Clonal Hematopoiesis and Inflammation in the VasculaturE (CHIVE): a prospective, longitudinal cohort and biorepository

Clonal hematopoiesis (CH) is an age-associated phenomenon leading to increased risk of both hematologic malignancy and non-malignant organ dysfunction. Increasingly available genetic testing has made incidental discovery of CH clinically common, yet evidence-based guidelines and effective management strategies to prevent adverse CH health outcomes are lacking. To address this gap, the prospective CHIVE registry and biorepository was created to identify and monitor individuals at risk, support multidisciplinary CH clinics, and to refine standards of practice for CH risk mitigation. Data from the first 181 patients enrolled in this registry recapitulate the molecular epidemiology of CH from biobank scale retrospective studies, with DNMT3A, TET2, ASXL1, and TP53 as the most commonly mutated genes. CH patients had higher rates of end organ dysfunction, in particular chronic kidney disease (p=0.001). Among patients with CH, variant allele frequency was independently associated with presence of cytopenias (p=0.008) and progression to hematologic malignancy (p=0.010), while other common high-risk CH clone features were not clear. Notably, accumulation of multiple distinct high-risk clone features was also associated with cytopenias (p=0.013) and hematologic malignancy progression (p=0.004), supporting a recently published CH risk score. Surprisingly, ~30% of patients enrolled in CHIVE from CH clinics were adjudicated as not having CHIP, highlighting the need for molecular standards and purpose-built assays in this field. Maintenance of this well-annotated cohort and continued expansion of CHIVE to multiple institutions is underway and will be critical to understand how to thoughtfully care for this patient population.

Waldenström Macroglobulinemia/Lymphoplasmacytic Lymphoma, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology

The treatment of Waldenström macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL) has evolved to include several new options. The NCCN Guidelines for WM/LPL provide a framework on which to base decisions regarding diagnosis, treatment, assessment of response to treatment, and follow-up of both newly diagnosed and previously treated WM/LPL.

Novel Heterozygous Missense Variants in Diacylglycerol Kinase Epsilon and Complement Factor I: Potential Pathogenic Association With Atypical Hemolytic Uremic Syndrome

Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy (TMA), which copresents with microangiopathic hemolytic anemia, thrombocytopenia, and kidney injury. While typical HUS is normally preceded by infections such as Shiga-toxin-producing Escherichia coli, atypical HUS (aHUS) has a genetic component that leads to dysregulation of the alternative complement pathway. We report a case of a 69-year-old female who developed aHUS after undergoing an elective knee surgery. Genetic testing revealed novel mutations affecting diacylglycerol kinase epsilon (DGKE) protein and complement factor I (CFI) that were not reported before as pathogenic. The patient was treated with eculizumab, leading to the complete resolution of TMA with no lasting organ damage.

Recommendations on prevention of infections during chimeric antigen receptor T-cell and bispecific antibody therapy in multiple myeloma

Chimeric antigen receptor T (CAR T) cell and bispecific antibody therapies have shown unprecedented efficacy in heavily pretreated patients with multiple myeloma (MM). However, their use is associated with a significant risk of severe infections, which can be attributed to various factors such as hypogammaglobulinemia, neutropenia, lymphopenia, T-cell exhaustion, cytokine-release syndrome and immune-effector cell-associated neurotoxicity syndrome. As these therapies have been recently approved by regulatory agencies, it is crucial to establish practical guidelines for infection monitoring and prevention until robust data from prospective clinical trials become available. To address this issue, a panel of experienced investigators from the Academic Consortium to Overcome Multiple Myeloma through Innovative Trials (COMMIT) developed consensus recommendations for mitigating infections associated with CAR T-cell and bispecific antibody therapies in MM patients.

Multiple Myeloma, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology

The treatment of relapsed/refractory multiple myeloma (MM) has evolved to include several new options. These include new combinations with second generation proteasome inhibitors (PI); second generation immunomodulators, monoclonal antibodies, CAR T cells, bispecific antibodies, selinexor, venetoclax, and many others. Most patients with MM undergo several cycles of remissions and relapse, and therefore need multiple lines of combination therapies. Selecting treatment options for relapsed/refractory MM requires consideration of resistance status to specific classes, and patient-specific factors such as age and other comorbidities should be considered. The NCCN Guidelines for MM provide a framework on which to base decisions regarding workup, treatment, and follow-up of newly diagnosed and previously treated MM. This manuscript outlines the recommendations from NCCN Guidelines for MM specific to relapsed/refractory disease.

Impacting T-cell fitness in multiple myeloma: potential roles for selinexor and XPO1 inhibitors

Competent T-cells with sufficient levels of fitness combat cancer formation and progression. In multiple myeloma (MM), T-cell exhaustion is caused by several factors including tumor burden, constant immune activation due to chronic disease, age, nutritional status, and certain MM treatments such as alkylating agents and proteasome inhibitors. Many currently used therapies, including bispecific T-cell engagers, anti-CD38 antibodies, proteasome inhibitors, and CART-cells, directly or indirectly depend on the anti-cancer activity of T-cells. Reduced T-cell fitness not only diminishes immune defenses, increasing patient susceptibility to opportunistic infections, but can impact effectiveness MM therapy effectiveness, bringing into focus sequencing strategies that could modulate T-cell fitness and potentially optimize overall benefit and clinical outcomes. Certain targeted agents used to treat MM, such as selective inhibitors of nuclear export (SINE) compounds, have the potential to mitigate T-cell exhaustion. Herein referred to as XPO1 inhibitors, SINE compounds inhibit the nuclear export protein exportin 1 (XPO1), which leads to nuclear retention and activation of tumor suppressor proteins and downregulation of oncoprotein expression. The XPO1 inhibitors selinexor and eltanexor reduced T-cell exhaustion in cell lines and animal models, suggesting their potential role in revitalizating these key effector cells. Additional clinical studies are needed to understand how T-cell fitness is impacted by diseases and therapeutic factors in MM, to potentially facilitate the optimal use of available treatments that depend on, and impact, T-cell function. This review summarizes the importance of T-cell fitness and the potential to optimize treatment using T-cell engaging therapies with a focus on XPO1 inhibitors.

Selinexor-Based Triplet Regimens in Patients With Multiple Myeloma Previously Treated With Anti-CD38 Monoclonal Antibodies

BACKGROUND

The increasing use of anti-CD38 monoclonal antibodies (αCD38 mAbs) for newly diagnosed or early relapsed multiple myeloma (MM), especially in non-transplant eligible patients, may lead to more patients developing αCD38 mAb-refractory disease earlier in the treatment course with fewer treatment options.

PATIENTS AND METHODS

We analyzed the efficacy and safety of selinexor-based triplets (selinexor+dexamethasone [Sd] plus pomalidomide [SPd, n = 23], bortezomib [SVd, n = 16] or carfilzomib (SKd, n = 23]) in a subset of STOMP (NCT02343042) and BOSTON (NCT03110562) study patients treated previously with αCD38 mAbs.

