The applications of Wearable Cardioverter Defibrillators in Heart Failure and beyond.

Abstract: Wearable cardioverter defibrillator has revealed a crucial device both in patients with a clear indication of ICD implantation but with temporary contraindications or in expectation of a diagnosis, considering that its use should be individualized.

Levosimendan for acute right heart failure in COVID-19: another arrow in our quiver?

OBJECTIVE: SARS-CoV-2 infection is associated with a higher risk of acute right heart failure (RHF) due to primary right ventricle (RV) dilation and systemic inflammatory response, which in turn lead to microvascular and cardiomyocytes dysfunction, local hypoxia and multi-organ failure. In this clinical setting, levosimendan could be a viable therapy thanks to its right-heart tropism and its additional pleiotropic properties. CASE REPORT: We present the case of a 72 years-old man with positive nasopharyngeal swab for SARS-CoV-2 infection, mild pulmonary involvement and clinical signs of new-onset RHF. We started a 12-hour levosimendan cycle to improve RV performance and reduce cardiac filling pressures. RESULTS: We obtained a net clinical benefit in terms of acute RHF-related signs and symptoms, progressive renal and liver function improvement and concomitant reduction of high-sensitivity C-Reactive Protein and Interleukin-6 (IL-6) levels. CONCLUSIONS: Acute RHF during SARS-CoV-2 infection could be related to a convergent widespread systemic inflammatory response. Thanks to its anti-inflammatory and anti-remodeling properties, levosimendan might represent a viable therapy in this clinical setting, contributing to the dampening of the inflammatory response.

The potential impact of acute coronary syndromes on automatic sensing system in Subcutaneous-ICDs.

BACKGROUND: The Subcutaneous-ICD (S-ICD) is emerging as a suitable option for most ICD candidates, however some open issues regarding the sensing algorithm still remain. OBJECTIVES: We aimed to examine the performance of the S-ICD sensing algorithm in patients hospitalized for ST elevation myocardial infarction (STEMI), non ST elevation acute coronary syndrome (NSTE-ACS) or chronic coronary syndrome (CCS), before and after revascularization. METHODS: We performed a S-ICD automated screening on 75 patients, 21 hospitalized for STEMI, 23 for NSTE-ACS and 31 for CCS, before and after percutaneous revascularization, regardless their eligibility to ICD implantation. RESULTS: Patients did not differ in clinical, electrocardiographic and echocardiographic parameters. Rates of screening pass were significantly lower in STEMI patients compared to NSTE-ACS and CCS (5% vs 56.7% vs 81% respectively, p < .0001). The viability of the primary vector was lower in STEMI patients compared to NSTE-ACS and CCS (33% vs 56% vs 71%, p .027 respectively). After revascularization, there were no more significant differences between groups. Pairing subjects at baseline and after revascularization, STEMI subjects percentages of screening success were respectively 5% and 81% (p < .001) and the rates of primary vector viability were 33% and 81% (p .002). STEMI was the only independent predictor of screening failure at multivariate logistic regression analysis (odds ratio 10.68 confidence interval 2.77-41.38, p = .001). CONCLUSION: The performance of the S-ICD and possible malfunction detections in the context of an acute ischemic event deserve further evaluation. Adequate patient selection and the development of dynamic device programming are warranted.

Identification of the TCL1/MTCP1-like 1 (TML1) gene from the region next to the TCL1 locus.

The region on chromosome 14q32.1 is frequently involved in chromosomal translocations and inversions with one of the T-cell receptor loci in human T-cell leukemias and lymphomas. The breakpoints of the different rearrangements segregate into two clusters: inversion on the centromeric side and simple balanced translocations on the telomeric side. If the target gene activated by these different types of chromosomal rearrangements is the same, the gene must reside between the two clusters of breakpoints in a region of approximately 160 kb. By screening of a placenta cDNA library using genomic probes derived from the vicinity of TCL1 locus, we have identified a gene coding for a 1.7-kb transcript that is expressed in leukemic cells carrying a t(14;14)(q11;q32) chromosome translocation. The cognate cDNA sequence reveals an open reading frame of 384 nucleotides encoding a Mr 15,000 protein with approximately 30% of homology with both p14TCL1 and p13MTCP1 oncoproteins. The genomic organization of the TML1 locus was characterized, with three exons located 15 kb from and tail-to-tail in relation to TCL1 locus. Because of its location and sequence similarity with TCL1 and MTCP1 oncoproteins, this gene, named TML1 (TCL1/MTCP1-like 1) is a candidate gene that is potentially involved in leukemogenesis.

