesicles decreased CDK2 expression while increasing microRNA-339-5p and caspase-3 expression in NB4 and MOLT-4 cells. Our findings revealed that the anticancer activity of PG2 through the CDK2/miR-339-5p/caspase-3 pathway is mediated by extracellular vesicles, ultimately inducing apoptosis. PG2 holds promise as a potential antileukemic drug.

Enhancing Gene Delivery in NB-4 Cells: Overcoming Transduction and Selection Challenges.

Efficient gene transduction and cell viability are critical factors in genetic manipulation for research and therapeutic purposes. In this study, we explored the challenges associated with transducing the NB-4 cell line, a well-established model for acute promyelocytic leukemia (APL), using lentiviral vectors. While the initial transduction efficiency in NB-4 cells reached approximately 30%, we observed a significant decrease in cell viability, a phenomenon not observed in other acute leukemia cell lines such as THP-1 cells. We identified that this toxicity could be mitigated by purifying viral particles through ultracentrifugation or polyethylene glycol (PEG) precipitation, indicating that toxic substances, potentially secondary metabolites released by HEK293, could be responsible for the cell death. Nevertheless, cell selection by puromycin was still ineffective; crucially, we discovered that the human phosphoglycerate kinase (hPGK) promoter, commonly used in the PLKO1 vector, may become silenced in NB-4 cells, preventing effective selection with puromycin. By replacing the hPGK promoter with the elongation factor-1 alpha (EF1α) promoter, we successfully achieved high transduction efficiency and robust selection, demonstrating the potential for this modified vector system to facilitate genetic studies in APL models. These findings provide important insights into optimizing gene transduction protocols not only for NB-4 cells but also for other challenging cell lines, offering a refined approach for gene delivery and selection in cell models.

Investigation of Apoptosis-mediated Cytotoxic Effects of Royal Jelly on HL-60 Cells

In recent years, the use of nontoxic natural products that can be effective on cancer cells as new agents has attracted the attention of scientists in order to reduce the negative side effects of existing cancer drugs and their toxicity to normal cells. Some in vivo and in vitro studies have shown that royal jelly (RJ) inhibits cell proliferation and induces apoptosis. In this research, we aimed to investigate the effects of RJ on proliferative and apoptotic processes in the human acute promyelocytic leukemia cell line (HL-60). The HL60 cell line was treated with different concentrations of RJ for 24, 48, and 72 hours. The half maximum inhibitory concentration (IC50) of RJ was determined using 3-(4.5 dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide test (MTT) and the proliferation activity of HL-60 cells was evaluated. Flow cytometry analysis was performed to measure apoptosis in HL-60 cells. IC50 values for RJ were calculated as 13.98, 6.45, and 2.06 mg/mL for 24, 48, and 72 hours, respectively. Flow cytometry results also showed that RJ had apoptotic effects at the concentrations found. The results showed that RJ treatment significantly induced apoptosis and reduced the proliferation of HL-60 cells. This study shows that RJ can be a complementary treatment against HL-60 acute myeloid leukemia cells due to its anticancer and antiproliferative effects.

High glucose condition aggravates inflammatory response induced by Porphyromonas gingivalis in THP-1 macrophages via autophagy inhibition

BackgroundPorphyromonase gingivalis (P. gingivalis) is a type of bacteria that causes periodontitis, which is strongly correlated with systemic diseases such as diabetes. However, the effect of hyperglycemia on periodontitis are unclear. The present study examined the effects of high glucose levels on the response to P. gingivalis infection.ResultsThe expression of P. gingivalis-induced interleukin-1β (IL-1β) and inflammasomes increased as the glucose concentration increased. High glucose conditions suppressed P. gingivalis–induced autophagy in human acute monocytic leukemia cell line (THP-1) macrophages. Zingerone increased autophagy and alleviated P. gingivalis-induced inflammatory response in THP-1 macrophages under high glucose conditions. In addition, P. gingivalis- induced inflammation in bone marrow-derived macrophages of diabetic mice was higher than in wild-type mice, but a zingerone treatment decreased the levels. Alveolar bone loss due to a P. gingivalis infection was significantly higher in diabetic mice than in wild-type mice.ConclusionsHigh-glucose conditions aggravated the inflammatory response to P. gingivalis infection by suppressing of autophagy, suggesting that autophagy induction could potentially to treat periodontitis in diabetes. Zingerone has potential use as a treatment for periodontal inflammation induced by P. gingivalis in diabetes patients.

