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Background: Polymorphisms in FcγRIIa and FcγRIIIa receptors are associated with responses to the CD20-directed immunoglobulin G1 (IgG1) monoclonal antibody rituximab among patients with indolent lymphoma. At odds with the aforementioned clinical observations has been the finding that IgG1 binding is impacted by polymorphisms in FcγRIIIa but not FcγRIIa. One possibility for this discrepancy might involve linkage of polymorphisms between FcγRIIa and FcγRIIIa. Materials and Methods: As such, we performed allelespecific polymerase chain reaction and directed sequencing of the genomic DNA coding region of FcγRIIA and FcγRIIIA for 52 healthy individuals. Results: Two common polymorphisms were observed for FcγRIIA (at positions 27 and 131) and FcγRIIIA (at positions 48 and 158). Importantly, we observed linkage among polymorphisms within and between FcγRIIa and FcγRIIIa, including the expression of histidine at FcγRIIa-131 and valine at FcγRIIIa, both of which are associated with enhanced responses to rituximab. The results of these studies demonstrate that there is wide linkage within and between polymorphisms in FcγRIIa and FcγRIIIa and might provide an explanation for why polymorphisms at FcγRIIa are associated with rituximab responses despite a lack of impact on IgG1 binding. Conclusion: Knowledge of such linkages could facilitate the development of diagnostic tests aimed at identifying patients who might be more suitable for treatment with rituximab and possibly other therapeutic antibodies. [ABSTRACT FROM AUTHOR]

A nationwide survey of adoption agencies was conducted to examine their policies, practices, and attitudes with regard to lesbian and gay prospective adoptive parents. A total of 214 questionnaires were received, representing a return rate of 26 percent. Sixty-three percent of respondents indicated that their agency accepted applications from lesbian and gay individuals, and nearly 38 percent indicated that their agency had made at least one adoption placement with a lesbian or gay adult during the two-year period under study. Attitudes and practices regarding adoption by lesbian and gay individuals varied as a function of the religious affiliation (if any) of the agency, the type of children the agency predominantly placed for adoption, and the gender of the respondent. Overall, the results reveal that, while policies, practices, and attitudes vary across agencies, many adoption professionals are willing to work with lesbian and gay prospective parents, and, in fact, a substantial number have experience in doing so. [ABSTRACT FROM AUTHOR]

Objective. This study compared the networks of extended family and friendship relationships of children conceived via donor insemination with lesbian versus heterosexual parents. Design. Eighty families participated; 55 of the families were headed by lesbian parents and 25 were headed by heterosexual parents. Parents reported their children's contact with grandparents and other important adults. Results. Most children had regular contact with grandparents, other relatives, and adult nonrelatives outside their immediate households, and there were no differences in this regard as a function of parental sexual orientation. Both children of lesbian and heterosexual parents had more frequent contact with the parents of their biological mother than with the parents of their father or other mother. Conclusions. Contrary to negative stereotypes, children of lesbian mothers were described as having regular contact with grandparents. Regardless of parental sexual orientation, children were described as being in more frequent contact with grandparents to whom they were biologically linked. [ABSTRACT FROM AUTHOR]

Background. Radiotherapy is widely used in the management of lung cancer but there are few data on its use in elderly patients. Methods. Retrospective review of case notes of all patients aged 75 years and over referred to a regional centre for radiotherapy with a diagnosis of lung cancer over 1 year. Results. Of 149 patients referred, full information was available on 144 (97%); age range 75-93 years (mean 79). Main referral sources were chest physicians [68 (44%)], general physicians [40 (28%)] and geriatricians [20 (14%)]; all patients were accepted for radiotherapy. One hundred and thirty-four (93%) had palliative treatment with most [129 (90%)] receiving 1-5 fractions over 1 week and 117 (81%) having treatment as an outpatient. Palliation appeared good for haemoptysis but less effective for the more common symptoms of dyspnoea and cough. Side effects were reported by 25 patients (18%) and were usually mild. Conclusion. Radiotherapy for lung cancer in this selected group of elderly patients is well tolerated with responses similar to those in younger patients. [ABSTRACT FROM AUTHOR]