Characterization and localization of the TCL-1 oncogene product.

The TCL-1 gene maps at chromosome 14q32.1 and is activated in T cell leukemias and lymphomas by either chromosome translocations or inversions that juxtapose the TCL-1 gene to the alpha/delta or the beta locus of the T cell receptor. The open reading frame of the TCL-1 gene, coding for a protein of 114 amino acids, was expressed in bacteria and antisera were raised against it. The antibodies recognized the predicted TCL-1 M(r) 14,000 protein product in cells expressing TCL-1 mRNA. Cell fractionation experiments indicated that the TCL-1 protein is present in the microsomal fraction. These results were confirmed by confocal microscopy. The TCL-1 protein has considerable sequence similarities to the product of the MTCP-1 gene on chromosome Xq28, which is involved in T cell lympho-proliferative diseases. Thus, TCL-1 may represent a member of a novel family of genes involved in lymphoid proliferation and/or survival and in T cell malignancies.

Regulation of TCL1 expression in B- and T-cell lymphomas and reactive lymphoid tissues.

Chromosomal rearrangements observed in T-cell prolymphocytic leukemia involve the translocation of one T-cell receptor gene to either chromosome 14q32 or Xq28, deregulating the expression of cellular protooncogenes of unknown function, such as TCL1 or its homologue, MTCP1. In the human hematopoietic system, TCL1 expression is predominantly observed in developing B lymphocytes, whereas its overexpression in T cells causes mature T-cell proliferation in transgenic mice. In this study, using a newly generated monoclonal antibody against recombinant TCL1 protein, we extended our analysis mainly by immunohistochemistry and also by fluorescence-activated cell sorting and Western blot to a large tumor lymphoma data bank including 194 cases of lymphoproliferative disorders of B- and T-cell origin as well as reactive lymphoid tissues. The results obtained show that in reactive lymphoid tissues, TCL1 is strongly expressed by a subset of mantle zone B lymphocytes and is expressed to a lesser extent by follicle center cells and by scattered interfollicular small lymphocytes. In B-cell neoplasia, TCL1 was expressed in the majority of the cases, including lymphoblastic lymphoma, chronic lymphocytic leukemia, mantle cell lymphoma, follicular lymphoma, Burkitt lymphoma, diffuse large B-cell lymphoma (60%), and primary cutaneous B cell lymphoma (55%). TCL1 expression was observed in both the cytoplasmic and nuclear compartments, as confirmed by Western blot analysis. Conversely, TCL1 was not expressed in Hodgkin/Reed-Sternberg cells, multiple myelomas, marginal zone B-cell lymphomas, CD30+ anaplastic large cell lymphoma, lymphoblastic T-cell lymphoma, peripheral T-cell lymphoma, and mycosis fungoides. These data indicate that TCL1 is expressed in more differentiated B cells, under both reactive and neoplastic conditions, from antigen committed B cells and in germinal center B cells and is down-regulated in the latest stage of B-cell differentiation.

TCL1 is overexpressed in patients affected by adult T-cell leukemias.

Among mature postthymic T-cell leukemias, adult T-cell leukemia (ATL) has characteristic clinicopathological entities. The association with the human T-cell leukemia/lymphotropic virus type I is one of the distinctive etiopathogenetic features of this disease. However, unlike other acute transforming retroviruses, the human T-cell leukemia/lymphotropic virus type I lacks an oncogene within its genome. Other human postthymic leukemias, such as T-prolymphocytic leukemias, involve mostly the CD4 cellular subset and share many similarities to ATLs (aggressive course, cutaneous involvement, CD4+, CD29+, CD45RA- phenotype, and alpha-naphthyl-acetate esterase positivity). A chromosomal rearrangement at 14q32.1, involved in translocations or inversions with either the alpha/delta locus [t(14;14)(q11;q32.1), inv14(q11;q32.1)], or the beta-chain locus of the T-cell receptor [t(7;14)(q35;q32.1)] is found. These rearrangements disregulate a gene, TCL1, located at the 14q32.1 region, that we show is physiologically expressed in CD4/CD8 double-negative thymocyte cells, but not in more differentiated CD4+ and CD8+ subpopulations. Here, using molecular and immunocytochemical analysis, we report that TCL1 is also overexpressed in 10 of 10 ATL specimens, indicating that this gene may play an important role in the pathogenesis of this disease.

