483 research outputs found
Drug repurposing against COVID-19. focus on anticancer agents
The very limited time allowed to face the COVID-19 pandemic poses a pressing challenge to find proper therapeutic approaches. However, synthesis and full investigation from preclinical studies to phase III trials of new medications is a time-consuming procedure, and not viable in a global emergency, such as the one we are facing
Inducers of epithelial mesenchymal transition and cancer stem cells in malignant pleural effusions
The Epithelial to Mesenchymal Transition (EMT) plays a role not
only in tumor metastasis but also in tumor recurrence. This process
is believed to be tightly linked to the presence of Cancer Stem Cells
(CSCs) however, it is still not clear which factors could induce EMT
and how it could be a source for CSCs. It has been demonstrated
that Malignant Pleural Effusion (MPEs) may represent an excellent
source to identify markers and molecular mechanisms involved in
EMT and CSCs development. Growth factors, cell differentiation
markers and molecular adhesion are involved in some of the crucial
neoplastic cell events such as proliferation, metastasis, resistance
to chemotherapy and EMT. In this review, we summarize the current
understanding of which molecular markers can orchestrate EMT and
CSCs in MPEs
Cancer stem cells and the slow cycling phenotype. how to cut the gordian knot driving resistance to therapy in melanoma
Cancer stem cells (CSCs) have historically been defined as slow cycling elements that are able to differentiate into mature cells but without dedifferentiation in the opposite direction. Thanks to advances in genomic and non-genomic technologies, the CSC theory has more recently been reconsidered in a dynamic manner according to a “phenotype switching” plastic model. Transcriptional reprogramming rewires this plasticity and enables heterogeneous tumors to influence cancer progression and to adapt themselves to drug exposure by selecting a subpopulation of slow cycling cells, similar in nature to the originally defined CSCs. This model has been conceptualized for malignant melanoma tailored to explain resistance to target therapies. Here, we conducted a bioinformatics analysis of available data directed to the identification of the molecular pathways sustaining slow cycling melanoma stem cells. Using this approach, we identified a signature of 25 genes that were assigned to four major clusters, namely 1) kinases and metabolic changes, 2) melanoma-associated proteins, 3) Hippo pathway and 4) slow cycling/CSCs factors. Furthermore, we show how a protein−protein interaction network may be the main driver of these melanoma cell subpopulations. Finally, mining The Cancer Genome Atlas (TCGA) data we evaluated the expression levels of this signature in the four melanoma mutational subtypes. The concomitant alteration of these genes correlates with the worst overall survival (OS) for melanoma patients harboring BRAF-mutations. All together these results underscore the potentiality to target this signature to selectively kill CSCs and to achieve disease control in melanoma
Rapid on-site evaluation (ROSE) in pancreatic cancer diagnosis. doing more with less
Rapid on-site evaluation (ROSE) in pancreatic cancer
diagnosis: Doing more with les
Clinical-pathological features of an occult mixed mucinous male breast cancer. a case report
Mucinous carcinoma of the male breast is an uncommon malignant breast neoplasm and its diagnoses remain difficult. It is probably due to such a low rate of breast cancer cases that men tend to be diagnosed at an older age than women and with a later stage of the disease. We describe a case of a 69-year-old male who displayed a palpable lump in his right axilla several years ago, showing signs of cutaneous adnexal mucinous adenocarcinoma after biopsy. After six years and several clinical examination and systemic investigation without results, the patient underwent to fine needle aspiration cytology and subsequently a biopsy of a mass with irregular margins in the retroareolar region of his right breast. The final diagnosis was of a mixed mucinous breast cancer with neuroendocrine differentiation. The tumor cells phenotype showed Synaptophisin (+), CEA (+/-), CK-20 (-), CK-7 (+), TTF-1 (-), estrogen receptor (-), progesterone (-) and HER 2 (++). These results were unusual for a mucinous male breast carcinoma. In the presence of a lesion in the axillary area with no specific primary origin, breast cancer should never be ruled out, even in the absence of clinical evidence and with an immunohistochemical pattern not indicative of mammary origin
MicroRNAs in melanoma development and resistance to target therapy
microRNAs constitute a complex class of pleiotropic post-transcriptional regulators of gene expression involved in the control of several physiologic and pathologic processes. Their mechanism of action is primarily based on the imperfect matching of a seed region located at the 5' end of a 21-23 nt sequence with a partially complementary sequence located in the 3' untranslated region of target mRNAs. This leads to inhibition of mRNA translation and eventually to its degradation. Individual miRNAs are capable of binding to several mRNAs and several miRNAs are capable of influencing the function of the same mRNAs. In recent years networks of miRNAs are emerging as capable of controlling key signaling pathways responsible for the growth and propagation of cancer cells. Furthermore several examples have been provided which highlight the involvement of miRNAs in the development of resistance to targeted drug therapies. In this review we provide an updated overview of the role of miRNAs in the development of melanoma and the identification of the main downstream pathways controlled by these miRNAs. Furthermore we discuss a group of miRNAs capable to influence through their respective up- or down-modulation the development of resistance to BRAF and MEK inhibitors
