Chronic lymphocytic leukaemia

Aberrantly expressed Wnt5a in nurse-like cells drives resistance to Venetoclax in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of neoplastic B lymphocytes with high levels of Wnt5a in the plasma. Currently, the cell source of Wnt5a remains controversial. The receptor of Wnt5a is ROR1, whose expression is associated with disease progression and resistance to venetoclax, a BCL-2 inhibitor approved for the treatment of CLL. In this study, we found that the levels of Wnt5a in the plasma of CLL patients were positively correlated with absolute monocyte counts, but not lymphocyte counts. We cultured monocyte-derived nurse-like cells (NLCs) from patients with CLL, and detected Wnt5a expressed in NLCs. Flow cytometry and transwell assays showed that the antibody neutralizing Wnt5a inhibited the enhanced survival and migration in CLL cells co-cultured with NLCs. Furthermore, we performed a drug screening with CLL cells cultured with or without NLCs with a library containing 133 FDA-approved oncology drugs by using high-throughput flow cytometry. We observed a significant resistance to venetoclax in CLL cells co-cultured with NLCs. Immunoblot revealed the activation of NF-κB with enhanced expression of MCL-1 and BCL-XL in CLL cells co-cultured with NLCs. Neutralizing Wnt5a or blocking NF-κB pathway significantly decreased the expression of MCL-1 and BCL-XL, which leads to enhanced sensitivity to venetoclax in CLL cells co-cultured with NLCs. In conclusion, our data showed that NLCs could be one of the sources of Wnt5a detected in patients with CLL, and Wnt5a-induced NF-κB activation in the CLL microenvironment results in resistance to venetoclax in CLL cells.

Natural Killer Cell-Mediated Immunotherapy for Leukemia

Simple Summary

Conventional therapies such as chemotherapy and radiation in leukemia increase infection susceptibility, adverse side effects and immune cell inactivation. Natural killer (NK) cells are the first line of defense against cancer and are critical in the recognition and cytolysis of rapidly dividing and abnormal cell populations. In this review, we describe NK cells and NK cell receptors, functional impairment of NK cells in leukemia, NK cell immunotherapies currently under investigation including monoclonal antibodies (mAbs), adoptive transfer, chimeric antigen receptor-NKs (CAR-NKs), bi-specific/tri-specific killer engagers (BiKEs/TriKEs) and potential targets of NK cell-mediated immunotherapy for leukemia in the future.

Abstract

Leukemia is a malignancy of the bone marrow and blood resulting from the abnormal differentiation of hematopoietic stem cells (HSCs). There are four main types of leukemia including acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), chronic myeloid leukemia (CML), and chronic lymphocytic leukemia (CLL). While chemotherapy and radiation have been conventional forms of treatment for leukemia, these therapies increase infection susceptibility, adverse side effects and immune cell inactivation. Immunotherapies are becoming promising treatment options for leukemia, with natural killer (NK) cell-mediated therapy providing a specific direction of interest. The role of NK cells is critical for cancer cell elimination as these immune cells are the first line of defense against cancer proliferation and are involved in both recognition and cytolysis of rapidly dividing and abnormal cell populations. NK cells possess various activating and inhibitory receptors, which regulate NK cell function, signaling either inhibition and continued surveillance, or activation and subsequent cytotoxic activity. In this review, we describe NK cells and NK cell receptors, functional impairment of NK cells in leukemia, NK cell immunotherapies currently under investigation, including monoclonal antibodies (mAbs), adoptive transfer, chimeric antigen receptor-NKs (CAR-NKs), bi-specific/tri-specific killer engagers (BiKEs/TriKEs) and future potential targets of NK cell-based immunotherapy for leukemia.

Characterization of real-world treatment practices and outcomes among patients with chronic lymphocytic leukemia treated in a Finnish tertiary center

Objectives

We conducted this retrospective study to characterize the change in chronic lymphocytic leukemia (CLL) treatment patterns between 2005 and 2019, to understand the treatment sequencing across the course of the disease, and to investigate how targeted agents and prognostic testing were implemented into the patient care.

Methods

This study included adult patients with CLL treated at the Hospital District of Southwest Finland during the study period. Data were collected from the Turku University Hospital data lake.

Results

In total, 122 and 60 patients received first- and second-line treatments for CLL, respectively. The shift from conventional chemoimmunotherapy to targeted treatments in recent years (2014-2019) was observed. The median overall survival times were not reached in patients treated with targeted agents compared to conventional standard treatments in first- and second-line settings and improved toward the end of the study period. Prognostic testing increased during the study follow-up and patients with unmutated immunoglobulin heavy-chain variable showed significantly poorer overall survival and time-to-next-treatment outcomes than patients with mutated immunoglobulin heavy-chain variable.

Conclusions

This real-world study implicated added value of targeted chemo-free therapies as reported in randomized clinical trials, and highlighted the necessity of prognostic testing in order to improve treatment selection and patient outcomes.

Utilization of CRISPR-Mediated Tools for Studying Functional Genomics in Hematological Malignancies: An Overview on the Current Perspectives, Challenges, and Clinical Implications

Hematological malignancies (HM) are a group of neoplastic diseases that are usually heterogenous in nature due to the complex underlying genetic aberrations in which collaborating mutations enable cells to evade checkpoints that normally safeguard it against DNA damage and other disruptions of healthy cell growth. Research regarding chromosomal structural rearrangements and alterations, gene mutations, and functionality are currently being carried out to understand the genomics of these abnormalities. It is also becoming more evident that cross talk between the functional changes in transcription and proteins gives the characteristics of the disease although specific mutations may induce unique phenotypes. Functional genomics is vital in this aspect as it measures the complete genetic change in cancerous cells and seeks to integrate the dynamic changes in these networks to elucidate various cancer phenotypes. The advent of CRISPR technology has indeed provided a superfluity of benefits to mankind, as this versatile technology enables DNA editing in the genome. The CRISPR-Cas9 system is a precise genome editing tool, and it has revolutionized methodologies in the field of hematology. Currently, there are various CRISPR systems that are used to perform robust site-specific gene editing to study HM. Furthermore, experimental approaches that are based on CRISPR technology have created promising tools for developing effective hematological therapeutics. Therefore, this review will focus on diverse applications of CRISPR-based gene-editing tools in HM and its potential future trajectory. Collectively, this review will demonstrate the key roles of different CRISPR systems that are being used in HM, and the literature will be a representation of a critical step toward further understanding the biology of HM and the development of potential therapeutic approaches.

The global burden and attributable risk factors of chronic lymphocytic leukemia in 204 countries and territories from 1990 to 2019: analysis based on the global burden of disease study 2019

Background

Chronic lymphocytic leukemia (CLL) is the most prevalent subtype of leukemia in Western countries, causing a substantial health burden on patients and society. Comprehensive evaluation of the epidemiological characteristics of CLL is warranted, especially in the current context of global population aging. The main objective of this study is evaluating the disease burden of CLL at global, regional, and national levels from 1990 to 2019. As secondary objectives, we studied the influence of demographic factors and performed risk factor analysis. We hope this study could provide evidence for the evaluation of the effectiveness of previous prevention strategies and the formulation of future global health policies.

Results

Based on data of CLL between 1990 to 2019 from the Global Burden of Disease (GBD) study 2019, we depicted the age, gender, and regional structure of the CLL burden population and described the impact of social development on the disease burden of CLL. The distribution and changing trends of attributable risk factors were also investigated. The global burden of CLL has increased dramatically. A high incidence has been achieved in males and elder people. Countries and territories with high social-demographic index (SDI) tended to have higher global burden than low-SDI region. Of risk factors, high body mass index and smoking were the major contributors for CLL-related mortality and disability adjusted life-years (DALYs).

Conclusion

In summary, the global CLL burden continues to rise over the past 30 years. The relocation of medical resource should be considered on a global scale.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12938-021-00973-6.

Intestinal Infiltration of Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma Found on Screening Colonoscopy

B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is a malignancy of dysregulated lymphocytes in bone marrow and lymphatics. Extra-nodal involvement has been previously cited to affect areas like the lungs, skin, central nervous system, and kidney. Gastrointestinal (GI) involvement in patients with chronic CLL/SLL is rare. We report a unique case of CLL/SLL found incidentally in a 71-year-old asymptomatic female undergoing a screening colonoscopy. Patients with GI infiltration of CLL/SLL may be asymptomatic like the patient described in this report, or present with symptoms that may resemble inflammatory bowel disease, microscopic colitis, or colon cancer. Therefore, it is important to remain vigilant for the occurrence of other malignancies during the follow-up of CLL/SLL patients.