Abstract: Concurrent Bruton tyrosine kinase and BCL2 inhibition has not yet been investigated in Waldenström macroglobulinemia (WM). We performed an investigator-initiated trial of ibrutinib and venetoclax in symptomatic treatment-naïve patients with MYD88-mutated WM. Patients received ibrutinib 420 mg once daily (cycle 1), followed by a ramp-up of venetoclax to 400 mg daily (cycle 2). The combination was then administered for 22 additional 4-week cycles. The attainment of very good partial response (VGPR) was the primary end point. Forty-five patients were enrolled in this study. The median baseline characteristics were as follows: age 67 years, serum IgM 43 g/L, and hemoglobin 102 g/L. Seventeen patients (38%) carried CXCR4 mutations. Nineteen patients (42%) achieved VGPR. Grade 3 or higher adverse events included neutropenia (38%), mucositis (9%), and tumor lysis syndrome (7%). Atrial fibrillation occurred in 3 (9%), and ventricular arrhythmia in 4 (9%) patients that included 2 grade 5 events. With a median follow-up of 24.4 months, the 24-month progression-free survival (PFS) and overall survival (OS) rates were 76% and 96%, respectively, and were not impacted by CXCR4 mutations. The median time on therapy was 10.2 months, and the median time after the end of therapy (EOT) was 13.3 months. Eleven of the 12 progression events occurred after EOT, and the 12-month PFS rates after EOT were 79%; 93% if VGPR was attained, and 69% for other patients (P = .12). Ibrutinib and venetoclax induced high VGPR rates and durable responses after EOT, although they were associated with a higher-than-expected rate of ventricular arrhythmia in patients with WM, leading to early study treatment termination. This trial was registered at www.clinicaltrials.gov as #NCT04273139., (© 2024 American Society of Hematology. Published by Elsevier Inc. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Space weather has the potential to impact ground-based technologies on Earth, affecting many systems including railway signalling. This study uses a recently developed model to analyse the impact of geomagnetically induced currents on railway signalling systems in the United Kingdom during the March 1989 and October 2003 geomagnetic storms. The March 1989 storm is also scaled to estimate a 1-in-100 year and a 1-in-200 year extreme storm. Both the Glasgow to Edinburgh line, and the Preston to Lancaster section of the West Coast Main Line are modelled. No "right side" failures (when unoccupied sections appear occupied) are suggested to have occurred during either storm, and the total number of potential "wrong side" failures (when occupied sections appear clear) is low. However, the modelling indicates "right side" and "wrong side" failures are possible on both routes during the 1-in-100 year and 1-in-200 year extreme storms, with the Glasgow to Edinburgh line showing more total misoperations than the Preston to Lancaster section of the West Coast Main Line. A 1-in-100 year or 1-in-200 year extreme storm would result in misoperations over an extended period of time, with most occurring over a duration of 2-3 h either side of the peak of the storm., (© 2024. The Author(s).)

This article memorializes E. Mavis Hetherington (1926-2023), an eminent developmental psychologist who made major contributions to understanding of children's development. Best known for her longitudinal studies on the impact of divorce on children and families, Hetherington published and lectured widely. Her interests spanned personality and social development, child psychopathology, stress and coping in families, and related topics. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Planning for marriage and childbearing is an important part of many young adults' lives. In this study, we investigated ways in which ideas about family formation among Chinese international students were associated with personal, interpersonal, and cultural factors. In total, 265 childless Chinese international students ( M age = 23 years; all cisgender) in the United States participated in an online survey; 210 self-identified as heterosexual and 55 as sexual minority individuals. Results showed that sexual minority students chose older ideal ages for marriage and parenthood than did heterosexual students. Moreover, sexual minority students were more likely to see the United States and other regions where same-sex marriage is legal as ideal places to live after marriage, but heterosexual students were more likely to describe China as ideal. In reality, however, many students expected to return home to China, and there were no differences in their expectations as a function of sexual identities. In addition, students who reported greater acculturation to culture of the United States were more likely to choose the United States as the ideal place to live. Students who endorsed the importance of filial piety and who perceived more support from family were more likely to view China as the ideal place to live. Finally, sexual minority students who wanted to become parents chose a greater variety of pathways to parenthood than did heterosexual students. Results highlighted the role of sexual orientation, social support, and cultural ideals in shaping the ways Chinese students thought about future families. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Background: Advanced practice providers (APPs) play important roles in enrolling, educating, and caring for patients in clinical trials. However, much remains unknown about the role of APPs in managing adverse events (AEs) in early (phase I to II) clinical trials. In this study, we assessed the outpatient management of grade 3 to 4 AEs by APPs in early trials and characterized the workflow of our APP Phase I to II Fast Track (FT) Clinic., Patients and Methods: We retrospectively reviewed records of patients with advanced or metastatic solid tumors enrolled in phase I to II clinical trials who were seen by APPs from September 2017 to August 2018 in the APP phase I to II FT clinic in the Department of Investigational Cancer Therapeutics., Results: A total of 808 patients enrolled in 159 clinical trials were seen in 2,697 visits (median 3 visits per patient; range 1-28) by 10 APPs. Treatment was interrupted in 6.9% of visits, and grade 3 to 4 AEs were seen in 5.4% of visits; however, patients from 1.4% of visits were sent to the emergency center (EC) and/or admitted. Patients referred to the EC and/or admitted were more likely to have baseline hypoalbuminemia, high lactate dehydrogenase, and poor Eastern Cooperative Oncology Group performance status (i.e., ECOG > 1; p < .001). There were no associations between EC referral and gender, APP years of experience, or type of treatment., Conclusions: The APP Phase I to II FT Clinic has an important role in the management of AEs by APPs in early clinical trials in the outpatient setting, potentially avoiding EC visits and admissions., Competing Interests: The authors have no potential conflicts of interest to disclose. This work was partially supported by the National Institutes of Health through MD Anderson Cancer Center’s Support Grant (P30 CA016672) and the NCI K12 Paul Calabresi Award CA088084., (© 2022 Harborside™.)