TCL1 transgenic mouse model as a tool for the study of therapeutic targets and microenvironment in human B-cell chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is a B-cell malignancy with a mature phenotype. In spite of its relatively indolent nature, no radical cure is as yet available. CLL is not associated with either a unique cytogenetic or a molecular defect, which might have been a potential therapeutic target. Instead, several factors are involved in disease development, such as environmental signals which interact with genetic abnormalities to promote survival, proliferation and an immune surveillance escape. Among these, PI3-Kinase signal pathway alterations are nowadays considered to be clearly important. The TCL1 gene, an AKT co-activator, is the cause of a mature T-cell leukemia, as well as being highly expressed in all B-CLL. A TCL1 transgenic mouse which reproduces leukemia with a distinct immunophenotype and similar to the course of the human B-CLL was developed several years ago and is widely used by many groups. This is a review of the CLL biology arising from work of many independent investigators who have used TCL1 transgenic mouse model focusing on pathogenetic, microenviroment and therapeutic targets.

The murine Tcl1 oncogene: embryonic and lymphoid cell expression.

In human leukemias and lymphomas nonrandom chromosomal rearrangements cause changes in cell growth and/or survival in such a way as to promote malignancy. The detailed study of the biochemical and genetic pathways altered in human cancer requires the identification or development of models to allow the study and manipulation of cancer gene function. Recently, the breakpoint gene TCL1, involved in chromosome translocations observed mostly in mature T-cell proliferations and chronic lymphocytic leukemias (CLL), was isolated and characterized, and showed to be part of a new gene family of proteins involved in these tumors. The murine Tcl1 gene, is similar in sequence to the murine and human MTCP1 gene also involved in T cell leukemias. The murine Tcl1 gene was shown to reside on mouse chromosome 12 in a region syntenic to human chromosome 14. Furthermore, we show that the murine Tcl1 gene is expressed early in mouse embryonic development and demonstrates expression in fetal hematopoietic organs as well as in immature T and B cells. Characterization of the murine Tcl1 gene will help in developing a mouse model of CLL and would provide the best opportunity to study and decipher the role of TCL1 in malignant transformation.

Acquired chromosome 11q deletion involving the ataxia teleangiectasia locus in B-cell non-Hodgkin's lymphoma: correlation with clinicobiologic features.

PURPOSE: To study the clinicobiologic significance of acquired 11q deletions involving the ataxia teleangiectasia locus (ATM+/-) in B-cell non-Hodgkin's lymphomas (NHL). PATIENTS AND METHODS: Fifty-three indolent lymphomas and 82 aggressive lymphomas were studied by conventional cytogenetic analysis and by fluorescence in situ hybridization using an 11q22-23 probe recognizing ATM sequences. Pertinent clinical data were collected. RESULTS: A hemizygous ATM deletion was seen in 44% to 88% of the interphase cells in 15 cases (11.1%); four patients had an indolent lymphoma (follicular center cell lymphoma), and 11 patients had an aggressive lymphoma (five mantle-cell lymphomas [MCLs] and six diffuse large-cell lymphomas). Dual-color hybridization studies showed ATM deletion to be possibly a secondary aberration in three patients with MCL. Ten out of 15 ATM+/- patients had a complex karyotype, 11 out of 15 had more than 90% abnormal metaphases (AA karyotype status), and +12, 13q14 deletion, and 17p13 deletion were seen in seven, four, and five cases, respectively. Patients with ATM+/- more frequently had a complex karyotype (P =.01) and the AA karyotype (P =.04) compared with patients without ATM+/-. With the exception of a poor performance status (P =.001), no correlation was found between ATM+/-, initial clinical variables, and complete remission rate; whereas a highly significant association was found with shorter survival (P <.0001). This cytogenetic lesion maintained its prognostic importance in multivariate analysis (P =.0004), along with performance status (P =.0006), serum lactate dehydrogenase level (P =.03), splenomegaly (P =.01), and histologic grade (P =.03). When analyzing indolent lymphomas and aggressive lymphomas separately, ATM+/- maintained its prognostic importance as an independent variable in both histologic groups (P =.0001 and P =.016, respectively). CONCLUSION: Though possibly not representing a primary genetic lesion in the majority of cases, the acquired ATM+/- status has clinicobiologic importance in NHL, possibly representing a major cytogenetic determinant of outcome.