High expression level of ROR1 and ROR1-signaling associates with venetoclax resistance in chronic lymphocytic leukemia

Although the BH3-mimetic venetoclax is highly cytotoxic for chronic lymphocytic leukemia (CLL) cells, some patients with CLL fail to clear minimal residual disease (MRD). We examined the CLL cells of seven such patients (CLL1-7) and found each had high-level expression of ROR1. By examining the CLL cells from such patients prior to therapy at SC1 and then more than 1 year later (Sample Collection 2 (SC2)), when they had progressive increases in MRD despite continued venetoclax therapy, we found the levels of ROR1 expressed on CLL cells at SC2 were significantly higher than that on CLL cells collected at SC1. At SC2, we also observed upregulation of genes induced by Wnt5a-induced ROR1 signaling, including BCL2L1. Transduction of the CLL-cell-line MEC1 to express ROR1 enhanced expression of target genes induced by ROR1-signaling, increased expression of BCL-XL, and enhanced resistance to venetoclax, even in MEC1 made to express mutant forms of BCL2, which are associated with venetoclax resistance. Treatment of primary CLL cells with Wnt5a also increased their resistance to venetoclax, an effect that could be inhibited by the anti-ROR1 mAb (UC-961, zilovertamab). Collectively, these studies indicate that Wnt5a-induced ROR1-signaling can enhance resistance to venetoclax therapy.

A case of polymorphic dermal angiitis in a B-cell chronic lymphocytic leukemia patient during rituximab therapy

The aim of the study is to describe a case is of clinical interest as the first known occurrence of skin vasculitis during rituximab treatment. The article describes a case of polymorphic dermal angiitis, a combination of hemorrhagic and ulcerative-necrotic forms against the background of rituximab treatment in a 53-year-old woman suffering from chronic lymphocytic leukemia (b-CLL). During four hours after the 5th intravenous administration of rituximab, the appearance of painful rashes on the skin of both shins of a patient was observed. In the following few days, a progression of the pathological skin process was noted. The treatment with prednisolone in the amount of 50 mg/day, amoxicillin and clavulanic acid in the amount of 1000 mg twice per day and Diflucan in a dosage of 50 mg/day for 15 days was prescribed. In a local therapy, wet-drying bandages with antiseptic solutions, combined topic glucocorticosteroid preparations, drugs that improve trophic and tissue regeneration were recommended. After discharge, the patient continued to receive prednisolone in the amount of 50 mg/day for 14 days with a slow decrease in the dosage of the drug until the withdrawal under the supervision of a dermatologist. The described experience of how combined forms of polymorphic dermal angiitis are developing can be considered a result of toxic drug response to rituximab.

Understanding CLL biology through mouse models of human genetics

Rapid advances in large-scale next-generation sequencing studies of human samples have progressively defined the highly heterogeneous genetic landscape of chronic lymphocytic leukemia (CLL). At the same time, the numerous challenges posed by the difficulties in rapid manipulation of primary B cells and the paucity of CLL cell lines have limited the ability to interrogate the function of the discovered putative disease "drivers," defined in human sequencing studies through statistical inference. Mouse models represent a powerful tool to study mechanisms of normal and malignant B-cell biology and for preclinical testing of novel therapeutics. Advances in genetic engineering technologies, including the introduction of conditional knockin/knockout strategies, have opened new opportunities to model genetic lesions in a B-cell-restricted context. These new studies build on the experience of generating the MDR mice, the first example of a genetically faithful CLL model, which recapitulates the most common genomic aberration of human CLL: del(13q). In this review, we describe the application of mouse models to the studies of CLL pathogenesis and disease transformation from an indolent to a high-grade malignancy (ie, Richter syndrome [RS]) and treatment, with a focus on newly developed genetically inspired mouse lines modeling recurrent CLL genetic events. We discuss how these novel mouse models, analyzed using new genomic technologies, allow the dissection of mechanisms of disease evolution and response to therapy with greater depth than previously possible and provide important insight into human CLL and RS pathogenesis and therapeutic vulnerabilities. These models thereby provide valuable platforms for functional genomic analyses and treatment studies.

Interleukin (IL)-9 Supports the Tumor-Promoting Environment of Chronic Lymphocytic Leukemia

Simple Summary

Interleukin 9 (IL-9), a soluble factor secreted by immune cells, has been found in several tumor niches where, depending on the specific tumor type, it either promotes or counteracts tumor development. Recently, IL-9 has been implicated in the development of chronic lymphocytic leukemia, although the underlying molecular mechanism remains unknown. Here, we summarize the current knowledge concerning the roles of IL-9 in disease, with a focus on its implication in the pathogenesis of chronic lymphocytic leukemia.

Abstract

Interleukin (IL)-9 is a soluble factor secreted by immune cells into the microenvironment. Originally identified as a mediator of allergic responses, IL-9 has been detected in recent years in several tumor niches. In solid tumors, it mainly promotes anti-tumor immune responses, while in hematologic malignancies, it sustains the growth and survival of neoplastic cells. IL-9 has been recently implicated in the pathogenesis of chronic lymphocytic leukemia; however, the molecular mechanisms underlying its contribution to this complex neoplasia are still unclear. Here, we summarize the current knowledge of IL-9 in the tumor microenvironment, with a focus on its role in the pathogenesis of chronic lymphocytic leukemia.

Prognostic significance of microRNA 17-92 cluster expression in Egyptian chronic lymphocytic leukemia patients

BACKGROUND

Abnormal expression patterns of microRNAs (miRs) play an important role in the development and progression of malignancy. Identification of the clinical significance and prognostic value of these small molecules in chronic lymphocytic leukemia (CLL); a disease of heterogeneous biological landscape and clinical course, has always been of tremendous translational value.

AIM

To evaluate the prognostic value of microRNA17-92 cluster members in Egyptian CLL patients.

METHODS

The expression levels of miR17-92 cluster members were evaluated by qRT-PCR, including miR17, miR18a, miR19a, miR19b-1, miR20a, and miR92a-1. Other investigations included serum LDH, serum β2 microglobulin (β2M), CD38 and ZAP70 expression by flow cytometry, fluorescence in situ hybridization (FISH) for 17p deletion, and imaging studies (computerized tomography (CT) scans of neck, chest, abdomen, and pelvis or PET-CT scans).

RESULTS

Overexpression of all members of the miRNA17-92 cluster was detected in CLL patients compared to controls (p =  < 0.001 for all miRs while p = 0.01 for miR19b-1). A significant positive correlation between Hb and miR17 and a significant negative correlation between Hb and miR19b-1 were observed (p = 0.041, 0.017 respectively). A statistically significant positive correlation between miR19b-1 expression and each of the WBCs and absolute lymphocytic count (ALC) was detected (p = 0.023, 0.022 respectively). Moreover, a statistically significant relation between miR19b-1 expression and advanced Binet stages was also found (p = 0.05). Regarding miR18a, a statistically significant positive correlation with LDH level was found (p = 0.003). We also found a significant positive correlation between miR92a-1 and β2M level (p = 0.005), as well as a significant relation between miR17 and negative CD38 expression (p = 0.034). However, no significant relationships between any of studied miRNA expression levels and 17p deletion or response to treatment were observed. Patients who expressed miR19b-1 were significantly indicated to start therapy at diagnosis (p = 0.05). The overall survival of CLL patients included in our study was 90.2% after 1 year from the time of diagnosis. Patients with high expression of miR19a had better OS than those with low expression (p = 0.04).

CONCLUSIONS

Overexpression of all members of the miR17-92 cluster was detected in Egyptian CLL patients. MiR18a, miR19b-1, and miR92a-1 also have an adverse prognostic value while miR17 can be considered a good prognostic marker. High expression of miR19a is associated with better OS.

Acalabrutinib: Nursing Considerations for Use in Patients With Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma

BACKGROUND

Acalabrutinib is a next-generation Bruton tyrosine kinase inhibitor (BTKi) that has moved to the forefront of treatment options for patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). Patients with CLL/SLL can experience adverse events and toxicities unique to BTKi therapy.

OBJECTIVES

This article provides an overview of nursing considerations for the treatment of patients with CLL/SLL with acalabrutinib, focusing on safety, toxicity management, and adherence.

METHODS

A review of information identified through structured searches of key publications and websites and data from pivotal clinical trials was performed.

FINDINGS

Increased awareness of the unique disease characteristics of patients with CLL/SLL and of the efficacy and safety profile of acalabrutinib allows nurses to play a vital role in improving patient outcomes. With this knowledge, nurses can support patients through education on potential side effects, drug-drug interactions, and treatment adherence, as well as monitor for clinical symptoms and laboratory findings requiring intervention.

Deepening into Intracellular Signaling Landscape through Integrative Spatial Proteomics and Transcriptomics in a Lymphoma Model

Human Proteome Project (HPP) presents a systematic characterization of the protein landscape under different conditions using several complementary-omic techniques (LC-MS/MS proteomics, affinity proteomics, transcriptomics, etc.). In the present study, using a B-cell lymphoma cell line as a model, comprehensive integration of RNA-Seq transcriptomics, MS/MS, and antibody-based affinity proteomics (combined with size-exclusion chromatography) (SEC-MAP) were performed to uncover correlations that could provide insights into protein dynamics at the intracellular level. Here, 5672 unique proteins were systematically identified by MS/MS analysis and subcellular protein extraction strategies (neXtProt release 2020-21, MS/MS data are available via ProteomeXchange with identifier PXD003939). Moreover, RNA deep sequencing analysis of this lymphoma B-cell line identified 19,518 expressed genes and 5707 protein coding genes (mapped to neXtProt). Among these data sets, 162 relevant proteins (targeted by 206 antibodies) were systematically analyzed by the SEC-MAP approach, providing information about PTMs, isoforms, protein complexes, and subcellular localization. Finally, a bioinformatic pipeline has been designed and developed for orthogonal integration of these high-content proteomics and transcriptomics datasets, which might be useful for comprehensive and global characterization of intracellular protein profiles.