The SRC family kinase (SFK) HCK is transcriptionally upregulated and activated by mutated MYD88 (MYD88Mut), a key adaptor for Toll-receptor signaling. HCK activates BTK, AKT, and ERK in MYD88Mut lymphomas. SYK, a B-cell receptor (BCR) component, is activated in MYD88Mut lymphoma cells. Although the SFK LYN serves as a trigger for SYK activation in MYD88Mut ABC DLBCL cells, LYN activity is muted in MYD88Mut Waldenstrom macroglobulinemia (WM) cells. We therefore investigated a role for HCK in mediating SYK activation. Overexpression of wild-type (WT) (HCKWT) or gatekeeper mutated (HCKThr333Met) HCK in MYD88Mut lymphoma cells triggered SYK activation. Conversely, HCK knockdown reduced p-SYK in MYD88Mut lymphoma cells. Coimmunoprecipitation experiments showed that HCK was complexed with p-SYK in MYD88Mut BCWM.1 and TMD8 cells, but not in MYD88 WT Ramos cells. Rescue experiments in MYD88Mut lymphoma cells expressing HCKThr333Met led to persistent HCK and SYK activation and resistance to the HCK inhibitor A419259. Treatment of primary MYD88Mut WM cells with A419259 reduced p-HCK and p-SYK expression. Taken together, our findings show that SYK is activated by HCK in MYD88Mut B-cell lymphomas cells, broaden the prosurvival signaling generated by aberrant HCK expression in response to MYD88Mut, and help define HCK as an important therapeutic target in MYD88Mut B-cell lymphomas., (© 2022 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Ibrutinib is highly active and produces long-term responses in patients with Waldenström macroglobulinemia (WM), but acquired resistance can occur with prolonged treatment. We therefore evaluated the natural history and treatment outcomes in 51 WM patients with acquired resistance to ibrutinib monotherapy. The median time between ibrutinib initiation and discontinuation was 2 years (range, 0.4-6.5 years). Following discontinuation of ibrutinib, a rapid increase in serum immunoglobulin M level was observed in 60% (29/48) of evaluable patients, of whom ten acutely developed symptomatic hyperviscosity. Forty-eight patients (94%) received salvage therapy after ibrutinib. The median time to salvage therapy after ibrutinib cessation was 18 days (95% confidence interval [CI]: 13-27). The overall and major response rates to salvage therapy were 56% and 44%, respectively, and the median duration of response was 48 months (95% CI: 34-not reached). Quadruple-class (rituximab, alkylator, proteasome inhibitor, ibrutinib) exposed disease (odds ratio [OR] 0.20, 95% CI: 0.05-0.73) and salvage therapy ≤7 days after discontinuing ibrutinib (OR 4.12, 95% CI: 1.07- 18.9) were identified as independent predictors of a response to salvage therapy. The 5-year overall survival (OS) following discontinuation of ibrutinib was 44% (95% CI: 26-75). Response to salvage therapy was associated with better OS after ibrutinib (hazard ratio 0.08, 95% CI: 0.02-0.38). TP53 mutations were associated with shorter OS, while acquired BTK C481S mutations had no impact. Our findings reveal that continuation of ibrutinib until subsequent treatment is associated with improved disease control and clinical outcomes.