RESULTS

Sixty-two patients (median 4 prior therapies, range 1 to 11, 90.3% refractory to αCD38 mAb) were included. Overall response rates (ORR) in the SPd, SVd and SKd cohorts were 52.2%, 56.3%, and 65.2%, respectively. Overall response rate was 47.4% among patients who had MM refractory to the third drug reintroduced in the Sd-based triplet. Median progression-free survival in the SPd, SVd, and SKd cohorts was 8.7, 6.7, and 15.0 months, respectively, and median overall survival was 9.6, 16.9, and 33.0 months, respectively. Median time to discontinuation in the SPd, SVd, and SKd cohorts was 4.4, 5.9, and 10.6 months, respectively. The most common hematological adverse events were thrombocytopenia, anemia, and neutropenia. Nausea, fatigue, and diarrhea were primarily grade 1/2. Adverse events were generally manageable with standard supportive care and dose modifications.

CONCLUSION

Selinexor-based regimens may offer effective and well-tolerated therapy to patients with relapsed and/or refractory MM who had disease previously exposed or refractory to αCD38 mAb therapy and could help address the unmet clinical need in these high-risk patients.

Systemic Light Chain Amyloidosis, Version 2.2023, NCCN Clinical Practice Guidelines in Oncology

Primary systemic light chain amyloidosis (SLCA) is characterized by production of light chains that get converted to amyloid fibrils with an affinity for visceral organs and causing organ dysfunction. The therapy for SLCA is directed to recovering the function of the affected organs by targeting the abnormal plasma cell clone and slowing deposition of amyloid fibrils. The NCCN Guidelines for SLCA provide recommendations for workup, diagnosis, and treatment of primary as well as previously treated SLCA.

Development and implementation of "handshake rounds": An antibiotic stewardship intervention for hospitalized adult patients with hematologic malignancies

Objective

To design and implement "handshake rounds" as an antibiotic stewardship intervention to reduce inpatient intravenous (IV) antibiotic use in patients with hematologic malignancies.

Design

Quasi-experimental analysis of antibiotic use (AU) and secondary outcomes before and and after handshake rounds were implemented.

Setting

Quaternary-care, academic medical center.

Patients

Hospitalized adults with hematologic malignancies receiving IV antibiotics.

Methods

We performed a retrospective review of a preintervention cohort prior to the intervention. A multidisciplinary team developed criteria for de-escalation of antibiotics, logistics of handshake rounds, and outcome metrics. Eligible patients were discussed during scheduled handshake rounds between a hematology-oncology pharmacist and transplant-infectious diseases (TID) physician. Prospective data were collected over 30 days in the postintervention cohort. Due to small sample size, 2:1 matching was used to compare pre- to and postintervention AU. Total AU in days of therapy per 1,000 patient days (DOT/1,000 PD) was reported. Mean AU per patient was analyzed using Wilcoxon rank-sum test. A descriptive analysis of secondary outcomes of pre- and postintervention cohorts was performed.

Results

Total AU was substantially lower after the intervention, with 517 DOT/1,000 PD compared to 865 DOT/1,000 PD before the intervention. There was no statistically significant difference in the mean AU per patient between the 2 cohorts. There was a lower rate of 30-day mortality in the postintervention cohort and rates of ICU admissions were similar.

Conclusions

Conducting handshake rounds is a safe and effective way to implement an antibiotic stewardship intervention among high-risk patient population such as those with hematologic malignancies.

Selinexor-based regimens in patients with multiple myeloma after prior anti-B-cell maturation antigen treatment

There is a lack of consensus on therapy sequencing in previously treated multiple myeloma, particularly after anti-B-cell maturation antigen (BCMA) therapy. Earlier reports on selinexor (X) regimens demonstrated considerable efficacy in early treatment, and after anti-BCMA-targeted chimeric antigen receptor-T cell therapy. Here, we present data from 11 heavily pretreated patients who predominantly received BCMA-antibody-drug conjugate therapy. We observe that X-containing regimens are potent and achieve durable responses with numerically higher overall response and clinical benefit rates, as well as median progression free survival compared to patients' prior anti-BCMA therapies, despite being used later in the treatment course. In an area of evolving unmet need, these data reaffirm the efficacy of X-based regimens following broader anti-BCMA therapy.

Daratumumab plus lenalidomide, bortezomib and dexamethasone in newly diagnosed multiple myeloma: Analysis of vascular thrombotic events in the GRIFFIN study

Patients with multiple myeloma are at increased risk of vascular thromboembolic events (VTEs). This post hoc analysis evaluated VTEs in the randomised phase 2 GRIFFIN study (ClinicalTrials.gov Identifier: NCT02874742) that investigated lenalidomide/bortezomib/dexamethasone (RVd) ± daratumumab (D). Patients with newly diagnosed multiple myeloma who were eligible for autologous stem cell transplantation (ASCT) received D-RVd/RVd induction, high-dose therapy and ASCT, D-RVd/RVd consolidation and up to 2 years of lenalidomide maintenance therapy ± D. VTE prophylaxis was recommended (at least aspirin, ≥162 mg daily) in accordance with International Myeloma Working Group guidelines. In the safety population (D-RVd, n = 99; RVd, n = 102), VTEs occurred in 10.1% of D-RVd patients and 15.7% of RVd patients; grade 2-4 VTEs occurred in 9.1% and 14.7%, respectively. Median time to the first onset of VTE was longer for D-RVd versus RVd patients (305 days vs 119 days). Anti-thrombosis prophylaxis use was similar between arms (D-RVd, 84.8% vs RVd, 83.3%); among patients with VTEs, prophylaxis use at time of first VTE onset was 60.0% for D-RVd and 68.8% for RVd. In summary, the addition of daratumumab to RVd did not increase the incidence of VTEs, but the cumulative VTE incidence was relatively high in this cohort and anti-thrombotic prophylaxis use was suboptimal.

Optimizing Thromboembolism Prophylaxis for the Contemporary Age of Multiple Myeloma

Venous thromboembolism (VTE) is a major complication in all patients with cancer. Compared with the general population, patients with multiple myeloma (MM) have a 9-fold increase in VTE risk, likely because of their malignancy, its treatments, and other additional patient-related factors. In MM, thromboembolism events tend to occur within 6 months of treatment initiation, regardless of treatment regimen; however, the use of immunomodulatory agents such as thalidomide or lenalidomide, especially in combination with dexamethasone or multiagent chemotherapy, is known to create a significant risk for VTE. Currently, official recommendations for VTE prophylaxis in MM outlined in various national guidelines or multidisciplinary society panels are based on expert opinion, because data from randomized controlled trials are scarce. Large studies which have mainly focused on the efficacy of thromboprophylaxis in patients with cancer at higher risk for VTE either had a very low representation of patients with MM, or excluded them all together, limiting our ability to draw evidence-based conclusions on how to effectively protect MM population from VTE. In this brief perspective, we highlight some of the greatest challenges that have hampered the field concerning the availability of high-quality clinical trial data for the formulation of best VTE prophylaxis strategies in patients with newly diagnosed MM, as well as the rationale for the latest updates in the NCCN Guidelines on this topic.

NCCN Guidelines® Insights: Multiple Myeloma, Version 3.2022

The NCCN Guidelines for Multiple Myeloma provide recommendations for diagnosis, initial workup, treatment, follow-up, and supportive care for patients with various plasma cell neoplasms, including multiple myeloma. These NCCN Guidelines Insights highlight some of the important updates/changes specific to the treatment of patients with multiple myeloma in the 2022 version of the guidelines.

