Single-cell Multiomics Analysis of Myelodysplastic Syndromes and Clinical Response to Hypomethylating Therapy

Alterations in epigenetic marks, such as DNA methylation, represent a hallmark of cancer that has been successfully exploited for therapy in myeloid malignancies. Hypomethylating agents (HMA), such as azacitidine, have become standard-of-care therapy to treat myelodysplastic syndromes (MDS), myeloid neoplasms that can evolve into acute myeloid leukemia. However, our capacity to identify who will respond to HMAs, and the duration of response, remains limited. To shed light on this question, we have leveraged the unprecedented analytic power of single-cell technologies to simultaneously map the genome and immunoproteome of MDS samples throughout clinical evolution. We were able to chart the architecture and evolution of molecular clones in precious paired bone marrow MDS samples at diagnosis and posttreatment to show that a combined imbalance of specific cell lineages with diverse mutational profiles is associated with the clinical response of patients with MDS to hypomethylating therapy.

SIGNIFICANCE

MDS are myeloid clonal hemopathies with a low 5-year survival rate, and approximately half of the cases do not respond to standard HMA therapy. Our innovative single-cell multiomics approach offers valuable biological insights and potential biomarkers associated with the demethylating agent efficacy. It also identifies vulnerabilities that can be targeted using personalized combinations of small drugs and antibodies.

Duvelisib Eliminates CLL B Cells, Impairs CLL-Supporting Cells, and Overcomes Ibrutinib Resistance in a Xenograft Model

PURPOSE

Inhibitors of Bruton's tyrosine kinase (BTKi) and PI3K (PI3Ki) have significantly improved therapy of chronic lymphocytic leukemia (CLL). However, the emergence of resistance to BTKi has introduced an unmet therapeutic need. Hence, we sought evidence for essential roles of PI3K-δi and PI3K-γi in treatment-naïve and BTKi-refractory CLL.

EXPERIMENTAL DESIGN

Responses to PI3K-δi, PI3K-γi, and the dual-inhibitor duvelisib in each B, T, and myeloid cell compartments of CLL were studied in vitro, and in a xenograft mouse model using primary cells from treatment-naïve and ibrutinib-resistant patients, and finally, in a patient with ibrutinib-resistant CLL treated with duvelisib.

RESULTS

We demonstrate the essential roles of PI3K-δ for CLL B-cell survival and migration, of PI3K-γ for T-cell migration and macrophage polarization, and of dual inhibition of PI3K-δ,γ for efficacious reduction of leukemia burden. We also show that samples from patients whose disease progressed on ibrutinib were responsive to duvelisib therapy in a xenograft model, irrespective of BTK mutations. In support of this, we report a patient with ibrutinib-resistant CLL, bearing a clone with BTK and PLCγ2 mutations, who responded immediately to single-agent duvelisib with redistribution lymphocytosis followed by a partial clinical remission associated with modulation of T and myeloid cells.

CONCLUSIONS

Our data define the mechanism of action whereby dual inhibition of PI3K-δ,γ affects CLL B-cell numbers and T and myeloid cell pro-leukemia functions and support the use of duvelisib as a valuable approach for therapeutic interventions, including for patients refractory to BTKi.

CLL stereotyped B-cell receptor immunoglobulin sequences are recurrent in the B-cell repertoire of healthy individuals: Apparent lack of central and early peripheral tolerance censoring

Introduction

The leukemic cells of patients with chronic lymphocytic leukemia (CLL) are often unique, expressing remarkably similar IGHV-IGHD-IGHJ gene rearrangements, “stereotyped BCRs”. The B-cell receptors (BCRs) on CLL cells are also distinctive in often deriving from autoreactive B lymphocytes, leading to the assumption of a defect in immune tolerance.

Results

Using bulk and single-cell immunoglobulin heavy and light chain variable domain sequencing, we enumerated CLL stereotype-like IGHV-IGHD-IGHJ sequences (CLL-SLS) in B cells from cord blood (CB) and adult peripheral blood (PBMC) and bone marrow (BM of healthy donors. CLL-SLS were found at similar frequencies among CB, BM, and PBMC, suggesting that age does not influence CLL-SLS levels. Moreover, the frequencies of CLL-SLS did not differ among B lymphocytes in the BM at early stages of development, and only re-circulating marginal zone B cells contained significantly higher CLL-SLS frequencies than other mature B-cell subpopulations. Although we identified CLL-SLS corresponding to most of the CLL major stereotyped subsets, CLL-SLS frequencies did not correlate with those found in patients. Interestingly, in CB samples, half of the CLL-SLS identified were attributed to two IGHV-mutated subsets. We also found satellite CLL-SLS among the same normal samples, and they were also enriched in naïve B cells but unexpectedly, these were ~10-fold higher than standard CLL-SLS. In general, IGHV-mutated CLL-SLS subsets were enriched among antigen-experienced B-cell subpopulations, and IGHV-unmutated CLL-SLS were found mostly in antigen-inexperienced B cells. Nevertheless, CLL-SLS with an IGHV-mutation status matching that of CLL clones varied among the normal B-cell subpopulations, suggesting that specific CLL-SLS could originate from distinct subpopulations of normal B cells. Lastly, using single-cell DNA sequencing, we identified paired IGH and IGL rearrangements in normal B lymphocytes resembling those of stereotyped BCRs in CLL, although some differed from those in patients based on IG isotype or somatic mutation.

Discussion

CLL-SLS are present in normal B-lymphocyte populations at all stages of development. Thus, despite their autoreactive profile they are not deleted by central tolerance mechanisms, possibly because the level of autoreactivity is not registered as dangerous by deletion mechanisms or because editing of L-chain variable genes occurred which our experimental approach could not identify.

Epigenetic profiling linked to multisystem inflammatory syndrome in children (MIS-C): A multicenter, retrospective study

BACKGROUND

Most children and adolescents infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain asymptomatic or develop a mild coronavirus disease 2019 (COVID-19) that usually does not require medical intervention. However, a small proportion of pediatric patients develop a severe clinical condition, multisystem inflammatory syndrome in children (MIS-C). The involvement of epigenetics in the control of the immune response and viral activity prompted us to carry out an epigenomic study to uncover target loci regulated by DNA methylation that could be altered upon the appearance of MIS-C.

