Contemporary Approach to the Diagnosis and Classification of Myelodysplastic Neoplasms/Syndromes-Recommendations From the International Consortium for Myelodysplastic Neoplasms/Syndromes (MDS [icMDS]).

Myelodysplastic neoplasms/syndromes (MDS) are a heterogeneous group of biologically distinct entities characterized by variable degrees of ineffective hematopoiesis. Recently, 2 classification systems (the 5th edition of the World Health Organization Classification of Haematolymphoid tTumours and the International Consensus Classification) further subcharacterized MDS into morphologically and genetically defined groups. Accurate diagnosis and subclassification of MDS require a multistep systemic approach. The International Consortium for MDS (icMDS) summarizes a contemporary, practical, and multimodal approach to MDS diagnosis and classification.

Prognostic value of European LeukemiaNet 2022 criteria and genomic clusters using machine learning in older adults with acute myeloid leukemia.

This study aimed to validate the new European Leukemia Net (ELN) 2022 criteria for genetic risk stratification in older adults with acute myeloid leukemia (AML) and to determine the most likely set of clusters of similar cytogenetic and mutation properties correlated with survival outcomes in three treatment groups: intensive chemotherapy (IC), hypomethylating agents (HMA) alone, and HMA plus venetoclax (HMA/VEN). The study included 279 patients (aged ≥60 years) who received IC (N=131), HMA (N=76), and HMA/VEN (N=72) between July 2017 and October 2021. No significant differences were observed in survival among the groups according to ELN 2022 risk stratification. Unsupervised hierarchical clustering analysis identified nine genomic clusters (C1-9) with varying survival outcomes depending on treatment type. For example, C4 (predominant for core binding factor-AML) displayed a favorable prognosis in the IC group, but not in the HMA or HMA/VEN groups. The HMA/VEN group had better outcomes than the HMA group in many clusters (C1, 2, 3, and 5); however, the addition of VEN to HMA or IC did not improve the survival outcomes compared with those of HMA alone in C7 and C9 (predominant for -5, del(5q), -7, -17/abn(17p), complex karyotypes, and mutated TP53). The study highlights the limitations of ELN genetic risk stratification in older adults with AML. It emphasizes the need for a more comprehensive approach that considers co-occurring somatic mutations to guide treatment selection in older adults with AML.

A multicenter phase Ib trial of the histone deacetylase inhibitor entinostat in combination with pembrolizumab in patients with myelodysplastic syndromes/neoplasms or acute myeloid leukemia refractory to hypomethylating agents.

Patients with myelodysplastic syndromes/neoplasms (MDS) or acute myeloid leukemia (AML) with hypomethylating agent failure have a poor prognosis. Myeloid-derived suppressor cells (MDSCs) can contribute to MDS progression and mediate resistance to anti-PD1 therapy. As histone deacetylase inhibitors (HDACi) decrease MDSCs in preclinical models, we conducted an investigator-initiated, NCI-Cancer Therapy Evaluation Program-sponsored, multicenter, dose escalation, and expansion phase Ib trial (NCT02936752) of the HDACi entinostat and the anti-PD1 antibody pembrolizumab. Twenty-eight patients (25 MDS and 3 AML) were enrolled. During dose escalation (n=13 patients), there was one dose-limiting toxicity (DLT) on dose level (DL) 1 (G5 pneumonia/bronchoalveolar hemorrhage) and two DLTs at DL 2 (G3 pharyngeal mucositis and G3 anorexia). Per the 3 + 3 dose escalation design, DL 1 (entinostat 8 mg PO days 1 and 15 + pembrolizumab 200 mg IV day 1 every 21 days) was expanded and another 15 patients were enrolled. Hematologic adverse events (AEs) were common. The most common non-hematologic ≥G3 AEs were infection (32%), hypoxia/respiratory failure (11%), and dyspnea (11%). There were no protocol-defined responses among the 28 patients enrolled. Two patients achieved a marrow complete remission (mCR). Using a systems immunology approach with mass cytometry and machine learning analysis, mCR patients had increased classical monocytes and macrophages but there was no significant change of MDSCs. In conclusion, combining entinostat with pembrolizumab in patients with advanced MDS and AML was associated with limited clinical efficacy and substantial toxicity. Absence of an effect on MDSCs could be a potential explanation for the limited efficacy of this combination. ClinicalTrial.gov Identifier: NCT02936752.