B-cell receptor isotypes differentially associate with cell signaling, kinetics, and outcome in chronic lymphocytic leukemia

In chronic lymphocytic leukemia (CLL), the B cell receptor (BCR) plays a critical role in disease development and progression, as indicated by the therapeutic efficacy of drugs blocking BCR signaling. However, the mechanism(s) underlying BCR responsiveness are not completely defined. Selective engagement of membrane IgM or IgD on CLL cells, each coexpressed by more than 90% of cases, leads to distinct signaling events. Since both IgM and IgD carry the same antigen-binding domains, the divergent actions of the receptors are attributed to differences in immunoglobulin (Ig) structure or the outcome of signal transduction. We showed that IgM, not IgD, level and organization associated with CLL-cell birth rate and the type and consequences of BCR signaling in humans and mice. The latter IgM-driven effects were abrogated when BCR signaling was inhibited. Collectively, these studies demonstrated a critical, selective role for IgM in BCR signaling and B cell fate decisions, possibly opening new avenues for CLL therapy.

A novel class of oxazepine-based anti-cancer agents induces cell death in primary human CLL cells and efficiently reduces tumor growth in Eμ-TCL1 mice through the JNK/STAT4/p66Shc axis

Survival and expansion of malignant B cells in chronic lymphocytic leukemia (CLL) are highly dependent both on intrinsic defects in the apoptotic machinery and on the interactions with cells and soluble factors in the lymphoid microenvironment. The adaptor protein p66Shc is a negative regulator of antigen receptor signaling, chemotaxis and apoptosis whose loss in CLL B cells contributes to their extended survival and poor prognosis. Hence, the identification of compounds that restore p66Shc expression and function in malignant B cells may pave the way to a new therapeutic approach for CLL. Here we show that a novel oxazepine-based compound (OBC-1) restores p66Shc expression in primary human CLL cells by promoting JNK-dependent STAT4 activation without affecting normal B cells. Moreover, we demonstrate that the potent pro-apoptotic activity of OBC-1 in human leukemic cells directly correlates with p66Shc expression levels and is abrogated when p66Shc is genetically deleted. Preclinical testing of OBC-1 and the novel analogue OBC-2 in Eμ-TCL1 tumor-bearing mice resulted in a significantly longer overall survival and a reduction of the tumor burden in the spleen and peritoneum. Interestingly, OBCs promote leukemic cell mobilization from the spleen to the blood, which correlates with upregulation of sphingosine-1-phosphate receptor expression. In summary, our work identifies OBCs as a promising class of compounds that, by boosting p66Shc expression through the activation of the JNK/STAT4 pathway, display dual therapeutic effects for CLL intervention, namely the ability to mobilize cells from secondary lymphoid organs and a potent pro-apoptotic activity against circulating leukemic cells.

Chronic Lymphocytic Leukemia in a Cockatiel (Nymphicus hollandicus)

A 24-year-old, female cockatiel (Nymphicus hollandicus) was diagnosed and treated for chronic lymphocytic leukemia. Diagnosis was based on a persistent lymphocytosis, with counts increasing 10 times from reference intervals with a high percentage of well-differentiated lymphocytes in the bone marrow. Immunohistochemical staining confirmed neoplastic cells of T-cell origin. Specific treatment for the disease was initially withheld but commenced based on an increasing lymphocytosis and decreasing packed cell volume. Therapeutic management of the cockatiel's chronic lymphocytic leukemia was based on human protocols. Treatment with chlorambucil stabilized the disease but did not result in a significant regression of the neoplasm. The bird was euthanatized 15 months after the initial diagnosis and 8 months after treatment commenced. On the postmortem examination, extensive T-cell lymphocytic infiltration was found throughout the internal organs.

Kinobead Profiling Reveals Reprogramming of BCR Signaling in Response to Therapy within Primary CLL Cells

PURPOSE

B-cell receptor (BCR) signaling is critical for the pathogenesis of chronic lymphocytic leukemia (CLL), promoting both malignant cell survival and disease progression. Although vital, understanding of the wider signaling network associated with malignant BCR stimulation is poor. This is relevant with respect to potential changes in response to therapy, particularly involving kinase inhibitors. In the current study, we describe a novel high-resolution approach to investigate BCR signaling in primary CLL cells and track the influence of therapy on signaling response.

EXPERIMENTAL DESIGN

A kinobead/mass spectrometry-based protocol was used to study BCR signaling in primary CLL cells. Longitudinal analysis of samples donated by clinical trial patients was used to investigate the impact of chemoimmunotherapy and ibrutinib on signaling following surface IgM engagement. Complementary Nanostring and immunoblotting analysis was used to verify our findings.

RESULTS

Our protocol isolated a unique, patient-specific signature of over 30 kinases from BCR-stimulated CLL cells. This signature was associated with 13 distinct Kyoto Encyclopedia of Genes and Genomes pathways and showed significant change in cells from treatment-naïve patients compared with those from patients who had previously undergone therapy. This change was validated by longitudinal analysis of clinical trials samples where BCR-induced kinome responses in CLL cells altered between baseline and disease progression in patients failing chemoimmunotherapy and between baseline and treatment in patients taking ibrutinib.

CONCLUSIONS

These data comprise the first comprehensive proteomic investigation of the BCR signaling response within CLL cells and reveal unique evidence that these cells undergo adaptive reprogramming of this signaling in response to therapy.

[Comparison of four prognostic scoring system in patients with early asymptomatic chronic lymphocytic leukemia patients]

Objective: To compare the prognostic value of four prognostic models in predicting time to first treatment (TTFT) in patients with Binet A Chinese chronic lymphocytic leukemia (CLL) . Methods: This retrospective analysis included one hundred and ten patients with Binet A CLL, initially diagnosed in the First Affiliated Hospital of Nanjing Medical University (Pukou CLL center) from June 2009 to January 2020. Risk stratification was conducted according to IPS-E, CLL-IPI, CLL1-PM, and Barcelona-Brno prognostic models. Results: Among 110 patients with Binet A CLL patients, the median age was 58 (25-84) years. The median follow-up time was 35 (4-189) months, and 57 (51.8%) patients met the indication for treatment due to symptomatic disease progression during follow-up. Log-rank analysis of nine variables was conducted involving age, Rai stage, absolute lymphocyte count (ALC) , lymph node size, lymphocyte doubling time (LDT) , β(2)-Microglobulin, IGHV status, TP53, and Del (11q) . Additionally, Rai Ⅰ-Ⅲ, ALC>15×10(9)/L, palpable lymph node size ≥1cm, β(2)-Microglobulin>3.5 mg/L, unmutated IGHV, TP53 mutation or deletion, and 11q deletion were independent risk factors of TTFT. Predictive value of each model was assessed by Harrel C-index and Akaike information criterion (AIC) with CLL1-PM (C-index=0.736, AIC=777) , followed by CLL-IPI (C-index=0.722, AIC=933) , IPS-E (C-index=0.683, AIC=1004) , and Barcelona-Brno prognostic model (C-index=0.663, AIC=986) . Conclusion: All four prognostic models effectively predicted TTFT. IPS-E might be an ideal model to guide clinical surveillance because of its easy accessibility and low expenses in routine clinical practice. Therefore, for patients receiving fluorescence in situ hybridization (FISH) and next-generation sequencing (NGS) examination at diagnosis, CLL-IPI or CLL1-PM could be applied to evaluate their prognosis more comprehensively.

Detailing the epidemiological and clinical characteristics of chronic lymphocytic leukaemia in Portugal-Results from a population-based cancer registry cohort study

BACKGROUND

Chronic lymphocytic leukaemia (CLL) is the most common leukaemia among adults in western countries. Considering the increasing incidence and prevalence of this condition, it is highly relevant to better characterise these patients in Portugal, where data is still scarce.

METHODS

To determine incidence, clinical presentation, survival and second malignancies, a population-based historical cohort study was conducted. Cases of interest were identified through the South Region Cancer Registry database and additional data sources. Patients aged ≥18 years, with a confirmed diagnosis of CLL or small lymphocytic lymphoma between January 1st, 2013 and December 31st, 2014 were included. Patients were followed-up until death or cut-off date (December 31st, 2019).

RESULTS

A total of 496 patients were included and median follow-up time was 5.46 years. Crude incidence rates were 5.03 and 5.22 per 100,000 inhabitants for 2013 and 2014, respectively, and age-adjusted incidence rates were 3.18:100,000 European population for 2013 and 3.35:100,000 European population for 2014. Median age at diagnosis was 71 years and the male/female ratio was 1.40. The majority of patients had leukemic presentation of the disease (86.09%), was diagnosed in Binet stage A (75.58%) and did not present B symptoms (84.01%), anaemia (haemoglobin ≤10g/dL; 90.63%) nor thrombocytopenia (platelet count ≤100 000/μL; 91.73%). Five-year overall survival (OS) rate was 70.53% (95%CI 66.31-74.34) and age, lactate dehydrogenase, Binet stage and a ≥5 Charlson comorbidity index score were independently associated with OS. Standardised-incidence ratios for any second malignancy and cutaneous squamous cell carcinoma were 1.59 (95%CI 1.19-2.08) and 10.15 (95%CI 6.28-15.51), respectively.