METHODS

Peripheral blood samples were recruited from 43 confirmed MIS-C patients. 69 non-COVID-19 pediatric samples and 15 COVID-19 pediatric samples without MIS-C were used as controls. The cases in the two groups were mixed and divided into discovery (MIS-C = 29 and non-MIS-C = 56) and validation (MIS-C = 14 and non-MIS-C = 28) cohorts, and balanced for age, gender and ethnic background. We interrogated 850,000 CpG sites of the human genome for DNA methylation variants.

FINDINGS

The DNA methylation content of 33 CpG loci was linked with the presence of MIS-C. Of these sites, 18 (54.5%) were located in described genes. The top candidate gene was the immune T-cell mediator ZEB2; and others highly ranked candidates included the regulator of natural killer cell functional competence SH2D1B; VWA8, which contains a domain of the Von Willebrand factor A involved in the pediatric hemostasis disease; and human leukocyte antigen complex member HLA-DRB1; in addition to pro-inflammatory genes such as CUL2 and AIM2. The identified loci were used to construct a DNA methylation profile (EPIMISC) that was associated with MIS-C in both cohorts. The EPIMISC signature was also overrepresented in Kawasaki disease patients, a childhood pathology with a possible viral trigger, that shares many of the clinical features of MIS-C.

INTERPRETATION

We have characterized DNA methylation loci that are associated with MIS-C diagnosis. The identified genes are likely contributors to the characteristic exaggerated host inflammatory response observed in these patients. The described epigenetic signature could also provide new targets for more specific therapies for the disorder.

FUNDING

Unstoppable campaign of Josep Carreras Leukaemia Foundation, Fundació La Marató de TV3, Cellex Foundation and CERCA Programme/Generalitat de Catalunya.

Activated CLL cells regulate IL17F producing Th17 cells in miR155 dependent and outcome specific manners

Chronic lymphocytic leukemia (CLL) results from expansion of a CD5+ B-cell clone that requires interactions with other cell types, including T cells. Moreover, CLL patients have elevated circulating IL17A+ and IL17F+ CD4+ T cells (Th17s), with higher IL17A+Th17s correlating with better outcomes. We report that CLL Th17s express more miR155, a Th17 differentiation regulator, than control Th17s, despite naïve CD4+ T cell (TN) basal miR155 levels being similar in both. We also found that CLL cells directly regulate miR155 levels in TN, thereby affecting Th17 differentiation by documenting that: co-culturing TN with resting (Brest) or activated (Bact) CLL cells alters the magnitude and direction of T-cell miR155 levels; CLL Bact promote IL17A+ and IL17F+ T cell generation by a miR155-dependent mechanism, confirmed by miR155 inhibition; co-cultures of TN with CLL Bact lead to a linear correlation between the degree and direction of T-cell miR155 expression changes and IL17F production, but not IL17A; Bact-mediated changes in TN miR155 expression correlate with outcome, irrespective of IGHV mutation status, a strong prognostic indicator. Together, the results identify a previously unrecognized CLL Bact-dependent mechanism, upregulation of TN miR155 expression and subsequent enhancement of IL17F+ Th17 generation, that favors better clinical courses.

Biological and Molecular Factors Predicting Response to Adoptive Cell Therapies in Cancer

Adoptive cell therapy (ACT) constitutes a major breakthrough in cancer management that has expanded in the past years due to impressive results showing durable and even curative responses for some patients with hematological malignancies. ACT leverages antigen specificity and cytotoxic mechanisms of the immune system, particularly relying on the patient’s T lymphocytes to target and eliminate malignant cells. This personalized therapeutic approach exemplifies the success of the joint effort of basic, translational, and clinical researchers that has turned the patient’s immune system into a great ally in the search for a cancer cure. ACTs are constantly improving to reach a maximum beneficial clinical response. Despite being very promising therapeutic options for certain types of cancers, mainly melanoma and hematological malignancies, these individualized treatments still present several shortcomings, including elevated costs, technical challenges, management of adverse side effects, and a limited population of responder patients. Thus, it is crucial to discover and develop reliable and robust biomarkers to specifically and sensitively pinpoint the patients that will benefit the most from ACT as well as those at higher risk of developing potentially serious toxicities. Although unique readouts of infused cell therapy success have not yet been identified, certain characteristics from the adoptive cells, the tumor, and/or the tumor microenvironment have been recognized to predict patients’ outcome on ACT. Here, we comment on the importance of biomarkers to predict ACT chances of success to maximize efficacy of treatments and increase patients’ survival.

Epigenetic Profiling and Response to CD19 Chimeric Antigen Receptor T-Cell Therapy in B-Cell Malignancies

BACKGROUND

Chimeric antigen receptor (CAR) T cells directed against CD19 (CART19) are effective in B-cell malignancies, but little is known about the molecular factors predicting clinical outcome of CART19 therapy. The increasingly recognized relevance of epigenetic changes in cancer immunology prompted us to determine the impact of the DNA methylation profiles of CART19 cells on the clinical course.

METHODS

We recruited 114 patients with B-cell malignancies, comprising 77 patients with acute lymphoblastic leukemia and 37 patients with non-Hodgkin lymphoma who were treated with CART19 cells. Using a comprehensive DNA methylation microarray, we determined the epigenomic changes that occur in the patient T cells upon transduction of the CAR vector. The effects of the identified DNA methylation sites on clinical response, cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, event-free survival, and overall survival were assessed. All statistical tests were 2-sided.

RESULTS

We identified 984 genomic sites with differential DNA methylation between CAR-untransduced and CAR-transduced T cells before infusion into the patient. Eighteen of these distinct epigenetic loci were associated with complete response (CR), adjusting by multiple testing. Using the sites linked to CR, an epigenetic signature, referred to hereafter as the EPICART signature, was established in the initial discovery cohort (n = 79), which was associated with CR (Fisher exact test, P < .001) and enhanced event-free survival (hazard ratio [HR] = 0.36; 95% confidence interval [CI] = 0.19 to 0.70; P = .002; log-rank P = .003) and overall survival (HR = 0.45; 95% CI = 0.20 to 0.99; P = .047; log-rank P = .04;). Most important, the EPICART profile maintained its clinical course predictive value in the validation cohort (n = 35), where it was associated with CR (Fisher exact test, P < .001) and enhanced overall survival (HR = 0.31; 95% CI = 0.11 to 0.84; P = .02; log-rank P = .02).