Bruton tyrosine kinase (BTK) inhibitors are the only FDA-approved treatments for Waldenström macroglobulinemia (WM). Factors prognostic of survival and predictive of response to BTK inhibitors remained to be clarified. We evaluated 319 patients with WM to identify predictive and prognostic factors on ibrutinib monotherapy. Logistic and Cox proportional-hazard regression models were fitted for response and survival. Multiple imputation analyses were used to address bias associated with missing data. Major (partial response or better) and deep responses (very good partial response or better) were attained in 78% and 28% of patients. CXCR4 mutations were associated with lower odds of major (odds ratio [OR], 0.2; 95% confidence interval [CI], 0.1-0.5; P < .001) and deep response (OR, 0.3; 95% CI, 0.2-0.6; P = .001). CXCR4 mutations (hazard ratio [HR], 2.0; 95% CI, 1.2-3.4; P = .01) and platelet count 100 K/uL or less (HR, 2.5; 95% CI, 1.3-4.9; P = .007) were associated with worse progression-free survival (PFS). We proposed a scoring system using these 2 factors. The median PFS for patients with 0, 1, and 2 risk factors were not reached, 5 years and 3 years (P < .001). Patients with 2 risk factors had HR 2.2 (95% CI, 1.3-3.8; P = .004) compared with 1 factor, and patients with 1 factor had HR 2.3 (95% CI, 1.1-5.1; P = .03) compared with 0 factors. Age ≥65 years was the only factor associated with overall survival (HR, 3.2; 95% CI, 1.4-7.0; P = .005). Multiple imputation analyses did not alter our results. Our study confirms the predictive and prognostic value of CXCR4 mutations in patients with WM treated with ibrutinib monotherapy., (© 2022 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Herein, we present the final report of a single-center, prospective phase II study evaluating ibrutinib 420 mg once daily in 30 treatment-naive patients with Waldenstrom macroglobulinemia (WM). The present study is registered with ClinicalTrials.Gov (NCT02604511). With a median follow-up of 50 months, the overall, major, and VGPR response rates were 100%, 87%, and 30%. The VGPR rate was numerically but not significantly lower in patients with than without CXCR4 mutations (14% vs. 44%; p = 0.09). The median time to a minor response was 0.9 months, and to a major response was 1.9 months, though were longer in those with mutated CXCR4 at 1.7 months (p = 0.07) and 7.3 months (p = 0.01). Six patients had disease progression. The median progression-free survival (PFS) was not reached, and the 4-year PFS rate was 76%. There was also a non-significant lower 4-year PFS rate in patients with than without CXCR4 mutations (59% vs. 92%; p = 0.06). The most common treatment-related adverse events were fatigue, upper respiratory infection, and hematoma. Atrial fibrillation occurred in 20% of patients. Ibrutinib monotherapy induced durable responses in treatment-naive patients with WM. CXCR4 mutations impacted VGPR attainment, time to major response, and 4-year PFS rate., (© 2021. The Author(s).)

