Transcriptional Analysis of Lennert Lymphoma Reveals a Unique Profile and Identifies Novel Therapeutic Targets

Lennert lymphoma (LL) is a lymphoepithelioid morphological variant of peripheral T-cell lymphoma—not otherwise specified (PTCL/NOS), clinically characterized by better prognosis if compared with other PTCL/NOS. Although well characterized as far as morphology and phenotype are concerned, very little is known regarding its molecular features. In this study, we investigated the transcriptional profile of this tumor aiming 1) to identify its cellular counterparts; 2) to better define its relation with other PTCLs—and, therefore, its possible position in lymphoma classification; and 3) to define pathogenetic mechanisms, possibly unveiling novel therapeutic targets. To address these issues, we performed gene and microRNA expression profiling on LL and other PTCL/NOS cases; we identified different genes and microRNAs that discriminated LL from other PTCL/NOS. Particularly, LL revealed a molecular signature significantly enriched in helper function and clearly distinguishable from other PTCL/NOS. Furthermore, PI3K/Akt/mTOR pathway emerged as novel potential therapeutic target. In conclusion, based on the already known particular morphological and clinical features, the new molecular findings support the hypothesis that LL might be classified as a separate entity. Preclinical and clinical studies testing the efficacy of PI3K/MTOR inhibitors in this setting are warranted

Gene expression profile predicts response to the combination of tosedostat and low-dose cytarabine in elderly AML

Tosedostat is an orally administered metalloenzyme inhibitor with antiproliferative and antiangiogenic activity against hematological and solid human cancers. Clinical activity has been demonstrated in relapsed acutemyeloid leukemia (AML). Thirty-three elderly patients with AML (median age, 75 years) received 120mgtosedostat orally once daily combinedwith subcutaneous low-dose cytarabine (20 mg twice per day for 10 days, up to 8 cycles), until disease progression. Inductionmortality was 12%. According to an intention-to-treat analysis, the complete remission (CR) rate was 48.5%, and thus the primary end point of the study was reached (expected CR, 25%). The partial remission rate was 6.1%,with an overall response rate of 54.5%. Furthermore, 4 of 33 patients had stable disease (median: 286 days). Themedian progression-free survival and overall survival (OS)were 203 days and 222 days, respectively. Responding patients had a longer median OS than nonresponding patients (P=.001). Amicroarray analysis performed in 29 of 33 patients identified 188 genes associated with clinical response (CR vs no CR). Three of them (CD93, GORASP1, CXCL16) were validated by quantitative polymerase chain reaction, which correctly classified 83% of the patients. Specifically, CR achievement was efficiently predicted by the gene expression patterns, with an overall accuracy exceeding 90%. Finally, a negative predictive value of 100% was validated in an independent series, thus representing the first molecular predictor for clinical response to a specific combination drug treatment for AML

Contribution of the lung to the genesis of cheyne-stokes respiration in heart failure: Plant gain beyond chemoreflex gain and circulation time

Background-The contribution of the lung or the plant gain (PG; ie, change in blood gases per unit change in ventilation) to Cheyne-Stokes respiration (CSR) in heart failure has only been hypothesized by mathematical models, but never been directly evaluated.Methods and Results-Twenty patients with systolic heart failure (age, 72.4 +/- 6.4 years; left ventricular ejection fraction, 31.5 +/- 5.8%), 10 with relevant CSR (24-hour apnea-hypopnea index [AHI] >= 10 events/h) and 10 without (AHI <10 events/h) at 24-hour cardiorespiratory monitoring underwent evaluation of chemoreflex gain (CG) to hypoxia (CG(O2)) and hypercapnia (CG(CO2)) by rebreathing technique, lung-to-finger circulation time, and PG assessment through a visual system. PG test was feasible and reproducible (intraclass correlation coefficient, 0.98; 95% CI, 0.91-0.99); the best-fitting curve to express the PG was a hyperbola (R-2 >= 0.98). Patients with CSR showed increased PG, CG(CO2) (but not CG(O2)), and lung-to-finger circulation time, compared with patients without CSR (all P<0.05). PG was the only predictor of the daytime AHI (R=0.56, P=0.01) and together with the CG(CO2) also predicted the nighttime AHI (R=0.81, P=0.0003) and the 24-hour AHI (R=0.71, P=0.001). Lung-to-finger circulation time was the only predictor of CSR cycle length (R=0.82, P=0.00006).Conclusions-PG is a powerful contributor of CSR and should be evaluated together with the CG and circulation time to individualize treatments aimed at stabilizing breathing in heart failure

Oxidative stress in cerebral small vessel disease dizziness patients, basally and after polyphenol compound supplementation

Leukoaraiosis (LA) is a common radiological finding in elderly, frequently associated with several clinical disorders, including unexplained dizziness. The pathogenesis of LA is multifactorial, with a dysfunction of cerebral microcirculation resulting in chronic hypoperfusion and tissue loss, with oxidative stress involved in this cascade. The aim of this study was to analyse some oxidative stress biomarkers in a cohort of LA patients. In a subgroup of 33 patients with LA and unexplained dizziness, we have then performed an open study to evaluate if 60-day supplementation with a poliphenol compound may modify these biomarkers and influence quality of life, analysed with the Dizziness handicap Inventory (DHI) scale. At baseline, blood oxidative stress parameters values were outside normal ranges and compared to matched healthy controls. After the two months supplementation, we observed a significant decrement of advanced oxidation protein products values and a significant improvement of DHI. Oxidative stress biomarkers may be useful to detect redox imbalance in LA and to provide non-invasive tools to monitor disease status and response to therapy

Macrophage MerTK promotes profibrogenic cross-talk with hepatic stellate cells via soluble mediators