CONCLUSIONS

We show that the DNA methylation landscape of patient CART19 cells influences the efficacy of the cellular immunotherapy treatment in patients with B-cell malignancy.

Risk Factors for Postpartum Depression During COVID-19 Pandemic: A Systematic Literature Review

INTRODUCTION

The COVID-19 pandemic has had a devastating worldwide effect on mental health. Recent studies correlate the spreading of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with symptoms of depression, most prominent in postpartum women. Our systematic literature review scope is to identify the risk factors and predictors for postpartum depression (PPD) and describe the steps that should be taken to help postpartum women. This study will help clinicians, researchers, and policymakers to elucidate the predictors of PPD during this pandemic and prevent these adverse outcomes in future crises.

METHODS

We conducted a systematic search by employing databases PubMed, Google Scholar, Scopus, and Embase to identify articles published before March 2021. About 463 publications were generated during our search process and from those, 36 were reviewed, summarized, and synthesized. Studies qualified the criteria if they (1) utilized qualitative or quantitative design, (2) explored the risk factors for PPD, and (3) were written in English. Quality evaluation of each study was achieved by using criteria set by Lincoln and Guba.

RESULTS

Prevalence of depression symptoms ranged from 7% to 80.8% in postpartum women during the SARS-COV 2 pandemic. The risk factors for PPD were classified into 6 major categories: socio-demographic, psychological, pre-existing pathology, metabolic factors, previous events of miscarriage, and media misinformation.

CONCLUSION

It is extremely vital to care for women's mental health during pregnancy and after childbirth during these unprecedented times. This review urges the need to design adequate interventions for this vulnerable population to prevent negative consequences of PPD.

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.

Musashi 2 influences chronic lymphocytic leukemia cell survival and growth making it a potential therapeutic target

Progression of chronic lymphocytic leukemia (CLL) results from the expansion of a small fraction of proliferating leukemic B cells. When comparing the global gene expression of recently divided CLL cells with that of previously divided cells, we found higher levels of genes involved in regulating gene expression. One of these was the oncogene Musashi 2 (MSI2), an RNA-binding protein that induces or represses translation. While there is an established role for MSI2 in normal and malignant stem cells, much less is known about its expression and role in CLL. Here we report for the first time ex vivo and in vitro experiments that MSI2 protein levels are higher in dividing and recently divided leukemic cells and that downregulating MSI2 expression or blocking its function eliminates primary human and murine CLL and mature myeloid cells. Notably, mature T cells and hematopoietic stem and progenitor cells are not affected. We also confirm that higher MSI2 levels correlate with poor outcome markers, shorter time-to-first-treatment, and overall survival. Thus, our data highlight an important role for MSI2 in CLL-cell survival and proliferation and associate MSI2 with poor prognosis in CLL patients. Collectively, these findings pinpoint MSI2 as a potentially valuable therapeutic target in CLL.

A Detailed Analysis of Parameters Supporting the Engraftment and Growth of Chronic Lymphocytic Leukemia Cells in Immune-Deficient Mice

Patient-derived xenograft models of chronic lymphocytic leukemia (CLL) can be created using highly immunodeficient animals, allowing analysis of primary tumor cells in an in vivo setting. However, unlike many other tumors, CLL B lymphocytes do not reproducibly grow in xenografts without manipulation, proliferating only when there is concomitant expansion of T cells. Here we show that in vitro pre-activation of CLL-derived T lymphocytes allows for a reliable and robust system for primary CLL cell growth within a fully autologous system that uses small numbers of cells and does not require pre-conditioning. In this system, growth of normal T and leukemic B cells follows four distinct temporal phases, each with characteristic blood and tissue findings. Phase 1 constitutes a period during which resting CLL B cells predominate, with cells aggregating at perivascular areas most often in the spleen. In Phase 2, T cells expand and provide T-cell help to promote B-cell division and expansion. Growth of CLL B and T cells persists in Phase 3, although some leukemic B cells undergo differentiation to more mature B-lineage cells (plasmablasts and plasma cells). By Phase 4, CLL B cells are for the most part lost with only T cells remaining. The required B-T cell interactions are not dependent on other human hematopoietic cells nor on murine macrophages or follicular dendritic cells, which appear to be relatively excluded from the perivascular lymphoid aggregates. Notably, the growth kinetics and degree of anatomic localization of CLL B and T cells is significantly influenced by intravenous versus intraperitoneal administration. Importantly, B cells delivered intraperitoneally either remain within the peritoneal cavity in a quiescent state, despite the presence of dividing T cells, or migrate to lymphoid tissues where they actively divide; this dichotomy mimics the human condition in that cells in primary lymphoid tissues and the blood are predominately resting, whereas those in secondary lymphoid tissues proliferate. Finally, the utility of this approach is illustrated by documenting the effects of a bispecific antibody reactive with B and T cells. Collectively, this model represents a powerful tool to evaluate CLL biology and novel therapeutics in vivo.

Chronic lymphocytic leukemia-like monoclonal B-cell lymphocytosis exhibits an increased inflammatory signature that is reduced in early-stage chronic lymphocytic leukemia

