Inhibition of bromodomain and extra-terminal proteins increases sensitivity to venetoclax in chronic lymphocytic leukaemia.

The development of drugs able to target BTK, PI3k-delta and BCL2 has dramatically improved chronic lymphocytic leukaemia (CLL) therapies. However, drug resistance to these therapies has already been reported due to non-recurrent changes in oncogenic pathways and genes expression signatures. In this study, we investigated the cooperative role of the BCL2 inhibitor venetoclax and the BRD4 inhibitor JQ1. In particular, we found that JQ1 shows additional activity with venetoclax, in CLL cell lines and in ex vivo isolated primary CD19+ lymphocytes, arguing in favour of combination strategies. Lastly, JQ1 is also effective in venetoclax-resistant CLL cell lines. Together, our findings indicated that the BET inhibitor JQ1 could be a promising therapy in CLL, both as first-line therapy in combination with venetoclax and as second-line therapy, after the emergence of venetoclax-resistant clones.

Platelet function and activation markers in primary hypercholesterolemia treated with anti-PCSK9 monoclonal antibody: A 12-month follow-up.

BACKGROUND AND AIMS: In the association between hypercholesterolemia (HC) and thrombotic risk platelet hyper-reactivity plays an important role. The inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) to reduce plasma LDL-cholesterol merges as effective therapeutic strategy to prevent cardiovascular (CV) events. Aim of this study was to verify whether a treatment up to 12 months with the monoclonal antibodies (mAbs) anti-PCSK9 influences platelet function in primary HC. METHODS AND RESULTS: In patients affected by primary HC (n = 24), all on background of statin and 17 on acetyl salicylic acid (ASA), platelet function parameters were evaluated at baseline up to 12 months of treatment with the mAb anti-PCSK9 alirocumab or evolocumab. From baseline, the treatment with anti-PCSK9 mAbs: i) in ASA HC patients, significantly decreased platelet aggregation detected in platelet-rich plasma by light transmission aggregometry and in whole blood Platelet Function Analyzer-100 assay; ii) in all HC patients, significantly decreased platelet membrane expression of CD62P and plasma levels of the in vivo platelet activation markers soluble CD40 Ligand, Platelet Factor-4, and soluble P-Selectin. Furthermore, CD62P expression, and sP-Selectin, PF-4, sCD40L levels significantly correlated with serum PCSK9. CONCLUSION: Besides markedly lowering LDL-c levels, our results suggest that HC patients benefit from anti-PCSK9 mAb treatment also for reducing platelet reactivity and increasing platelet sensitivity to the inhibitory effects of aspirin. These effects on platelets could play a role in the reduction of CV event incidence in patients treated with PCSK9 inhibitors.

Association between High On-Aspirin Platelet Reactivity and Reduced Superoxide Dismutase Activity in Patients Affected by Type 2 Diabetes Mellitus or Primary Hypercholesterolemia.

Platelet hyperactivation is involved in the established prothrombotic condition of metabolic diseases such as Type 2 Diabetes Mellitus (T2DM) and familial hypercholesterolemia (HC), justifying the therapy with aspirin, a suppressor of thromboxane synthesis through the irreversible inhibition of cyclooxygenase-1 (COX-1), to prevent cardiovascular diseases. However, some patients on aspirin show a higher than expected platelet reactivity due, at least in part, to a pro-oxidant milieu. The aim of this study was to investigate platelet reactivity in T2DM (n = 103) or HC (n = 61) patients (aspirin, 100 mg/day) and its correlation with biomarkers of redox function including the superoxide anion scavenger superoxide dismutase (SOD) and the in vivo marker of oxidative stress urinary 8-iso-prostaglandin F2α. As results, in T2DM and HC subjects the prevalence of high on-aspirin platelet reactivity was comparable when both non-COX-1-dependent and COX-1-dependent assays were performed, and platelet reactivity is associated with a lower SOD activity that in a stepwise linear regression appears as the only predictor of platelet reactivity. To conclude, in T2DM and HC, similarly, the impairment of redox equilibrium associated with a decrease of SOD activity could contribute to a suboptimal response to aspirin.