Engineering Tk1656, a highly active l-asparaginase from Thermococcus kodakarensis, for enhanced activity and stability

l-Asparaginases catalyze the hydrolysis of l-asparagine to l-aspartic acid and ammonia. These enzymes have potential applications in therapeutics and food industry. Tk1656, a highly active and thermostable l-asparaginase from Thermococcus kodakarensis, has been proved effective in selective killing of acute lymphocytic leukemia cells and in reducing acrylamide formation in baked and fried foods. However, it displayed <5 % activity under physiological conditions compared to the optimal activity at 85 °C and pH 9.5. We have attempted engineering of this valuable enzyme to improve the characteristics required for therapeutic and industrial applications. Based on the literature and crystal structure of Tk1656, nine specific mutant variants were designed, produced in Escherichia coli, and the purified mutant enzymes were compared with the wild-type. One of the mutants, K299L, displayed >20 % increase in activity at 85 °C. H158S substitution resulted in >5 °C increase in the optimal temperature. Similarly, a mesophilic-like mutation L56D, resulted in >5-fold increase in activity at pH 7.0 and 37 °C compared to that of the wild-type enzyme. The substrate specificity of the mutant variants remained unchanged. These results demonstrate that L56D and K299L variants of Tk1656 are the potent enzymes for therapeutics and acrylamide mitigation applications, respectively.

Esculin-Induced Apoptosis and Suppression of Leukemia Surface Markers in HL-60 and THP-1 Cells: A Potential Selective Anticancer Agent

Esculin, a natural coumarin compound primarily derived from Cortex fraxini, is known for its anti-inflammatory and antioxidant properties. Leukemia, a type of hematological cancer, is characterized by the uncontrolled proliferation of white blood cells and has high mortality rates. In this study, we aimed to investigate the potential anticancer effects of esculin (Esculetin-6-Glucoside) on leukemia cell lines, focusing on how this compound could be utilized in cancer treatment through apoptotic pathways. Our experiments used acute promyelocytic leukemia (HL-60) and acute monocytic leukemia (THP-1) cell lines. Cancer cell counting and viability analyses were conducted using the MTS assay(5-(3-carboxymethoxyphenyl)-2-(4,5-dimethylthiazol)-3-(4-sulfophenyl) tetrazolium inner salt assay). Apoptosis was assessed using FITC-labeled Annexin V and propidium iodide. Caspase-3 activation, cytochrome C release, leukemia cell surface markers, and mitochondrial membrane potential (MMP) were analyzed via flow cytometry. Our results demonstrated that esculin can induce apoptosis in leukemia cell lines. Additionally, leukemia surface markers post-treatment were statistically significantly reduced post-treatment in both cell lines. HL-60 and THP-1 cells exhibited different cellular responses in terms of MMP, Caspase-3, and Cytochrome C activities; HL-60 cells were more resistant to esculin treatment, while THP-1 cells were more sensitive. These findings suggest that esculin could become a potential agent in cancer treatment by targeting apoptotic pathways. However, more in vivo studies and preclinical modeling are needed to understand the anticancer effects of esculin fully. Evaluating its efficacy against different cancer types could further expand the therapeutic potential of this compound.

Phenolic Bisabolane Sesquiterpene Derivatives from an Arctic Marine-derived Fungus Aspergillus sydowii MNP-2

Background:: Filamentous fungi in the genus Aspergillus are well known for their important roles in production of bioactive secondary metabolites with diversely chemical structures and potential application in pharmaceutical industry. Objective:: The present study aimed to investigate the phenolic bisabolane sesquiterpene (PBS) derivatives from an Arctic marine-derived fungus Aspergillus sydowii MNP-2. Methods:: In this study, antimicrobial activities were carried out according to the broth microdilution assay, nitric oxide (NO) production in mouse macrophages (RAW264.7) and BV2 microglial cells was used to detect the inhibitory effect of compounds in inflammatory reactions, and in vitro inhibitory cell proliferation activity was determined by the cell counting kit-8 (CCK-8) assay. Results:: In this work, chemical investigation of an Arctic marine-derived strain A. sydowii MNP-2 led to the isolation of 11 PBSs (1-11) using various chromatographic methods. Their chemical structures were unambiguously determined by 1H NMR spectroscopy and mass spectrometry analyses as well as comparison with literature data. It is noteworthy that compounds 1, 7 and 11 were firstly obtained from A. sydowii. Antimicrobial assay showed that these chemicals had no potent inhibitory effect on Staphylococcus aureus, Escherichia coli, and Candida albicans with MIC values &gt; 16 μg/mL. Additionally, the inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)- induced inflammation in mouse macrophages (RAW264.7) and BV2 microglial cells were all below 10% for compounds 4-6 and 8, indicating almost negligible anti-inflammatory efficacy. Among the tested compounds 4-6 and 8 for tumor-cell proliferation inhibition activities, compound 5 demonstrated the strongest inhibitory effect against human acute promyelocytic leukemia cells (HL-6) with a 44.76% inhibition rate. Conclusion:: In the present study, 11 PBS derivatives were purified and characterized from the solidand liquid-state fermentations of the Arctic marine-derived fungus A. sydowii MNP-2. Unfortunately, none of these metabolites had significant antimicrobial, anti-inflammatory, or tumor-cell proliferation inhibition activities.

Immunomodulatory and Antioxidative Effects of Vanillin on Human Acute Monocytic Leukemia Cells: A Potential Therapeutic Approach for AMoL

Immunomodulatory and Antioxidative Effects of Vanillin on Human Acute Monocytic Leukemia Cells: A Potential Therapeutic Approach for AMoL