BDNF/TrkB axis activation promotes epithelial-mesenchymal transition in idiopathic pulmonary fibrosis
Background: Neurotrophins (NT) belongs to a family of growth factors which promotes neurons survival and differentiation. Increasing evidence show that NT and their receptor are expressed in lung tissues suggesting a possible role in lung health and disease. Here we investigated the expression and functional role of the TrkB/BDNF axis in idiopathic pulmonary fibrotic lung (myo)fibroblasts. Methods: Lung fibroblast were isolated from IPF patients and characterized for the expression of mesenchymal markers in comparison to normal lung fibroblasts isolated from non-IPF controls. Results: BDNF treatment promoted mesenchymal differentiation and this effect was counteracted by the TrkB inhibitor K252a. In this regard, we showed that K252a treatment was able to control the expression of transcription factors involved in epithelial to mesenchymal transition (EMT). Accordingly, K252a treatment reduced matrix metalloproteinase-9 enzyme activity and E-cadherin expression while increased cytoplasmic β-catenin expression. Conclusions: Our results suggest that BDNF/TrkB axis plays a role in EMT promoting the acquisition of (myo)fibroblast cell phenotype in IPF. Targeting BDNF/TrkB seems to represent a viable approach in order to prevent EMT dependent lung fibrosis
MOD derived pyrochlore films as buffer layer for all-chemical YBCO coated conductors
We report a detailed study performed on La2Zr2O7 (LZO) pyrochlore material
grown by Metal-Organic Decomposition (MOD) method as buffer layers for
YBa2Cu3O7-x (YBCO) coated conductors. High quality epitaxial LZO thin films
have been obtained on single crystal (SC) and Ni-5%at.W substrates. In order to
evaluate structural and morphological properties, films have been characterized
by means of X-ray diffraction analyses (XRD), atomic force microscope (AFM) and
scanning electron microscope (SEM). Precursors solutions and heat treatments
have been studied by thermogravimetric analyses (TG-DTA-DTG) and infrared
spectra (FT-IR) with the aim of optimizing the annealing process. Thin films of
YBCO have been deposited by pulsed laser ablation (PLD) on this buffer layers.
The best results obtained on SC showed YBCO films with critical temperature
values above 90 K, high self field critical current density values (Jc > 1
MA/cm2) and high irreversibility field values (8.3 T) at 77 K together with a
rather high depinning frequency vp (0.5 T, 77 K)>44 GHz as determined at
microwaves. The best results on Ni-5%at.W has been obtained introducing in the
heat treatment a pyrolysis process at low temperature in air in order to remove
the residual organic part of the precursor solution
Risk factors for Haemophilus influenzae and pneumococcal respiratory tract colonization in CVID
To the Editor:
Disease-specific studies focused on infection risk in common variable immune deficiencies (CVIDs) are needed to define strategies for controlling respiratory infections predominantly due to bacteria such as Streptococcus pneumoniae and Haemophilus influenzae.1 Little information is available on the rate of airway bacterial carriage and its consequence in hypogammaglobulinemias. Despite IgG replacement, recurrent respiratory infections are common in CVID, possibly leading to chronic lung damage2 and poor quality of life.3 Thus, patients are often prescribed antibiotics and/or long-term antimicrobial prophylactic regimens. Several regimens are used including rotation or periodically changing antibiotics.4 However, antibiotics influence antimicrobial resistance among airway microbiota. In a recent meta-analysis on patients with chronic lung diseases, 30% of S pneumoniae showed resistance to macrolides.
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ErbB3 Phosphorylation as Central Event in Adaptive Resistance to Targeted Therapy in Metastatic Melanoma. Early Detection in CTCs during Therapy and Insights into Regulation by Autocrine Neuregulin
In recent years the introduction of target therapies with BRAF and MEK inhibitors (MAPKi) and of immunotherapy with anti-CTLA-4 and anti-PD-1 monoclonal antibodies have dramatically improved survival of metastatic melanoma patients. Despite these changes drug resistance remains a major hurdle. Several mechanisms are at the basis of drug resistance. Particular attention has been devoted over the last years to unravel mechanisms at the basis of adaptive/non genetic resistance occurring in BRAF mutated melanomas upon treatment with to MAPKi. In this paper we focus on the involvement of activation of ErbB3 receptor following early exposure of melanoma cells to BRAF or MEK inhibitors, and the following induction of PI3K/AKT pathway. Although different mechanisms have been invoked in the past at the basis of this activation we show here with a combination of approaches that autocrine production of neuregulin by melanoma cells is a major factor responsible for ErbB3 phosphorylation and downstream AKT activation. Interestingly the kinetic of neuregulin production and of the ensuing ErbB3 phosphorylation is different in different melanoma cell lines which underscores the high degree of tumor heterogeneity. Moreover, heterogeneity is further highlighted by the evidence that in different cell lines neuregulin upregulation can occur at the transcriptional or at the post-transcritpional level. Finally we complement our study by showing with a liquid biopsy assay that circulating tumor cells (CTCs) from melanoma patients undergo upregulation of ErbB3 phosphorylation in vivo shortly after initiation of therapy
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