Bortezomib-Induced Perimyocarditis in a Multiple Myeloma Patient: A Case Report

Bortezomib (BTZ) is a proteasome inhibitor used in the treatment of multiple myeloma (MM) and other hematological malignancies. Although carfilzomib, a second-generation proteasome inhibitor, is most strongly associated with cardiotoxicity, BTZ has been associated with several cardiovascular complications including congestive heart failure, arrhythmias, and rarely myocarditis. Here, we report the first case of a BTZ-induced perimyocarditis. The patient was a 40-year-old woman with recently diagnosed MM who was admitted to the hospital with syncope at the start of her second cycle of induction therapy with BTZ, lenalidomide, and dexamethasone. She had a witnessed syncopal event in the emergency room with the telemetry showing sustained ventricular tachycardia. Laboratory workup showed elevated N-terminal pro B-type natriuretic peptide and normal troponin I. Transthoracic echocardiogram (TTE) showed a low ejection fraction of 40% with global hypokinesis of the left ventricle and trace pericardial effusion. Cardiac magnetic resonance imaging with gadolinium was consistent with acute myocarditis. The patient had recurrent pleuritic chest pain, and a repeat TTE showed worsening pericardial effusion consistent with pericarditis. Endomyocardial biopsy was done which showed nonspecific myocyte hypertrophy and foci of fibrosis, but was negative for giant cell myocarditis, hemochromatosis, and amyloidosis. Extensive infectious disease workup ruled out known infectious causes for perimyocarditis. Given the close timing between BTZ treatment (5 subcutaneous doses with a cumulative dose of 6.5 mg/m²), the absence of other iatrogenic or infectious causes, and probable or likely association with BTZ as assessed by the validated causality assessment scoring tools, it was concluded that the acute perimyocarditis was secondary to BTZ exposure. Here, we report the first case of BTZ-induced perimyocarditis and discuss the incidence and pathophysiology of BTZ-cardiovascular toxicity.

Cerebral Venous Sinus Thrombosis due to Thrombosis with Thrombocytopenia Syndrome Following Ad26.COV2.S: A First Real-World Case Report of a Male Subject

Thrombosis with Thrombocytopenia Syndrome (TTS) or Vaccine-induced Immune Thrombotic Thrombocytopenia (VITT) had been reported in patients receiving the Ad26.COV2.S vaccination (Johnson & Johnson [J&J]/Janssen) vaccine. They frequently presented with cerebral venous sinus thrombosis (CVST), but venous or arterial thrombosis at other locations can be present. The majority of those affected are younger adult females. Therefore, after a brief pause from April 13–23, 2021, the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA) recommended caution in using this vaccine in females under 50 years. Based on the reported 28 cases of TTS after this vaccination (data till April 21, 2021) by CDC, 22 were females (78%), and 6 were male. None of those males had CVST but had thrombosis at other locations. We report the first case of a young male with TTS and CVST following Ad26.COV2.S vaccine presented with severe headache and diagnosed with acute right transverse and sigmoid cerebral venous sinus thrombosis, multiple right-sided pulmonary emboli, and right hepatic vein thrombosis. He was treated with parenteral anticoagulation with argatroban and intravenous immune globulin with the improvement of his symptoms. A heparin-induced thrombocytopenia with thrombosis (HITT) like syndrome caused by the genesis of a platelet-activating autoantibody against platelet factor 4 (PF4) triggered by adenoviral vector-based COVID-19 vaccinations is understood to be the underlying pathophysiology. TTS with CVST should be considered when patients present with headaches, stroke-like neurological symptoms, thrombocytopenia, and symptom onset 6–15 days after Ad26.COV2.S vaccination.

Bortezomib-Induced Reversible Cardiomyopathy: Recovered with Guideline-Directed Medical Therapy

Bortezomib (BTZ) is a proteasome inhibitor (PI) used for the treatment of several hematologic malignancies, including multiple myeloma (MM), and various lymphomas including mantle cell lymphoma (MCL). It acts via disruption of the ubiquitin-proteasome pathway which plays a major role in regulating cell cycle and inhibiting synthesis of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-KB). The ubiquitin-proteasome pathway is also important in maintaining the integral signaling in cardiac myocytes. By inhibiting this system, BTZ induces cellular apoptosis in cancer cells, and possibly the cardiomyocytes. BTZ-induced cardiotoxicity in monotherapy and combination treatments is not well described in the literature.

We observed a series of three patients who developed cardiotoxicity after treatment with BTZ. All patients had echocardiograms every 3 months until recovery to assess ejection fraction (EF) and global longitudinal strain (GLS). Two of the patients had a cardiac MRI (CMR) conducted during follow-up to assess for late gadolinium enhancement (LGE). 

The median age of our patients was 55 years (range 37-74). Two of them had MM, while one patient had MCL. Table 1 demonstrates patient demographics, past medical histories, and the cumulative dose and duration of BTZ therapy. Of the three patients, only one had a heart failure exacerbation at diagnosis. The other two patients were diagnosed with asymptomatic left ventricular systolic dysfunction on routine pre-transplant echocardiograms. Most importantly, all three patients had improvement or normalization of cardiac function with discontinuation of BTZ and initiation of guideline-directed medical therapy (GDMT) for heart failure. The median duration to recovery was 5 months (range 3-13). One patient had underlying non-compaction cardiomyopathy, and although EF did not normalize, it recovered to his previous baseline. All 3 patients had improvement in GLS. Two patients underwent CMRI at the time of cardiomyopathy diagnosis and neither of them had any late gadolinium enhancement. Since there was no routine pre-treatment echocardiogram, using the GLS trend to detect subclinical cardiac dysfunction was not possible.

This case series demonstrates that BTZ-induced cardiomyopathy is potentially reversible with discontinuation of the drug and early initiation of GDMT. Further studies are needed to determine the ideal surveillance strategy for BTZ-induced cardiomyopathy. 

Once weekly selinexor, carfilzomib and dexamethasone in carfilzomib non-refractory multiple myeloma patients

Background

Proteasome inhibitors (PIs), including carfilzomib, potentiate the activity of selinexor, a novel, first-in-class, oral selective inhibitor of nuclear export (SINE) compound, in preclinical models of multiple myeloma (MM).

Methods

The safety, efficacy, maximum-tolerated dose (MTD) and recommended phase 2 dose (RP2D) of selinexor (80 or 100 mg) + carfilzomib (56 or 70 mg/m²) + dexamethasone (40 mg) (XKd) once weekly (QW) was evaluated in patients with relapsed refractory MM (RRMM) not refractory to carfilzomib.

Results

Thirty-two patients, median prior therapies 4 (range, 1–8), were enrolled. MM was triple-class refractory in 38% of patients and 53% of patients had high-risk cytogenetics del(17p), t(4;14), t(14;16) and/or gain 1q. Common treatment-related adverse events (all/Grade 3) were thrombocytopenia 72%/47% (G3 and G4), nausea 72%/6%, anaemia 53%/19% and fatigue 53%/9%, all expected and manageable with supportive care and dose modifications. MTD and RP2D were identified as selinexor 80 mg, carfilzomib 56 mg/m², and dexamethasone 40 mg, all QW. The overall response rate was 78% including 14 (44%) ≥ very good partial responses. Median progression-free survival was 15 months.

