Early prolonged prone position in noninvasively ventilated patients with SARS-CoV-2-related moderate-to-severe hypoxemic respiratory failure: clinical outcomes and mechanisms for treatment response in the PRO-NIV study.

BACKGROUND: Whether prone position (PP) improves clinical outcomes in COVID-19 pneumonia treated with noninvasive ventilation (NIV) is unknown. We evaluated the effect of early PP on 28-day NIV failure, intubation and death in noninvasively ventilated patients with moderate-to-severe acute hypoxemic respiratory failure due to COVID-19 pneumonia and explored physiological mechanisms underlying treatment response. METHODS: In this controlled non-randomized trial, 81 consecutive prospectively enrolled patients with COVID-19 pneumonia and moderate-to-severe (paO2/FiO2 ratio < 200) acute hypoxemic respiratory failure treated with early PP + NIV during Dec 2020-May 2021were compared with 162 consecutive patients with COVID-19 pneumonia matched for age, mortality risk, severity of illness and paO2/FiO2 ratio at admission, treated with conventional (supine) NIV during Apr 2020-Dec 2020 at HUMANITAS Gradenigo Subintensive Care Unit, after propensity score adjustment for multiple baseline and treatment-related variables to limit confounding. Lung ultrasonography (LUS) was performed at baseline and at day 5. Ventilatory parameters, physiological dead space indices (DSIs) and circulating inflammatory and procoagulative biomarkers were monitored during the initial 7 days. RESULTS: In the intention-to-treat analysis. NIV failure occurred in 14 (17%) of PP patients versus 70 (43%) of controls [HR = 0.32, 95% CI 0.21-0.50; p < 0.0001]; intubation in 8 (11%) of PP patients versus 44 (30%) of controls [HR = 0.31, 95% CI 0.18-0.55; p = 0.0012], death in 10 (12%) of PP patients versus 59 (36%) of controls [HR = 0.27, 95% CI 0.17-0.44; p < 0.0001]. The effect remained significant within different categories of severity of hypoxemia (paO2/FiO2 < 100 or paO2/FiO2 100-199 at admission). Adverse events were rare and evenly distributed. Compared with controls, PP therapy was associated with improved oxygenation and DSIs, reduced global LUS severity indices largely through enhanced reaeration of dorso-lateral lung regions, and an earlier decline in inflammatory markers and D-dimer. In multivariate analysis, day 1 CO2 response outperformed O2 response as a predictor of LUS changes, NIV failure, intubation and death. CONCLUSION: Early prolonged PP is safe and is associated with lower NIV failure, intubation and death rates in noninvasively ventilated patients with COVID-19-related moderate-to-severe hypoxemic respiratory failure. Early dead space reduction and reaeration of dorso-lateral lung regions predicted clinical outcomes in our study population. CLINICAL TRIAL REGISTRATION: ISRCTN23016116 . Retrospectively registered on May 1, 2021.

Diffusion-weighted quantitative MRI to diagnose benign conditions from malignancies of the anterior mediastinum: Improvement of diagnostic accuracy by comparing perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient.

PURPOSE: To compare perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient (ADC) to diagnose benign conditions from malignancies of the anterior mediastinum. MATERIALS AND METHODS: Seventy-six subjects were divided into a "benign conditions" group (A, n = 44) and a "malignancies" group (B, n = 32), based on histological findings. diffusion-weighted magnetic resonance imaging (DW-MRI) was performed at b of 0/150/800 sec/mm(2) . The ADCs were obtained on an ADC map by including (perfusion-sensitive = ADCb0-800 ) and excluding (perfusion-free = ADCb150-800 ) the b = 0 sec/mm(2) . The Mann-Whitney U-test was used to detect differences in ADCb0-800 compared with ADCb150-800 values between all cases, benign conditions, and malignancies. The same test was used to evaluate differences in ADCs between the two groups for each type of measurement (ADCb0-800 and ADCb150-800 ), and receiver-operating characteristic (ROC) curves were obtained to evaluate discrimination abilities with comparison of areas-under-ROC-curves (AUROC). Optimal cutpoints for discrimination between groups were determined by the Youden-Index with computation of accuracy. RESULTS: The median ADCb0-800 was significantly greater compared with ADCb150-800 for all cases (P = 0.0014), benign conditions (P = 0.0412), and malignancies (P = 0.0001). The median percentage of increase was 5.30% for group-A and 22.39% for group-B (P < 0.0001). AUROC of ADC in discriminating between groups was significantly greater for ADCb150-800 (0.932) compared with ADCb0-800 (0.831) (P = 0.001). The optimal cutpoint for distinction between groups was 1.52 × 10(-3) mm(2) /sec (sensitivity = 93.7%, specificity = 88.6%, accuracy = 90.8%) for ADCb150-800 and 1.75 × 10(-3) mm(2) /sec (sensitivity = 75.0%, specificity = 79.5%, accuracy = 77.6%) for ADCb0-800 . CONCLUSION: The use of perfusion-free ADC measurements significantly improves diagnostic accuracy of DW-MRI in differentiating benign conditions from malignancies of the anterior mediastinum. J. Magn. Reson. Imaging 2016;44:758-769.

A preclinical algorithm of soluble surrogate biomarkers that correlate with therapeutic inhibition of the MET oncogene in gastric tumors.