CONCLUSION

Incidence, clinical presentation and survival of CLL Portuguese patients are similar to those reported for other western countries. The increased risk of second malignancies raises concerns and needs adequate clinical watchfulness.

Immune checkpoint inhibition therapy for advanced skin cancer in patients with concomitant hematological malignancy: a retrospective multicenter DeCOG study of 84 patients

BACKGROUND

Skin cancers are known for their strong immunogenicity, which may contribute to a high treatment efficacy of immune checkpoint inhibition (ICI). However, a considerable proportion of patients with skin cancer is immuno-compromised by concomitant diseases. Due to their previous exclusion from clinical trials, the ICI treatment efficacy is poorly investigated in these patients. The present study analyzed the ICI treatment outcome in advanced patients with skin cancer with a concomitant hematological malignancy.

METHODS

This retrospective multicenter study included patients who were treated with ICI for locally advanced or metastatic melanoma (MM), cutaneous squamous cell carcinoma (cSCC), or Merkel cell carcinoma (MCC), and had a previous diagnosis of a hematological malignancy irrespective of disease activity or need of therapy at ICI treatment start. Comparator patient cohorts without concomitant hematological malignancy were extracted from the prospective multicenter skin cancer registry ADOREG. Treatment outcome was measured as best overall response, progression-free (PFS), and overall survival (OS).

RESULTS

84 patients (MM, n=52; cSCC, n=15; MCC, n=17) with concomitant hematological malignancy were identified at 20 skin cancer centers. The most frequent concomitant hematological malignancies were non-Hodgkin's lymphoma (n=70), with chronic lymphocytic leukemia (n=32) being the largest entity. While 9 patients received ICI in an adjuvant setting, 75 patients were treated for advanced non-resectable disease (55 anti-PD-1; 8 anti-PD-L1; 5 anti-CTLA-4; 7 combinations). In the latter 75 patients, best objective response (complete response+partial response) was 28.0%, disease stabilization was 25.3%, and 38.6% showed progressive disease (PD). Subdivided by skin cancer entity, best objective response was 31.1% (MM), 26.7% (cSCC), and 18.8% (MCC). Median PFS was 8.4 months (MM), 4.0 months (cSCC), and 5.7 months (MCC). 1-year OS rates were 78.4% (MM), 65.8% (cSCC), and 47.4% (MCC). Comparison with respective ADOREG patient cohorts without hematological malignancy (n=392) revealed no relevant differences in ICI therapy outcome for MM and MCC, but a significantly reduced PFS for cSCC (p=0.002).

CONCLUSIONS

ICI therapy showed efficacy in advanced patients with skin cancer with a concomitant hematological malignancy. Compared with patients without hematological malignancy, the observed ICI therapy outcome was impaired in cSCC, but not in MM or MCC patients.

Towards a Better Characterisation of Leukemic Cells in Chronic Lymphocytic Leukaemia: Cell-Size Heterogeneity Reflects Their Activation Status and Migratory Abilities

Simple Summary

Chronic lymphocytic leukaemia (CLL) is a heterogeneous chronic disease characterised by the clonal expansion of mature CD19⁺CD23⁺CD5⁺ B-cells in blood, bone marrow and lymphoid tissue. Despite the CLL tumour cell population showing considerable heterogeneity in cell size, the functional characteristics of leukemic cells that differ in size have not been explored. The results of our study demonstrate that differences in CLL cell size reflect their activation state, polarisation and migratory capacity, with large CLL cells being more activated, polarised and motile than the small CLL cells present in the CLL cell pool. Our data provide evidence of the importance of cell-size heterogeneity within the CLL cell pool and the dynamics of cell-size changes for disease pathogenesis.

Abstract

Chronic lymphocytic leukaemia (CLL) is a genetically, morphologically and phenotypically heterogeneous chronic disease with clinical variability between patients. Whether the significant heterogeneity of cell size within the CLL population contributes to the heterogeneous features of this disease has not been investigated. The present study aimed to characterise the phenotypic and functional properties of two subpopulations of typical CLL cells that differ in cell size: small (s-CLL) and large (l-CLL) CLL cells delineated by forward scatter cytometry. The s-CLL cells were characterised by the CD5^lowCXCR4^hi phenotype, while the l-CLL cells were characterised by the CD5^hiCXCR4^dim phenotype and indicated a higher expression of CXCR3, CD20, CD38 and HLA-DR. The l-CLL cells displayed higher migration activity towards CXCL12, a tendency towards a higher proliferation rate and an increased capacity to produce IgM in the presence of CpG compared with s-CLL cells. When stimulated with CpG and CXCL12, l-CLL cells were characterised by a higher polarisation phenotype and motility than s-CLL cells. Our study revealed that the differences in CLL cell size reflected their activation status, polarisation and migratory abilities. Our data provide evidence of the importance of cell-size heterogeneity within a CLL pool and the dynamics of cell-size changes for disease pathogenesis, thus deserving further investigation.

LncRNA landscape analysis identified LncRNA LEF-AS1 as an oncogene that upregulates LEF1 and promotes survival in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a malignant disorder of mature B lymphocytes, and the precise pathogenesis is largely unknown at present. This study set out to screen the differential expression profile of long non-coding RNA (lncRNA) by microarray and explore the underlying mechanism, biological function, and clinical significance of lncRNA in CLL cells. Compared to the lncRNA expression profiles of the control group, we picked lncRNA LEF1-AS1 for further exploration. By quantitative real-time polymerase chain reaction (qRT-PCR), we validated that primary CLL cells harbor higher lncRNA LEF1-AS1 levels than normal B cells. In the two cell lines with stable overexpression of LEF1-AS1, expression of LEF1 elevated on RNA and protein level, proliferation rates increased, and apoptosis rates decreased. In primary CLL cells, mRNA expression of LEF1 decreased by qRT-PCR after negatively regulating the expression of LEF1-AS1. RNA Binding Protein Immunoprecipitation and RNA pull-down demonstrated that LncRNA LEF1-AS1 and LEF1 protein could combine especially. This thesis concludes LEF1-AS1 may be an oncogenic lncRNA that regulates the target gene LEF1 by interacting with protein LEF1. However, the prognostic significance of lncRNA LEF1-AS1 in CLL patients is still unclear.

Consistent B Cell Receptor Immunoglobulin Features Between Siblings in Familial Chronic Lymphocytic Leukemia

Key processes in the onset and evolution of chronic lymphocytic leukemia (CLL) are thought to include chronic (antigenic) activation of mature B cells through the B cell receptor (BcR), signals from the microenvironment, and acquisition of genetic alterations. Here we describe three families in which two or more siblings were affected by CLL. We investigated whether there are immunogenetic similarities in the leukemia-specific immunoglobulin heavy (IGH) and light (IGL/IGK) chain gene rearrangements of the siblings in each family. Furthermore, we performed array analysis to study if similarities in CLL-associated chromosomal aberrations are present within each family and screened for somatic mutations using paired tumor/normal whole-genome sequencing (WGS). In two families a consistent IGHV gene mutational status (one IGHV-unmutated, one IGHV-mutated) was observed. Intriguingly, the third family with four affected siblings was characterized by usage of the lambda IGLV3-21 gene, with the hallmark R110 mutation of the recently described clinically aggressive IGLV3-21^R110 subset. In this family, the CLL-specific rearrangements in two siblings could be assigned to either stereotyped subset #2 or the immunogenetically related subset #169, both of which belong to the broader IGLV3-21^R110 subgroup. Consistent patterns of cytogenetic aberrations were encountered in all three families. Furthermore, the CLL clones carried somatic mutations previously associated with IGHV mutational status, cytogenetic aberrations and stereotyped subsets, respectively. From these findings, we conclude that similarities in immunogenetic characteristics in familial CLL, in combination with genetic aberrations acquired, point towards shared underlying mechanisms behind CLL development within each family.

Targeted inhibition of eIF4A suppresses B-cell receptor-induced translation and expression of MYC and MCL1 in chronic lymphocytic leukemia cells

Signaling via the B-cell receptor (BCR) is a key driver and therapeutic target in chronic lymphocytic leukemia (CLL). BCR stimulation of CLL cells induces expression of eIF4A, an initiation factor important for translation of multiple oncoproteins, and reduces expression of PDCD4, a natural inhibitor of eIF4A, suggesting that eIF4A may be a critical nexus controlling protein expression downstream of the BCR in these cells. We, therefore, investigated the effect of eIF4A inhibitors (eIF4Ai) on BCR-induced responses. We demonstrated that eIF4Ai (silvestrol and rocaglamide A) reduced anti-IgM-induced global mRNA translation in CLL cells and also inhibited accumulation of MYC and MCL1, key drivers of proliferation and survival, respectively, without effects on upstream signaling responses (ERK1/2 and AKT phosphorylation). Analysis of normal naïve and non-switched memory B cells, likely counterparts of the two main subsets of CLL, demonstrated that basal RNA translation was higher in memory B cells, but was similarly increased and susceptible to eIF4Ai-mediated inhibition in both. We probed the fate of MYC mRNA in eIF4Ai-treated CLL cells and found that eIF4Ai caused a profound accumulation of MYC mRNA in anti-IgM treated cells. This was mediated by MYC mRNA stabilization and was not observed for MCL1 mRNA. Following drug wash-out, MYC mRNA levels declined but without substantial MYC protein accumulation, indicating that stabilized MYC mRNA remained blocked from translation. In conclusion, BCR-induced regulation of eIF4A may be a critical signal-dependent nexus for therapeutic attack in CLL and other B-cell malignancies, especially those dependent on MYC and/or MCL1.