In recent years, many lesbian, gay, bisexual, transgender, and queer (LGBTQ+) adults have become parents. LGBTQ+ parenthood does, however, remain a controversial topic across the United States and around the world. Several questions have been raised. For instance, to what extent do LGBTQ+ adults make capable parents? Do children who have LGBTQ+ parents grow up in healthy ways? What factors contribute to positive family functioning in families with LGBTQ+ parents? A growing body of social science research has addressed these questions, and the findings suggest both that LGBTQ+ adults are successful in their roles as parents and that their children develop in positive ways. Overall, the findings to date suggest that parental sexual orientation and gender identity do not in themselves determine success in parenting or child development; indeed, sexual and gender minority parents and their children have shown remarkable resilience, even in the face of many challenges. Contextual issues, as well as implications of research findings for law and policy around the world are discussed., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Purpose: BCL2 is overexpressed and confers prosurvival signaling in malignant lymphoplasmacytic cells in Waldenström macroglobulinemia (WM). Venetoclax is a potent BCL2 antagonist and triggers in vitro apoptosis of WM cells. The activity of venetoclax in WM remains to be clarified., Patients and Methods: We performed a multicenter, prospective phase II study of venetoclax in patients with previously treated WM (NCT02677324). Venetoclax was dose-escalated from 200 mg to a maximum dose of 800 mg daily for up to 2 years., Results: Thirty-two patients were evaluable, including 16 previously exposed to Bruton tyrosine kinase inhibitors (BTKis). All patients were MYD88 L265P -mutated, and 17 carried CXCR4 mutations. The median time to minor and major responses was 1.9 and 5.1 months, respectively. Previous exposure to BTKis was associated with a longer time to response (4.5 v 1.4 months; P < .001). The overall, major, and very good partial response rates were 84%, 81%, and 19%, respectively. The major response rate was lower in those with refractory versus relapsed disease (50% v 95%; P = .007). The median follow-up time was 33 months, and the median progression-free survival was 30 months. CXCR4 mutations did not affect treatment response or progression-free survival. The only recurring grade ≥ 3 treatment-related adverse event was neutropenia (n = 14; 45%), including one episode of febrile neutropenia. Laboratory tumor lysis without clinical sequelae occurred in one patient. No deaths have occurred., Conclusion: Venetoclax is safe and highly active in patients with previously treated WM, including those who previously received BTKis. CXCR4 mutation status did not affect treatment response., Competing Interests: Jorge J. CastilloConsulting or Advisory Role: Janssen, Roche/Genentech, Beigene, AbbVie/PharmacyclicsResearch Funding: Pharmacyclics (Inst), AbbVie (Inst), Janssen (Inst), BeiGene (Inst), TG Therapeutics (Inst) John N. AllanHonoraria: AstraZeneca, AbbVie, Pharmacyclics/Janssen, BeiGeneConsulting or Advisory Role: AbbVie/Genentech, Pharmacyclics, Ascentage Pharma, BeiGene, Janssen Oncology, Epizyme, AstraZeneca, TG Therapeutics, ADC TherapeuticsResearch Funding: Genentech, Janssen, Celgene, TG Therapeutics Tanya SiddiqiConsulting or Advisory Role: Juno Therapeutics, AstraZeneca, BeiGene, Celgene, Pharmacyclics, Bristol Myers Squibb/CelgeneSpeakers' Bureau: Pharmacyclics/Janssen, AstraZeneca, BeiGene, Bristol Myers Squibb/CelgeneResearch Funding: Juno Therapeutics (Inst), Kite, a Gilead company (Inst), Acerta Pharma (Inst), TG Therapeutics (Inst), BeiGene (Inst), Pharmacyclics (Inst), Celgene (Inst), Oncternal Therapeutics (Inst), Bristol-Myers Squibb/Sanofi (Inst) Ranjana H. AdvaniConsulting or Advisory Role: Genentech/Roche, Seattle Genetics, Takeda, Portola Pharmaceuticals, Celgene, Sanofi, Kura Oncology, Merck, Karyopharm Therapeutics, ADC Therapeutics, Daiichi Sankyo, Bristol Myers Squibb/Celgene, Epizyme, IncyteResearch Funding: Millennium (Inst), Seattle Genetics (Inst), Genentech/Roche (Inst), Pharmacyclics (Inst), Janssen (Inst), Merck (Inst), Kura Oncology (Inst), Forty Seven (Inst), Cyteir (Inst) Catherine A. FlynnConsulting or Advisory Role: Pharmacyclics, Karyopharm Therapeutics Shayna SarosiekResearch Funding: Acrotech Biopharma (Inst) Andrew R. BranaganConsulting or Advisory Role: Pharmacyclics/Janssen, Genzyme, Adaptive Biotechnologies, BeiGene, Karyopharm Therapeutics, CSL Behring Xia LiuEmployment: Merck (I) Guang YangEmployment: AbbVie (I), Blueprint MedicinesStock and Other Ownership Interests: Blueprint MedicinesHonoraria: Janssen Matthew S. DavidsHonoraria: Research to PracticeConsulting or Advisory Role: Genentech, Janssen, Pharmacyclics, TG Therapeutics, AbbVie, AstraZeneca, Celgene, MEI Pharma, Adaptive Biotechnologies, Verastem, Ascentage Pharma, BeiGene, Lilly, Novartis, Takeda, Bristol Myers SquibbResearch Funding: Genentech (Inst), TG Therapeutics (Inst), Pharmacyclics (Inst), Surface Oncology (Inst), MEI Pharma (Inst), Verastem (Inst), Ascentage Pharma (Inst), AstraZeneca (Inst), Novartis (Inst)Travel, Accommodations, Expenses: TG Therapeutics, Janssen, AbbVie, BeiGene, Genentech Richard R. FurmanHonoraria: Janssen, AstraZeneca, Pharmacyclics, Janssen Biotech, Genentech/Roche, Loxo, TG Therapeutics, Verastem, Acerta Pharma, AstraZeneca, Beigene, Incyte, OncoTracker, AbbVie, MorphoSys, SanofiResearch Funding: Acerta Pharma, TG TherapeuticsExpert Testimony: AbbVie, Janssen OncologyTravel, Accommodations, Expenses: TG Therapeutics, Janssen OncologyOther Relationship: Incyte, Janssen Biotech Steven P. TreonHonoraria: Abbvie/Pharmacyclics, Janssen Oncology, BeiGeneConsulting or Advisory Role: Janssen, Pharmacyclics, Beigene, X4 Pharmaceuticals, Bristol Myers SquibbResearch Funding: Pharmacyclics, Bristol Myers Squibb (Inst), X4 Pharmaceuticals (Inst), Lilly (Inst), Beigene (Inst), AbbVie (Inst)Patents, Royalties, Other Intellectual Property: My institution holds patents related to use of MYD88 and CXCR4 testing for which a predetermined financial distribution to the laboratory and individuals is provided. I have not received any income to this date related to these patents (Inst)Travel, Accommodations, Expenses: Janssen OncologyOther Relationship: Janssen, Pharmacyclics, BeigeneNo other potential conflicts of interest were reported.

Activating mutations in MYD88 promote malignant cell growth and survival through hematopoietic cell kinase (HCK)-mediated activation of Bruton tyrosine kinase (BTK). Ibrutinib binds to BTKCys481 and is active in B-cell malignancies driven by mutated MYD88. Mutations in BTKCys481, particularly BTKCys481Ser, are common in patients with acquired ibrutinib resistance. We therefore performed an extensive medicinal chemistry campaign and identified KIN-8194 as a novel dual inhibitor of HCK and BTK. KIN-8194 showed potent and selective in vitro killing of MYD88-mutated lymphoma cells, including ibrutinib-resistant BTKCys481Ser-expressing cells. KIN-8194 demonstrated excellent bioavailability and pharmacokinetic parameters, with good tolerance in rodent models at pharmacologically achievable and active doses. Pharmacodynamic studies showed sustained inhibition of HCK and BTK for 24 hours after single oral administration of KIN-8194 in an MYD88-mutated TMD-8 activated B-cell diffuse large B-cell lymphoma (ABC DLBCL) and BCWM.1 Waldenström macroglobulinemia (WM) xenografted mice with wild-type BTK (BTKWT)- or BTKCys481Ser-expressing tumors. KIN-8194 showed superior survival benefit over ibrutinib in both BTKWT- and BTKCys481Ser-expressing TMD-8 DLBCL xenografted mice, including sustained complete responses of >12 weeks off treatment in mice with BTKWT-expressing TMD-8 tumors. The BCL&#95;2 inhibitor venetoclax enhanced the antitumor activity of KIN-8194 in BTKWT- and BTKCys481Ser-expressing MYD88-mutated lymphoma cells and markedly reduced tumor growth and prolonged survival in mice with BTKCys481Ser-expressing TMD-8 tumors treated with both drugs. The findings highlight the feasibility of targeting HCK, a key driver of mutated MYD88 pro-survival signaling, and provide a framework for the advancement of KIN-8194 for human studies in B-cell malignancies driven by HCK and BTK., (© 2021 by The American Society of Hematology.)

