The burden of acute lymphoid leukemia among adolescents and young adults in the Western Pacific Region: evidence from Global Burden Disease 2019

PURPOSE

Acute lymphoblastic leukemia (ALL) is a type of blood cancer that affects white blood cells. Here, we use data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, to estimate the burden and incidence rate changes in adolescents and young adults (AYA) ALL in the Western Pacific Region and to reveal potential risk factors of incidence- and mortality rates.

METHODS

The GBD 2019 study data was stratified by sex, age, country, and territory. We calculated the Estimated annual percentage changes (estimated APC) in mortality and incidence rates for each of the 25 countries and territories of the western Pacific region from 1990 to 2019.

RESULTS

This study found global AYA ALL incidence rates had increased while the mortality rates had decreased between 1990 and 2019. Moreover, healthcare access and quality (HAQ), and government per capita health spending were identified as country-level risk factors of AYA ALL incidence rates, while HAQ, male education, and sex were identified as mortality rate predictors in 25 Western Pacific Region countries.

CONCLUSION

To address and reduce the burden of incidence and mortality among AYA, various regions around the world, particularly developing countries, could revise their AYA prevention and treatment strategies.

CAR-T Cell Therapy in B-Cell Acute Lymphoblastic Leukemia

Treatment of refractory and relapsed (R/R) B acute lymphoblastic leukemia (B-ALL) is an unmet medical need in both children and adults. Studies carried out in the last two decades have shown that autologous T cells engineered to express a chimeric antigen receptor (CAR-T) represent an effective technique for treating these patients. Antigens expressed on B-cells, such as CD19, CD20, and CD22, represent targets suitable for treating patients with R/R B-ALL. CD19 CAR-T cells induce a high rate (80-90%) of complete remissions in both pediatric and adult R/R B-ALL patients. However, despite this impressive rate of responses, about half of responding patients relapse within 1-2 years after CAR-T cell therapy. Allo-HSCT after CAR-T cell therapy might consolidate the therapeutic efficacy of CAR-T and increase long-term outcomes; however, not all the studies that have adopted allo-HSCT as a consolidative treatment strategy have shown a benefit deriving from transplantation. For B-ALL patients who relapse early after allo-HSCT or those with insufficient T-cell numbers for an autologous approach, using T cells from the original stem cell donor offers the opportunity for the successful generation of CAR-T cells and for an effective therapeutic approach. Finally, recent studies have introduced allogeneic CAR-T cells generated from healthy donors or unmatched, which are opportunely manipulated with gene editing to reduce the risk of immunological incompatibility, with promising therapeutic effects.

P19 a Parthenin Analog Induces Cell Lineage Dependent Apoptotic and Immunomodulatory Signaling in Acute Lymphoid Leukemia Cells

Leukemia is a type of cancer that affects the blood and bone marrow. Acute lymphoid leukaemia, also known as ALL, is regarded as one of the deadliest forms of cancer. Due to the rapid increase in various cancer cases and the development of resistance in cancer cells, it is necessary to identify novel lead molecules with more potent anticancer properties. There is a growing interest in using herbal products/analogs as multi-component agents (as anticancer agents and immunomodulators) for cancer treatment. In the present investigation, an attempt has been made to explore the anticancer and immunomodulatory activity of P19, an analog of parthenin in ALL. P19 was reported to exhibit anticancer efficacy by triggering apoptotic signaling events in human leukaemia HL-60 cells by significant NO production. In contrast to this finding, ROS and NO were not required for P19-mediated apoptosis in Raji cells. The mechanism of action of P19 was observed to be cancer cell lineage dependent. P19 demonstrated very effective anticancer properties against ALL (IC50 3µM). Molecular investigations revealed that P19 induced mitochondrion mediated apoptosis by Bax localization to mitochondria and enhanced cytosolic calcium in the cytoplasm. Further activation of the caspase 3, caspase 8 and PARP cleavage suggested the involvement of the caspase-mediated apoptosis. Anti-proliferative activity revealed the telomerase inhibition and cell cycle arrest in G0/G1 phase after P19 treatment. Immunomodulatory effects of the P19 revealed the enhanced INFɣ and NO production in Jurkat and THP cells. Owing to its antiproliferative and immunomodulatory potential against leukemia cells P19 can further be explored as effective therapeutics against leukemia.