Performance of anti-CD19 chimeric antigen receptor T cells in genetically defined classes of chronic lymphocytic leukemia

Background

While achieving prolonged remissions in other B cell-derived malignancies, chimeric antigen receptor (CAR) T cells still underperform when injected into patients with chronic lymphocytic leukemia (CLL). We studied the influence of genetics on CLL response to anti-CD19 CAR T-cell therapy.

Methods

First, we studied 32 primary CLL samples composed of 26 immunoglobulin heavy-chain gene variable (IGHV)-unmutated (9 ATM-mutated, 8 TP53-mutated, and 9 without mutations in ATM, TP53, NOTCH1 or SF3B1) and 6 IGHV-mutated samples without mutations in the above-mentioned genes. Then, we mimicked the leukemic microenvironment in the primary cells by ‘2S stimulation’ through interleukin-2 and nuclear factor kappa B. Finally, CRISPR/Cas9-generated ATM-knockout and TP53-knockout clones (four and seven, respectively) from CLL-derived cell lines MEC1 and HG3 were used. All these samples were exposed to CAR T cells. In vivo survival study in NSG mice using HG3 wild-type (WT), ATM-knockout or TP53-knockout cells was also performed.

Results

Primary unstimulated CLL cells were specifically eliminated after >24 hours of coculture with CAR T cells. ‘2S’ stimulated cells showed increased survival when exposed to CAR T cells compared with unstimulated ones, confirming the positive effect of this stimulation on CLL cells’ in vitro fitness. After 96 hours of coculture, there was no difference in survival among the genetic classes. Finally, CAR T cells were specifically activated in vitro in the presence of target knockout cell lines as shown by the production of interferon-γ when compared with control (CTRL) T cells (p=0.0020), but there was no difference in knockout cells’ survival. In vivo, CAR T cells prolonged the survival of mice injected with WT, TP53-knockout and ATM-knockout HG3 tumor cells as compared with CTRL T cells (p=0.0485, 0.0204 and <0.0001, respectively). When compared with ATM-knockout, TP53-knockout disease was associated with an earlier time of onset (p<0.0001), higher tumor burden (p=0.0002) and inefficient T-cell engraftment (p=0.0012).

Conclusions

While in vitro no differences in survival of CLL cells of various genetic backgrounds were observed, CAR T cells showed a different effectiveness at eradicating tumor cells in vivo depending on the driver mutation. Early disease onset, high-tumor burden and inefficient T-cell engraftment, associated with TP53-knockout tumors in our experimental setting, ultimately led to inferior performance of CAR T cells.

Sudden death due to leukostasis in a subject with undiagnosed chronic lymphocytic leukemia

Sudden death due to leukostasis and lymphocyte thrombi in patients with chronic hematologic malignancies is rare. Leukostasis is characterized by highly elevated leukemic cell count and decreased tissue perfusion symptoms, leading to severe complications and even death. Chronic lymphocytic leukemia (CLL) is a chronic lymphoproliferative disorder that shows a highly heterogeneous clinical course, ranging from indolent form to very aggressive disease. Due to its low metabolic and mitotic rate, there is a lower incidence of clinically significant leukostasis in patients with CLL. Two main theories have been proposed in the development of leukostasis: (1) increased blood viscosity due to large leukemic cell populations; (2) high metabolic activity and cytokine production by leukemic cells. Both mechanisms lead to local hypoxic damage.We present a case of a 70-year-old man who died suddenly in the absence of symptoms. Autopsy and histology examinations revealed findings consistent with CLL and diffuse leukostasis involving the major organs' vessels.In the presence of gross and/or microscopic findings suggesting a potential hematologic malignancy, undiagnosed or relapsing hematologic malignancies should be considered in the differential diagnosis of sudden deaths.

Lymphocyte Doubling Time As A Key Prognostic Factor To Predict Time To First Treatment In Early-Stage Chronic Lymphocytic Leukemia

The prognostic role of lymphocyte doubling time (LDT) in chronic lymphocytic leukemia (CLL) was recognized more than three decades ago when the neoplastic clone’s biology was almost unknown. LDT was defined as the time needed for the peripheral blood lymphocyte count to double the of the initial observed value. Herein, the LDT prognostic value for time to first treatment (TTFT) was explored in our prospective O-CLL cohort and validated in in two additional CLL cohorts. Specifically, newly diagnosed Binet stage A CLL patients from 40 Italian Institutions, representative of the whole country, were prospectively enrolled into the O-CLL1-GISL protocol (clinicaltrial.gov identifier: NCT00917540). Two independent cohorts of newly diagnosed CLL patients recruited respectively at the Division of Hematology in Novara, Italy, and at the Hospital Clinic in Barcelona, Spain, were utilized as validation cohorts. In the training cohort, TTFT of patients with LDT >12 months was significantly longer related to those with a shorter LDT. At Cox multivariate regression model, LDT ≤ 12 months maintained a significant independent relationship with shorter TTFT along with IGHV unmutated (IGHVunmut) status, 11q and 17p deletions, elevated β2M, Rai stage I-II, and NOTCH1 mutations. Based on these statistics, two regression models were constructed including the same prognostic factors with or without the LDT. The model with the LTD provided a significantly better data fitting (χ² = 8.25, P=0.0041). The risk prediction developed including LDT had better prognostic accuracy than those without LDT. Moreover, the Harrell’C index for the scores including LDT were higher than those without LDT, although the accepted 0.70 threshold exceeded in both cases. These findings were also confirmed when the same analysis was carried out according to TTFT’s explained variation. When data were further analyzed based on the combination between LDT and IGHV mutational status in the training and validation cohorts, IGHVunmut and LDT>12months group showed a predominant prognostic role over IGHVmut LTD ≤ 12 months (P=0.006) in the O-CLL validation cohort. However, this predominance was of borden-line significance (P=0.06) in the Barcelona group, while the significant prognostic impact was definitely lost in the Novara group. Overall, in this study, we demonstrated that LDT could be re-utilized together with the more sophisticated prognostic factors to manage the follow-up plans for Binet stage A CLL patients.

Real-world treatment sequencing and healthcare costs among CLL/SLL patients treated with venetoclax

OBJECTIVE

This study aimed to describe treatment sequencing and healthcare costs among chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) patients treated with venetoclax in a US managed care population.

METHODS

CLL/SLL patients initiating venetoclax between 04/11/2016 and 06/30/2019 were selected from Optum's de-identified Clinformatics Data Mart Database. Costs per-patient-per-month were described during the first 60 days of venetoclax-based treatment (initiation phase) and subsequent post-initiation phase. Based on venetoclax prescribing information, clinical event-related costs were identified through claims for tumor lysis syndrome (TLS) diagnosis, monitoring, prophylaxis, immunoglobulin treatment, neutropenia, thrombocytopenia, infection, renal impairment, hypertension, or cardiac arrhythmia. Statistical testing was not conducted due to small sample size.

RESULTS

Twenty-five, 30, and 66 patients initiated venetoclax as their first observed regimen (1L), second observed regimen (2L), and third or later observed regimen (3L+), respectively. Most 2L (56.7%) and 3L+ (74.2%) venetoclax recipients previously received ibrutinib. Mean monthly all-cause costs during the initiation phase were $26,429 (1L cohort), $19,580 (2L cohort), and $23,918 (3L + cohort). Among the 2L cohort, mean monthly all-cause [clinical event-related] (including TLS) costs during initiation and post-initiation phases of venetoclax treatment were $15,506 [$6368] (initiation phase) and $14,318 [$5273] (post-initiation phase; median duration: 3.7 months) for patients receiving 1L ibrutinib, and $24,908 [$12,198] (initiation phase) and $16,905 [$7066] (post-initiation phase; median duration: 3.0 months) for patients not receiving 1L ibrutinib.

CONCLUSIONS

In this descriptive study, highest mean costs were observed during venetoclax initiation phase. Venetoclax patients previously receiving ibrutinib had lower mean total all-cause and clinical event-related (including TLS) costs during their venetoclax line of therapy than those previously receiving non-ibrutinib therapy.

Acalabrutinib in management of chronic lymphocytic leukemia: An Indian perspective

The treatment landscape of chronic lymphocytic leukemia (CLL) has witnessed immense changes in the past decade. Several newer target therapies and their combinations with anti-CD 20 therapies have got approval for management of CLL in the treatment-naïve and relapsed/refractory setting. Also, the availability of newer diagnostic techniques has helped differentiate the disease into high- and low-risk CLL which acts not just as a prognostic marker but also helps decide the best drug management that can be administered to the patients. Targeted therapy has largely overtaken chemoimmunotherapy in the management of CLL, except for a small subset of the population (young and fit with IGHV mutation). However, with targeted therapy, there is also an issue of previously uncommon treatment-emergent adverse events, the duration of therapy, and financial toxicity. The aim of this review article is to gather results from all landmark CLL trials and discuss the feasibility of incorporating Acalabrutinib in the CLL landscape from an Indian perspective.