The non-genomic loss of function of tumor suppressors: an essential role in the pathogenesis of chronic myeloid leukemia chronic phase.

BACKGROUND: Chronic Myeloid Leukemia was always referred as a unique cancer due to the apparent independence from tumor suppressors' deletions/mutations in the early stages of the disease. However, it is now well documented that even genetically wild-type tumor suppressors can be involved in tumorigenesis, when functionally inactivated. In particular, tumor suppressors' functions can be impaired by subtle variations of protein levels, changes in cellular compartmentalization and post-transcriptional/post-translational modifications, such as phosphorylation, acetylation, ubiquitination and sumoylation. Notably, tumor suppressors inactivation offers challenging therapeutic opportunities. The reactivation of an inactive and genetically wild-type tumor suppressor could indeed promote selective apoptosis of cancer cells without affecting normal cells. MAIN BODY: Chronic Myeloid Leukemia (CML) could be considered as the paradigm for non-genomic loss of function of tumor suppressors due to the ability of BCR-ABL to directly promote functionally inactivation of several tumor suppressors. SHORT CONCLUSION: In this review we will describe new insights on the role of FoxO, PP2A, p27, BLK, PTEN and other tumor suppressors in CML pathogenesis. Finally, we will describe strategies to promote tumor suppressors reactivation in CML.

Mechanisms of p53 Functional De-Regulation: Role of the IκB-α/p53 Complex.

TP53 is one of the most frequently-mutated and deleted tumor suppressors in cancer, with a dramatic correlation with dismal prognoses. In addition to genetic inactivation, the p53 protein can be functionally inactivated in cancer, through post-transductional modifications, changes in cellular compartmentalization, and interactions with other proteins. Here, we review the mechanisms of p53 functional inactivation, with a particular emphasis on the interaction between p53 and IκB-α, the NFKBIA gene product.

HAUSP compartmentalization in chronic myeloid leukemia.

INTRODUCTION: PTEN plays an essential role in the pathogenesis of chronic myeloid leukemia. Recently, we have shown that BCR-ABL promotes PTEN nuclear exclusion, through the modulation of HAUSP activity. OBJECTIVES: Here, we investigate HAUSP cellular compartmentalization in primary CML samples. RESULTS: While in normal CD34 positive cells HAUSP is expressed mostly in the nucleus, in CML CD34 cells HAUSP is expressed both in the nuclear bodies and in the cytoplasm. CONCLUSIONS: This observation suggests that HAUSP behaves as a shuttling protein in CML. It can bind to BCR-ABL in the cytosol, where it is phosphorylated on tyrosine residues, and it maintains the proper compartmentalization in the nuclear bodies, where it acts as part of a PML network to regulate PTEN de-ubiquitination.

A Rare Case of Hodgkin Lymphoma of the Maxillary Sinus.

Hodgkin lymphoma (HL) is an uncommon B-cell malignant disease. It usually presents with mediastinal and/or laterocervical lymph node localization, while primary extranodal HL is a rare entity giving rise to diagnostic and therapeutic challenges. It rarely presents as just extranodal localization, so its presence within the maxillary sinus without any lymphadenopathy is exceptional. Given the rarity of this localization, there is no standard treatment for maxillary sinus HL. We present a case of a patient with extranodal HL of the right maxillary sinus treated with primary surgery followed by adjuvant sequential chemoradiation therapy.

IκBα targeting promotes oxidative stress-dependent cell death.