miR-181b as a therapeutic agent for chronic lymphocytic leukemia in the Eµ-TCL1 mouse model.

The involvement of microRNAs (miRNAs) in chronic lymphocytic leukemia (CLL) pathogenesis suggests the possibility of anti-CLL therapeutic approaches based on miRNAs. Here, we used the Eµ-TCL1 transgenic mouse model, which reproduces leukemia with a similar course and distinct immunophenotype as human B-CLL, to test miR-181b as a therapeutic agent.In vitro enforced expression of miR-181b mimics induced significant apoptotic effects in human B-cell lines (RAJI, EHEB), as well as in mouse Eµ-TCL1 leukemic splenocytes. Molecular analyses revealed that miR-181b not only affected the expression of TCL1, Bcl2 and Mcl1 anti-apoptotic proteins, but also reduced the levels of Akt and phospho-Erk1/2. Notably, a siRNA anti-TCL1 could similarly down-modulate TCL1, but exhibited a reduced or absent activity in other relevant proteins, as well as a reduced effect on cell apoptosis and viability. In vivo studies demonstrated the capability of miR-181b to reduce leukemic cell expansion and to increase survival of treated mice.These data indicate that miR-181b exerts a broad range of actions, affecting proliferative, survival and apoptotic pathways, both in mice and human cells, and can potentially be used to reduce expansion of B-CLL leukemic cells.

Skewed expression of activation, differentiation and homing-related antigens in circulating cells from patients with cutaneous T cell lymphoma associated with CD7- T helper lymphocytes expansion.

Mycosis fungoides and Sézary syndrome represent the most frequent forms of cutaneous T cell lymphoma. Both are characterized by skin infiltrating and/or circulating malignant cells displaying a CD4+CD7- phenotype in the majority of cases. Because an expansion of CD4+CD7- cells may also be found in inflammatory dermatoses or in the aging process, we evaluated, by flow cytometry, the relationship between CD7 expression and the distribution of differentiation/activation or homing antigens on peripheral blood lymphocytes from 36 cutaneous T cell lymphoma patients and from healthy donors. CD4+CD7- cells were increased in all patients with cutaneous T cell lymphoma. As a consequence, the CD7+/- ratio was reduced in stage I-II mycosis fungoides (3.96 vs 6.55 in healthy donors), and inverted in stage III-IV MF and Sézary syndrome (0.28 and 0.12 respectively). In the late stage of disease, the CD7+/- inverted ratio was strictly related to the expression of CD15s, CD60, and CD45R0, and the lack of expression of CD26 and CD49d. Interestingly, in leukemic patients, this phenotype was also associated with peculiar morphologic (large size) or phenotypical (CD3dim expression) characteristics. Furthermore, a progressive reduction of circulating CD8+ cells was also seen throughout all stages of disease. The presence of these populations in cutaneous T cell lymphoma at late phases of disease and Sézary syndrome suggests that all of these molecules may play an important part in the activation pathway and skin homing of circulating T cells in lymphoproliferative disorders. Therefore, this may constitute a distinctive feature in cutaneous T cell lymphoma patients with more aggressive characteristics.

Orphan receptor hepatocyte nuclear factor-4 antagonizes estrogen receptor alpha-mediated induction of human coagulation factor XII gene.

