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It has been shown that endothelial cell (EC) activation and tissue factor (TF) upregulation in EC and monocytes by antiphospholipid antibodies (aPL Abs) leads to a prothrombotic state and involves translocation of nuclear factor-kappa B (NF-kappaB). Here we examined the effects of an NF-kappaB inhibitor on aPL-induced thrombosis, TF activity, and EC in vivo. We treated CD1 mice with IgG from a patient with antiphospholipid syndrome (IgG-APS) or with control IgG (IgG-NHS). The adhesion of leukocytes (number of white blood cells) to EC in cremaster muscle (as an indication of EC activation) as well as the size of an induced thrombus in the femoral vein of the mice were examined. Some mice in each group were infused with 10 microM MG132 (an inhibitor of NF-kappaB). TF activity was determined using a chromogenic assay in homogenates of carotid arteries and in peritoneal cells of mice. In vivo, IgG-APS increased significantly the number of white blood cells adhering to ECs (4.7 +/- 2.2) when compared to control mice (1.5 +/- 0.8), and these effects were significantly reduced when mice were pretreated with MG132 (0.8 +/- 0.2). IgG-APS increased significantly the thrombus size and MG132 inhibited that effect (93%). Treatment of the mice with IgG-APS also induced significantly increased TF function in peritoneal cells and in homogenates of carotid arteries. Pretreatment of the mice with MG132 abrogated those effects significantly. Mice injected with IgG-APS or with IgM-APS with or without the inhibitor had medium-high titers of anticardiolipin antibodies in serum at the time of the surgical procedures. The data show that prothrombotic and proinflammatory properties of IgG-APS and IgM-APS are downregulated in vivo by an NF-kappaB inhibitor. These findings may be important in designing new modalities of targeted therapies to treat thrombosis in patients with APS.

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Purpose of Review Acute myeloid leukemia (AML) is a costly disease, and its impact is greater in developing countries (DC). We will review the current concept of what are DC, compare the differences in the epidemiology and economic burden of this disease between developed and DC, and finally, analyze the barriers and possible solutions that DC should implement to achieve better results. Recent Findings DC is a frequently misunderstood name. The way we use to measure human development is changing, and multidimension metrics better define what are DC. With this in mind, we show the differences in the AML epidemiology and the impact of economic burden in DC. We analyze the barriers to access therapy from a clinician point of view, to show that most DC shared similar challenges but with a diverse healthcare structure. Finally, we provide several possible solutions for a more integrated and timely treatment that allows better results not only in terms of survival but with a better quality of life. Summary The economic burden of AML treatment in DC is high, and the results are poor. It is crucial to face this challenge and propose new treatment approaches to achieve better results.

Acute lymphoblastic leukemia (ALL) is a hematologic malignancy characterized by the clonal expansion of hematopoietic lymphoid progenitors. With new target therapies, the survival of adults with ALL has improved in the past few decades. Unfortunately, there are no large ALL patient series in many Latin American countries. Data from the Acute Leukemia Workgroup that includes five Mexico City referral centers were used. Survival was estimated for adult patients with ALL during 2009–2015. In total, 559 adults with ALL were included. The median age was 28 years; 67% were classified into the adolescent and young adult group. Cytogenetic information was available in 54.5% of cases. Of the 305 analyzed cases, most had a normal caryotype (70.5%) and Philadelphia‐positive was present in 16.7%. The most commonly used treatment regimen was hyper‐CVAD. In approximately 20% of cases, there was considerable delay in the administration of chemotherapy. Primarily refractory cases accounted for 13.1% of patients. At the time of analysis, 26.7% of cases had survived. The 3‐year overall survival was 22.1%. The main cause of death was disease progression in 228 (55.6%). Clinical and public health strategies are needed to improve diagnosis, treatment and survivorship care for adult with ALL. This multicentric report represents the largest series in Mexico of adult ALL patients in which a survival analysis and risk identification were obtained.