VISTA (PD-1H) Is a Crucial Immune Regulator to Limit Pulmonary Fibrosis.

VISTA (V domain immunoglobulin suppressor of T cell activation, also called PD-1H [programmed death-1 homolog]), a novel immune regulator expressed on myeloid and T lymphocyte lineages, is upregulated in mouse and human idiopathic pulmonary fibrosis (IPF). However, the significance of VISTA and its therapeutic potential in regulating IPF has yet to be defined. To determine the role of VISTA and its therapeutic potential in IPF, the expression profile of VISTA was evaluated from human single-cell RNA sequencing data (IPF Cell Atlas). Inflammatory response and lung fibrosis were assessed in bleomycin-induced experimental pulmonary fibrosis models in VISTA-deficient mice compared with wild-type littermates. In addition, these outcomes were evaluated after VISTA agonistic antibody treatment in the wild-type pulmonary fibrosis mice. VISTA expression was increased in lung tissue-infiltrating monocytes of patients with IPF. VISTA was induced in the myeloid population, mainly circulating monocyte-derived macrophages, during bleomycin-induced pulmonary fibrosis. Genetic ablation of VISTA drastically promoted pulmonary fibrosis, and bleomycin-induced fibroblast activation was dependent on the interaction between VISTA-expressing myeloid cells and fibroblasts. Treatment with VISTA agonistic antibody reduced fibrotic phenotypes accompanied by the suppression of lung innate immune and fibrotic mediators. In conclusion, these results suggest that VISTA upregulation in pulmonary fibrosis may be a compensatory mechanism to limit inflammation and fibrosis, and stimulation of VISTA signaling using VISTA agonists effectively limits the fibrotic innate immune landscape and consequent tissue fibrosis. Further studies are warranted to test VISTA as a novel therapeutic target for the IPF treatment.

CMV exposure drives long-term CD57+ CD4 memory T-cell inflation following allogeneic stem cell transplant.

Donor and recipient cytomegalovirus (CMV) serostatus correlate with transplant-related mortality that is associated with reduced survival following allogeneic stem cell transplant (SCT). Prior epidemiologic studies have suggested that CMV seronegative recipients (R-) receiving a CMV-seropositive graft (D+) experience inferior outcomes compared with other serostatus combinations, an observation that appears independent of viral reactivation. We therefore investigated the hypothesis that prior donor CMV exposure irreversibly modifies immunologic function after SCT. We identified a CD4+/CD57+/CD27- T-cell subset that was differentially expressed between D+ and D- transplants and validated results with 120 patient samples. This T-cell subset represents an average of 2.9% (D-/R-), 18% (D-/R+), 12% (D+/R-), and 19.6% (D+/R+) (P < .0001) of the total CD4+ T-cell compartment and stably persists for at least several years post-SCT. Even in the absence of CMV reactivation post-SCT, D+/R- transplants displayed a significant enrichment of these cells compared with D-/R- transplants (P = .0078). These are effector memory cells (CCR7-/CD45RA+/-) that express T-bet, Eomesodermin, granzyme B, secrete Th1 cytokines, and are enriched in CMV-specific T cells. These cells are associated with decreased T-cell receptor diversity (P < .0001) and reduced proportions of major histocompatibility class (MHC) II expressing classical monocytes (P < .0001), myeloid (P = .024), and plasmacytoid dendritic cells (P = .0014). These data describe a highly expanded CD4+ T-cell population and putative mechanisms by which prior donor or recipient CMV exposure may create a lasting immunologic imprint following SCT, providing a rationale for using D- grafts for R- transplant recipients.