Several studies in chronic lymphocytic leukemia (CLL) patients have reported impaired immune cell functions, which contribute to tumor evasion and disease progression. However, studies on CLL-like monoclonal B-cell lymphocytosis (MBL) are scarce. In the study described here, we characterized the immune environment in 62 individuals with clinical MBL, 56 patients with early-stage CLL, and 31 healthy controls. Gene expression arrays and quantitative reverse transcription polymerase chain reaction were performed on RNA from CD4⁺ peripheral blood cells; serum cytokines were measured with immunoassays; and HLA-DR expression on circulating monocytes, as well as the percentages of Th1, cytotoxic, exhausted, and effector CD4⁺ T cells, were evaluated by flow cytometry. In addition, cell cultures of clonal B cells and CD14-enriched or -depleted cell fractions were performed. Strikingly, MBL and early-stage CLL differed in pro-inflammatory signatures. An increased inflammatory drive orchestrated mainly by monocytes was identified in MBL, which exhibited enhanced phagocytosis, pattern recognition receptors, interleukin-8 (IL8), HMGB1, and acute response signaling pathways and increased pro-inflammatory cytokines (in particular IL8, interferon γ [IFNγ], and tumor necrosis factor α). This inflammatory signature was diminished in early-stage CLL (reduced IL8 and IFNγ levels, IL8 signaling pathway, and monocytic HLA-DR expression compared with MBL), especially in those patients with mutations in IGHV genes. Additionally, CD4⁺ T cells of MBL and early-stage CLL exhibited a similar upregulation of Th1 and cytotoxic genes and expanded CXCR3⁺ and perforin⁺ CD4⁺ T cells, as well as PD1⁺ CD4⁺ T cells, compared with controls. Cell culture assays disclosed tumor-supporting effects of monocytes similarly observed in MBL and early-stage CLL. These novel findings reveal differences in the inflammatory environment between MBL and CLL, highlighting an active role for antigen stimulation in the very early stages of the disease, potentially related to malignant B-cell transformation.

Critical molecular pathways in CLL therapy

Chronic lymphocytic leukemia (CLL), the most frequent type of leukemia in western countries, is characterized by the progressive accumulation in blood, bone marrow and lymphoid tissues of monoclonal B lymphocytes with a characteristic immunophenotype. Despite advances in therapy and improved outcome, in most instances CLL is an incurable disorder. Signaling via the B-cell receptor (BCR), the upregulation of anti-apoptotic proteins, and the cross-talk between CLL cells and microenvironment constitute key factors in the pathogenesis of CLL. Currently, inhibitors of kinases like BTK or PI3K blocking BCR signaling, and molecules that mimic the BH3 domain to compete with BCL-2 are established tools in the treatment of CLL. As the complex biology of CLL is rapidly unfolding, the number of small molecules targeting CLL molecular pathways is increasing and it is likely that they will further improve the outcome of patients with this form of leukemia.

Novel Method for High-Throughput Full-Length IGHV-D-J Sequencing of the Immune Repertoire from Bulk B-Cells with Single-Cell Resolution

Efficient and accurate high-throughput DNA sequencing of the adaptive immune receptor repertoire (AIRR) is necessary to study immune diversity in healthy subjects and disease-related conditions. The high complexity and diversity of the AIRR coupled with the limited amount of starting material, which can compromise identification of the full biological diversity makes such sequencing particularly challenging. AIRR sequencing protocols often fail to fully capture the sampled AIRR diversity, especially for samples containing restricted numbers of B lymphocytes. Here, we describe a library preparation method for immunoglobulin sequencing that results in an exhaustive full-length repertoire where virtually every sampled B-cell is sequenced. This maximizes the likelihood of identifying and quantifying the entire IGHV-D-J repertoire of a sample, including the detection of rearrangements present in only one cell in the starting population. The methodology establishes the importance of circumventing genetic material dilution in the preamplification phases and incorporates the use of certain described concepts: (1) balancing the starting material amount and depth of sequencing, (2) avoiding IGHV gene-specific amplification, and (3) using Unique Molecular Identifier. Together, this methodology is highly efficient, in particular for detecting rare rearrangements in the sampled population and when only a limited amount of starting material is available.

FcγRIIb expression in early stage chronic lymphocytic leukemia

In normal B-cells, B-cell antigen receptor (BCR) signaling can be negatively regulated by the low-affinity receptor FcγRIIb (CD32b). To better understand the role of FcγRIIb in chronic lymphocytic leukemia (CLL), we correlated its expression on 155 samples from newly-diagnosed Binet A patients with clinical characteristics and outcome. FcγRIIb expression was similar in normal B-cells and leukemic cells, this being heterogenous among patients and within CLL clones. FcγRIIb expression did not correlate with well known prognostic markers [disease stage, serum beta-2 microglobulin (B2M), IGHV mutational status, expression of ZAP-70 and CD38, and cytogenetics] except for a weak concordance with CD49d. Moreover, patients with low FcγRIIb expression (69/155, 44.5%) required therapy earlier than those with high FcγRIIb expression (86/155, 55.5%) (median 151.4 months vs. not reached; p=.071). These results encourage further investigation on the role of FcγRIIb in CLL biology and prognostic significance in larger series of patients.

Chronic lymphocytic leukemia cells diversify and differentiate in vivo via a nonclassical Th1-dependent, Bcl-6-deficient process

Xenografting primary tumor cells allows modeling of the heterogeneous natures of malignant diseases and the influences of the tissue microenvironment. Here, we demonstrate that xenografting primary chronic lymphocytic leukemia (CLL) B lymphocytes with activated autologous T cells into alymphoid mice results in considerable CLL B cell division and sizable T cell expansion. Nevertheless, most/all CD5⁺CD19⁺ cells are eventually lost, due in part to differentiation into antibody-secreting plasmablasts/plasma cells. CLL B cell differentiation is associated with isotype class switching and development of new IGHV-D-J mutations and occurs via an activation-induced deaminase-dependent pathway that upregulates IRF4 and Blimp-1 without appreciable levels of the expected Bcl-6. These processes were induced in IGHV-unmutated and IGHV-mutated clones by Th1-polarized T-bet⁺ T cells, not classical T follicular helper (Tfh) cells. Thus, the block in B cell maturation, defects in T cell action, and absence of antigen-receptor diversification, which are often cardinal characteristics of CLL, are not inherent but imposed by external signals and the microenvironment. Although these activities are not dominant features in human CLL, each occurs in tissue proliferation centers where the mechanisms responsible for clonal evolution operate. Thus, in this setting, CLL B cell diversification and differentiation develop by a nonclassical germinal center-like reaction that might reflect the cell of origin of this leukemia.