Background: Venous thromboembolism (VTE) is a common disease in Latin American settings. Implementing international guidelinn Aes in Latimerican settings requires additional considerations. Objective: The purpose of our study was to provide evidence-based guidelines about managing VTE for Latin American patients, clinicians, and decision makers. Methods: We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE)-ADOLOPMENT method to adapt recommendations from 2 American Society of Hematology (ASH) VTE guidelines (Treatment of VTE and Anticoagulation Therapy). ASH and local hematology societies formed a guideline panel comprised of medical professionals from 10 countries in Latin America. Panelists prioritized 18 questions relevant for the Latin American context. A knowledge synthesis team updated evidence reviews of health effects conducted for the original ASH guidelines and summarized information about factors specific to the Latin American context (ie, values and preferences, resources, accessibility, feasibility, and impact on health equity). Results: The panel agreed on 17 recommendations. Compared with the original guideline, 4 recommendations changed direction and 1 changed strength. Conclusions: This guideline adolopment project highlighted the importance of contextualization of recommendations suggested by the changes to the original recommendations. The panel also identified 2 implementation priorities for the region: expanding the availability of home treatment and increasing the availability of direct oral anticoagulants (DOACs). The guideline panel made a conditional recommendation in favor of home treatment for individuals with deep venous thrombosis and a conditional recommendation for either home or hospital treatment for individuals with pulmonary embolism. In addition, a conditional recommendation was made in favor of DOACs over vitamin K antagonists for several populations.

Background: From 2017 to 2020, the American Society of Hematology (ASH) collaborated with 12 hematology societies in Latin America to adapt the ASH guidelines on venous thromboembolism (VTE). Objective: To describe the methods used to adapt the ASH guidelines on venous thromboembolism. Methods: Each society nominated 1 individual to serve on the guideline panel. The work of the panel was facilitated by the 2 methodologists. The methods team selected 4 of the original VTE guidelines for a first round. To select the most relevant questions, a 2-step prioritization process was conducted through an on-line survey and then through in-person discussion. During an in-person meeting in Rio de Janeiro, Brazil, from 23 April through 26 April 2018, the panel developed recommendations using the ADOLOPMENT approach. Evidence about health effects from the original guidelines was reused, but important data about resource use, accessibility, feasibility, and impact in health equity were added. Results: In the guideline accompanying this paper, Latin American panelists selected 17 questions from an original pool of 49. Of the 17 questions addressed, substantial changes were introduced for 5 recommendations, and remarks were added or modified for 12 recommendations. Conclusions: By using the evidence from an international guideline, a significant amount of work and time were saved; by adding regional evidence, the final recommendations were tailored to the Latin American context. This experience offers an alternative to develop guidelines relevant to local contexts through a global collaboration.