Extracellular expression of Saccharomyces cerevisiae's L-asparaginase II in Pichia pastoris results in novel enzyme with better parameters

L-asparaginase (ASNase) is an efficient inhibitor of tumor development, used in chemotherapy sessions against acute lymphoblastic leukemia (ALL) tumor cells; its use results in 80% complete remission of the disease in treated patients. Saccharomyces cerevisiae's L-asparaginase II (ScASNaseII) has a high potential to substitute bacteria ASNase in patients that developed hypersensitivity, but the endogenous production of it results in hypermannosylated immunogenic enzyme. Here we describe the genetic process to acquire the ScASNaseII expressed in the extracellular medium. Our strategy involved a fusion of mature sequence of protein codified by ASP3 (amino acids 26-362) with the secretion signal sequence of Pichia pastoris acid phosphatase enzyme; in addition, this DNA construction was integrated in P. pastoris Glycoswitch^® strain genome, which has the cellular machinery to express and secrete high quantity of enzymes with humanized glycosylation. Our data show that the DNA construction and strain employed can express extracellular asparaginase with specific activity of 218.2 IU mg^-1. The resultant enzyme is 40% more stable than commercially available Escherichia coli's ASNase (EcASNaseII) when incubated with human serum. In addition, ScASNaseII presents 50% lower cross-reaction with anti-ASNase antibody produced against EcASNaseII when compared with ASNase from Dickeya chrysanthemi.

Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular Consensus on genetically modified cells. II: CAR-T cell therapy for patients with CD19+ acute lymphoblastic leukemia

Chimeric antigen receptor T (CAR-T) cell therapy is a novel therapeutic modality for acute lymphoblastic leukemia (ALL) with robust outcomes in patients with refractory or relapsed disease. At the same time, CAR-T cell therapy is associated with unique and potentially fatal toxicities, such as cytokine release syndrome (CRS) and neurological toxicities (ICANS). This manuscript aims to provide a consensus of specialists in the fields of Hematology Oncology and Cellular Therapy to make recommendations on the current scenario of the use of CAR-T cells in patients with ALL.

Molecular dynamics simulations of human L-asparaginase1: Insights into structural determinants of enzymatic activity

The l-asparaginase enzyme is used in cancer therapy, mainly acute lymphoid leukemia (ALL). Commercial enzymes (EcASNase2) cause adverse reactions during treatment, such as immunogenicity. A human enzyme could be a non-immunogenic substitute. However, no candidate was found showing efficient kinetic properties. HASNase1 is an l-asparaginase that comes from the N-terminal domain of a protein called 60 kDa-lysophospholipase and its 3D structure has not been resolved. HASNase1 is homologous to EcASNase1 and gpASNase1, and this last one has shown efficient kinetic properties. Homology modeling was used to find the 3D structure of hASNase1, so one could submit it to Molecular Dynamics (MD), in order to understand structural differences that lead to different catalytic efficiency compared to EcASNase2 and gpASNase1. The interaction potential between L-Asn and active site residues showed that the substrate can rotate in the site when Region1 is open. Region1 residues sequence favors deformations and movements as shown in MD. Region2-A is linear in gpASNase1, and it features a helix portion in hASNase1, which leaves the Tyr308 position projected to the active site ratifying its role in catalytic efficiency. Analysis of Lys188 orientation and movement showed the effect of positive cooperativity in hASNase1. It was found that the presence of Asn at the allosteric site helps, not only in Region1 stabilization, but also in Lys188 stabilization for the maintenance of the triad. Despite structural similarities in hASNase1, gpASNase1, and EcASNase2, there are differences in structural determinants that, in addition to allosterism, may explain the different kinetic properties.

KMT2A-ARHGEF12, a therapy related fusion with poor prognosis

BACKGROUND

The detection of KMT2A gene rearrangements have an important impact on the prognosis and management of acute leukemias. These alterations most commonly involve reciprocal translocations at specific breakpoint regions within KMT2A. To date, more than 100 translocation partner genes of KMT2A have been identified, with different effects on risk stratification.

METHODS AND RESULTS

We report the case of a mature plasmacytoid dendritic cells proliferation associated with B lymphoblasts harboring a KMT2A-ARHGEF12 fusion. This rare rearrangement, resulting from a cryptic deletion on the long arm of chromosome 11, is located outside the known major and minor breakpoint regions of KMT2A, not reported to date. The review of the few cases of KMT2A-ARHGEF12 reveals the tendency of this deletion to occur in therapy related hematologic neoplasm and confer unfavorable prognosis.

CONCLUSION

This review sheds light into the rare KMT2A-ARHGEF12 fusion in leukemia. Reporting rare chimeras is essential to improve knowledge about the biological mechanism and associated clinical consequences.

Serous retinal detachment as a presenting sign of acute lymphoblastic leukemia: A case report and literature review

Purpose

To describe a unique case of unilateral serous retinal detachment as the presenting sign of B-cell acute lymphoblastic leukemia (ALL).