MYD88 and CXCR4 mutations are common in Waldenström macroglobulinemia (WM). Mutated CXCR4 (CXCR4Mut) impacts BTK-inhibitor response. We conducted a phase 1 trial of the CXCR4-antagonist ulocuplumab with ibrutinib in this first-ever study to target CXCR4Mut in WM. Ibrutinib was initiated at 420 mg/d with cycle 1 and continued until intolerance or progression; ulocuplumab was given cycles 1 to 6, with a 3 + 3 dose-escalation design. Each cycle was 4 weeks. Thirteen symptomatic patients, of whom 9 were treatment-naive patients were enrolled. Twelve were evaluable for response. At best response, their median serum immunoglobulin M declined from 5574 to 1114 mg/dL; bone marrow disease decreased from 65% to 10%, and hemoglobin increased from 10.1 to 14.2 g/dL (P < .001). The major and VGPR response rates were 100% and 33%, respectively, with VGPRs observed at lower ulocuplumab dose cohorts. Median times to minor and major responses were 0.9 and 1.2 months, respectively. With a median follow-up of 22.4 months, the estimated 2-year progression-free survival was 90%. The most frequent recurring grade ≥2 adverse events included reversible thrombocytopenia, rash, and skin infections. Ulocuplumab dose-escalation did not impact adverse events. The study demonstrates the feasibility of combining a CXCR4-antagonist with ibrutinib and provides support for the development of CXCR4-antagonists for CXCR4Mut WM. This trial was registered at www.clinicaltrials.gov as #NCT03225716., (© 2021 by The American Society of Hematology.)

CXCR4 mutations impact disease presentation and treatment outcomes in Waldenström macroglobulinaemia (WM). Non-uniform testing for CXCR4 mutations may account for discordant findings in WM clinical trials. We compared two approaches used in these trials for detection of the most common CXCR4 (S338X) variant: targeted next-generation sequencing (NGS) using unselected bone marrow (BM) samples, and combined allele-specific polymerase chain reaction (AS-PCR) and Sanger sequencing with unselected and CD19-selected BM samples. Our findings showed that targeted NGS frequently yielded false-negative results. Both CD19 selection and AS-PCR markedly improved detection of CXCR4 S338X mutations. Sensitivity was adversely impacted by low BM involvement and CXCR4 mutation clonality., (© 2021 British Society for Haematology and John Wiley & Sons Ltd.)

Purpose: We report the long-term findings and final analysis of a pivotal multicenter trial of ibrutinib monotherapy in previously treated patients with Waldenström macroglobulinemia (WM)., Patients and Methods: Sixty-three symptomatic patients with median prior therapies of two (range, one to nine therapies), of whom 40% were refractory to their previous therapy, received ibrutinib at 420 mg/d. Dose reduction was permitted for toxicity., Results: The median follow-up was 59 months, and overall and major response rates were 90.5% and 79.4%, respectively. At best response, median serum immunoglobulin M declined from 3,520 to 821 mg/dL, bone marrow disease involvement declined from 60% to 20%, and hemoglobin rose from 10.3 to 14.2 g/dL ( P < .001 for all comparisons). Responses were impacted by mutated (Mut) MYD88 and CXCR4 status. Patients with MYD88 Mut , wild-type (WT) CXCR4 showed higher major (97.2% v 68.2%; P < .0001) and very good partial (47.2% v 9.1%; P < .01) response rates and a shorter time to major response (1.8 v 4.7 months; P = .02) versus patients with MYD88 Mut CXCR4 Mut . Conversely, four patients who had MYD88 WT disease showed no major responses. The median 5-year progression-free survival (PFS) rate for all patients was not reached, and was 70% and 38% for those with MYD88 Mut CXCR4 WT and MYD88 Mut CXCR4 Mut WM, respectively ( P = .02). In patients with MYD88 WT , the median PFS was 0.4 years ( P < .01 for three-way comparisons). The 5-year overall survival rate for all patients was 87%. Grade ≥ 3 adverse events in more than one patient at least possibly related included neutropenia (15.9%), thrombocytopenia (11.1%), and pneumonia (3.2%). Eight patients (12.7%) experienced atrial arrhythmia, and seven of the eight continued therapy with medical management., Conclusion: Ibrutinib is highly active and produces long-term disease control in previously treated patients with WM. Treatment is tolerable. Response depth, time to major response, and PFS are impacted by MYD88 and CXCR4 mutation status.