Conclusions

Weekly XKd is highly effective and well-tolerated. These data support further investigation of XKd in patients with MM.

The evaluation and management of monoclonal gammopathy of renal significance and monoclonal gammopathy of neurological significance

Despite the benign nature of monoclonal gammopathy of undetermined significance (MGUS), mounting data are associating MGUS with the development of organ dysfunction, specifically monoclonal gammopathy of renal significance (MGRS) and monoclonal gammopathy of neurological significance (MGNS), which could be associated with substantial morbidity. Emerging evidence suggests that patients with MGRS and MGNS could benefit from treatments used for myeloma, Waldenström macroglobulinemia, or chronic lymphocytic leukemia, depending on the underlying pathology. However, the treatment of MGRS and MGNS is not standardized, and potentially effective therapies might not be reimbursed because these conditions do not formally meet the criteria for malignant processes. The present review aims at establishing standards for the evaluation and management of MGRS and MGNS, which can facilitate the diagnosis of and provide therapeutic options for treating practitioners and patients affected by these conditions. The careful design and execution of clinical trials for patients with MGRS and MGNS are positively encouraged.

Selinexor containing regimens in patients with multiple myeloma (MM) previously treated with anti-CD38 monoclonal antibodies (αCD38 mAbs)

e20020

Background: Exportin 1 (XPO1) mediates the nuclear export and functional inactivation of tumor suppressor proteins, is required for MM growth, is associated with poor prognosis in MM and mediates resistance to standard MM therapies. Selinexor (SEL) is a first-in-class, oral selective inhibitor of nuclear export (SINE) compound approved in combination with dexamethasone (dex) ± bortezomib for patients (pts) with previously treated MM. Once MM becomes refractory to αCD38 mAb, pts have limited effective treatment options and poor prognosis. Overall response rate (ORR) to the first regimen after refractoriness to an αCD38 mAb is 31%, median progression-free survival (mPFS) is 3.4 months (m), and median overall survival (mOS) is 8.6 m. The doublet SEL-dex (Xd) has shown ORR ̃26% in triple-class (IMID, PI, αCD38 mAb) refractory MM; SEL-based triplets could be more effective in this population. Methods: STOMP (Selinexor and Backbone Treatments of Multiple Myeloma Patients) is a multi-arm, open-label, Phase 1b/2 study evaluating SEL in various triplet combinations. Here, we retrospectively analyzed the efficacy and safety of SEL-containing triplets in pts previously treated with αCD38 mAbs. Pts received SEL-dex (Xd) plus pomalidomide (XPd, n = 19), bortezomib (XVd, n = 4), lenalidomide (XRd, n = 4), daratumumab (XDd, n = 2) or carfilzomib (XKd, n = 18). ORR, mOS, mPFS and adverse events (AEs) were analyzed. Results: Among the 47 pts, median age 64 yrs, female 53%, median time from diagnosis 5.1 yrs, median number of prior regimens 5 (range, 2–11). Prior daratumumab (96%), isatuximab (4%); 96% had MM refractory to aCD38 mAb, 81% had triple-class refractory MM, 74% and 47% were quad- and penta-exposed, 43% and 15% had quad- and penta-refractory MM. αCD38 mAb was included in the immediate prior regimen of 57% of pts and median duration from end of most recent aCD38 mAb therapy to first dose of study treatment was 6.9 weeks (range, 2.6-114.9). ORR was 51% among the 45 evaluable pts, 59% in the XPd arm (n = 17; 2 pts were not efficacy evaluable) and 67% in the XKd arm. ORR was 47% (9/19) among pts with quad-refractory MM and evaluable efficacy. Among all evaluable pts mPFS was 8.8 m (95% CI: 4.9, NE) and mOS was 20.4 m (95% CI: 9.6, NE). Among the 25 pts with αCD38 mAb in their immediate prior regimen, efficacy was similar to that regimen: ORR 52% vs. 45%, mPFS 8.8 vs. 9.3 m. The most common treatment emergent AEs were nausea (72%), anemia (64%), thrombocytopenia (60%), fatigue (57%), which were managed with standard supportive care and dose modifications. Conclusions: SEL-containing triplets in pts with MM previously treated with αCD38 mAbs, most of whom had triple-class refractory MM, exhibit tolerability and comparable effectiveness to their most recent αCD38 mAb-containing regimens. Compared to historical control, mOS was much higher among these patients. Further investigation is warranted. Clinical trial information: NCT02343042.

Oral selinexor, pomalidomide, and dexamethasone (XPd) at recommended phase 2 dose in relapsed refractory multiple myeloma (MM)

8018

Background: Exportin 1 (XPO1) mediates the nuclear export and functional inactivation of tumor suppressor proteins (TSPs), is associated with poor prognosis in MM, and contributes to proteasome inhibitor (PI) and immunomodulatory drug (IMiD) resistance. Selinexor (SEL) is a novel, oral, first-in-class selective inhibitor of nuclear export (SINE) compound that blocks XPO1, forcing the nuclear retention and activation of TSPs. SEL is approved with low-dose dexamethasone (dex) ± bortezomib (BOR) for patients (pts) with previously treated MM. In the Phase 3 BOSTON study, once weekly (QW) SEL, QW BOR, and dex (XVd) significantly increased progression-free survival (PFS) and overall response rate (ORR) with marked reduction of peripheral neuropathy as compared to standard twice weekly BOR/dex (Vd), despite XVd utilizing 40% less BOR and 25% less dex than Vd. Pomalidomide (POM) plus dex (Pd) has an ORR of 31% and median PFS (mPFS) of 4 months in MM pts refractory to BOR and lenalidomide (LEN). We hypothesized that the addition of once weekly SEL to Pd (XPd) would be an active, all-oral combination with an acceptable safety profile in pts with LEN refractory and BOR treated MM. Methods: In the SPd arm of the multi-arm Phase 1b/2 STOMP study, SEL was evaluated at 60, 80, or 100 mg QW or 60 or 80 mg twice weekly in combination with Pd. Study objectives were to determine the maximum tolerated dose and recommended Phase 2 dose (RP2D), and assess the safety and activity of the SPd regimen including in pts receiving the RP2D. Results: As of 4 Jan 2021, 65 pts (33 male) were enrolled with median age of 64 years (range 37-85 years) and median of 3 (range 1-10) prior lines of therapy. Previously treated/refractory rates were LEN 100%/85%, BOR 92%/49%, carfilzomib 43%/37%, POM 31%/29%, and daratumumab (dara) 26%/26%. RP2D was SEL 60 mg QW, POM 4 mg (days 1-21), dex 40 mg QW. Common hematologic, treatment-related adverse events (TRAEs) included (all grades, grades ≥3) neutropenia (63%, 55%), anemia (58%, 32%), and thrombocytopenia (54%, 31%). Non-hematologic TRAEs included nausea (62%, 2%), fatigue (55%, 11%), and decreased appetite (45%, 2%). Among POM naïve or nonrefractory MM pts (N = 44), ORR was 57% (1 sCR, 1 CR, 8 VGPR, 15 PR); mPFS was 12.2 months. In pts treated with RP2D (N = 20), ORR was 65% (1 sCR, 5 VGPR, 7 PR); mPFS was not reached with a median follow-up time of 3.9 months. In POM-refractory pts and those with prior dara, ORR was 44% (7/16) and 60% (9/15), respectively. Conclusions: SEL, once weekly, can be safely combined with Pd in pts with heavily pretreated MM. No new safety signals were identified. The all-oral combination of XPd is highly active with an ORR of 65% at RP2D (compared to expected ORR ≤30% for Pd) and produces durable responses with a mPFS of 12.2 months overall. These data support a planned Phase 3 study with an all-oral combination of XPd vs Pd in pts who have been previously treated with LEN, a PI, and an anti-CD38 mAb. Clinical trial information: NCT02343042.