Epigenetic regulation of microRNA expression in Hodgkin lymphoma

Epigenetic mechanisms are crucial for the inactivation of key genes related to the survival of Hodgkin lymphoma (HL) cells, and methylation is a frequent epigenetic mechanism of microRNA silencing. We have examined the methylation-induced silencing of tumor suppressor microRNAs in HL cell lines and confirmed our results in patient lymph nodes. In addition, we evaluated the in vitro effectiveness of 5-aza-2-deoxycytidine (5-Aza-dC) in HL cell lines. Ten microRNAs containing CpG islands in their promoter region were re-expressed in both the L-428 and L-1236 cell lines. Interestingly, miR-34a and miR-203, both known tumor suppressor microRNAs, were found to be methylated in cell lines and in patient samples. 5-Aza-dC treatment resulted in a dose-dependent antiproliferative effect at 72 h in all the HL cell lines. In summary, 5-Aza-dC treatment of HL cell lines inhibits proliferation at high doses and produces re-expression of the tumor suppressor microRNAs at low-intermediate doses.

Role of miR-200 family members in survival of colorectal cancer patients treated with fluoropyrimidines

BACKGROUND AND OBJECTIVES

Surgery is the standard treatment for colorectal cancer (CRC), and adjuvant chemotherapy has been shown to be effective in stage III but less so in stage II. We have analyzed the expression of the miR-200 family in tissue samples from resected CRC patients and correlated our findings with survival to adjuvant treatment with fluoropyrimidines.

METHODS

Tumor tissue samples were obtained from 127 surgically resected patients with stage I-III CRC. miRNA detection was performed using TaqMan MicroRNA assays.

RESULTS

High levels of miR-200a and miR-200c were associated with longer overall survival, while high levels of miR-429 correlated with longer overall and disease-free survival (DFS). In the subgroup of 56 patients treated with fluoropyrimidines and in the smaller subgroup of 32 stage II patients treated with fluoropyrimidines, those with high levels of miR-200a, miR-200c, miR-141, or miR-429 had significantly longer overall and DFS. Low miR-429 levels were identified as an independent prognostic marker. High levels of miR-429 combined with 5-fluorouracil inhibited cell invasion in LOVO cells.

CONCLUSIONS

miR-200a, miR-200c, miR-141, and miR-429 expression levels may identify CRC patients, including those with stage II disease, who are most likely to benefit from adjuvant chemotherapy.

B cell activation through CD40 and IL4R ligation modulates the response of chronic lymphocytic leukaemia cells to BAFF and APRIL

The two tumour necrosis factor family proteins BAFF (TNFSF13B) and APRIL (TNFSF13) and their receptors [BAFF-R (TNFRSF13C), TACI (TNFRSF13B), BCMA (TNFRSF17)] play a critical role in the survival of normal B cells. The sensitivity of normal B cells to BAFF and APRIL can be modulated by signals regulated by their receptors. This modulation, however, has not been extensively investigated in chronic lymphocytic leukaemia (CLL) cells. We evaluated the expression, regulation and signalling of BAFF and APRIL receptors in normal and in CLL cells upon stimulation through CD40+IL4R and BCR. We further analysed the prognostic value of BAFF and APRIL receptors expression in patients with CLL. BCMA expression was significantly higher on CLL cells than on normal B cells. BCR and CD40+IL4R stimulation promoted an increase in TACI and BCMA expression, cell viability and activation in normal B cells. A similar effect was observed in CLL cells after CD40+IL4R but not BCR stimulation. BCMA expression correlated with unmutated IGHV genes, poor-risk cytogenetics, and short progression-free survival. These findings further characterize the link between CD40+IL4R regulatory signals, BAFF, APRIL and their receptors and the survival of leukaemic cells and clinical features of CLL.

MicroRNA expression in chronic lymphocytic leukemia developing autoimmune hemolytic anemia

Chronic lymphocytic leukemia (CLL) is frequently associated with autoimmune hemolytic anemia (AIHA). However, the mechanisms governing the association between CLL and AIHA are poorly understood. MicroRNAs (miRNAs) have been associated with different clinico-biological forms of CLL and are also known to play a substantial role in autoimmunity. However, there are no studies correlating miRNA expression with the likelihood that patients with CLL will develop AIHA. In this study, we found that malignant B-cells from patients with CLL subsequently developing AIHA present nine down-regulated (i.e. miR-19a, miR-20a, miR-29c, miR-146b-5p, miR-186, miR-223, miR-324-3p, miR-484 and miR-660) miRNAs. Interestingly, two of these miRNAs (i.e. miR-20a and miR-146b-5p) are involved in autoimmune phenomena, and one (i.e. miR-146b-5p) in both autoimmunity and CLL. Furthermore, we demonstrated that miR-146b-5p modulates CD80, a molecule associated with the B-T-cell synapse and in restoration of the antigen presenting cell capacity of CLL cells.

Impact of MiRSNPs on survival and progression in patients with multiple myeloma undergoing autologous stem cell transplantation

PURPOSE

A distinctive new group of polymorphisms is constituted by single-nucleotide polymorphism (SNP) in miRNA processing machinery in miRNA precursor molecules and in miRNA-binding sites, known as miRSNPs. The aim of this study was to ascertain the prognostic impact of six miRSNPs in patients with multiple myeloma and analyze the functional consequences.

EXPERIMENTAL DESIGN

One hundred and thirty-seven patients with chemosensitive multiple myeloma (73M/64F) intensified with autologous stem cell transplantation (ASCT) were studied. The median follow-up was 4 years. The genes and SNPs evaluated in genomic DNA by allelic discrimination were KRT81 (rs3660), AFF1 (rs17703261), FAM179b (rs1053667), and MIR196A2 (rs11614913) for miRNA target genes and TRBP (rs784567) and XPO5 (rs11077) for miRNA biogenesis pathway.

RESULTS

Overall survival (OS) was significantly longer in patients with KRT81 rs3660 C/C variant (P = 0.037). Functional analysis showed that the presence of C variant in KRT81 3' untranslated region (UTR) is related with a reduction of the protein levels. Moreover, the reduction of KRT81 protein levels by siRNA in multiple myeloma cell lines is related to a decreased proliferation. On the other hand, OS was significantly longer in patients with C/C or A/C variant in XPO5 rs11077 (P = 0.012). There was also a significantly longer progression-free survival (PFS) for this SNP (P = 0.013). This SNP retained its prognostic impact on PFS and OS in a multivariate regression analysis (P = 0.028 and P = 0.014, respectively).

CONCLUSION

This is the first report that relates miRSNPs with prognosis in multiple myeloma either in a keratin gene (KRT81), target of diverse miRNA multiple myeloma clusters, or in the miRNA biogenesis pathway-related protein exportin-5.