Factor XII (FXII) is a liver-specific zymogen involved in the regulation of hemostasis, particularly in the activation of fibrinolysis. Transcription of the FXII gene is stimulated by estrogens through specific interaction of the estrogen receptor alpha (ER alpha) with an estrogen response element present on FXII promoter. Interestingly, the magnitude of ER alpha induction in liver HepG2 cells is much lower than in NIH3T3 fibroblasts, suggesting that cell-specific factors may modulate ER alpha-dependent trans-activation. Comparative footprinting analysis of FXII promoter (from nucleotides -181 to +49) in liver vs. non-liver cell environments allowed identification of four deoxyribonuclease I-protected sites only in the presence of HepG2 nuclear extracts. Computerized homology search identified sites III and IV as consensus binding sequences for the liver-enriched transcription factor hepatocyte nuclear factor-4 (HNF-4), formerly an orphan receptor belonging to the superfamily of steroid/thyroid hormone nuclear receptors. In transient transfection assays in NIH3T3 cells, HNF-4 significantly inhibited (70%) estrogen induction of FXII promoter while not affecting basal promoter activity. Conversely, HNF-4 did not inhibit estrogen inducibility of FXII promoter in HepG2 cells due to the high endogenous levels of HNF-4 protein. In gel shift assays, HNF-4, either present in HepG2 nuclear extracts or generated by in vitro transcription/translation, specifically bound FXII promoter. This interaction is strictly required in eliciting the antagonistic effect because in NIH3T3 cells, selective mutations of sites III and IV abrogated HNF-4 inhibitory properties. In the liver-specific environment, the same mutant construct exhibited higher estrogen-dependent inducibility compared with native promoter. Rescue of estrogen responsiveness was also achieved using a dominant negative HNF-4, which counteracted endogenous HNF-4 activity. In conclusion, our findings address a direct role for HNF-4 in modulating estrogen-dependent transcription of the FXII gene promoter.

Inhibition of ERalpha-mediated trans-activation of human coagulation factor XII gene by heteromeric transcription factor NF-Y.

Human coagulation factor XII promoter contains an estrogen response element that mediates ligand-activated ERalpha induction of coagulation factor XII gene expression. The 3'-half of coagulation factor XII-estrogen response element overlaps a putative CCAAT box, the widespread regulatory element specifically recognized by the heteromeric transcription factor NF-Y. Transient cotransfection of NF-Y and ERalpha results in strong inhibition of estrogen stimulation of coagulation factor XII promoter activity. NF-Y antagonism is primarily exerted by the NF-YA subunit and does not require binding to the CCAAT element, as NF-YA mutants with impaired DNA binding capacity retain the ability to inhibit ERalpha trans-activation. EMSAs with increasing concentrations of recombinant NF-Y do not detect the formation of NF-Y-DNA complexes or show impairment of ERalpha binding to estrogen response element. Immunoprecipitation of whole cell extracts with anti-ERalpha antibody reveals an in vivo association between the two transcription factors, which is abolished by deletion of the NF-YA carboxyl-terminus. In functional experiments with sequential NF-YA deletion mutants the HAP2-homology region appears essential in eliciting NF-YA antagonistic activity. In conclusion, our results demonstrate that heteromeric transcription factor NF-Y inhibits estrogen induction of coagulation factor XII promoter in a DNA binding-independent fashion and suggest a novel role for NF-Y as a partner for the ERalpha transcription complex.

Effects of exogenous p53 transduction in thyroid tumor cells with different p53 status.

Recovery of p53 function in undifferentiated thyroid carcinoma cells carrying an altered p53 gene is able to modify cell tumorigenic properties. It is not known whether such an effect may also be achieved in thyroid cancer cells expressing wild-type p53, as in the majority of differentiated thyroid carcinomas. Effects of p53 transduction in a thyroid carcinoma cell line (FRO) exhibiting a wild-type endogenous p53 gene, in comparison to a cell line (WRO) exhibiting mutant p53, were investigated by using an inducible chimeric construct containing human p53 complementary DNA fused to the ligand binding domain of the estrogen receptor (p53ER). FRO cells were unaffected by exogenous p53 expression in terms of both proliferation and viability. On the contrary, p53 reexpression in WRO cells containing hemizygous mutated p53 allele caused a strong growth inhibition due to cell accumulation in the G1 phase of the cell cycle. In addition, exogenous p53 did not influence FRO cell behavior in response to TSH treatment or modify cell resistance to the chemotherapeutic agent, doxorubicin. Our results indicate that exogenous expression of wild-type p53 affects thyroid tumorigenic properties only in cells carrying an altered p53, whereas it is ineffective in cells expressing wild-type p53 activity. Therefore, the endogenous p53 status seems to be a major determinant for the effectiveness of a p53-based gene therapy for thyroid cancer.