Observations

A 74 year old woman presented with right eye blurry vision and was found to have an underlying serous retinal detachment, along with cotton wool spots, inner retinal hemorrhages, and retinal pigment epithelial changes throughout her bilateral fundi. Fluorescein angiography demonstrated bilateral vasculitis and ultrasonography revealed asymmetric thickening and enhancement of the affected eyes’ choroid. This prompted a systemic lab workup and results were suspicious for an underlying hematologic malignancy. The patient was admitted to the hospital for bone marrow biopsy confirming B-cell ALL, underwent intensive intravenous and intrathecal chemotherapy, and was discharged one month later. Follow up appointment in the ophthalmology clinic demonstrated functional and anatomic improvement in the serous retinal detachment and choroidal thickening suggestive of infiltration in her right eye.

Conclusions

SRDs are an uncommon ocular manifestation of leukemia, and even less common as a presenting sign of the disease. A comprehensive literature review demonstrated 11 other cases reported worldwide. We present the first such case with additional findings of leukemic retinopathy, optic nerve and choroidal infiltration, and vasculitis, as well as a complete library of ophthalmic imaging from the patient's initial presentation.

Importance

A new diagnosis of serous retinal detachment(s) without any obvious cause should raise suspicion for leukemia and prompt further workup. Early recognition of this hematologic malignancy is crucial for prompt initiation of life-saving therapy.

Urtica dioica agglutinin (a plant lectin) has a caspase-dependent apoptosis induction effect on the acute lymphoblastic leukemia cell line

Urtica dioica agglutinin (UDA) is a very small plant lectin with anti-prostatic activity. In this study, we investigated the effect of UDA on proliferation and apoptosis induction in human acute lymphoid leukemia (ALL) cell lines. The effect of UDA on Jurkat and Raji cell proliferation was examined by MTS assay. Distribution of cell cycle phases was determined by PI staining and apoptosis was examined with annexin V/PI and western blot. Results showed UDA treatment reduced cell proliferation in cells by inducing apoptosis. PI staining was associated with a higher percentage of the cell population in sub G1. Caspase-8 and caspase-9 dependent apoptosis occurred in Jurkat cells. Generally, UDA treatment resulted in cell death in ALL cell lines and induced apoptosis in the T-ALL cell line, Jurkat, through extrinsic and intrinsic pathways. These results may be considered as a guide to working on UDA as an anti-leukemic drug in the future.

Epigenetic drug combination overcomes osteoblast-induced chemoprotection in pediatric acute lymphoid leukemia

Although there has been much progress in the treatment of acute lymphoblastic leukemia (ALL), decreased sensitivity to chemotherapy remains a significant issue. Recent studies have shown how interactions with the bone marrow microenvironment can protect ALL cells from chemotherapy and allow for the persistence of the disease. Epigenetic drugs have been used for the treatment of ALL, but there are no reports on whether these drugs can overcome bone marrow-induced chemoprotection. Our study investigates the ability of the DNA methyltransferase inhibitor azacitidine and the histone deacetylase inhibitor panobinostat to overcome chemoprotective effects mediated by osteoblasts. We show that the combination of azacitidine and panobinostat has a synergistic killing effect and that this combination is more effective than cytarabine in inducing ALL cell death in co-culture with osteoblasts. We also show that this combination can be used to sensitize ALL cells to chemotherapeutics in the presence of osteoblasts. Finally, we demonstrate that these effects can be replicated ex vivo in a number of mouse passaged xenograft lines from both B-ALL and T-ALL patients with varying cytogenetics. Thus, our data provides evidence that azacitidine and panobinostat can successfully overcome osteoblast-induced chemoprotection in vitro and ex vivo in both B-ALL and T-ALL cells.

Patterns of Venous Thromboembolism Prophylaxis During Treatment of Acute Leukemia: Results of a North American Web-Based Survey

BACKGROUND

Venous thromboembolism (VTE) occurs in 2% to 12% of patients with acute leukemia (AL) despite disease- and therapy-associated thrombocytopenia, and it can be associated with significant morbidity and mortality. Because of the few high-quality studies, there are no evidence-based guidelines for VTE prophylaxis in this patient population. We sought to determine the spectrum of practice regarding prevention of VTE in patients with AL during induction and consolidation therapies.

METHODS

We conducted a 19-question Web-based survey directed at North American providers caring for these patients. One hundred fifty-one of 215 responses received were eligible for analysis, with a response rate of 20.9% among physicians who treated leukemias.