AID overexpression leads to aggressive murine CLL and nonimmunoglobulin mutations that mirror human neoplasms

Most cancers become more dangerous by the outgrowth of malignant subclones with additional DNA mutations that favor proliferation or survival. Using chronic lymphocytic leukemia (CLL), a disease that exemplifies this process and is a model for neoplasms in general, we created transgenic mice overexpressing the enzyme activation-induced deaminase (AID), which has a normal function of inducing DNA mutations in B lymphocytes. AID not only allows normal B lymphocytes to develop more effective immunoglobulin-mediated immunity, but is also able to mutate nonimmunoglobulin genes, predisposing to cancer. In CLL, AID expression correlates with poor prognosis, suggesting a role for this enzyme in disease progression. Nevertheless, direct experimental evidence identifying the specific genes that are mutated by AID and indicating that those genes are associated with disease progression is not available. To address this point, we overexpressed Aicda in a murine model of CLL (Eμ-TCL1). Analyses of TCL1/AID mice demonstrate a role for AID in disease kinetics, CLL cell proliferation, and the development of cancer-related target mutations with canonical AID signatures in nonimmunoglobulin genes. Notably, our mouse models can accumulate mutations in the same genes that are mutated in human cancers. Moreover, some of these mutations occur at homologous positions, leading to identical or chemically similar amino acid substitutions as in human CLL and lymphoma. Together, these findings support a direct link between aberrant AID activity and CLL driver mutations that are then selected for their oncogenic effects, whereby AID promotes aggressiveness in CLL and other B-cell neoplasms.

Mantle cell lymphoma, malt lymphoma, small lymphocytic lymphoma, and follicular lymphoma of the oral cavity: An update

BACKGROUND

Although uncommon, mature small B-cell lymphomas may arise in the oral/maxillofacial area and oral pathologists must be aware of the key characteristics of these neoplasms to perform an accurate diagnosis. In this manuscript, we attempted to integrate the currently available data on the clinicopathological features of follicular lymphoma (FL), mantle cell lymphoma (MCL), extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT-L), and chronic lymphocytic leukemia/ small lymphocytic lymphoma (CLL/SLL) affecting these anatomical regions.

METHODS

An updated descriptive literature review was carried out and a detailed electronic search was done in multiple databases to gather all cases affecting the oral/maxillofacial region and palatine tonsils.

RESULTS

We observed that MALT-L was the most frequently reported subtype, followed by FL, MCL, and CLL/SLL. The palate was affected in a high proportion of cases and the most usual clinical presentation was an asymptomatic swelling. MALT-L and CLL/SLL neoplastic cells were strongly associated with small salivary glands. FL showed no gender preference, while MCL and CLL/SLL were more prevalent in males and MALT-L in females. Overall, cases were more common in elderly individuals. Patients' treatment and outcome varied, with MCL being the most aggressive neoplasm with a dismal prognosis in comparison to FL and MALT-L.

CONCLUSION

Despite the poor documentation in many of the cases available, especially regarding the microscopic and molecular features of tumors, this review demonstrated that the oral mature small B-cell lymphomas investigated share similar clinical presentation, but carry different prognostic significance, demanding an accurate diagnosis.

Leukaemia: a model metastatic disease

In contrast to solid cancers, which often require genetic modifications and complex cellular reprogramming for effective metastatic dissemination, leukaemic cells uniquely possess the innate ability for migration and invasion. Dedifferentiated, malignant leukocytes retain the benign leukocytes' capacity for cell motility and survival in the circulation, while acquiring the potential for rapid and uncontrolled cell division. For these reasons, leukaemias, although not traditionally considered as metastatic diseases, are in fact models of highly efficient metastatic spread. Accordingly, they are often aggressive and challenging diseases to treat. In this Perspective, we discuss the key molecular processes that facilitate metastasis in a variety of leukaemic subtypes, the clinical significance of leukaemic invasion into specific tissues and the current pipeline of treatments targeting leukaemia metastasis.

Optimal Management of Chronic Lymphocytic Leukemia and Economic Constraints

ABSTRACT

In this article, we carry out an overview on the management options available for chronic lymphocytic leukemia (CLL) patients and discuss possible treatment decisions, taking into account the issue of sustainability and availability. Targeted agents have shown to be superior compared with chemoimmunotherapy (CIT) in terms of progression-free survival in high-risk CLL. In the majority of studies, however, continuous treatment was compared with fixed-duration CIT and no overall survival or progression-free survival-2 (time from randomization to second progression or death) advantage could be documented. Meanwhile, a substantial financial burden on both patients and payers has raised issues about affordability and adherence to treatment. Therefore, value-based pricing of new drugs has been used to set up price negotiation policies in several countries, and fixed-duration therapy has shown to be less costly than continuous treatment. Thus, CIT continues to have a role in the treatment of CLL patients with a favorable genetic profile, that is, with a mutated IGHV gene profile and a wild-type TP53. Targeted treatment represents the preferred choice in patients with an unmutated IGHV gene configuration and/or a TP53 disruption, provided that adherence to treatment is guaranteed and bearing in mind that should costly drugs not be available for frontline treatment, new agents can be very effective as first salvage treatment.

Multivariate transcriptome analysis identifies networks and key drivers of chronic lymphocytic leukemia relapse risk and patient survival

BACKGROUND

Chronic lymphocytic leukemia (CLL) is an indolent heme malignancy characterized by the accumulation of CD5+ CD19+ B cells and episodes of relapse. The biological signaling that influence episodes of relapse in CLL are not fully described. Here, we identify gene networks associated with CLL relapse and survival risk.

METHODS

Networks were investigated by using a novel weighted gene network co-expression analysis method and examining overrepresentation of upstream regulators and signaling pathways within co-expressed transcriptome modules across clinically annotated transcriptomes from CLL patients (N = 203). Gene Ontology analysis was used to identify biological functions overrepresented in each module. Differential Expression of modules and individual genes was assessed using an ANOVA (Binet Stage A and B relapsed patients) or T-test (SF3B1 mutations). The clinical relevance of biomarker candidates was evaluated using log-rank Kaplan Meier (survival and relapse interval) and ROC tests.

RESULTS

Eight distinct modules (M2, M3, M4, M7, M9, M10, M11, M13) were significantly correlated with relapse and differentially expressed between relapsed and non-relapsed Binet Stage A CLL patients. The biological functions of modules positively correlated with relapse were carbohydrate and mRNA metabolism, whereas negatively correlated modules to relapse were protein translation associated. Additionally, M1, M3, M7, and M13 modules negatively correlated with overall survival. CLL biomarkers BTK, BCL2, and TP53 were co-expressed, while unmutated IGHV biomarker ZAP70 and cell survival-associated NOTCH1 were co-expressed in modules positively correlated with relapse and negatively correlated with survival days.

CONCLUSIONS

This study provides novel insights into CLL relapse biology and pathways associated with known and novel biomarkers for relapse and overall survival. The modules associated with relapse and overall survival represented both known and novel pathways associated with CLL pathogenesis and can be a resource for the CLL research community. The hub genes of these modules, e.g., ARHGAP27P2, C1S, CASC2, CLEC3B, CRY1, CXCR5, FUT5, MID1IP1, and URAHP, can be studied further as new therapeutic targets or clinical markers to predict CLL patient outcomes.

Identification of Clinically Relevant Subgroups of Chronic Lymphocytic Leukemia Through Discovery of Abnormal Molecular Pathways

Chronic lymphocytic leukemia (CLL) is the most common form of adult leukemia in the Western world with a highly variable clinical course. Its striking genetic heterogeneity is not yet fully understood. Although the CLL genetic landscape has been well-described, patient stratification based on mutation profiles remains elusive mainly due to the heterogeneity of data. Here we attempted to decrease the heterogeneity of somatic mutation data by mapping mutated genes in the respective biological processes. From the sequencing data gathered by the International Cancer Genome Consortium for 506 CLL patients, we generated pathway mutation scores, applied ensemble clustering on them, and extracted abnormal molecular pathways with a machine learning approach. We identified four clusters differing in pathway mutational profiles and time to first treatment. Interestingly, common CLL drivers such as ATM or TP53 were associated with particular subtypes, while others like NOTCH1 or SF3B1 were not. This study provides an important step in understanding mutational patterns in CLL.