Combined analysis of levels of serum B-cell activating factor and a proliferation-inducing ligand as predictor of disease progression in patients with chronic lymphocytic leukemia

B-cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are regulators of normal B-cell development and survival. We investigated their role in chronic lymphocyticleukemia (CLL) by relating serum protein levels and CLL cell mRNA expression with clinical factors and disease progression. In patients with CLL, BAFF serum levels were significantly lower than in controls (0.64 ng/mL vs. 0.77 ng/mL, p = 0.014), and APRIL serum levels were significantly higher (4.10 ng/mL vs. 1.84 ng/mL, p = 0.041). CLL cells expressed BAFF and APRIL mRNA at lower levels than normal B-cells. Low BAFF serum levels were significantly correlated with a high blood lymphocyte count and advanced clinical stage, whereas APRIL levels were correlated with CD38 expression. In a multivariate analysis, the combined analysis of BAFF and APRIL serum levels emerged as an independent predictor of disease progression.

Chronic lymphocytic leukemia and autoimmunity: a systematic review

Chronic lymphocytic leukemia is frequently associated with immune disturbances. The relationship between chronic lymphocytic leukemia and autoimmune cytopenias, particularly autoimmune hemolytic anemia and immune thrombocytopenia, is well established. The responsible mechanisms, particularly the role of leukemic cells in orchestrating the production of polyclonal autoantibodies, are increasingly well understood. Recent studies show that autoimmune cytopenia is not necessarily associated with poor prognosis. On the contrary, patients with anemia or thrombocytopenia due to immune mechanisms have a better outcome than those in whom these features are due to bone marrow infiltration by the disease. Moreover, fears about the risk of autoimmune hemolysis following single agent fludarabine may no longer be appropriate in the age of chemo-immunotherapy regimens. However, treatment of patients with active hemolysis may pose important problems needing an individualized and clinically sound approach. The concept that autoimmune cytopenia may precede the leukemia should be revisited in the light of recent data showing that autoimmune cytopenia may be observed in monoclonal B-cell lymphocytosis, a condition that can only be detected by using sensitive flow cytometry techniques. On the other hand, there is no evidence of an increased risk of non-hemic autoimmune disorders in chronic lymphocytic leukemia. Likewise, there is no epidemiological proof of an increased risk of chronic lymphocytic leukemia in patients with non-hemic autoimmunity. Finally, since immune disorders are an important part of chronic lymphocytic leukemia, studies aimed at revealing the mechanisms linking the neoplastic and the immune components of the disease should help our understanding of this form of leukemia.

Lestaurtinib inhibition of the Jak/STAT signaling pathway in hodgkin lymphoma inhibits proliferation and induces apoptosis

Standard cytotoxic chemotherapy for Hodgkin Lymphoma (HL) has changed little in 30 years; the treatment for patients with relapsed or refractory disease remains challenging and novel agents are under development. JAK/STAT constitutive activation plays an important role in the pathogenesis of HL. Lestaurtinib is an orally bioavailable multikinase inhibitor that has recently been shown to inhibit JAK2 in myeloproliferative disorders. The potential role of Lestaurtinib in HL therapy is unknown. We have analyzed the effect of Lestaurtinib treatment in five HL cell lines from refractory patients, L-428, L-1236, L-540, HDML-2 and HD-MY-Z. At 48 h, a dose-dependent cell growth inhibition (23%–66% at 300 nM) and apoptotic increment (10%–64% at 300 nM) were observed. Moreover, Lestaurtinib inhibited JAK2, STAT5 and STAT3 phosphorylation and reduced the mRNA expression of its downstream antiapoptotic target Bcl-xL. In addition, we have analyzed the effect of Lestaurtinib treatment in lymph nodes from four classic HL patients. We observed a decrease in cell viability at 24 hours of treatment in three patients (mean decrease of 27% at 300 nM). Our findings provide, for the first time, a molecular rationale for testing JAK2 inhibitors, specifically Lestaurtinib, in HL patients.

Mediastinal aortosympathetic paraganglioma: report of two cases

Thoracic paragangliomas or extra-adrenal pheochromocytomas are uncommon neoplasms that may arise from the extra-adrenal paraganglia. Paragangliomas arising in the anterior mediastinum are most frequent and are related to the base of the heart. Paragangliomas of the posterior mediastinum are most infrequent, and arise from aorticosympathetic paraganglia. We present two cases of posterior mediastinum paraganglioma. Complete tumor resection was done through posterolateral thoracotomy. The diagnosis of aorticosympathectic paraganglioma was established by histologic examination.

Loss of PPAR gamma in immune cells impairs the ability of abscisic acid to improve insulin sensitivity by suppressing monocyte chemoattractant protein-1 expression and macrophage infiltration into white adipose tissue

Abscisic acid (ABA) is a natural phytohormone and peroxisome proliferator-activated receptor gamma (PPARgamma) agonist that significantly improves insulin sensitivity in db/db mice. Although it has become clear that obesity is associated with macrophage infiltration into white adipose tissue (WAT), the phenotype of adipose tissue macrophages (ATMs) and the mechanisms by which insulin-sensitizing compounds modulate their infiltration remain unknown. We used a loss-of-function approach to investigate whether ABA ameliorates insulin resistance through a mechanism dependent on immune cell PPARgamma. We characterized two phenotypically distinct ATM subsets in db/db mice based on their surface expression of F4/80. F4/80(hi) ATMs were more abundant and expressed greater concentrations of chemokine receptor (CCR) 2 and CCR5 when compared to F4/80(lo) ATMs. ABA significantly decreased CCR2(+) F4/80(hi) infiltration into WAT and suppressed monocyte chemoattractant protein-1 (MCP-1) expression in WAT and plasma. Furthermore, the deficiency of PPARgamma in immune cells, including macrophages, impaired the ability of ABA to suppress the infiltration of F4/80(hi) ATMs into WAT, to repress WAT MCP-1 expression and to improve glucose tolerance. We provide molecular evidence in vivo demonstrating that ABA improves insulin sensitivity and obesity-related inflammation by inhibiting MCP-1 expression and F4/80(hi) ATM infiltration through a PPARgamma-dependent mechanism.