BACKGROUND: Oxidative stress is a hallmark of many cancers. The increment in reactive oxygen species (ROS), resulting from an increased mitochondrial respiration, is the major cause of oxidative stress. Cell fate is known to be intricately linked to the amount of ROS produced. The direct generation of ROS is also one of the mechanisms exploited by common anticancer therapies, such as chemotherapy. METHODS: We assessed the role of NFKBIA with various approaches, including in silico analyses, RNA-silencing and xenotransplantation. Western blot analyses, immunohistochemistry and RT-qPCR were used to detect the expression of specific proteins and genes. Immunoprecipitation and pull-down experiments were used to evaluate protein-protein interactions. RESULTS: Here, by using an in silico approach, following the identification of NFKBIA (the gene encoding IκBα) amplification in various cancers, we described an inverse correlation between IκBα, oxidative metabolism, and ROS production in lung cancer. Furthermore, we showed that novel IκBα targeting compounds combined with cisplatin treatment promote an increase in ROS beyond the tolerated threshold, thus causing death by oxytosis. CONCLUSIONS: NFKBIA amplification and IκBα overexpression identify a unique cancer subtype associated with specific expression profile and metabolic signatures. Through p65-NFKB regulation, IκBα overexpression favors metabolic rewiring of cancer cells and distinct susceptibility to cisplatin. Lastly, we have developed a novel approach to disrupt IκBα/p65 interaction, restoring p65-mediated apoptotic responses to cisplatin due to mitochondria deregulation and ROS-production.

The Challenge of Hemorrhagic Shock Management During Low-Molecular-Weight Heparin Treatment.

The reversal of low-molecular-weight heparin (LMWH) and the management of bleeding patients on LMWH remain highly challenging. Even if LMWH is very extensively administered in the prophylaxis and treatment of venous thrombosis, specific antidotes are lacking, and reversal strategies have very weak grade of evidences on clinical effectiveness. We here describe a reversal strategy with protamine and FVIIa in a patient presenting with hemorrhagic shock and cardiocirculatory arrest.

Nuclear-cytoplasmic Shuttling in Chronic Myeloid Leukemia: Implications in Leukemia Maintenance and Therapy.

Nuclear-cytoplasmic shuttling is a highly regulated and complex process, which involves both proteins and nucleic acids. Changes in cellular compartmentalization of various proteins, including oncogenes and tumor suppressors, affect cellular behavior, promoting or inhibiting proliferation, apoptosis and sensitivity to therapies. In this review, we will recapitulate the role of various shuttling components in Chronic Myeloid Leukemia and we will provide insights on the potential role of shuttling proteins as therapeutic targets.

Transferrin Saturation Inversely Correlates with Platelet Function.

BACKGROUND: The association between iron overload (IO) and risk of cardiovascular disease is controversial. Epidemiological studies have found a significant negative association of transferrin (Tf) saturation and cardiovascular events suggesting that higher body iron possibly confer a protective effect towards developing cardiovascular events. The biological mechanisms of this phenomenon are unknown. OBJECTIVE: This article investigates the role of IO on platelet reactivity. MATERIALS AND METHODS: This study was a prospective case-control study comparing 45 patients with IO, mostly characterized by the HFE gene mutations C282Y and/or H63D, with 32 healthy controls. We evaluated: (1) platelet aggregation in both platelet-rich plasma and whole blood, (2) platelet membrane expression of the activation marker CD62P, (3) activation of platelet signalling phosphoinositide 3-kinase /Akt and mitogen-activated protein kinase/extracellular signal-regulated kinases (Erk)-1/2 pathways, (4) a pattern of in vivo platelet activation markers, and (5) iron biomarker predictors of platelet reactivity. RESULTS: IO patients had significantly lower platelet aggregability, expression of CD62P and phosphorylation amounts of pAkt and pErk-2 in response to agonists. Furthermore, patients with higher Tf saturation levels were characterized by lower circulating levels of sCD40L, PDGF-BB and thromboxane B2. Platelet aggregation and activation parameters inversely correlated with Tf saturation and the stepwise multivariate regression analysis underlined the role of Tf saturation in predicting platelet reactivity. We also found that in vitro platelet exposure to diferric Tf, but not to iron-depleted TF, dose-dependently inhibited platelet function in all investigated subjects. CONCLUSION: Tf saturation is inversely associated with platelet reactivity and this could explain, at least in part, the association of high Tf and lower risk of cardiovascular diseases in IO.

Rhino-Orbital-Cerebral Mucormycosis after Allogeneic Hematopoietic Stem Cell Transplantation and Isavuconazole Therapeutic Drug Monitoring during Intestinal Graft versus Host Disease.