Once weekly selinexor, carfilzomib, and dexamethasone (XKd) in carfilzomib nonrefractory multiple myeloma (MM) patients

8038

Background: Exportin 1 (XPO1) mediates the nuclear export and functional inactivation of tumor suppressor proteins (TSPs), is associated with poor prognosis in MM, and contributes to proteasome inhibitor (PI) and immunomodulatory drug (IMiD) resistance. Selinexor (SEL) is a novel, oral, first-in-class selective inhibitor of nuclear export (SINE) compound that blocks XPO1, forcing the nuclear retention and activation of TSPs. SEL in combination with low dose dexamethasone (dex) ± bortezomib (BOR) is FDA approved for previously treated MM. The synergy of SEL with the PI BOR has been confirmed in the phase 3 BOSTON study in MM patients (pts) with 1-3 prior therapies; once weekly (QW) SEL, QW BOR, and dex (XVd) significantly increased progression-free survival (PFS), time to next therapy, and overall response rate (ORR) as compared to standard twice weekly BOR/dex (Vd), despite XVd using 40% less BOR and 25% less dex than standard Vd. We hypothesized that the addition of QW SEL to the PI carfilzomib (CAR)-dex (XKd) would be an active and tolerable regimen in pts with heavily pretreated MM. Methods: In the XKd arm of the multi-arm Phase 1b/2 STOMP study, SEL at 80 or 100 mg QW was evaluated in combination with CAR at 56 or 70 mg/m2 QW plus dex at 40 mg QW in pts with heavily pretreated MM not refractory to CAR. Study objectives were to determine the maximum tolerated dose and recommended phase 2 dose (RP2D) and assess the safety and activity of the XKd regimen. Results: As of 4Jan2021, 27 pts were enrolled: 18 (67%) were male, median age 71 years (range 50-76), and median of 4 (range 1-8) prior lines of therapy. All 27 pts were previously treated with BOR, 26 (96%) lenalidomide (LEN), 19 (70%) pomalidomide (POM), 18 (67%) daratumumab (dara). The majority (67%) of pts were triple-class pretreated (PI, IMiD, and anti-CD38 mAb), and 44% had triple-class refractory MM. Nine pts (33%) had MM quad-refractory to BOR, LEN, POM, and dara. Common hematologic treatment-related adverse events (TRAEs) (total, grade ≥3) included thrombocytopenia (74%, 56%), anemia (59%, 19%), and neutropenia (30%, 7%). Non-hematologic TRAEs included nausea (67%, 4%), fatigue (52%, 7%), and anorexia (52%, 4%). RP2D was identified as SEL 80 mg QW, CAR 56 mg/m2 QW, and dex 40 mg QW. As of 3Feb2021, ORR was 78% (21/27) with 5 pts reaching CR (19%), 8 VGPR (30%), and 8 PR (30%). Median PFS was 23.7 months. Among 18 pts pretreated with dara, ORR was 67% and median PFS 23.7 months. In 9 pts whose MM was refractory to BOR, LEN, POM, and dara, ORR was 67% with 4 VGPR (44%). Conclusions: In pts with heavily pretreated MM, weekly XKd is highly active with an ORR of 78% and deep responses (≥VGPR 48%) with an overall PFS of 23 months. All AEs including grade 3/4 thrombocytopenia can be managed with appropriate supportive care and dose modifications. These data support further investigation of XKd in pts with previously treated MM including those previously treated with dara.

Multiple Myeloma, Version 3.2021, NCCN Clinical Practice Guidelines in Oncology

Multiple myeloma is a malignant neoplasm of plasma cells that accumulate in bone marrow, leading to bone destruction and marrow failure. This manuscript discusses the management of patients with solitary plasmacytoma, smoldering multiple myeloma, and newly diagnosed multiple myeloma.

Selinexor, daratumumab, and dexamethasone in patients with relapsed or refractory multiple myeloma

We assessed the safety, efficacy, maximum tolerated dose (MTD), and the recommended phase 2 dose (RP2D) of selinexor, a first in class oral selective inhibitor of nuclear export (100 mg once weekly [QW] or 60 mg twice weekly), in combination with daratumumab (16 mg/kg per label) and dexamethasone (40 mg QW) (SDd) in patients with relapsed refractory multiple myeloma (RRMM). Thirty‐four patients (median prior therapies, 3 [range, 2‐10]) were enrolled; MM was refractory to proteasome inhibitor (PI) in 85%, immunomodulatory agent (IMiD) in 76%, both in 74%, and daratumumab in 6% of patients. Two dose‐limiting toxicities (DLTs) were reported in the selinexor 60 mg twice‐weekly cohort with no DLTs in the 100 mg QW cohort, making 100 mg QW the MTD and RP2D. Common treatment‐related adverse events included thrombocytopenia (70.6%), nausea (70.6%), fatigue (61.8%), anemia (61.8%), and neutropenia (50.0%). Overall response rate was 73% and median progression‐free survival 12.5 months in daratumumab‐naïve patients. SDd was well tolerated and its promising efficacy suggests that further study of this PI‐ and IMiD‐free regimen in RRMM patients who had at least one prior line of therapy including a PI and an IMiD but whose disease is naïve to daratumumab is warranted.

Intravenous Immunoglobulin G Suppresses Heat Shock Protein (HSP)-70 Expression and Enhances the Activity of HSP90 and Proteasome Inhibitors

Intravenous immunoglobulin G (IVIgG) is approved for primary immunodeficiency syndromes but may induce anti-cancer effects, and while this has been attributed to its anti-inflammatory properties, IgG against specific tumor targets may play a role. We evaluated IVIgG alone, and with a Heat shock protein (HSP)-90 or proteasome inhibitor, using multiple myeloma and mantle cell lymphoma (MCL) cells in vitro, and with the proteasome inhibitor bortezomib in vivo. IVIgG inhibited the growth of all cell lines tested, induced G₁ cell cycle arrest, and suppressed pro-tumor cytokines including Interleukin (IL)-6, IL-8, and IL-10. Genomic and proteomic studies showed that IVIgG reduced tumor cell HSP70-1 levels by suppressing the ability of extracellular HSP70-1 to stimulate endogenous HSP70-1 promoter activity, and reduced extracellular vesicle uptake. Preparations of IVIgG were found to contain high titers of anti-HSP70-1 IgG, and recombinant HSP70-1 reduced the efficacy of IVIgG to suppress HSP70-1 levels. Combining IVIgG with the HSP90 inhibitor AUY922 produced superior cell growth inhibition and correlated with HSP70-1 suppression. Also, IVIgG with bortezomib or carfilzomib was superior to each single agent, and enhanced bortezomib's activity in bortezomib-resistant myeloma cells. Moreover, IVIgG reduced transfer of extracellular vesicles (EVs) to cells, and blocked transfer of bortezomib resistance through EVs. Finally, IVIgG with bortezomib were superior to the single agents in an in vivo myeloma model. These studies support the possibility that anti-HSP70-1 IgG contained in IVIgG can inhibit myeloma and MCL growth by interfering with a novel mechanism involving uptake of exogenous HSP70-1 which then induces its own promoter.