Background & Aims: Activation of Kupffer cells and recruitment of monocytes are key events in fibrogenesis. These cells release soluble mediators which induce the activation of hepatic stellate cells (HSCs), the main fibrogenic cell type within the liver. Mer tyrosine kinase (MerTK) signaling regulates multiple processes in macrophages and has been implicated in the pathogenesis of non-alcoholic steatohepatitis-related fibrosis. In this study, we explored if MerTK activation in macrophages influences the profibrogenic phenotype of HSCs. Methods: Macrophages were derived from THP-1 cells or differentiated from peripheral blood monocytes towards MerTK+/CD206+/CD163+/CD209- macrophages. The role of MerTK was assessed by pharmacologic and genetic inhibition. HSC migration was determined in Boyden chambers, viability was measured by the MTT assay, and proliferation was evaluated by the BrdU incorporation assay. Results: Gas-6 induced MerTK phosphorylation and Akt activation in macrophages, and these effects were inhibited by UNC569. During polarization, MerTK+/CD206+/CD163+/CD209- macrophages exhibited activation of STAT3, ERK1/2, p38 and increased expression of VEGF-A. Activation of MerTK in THP-1 macrophages induced a secretome which promoted a significant increase in migration, proliferation, viability and expression of profibrogenic factors in HSCs. Similarly, conditioned medium from MerTK+ macrophages induced a significant increase in cell migration, proliferation, STAT3 and p38 phosphorylation and upregulation of IL-8 expression in HSCs. Moreover, conditioned medium from Gas-6-stimulated Kupffer cells induced a significant increase in HSC proliferation. These effects were specifically related to MerTK expression and activity in macrophages, as indicated by pharmacologic inhibition and knockdown experiments. Conclusions: MerTK activation in macrophages modifies the secretome to promote profibrogenic features in HSCs, implicating this receptor in the pathogenesis of hepatic fibrosis. Lay summary: Fibrosis represents the process of scarring occurring in patients with chronic liver diseases. This process depends on production of scar tissue components by a specific cell type, named hepatic stellate cells, and is regulated by interaction with other cells. Herein, we show that activation of MerTK, a receptor present in a population of macrophages, causes the production of factors that act on hepatic stellate cells, increasing their ability to produce scar tissue

Burkitt lymphoma beyond MYC translocation: N-MYC and DNA methyltransferases dysregulation

Background: The oncogenic transcription factor MYC is pathologically activated in many human malignancies. A paradigm for MYC dysregulation is offered by Burkitt lymphoma, where chromosomal translocations leading to Immunoglobulin gene-MYC fusion are the crucial initiating oncogenic events. However, Burkitt lymphoma cases with no detectable MYC rearrangement but maintaining MYC expression have been identified and alternative mechanisms can be involved in MYC dysregulation in these cases. Methods: We studied the microRNA profile of MYC translocation-positive and MYC translocation-negative Burkitt lymphoma cases in order to uncover possible differences at the molecular level. Data was validated at the mRNA and protein level by quantitative Real-Time polymerase chain reaction and immunohistochemistry, respectively. Results: We identified four microRNAs differentially expressed between the two groups. The impact of these microRNAs on the expression of selected genes was then investigated. Interestingly, in MYC translocation-negative cases we found over-expression of DNA-methyl transferase family members, consistent to hypo-expression of the hsa-miR-29 family. This finding suggests an alternative way for the activation of lymphomagenesis in these cases, based on global changes in methylation landscape, aberrant DNA hypermethylation, lack of epigenetic control on transcription of targeted genes, and increase of genomic instability. In addition, we observed an over-expression of another MYC family gene member, MYCN that may therefore represent a cooperating mechanism of MYC in driving the malignant transformation in those cases lacking an identifiable MYC translocation but expressing the gene at the mRNA and protein levels. Conclusions: Collectively, our results showed that MYC translocation-positive and MYC translocation-negative Burkitt lymphoma cases are slightly different in terms of microRNA and gene expression. MYC translocation-negative Burkitt lymphoma, similarly to other aggressive B-cell non Hodgkin's lymphomas, may represent a model to understand the intricate molecular pathway responsible for MYC dysregulation in cancer

Constitutive psgl-1 correlates with cd30 and tcr pathways and represents a potential target for immunotherapy in anaplastic large t-cell lymphoma

Due to the high expression of P-selectin glycoprotein ligand-1 (PSGL-1) in lymphoprolif-erative disorders and in multiple myeloma, it has been considered as a potential target for humoral immunotherapy, as well as an immune checkpoint inhibitor in T-cells. By investigating the expression of SELPLG in 678 T-and B-cell samples by gene expression profiling (GEP), further supported by tissue microarray and immunohistochemical analysis, we identified anaplastic large T-cell lymphoma (ALCL) as constitutively expressing SELPLG at high levels. Moreover, GEP analysis in CD30+ ALCLs highlighted a positive correlation of SELPLG with TNFRSF8 (CD30-coding gene) and T-cell receptor (TCR)-signaling genes (LCK, LAT, SYK and JUN), suggesting that the common dysreg-ulation of TCR expression in ALCLs may be bypassed by the involvement of PSGL-1 in T-cell activation and survival. Finally, we evaluated the effects elicited by in vitro treatment with two anti-PSGL-1 antibodies (KPL-1 and TB5) on the activation of the complement system and induction of apoptosis in human ALCL cell lines. In conclusion, our data demonstrated that PSGL-1 is specifically enriched in ALCLs, altering cell motility and viability due to its involvement in CD30 and TCR signaling, and it might be considered as a promising candidate for novel immunotherapeutic approaches in ALCLs