A diagnosis of rhino-orbital-cerebral mucormycosis was made in a 59-year-old man with a secondary acute myeloid leukemia a few days after hematopoietic stem cell transplantation. Prompt treatment with combined antifungal therapy (liposomal amphotericin B and isavuconazole) followed by a procedure of endoscopic sinus surgery resulted in the resolution of the infection. Therapeutic drug monitoring of isavuconazole was performed during the year of treatment showing an increment of plasma concentrations in correspondence with the improvement of intestinal GvHD, thus suggesting that in this or similar conditions TDM for isavuconazole can be of value. A literature review of cases of rhino-orbital-cerebral and rhino-cerebral mucormycosis in allogeneic hematopoietic stem cell transplant recipients was carried out.

IκB-α: At the crossroad between oncogenic and tumor-suppressive signals.

Nuclear factor κB (NF-κB) is an essential component of tumorigenesis and resistance to cancer treatments. NFKB inhibitor α (IκB-α) acts as a negative regulator of the classical NF-κB pathway through its ability to maintain the presence of NF-κB in the cytoplasm. However, IκB-α is also able to form a complex with tumor protein p53, promoting its inactivation. Recently, we demonstrated that IκB-α is able to mediate p53 nuclear exclusion and inactivation in chronic myeloid leukemia, indicating that IκB-α can modulate either oncogenic or tumor-suppressive functions, with important implications for cancer treatment. The present review describes the role of IκB-α in cancer pathogenesis, with particular attention to hematological cancers, and highlights the involvement of IκB-α in the regulation of p53 tumor-suppressive functions.

Glucagon-like peptide 1-related peptides increase nitric oxide effects to reduce platelet activation.

Glucagon-like peptide 1 (GLP-1) is object of intensive investigation for not only its metabolic effects but also the protective vascular actions. Since platelets exert a primary role in the pathogenesis of atherosclerosis, inflammation and vascular complications, we investigated whether GLP-1 directly influences platelet reactivity. For this purpose, in platelets from 72 healthy volunteers we evaluated GLP-1 receptor (GLP-1R) expression and the effects of a 15-minute incubation with the native form GLP-1(7-36), the N-terminally truncated form GLP-1(9-36) and the GLP-1 analogue Liraglutide (100 nmol/l) on: i) aggregation induced by collagen or arachidonic acid (AA); ii) platelet function under shear stress; iii) cGMP and cAMP synthesis and cGMP-dependent protein kinase (PKG)-induced Vasodilator-Stimulated-Phosphoprotein (VASP) phosphorylation; iv) activation of the signalling molecules Phosphatidylinositol 3-Kinase (PI3-K)/Akt and Mitogen Activated Protein Kinase (MAPK)/ERK-1/2; and v) oxidative stress. Experiments were repeated in the presence of the nitric oxide donor Na-nitroprusside. We found that platelets constitutively express GLP-1R and that, independently of GLP-1R, GLP-1(7-36), GLP-1(9-36) and Liraglutide exert platelet inhibitory effects as shown by: a) increased NO-antiaggregating effects, b) increased the activation of the cGMP/PKG/VASP pathway, c) reduced the activation of PI3-K/Akt and MAPK/ERK-2 pathways, d) reduced the AA-induced oxidative stress. When the experiments were repeated in the presence of the antagonist of GLP-1R Exendin(9-39), the platelet inhibitory effects were maintained, thus indicating a mechanism independent of GLP-1R. In conclusion, GLP-1(7-36), its degradation product GLP-1(9-36) and Liraglutide exert similar inhibitory effects on platelet activation, suggesting a potential protective effect on the cardiovascular system.

Detection and management of retroperitoneal cystic lesions: A case report and review of the literature.