NCCN Guidelines Insights: Multiple Myeloma, Version 1.2020

The NCCN Guidelines for Multiple Myeloma provide recommendations for diagnosis, workup, treatment, follow-up, and supportive care for patients with monoclonal gammopathy of renal significance, solitary plasmacytoma, smoldering myeloma, and multiple myeloma. These NCCN Guidelines Insights highlight some of the important updates and changes in the 1.2020 version of the NCCN Guidelines for Multiple Myeloma.

Once weekly selinexor, carfilzomib, and dexamethasone (SKd) in patients with relapsed/refractory multiple myeloma (MM)

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Background: Selinexor is a novel, first-in-class selective inhibitor of nuclear export (SINE), which blocks exportin 1 (XPO1), forcing the nuclear retention and activation of tumor suppressor proteins. Selinexor in combination with low dose dexamethasone (Sel-dex) was approved by the FDA, based on data from the STORM study wherein Sel-dex induced an overall response rate (ORR) of 26.2% in patients (pts) with refractory MM. We hypothesize that once weekly (QW) SKd may be an active well tolerated regimen and evaluated this combination in a dose escalation/expansion study. Methods: STOMP is a phase 1b/2 study evaluating various doses and enrolled pts with carfilzomib naive relapsed MM. Oral selinexor was dosed QW at 80 or 100 mg. Carfilzomib was dosed QW (on days 1, 8 and 15 of 28-day cycle) at 56 mg/m2 or 70 mg/m2. Dexamethasone was dosed at 40 mg QW. The primary objectives of the study are to assess the maximum tolerated dose (MTD), recommended phase 2 dose (RP2D), as well as explore the efficacy and safety of SKd. Results: As of January 2020, 18 pts were enrolled. Median age was 71 years (range: 50-76). Median number of prior regimens was 4 (range: 1-8). All pts (n = 18) were previously treated with bortezomib and lenalidomide, and 50% and 56% pts were refractory to bortezomib and lenalidomide respectively. Nine (50%) pts received prior pomalidomide treatment and 8 (44%) pts were refractory. Eleven (61%) pts received prior daratumumab treatment and 9 (50%) were refractory. The MTD was selinexor 80 mg QW, carfilzomib 56 mg/m2 QW and dexamethasone 40 mg QW. The ORR and CBR were 72% and 79% respectively with 4 complete responses, 7 very good partial responses, 2 partial responses, and 1 minimal response. Stable disease was observed in 3 pts. With a median follow-up period of 4.7 (1.8-16.3) months, median progression-free survival has not been reached. Common treatment-related adverse events (total, Grade ≥3) were thrombocytopenia (83.3%, 66.7%), nausea (66.7%, 0%), anemia (55.6%, 11.1%), fatigue (50%, 11.1%), anorexia (44%, 5.6%), weight loss (44%, 0%), and neutropenia (33.3%, 11.1%). Conclusions: Once weekly SKd demonstrated an encouraging ORR of 72% in pts with a median of 4 lines of prior therapy. The majority of responses are deep and predominantly CR and VGPR. The combination is well tolerated with no new safety signal, no Grade ≥3 nausea, vomiting, diarrhea, weight loss or anorexia. The side effects are a function of the dose and schedule and can be managed with dose modification and supportive care. Enrolment is ongoing and supports a phase 3 study of SKd. Clinical trial information: NCT02343042 .

Selinexor, daratumumab, and dexamethasone in patients with relapsed/refractory multiple myeloma (MM)

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Background: Selinexor is a first-in-class oral Selective Inhibitor of Nuclear Export (SINE) compound that binds and inactivates exportin 1 (XPO1). Selinexor in combination with low dose dexamethasone (Sel-dex) was approved by the FDA, based on data from the STORM study, wherein Sel-dex induced an overall response rate (ORR) of 26.2% in patients (pts) with relapsed/refractory MM (RRMM). Single agent daratumumab has demonstrated an ORR of 29% in MM reftactory to proteasome inhibitors (PIs)/immunomodulatory drug (IMiDs). We evaluated the safety, tolerability and preliminary efficacy of the combination of Sel-dex and daratumumab (SDd) in pts with MM refractory to PIs/IMiDs. Methods: This is a multicenter, open-label, phase 1b/2 dose escalation and expansion study. Pts were eligible if they had received ≥ 3 prior lines of therapy, including a PI and an IMiD, or whose MM was refractory to a PI and an IMiD. In the expansion phase, pts were required to be anti-CD38 monoclonal antibody-naïve. One dose level was tested at each schedule: selinexor once-weekly (QW at 100 mg) or twice-weekly (BIW at 60 mg) with dexamethasone 40 mg. Daratumumab 16 mg/kg IV was administered per label. Primary objective was to determine the maximum tolerated dose and recommended phase 2 dose (RP2D), and assess safety, tolerability and efficacy of SDd in pts with RRMM. Results: A total of 34 pts were enrolled; 3 in the 60 mg BIW and 31 in the 100 mg QW cohorts. Median age was 69 and median number of prior treatment regimens was 3 (range, 1–10). Out of 34 pts, 62% and 65% were refractory to bortezomib and lenalidomide respectively. Common treatment related adverse events (all grades, grades 3/4) included: thrombocytopenia (71%, 47%), fatigue (62%, 18%), nausea (71%, 9%), anemia (62%, 32%) and neutropenia (50%, 26%). Two dose limiting toxicities (DLTs) were reported in the 60 mg BIW cohort: Grade 3 thrombocytopenia and Grade 2 fatigue requiring dose reduction in selinexor to 100 mg QW. In the 100 mg QW escalation cohort (n = 6), no DLTs occured. 32 patients were evaluable for efficacy. The ORR was 73% (11 VGPR, 11 PR) for 30 daratumumab-naïve pts. Median progression-free survival was 12.5 months in both groups. Conclusions: Based on tolerability and efficacy, the RP2D of SDd is selinexor 100 mg, daratumumab 16 mg/kg and dexamethasone 40 mg, administered QW. In pts with PI and IMiD refractory MM, weekly SDd demonstrated promising activity with an ORR of 73% in daratumumab-naïve pts and a median PFS of 12.5 months. This supports further development of a novel non-PI, non-IMiD backbone in earlier lines of therapy. Clinical trial information: NCT02343042 .

