Clofarabine Preconditioning followed by Allogeneic Transplant Using TBI and Post-Transplant Cyclophosphamide for Relapsed Refractory Leukemia.

Acute myeloid leukemia patients with induction failure or relapsed refractory disease have minimal chance of achieving remission with subsequent treatments. Several trials have shown the feasibility of clofarabine-based conditioning in allogeneic stem cell transplants (allo-HSCT) for non-remission AML patients. Pre-transplant conditioning with clofarabine followed by reduced-intensity allo-HSCT has also demonstrated a potential benefit in those patients with human leukocyte antigen (HLA)-identical donors, but it is not commonly used in haploidentical and mismatched transplants. In this case report, we describe our experience of seven cases of non-remission AML who received clofarabine preconditioning followed by an allo-HSCT with PTCy. The 2-year overall survival and disease-free survival was 83.3% (95% confidence interval (CI): 27.3-97.9%) and 85.7% (95% CI: 33.4-97.9%). Median days of neutrophil and platelet recovery were 16 (range of 13-23) and 28 (range of 17-75), respectively. The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) at day 100 and chronic GVHD at 1-year showed 28.6% (95% CI: 8-74.2%) and 28.6% (95% CI: 3-63.9%), respectively. The two-year relapse rate was 14.3% (95% CI: 2.14-66.6%). One-year GVHD-free relapse-free survival (GFRS) at 1-year was 71.4% (95% CI: 25.8-92%). Our patients showed successful outcomes with clofarabine preconditioning to reduce the leukemic burden at the pre-transplant period followed by PTCy to reduce GVHD resulting in lower relapsed rate and better GFRS in these patients.

Advancing the understanding of venetoclax in t(11;14)-positive multiple myeloma: a comprehensive review of clinical evidence and future prospects.

Venetoclax is a selective inhibitor of the anti-apoptotic protein B-cell lymphoma 2 (BCL2), as a targeted therapy for multiple myeloma (MM) patients. It was initially approved by the United States Food and Drug Administration for the treatment of chronic lymphocytic leukemia in April 2016 and later for acute myeloid leukemia in October 2020. However, venetoclax is used as an off-label in a subset group of relapsed and refractory multiple myeloma (RRMM) patients with the presence of translocation t(11;14). Preclinical and clinical studies have highlighted the potential of venetoclax in the management of MM patients, with a specific focus on t(11;14) as a predictive biomarker for initiating venetoclax-based treatment. Later, several studies in RRMM patients that used venetoclax in combination with dexamethasone or/and proteasome inhibitors have shown promising results, in which management guidelines have included venetoclax as one of the options to treat MM patients. Hence, this review focuses on the use of venetoclax in RRMM, clinical efficacy, safety, dosing strategies, and predictive biomarkers for initiating venetoclax. Additionally, we discuss ongoing studies that are investigating different combination of venetoclax regimens in MM patients.

The potential role of the thymus in immunotherapies for acute myeloid leukemia.

Understanding the factors which shape T-lymphocyte immunity is critical for the development and application of future immunotherapeutic strategies in treating hematological malignancies. The thymus, a specialized central lymphoid organ, plays important roles in generating a diverse T lymphocyte repertoire during the infantile and juvenile stages of humans. However, age-associated thymic involution and diseases or treatment associated injury result in a decline in its continuous role in the maintenance of T cell-mediated anti-tumor/virus immunity. Acute myeloid leukemia (AML) is an aggressive hematologic malignancy that mainly affects older adults, and the disease's progression is known to consist of an impaired immune surveillance including a reduction in naïve T cell output, a restriction in T cell receptor repertoire, and an increase in frequencies of regulatory T cells. As one of the most successful immunotherapies thus far developed for malignancy, T-cell-based adoptive cell therapies could be essential for the development of a durable effective treatment to eliminate residue leukemic cells (blasts) and prevent AML relapse. Thus, a detailed cellular and molecular landscape of how the adult thymus functions within the context of the AML microenvironment will provide new insights into both the immune-related pathogenesis and the regeneration of a functional immune system against leukemia in AML patients. Herein, we review the available evidence supporting the potential correlation between thymic dysfunction and T-lymphocyte impairment with the ontogeny of AML (II-VI). We then discuss how the thymus could impact current and future therapeutic approaches in AML (VII). Finally, we review various strategies to rejuvenate thymic function to improve the precision and efficacy of cancer immunotherapy (VIII).

