Widespread genome hypo-methylation and promoter hyper-methylation of epithelium-specific genes are hallmarks of stable epithelial-to-mesenchymal transition (EMT), which in prostate cancer (PCa) ...correlates with castration resistance, cancer stem cells generation, chemoresistance and worst prognosis. Exploiting our consolidated 'ex-vivo' system, we show that cancer-associated fibroblasts (CAFs) released factors have pivotal roles in inducing genome methylation changes required for EMT and stemness in EMT-prone PCa cells. By global DNA methylation analysis and RNA-Seq, we provide compelling evidence that conditioned media from CAFs explanted from two unrelated patients with advanced PCa, stimulates concurrent DNA hypo- and hyper-methylation required for EMT and stemness in PC3 and DU145, but not in LN-CaP and its derivative C4-2B, PCa cells. CpG island (CGI) hyper-methylation associates with repression of genes required for epithelial maintenance and invasion antagonism, whereas activation of EMT markers and stemness genes correlate with CGI hypo-methylation. Remarkably, methylation variations and EMT-regulated transcripts almost completely reverse qualitatively and quantitatively during MET. Unsupervised clustering analysis of the PRAD TCGA data set with the differentially expressed (DE) and methylated EMT signature, identified a gene cluster of DE genes defined by a CAF+ and AR- phenotype and worst diagnosis. This gene cluster includes the relevant factors for EMT and stemness, which display DNA methylation variations in regulatory regions inversely correlated to their expression changes, thus strongly sustaining the ex-vivo data. DNMT3A-dependent methylation is essential for silencing epithelial maintenance and EMT counteracting genes, such as CDH1 and GRHL2, that is, the direct repressor of ZEB1, the key transcriptional factor for EMT and stemness. Accordingly, DNMT3A knock-down prevents EMT entry. These results shed light on the mechanisms of establishment and maintenance of coexisting DNA hypo- and hyper-methylation patterns during cancer progression, the generation of EMT and cell stemness in advanced PCa, and may pave the way to new therapeutic implications.
Estrogen effects on mammary epithelial and breast cancer (BC) cells are mediated by the nuclear receptors ERα and ERβ, transcription factors that display functional antagonism with each other, with ...ERβ acting as oncosuppressor and interfering with the effects of ERα on cell proliferation, tumor promotion and progression. Indeed, hormone-responsive, ERα+ BC cells often lack ERβ, which when present associates with a less aggressive clinical phenotype of the disease. Recent evidences point to a significant role of microRNAs (miRNAs) in BC, where specific miRNA expression profiles associate with distinct clinical and biological phenotypes of the lesion. Considering the possibility that ERβ might influence BC cell behavior via miRNAs, we compared miRNome expression in ERβ+ vs ERβ- hormone-responsive BC cells and found a widespread effect of this ER subtype on the expression pattern of these non-coding RNAs. More importantly, the expression pattern of 67 miRNAs, including 10 regulated by ERβ in BC cells, clearly distinguishes ERβ+, node-negative, from ERβ-, metastatic, mammary tumors. Molecular dissection of miRNA biogenesis revealed multiple mechanisms for direct regulation of this process by ERβ+ in BC cell nuclei. In particular, ERβ downregulates miR-30a by binding to two specific sites proximal to the gene and thereby inhibiting pri-miR synthesis. On the other hand, the receptor promotes miR-23b, -27b and 24-1 accumulation in the cell by binding in close proximity of the corresponding gene cluster and preventing in situ the inhibitory effects of ERα on pri-miR maturation by the p68/DDX5-Drosha microprocessor complex. These results indicate that cell autonomous regulation of miRNA expression is part of the mechanism of action of ERβ in BC cells and could contribute to establishment or maintenance of a less aggressive tumor phenotype mediated by this nuclear receptor.
The employment of advanced molecular biology technologies has expanded the diagnostic investigation of cardiomyopathies in dogs; these technologies have predominantly been performed on postmortem ...samples, although the recent use of endomyocardial biopsy in living dogs has enabled a better premortem diagnostic approach to study the myocardial injury.
Endomyocardial biopsies were collected in nine dogs with a dilated cardiomyopathy phenotype (DCM-p) and congestive heart failure and submitted to histologic examination, next-generation sequencing (NGS), and polymerase chain reaction analysis. Data from three healthy dogs (Fastq files) were retrieved from a previously approved study and used as a control group for ribonucleic acid sequencing.
Histologic examination revealed endocardial fibrosis in six of nine dogs, whereas lymphocytic interstitial infiltrates were detected in two of nine dogs, and lymphoplasmacytic and macrophage infiltrates were detected in one of nine dogs. On polymerase chain reaction analysis, two dogs tested positive for canine parvovirus two and one dog for canine distemper virus. Gene-expression pathways involved in cellular energy metabolism (especially carbohydrates-insulin) and cardiac structural proteins were different in all DCM-p dogs compared to those in the control group. When dogs with lymphocytic interstitial infiltrates were compared to those in the control group, NGS analysis revealed the predominant role of genes related to inflammation and pathogen infection.