Present and Future of Immunotherapy in the Management of Multiple Myeloma

Multiple myeloma (MM) is the second most common hematologic malignancy with an increasing incidence and prevalence. The wide array of effective antimyeloma agents have transformed MM into a chronic condition for some patients, requiring long-term management planning. Immunomodulatory drugs and proteasome inhibitors have played a pivotal role in defining the most effective regimens for both transplantation-eligible and transplantation-ineligible subgroups. Nevertheless, recent approvals of immunotherapies in MM such as daratumumab have added another important component to combination treatments for both relapsed or refractory and newly diagnosed disease. Evolving novel therapies such as chimeric antigen receptor T cells are poised to raise the bar even further, holding a promise of effective treatment option for patients who would otherwise have limited treatment alternatives. As we continue to therapeutically exploit the essential roles of cell-mediated immune surveillance, antigen presentation, and modulation of inhibitory surface signaling, we are rapidly establishing the cornerstone role of immunotherapies in the management of all phases of MM. In this review, we will cover the spectrum of available immunotherapies approved for clinical use in MM, as well as briefly describe those in early- and late-phase development, with the focus of raising the awareness of the expanding immuno-oncology armamentarium in MM.

Pharmacodynamics and pharmacokinetics of proteasome inhibitors for the treatment of multiple myeloma

Introduction: Multiple myeloma (MM) is the second most commonly diagnosed hematologic malignancy and has an increasing incidence and prevalence globally, and proteasome inhibitors (PIs) form the backbone of some of our most effective regimens for all phases of this disease in fit and frail patients. Areas covered: Strong understanding of the proteasome complex is increasingly important as the rapid development of new PIs and innovative myeloma therapies complicate the use of old and new combination regimens. We focus herein on the pharmacodynamics and pharmacokinetics of the approved PIs and others in development, including their safety and efficacy in corresponding clinical studies. Expert opinion: Advancements such as the first oral PI, ixazomib, with a more convenient route of administration and improved toxicity profile led to an improved quality of life, patient compliance, and all-oral combination regimens which are efficacious for long-term management of standard and high-risk MM. Novel pan-PIs, such as marizomib, hold the promise of superior clinical activity due to irreversible targeting of all multicatalytic proteinase complex subunits. Development of clinically validated biomarkers of PI sensitivity/resistance is required to inform utilization of the most optimal and effective, rationally targeted PI treatments for all MM patients.

Serendipitous Discovery of Factor VII Deficiency and the Ensuing Dilemma

Congenital factor VII deficiency is a challenging disorder to manage, as it is associated with varied genotypes that do not clinically correlate with a bleeding phenotype. Individuals with severe factor VII deficiency (FVII: c <1%) might be asymptomatic, while patients with moderate deficiency (FVII: c level >5%) may experience severe hemorrhages. In modern medicine, due to extensive routine pre-operative laboratory testing, clinically asymptomatic patients without any bleeding history might be incidentally discovered, raising clinical dilemmas. Careful consideration of bleeding versus thrombosis risk has to be made in such cases, especially in the elderly. Clinical history of no prior bleeding complications may be a reassuring factor. Minimal required replacement dosing of recombinant activated factor VII can be given peri-operatively in such situations, with close monitoring.

Phase II study of the c-MET inhibitor tivantinib (ARQ 197) in patients with relapsed or relapsed/refractory multiple myeloma

The hepatocyte growth factor/c-MET pathway has been implicated in the pathobiology of multiple myeloma, and c-MET inhibitors induce myeloma cell apoptosis, suggesting that they could be useful clinically. We conducted a phase II study with the c-MET inhibitor tivantinib in patients with relapsed, or relapsed and refractory myeloma whose disease had progressed after one to four prior therapies. Tivantinib, 360 mg orally per dose, was administered twice daily continuously over a 4-week treatment cycle without a cap on the number of allowed cycles, barring undue toxicities or disease progression. Primary objectives were to determine the overall response rate and the toxicities of tivantinib in this patient population. Sixteen patients were enrolled in a two-stage design. Notable grade 3 and 4 hematological adverse events were limited to neutropenia in five and four patients, respectively. Nonhematological adverse events of grade 3 or higher included hypertension (in four patients); syncope, infection, and pain (two each); and fatigue, cough, and pulmonary embolism (one each). Four of 11 evaluable patients (36%) had stable disease as their best response, while the remainder showed disease progression. Overall, tivantinib as a single agent did not show promise for unselected relapsed/refractory myeloma patients. However, the ability to achieve stable disease does suggest that combination regimens incorporating targeted inhibitors in patients with c-MET pathway activation could be of interest.

Telomere Length Recovery: A Strong Predictor of Overall Survival in Acute Promyelocytic Leukemia

Telomeres are the capping ends of chromosomes that protect the loss of genetic material and prevent chromosomal instability. In human tissue-specific stem/progenitor cells, telomere length (TL) is maintained by the telomerase complex, which consists of a reverse transcriptase catalytic subunit (TERT) and an RNA template (TERC). Very short telomeres and loss-of-function mutations in the TERT and TERC genes have been reported in acute myeloid leukemia, but the role of telomeres in acute promyelocytic leukemia (APL) has not been well established. We report the results for a large cohort of 187 PML/RARα-positive APL patients. No germline mutations in the TERT or TERC genes were identified. Codon 279 and 1062 TERT polymorphisms were present at a frequency similar to that in the general population. TL measured in blood or marrow mononuclear cells at diagnosis was significantly shorter in the APL patients than in healthy volunteers, and shorter telomeres at diagnosis were significantly associated with high-risk disease. For patients who achieved complete remission, the median increase in TL from diagnosis to remission (delta TL) was 2.0 kilobase (kb), and we found delta TL to be the most powerful predictor of overall survival when compared with well-established risk factors for poor outcomes in APL.

Mutational cooperativity linked to combinatorial epigenetic gain of function in acute myeloid leukemia

Specific combinations of acute myeloid leukemia (AML) disease alleles, including FLT3 and TET2 mutations, confer distinct biologic features and adverse outcome. We generated mice with mutations in Tet2 and Flt3, which resulted in fully penetrant, lethal AML. Multipotent Tet2(-/-);Flt3(ITD) progenitors (LSK CD48(+)CD150(-)) propagate disease in secondary recipients and were refractory to standard AML chemotherapy and FLT3-targeted therapy. Flt3(ITD) mutations and Tet2 loss cooperatively remodeled DNA methylation and gene expression to an extent not seen with either mutant allele alone, including at the Gata2 locus. Re-expression of Gata2 induced differentiation in AML stem cells and attenuated leukemogenesis. TET2 and FLT3 mutations cooperatively induce AML, with a defined leukemia stem cell population characterized by site-specific changes in DNA methylation and gene expression.