Impact of hematopoietic stem cell transplantation in glycogen storage disease type Ib: A single-subject research design using 13C-glucose breath test.

Background: Glycogen storage disease type Ib (GSD Ib) is an autosomal recessively inherited deficiency of the glucose-6-phosphate translocase (G6PT). Clinical features include a combination of a metabolic phenotype (fasting hypoglycemia, lactic acidosis, hepatomegaly) and a hematologic phenotype with neutropenia and neutrophil dysfunction. Dietary treatment involves provision of starches such as uncooked cornstarch (UCCS) and Glycosade® to provide prolonged enteral supply of glucose. Granulocyte colony-stimulating factor (G-CSF) is the treatment of choice for neutropenia. Because long-term stimulation of hematopoiesis with G-CSF causes serious complications such as splenomegaly, hypersplenism, and osteopenia; hematopoietic stem cell transplantation (HSCT) has been considered in some patients with GSD Ib to correct neutropenia and avoid G-CSF related adverse effects. Whether HSCT also has an effect on the metabolic phenotype and utilization of carbohydrate sources has not been determined. Objective: Our objective was to measure the utilization of starch in a patient with GSD Ib before and after HSCT using the minimally invasive 13C-glucose breath test (13C-GBT). Design: A case of GSD Ib (18y; female) underwent 13C-GBT four times: UCCS (pre-HSCT), UCCS (3, 5 months post-HSCT) and Glycosade® (6 months post-HSCT) with a dose of 80 g administered via nasogastric tube after a 4 h fast according to our patient's fasting tolerance. Breath samples were collected at baseline and every 30 min for 240 min. Rate of CO2 production was measured at 120 min using indirect calorimetry. Finger-prick blood glucose was measured using a glucometer hourly to test hypoglycemia (glucose <4 mmol/L). Biochemical and clinical data were obtained from the medical records as a post-hoc chart review. Results: UCCS utilization was significantly higher in GSD Ib pre-HSCT, which reduced and stabilized 5 months post-HSCT. UCCS and Glycosade® utilizations were low and not different at 5 and 6 months post-HSCT. Blood glucose concentrations were not significantly different at any time point. Conclusions: Findings show that HSCT stabilized UCCS utilization, as reflected by lower and stable glucose oxidation. The results also illustrate the application of 13C-GBT to examine glucose metabolism in response to various carbohydrate sources after other treatment modalities like HSCT in GSD Ib.

N1-methyladenosine modification in cancer biology: Current status and future perspectives.

Post-transcriptional modifications in RNAs regulate their biological behaviors and functions. N1-methyladenosine (m1A), which is dynamically regulated by writers, erasers and readers, has been found as a reversible modification in tRNA, mRNA, rRNA and long non-coding RNA (lncRNA). m1A modification has impacts on the RNA processing, structure and functions of targets. Increasing studies reveal the critical roles of m1A modification and its regulators in tumorigenesis. Due to the positive relevance between m1A and cancer development, targeting m1A modification and m1A-related regulators has been of attention. In this review, we summarized the current understanding of m1A in RNAs, covering the modulation of m1A modification in cancer biology, as well as the possibility of targeting m1A modification as a potential target for cancer diagnosis and therapy.

Validation of atovaquone plasma levels by liquid chromatography-tandem mass spectrometry for therapeutic drug monitoring in pediatric patients.

