1,720,969 research outputs found
ALK gene alterations in cancer: Biological aspects and therapeutic implications
No full textALK was first reported in 1994 as a translocation in anaplastic large cell lymphoma and then described with different abnormalities in a number of tumors. Recently, a shortly accumulated biomedical research clarified the numerous biological processes underlying its ability to support cancer development, growth and progression. Advent of precision medicine has finally provided unexpected advances, leading to the development of ALK-targeting inhibitors with superior efficacy as compared with standard chemotherapy regimens, as well as the identification of resistance mechanisms and the creation of 'next-generation' treatments. This review summarizes the current understanding of ALK-driven cancers from the oncogenesis and mutation frequency by The Cancer Genome Atlas database through the diagnostic approach, to an updated portrait of available tyrosine kinase inhibitors, considering their effectiveness in cancer treatment, the molecular reasons of therapeutic failure, and the actual and future ways to overcome resistances
[Genomics of lung adenocarcinoma: pathogenetic significance and clinical applications.]
No full textDiagnostic and therapeutic approaches to non small cell lung cancer (NSCLC), especially adenocarcinoma, have recently undergone dramatic evolution according to the tremendous amount of molecular data collected on this cancer. In fact, the application of oncogenomics has identified novel molecular subtypes of NSCLC and led the way to diagnostic criteria based on the expression of specific genetic alterations that can provide prognostic and specific indications to the molecular targeted therapies. In NSCLC, several genes show "driver" molecular alterations that confer oncogenic potential to progenitor cells through the enrollment of metabolic pathways critical for cell proliferation and tumor development. On the other hand, clinical management of NSCLC with small molecules has undoubtedly provided optimistic results with both a significant increase in overall survival and reduction in therapy-related toxicity including relative complications. Thus, pharmacogenomics, as the newest tool for using the targeted therapy represents the most innovative approach for treatment of this cancer once the molecular aberrations are identified. In particular, the relative mutational status of several driver genes including EGFR, ALK, ROS1 and others, is directly correlated to a better response to thyrosin-kinase inhibitors. Furthermore, other therapeutic strategies with inhibitors of angiogenic receptors, PARP, histone-deacetylase, PI3K and HSP90, are intensively studied in pre-clinical models as well as in clinical trials for a potential adoption in clinical practice. The introduction of more advanced techniques for molecular profiling also allows to identify pathogenic variants of many other genes involved in the progression of lung adenocarcinoma with the aim to develop novel molecular targets for pharmacological research. In this review, we will revisit the current applications of oncogenomics in the diagnosis and treatment of this tumor
Characterization of a Rare Nonpathogenic Methylenetetrahydrofolatereductase (MTHFR) Gene Mutation p.Lys215del in a Southern Italian family
No full textThe Tumor Microenvironment in Neuroendocrine Tumors: Biology and Therapeutic Implications
No full textNeuroendocrine tumors (NETs) include a heterogeneous group of malignancies arising in the diffuse neuroendocrine system and characterized by indolent growth. Complex interactions take place among the cellular components of the microenvironment of these tumors, and the recognition of the molecular mediators of their interplay and cross-talk is crucial to discover novel therapeutic targets. NET cells overexpress a plethora of proangiogenic molecules including VEGF, PDGF, FGF, semaphorins and angiopoietins, that promote both recruitment and proliferation of endothelial cell precursors, thus resulting among the most vascularized cancers with a microvessel density 10-fold higher then epithelial tumors. Also, NETs operate multi-faceted interactions with stromal cells, both at local and distant sites, and whether their paracrine secretion of serotonin, CTGF and TGF-β primarily drives the fibroblast activation to enhance the tumor proliferation, on the other side NET-derived profibrotic factors accelerate the extracellular matrix remodeling and contribute to heart valves and/or mesenteric fibrosis development, namely major complications of functioning NETs. However, at present little is known on the immune landscape of NETs, but accumulating evidence shows that tumor-infiltrating neutrophils, mast cells and/or macrophages concur to promote the neoangiogenic switch of these tumors by either direct or indirect mechanisms. On the other hand, immune checkpoint molecules are heterogeneously expressed in NETs' surrounding cells, and it is unclear whether or not tumor-infiltrating lymphocytes are anti-tumor armed within the microenvironment, given their low mutational load. Here, we review the current knowledge on both gastroenteropancreatic and pulmonary NETs' microenvironment as well as both established and innovative treatments aimed at targeting the tumor-host interplay.
Next-generation Sequencing (NGS) Analysis on Single Circulating Tumor Cells (CTCs) with No Need of Whole-genome Amplification (WGA)
Full text linkBackground: Isolation and genotyping of circulating tumor cells (CTCs) is gaining an increasing interest by clinical researchers in oncology not only for investigative purposes, but also for concrete application in clinical practice in terms of diagnosis, prognosis and decision treatment with targeted therapies. For the mutational analysis of single CTCs, the most advanced biotechnology methodology currently available includes the combination of whole genome amplification (WGA) followed by next-generation sequencing (NGS). However, the sequence of these molecular techniques is time-consuming and may also favor operator-dependent errors, related to the procedures themselves that, as in the case of the WGA technique, might affect downstream molecular analyses. Materials and Methods: A preliminary approach of molecular analysis by NGS on a model of CTCs without previous WGA procedural step was performed. We set-up an artificial sample obtained by spiking the SK-MEL-28 melanoma cell line in normal donor peripheral whole blood. Melanoma cells were first enriched using an AutoMACS® (Miltenyi) cell separator and then isolated as single and pooled CTCs by DEPArrayTM System (Silicon Biosystems). NGS analysis, using the Ion AmpliSeqTM Cancer Hotspot Panel v2 (Life Technologies) with the Ion Torrent PGMTM system (Life Technologies), was performed on the SK-MEL-28 cell pellet, a single CTC previously processed with WGA and on 1, 2, 4 and 8 recovered CTCs without WGA pre-amplification. Results: NGS directly carried out on CTCs without WGA showed the same mutations identified in SK-MEL-28 cell line pellet, with a considerable efficiency and avoiding the errors induced by the WGA procedure. Conclusion: We identified a cost-effective, time-saving and reliable methodological approach that could improve the analytical accuracy of the liquid biopsy and appears promising in studying CTCs from cancer patients for both research and clinical purposes
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Characterization of a rare nonpathogenic sequence variant (c.1905C>T) of the dihydropyrimidine dehydrogenase gene (DPYD)
Full text linkBackground
In the era of precision medicine, the suitability of fluoropyrimidine therapies in clinical oncology can be checked by pharmacogenetic investigations of single patients, thus optimizing resources and indicating the appropriate drugs to personalize their chemotherapy. For example, the presence of dihydropyrimidine dehydrogenase gene (DPYD) polymorphisms in cancer patients may lead to adverse effects when adopting fluoropyrimidine-based therapies.
Methods
We detected in a cancer patient a rare germline synonymous heterozygous variant of DPYD (c.1905C>T) in proximity to the exon 14 splice donor site. Because in silico analyses hypothesized potential deleterious effects of the splice site, we performed both quantitative and qualitative mRNA analyses to investigate the possible pathogenic nature of the variant.
Results
We did not detect any alterations in mRNA expression or in the cDNA sequence of DPYD gene transcript.
Conclusions
Our observations suggest that the c.1905C>T variant of DPYD does not have a pathogenic effect. Therefore, assessment of the clinical significance of rare sequence variants could emphasize the predictive value of DPYD gene alterations in identifying patients at potential risk for fluoropyrimidine-related toxicity
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