Defining and Understanding Adaptive Resistance in Cancer Immunotherapy.

Despite the unprecedented tumor regression and long-term survival benefit observed with anti-programmed death (PD) [anti-PD-1 or anti-B7-homolog 1 (B7-H1)] therapy in patients with advanced cancers, a large portion of patients do not benefit from such treatment and a fraction of responders relapse. Current efforts to overcome resistance and improve efficacy of anti-PD therapy require a clear understanding of resistance and should precede current avenues using random combinations with available treatment regimens. Here, we categorized three types of resistance, namely target-missing, primary, and acquired resistance. This categorization requires reliable, accurate tissue sampling and appropriate interpretation of results based on the four classifications of tumor immunity in the microenvironment (TIME). We believe that fundamental understanding of these complex tumor-immune interactions and of the cellular and molecular mechanisms underlying these types of true resistance is the key for targeting the right targets in combination with or beyond anti-PD therapy in the future.

Thiophen urea derivatives as a new class of hepatitis C virus entry inhibitors.

To develop unique small-molecule inhibitors of hepatitis C virus (HCV), thiophen urea (TU) derivatives were synthesised and screened for HCV entry inhibitory activities. Among them, seven TU compounds exhibited portent anti-viral activities against genotypes 1/2 (EC50 < 30 nM) and subsequently, they were further investigated; based on the pharmacological, metabolic, pharmacokinetic, and safety profiles, J2H-1701 was selected as the optimised lead compound as an HCV entry inhibitor. J2H-1701 possesses effective multi-genotypic antiviral activity. The docking results suggested the potential interaction of J2H-1701 with the HCV E2 glycoprotein. These results suggest that J2H-1701 can be a potential candidate drug for the development of HCV entry inhibitors.

An Efficient Ionic Liquid-Mediated Extraction and Enrichment of Isoimperatorin from Ostericum koreanum (Max.) Kitagawa.

Ionic liquids (ILs) have attracted significant interest because of their desirable properties. These characteristics have improved their application to overcome the shortcomings of conventional separation techniques for phytochemicals. In this study, several ILs were investigated for their capacity to extract isoimperatorin, a bioactive furanocoumarin, from the roots of Ostericum koreanum. Herein, 1-Butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) was selected as a promising IL for separating isoimperatorin. A central composite design was applied to optimize the extraction conditions. Under the optimal conditions, the yield of isoimperatorin reached 97.17 ± 1.84%. Additionally, the recovery of isoimperatorin from the [Bmim][BF4] solution was successfully achieved (87.73 ± 2.37%) by crystallization using water as an antisolvent. The purity of the isoimperatorin was greatly enhanced, from 0.26 ± 0.28% in the raw material to 26.94 ± 1.26% in the product, in a one-step crystallization process. Namely, an enhancement of approximately 103-folds was reached. The developed approach overcomes the shortcomings of conventional separation methods applied for gaining isoimperatorin by significantly reducing the laboriousness of the process and the consumption of volatile organic solvents. Moreover, the simplicity and effectiveness of the method are assumed to be valuable for producing isoimperatorin-enriched products and for promoting its purification. This work also confirms the efficiency of ILs as a promising material for the separation of phytochemicals.

Determination of SK7324, a new class of hepatitis C virus inhibitor, in rat plasma by UPLC-MS/MS and its application to the pharmacokinetic study of SK7324.