Background: Atovaquone has traditionally been used as an antiparasitic and antifungal agent, but recent studies have shown its potential as an anticancer agent. The high variability in atovaquone bioavailability highlights the need for therapeutic drug monitoring, especially in pediatric patients. The goal of our study was to develop and validate the performance of an assay to quantify atovaquone plasma concentrations collected from pediatric cancer patients using LC-MS/MS. Methods: Atovaquone was extracted from a 10 µL volume of K2-EDTA human plasma using a solution consisting of ACN: EtOH: DMF (8:1:1 v:v:v), separated using reverse-phase chromatography, and detected using a SCIEX 5500 QTrap MS system. LC-MS/MS assay performance was evaluated for precision, accuracy, carryover, sensitivity, specificity, linearity, and interferences. Results: Atovaquone and its deuterated internal standard were analyzed using a gradient chromatographic method that had an overall cycle-time of 7.4 min per injection, and retention times of 4.3 min. Atovaquone was measured over a dynamic concentration range of 0.63 - 80 µM with a deviation within ≤ ± 5.1 % of the target value. Intra- and inter-assay precision were ≤ 2.7 % and ≤ 8.4 %, respectively. Dilutional, carryover, and interference studies were also within acceptable limits. Conclusions: Our studies have shown that our LC-MS/MS-based method is both reliable and robust for the quantification of plasma atovaquone concentrations and can be used to determine the effective dose of atovaquone for pediatric patients treated for AML.

A rare combination of acute myeloid leukemia with Vit B12 deficiency: Case report.

Introduction and importance: Acute myeloid leukemia (AML) is a malignant disease with several risk factors from hematologic disorders, which almost presents as anemia. AML is characterized by the presence of myeloblast in the blood picture. On the other hand, macrocytic anemia characterized by the presence of megaloblastic marrow morphology. We are presenting a rare case of combined Acute myeloid leukemia with macrocytic anemia. Case presentation: A 45 years old married woman was admitted for hyperthermia, dysuria, and chills. She had suffered from general malaise, weakness, and myalgia for two months. In her laboratories, the peripheral blood sample showed: HGB 26.1% (5.6 g/dL), RBCs 1.4 M/µL, WBC 13.3 K/µL. The blood smear showed megaloblastic features, so she was diagnosed with macrocytic anemia, and the treatment was blood transfusion, antibiotics, and muscular Vit B12. After one month, the peripheral blood sample showed an elevation of WBC, the bone marrow aspiration showed myeloblast infiltration represents 60% of the total events, and the flow cytometry for the bone marrow aspiration agrees with Acute Myeloblastic leukemia with Maturation M2 (AML-M2). Clinical discussion: The incidence of macrocytic anemia and leukemia in one patient is infrequent, case reports give scarce information concerning a potential increased occurrence of leukemia in patients putting up with macrocytic anemia. Several theories discussed the reasons for the association of the two conditions. Conclusion: we need more research on similar cases to identify the pathological mechanism.

FEV Maintains Homing and Expansion by Activating ITGA4 Transcription in Primary and Relapsed AML.

Acute myeloid leukemia (AML) is an aggressive hematological malignancy that recurs in approximately 50% of cases. Elevated homing and uncontrolled expansion are characteristics of AML cells. Here, we identified that Fifth Ewing Variant (FEV) regulates the homing and expansion of AML cells. We found that FEV was re-expressed in 30% of primary AML samples and in almost all relapsed AML samples, and FEV expression levels were significantly higher in relapsed samples compared to primary samples. Interference of FEV expression in AML cell lines delayed leukemic progression and suppressed homing and proliferation. Moreover, FEV directly activated integrin subunit alpha 4 (ITGA4) transcription in a dose-dependent manner. Inhibition of integrin α4 activity with natalizumab (NZM) reduced the migration and colony-forming abilities of blasts and leukemic-initiating cells (LICs) in both primary and relapsed AML. Thus, our study suggested that FEV maintains the homing and expansion of AML cells by activating ITGA4 transcription and that targeting ITGA4 inhibits the colony-forming and migration capacities of blasts and LICs. Thus, these findings suggested that the FEV-ITGA4 axis may be a therapeutic target for both primary and relapsed AML.

Bacillus Cereus bacteremia complicated by brain abscess in a severely immunocompromised patient: Addressing importance of early recognition and challenges in diagnosis.