Proteasome inhibition is a standard of care for the primary treatment of patients with Waldenström macroglobulinemia (WM). We present the long-term follow-up of a prospective, phase II clinical trial that evaluated the combination of ixazomib, dexamethasone, and rituximab (IDR) in 26 treatment-naive patients with WM. IDR was administered as 6 monthly induction cycles followed by 6 every-2-month maintenance cycles. The MYD88 L265P mutation was detected in all patients, and CXCR4 mutations were detected in 15 patients (58%). The median time to response (TTR) and time to major response (TTMR) were 2 and 6 months, respectively. Patients with and without CXCR4 mutations had median TTR of 3 months and 1 month, respectively (P = .003), and median TTMR of 10 months and 3 months, respectively (P = .31). The overall, major, and very good partial response (VGPR) rates were 96%, 77%, and 19%, respectively. The rate of VGPR in patients with and without CXCR4 mutations were 7% and 36%, respectively (P = .06). The median progression-free survival (PFS) was 40 months, the median duration of response (DOR) was 38 months, and the median time to next treatment (TTNT) was 40 months. PFS, DOR, and TTNT were not affected by CXCR4 mutational status. The safety profile was excellent with no grade 4 adverse events or deaths to date. IDR provides a safe and effective frontline treatment option for symptomatic patients with WM. This study was registered at www.clinicaltrials.gov as #NCT02400437., (© 2020 by The American Society of Hematology.)

Cases of non-IgM lymphoplasmacytic lymphoma (LPL) are rare. We performed a case-control study comparing features and outcomes of 31 non-IgM LPL cases and 93 Waldenström macroglobulinemia (WM) controls matched by age, sex, and year of diagnosis. Odds of MYD88 mutations were lower (odds ratio (OR) 0.22, p  = .05), and median time to treatment was shorter in cases than in controls (4 vs. 32 months; p  < .001). Odds of extramedullary disease were higher (OR 4.20, p  = .01), while odds of neuropathy (OR 0.22, p  = .25), and hyperviscosity (OR 0.26, p  = .26) were lower in cases than in controls. Odds of using chemoimmunotherapy were higher (OR 2.62, p  = .11) while odds of using proteasome inhibitors (OR 0.35, p  = .15) and BTK inhibitors (OR 0.17, p  = .21) were lower in cases than in controls. There were no differences in response and overall survival (OS) between cases and controls. Despite clinicopathological differences, response, and survival outcomes are similar between non-IgM LPL cases and WM controls.

Ibrutinib is the first approved therapy for symptomatic patients with Waldenström macroglobulinemia (WM). The approval was based on a single, multicenter, phase II trial in previously treated WM patients. We sought to evaluate whether there were differences in clinical characteristics, response, and survival outcomes to ibrutinib monotherapy between WM patients treated on and off clinical trials. Treatment naïve and previously treated patients who received ibrutinib monotherapy at our institution and participated in two prospective studies (ON trial; n = 72) or a prospective database (OFF trial; n = 157) were included. The median times from WM diagnosis to ibrutinib initiation were 3.1 and 3.5 years for ON and OFF trial patients, respectively (p = 0.38). Similar rates of categorical response at 6, 12, and 24 months and at best response were also observed between ON trial and OFF trial patients. The 4-year PFS and OS rates for ON trial and OFF trial patients were 72% and 63%, respectively (log-rank p = 0.14) and 83% and 81%, respectively (log-rank p = 0.14). CXCR4 mutations impacted response and survival outcomes to ibrutinib monotherapy. The 4-year rates of ibrutinib discontinuation in ON and OFF trial patients were 36% and 44%, respectively (p = 0.11). Ibrutinib is effective in the routine clinical care of both treatment-naïve and previously treated WM patients. The findings of our study validate the efficacy of ibrutinib monotherapy reported in multiple phase II clinical trials., (Copyright © 2020 the Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the European Hematology Association.)

Next-generation sequencing has revealed recurring somatic mutations in Waldenström macroglobulinemia (WM), including MYD88 (95%-97%), CXCR4 (30%-40%), ARID1A (17%), and CD79B (8%-15%). Deletions involving chromosome 6q are common in patients with mutated MYD88 and include genes that modulate NFKB, BCL2, Bruton tyrosine kinase (BTK), and apoptosis. Patients with wild-type MYD88 WM show an increased risk of transformation and death and exhibit many mutations found in diffuse large B-cell lymphoma. The discovery of MYD88 and CXCR4 mutations in WM has facilitated rational drug development, including the development of BTK and CXCR4 inhibitors. Responses to many agents commonly used to treat WM, including the BTK inhibitor ibrutinib, are affected by MYD88 and/or CXCR4 mutation status. The mutation status of both MYD88 and CXCR4 can be used for a precision-guided treatment approach to WM.