The identification of cystic lesions within the retroperitoneal space is a rare event that poses clinicians the challenge of a difficult diagnosis and disease management. Retroperitoneal cystic lesions account for a group of lesions that range from common benign lesions (e.g., lymphoceles developing as a surgical complication) to rare aggressive malignant neoplasms. Currently, in the majority of cases, image-guided procedures allow for a pathological diagnosis to be achieved in these challenging lesions, thus offering the chance of an appropriate treatment; however, the overall clinical assessment of retroperitoneal cysts is highly demanding. The present study reports the management of a representative clinical case, presenting with a voluminous cystic mass able to dislocate cave vein, whose diagnosis was preceded by a deep vein thrombosis. Computed tomography-scan and ultrasound guided percutaneous drainage were performed to achieve the diagnosis. Following the discussion of the current case report, a review of the pathological and radiological characteristics of retroperitoneal cystic lesions is presented.

Unleashing the Guardian: The Targetable BCR-ABL/HAUSP/PML/PTEN Network in Chronic Myeloid Leukemia.

The complete eradication of Chronic Myeloid Leukemia is still challenging even in the era of highly selective and potent BCR-ABL tyrosine kinase inhibitors (TKIs). The 'Achilles heel' of TKI-based CML therapy is the inability of TKI to effectively target CML stem cells. Several pathways have been described to induce TKI insensitiveness in quiescent CML stem cells. In this review, we will describe the BCR-ABL/HAUSP/PML/PTEN network, whose signaling mediators converge to regulate the function of the tumor suppressor PTEN. We will also highlight the pharmacological strategies to modulate PTEN functions in order to sustain CML stem cell eradication.

Therapeutic inhibition of USP7-PTEN network in chronic lymphocytic leukemia: a strategy to overcome TP53 mutated/deleted clones.

Chronic Lymphocytic Leukemia (CLL) is a lymphoproliferative disorder with either indolent or aggressive clinical course. Current treatment regiments have significantly improved the overall outcomes even if higher risk subgroups - those harboring TP53 mutations or deletions of the short arm of chromosome 17 (del17p) - remain highly challenging. In the present work, we identified USP7, a known de-ubiquitinase with multiple roles in cellular homeostasis, as a potential therapeutic target in CLL. We demonstrated that in primary CLL samples and in CLL cell lines USP7 is: i) over-expressed through a mechanism involving miR-338-3p and miR-181b deregulation; ii) functionally activated by Casein Kinase 2 (CK2), an upstream interactor known to be deregulated in CLL; iii) effectively targeted by the USP7 inhibitor P5091. Treatment of primary CLL samples and cell lines with P5091 induces cell growth arrest and apoptosis, through the restoration of PTEN nuclear pool, both in TP53-wild type and -null environment. Importantly, PTEN acts as the main tumor suppressive mediator along the USP7-PTEN axis in a p53 dispensable manner. In conclusion, we propose USP7 as a new druggable target in CLL.

Rare Bone Marrow Biopsy Complication: A Challenging Case of Sacroiliitis and Staphilococcus Aureus Sepsis.

Bone marrow biopsy is a mandatory procedure to diagnose several hematological disorders. This invasive analysis is generally safe and the procedure-related risks are rare and include bleeding at the site of puncture and, very occasionally, local infections. Here, we describe a case of sacroiliitis that occurred as a consequence of bone marrow biopsy.

The targetable role of herpes virus-associated ubiquitin-specific protease (HAUSP) in p190 BCR-ABL leukemia.

Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) is driven by the p190 breakpoint cluster region (BCR)-ABL isoform. Although effectively targeted by BCR-ABL tyrosine kinase inhibitors (TKIs), ALL is associated with a less effective response to TKIs compared with chronic myeloid leukemia. Therefore, the identification of additional genes required for ALL maintenance may provide possible therapeutic targets to aid the eradication of this cancer. The present study demonstrated that p190 BCR-ABL is able to interact with the deubiquitinase herpesvirus-associated ubiquitin-specific protease (HAUSP), which in turn affects p53 protein stability. Notably, the inhibition of HAUSP with small molecule inhibitors promoted the upregulation of p53 protein levels. These results suggest that HAUSP inhibitors may harbor clinically relevant implications in the treatment of Ph+ ALL.