RESULTS

Overall, 47% and 45% of providers reported using pharmacologic VTE prophylaxis during induction and consolidation phases, respectively. Approximately 15% of providers did not provide any VTE prophylaxis, while 36% used mechanical methods and ambulation. Among providers who did not recommend pharmacologic prophylaxis, the most commonly cited reasons were the perceived high risk of bleeding (51%), absence of data supporting use (38%), and perceived low risk of VTE (11%).

CONCLUSION

Large, prospective studies are needed to define the safest and most effective approach to VTE prevention in patients with AL.

The NO-modified HIV protease inhibitor as a valuable drug for hematological malignancies: Role of p70S6K

Covalent attachment of NO to the first approved HIV protease inhibitor Saquinavir (Saq-NO) expands the therapeutic potential of the original drug. Apart from retained antiviral activity, the modified drug exerts strong antitumor effects and lower toxicity. In the present study, we have evaluated the sensitivity of different hematological malignancies to Saq-NO. Saq-NO efficiently diminished the viability of Jurkat, Raji, HL-60 and K562 cells. While Jurkat and Raji cells (established from pediatric patients) displayed abrogated proliferative potential, HL-60 and K652 cells (originated from adults) exposed to Saq-NO treatment underwent caspase dependent apoptosis. In addition, similar sensitivity to Saq-NO was observed in mononuclear blood cells obtained from pediatric patients with acute lymphoblastic leukemia (ALL) and adult patients with acute myeloid leukemia (AML). Western blot analysis indicated p70S6 kinase as a possible intracellular target of Saq-NO action. Moreover, the addition of a NO moiety to Lopinavir resulted in improved antitumor potential as compared to the parental compound, suggesting that NO-derived HIV protease inhibitors are a potential new source of anticancer drugs with unique mode of action.

Effects of total body irradiation-based conditioning on allogeneic stem cell transplantation for pediatric acute leukemia: a single-institution study

Purpose

To evaluate the effects of total body irradiation (TBI), as a conditioning regimen prior to allogeneic stem cell transplantation (allo-SCT), in pediatric acute leukemia patients.

Materials and Methods

From January 2001 to December 2011, 28 patients, aged less than 18 years, were treated with TBI-based conditioning for allo-SCT in our institution. Of the 28 patients, 21 patients were diagnosed with acute lymphoblastic leukemia (ALL, 75%) and 7 were diagnosed with acute myeloid leukemia (AML, 25%). TBI was completed 4 days or 1 day before stem cell infusion. Patients underwent radiation therapy with bilateral parallel opposing fields and 6-MV X-rays. The Kaplan-Meier method was used to calculate survival outcomes.

Results

The 2-year event-free survival and overall survival rates were 66% and 56%, respectively (71.4% and 60.0% in AML patients vs. 64.3% and 52.4% in ALL patients, respectively). Treatment related mortality rate were 25%. Acute and chronic graft-versus-host disease was a major complication; other complications included endocrine dysfunction and pulmonary complications. Common complications from TBI were nausea (89%) and cataracts (7.1%).

Conclusion

The efficacy and toxicity data in this study of TBI-based conditioning to pediatric acute leukemia patients were comparable with previous studies. However, clinicians need to focus on the acute and chronic complications related to allo-SCT.

Stathmin 1 is involved in the highly proliferative phenotype of high-risk myelodysplastic syndromes and acute leukemia cells

Stathmin 1 is an important cytoplasmic microtubule-destabilizing protein that plays critical roles in proliferation and accurate chromosome segregation through regulation of microtubule dynamics. High levels of Stathmin 1 expression have been reported in leukemia and solid tumors. However, Stathmin 1 has not been studied in myelodysplastic syndrome cells. We, herein, report that significantly higher Stathmin 1 levels were observed in proliferating hematopoietic cells, in high-risk MDS and acute leukemia cells. In addition, Stathmin 1 silencing in U937 and Namalwa leukemia cells reduced cell proliferation and clonogenicity. Our data suggest that Stathmin 1 expression may be related to the highly proliferative phenotype of hematopoietic cells and add new insights into the participation of Stathmin 1 in hematological malignancies.

Acute lymphoid leukemia presenting with superior vena cava syndrome

When superior vena cava (SVC) compress or obstructed by internal or external pressure, we encounter to SVC syndrome. The cause of this compression is malignant or benign. Although the widespread use of permanent central venous access catheters coupled with the improved success of chemotherapy has increased the incidence of SVC syndrome not caused by direct tumor infiltration (non-malignant SVC syndrome) but SVC syndrome may be a sign of advanced malignancy. In this report, we present a 30-year-old man with lymphoma that present with SVC syndrome at presentation. With chemotherapy, patient was recovered from signs and symptoms.