Rituximab-containing regimens are commonly used for frontline therapy in patients with symptomatic Waldenström macroglobulinemia (WM). We had observed that a portion of WM patients experienced deepening of response months to years after therapy completion. We carried a retrospective study aimed at describing this phenomenon. We gathered baseline data, and responses at end of induction, end of maintenance and best response. Deepening of response was defined as ≥25% decrease in serum IgM achieved at a later time from therapy completion. Of 178 patients included, 116 (65%) received maintenance therapy and 62 (35%) were observed. In patients who received maintenance, 44 (38%) had ≥25% decrease in serum IgM level after the end of maintenance with a median time from end of maintenance to lowest IgM level of 1.6 years (range 0.1-7.9 years). In patients who were observed, 19 (31%) had ≥25% decrease in serum IgM level after the end of induction with a median time from end of induction to lowest IgM level of 1.6 years (range 0.2-5.1 years). Baseline hemoglobin <11.5 g/dL, bone marrow involvement ≥50%, CXCR4 mutations and serum IgM ≥4000 mg/dL were associated with lower odds of deepening of response after therapy completion. Deepening of response was associated with better progression-free survival (PFS; HR 0.46, 95% CI 0.26-0.80; P = .006) and better survival after frontline treatment initiation (SAFTI; HR 0.21, 95% CI 0.06-0.73; P = .01). In conclusion, deepening of response occurs in one third of WM patients after completing rituximab-containing regimens and was associated with better PFS and SAFTI., (© 2019 Wiley Periodicals, Inc.)

Activating MYD88 mutations promote pro-survival signaling through BTK and HCK, both targets of ibrutinib. Despite high response rates, complete responses to ibrutinib are lacking, and other MYD88 triggered pro-survival pathways may contribute to primary drug resistance. B-cell receptor (BCR) signaling has been observed in lymphomas driven by mutated MYD88, even without activating the BCR pathway mutations. We identified activated SYK (p-SYK), a component of BCR in complex with MYD88 in MYD88-mutated WM and ABC DLBCL lymphoma cells. Confocal microscopy confirmed co-localization of MYD88 with SYK in MYD88-mutated cells. Knockdown of MYD88 or use of a MYD88 signaling inhibitor abrogated SYK activation, while expression of mutated but not wild-type MYD88 amplified p-SYK in MYD88-mutated and wild-type lymphoma cells. Knockdown of SYK or use of inhibitors targeting SYK blocked p-STAT3 and p-AKT signaling in MYD88-mutated cells. Cell viability analysis showed that combining ibrutinib and SYK inhibitors triggered synthetic killing of MYD88-mutated lymphoma cells. Our findings extend the spectrum of mutated MYD88 pro-survival signaling to include SYK directed BCR cross talk in MYD88-mutated lymphomas. Targeting SYK in combination with ibrutinib produces synthetic lethality, providing a framework for the clinical investigation of ibrutinib with SYK inhibitors in MYD88-mutated lymphomas.

Hematopoietic cell kinase (HCK) is an SRC family member that is aberrantly upregulated in B-cell neoplasms dependent on MYD88-activating mutations and supports their growth and survival. We showed herein that activation of Toll-like receptor (TLR) signaling in MYD88 wild-type B cells also triggered HCK expression, denoting on path regulatory function for HCK by MYD88. To clarify the signaling cascades responsible for aberrant HCK expression in MYD88-mutated B-cell lymphomas, we performed promoter-binding transcription factor (TF) profiling, PROMO weighted TF consensus binding motif analysis, and chromatin immunoprecipitation studies. We identified PAX5, and the mutated MYD88 downstream signaling mediators STAT3, NF-κB, and AP-1, as important drivers of HCK transcription. Knockdown of PAX5, a crucial regulatory factor required for B-cell commitment and identity, abrogated HCK transcription in MYD88-mutated lymphoma cells. Among AP-1 complex components, JunB showed greatest relevance to TLR/MYD88 signaling and HCK transcription regulation. In MYD88-mutated Waldenström macroglobulinemia and activated B-cell-diffuse large B-cell lymphoma cells, knockdown of MYD88 reduced phosphorylation of JunB but not c-Jun, and knockdown of JunB reduced HCK protein levels. Deletion of STAT3, NF-κB, and AP-1 binding sites reduced corresponding TFs binding and HCK promoter activity. Moreover, inhibitors to STAT3, NF-κB, and AP-1 reduced HCK promoter activity and messenger RNA levels, particularly in combination, in MYD88-mutated lymphoma cells. The findings provide new insights into the transcriptional regulation of HCK prosurvival signaling by mutated MYD88, and the importance of JunB as a downstream mediator of the MYD88-directed signaling apparatus., (© 2020 by The American Society of Hematology.)