Background: Mexico and Central America have a high incidence of acute lymphoblastic leukemia (ALL) in adolescents and young adults (AYA). Chemotherapy with Hyper-CVAD has been widely used with poor outcomes, with a 3-year overall survival (OS) of 25.7% in this group of age. In low-and middle-income countries (LMIC), limitations in supportive care such as low access to neutrophil stimulant agents, antifungal prophylaxis and limited intensive care access, may increase treatment-related mortality. On the other hand, reports suggest that specific high-risk subgroups may be more frequent in Hispanic patients from Mexico and Central America. We hypothesize that the use of a less-myeloablative regimen, based on L-asparaginase could overcome the bad outcomes previously reported. Methods We modified the original CALGB 10403 based on local drug-access. We include patients with newly diagnosed Philadelphia-negative B- or T-cell ALL between 14-49 years from 4 centers in Mexico and one in Guatemala. We modified the regimen as following: replaced pegaspargase by E. Coli asparaginase, thioguanine by 6-mercapatopurine and incorporate rituximab 375mg/m2 for 6 doses in CD20 positive patients. After the first interim analysis (October 2019), we replaced the prednisone by dexamethasone during induction. Minimal residual disease (MRD) was assessed by flow cytometry after induction and after first consolidation. We considered high-risk karyotype if MLL-rearrangements, complex or hypodiploid and high-white blood cell count (WBC) if >30 x10 3/mcL for B-ALL or >100 x10 3/mcL for T-ALL. The main objective was to evaluate OS and as secondary objectives to evaluate complete response (CR) rate, relapse-free survival (RFS) and to assess the safety of this regimen. Results From January 2017 to December 2020, 95 patients have been enrolled with a median age of 23 years (range 14-49). One third (34.6%) had overweight and 11.7% were obese. The majority (92.6%) had a B-cell ALL and a normal karyotype (81.2%). The median WBC was 18.4 x10 3/mcL (0.2-427.7) and 40.9% had a high-WBC. During induction, adverse events (AE) included grade 3/4 elevated bilirubin (21.1%), transaminases (14.7%), hyperglycemia (14.7%), hypofibrinogenemia (44.2%), thrombosis (10.5%), hypersensitivity (2.2%) and pancreatitis (2.1%). During consolidation, AE included grade 3/4 hepatic toxicity (18.9%), hypertriglyceridemia (14.8%), thrombosis (5.3%) and pancreatitis (2.1%). Neutropenic fever occurred in 55.8% during induction (grade 4: 31.5%), and in 32.9% during consolidation (grade 4/5: 5.3%). A dose adjustment due to AE was required in 22.1% during induction and in 23.2% during consolidation. The induction related-mortality (IRM) rate was 7.4% The CR rate was 87.8%. After-induction, MRD was <0.01% in 39.1%, 0.01-0.1% in 39.1% and > 0.1% in 24.6%. Post-consolidation MRD was only measured in 43 patients and was <0.01% in 37.2%. During follow-up, 26.7% relapsed: 62.5% bone marrow (BM) relapses, 25.0% central nervous system (CNS) relapses and 12.5% CNS + BM relapses. Eight patients (8.4%) received an allogeneic-stem cell transplant (HSCT) as consolidation. The 2-year OS was 72.1%. The post-induction MRD <0.1% was associated with a better OS (figure 1A) (HR: 0.17 (95%CI: 0.06-0.55), p=0.003) and a high-WBC with an inferior OS (figure 1B) (HR: 4.13 (95%CI: 1.68-10.14), p=0.002). The 2-year RFS was 65.2%. The post-induction MRD <0.1% was associate with a better RFS (figure 1C) (HR: 0.19 (95%CI: 0.07-0.50), p=0.001) and a high-WBC and overweight / obesity with an inferior RFS (HR: 4.08 (95%CI: 1.71-9.73), p=0.001 and 2.50 (95%CI: 1.06-5.86), p=0.036 respectively) (figure 1D). Conclusions: The adoption of modified CALGB10403 regimen in Central America based on local resources is feasible. It is associated with a significant improvement in the OS and decrease in IRM when compared with previous reports. Despite a very high-rate of hepatic and metabolic toxicities, these were manageable. As reported by other groups, MRD, high-WBC and overweight/obesity are associated with poor outcomes. Despite being encouraging results, a significant number of patients persist with positive MRD and the main cause of dead is disease progression. Access to cellular therapies, and BiTes is cost restricted in LMIC. Hence, we should generate strategies to intensify treatment in MRD positive patients and expand transplant access to overcome outcomes. Figure 1 Figure 1. Disclosures Rangel-Patiño: Bristol: Consultancy; Abbvie: Speakers Bureau. Ceniceros: Amgen: Speakers Bureau. Espinosa: Amgen: Speakers Bureau; Janssen: Consultancy; Pfizer: Consultancy. Amador: Abbvie: Consultancy, Speakers Bureau; Bristol: Consultancy. Cabrero Garcia: Takeda: Speakers Bureau; Abbvie: Speakers Bureau; Roche: Speakers Bureau; Janssen: Speakers Bureau; Astellas: Consultancy; BD: Speakers Bureau. Inclan-Alarcon: Janssen: Speakers Bureau; Boehringer: Speakers Bureau. Neme Yunes: Janssen: Consultancy, Speakers Bureau; Bristol: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Bristol: Consultancy, Speakers Bureau; Abbvie: Consultancy, Speakers Bureau; Abbvie: Speakers Bureau. Meillon-García: Amgen: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Roche: Speakers Bureau; Astellas: Consultancy. Apodaca: Sanofi: Consultancy; Asofarma: Consultancy, Speakers Bureau; Abbvie: Speakers Bureau. Demichelis: Bristol/Celgene: Consultancy, Speakers Bureau; Astellas: Consultancy; Gilead: Consultancy; ASH: Research Funding; Abbvie: Consultancy, Speakers Bureau; AMGEN: Consultancy, Speakers Bureau; Novartis: Consultancy, Research Funding, Speakers Bureau; Jazz: Consultancy.