Bacillus cereus (B. cereus) is a known cause of a food poisoning in the general population. However, it can cause life-threatening sepsis and shock in severely immunocompromised patients with hematologic malignancies, which frequently lead to central nervous system (CNS) infections associated with high mortality and morbidity. In this case report, we describe a patient with a newly diagnosed acute myeloid leukemia that underwent induction chemotherapy and developed B. cereus infection that was associated with septic shock and brain abscesses. Definitive diagnosis of multiple brain abscesses was not manifested with routine microbiological investigation but required the use of 16S ribosomal (rRNA) gene polymerase chain reaction (PCR) sequencing of the resected brain lesion. The patient was eventually treated with 8-week course of intravenous vancomycin and high-dose ciprofloxacin which led to a full recovery. This report highlights the significant risk posed by B. cereus infection in neutropenic patients, the use of 16S rRNA PCR sequencing test for definitive diagnosis and use of combination therapy for successful treatment of B. Cereus CNS infection.

Cardiovascular Disease Among Patients With AML and CHIP-Related Mutations.

Background: Clonal hematopoiesis of indeterminate potential (CHIP) is a novel cardiovascular disease (CVD) risk factor in individuals without acute myeloid leukemia (AML). Objectives: The aim of this study was to examine the association between mutations associated with CHIP (CHIP-related mutations) identified in patients at AML diagnosis and the risk for cardiovascular events (CVEs). Methods: This was a retrospective cohort study of 623 patients with AML treated between 2015 and 2018 who underwent DNA analysis. Cause-specific hazard regression models were used to study the associations between pathogenic mutations in common CHIP-related genes (DNMT3A, TET2, ASXL1, JAK2, TP53, SRSF2, and SF3B1) and the rate of CVEs (heart failure hospitalization, acute coronary syndrome, coronary artery revascularization, ischemic stroke, venous thromboembolism, and CVD death) and between CVE development and all-cause mortality. Results: Patients were 64.6 ± 15.3 years of age, 265 (42.5%) were women, and 63% had at least 1 CHIP-related mutation. Those with CHIP-related mutations were older (69.2 ± 12.3 vs 56.6 ± 16.6 years; P < 0.001) and had a greater prevalence of CVD risk factors and CVD history. In adjusted analysis, the presence of any CHIP-related mutation was associated with a higher rate of CVEs (HR: 1.74; 95% CI: 1.03-2.93; P = 0.037) among intensively treated patients (anthracycline based) but not the whole cohort (HR: 1.26; 95% CI: 0.81-1.97; P = 0.31). TP53 (HR: 4.18; 95% CI: 2.07-8.47; P < 0.001) and ASXL1 (HR: 2.37; 95% CI: 1.21-4.63; P = 0.012) mutations were associated with CVEs among intensively treated patients. Interval development of CVEs was associated with all-cause mortality (HR: 1.99; 95% CI: 1.45-2.73; P < 0.001). Conclusions: Among patients with AML treated with intensive chemotherapy, mutations in CHIP-related genes were associated with an increased risk for developing incident CVEs after AML diagnosis.

Clinical usefulness of 2-hydroxyglutarate as a biomarker in IDH-mutant chondrosarcoma.

Background: Chondrosarcoma is a common form of malignant bone tumor with limited treatment options. Approximately half of chondrosarcomas harbor gain-of-function mutations in isocitrate dehydrogenase (IDH), and mutant IDH produces 2-hydroxyglutarate (2-HG), which is an oncometabolite that contributes to malignant transformation. Therefore, inhibiting 2-HG production is a novel and promising treatment for advanced chondrosarcoma. 2-HG is also expected to be a useful biomarker for the diagnosis and treatment of IDH-mutant tumors. However, few studies have confirmed this using chondrosarcoma clinical specimens. Non-invasive monitoring of 2-HG levels is useful to infer that mutant IDH inhibitors reach therapeutic targets and to confirm their therapeutic efficacy in clinical practice. Methods: To evaluate the clinical utility of 2-HG as a surrogate biomarker for diagnosis and therapeutic efficacy, we measured intra-tumor and serum levels of 2-HG using frozen tissues and peripheral blood from patients with chondrosarcoma. We also developed a non-invasive method to detect intra-tumor 2-HG signals in vivo using magnetic resonance spectroscopy (MRS). Results: Both intratumoral and serum 2-HG levels were significantly elevated in IDH-mutant tumors, and these levels correlated with decreased survival. Furthermore, we detected intratumoral 2-HG peaks using MR spectroscopy in a xenograft model of IDH-mutant chondrosarcoma, and observed that 2-HG peak signals disappeared after administering an inhibitor of mutant IDH1. Conclusions: Our findings suggest that both intratumoral and serum 2-HG levels represent potentially useful biomarkers for IDH-mutant tumors and that the 2-HG signal in MR spectra has potential value as a non-invasive biomarker. Taken together, these findings may positively impact the clinical development of mutant IDH inhibitors for the treatment of advanced chondrosarcoma.