MicroRNA profiling reveals that miR-21, miR486 and miR-214 are upregulated and involved in cell survival in Sézary syndrome.

Sézary syndrome (SS) is an incurable leukemic variant of cutaneous T-cell lymphoma and its pathogenesis is still unknown. Diagnosis/prognosis may strongly ameliorate the management of SS individuals. Here, we profiled the expression of 470 microRNAs (miRNAs) in a cohort of 22 SS patients, and we identified 45 miRNAs differentially expressed between SS and controls. Using predictive analysis, a list of 19 miRNAs, including miR-21, miR-214, miR-486, miR-18a, miR-342, miR-31 and let-7 members were also found. Moreover, we defined a signature of 14 miRNAs including again miR-21, potentially able to discriminate patients with unfavorable and favorable outcome. We validated our data for miR-21, miR-214 and miR-486 by qRT-PCR, including an additional set of array-independent SS cases. In addition, we also provide an in vitro evidence for a contribution of miR-214, miR-486 and miR-21 to apoptotic resistance of CTCL cell line.

The Tcl1 oncogene defines secondary hair germ cells differentiation at catagen-telogen transition and affects stem-cell marker CD34 expression.

Overexpression of the TCL1 gene family plays a role in the onset of T-cell leukemias in mice and in humans. The Tcl1 gene is tightly regulated during early embryogenesis in which it participates in embryonic stem (ES)-cells proliferation and during lymphoid differentiation. Here, we provide evidences that Tcl1 is also important in mouse hair follicle (HF) and skin homeostasis. We found that Tcl1(-/-) adult mice exhibit hair loss, leading to alopecia with extensive skin lesions. By analysing Tcl1 expression in the wild-type (wt) skin through different stages of hair differentiation, we observe high levels in the secondary hair germ (HG) cells and hair bulges, during early anagen and catagen-telogen transition phases. The loss of Tcl1 does not result in apparent skin morphological defects during embryonic development and at birth, but its absence causes a reduction of proliferation in anagen HFs. Importantly, we show the that absence of Tcl1 induces a significant loss of the stem-cell marker CD34 (but not alpha6-integrin) expression in the bulge cells, which is necessary to maintain stem-cell characteristics. Therefore, our findings indicate that Tcl1 gene(s) might have important roles in hair formation, by its involvement in cycling and self-renewal of transient amplifying (TA) and stem-cell (SC) populations.

Chromosome walking on the TCL1 locus involved in T-cell neoplasia.

The TCL1 locus on chromosome 14 band q32.1 is frequently involved in the chromosomal translocations and inversions with the T-cell receptor genes observed in several T-cell tumors, including T-prolymphocytic leukemias, acute and chronic leukemias associated with the immunodeficiency syndrome ataxia-telangiectasia, and adult T-cell leukemia. All breakpoints cloned in this area have been mapped to 14q32.1, an area distant approximately 10,000 kb from the immunoglobulin heavy-chain gene locus on chromosome 14q band 32.3. Except for two cases of inversion, no physical linkage of the cloned breakpoints has been reported, nor has a gene been identified in this region. Taking advantage of chromosome-walking techniques and of the P1 phage, we cloned and characterized 450 kb of the germ-line TCL1 locus, starting from the breakpoints of two independent T-cell leukemias. We show that all molecular rearrangements characterized so far map to these clones, indicating not only that this region is the target of chromosomal rearrangements occurring in this area but also that both inversion and translocations occur within a 300-kb region in the T-cell leukemias. In the attempt to identify a candidate oncogene responsible for the malignant transformation, a CpG island centromeric to the inversions and to the translocations has been identified. Two probes near the CpG island have detected sequences conserved among species, as well as two transcripts in the K562 human erythroleukemia cell line. On the basis of these data, a model of activation of the putative TCL1 oncogene is suggested.