[Results of high bilateral endoscopic thoracic sympathectomy and sympatholysis in the treatment of primary hyperhidrosis: a study of 1016 procedures]

OBJECTIVE

Thoracic sympatholysis and sympathectomy are the current standard treatments for primary hyperhidrosis. In this study, we evaluated the incidence of peri- and postoperative complications associated with these procedures.

PATIENTS AND METHODS

From 1996 to 2004, 520 consecutive patients (364 women), with a mean age of 26.8 years, were treated for primary hyperhidrosis at our hospital. The procedure was bilateral in all but 24 cases. The 484 patients in the sympatholysis group underwent a single intervention while the 36 patients in the sympathectomy group underwent 2 separate interventions.

RESULTS

No deaths occurred. Anhidrosis of the target area was achieved in 97.6% of patients while 2.2% experienced hypohidrosis. In 0.2% of the cases, the procedure was initially unsuccessful and a second intervention was required. The mean duration of hospital stay was 72 hours for patients in the sympathectomy group and 17 hours for the sympatholysis group. Serious intraoperative complications requiring conversion to thoracotomy were recorded in 0.2% of patients. Postoperative complications--of which pneumothorax was the most common--occurred in 5.2% of the cases (in 22.5% of the sympathectomy group and 3.55% of the sympatholysis group). Compensatory hyperhidrosis occurred in 48.4% of the patients, excessive dryness of the hands and palpebral ptosis in 0.38%, and gustatory sweating in 0.9%. The degree of patient satisfaction was quite high (88.5%) and only 2.3% were very unsatisfied.

CONCLUSIONS

Given the results obtained, we can conclude that both sympatholysis and sympathectomy are appropriate treatments for hyperhidrosis. Nonetheless, because sympatholysis is both easier to perform and less aggressive, we consider it the treatment of choice for primary hyperhidrosis.

Thoracic sympathicolysis for primary hyperhidrosis: a review of 918 procedures

BACKGROUND

Bilateral upper thoracic sympathectomy or sympathicolysis, currently the standard treatment for palmar or axillary hyperhidrosis, is regarded as a safe procedure. This study evaluates the quantitative and qualitative incidence of intraoperative and postoperative complications resulting from bilateral thoracic sympathicolysis.

METHODS

From 1996 to 2004, 458 consecutive patients with primary hyperhidrosis underwent surgery. These patients comprised 143 men (31.2%) and 315 women (68.7%) with a mean age of 26 years (range, 14-52 years). In all but seven cases, the procedure was bilaterally synchronous.

RESULTS

No mortality was recorded. The anhydrosis rate was 97.4%, with a hypohidrosis rate of 2.4% and a failure rate of 0.2%. The latter was resolved with reintervention. The mean hospital stay was 17 h. The rate of major perioperative complications with conversion to thoracotomy was 0.4%. The overall rate of postoperative complications was 3.6%. The complications and rates observed were as follows: pneumothorax (2.06%), subcutaneous emphysema (1.08%), pleural bleeding (0.2%), hemothorax (0.1%), and atelectasis (0.1%). Compensatory hyperhidrosis was observed in 48.4% of the patients, but the sensation of compensatory hyperhidrosis was reported in 85.6% of the cases. Excessive dryness of the hands was reported in 0.38%, Horner's syndrome in 0.32%, and gustatory hyperhidrosis in 1.1% of the cases. The overall satisfaction rate was 88.5%.

CONCLUSIONS

The results suggest that endoscopic bilateral thoracic sympathicolysis is an effective method for managing primary hyperhidrosis, especially severe palmar hyperhidrosis, but it is necessary to inform patients fully concerning the undesirable effects.

Tracheal and cricotracheal resection for laryngotracheal stenosis: experience in 54 consecutive cases

OBJECTIVE

Partial tracheal resection (Küster operation (KO)) and cricotracheal resection (Pearson operation (PO)) are currently the standard operative techniques in the curative treatment of tracheal and cricotracheal stenosis, respectively. This study aims to analyze the outcomes of tracheal and cricotracheal resection when a specific protocol is applied.

METHODS

Between 1990 and 2004 we treated 54 patients with laryngotracheal stenosis. The mean age was 44.9 years with a sex ratio of 1:1. All patients were treated according to the random protocol "Lesions of the main airway (MA) protocol," which considers the following stenosis variables: stage of development (S), caliber (C), and length (L). We performed 38 Küster operations, 14 Pearson operations, and 2 combined Pearson-Küster-Rethi operations (ROs).

RESULTS

Overall mortality of the series was 1.85%, with a specific morbidity of 27.7%. A total of 96.2% of patients were cured (85.6% of Pearson operation and 100% of Küster operation). We performed 3.7% re-interventions (14.2% of Pearson operation and 0% of Küster operation), and the failure rate was 3.7% (14.4% of Pearson operation and 0% of Küster operation). We had 27.5% who had postoperative complications (28.5% of Pearson operation and 26.3% of Küster operation). The most frequent complications were restenosis (14.2%), granulation tissue (13.1%), edema (10.5%), anastomotic dehiscence (7.1%), and tracheoesophageal fistula (7.1%). In terms of the SCL variables, significant differences were only observed with respect to morbidity between the S4 group and the other cases without tracheoesophageal fistula in the Küster operation group; we found no differences in Pearson operation.

CONCLUSIONS

Application of the Main Airway protocol allowed development of a strategy for the surgical treatment of main airway stenosis. This, in turn, enabled a strict selection of cases and meticulous preoperative preparation that, coupled with a highly effective surgical technique, led to excellent outcomes with minimal sequel. The presence of tracheoesophageal fistula could increase the complications.

[Primary hyperhidrosis and anxiety: a prospective preoperative survey of 158 patients]

OBJECTIVE

To determine the location of hyperhidrosis, the accompanying signs and symptoms, and patient anxiety assessed on 2 scales and standardized psychometric instruments.

PATIENTS AND METHODS

A prospective study of patients with hyperhidrosis was carried out between September 1, 2001 and June 30, 2003 with a self-administered preoperative questionnaire. The variables studied included the location of hyperhidrosis, the accompanying signs and symptoms, and the self-reported degree of anxiety and perception of its effect on daily life assessed by the State-Trait Anxiety Inventory (STAI) and a questionnaire designed in our department.