NK Cells in Chronic Lymphocytic Leukemia and Their Therapeutic Implications

Key features of chronic lymphocytic leukemia (CLL) are defects in the immune system and the ability of leukemic cells to evade immune defenses and induce immunosuppression, resulting in increased susceptibility to infections and disease progression. Several immune effectors are impaired in CLL, including T and natural killer (NK) cells. The role of T cells in defense against CLL and in CLL progression and immunotherapy has been extensively studied. Less is known about the role of NK cells in this leukemia, and data on NK cell alterations in CLL are contrasting. Besides studies showing that NK cells have intrinsic defects in CLL, there is a large body of evidence indicating that NK cell dysfunctions in CLL mainly depend on the escape mechanisms employed by leukemic cells. In keeping, it has been shown that NK cell functions, including antibody-dependent cellular cytotoxicity (ADCC), can be retained and/or restored after adequate stimulation. Therefore, due to their preserved ADCC function and the reversibility of CLL-related dysfunctions, NK cells are an attractive source for novel immunotherapeutic strategies in this disease, including chimeric antigen receptor (CAR) therapy. Recently, satisfying clinical responses have been obtained in CLL patients using cord blood-derived CAR-NK cells, opening new possibilities for further exploring NK cells in the immunotherapy of CLL. However, notwithstanding the promising results of this clinical trial, more evidence is needed to fully understand whether and in which CLL cases NK cell-based immunotherapy may represent a valid, alternative/additional therapeutic option for this leukemia. In this review, we provide an overview of the current knowledge about phenotypic and functional alterations of NK cells in CLL and the mechanisms by which CLL cells circumvent NK cell-mediated immunosurveillance. Additionally, we discuss the potential relevance of using NK cells in CLL immunotherapy.

Vascular Impact of Cancer Therapies: The Case of BTK (Bruton Tyrosine Kinase) Inhibitors

Novel targeted cancer therapies have revolutionized oncology therapies, but these treatments can have cardiovascular complications, which include heterogeneous cardiac, metabolic, and vascular sequelae. Vascular side effects have emerged as important considerations in both cancer patients undergoing active treatment and cancer survivors. Here, we provide an overview of vascular effects of cancer therapies, focusing on small-molecule kinase inhibitors and specifically inhibitors of BTK (Bruton tyrosine kinase), which have revolutionized treatment and prognosis for B-cell malignancies. Cardiovascular side effects of BTK inhibitors include atrial fibrillation, increased risk of bleeding, and hypertension, with the former 2 especially providing a treatment challenge for the clinician. Cardiovascular complications of small-molecule kinase inhibitors can occur through either on-target (targeting intended target kinase) or off-target kinase inhibition. We will review these concepts and focus on the case of BTK inhibitors, highlight the emerging data suggesting an off-target effect that may provide insights into development of arrhythmias, specifically atrial fibrillation. We believe that cardiac and vascular sequelae of novel targeted cancer therapies can provide insights into human cardiovascular biology.

Acute coronary syndrome secondary to cardiac infiltration and coronary occlusion of chronic lymphocytic leukemia - A case report

A 72-year-old male with a history of chronic lymphocytic leukemia (CLL) was admitted to hospital with a productive cough and an episode of diarrhea and vomiting. He was initially treated for pneumonitis and sepsis. On the 12th day of his admission, he reported chest pain. Changes on his electrocardiogram were suggestive of myocardial ischemia and an elevated troponin rise was detected from his blood tests. A diagnosis of acute coronary syndrome was made but due to his frailty, he was medically managed. His echocardiogram revealed an external echogenic mass which invaded the anterolateral left ventricular wall. Further imaging with cardiac magnetic resonance imaging (MRI) and computed tomography (CT) thorax demonstrated external encasement of left circumflex coronary artery with mediastinal mass, leading into downstream myocardial ischemia and subsequent necrosis. He was considered suitable for aggressive radiotherapy/chemotherapy but passed away 7 days later. This case highlights the unusual case where an acute myocardial infarction can be attributed to direct infiltration and external compression of coronary artery by mediastinal tumor and the value of multi-modality imaging (echocardiogram, CT, and MRI) in identifying the cause of myocardial ischemia in patients with CLL in the end stages of the disease. .

CARD11 is a novel target of miR-181b that is upregulated in chronic lymphocytic leukemia

Aim: To investigate the targets of miR-181b in patients with chronic lymphocytic leukemia (CLL). Materials & methods: The bioinformatic softwares were used to indicate the key target genes associated with miR-181b, and the results were verified in CLL patient samples and 293T cells. Results: CARD11 is a potential target gene of miR-181b, an inverse relationship was revealed between the expression of CARD11 and miR-181b in 104 CLL patients, and it was confirmed in vitro with luciferase assays and western blotting. Kaplan-Meier analysis showed that CLL patients with high CARD11 expression demonstrated poor survival. Conclusion: CARD11 is a novel target of miR-181b that is upregulated, which could be a poor prognostic indicator for CLL patients.

Post-Transformation IGHV-IGHD-IGHJ Mutations in Chronic Lymphocytic Leukemia B Cells: Implications for Mutational Mechanisms and Impact on Clinical Course

Analyses of IGHV gene mutations in chronic lymphocytic leukemia (CLL) have had a major impact on the prognostication and treatment of this disease. A hallmark of IGHV-mutation status is that it very rarely changes clonally over time. Nevertheless, targeted and deep DNA sequencing of IGHV-IGHD-IGHJ regions has revealed intraclonal heterogeneity. We used a DNA sequencing approach that achieves considerable depth and minimizes artefacts and amplification bias to identify IGHV-IGHD-IGHJ subclones in patients with prolonged temporal follow-up. Our findings extend previous studies, revealing intraclonal IGHV-IGHD-IGHJ diversification in almost all CLL clones. Also, they indicate that some subclones with additional IGHV-IGHD-IGHJ mutations can become a large fraction of the leukemic burden, reaching numerical criteria for monoclonal B-cell lymphocytosis. Notably, the occurrence and complexity of post-transformation IGHV-IGHD-IGHJ heterogeneity and the expansion of diversified subclones are similar among U-CLL and M-CLL patients. The molecular characteristics of the mutations present in the parental, clinically dominant CLL clone (CDC) differed from those developing post-transformation (post-CDC). Post-CDC mutations exhibit significantly lower fractions of mutations bearing signatures of activation induced deaminase (AID) and of error-prone repair by Polη, and most of the mutations were not ascribable to those enzymes. Additionally, post-CDC mutations displayed a lower percentage of nucleotide transitions compared with transversions that was also not like the action of AID. Finally, the post-CDC mutations led to significantly lower ratios of replacement to silent mutations in VH CDRs and higher ratios in VH FRs, distributions different from mutations found in normal B-cell subsets undergoing an AID-mediated process. Based on these findings, we propose that post-transformation mutations in CLL cells either reflect a dysfunctional standard somatic mutational process or point to the action of another mutational process not previously associated with IG V gene loci. If the former option is the case, post-CDC mutations could lead to a lesser dependence on antigen dependent BCR signaling and potentially a greater influence of off-target, non-IG genomic mutations. Alternatively, the latter activity could add a new stimulatory survival/growth advantage mediated by the BCR through structurally altered FRs, such as that occurring by superantigen binding and stimulation.

TOSO interacts with SYK and enhances BCR pathway activation in chronic lymphocytic leukemia

Background

TOSO, also named Fas inhibitory molecule 3 (FAIM3), has recently been identified as an immunoglobulin M (IgM) Fc receptor (FcμR). Previous studies have shown that TOSO is specifically over-expressed in chronic lymphocytic leukemia (CLL). However, the functions of TOSO in CLL remain unknown. The B-cell receptor (BCR) signaling pathway has been reported to be constitutively activated in CLL. Here, we aimed to investigate the functions of TOSO in the BCR signaling pathway and the pathogenesis of CLL.

Methods

We over-expressed TOSO in B-cell lymphoma cell lines (Granta-519 and Z138) by lentiviral transduction and knocked down TOSO by siRNA in primary CLL cells. The over-expression and knockdown of TOSO were confirmed at the RNA level by polymerase chain reaction and protein level by Western blotting. Co-immunoprecipitation with TOSO antibody followed by liquid chromatography coupled with tandem mass spectrometry (IP/LCMS) was used to identify TOSO interacting proteins. Western blotting was performed to detect the activation status of BCR signaling pathways as well as B-cell lymphoma 2 (BCL-2). Flow cytometry was used to examine the apoptosis of TOSO-over-expressing B lymphoma cell lines and TOSO-down-regulated CLL cells via the staining of Annexin V and 7-AAD. One-way analyses of variance were used for intergroup comparisons, while independent samples t tests were used for two-sample comparisons.

Results

From IP/LCMS, we identified spleen tyrosine kinase (SYK) as a crucial candidate of TOSO-interacting protein and confirmed it by co-immunoprecipitation. After stimulation with anti-IgM, TOSO over-expression increased the phosphorylation of SYK, and subsequently activated the BCR signaling pathway, which could be reversed by a SYK inhibitor. TOSO knockdown in primary CLL cells resulted in reduced SYK phosphorylation as well as attenuated BCR signaling pathway. The apoptosis rates of the Granta-519 and Z138 cells expressing TOSO were (8.46 ± 2.90)% and (4.20 ± 1.21)%, respectively, significantly lower than the rates of the control groups, which were (25.20 ± 4.60)% and (19.72 ± 1.10)%, respectively (P < 0.05 for both). The apoptosis rate was reduced after knocking down TOSO in the primary CLL cells. In addition, we also found that TOSO down-regulation in primary cells from CLL patients led to decreased expression of BCL-2 as well as lower apoptosis, and vice versa in the cell line.

Conclusions

TOSO might be involved in the pathogenesis of CLL by interacting with SYK, enhancing the BCR signaling pathway, and inducing apoptosis resistance.