The MET oncogene is amplified in a fraction of human gastric carcinoma cell lines, with consequent overexpression and constitutive activation of the corresponding protein product, the Met tyrosine kinase receptor. This genetically driven hyperactivation of Met is necessary for cancer cell growth and survival, so that Met pharmacological blockade results in cell-cycle arrest or apoptosis (oncogene addiction). MET gene amplification also occurs in vivo in a number of human gastric carcinomas, and clinical trials are now ongoing to assess the therapeutic efficacy of Met inhibitors in this type of malignancy. The aim of our study was to identify a preclinical algorithm of soluble surrogate biomarkers indicative of response to Met inhibition in gastric tumors, as a potential tool to integrate imaging criteria during patient follow-up. We started from a survey of candidate molecules based on antibody proteomics and gene expression profiling; after ELISA validation and analytical quantification, four biomarkers were identified that appeared to be strongly and consistently modulated by Met inhibition in a panel of Met-addicted gastric carcinoma cell lines, but not in Met-independent cell lines. Pharmacologic blockade of Met using specific small-molecule inhibitors led to reduced secretion of IL-8, GROα and the soluble form of uPAR and to increased production of IL-6 both in vitro (in culture supernatants) and in vivo (in the plasma of xenografted mice). If confirmed in patients, this information might prove useful to monitor clinical response to Met-targeted therapies in MET-amplified gastric carcinomas.

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.

The BCR-ABL/NF-κB signal transduction network: a long lasting relationship in Philadelphia positive Leukemias.

The Nuclear Factor-kappa B (NF-κB) family of transcription factors plays a key role in cancer pathogenesis due to the ability to promote cellular proliferation and survival, to induce resistance to chemotherapy and to mediate invasion and metastasis. NF-κB is recruited through different mechanisms involving either canonical (RelA/p50) or non-canonical pathways (RelB/p50 or RelB/p52), which transduce the signals originated from growth-factors, cytokines, oncogenic stress and DNA damage, bacterial and viral products or other stimuli. The pharmacological inhibition of the NF-κB pathway has clearly been associated with significant clinical activity in different cancers. Almost 20 years ago, NF-κB was described as an essential modulator of BCR-ABL signaling in Chronic Myeloid Leukemia and Philadelphia-positive Acute Lymphoblastic Leukemia. This review summarizes the role of NF-κB in BCR-ABL-mediated leukemogenesis and provides new insights on the long lasting BCR-ABL/NF-κB connection.

The Role of PTEN in Myeloid Malignancies.

PTEN deletion in the mouse and in the zebrafish highlights the essential role of this tumor suppressor in the development of myeloid malignancies, in particular acute myeloid leukemia and myeloproliferative disorders. In humans, extensive genetic sequences of myeloid malignancies did not reveal recurrent PTEN mutations and deletions. However, PTEN was shown to be functionally inactivated in several acute myeloid leukemia and chronic myeloid leukemia samples, through both post-trasductional modifications, changes in protein levels and cellular compartmentalization. Notably, non genomic inactivation of PTEN in myeloid malignancies could represent a challenging therapeutic opportunity for these diseases. Targeting those mechanisms that affect PTEN function could indeed promote PTEN reactivation with consequent cancer selective apoptosis induction. In this review we will describe the role of PTEN in the development of myeloid malignancies.

New alternative splicing BCR/ABL-OOF shows an oncogenic role by lack of inhibition of BCR GTPase activity and an increased of persistence of Rac activation in chronic myeloid leukemia.

In Chronic Myeloid Leukemia 80% of patients present alternative splice variants involving BCR exons 1, 13 or 14 and ABL exon 4, with a consequent impairment in the reading frame of the ABL gene. Therefore BCR/ABL fusion proteins (BCR/ABL-OOF) are characterized by an in-frame BCR portion followed by an amino acids sequence arising from the out of frame (OOF) reading of the ABL gene. The product of this new transcript contains the characteristic BCR domains while lacking the COOH-terminal Rho GTPase GAP domain. The present work aims to characterize the protein functionality in terms of cytoskeleton (re-)modelling, adhesion and activation of canonical oncogenic signalling pathways. Here, we show that BCR/ABL-OOF has a peculiar endosomal localization which affects EGF receptor activation and turnover. Moreover, we demonstrate that BCR/ABL-OOF expression leads to aberrant cellular adhesion due to the activation of Rac GTPase, increase in cellular proliferation, migration and survival. When overexpressed in a BCR/ABL positive cell line, BCR/ABL-OOF induces hyperactivation of Rac signaling axis offering a therapeutic window for Rac-targeted therapy. Our data support a critical role of BCR/ABL-OOF in leukemogenesis and identify a subset of patients that may benefit from Rac-targeted therapies.

Non genomic loss of function of tumor suppressors in CML: BCR-ABL promotes IκBα mediated p53 nuclear exclusion.

Tumor suppressor function can be modulated by subtle variation of expression levels, proper cellular compartmentalization and post-translational modifications, such as phosphorylation, acetylation and sumoylation. The non-genomic loss of function of tumor suppressors offers a challenging therapeutic opportunity. The reactivation of a tumor suppressor could indeed promote selective apoptosis of cancer cells without affecting normal cells. The identification of mechanisms that affect tumor suppressor functions is therefore essential. In this work, we show that BCR-ABL promotes the accumulation of the NFKBIA gene product, IκBα, in the cytosol through physical interaction and stabilization of the protein. Furthermore, BCR-ABL/IκBα complex acts as a scaffold protein favoring p53 nuclear exclusion. We therefore identify a novel BCR-ABL/IκBα/p53 network, whereby BCR-ABL functionally inactivates a key tumor suppressor.