RESULTS

Palmar hyperhidrosis was reported by 93.6% of patients, plantar by 70.2%, axillary by 66.4%, facial by 12.1%, groin by 8.2%, chest by 5%, and abdominal by 2%. While more than 50% of the patients reported facial blushing and palpitations as accompanying signs and symptoms, approximately 30% experienced epigastric pain, trembling, and headaches. Over half of the patients reported that their anxiety was incapacitating, and a mere 1.2% experienced none at all. STAI scores were similar to those of the general population whereas scores on our department's questionnaire reflected those of the self-reported anxiety ratings.

CONCLUSIONS

Primary hyperhidrosis is a disorder in which excessive sweating occurs mainly, but not exclusively, on the palms. The condition is accompanied by signs and symptoms typical of autonomic nervous system hyperactivity and by a degree of anxiety that has an incapacitating effect on normal life, although that anxiety is not detected by the STAI questionnaire alone.

[Compensatory sweating after upper thoracic sympathectomy. Prospective study of 123 cases]

OBJECTIVE

The most unpleasant consequence of upper thoracic sympathectomy is compensatory sweating (CS). De-pending on the series, the incidence of CS ranges from 24% to 85%. The aim of this study was to determine the relation between CS and the following factors: distribution of hyperhidrosis, procedure performed (unilateral, synchronic bilateral, or sequential bilateral), and number of sympathetic ganglia eliminated. In addition, the degree of patient satisfaction was recorded as objectively as possible.

PATIENTS AND METHODS

Prospective study of 123 patients who underwent upper thoracic sympathectomy for palmar and/or axillary hyperhidrosis between 1 January, 1996 and 1 June, 2002 at our unit. All patients completed a questionnaire on symptoms 8 weeks before and after surgery to deter-mine postoperative changes in distribution of the hyperhidrosis and the overall degree of satisfaction on a scale of 0 to 4.

RESULTS

The sensation of CS was reported by 86.1% of the patients. When asked to relate this sensation to changes in sweating intensity in specific parts of the body, 46.54% reported CS and 48.37% no change. The trunk was the only region where statistically significant increases in CS occurred; in the feet, a decrease in sweating was noted. No differences in CS were observed with respect to the type of surgery or the number of sympathetic ganglia eliminated. The overall results were considered very satisfactory or quite satisfactory by 84.55% of the patients, while 4.88% were very dissatisfied.

CONCLUSIONS

Although CS is a side effect of upper thoracic sympathectomy, not all patients are affected by it. Significant CS occurs mainly in the back, chest, and abdomen. Neither the type of intervention nor the number of ganglia eliminated has an effect on CS. This side effect notwithstanding, overall satisfaction with the treatment is very satisfactory given that the palmar hyperhidrosis is eliminated.

[Primary hyperhidrosis: prospective study in 338 patients]

BACKGROUND AND OBJECTIVE

The objective of this report is to study the clinical aspects of the patients with primary hyperhidrosis (PH) and the social and occupational distressing condition.

PATIENTS AND METHOD

From January 1998 to October 2002, 338 patients with PH completed a preoperative questionnaire to register: age, gender, profession, associated diseases, familiar hyperhidrosis history, sweating location, associated dermatological lesions and social embarrassesment. 179 patients were asked about their general symptomatology.

RESULTS

In 86% of the patients PH started during infancy, 71.5% were female (mean age 28.8 years). A few patients had others diseases and 42.5% had some associated dermatological lesions. In 47.9% of the patients there is family history of PH. 96.4% reported palmar hyperhidrosis, 80.7% plantar PH and 71.3% reported axillary PH, being less frequent in others regions of the body. The most frequent clinical founding associated is facial blushing in 60.3%, 52.3% heart palpitations, 48% muscle stress, 31.8% reported trembling of the hands and 30,8% headache. In reference to social embarrassesment, we observe that relations between friends and professional environment are the most problematic situation.

CONCLUSIONS

PH is a pathologic condition starting in infancy, family history of PH is frequent and most patients have some associated dermatological lesions. Excessive sweating is especially common in palms but no exclusively of this region as it extends to others regions with the same intensity. It can be associated with symptomatology suggestive of hyperexcitability of the sympathetic activity like facial blushing, trembling or headache, symptoms difficult to consider whether they are cause or consequence.

[Histopathological changes in sympathetic ganglia of patients treated surgically for palmar-axillary hyperhidrosis. A study of 55 biopsies]

INTRODUCTION

Primary palmar hyperhidrosis (PPH) mainly affects the sympathetic ganglia. This study aims to analyze the histopathological changes in the sympathetic ganglia of patients with PPH.

MATERIAL AND METHOD

We studied 55 tissue samples from 35 patients with PPH who underwent T2-T3 gangliectomy for definitive treatment of their disease, analyzing the presence of inflammation, chromatolysis and lipofuscin accumulation. Findings were analyzed in relation to age, compensatory sweating and type of surgery: unilateral, synchronic bilateral or sequential bilateral.

RESULTS

We found inflammation in 5.5%, chromatolysis in 61.8% and lipofuscin accumulation in 41.8% of the samples. Chromatolysis and lipofuscin were found without inflammation in 32.1%. Chromatolysis and lipofuscin accumulation were each found in 60% of the samples from synchronic bilateral sympathectomies. However, those percentages decreased between the first and second sympathectomies in sequential procedures, such that chromatolysis was found in 71.4% of first-procedure samples and 42.8% of second-procedure samples; the rates for lipofuscin accumulation changed from 64.2% to 14.2%. Although findings were unrelated to age, they did correlate with compensatory sweating, which was found in 79.7% of patients undergoing synchronic bilateral sympathectomy, 78.5% of sequential bilateral sympathectomy patients and only 56.25% of unilateral sympathectomy patients.

CONCLUSIONS

Neuronal death and lipofuscin accumulation unrelated to inflammation are evident in sympathetic ganglia from patients with PPH. Such changes are atypical for a group of patients whose mean age is 29 years, unless such lesions are the result of functional hyperstimulation. Surgery performed sequentially does not lead to overloading of contralateral T2-T3 ganglia; on the contrary, decreased injury is evident.