Breast and Lung Effusion Survival Score Models: Improving Survival Prediction in Patients With Malignant Pleural Effusion and Metastasis

BACKGROUND

Evidence-based guidelines recommend management strategies for malignant pleural effusions (MPEs) based on life expectancy. Existent risk-prediction rules do not provide precise individualized survival estimates.

RESEARCH QUESTION

Can a newly developed continuous risk-prediction survival model for patients with MPE and known metastatic disease provide precise survival estimates?

STUDY DESIGN AND METHODS

Single-center retrospective cohort study of patients with proven malignancy, pleural effusion, and known metastatic disease undergoing thoracentesis from 2014 through 2017. The outcome was time from thoracentesis to death. Risk factors were identified using Cox proportional hazards models. Effect-measure modification (EMM) was tested using the Mantel-Cox test and was addressed by using disease-specific models (DSMs) or interaction terms. Three DSMs and a combined model using interactions were generated. Discrimination was evaluated using Harrell's C-statistic. Calibration was assessed by observed-minus-predicted probability graphs at specific time points. Models were validated using patients treated from 2010 through 2013. Using LENT (pleural fluid lactate dehydrogenase, Eastern Cooperative Oncology Group performance score, neutrophil-to-lymphocyte ratio and tumor type) variables, we generated both discrete (LENT-D) and continuous (LENT-C) models, assessing discrete vs continuous predictors' performances.

RESULTS

The development and validation cohort included 562 and 727 patients, respectively. The Mantel-Cox test demonstrated interactions between cancer type and neutrophil to lymphocyte ratio (P < .0001), pleural fluid lactate dehydrogenase (P = .029), and bilateral effusion (P = .002). DSMs for lung, breast, and hematologic malignancies showed C-statistics of 0.72, 0.72, and 0.62, respectively; the combined model's C-statistics was 0.67. LENT-D (C-statistic, 0.60) and LENT-C (C-statistic, 0.65) models underperformed.

INTERPRETATION

EMM is present between cancer type and other predictors; thus, DSMs outperformed the models that failed to account for this. Discrete risk-prediction models lacked enough precision to be useful for individual-level predictions.

AID in Chronic Lymphocytic Leukemia: Induction and Action During Disease Progression

The enzyme activation-induced cytidine deaminase (AID) initiates somatic hypermutation (SHM) and class switch recombination (CSR) of immunoglobulin (Ig) genes, critical actions for an effective adaptive immune response. However, in addition to the benefits generated by its physiological roles, AID is an etiological factor for the development of human and murine leukemias and lymphomas. This review highlights the pathological role of AID and the consequences of its actions on the development, progression, and therapeutic refractoriness of chronic lymphocytic leukemia (CLL) as a model disease for mature lymphoid malignancies. First, we summarize pertinent aspects of the expression and function of AID in normal B lymphocytes. Then, we assess putative causes for AID expression in leukemic cells emphasizing the role of an activated microenvironment. Thirdly, we discuss the role of AID in lymphomagenesis, in light of recent data obtained by NGS analyses on the genomic landscape of leukemia and lymphomas, concentrating on the frequency of AID signatures in these cancers and correlating previously described tumor-gene drivers with the presence of AID off-target mutations. Finally, we discuss how these changes could affect tumor suppressor and proto-oncogene targets and how they could be associated with disease progression. Collectively, we hope that these sections will help to better understand the complex paradox between the physiological role of AID in adaptive immunity and its potential causative activity in B-cell malignancies.

The Evolving Landscape of Chronic Lymphocytic Leukemia on Diagnosis, Prognosis and Treatment

The knowledge of chronic lymphocytic leukemia (CLL) has progressively deepened during the last forty years. Research activities and clinical studies have been remarkably fruitful in novel findings elucidating multiple aspects of the pathogenesis of the disease, improving CLL diagnosis, prognosis and treatment. Whereas the diagnostic criteria for CLL have not substantially changed over time, prognostication has experienced an expansion with the identification of new biological and genetic biomarkers. Thanks to next-generation sequencing (NGS), an unprecedented number of gene mutations were identified with potential prognostic and predictive value in the 2010s, although significant work on their validation is still required before they can be used in a routine clinical setting. In terms of treatment, there has been an impressive explosion of new approaches based on targeted therapies for CLL patients during the last decade. In this current chemotherapy-free era, BCR and BCL2 inhibitors have changed the management of CLL patients and clearly improved their prognosis and quality of life. In this review, we provide an overview of these novel advances, as well as point out questions that should be further addressed to continue improving the outcomes of patients.

miR-29 modulates CD40 signaling in chronic lymphocytic leukemia by targeting TRAF4: an axis affected by BCR inhibitors

B-cell receptor (BCR) signaling and T-cell interactions play a pivotal role in chronic lymphocytic leukemia (CLL) pathogenesis and disease aggressiveness. CLL cells can use microRNAs (miRNAs) and their targets to modulate microenvironmental interactions in the lymph node niches. To identify miRNA expression changes in the CLL microenvironment, we performed complex profiling of short noncoding RNAs in this context by comparing CXCR4/CD5 intraclonal cell subpopulations (CXCR4dimCD5bright vs CXCR4brightCD5dim cells). This identified dozens of differentially expressed miRNAs, including several that have previously been shown to modulate BCR signaling (miR-155, miR-150, and miR-22) but also other candidates for a role in microenvironmental interactions. Notably, all 3 miR-29 family members (miR-29a, miR-29b, miR-29c) were consistently down-modulated in the immune niches, and lower miR-29(a/b/c) levels associated with an increased relative responsiveness of CLL cells to BCR ligation and significantly shorter overall survival of CLL patients. We identified tumor necrosis factor receptor-associated factor 4 (TRAF4) as a novel direct target of miR-29s and revealed that higher TRAF4 levels increase CLL responsiveness to CD40 activation and downstream nuclear factor-κB (NF-κB) signaling. In CLL, BCR represses miR-29 expression via MYC, allowing for concurrent TRAF4 upregulation and stronger CD40-NF-κB signaling. This regulatory loop is disrupted by BCR inhibitors (bruton tyrosine kinase [BTK] inhibitor ibrutinib or phosphatidylinositol 3-kinase [PI3K] inhibitor idelalisib). In summary, we showed for the first time that a miRNA-dependent mechanism acts to activate CD40 signaling/T-cell interactions in a CLL microenvironment and described a novel miR-29-TRAF4-CD40 signaling axis modulated by BCR activity.

Myeloid-derived suppressor cell subtypes differentially influence T-cell function, T-helper subset differentiation, and clinical course in CLL

Cancer pathogenesis involves the interplay of tumor- and microenvironment-derived stimuli. Here we focused on the influence of an immunomodulatory cell type, myeloid-derived suppressor cells (MDSCs), and their lineage-related subtypes on autologous T lymphocytes. Although MDSCs as a group correlated with an immunosuppressive Th repertoire and worse clinical course, MDSC subtypes (polymorphonuclear, PMN-MDSC, and monocytic, M-MDSCs) were often functionally discordant. In vivo, PMN-MDSCs existed in higher numbers, correlated with different Th-subsets, and more strongly associated with poor clinical course than M-MDSCs. In vitro, PMN-MDSCs were more efficient at blocking T-cell growth and promoted Th17 differentiation. Conversely, in vitro M-MDSCs varied in their ability to suppress T-cell proliferation, due to the action of TNFα, and promoted a more immunostimulatory Th compartment. Ibrutinib therapy impacted MDSCs differentially as well, since after initiating therapy, PMN-MDSC numbers progressively declined, whereas M-MDSC numbers were unaffected, leading to a set of less immunosuppressive Th cells. Consistent with this, clinical improvement based on decreasing CLL-cell numbers correlated with the decrease in PMN-MDSCs. Collectively, the data support a balance between PMN-MDSC and M-MDSC numbers and function influencing CLL disease course.

Chronic lymphocytic leukemia and second primary nonlymphoid malignancies: cytopathologic study of 17 cases

INTRODUCTION

Second primary nonlymphoid malignancies (SPNLM) have long been recognized as a complication of chronic lymphocytic leukemia (CLL).

MATERIALS AND METHODS

A search was made of our cytopathology database for cases of CLL that also contained a SPNLM.

RESULTS

Seventeen cases from 13 known CLL patients [M:F = 2.3:1; age range: 47-77 years, x = 67 years] met criteria for this study. SPNLMs consisted of different forms of metastatic carcinoma (10 patients) and malignant melanoma (3). Of 16 FNA biopsies and 1 pleural fluid, 82% had ancillary testing; 35% had the specimen subdivided for both flow cytometry (FCM) and immunohistochemistry (IHC). Lymph node was the most common site for FNA biopsy (12), followed by face (2), and soft tissue (2). Squamous cell carcinoma was the most common SPNLM (6), followed by melanoma (3), and there were single cases of adenocarcinoma, large cell neuroendocrine carcinoma, Merkel cell carcinoma, and papillary thyroid carcinoma. A correct specific cytologic diagnosis was made in 15 (88%) cases.

CONCLUSIONS

Cytopathology is highly proficient in recognizing SPNLM in CLL patients. Utilization of cytologic material for FCM and IHC is feasible, and extremely helpful in achieving diagnostic accuracy.