Introduction: The approved dual-color fluorescence in situ hybridization (FISH) test for the detection of anaplastic lymphoma receptor tyrosine kinase (ALK) gene rearrangements in non-small-cell lung cancer (NSCLC) is complex and represents a low-throughput assay difficult to use in daily diagnostic practice. We devised a sensitive and robust routine diagnostic test for the detection of rearrangements and transcriptional up-regulation of ALK.
Methods: We developed a quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay adapted to RNA isolated from routine formalin-fixed, paraffin-embedded material and applied it to 652 NSCLC specimens. The reliability of this technique to detect ALK dysregulation was shown by comparison with FISH and immunohistochemistry.
Results: qRT-PCR analysis detected unbalanced ALK expression indicative of a gene rearrangement in 24 (4.6%) and full-length ALK transcript expression in six (1.1%) of 523 interpretable tumors. Among 182 tumors simultaneously analyzed by FISH and qRT-PCR, the latter accurately typed 97% of 19 rearranged and 158 nonrearranged tumors and identified ALK deregulation in two cases with insufficient FISH. Six tumors expressing full-length ALK transcripts did not show rearrangements of the gene. Immunohistochemistry detected ALK protein overexpression in tumors with gene fusions and transcriptional up-regulation, but did not distinguish between the two. One case with full-length ALK expression carried a heterozygous point mutation (S1220Y) within the kinase domain potentially interfering with kinase activity and/or inhibitor binding.
Conclusions: Our qRT-PCR assay reliably identifies and distinguishes ALK rearrangements and full-length transcript expression in formalin-fixed, paraffin-embedded material. It is an easy-to-perform, cost-effective, and high-throughput tool for the diagnosis of ALK activation. The expression of full-length ALK transcripts may be relevant for ALK inhibitor therapy in NSCLC.
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http://dx.doi.org/10.1097/JTO.0000000000000068 | DOI Listing |
Mil Med Res
July 2024
Hunan Provincial Key Laboratory of Neurorestoratology, 921 Hospital of Joint Logistics Support Force People's Liberation Army of China, (the Second Affiliated Hospital of Hunan Normal University), Changsha, 410003, China.
Background: Parkinson's disease (PD) is a neurodegenerative disorder characterized by the degeneration of dopaminergic neurons in the substantia nigra (SN). Activation of the neuroinflammatory response has a pivotal role in PD. Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic approach for various nerve injuries, but there are limited reports on their use in PD and the underlying mechanisms remain unclear.
View Article and Find Full Text PDFAntibodies (Basel)
May 2024
Center for Antibody Therapeutics, Division of Infectious Diseases, Department of Medicine, University of Pittsburgh Medical School, Pittsburgh, PA 15261, USA.
World Allergy Organ J
March 2024
National Centre for Hereditary Angioedema, Clinic of Children and Adolescents, Clinics of Pulmonology and Phthisiology, Jessenius Faculty of Medicine, Comenius University in Bratislava, University Hospital in Martin, Slovakia.
Background: Hereditary angioedema (HAE) is a rare autosomal dominant genetic disease characterised by acute episodes of non-pruritic skin and submucosal swelling caused by increase in vascular permeability.
Objective: Here we present the first complex analysis of the National HAE Slovakian cohort with the detection of 12 previously un-published genetic variants in gene.
Methods: In patients diagnosed with hereditary angioedema caused by deficiency or dysfunction of C1 inhibitor (C1-INH-HAE) based on clinical manifestation and complement measurements, gene was tested by DNA sequencing (Sanger sequencing/massive parallel sequencing) and/or multiplex ligation-dependent probe amplification for detection of large rearrangements.
Front Oncol
January 2024
Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Objective: To assess the influence of F1174S mutation on kinase activity and drug sensitivity of the echinoderm microtubule-associated protein-like 4 (EML4) and anaplastic lymphoma kinase (ALK) fusion (EML4-ALK) variants 1 and 3.
Methods: We constructed mammalian expression plasmids of both wildtype and F1174 mutant EML4-ALK variants 1 and 3, and then characterized them with cell models by performing immunoblotting, neurite outgrowth assay, focus formation assay as well as protein stability assay. Drug sensitivity to ALK tyrosine kinase inhibitors was also compared between wildtype and F1174 mutant EML4-ALK fusions.
Int J Mol Sci
September 2023
Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2R3, Canada.
In ALK-positive anaplastic large cell lymphoma (ALK+ALCL), a small subset of cancer stem-like (or RR) cells characterized by high Myc expression have been identified. We hypothesize that NPM-ALK contributes to their high Myc expression. While transfection of into HEK293 cells effectively increased Myc by inhibiting its proteosomal degradation (PD-Myc), this effect was dramatically attenuated when the full-length NPM1 (FL-NPM1) was downregulated using shRNA, highlighting the importance of the NPM-ALK:FL-ALK heterodimers in this context.
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