Translocation t(11;17) in de novo myelodysplastic syndrome not associated with acute myeloid or acute promyelocytic leukemia

Translocation t(11;17) is a well-recognized variant of acute promyelocytic leukemia (APL) and has also been identified in patients with mixed-lineage leukemia (MLL) non-APL acute myeloid leukemia. Here, we describe two patients bearing translocation t(11;17) presenting with a clinical diagnosis of de novo myelodysplastic syndrome (MDS): the first with sole karyotypic abnormality 46,XY,t(11;17)(p11.2; p13) and the second where it represented one of the two karyotypic abnormalities 46,XX,del(5)(q13q33)46,XX,del(5)(q13q33),t(11;17)(q24;q23). Molecular characterization of both cases failed to identify fusion transcripts involving MLL or PLZF-RARA and no collaborating somatic mutations commonly found among MDS patients were seen in either case, suggesting the presence of an as yet unidentified oncogenic fusion protein.

Curing all patients with acute promyelocytic leukemia: are we there yet?

The introduction of all-trans retinoic acid to anthracycline-based chemotherapy has revolutionized the prognosis of patients with acute promyelocytic leukemia (APL). The introduction of arsenic trioxide enabled the therapeutic approach of rationally targeted frontline protocols with minimal or no traditional cytotoxic chemotherapy and without compromise of previously established outstanding outcomes with anthracycline-based regimens. Although most of the current investigative efforts in APL are focused on developing potentially curative therapy without the exposure to toxicities and risks of DNA-disrupting agents, the cure rate can further be increased by implementing meticulous supportive care strategies that counter early coagulopathy-related deaths.

Ethics of medical care for body packers (drug smugglers): untangling a web of fears and conflicts of interest

Body packing by drug smugglers--the transport of illicit drugs in packets swallowed or inserted into body cavities--is a global phenomenon and is becoming more prevalent. The medical care of these patients raises difficult medical and ethical problems. While the medical aspects of treating body packers have been systematically analysed, the ethical issues have received little attention in the literature. The patient may be under police custody or being sought by their criminal patron which may result in imposed interrogations and risky medical procedures. Obtaining informed valid consent for procedures from the patient-detainee may thus be compromised. In addition, physicians may be intimidated by the patient's criminal contacts. This article analyses the conflicts of interest that doctors may face when treating body packers, and proposes some principles to promote institutional guidelines for the treatment of these patients.

Slitrk5 deficiency impairs corticostriatal circuitry and leads to obsessive-compulsive-like behaviors in mice

Obsessive-compulsive disorder (OCD) is a common psychiatric disorder defined by the presence of obsessive thoughts and repetitive compulsive actions, and it often encompasses anxiety and depressive symptoms. Recently, the corticostriatal circuitry has been implicated in the pathogenesis of OCD. However, the etiology, pathophysiology and molecular basis of OCD remain unknown. Several studies indicate that the pathogenesis of OCD has a genetic component. Here we demonstrate that loss of a neuron-specific transmembrane protein, SLIT and NTRK-like protein-5 (Slitrk5), leads to OCD-like behaviors in mice, which manifests as excessive self-grooming and increased anxiety-like behaviors, and is alleviated by the selective serotonin reuptake inhibitor fluoxetine. Slitrk5(-/-) mice show selective overactivation of the orbitofrontal cortex, abnormalities in striatal anatomy and cell morphology and alterations in glutamate receptor composition, which contribute to deficient corticostriatal neurotransmission. Thus, our studies identify Slitrk5 as an essential molecule at corticostriatal synapses and provide a new mouse model of OCD-like behaviors.

Angiomodulin is a specific marker of vasculature and regulates vascular endothelial growth factor-A-dependent neoangiogenesis

Blood vessel formation is controlled by the balance between pro- and antiangiogenic pathways. Although much is known about the factors that drive sprouting of neovessels, the factors that stabilize and pattern neovessels are undefined. The expression of angiomodulin (AGM), a vascular endothelial growth factor (VEGF)-A binding protein, was increased in the vasculature of several human tumors as compared to normal tissue, raising the hypothesis that AGM may modulate VEGF-A-dependent vascular patterning. To elucidate the expression pattern of AGM, we developed an AGM knockin reporter mouse (AGM(lacZ/+)), with which we demonstrate that AGM is predominantly expressed in the vasculature of developing embryos and adult organs. During physiological and pathological angiogenesis, AGM is upregulated in the angiogenic vasculature. Using the zebrafish model, we found that AGM is restricted to developing vasculature by 17 to 22 hours postfertilization. Blockade of AGM activity with morpholino oligomers results in prominent angiogenesis defects in vascular sprouting and remodeling. Concurrent knockdown of both AGM and VEGF-A results in synergistic angiogenesis defects. When VEGF-A is overexpressed, the compensatory induction of the VEGF-A receptor, VEGFR2/flk-1, is blocked by the simultaneous injection of AGM morpholino oligomers. These results demonstrate that the vascular-specific marker AGM modulates vascular remodeling in part by temporizing the proangiogenic effects of VEGF-A.

“Body Packing” and its Implications in Qatar

The internal concealment of highly profitable illicit drugs such as cocaine and heroin, by means of body packing is an important means of international drug trafficking. This phenomenon is apparently uncommon in Qatar, with only one reported case thus far. Here, we present a case of body packer who was transiting Doha and was found to be carrying 90 internalized packets of heroin. Regardless of whether this is another isolated case or an emerging phenomenon in Qatar, awareness of medical and surgical complication that can arise in these individuals is of importance to practicing physicians.

CD133 expression is not restricted to stem cells, and both CD133+ and CD133- metastatic colon cancer cells initiate tumors

Colon cancer stem cells are believed to originate from a rare population of putative CD133+ intestinal stem cells. Recent publications suggest that a small subset of colon cancer cells expresses CD133, and that only these CD133+ cancer cells are capable of tumor initiation. However, the precise contribution of CD133+ tumor-initiating cells in mediating colon cancer metastasis remains unknown. Therefore, to temporally and spatially track the expression of CD133 in adult mice and during tumorigenesis, we generated a knockin lacZ reporter mouse (CD133lacZ/+), in which the expression of lacZ is driven by the endogenous CD133 promoters. Using this model and immunostaining, we discovered that CD133 expression in colon is not restricted to stem cells; on the contrary, CD133 is ubiquitously expressed on differentiated colonic epithelium in both adult mice and humans. Using Il10-/-CD133lacZ mice, in which chronic inflammation in colon leads to adenocarcinomas, we demonstrated that CD133 is expressed on a full gamut of colonic tumor cells, which express epithelial cell adhesion molecule (EpCAM). Similarly, CD133 is widely expressed by human primary colon cancer epithelial cells, whereas the CD133- population is composed mostly of stromal and inflammatory cells. Conversely, CD133 expression does not identify the entire population of epithelial and tumor-initiating cells in human metastatic colon cancer. Indeed, both CD133+ and CD133- metastatic tumor subpopulations formed colonospheres in in vitro cultures and were capable of long-term tumorigenesis in a NOD/SCID serial xenotransplantation model. Moreover, metastatic CD133- cells form more aggressive tumors and express typical phenotypic markers of cancer-initiating cells, including CD44 (CD44+CD24-), whereas the CD133+ fraction is composed of CD44lowCD24+ cells. Collectively, our data suggest that CD133 expression is not restricted to intestinal stem or cancer-initiating cells, and during the metastatic transition, CD133+ tumor cells might give rise to the more aggressive CD133(- )subset, which is also capable of tumor initiation in NOD/SCID mice.