In this study, a sensitive method for quantitation of the unique small-molecule inhibitor of hepatitis C virus SK7324 in rat plasma has been established using ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI/MS/MS). SK7324 and internal standard (tramadol) in plasma sample was extracted using acetonitrile. A centrifuged upper layer was then evaporated and reconstituted with the mobile phase of 0.5% formic acid-acetonitrile (35:65, v/v). The reconstituted samples were injected into a C18 reversed-phase column. Using MS/MS in the multiple reaction monitoring (MRM) mode, SK7324 and tramadol were detected without severe interference from rat plasma matrix. Detection of SK7324 in rat plasma by the UPLC-ESI/MS/MS method was accurate and precise with a quantitation limit of 1.0 ng/mL. The validation, reproducibility, stability, and recovery of the method were evaluated. The method has been successfully applied to pharmacokinetic studies of SK7324 in rat plasma. Pharmacokinetic parameters of SK7324 were evaluated after intravenous (i.v.; at doses of 5 mg/kg) and oral (p.o.; at doses of 10 mg/kg) administration of SK7324 in rats. After p.o. administration (10 mg/kg) of SK7324, F (Fraction absorbed) value was approximately 87.1%.

Pharmacokinetic studies of a novel tubulin inhibitor SK1326 in rat plasma by UPLC-MS/MS.

A sensitive method for quantitation of SK1326 in rat plasma has been established using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI/MS/MS). SK1326 and the internal standard (tramadol) in plasma sample were extracted using acetonitrile. A centrifuged upper layer was then evaporated and reconstituted with a mobile phase of 0.5% formic acid-acetonitrile (35:65, v/v). The reconstituted samples were injected into a C18 reversed-phase column. Using MS/MS in the multiple reaction monitoring mode, SK1326 and tramadol were detected without severe interference from the rat plasma matrix. SK1326 produced a protonated precursor ion ([M + H]+ ) at m/z 432.3 and a corresponding product ion at m/z 114.4. The internal standard produced a protonated precursor ion ([M + H]+ ) at m/z 264.4 and a corresponding product ion at m/z 58.1. Detection of SK1326 in rat plasma by the UPLC-ESI/MS/MS method was accurate and precise with a quantitation limit of 1.0 ng/mL. The validation, reproducibility, stability and recovery of the method were evaluated. The method has been successfully applied to pharmacokinetic studies of SK1326 in rat plasma. The pharmacokinetic parameters of SK1326 were evaluated after intravenous (at a dose of 10 mg/kg) and oral (at a dose of 20 mg/kg) administration of SK1326 in rats. After oral administration (20 mg/kg) of SK1326, the F (fraction absorbed) value was ~77.1%.

Epigenetics in Cancer: A Hematological Perspective.

For several decades, we have known that epigenetic regulation is disrupted in cancer. Recently, an increasing body of data suggests epigenetics might be an intersection of current cancer research trends: next generation sequencing, immunology, metabolomics, and cell aging. The new emphasis on epigenetics is also related to the increasing production of drugs capable of interfering with epigenetic mechanisms and able to trigger clinical responses in even advanced phase patients. In this review, we will use myeloid malignancies as proof of concept examples of how epigenetic mechanisms can trigger or promote oncogenesis. We will also show how epigenetic mechanisms are related to genetic aberrations, and how they affect other systems, like immune response. Finally, we will show how we can try to influence the fate of cancer cells with epigenetic therapy.

Allogeneic Hematopoietic Stem Cell Transplantation Following the Use of Hypomethylating Agents among Patients with Relapsed or Refractory AML: Findings from an International Retrospective Study.

Patients with primary refractory or relapsed acute myeloid leukemia (RR-AML) have very poor prognosis. Due to limited treatment options, some patients are treated with hypomethylating agents (HMAs) due to their tolerability. Little is known about the role of allogeneic hematopoietic stem cell transplantation (HSCT) following HMA therapy in this setting. We retrospectively analyzed an international cohort of 655 RR-AML patients who received HMA therapy to study patterns and outcomes with HSCT. Only 37 patients (5.6%) patients underwent HSCT after HMA therapy. The conditioning regimen was myeloablative in 57% and nonmyeloablative in 43%. Patients received matched unrelated donor, matched sibling, haploidentical and mismatched unrelated HSCT in 56%, 24%, 16% and 4% of cases, respectively. Acute GvHD and chronic GvHD were observed in 40% and 17% of patients. While the median OS for the entire cohort of patients was 15.3 months (95% CI 9.5 - 21.7 months), OS reached 29.7 months (95% CI 7.01 - not-reached) for patients who achieved a complete remission (CR) to HMA and no intervening therapies between HMA therapy and HSCT. Our study suggests that HMA therapy can effectively bridge some patients with RR-AML to HSCT.