Isolated Myeloid Sarcoma and Intracardiac Thrombus Resulting in Superior Mediastinal Syndrome.

Superior mediastinal syndrome (SMS) is a relatively common emergency in the practice of Pediatric Oncology. It typically results from the compression of large airways and superior vena cava by a swiftly growing mass. T-lineage acute lymphoblastic leukemia or lymphoma, neuroblastoma, and germ cell tumor are the common etiologies of SMS in children. Occasionally, SMS can be an unexpected presentation of less common childhood cancers and a surprise for the diagnostic and treating teams. The present paper reports the diagnostic and therapeutic challenge of managing a 9-y-old boy with SMS resulting from mediastinal myeloid sarcoma. The presence of a sizeable intracardiac thrombus, in addition, contributed to the SMS. The initial pleural fluid cytology and image-guided fine-needle aspiration cytology of the mediastinal mass were nondiagnostic. A thoracotomy was subsequently performed to debulk the tumor for symptomatic relief and obtain tissue for diagnosis.

Impact of Perioperative Absolute Neutrophil Count on Central Line-Associated Bloodstream Infection in Children With Acute Lymphoblastic and Myeloid Leukemia.

BACKGROUND: There is lack of evidence concerning safety of placement of tunneled central venous catheters (TCVCs) in neutropenic children with acute leukemias. Here, we evaluate the impact of absolute neutrophil count (ANC) at the time of TCVC placement on development of central line-associated bloodstream infections (CLABSI) in children with lymphoblastic (ALL) or myeloid leukemia (AML). MATERIALS AND METHODS: A retrospective observational study of children undergoing TCVC placement at a tertiary referral hospital between January 2000 and December 2019 was performed. Traditional and competing-risks regression models were used to estimate the effect of perioperative ANC on development of CLABSI. RESULTS: A total of 350 children (median age 6.4 [IQR: 3.1-10.9] years) underwent 498 consecutive TCVC implantations in neutropenic (n = 172, 34.5%) and non-neutropenic conditions (n = 326, 65.5%). The median length of observation per TCVC was 217.1 (IQR: 116.1-260.5) days with a total of 99,681 catheter days (CD). There were no differences in early (within first 30 days after TCVC placement) and overall CLABSI rates between neutropenic and non-neutropenic patients (HR 1.250, p = 0.502; HR 1.633, p = 0.143). We identified female sex (HR 2.640, p = 0.006) and the use of TCVC for treatment of relapsed leukemia (HR 4.347, p < 0.0001) as risk factors for early CLABSI and the use of double-lumen catheters (HR 2.607, p = 0.003) and use of TCVCs during leukemia relapse (HR 2.004, p = 0.005) for overall study period. CONCLUSION: The placement of TCVC in children with neutropenia undergoing anticancer therapy for acute leukemia is safe and not associated with an elevated rate of CLABSI.

The first case of Janibacter hoylei bacteremia in an adult.

The Janibacter species are Gram positive, coryneform bacteria that belong to the Actinobacteria phylum and have been linked to bacteremia in immunocompromised children. We present the first documented adult case of Janibacter hoylei bacteremia. The patient was a 52-year-old woman with a history of recurrent Clostridioides difficile infection, sinus tachycardia and high-risk AML who had been admitted one month prior to presentation for matched unrelated donor hematopoietic stem cell transplant with reduced intensity fludarabine-melphalan. Thirty days post-transplant, the infectious disease team was consulted because blood cultures grew Janibacter hoylei, from one of two blood cultures It took nine days to identify the species. She was treated with linezolid and imipenem. Janibacter are rarely implicated in human pathology, and therein, usually identified in the context of malignancy and relative immunosuppression. J. hoylei was only previously reported from the bloodstream of a previously healthy 8-week-old infant without underlying medical conditions. Antimicrobial susceptibility testing is challenging as only in vitro susceptibility testing of Janibacter terrae has been reported. Given these challenges, it is our hope to illustrate the clinical approach to diagnosis as well as subsequent recommendations for treatment in a particularly challenging case of bacteremia in an AML patient.