Next-generation sequencing technology performed on in vivo endomyocardial biopsies has identified different molecular and genetic factors that could play a role in the development and/or progression of DCM-p in dogs.
An abstract of the study of Montico et al about the role of non-coding RNAs in resistance to targeted therapies in cutaneous melanoma is presented. Among other things activating BRAF mutations are ...effectively targeted by specific inhibitors, such as vemurafenib, which have shown important clinical responses in advanced cutaneous melanoma (CM). However, their clinical effectiveness is impaired by the emergence of an early drug resistance. Non coding RNAs (ncRNAs) are of increasing biologic and therapeutic relevance considering their role in modulating gene expression. RNA sequencing identified about 230 mapped InoRNAs significantly differentially expressed between VR-resistant and -sensitive CM cell lines, thus indicating a difference in the IncRNA expression profiles. Gene ontology analysis revealed that the top of the neighbor coding gene function of differentially expressed lncRNAs involved apoptosis and cellular component movement, including the TGF-β pathway genes. Though additional studies are required, our findings suggest that IncRNAs may be involved in BRAFi resistance by regulating the anti-apoptotic and tumor-progressive aspects of TGF-β signaling in CM.
Platelet activation triggers thrombus formation in physiological and pathological conditions, such as acute coronary syndromes. Current therapies still fail to prevent thrombotic events in numerous ...patients, indicating that the mechanisms modulating platelet response during activation need to be clarified. The evidence that platelets are capable of de novo protein synthesis in response to stimuli raised the issue of how megakaryocyte-derived mRNAs are regulated in these anucleate cell fragments. Proteogenomics was applied here to investigate this phenomeon in platelets activated in vitro with Collagen or Thrombin Receptor Activating Peptide. Combining proteomics and transcriptomics allowed in depth platelet proteome characterization, revealing a significant effect of either stimulus on proteome composition. In silico analysis revealed the presence of resident immature RNAs in resting platelets, characterized by retained introns, while unbiased proteogenomics correlated intron removal by RNA splicing with changes on proteome composition upon activation. This allowed identification of a set of transcripts undergoing maturation by intron removal during activation and resulting in accumulation of the corresponding peptides at exon-exon junctions. These results indicate that RNA splicing events occur in platelets during activation and that maturation of specific pre-mRNAs is part of the activation cascade, contributing to a dynamic fine-tuning of the transcriptome.
Abstract Diabetic foot (DF) is a chronic and highly disabling complication of diabetes. The prevalence of peripheral arterial disease (PAD) is high in diabetic patients and, associated or not with ...peripheral neuropathy (PN), can be found in 50% of cases of DF. It is worth pointing out that the number of major amputations in diabetic patients is still very high. Many PAD diabetic patients are not revascularised due to lack of technical expertise or, even worse, negative beliefs because of poor experience. This despite the progress obtained in the techniques of distal revascularisation that nowadays allow to reopen distal arteries of the leg and foot. Italy has one of the lowest prevalence rates of major amputations in Europe, and has a long tradition in the field of limb salvage by means of an aggressive approach in debridement, antibiotic therapy and distal revascularisation. Therefore, we believe it is appropriate to produce a consensus document concerning the treatment of PAD and limb salvage in diabetic patients, based on the Italian experience in this field, to share with the scientific community.
Diabetic foot syndrome (DFS) is a complex disease. The best outcomes are reported with the multi-disciplinary team (MDT) approach, where each member works collaboratively according to his/her ...expertise. However, which health provider should act as the team leader (TL) has not been determined.
The TL should be familiar with the management of diabetes, related complications and comorbidities. He/she should be able to diagnose and manage foot infections, including prompt surgical treatment of local lesions, such as abscesses or phlegmons, in an emergent way in the first meeting with the patient.
According to the Organization for Economic Co-operation and Development (OECD) reports, Italy is one of countries with a low amputation rate in diabetic patients. Many factors might have contributed to this result, including 1)the special attention directed to diabetes by the public health system, which has defined diabetes as a “protected disease”, and accordingly, offers diabetic patients, at no charge, the best specialist care, including specific devices, and 2)the presence of a network of diabetic foot (DF) clinics managed by diabetologists with medical and surgical expertise. The health care providers all share a “patient centred model” of care, for which they use their internal medicine background and skills in podiatric surgery to manage acute or chronic needs in a timely manner.
Therefore, according to Italian experiences, which are fully reported in this document, we believe that only a skilled diabetologist/endocrinologist should act as a TL. Courses and university master's degree programmes focused on DF should guarantee specific training for physicians to become a TL.
•Diabetic foot (DF) is a syndrome.•To properly manage DF, several specialists should collaborate in a team.•To reduce the burden of DF, diabetes should always be treated properly.•Specific care pathways guarantee low rates of major amputations.•Diabetologists are the natural team leaders.
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