Plasma concentration profile of tolterodine and 5-hydroxymethyl tolterodine following transdermal administration of tolterodine in rats.

In this study, the plasma concentration profiles of tolterodine and its active metabolite, 5-hydroxymethyl tolterodine (5-HM tolterodine) were investigated in rats with tolterodine transdermal patches using liquid chromatography-tandem mass spectrometry. The plasma samples were extracted by a liquid-liquid extraction method, with an n-hexane/isopropyl alcohol mixture (9:1, v/v). Tiropramide was used as an internal standard (IS). Chromatographic separation was achieved using a C18 column (2.0 mm × 150 mm, 5 µm), with a mobile phase consisting of 5 mM ammonium acetate in distilled water/acetonitrile (50:50, v/v). The precursor-product ion pairs used for multiple reaction monitoring were m/z 326 → 284 (tolterodine), m/z 342 → 223 (5-HM tolterodine), and m/z 468 → 367 (IS). Subsequently, the plasma concentration levels of tolterodine and 5-HM tolterodine were measured in rat plasma after oral or transdermal administration of tolterodine and the pharmacokinetic parameters were calculated. The Cmax of the patch was less than that of the oral administration but their AUC values were comparable. The resulting data suggested that a transdermal dose of tolterodine 3 times higher (9 mg/12 cm2) could yield comparable efficacy to a 10 mg/kg oral dose in rats. These results would provide useful information on dose optimization of tolterodine transdermal patch for further clinical studies.

Validated high-performance liquid chromatography method for the determination of the inhibitor of cancer cell invasion (E)-N-benzyl-6-[2-(3, 4-dihydroxy benzylidene)hydrazinyl]-N-methylpyridine-3-sulfonamide in rat plasma and its application to pharmacokinetic study.

In this study, a reliable method for the quantitation of (E)-N-benzyl-6-[2-(3, 4-dihydroxy benzylidene)hydrazinyl]-N-methylpyridine-3-sulfonamide (JW-55) in rat plasma was developed and validated using high-performance liquid chromatography. Plasma samples were deproteinized; sildenafil was used as an internal standard. Chromatographic separation was achieved using a reversed-phase C18 column. The mobile phase, 0.02 m ammonium acetate buffer:acetonitrile (48:52, v/v), was run at a flow rate of 1.0 mL/min at room temperature, and the column eluent was monitored using an ultraviolet detector at 280 nm. The retention times of JW-55 and sildenafil were ~5.9 and 7.7 min, respectively. The detection limit of JW-55 in rat plasma was 0.03 µg/mL. Pharmacokinetic parameters of JW-55 were evaluated after intravenous and oral administration of JW-55 (10 mg/kg) in rats. After oral administration, the F value was approximately 73.7%.

MEK inhibitors selectively suppress alloreactivity and graft-versus-host disease in a memory stage-dependent manner.

Immunosuppressive strategies currently used in hematopoietic stem cell transplantation reliably decrease graft-versus-host disease (GVHD) rates, but also impair pathogen-specific immunity. Experimental transplant studies indicate that GVHD-initiating alloreactive T cells reside primarily in naive and central memory T-cell compartments. In contrast, virus-specific T cells comprise a more differentiated memory population. After finding that the rat sarcoma/mitogen-activated protein kinase kinase/extracellular receptor kinase (RAS/MEK/ERK) pathway is preferentially activated in naive and central memory human T cells, we hypothesized that MEK inhibitors would preferentially inhibit alloreactive T cells, while sparing more differentiated virus-specific T cells. Confirming our hypothesis, we found that MEK inhibitors including selumetinib preferentially inhibited cytokine production and alloreactivity mediated by naive and central memory human CD4(+) and CD8(+) T cells while sparing more differentiated T cells specific for the human herpesviruses cytomegalovirus and Epstein-Barr virus. We then demonstrated that short-term posttransplant administration of selumetinib in a major histocompatibility complex major- and minor-mismatched murine model significantly delayed the onset of GVHD-associated mortality without compromising myeloid engraftment, demonstrating the in vivo potential of MEK inhibitors in the setting of hematopoietic stem cell transplantation. These findings demonstrate that targeting memory-dependent differences in T-cell signaling is a potent and selective approach to inhibition of alloreactivity.