Recent developments in the medicinal chemistry of single boron atom-containing compounds.

Various boron-containing drugs have been approved for clinical use over the past two decades, and more are currently in clinical trials. The increasing interest in boron-containing compounds is due to their unique binding properties to biological targets; for example, boron substitution can be used to modulate biological activity, pharmacokinetic properties, and drug resistance. In this perspective, we aim to comprehensively review the current status of boron compounds in drug discovery, focusing especially on progress from 2015 to December 2020. We classify these compounds into groups showing anticancer, antibacterial, antiviral, antiparasitic and other activities, and discuss the biological targets associated with each activity, as well as potential future developments.

High expression levels and the C3435T SNP of the ABCB1 gene are associated with lower survival in adult patients with acute myeloblastic leukemia in Mexico City.

BACKGROUND: Acute myeloid leukemia (AML) is a heterogeneous hematologic malignancy characterized by different genetic alterations that cause changes in the normal mechanisms of differentiation, which are associated with chemoresistance. The ABCB1 gene is part of a family of ATP-binding cassette (ABC) transporter genes involved in the progression of various types of cancer. The following work aimed to evaluate the expression levels of the ABCB1 gene and the C3435T SNP with the response to first-line treatment and survival in patients with AML. METHODS: In total 135 samples were taken to isolate total RNA and DNA at the beginning of the treatment. Expression analysis by RT-qPCR and SNP C3435T assessment method were performed for real-time Polymerase chain reaction (qPCR). RESULTS: The expression levels impact on the survival of patients with AML compared to low or absent levels; the CC genotype was found in 22.9%, the CT genotype was found in 47.4%, and the TT genotype was found in 29.6%, the presence of the C3435T SNP, the TT genotype also impacts with a lower survival compared to CT and CC genotypes. In addition, it was shown that the dominant model significantly impacts survival. CONCLUSION: In conclusion, we have found that the overexpression of the ABCB1 gene, as well as the presence of the TT genotype of the C3435T SNP, contributes to a worse prognosis in AML.

A Journey Across Oceans With a Heavy Heart: Rare Presentation of a Pediatric Malignancy.

Myeloid sarcoma, due to extramedullary deposition of myeloblasts, is one of the rare presentations in acute myeloid leukemia. We present an extremely rare case of a 5-year-old boy with cardiac myeloid sarcoma. Noninvasive mode of diagnosis, timely initiation of chemotherapy and meticulous supportive care are the keys to successful outcome. (Level of Difficulty: Intermediate.).

Preclinical efficacy against acute myeloid leukaemia of SH1573, a novel mutant IDH2 inhibitor approved for clinical trials in China.

Acute myeloid leukaemia (AML) is the most common form of acute leukaemia in adults, with increasing incidence with age and a generally poor prognosis. Almost 20% of AML patients express mutant isocitrate dehydrogenase 2 (mIDH2), which leads to the accumulation of the carcinogenic metabolite 2-hydroxyglutarate (2-HG), resulting in poor prognosis. Thus, global institutions have been working to develop mIDH2 inhibitors. SH1573 is a novel mIDH2 inhibitor that we independently designed and synthesised. We have conducted a comprehensive study on its pharmacodynamics, pharmacokinetics and safety. First, SH1573 exhibited a strong selective inhibition of mIDH2 R140Q protein, which could effectively reduce the production of 2-HG in cell lines, serum and tumors of an animal model. It could also promote the differentiation of mutant AML cell lines and granulocytes in PDX models. Then, it was confirmed that SH1573 possessed characteristics of high bioavailability, good metabolic stability and wide tissue distribution. Finally, toxicological data showed that SH1573 had no effects on the respiratory system, cardiovascular system and nervous system, and was genetically safe. This research successfully promoted the approval of SH1573 for clinical trials (CTR20200247). All experiments demonstrated that, as a potential drug against mIDH2 R140Q acute myeloid leukaemia, SH1573 was effective and safe.