Inhibitory effects of harpagoside on TNF-α-induced pro-inflammatory adipokine expression through PPAR-γ activation in 3T3-L1 adipocytes.

Obesity is closely associated with increased production of pro-inflammatory adipokines, including interleukin (IL)-6, plasminogen activator inhibitor (PAI)-1, and adipose-tissue-derived monocyte chemoattractant protein (MCP)-1, which contribute to chronic and low-grade inflammation in adipose tissue. Harpagoside, a major iridoid glycoside present in devil's claw, has been reported to show anti-inflammatory activities by suppression of lipopolysaccharide (LPS)-induced production of inflammatory cytokines in murine macrophages. The present study is aimed to investigate the effects of harpagoside on both tumor necrosis factor (TNF)-α-induced inflammatory adipokine expression and its underlying signaling pathways in differentiated 3T3-L1 cells. Harpagoside significantly inhibited TNF-α-induced mRNA synthesis and protein production of the atherogenic adipokines including IL-6, PAI-1, and MCP-1. Further investigation of the molecular mechanism revealed that pretreatment with harpagoside activated peroxisome proliferator-activated receptor (PPAR)-γ. These findings suggest that the clinical application of medicinal plants which contain harpagoside may lead to a partial prevention of obesity-induced atherosclerosis by attenuating inflammatory responses.

VISTA-mediated immune evasion in cancer.

Over the past decade, V-domain immunoglobulin suppressor of T-cell activation (VISTA) has been established as a negative immune checkpoint molecule. Since the role of VISTA in inhibiting T-cell activation was described, studies have demonstrated other diverse regulatory functions in multiple immune cell populations. Furthermore, its relevance has been identified in human cancers. The role of VISTA in cancer immune evasion has been determined, but its mechanisms in the tumor microenvironment remain to be further elucidated. Understanding its contributions to cancer initiation, progression, and resistance to current treatments will be critical to its utility as a target for novel immunotherapies. Here, we summarize the current understanding of VISTA biology in cancer.

Efficacy and safety of outpatient fludarabine, cyclophosphamide, and rituximab based allogeneic hematopoietic cell transplantation in adults with severe aplastic anemia.

The age effect in severe aplastic anemia (SAA) following allogeneic hematopoietic cell transplantation (HCT) favors the use of reduced intensity conditioning (RIC) regimens in older adults. We implemented a non-myeloablative regimen consisting of fludarabine, cyclophosphamide, and rituximab (FCR) to improve HCT outcomes in SAA. Patients who underwent first HCT for SAA utilizing an FCR regimen between January 2016 and May 2022 were included. Outcomes analyzed included time to engraftment, incidence of graft failure, GVHD, viral reactivation, disease recurrence, and GVHD-free, relapse-free survival (GRFS). Among 24 patients included, median age was 43.5 years (22-62) and a variety of donor types and stem cell sources were represented. At median follow-up of 26.9 months (2.4-72.7), no cases of grade III-IV acute (aGVHD) or severe chronic GVHD (cGVHD) were recorded. Viral reactivation was minimal, and there were no cases of graft failure or PTLD, with 100% disease-free and overall survival at last follow up. The estimate of 1-year GRFS was 86.3% (95% CI: 72.8-100%), with moderate cGVHD accounting for all events. The FCR regimen in SAA was well tolerated, even in older adults, with 100% disease-free survival with low GVHD and infection rates. These encouraging findings should be validated in larger prospective trials.