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1.
Biomed Rep ; 21(2): 112, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38912171

RESUMO

Late-stage cancers lack effective treatment, underscoring the need for early diagnosis to improve prognosis and decrease mortality rates. Molecular markers, such as DNA methylation, offer promise in early cancer detection. The present study compared commercial kits for analyzing DNA from cervical liquid cytology samples in cancer screening. Rapid bisulfite conversion kits using silica spin-columns and magnetic beads were assessed against standard DNA extraction and bisulfite conversion methods for profiling DNA methylation using quantitative methylation-specific PCR. ß-actin amplification indicated the suitability of small sample volumes for methylation studies using either the pellet or supernatant (cell-free DNA) parts. Comparison of Bisulfite Conversion Kit-Whole Cell (Abcam), Methylamp Bisulfite Modification (Epigentek), EpiTect Fast LyseAll Bisulfite Kit (Qiagen GmbH) and EZ DNA Methylation-Direct Kit (Zymo Research Corp.) showed no significant differences in ß-actin cycle threshold values. EZ-96 DNA Methylation-Lightning MagPrep (Zymo Research Corp.), a hybrid kit in a 96-well plate format, exhibited swift turnaround time and similar amplification efficiency. Automation with magnetic bead kits increased throughput without compromising amplification efficiency in open PCR systems. Cost analysis favored direct kits over the gold standard manual protocol. This comparison aids in selecting cost-effective DNA methylation diagnostic tests. The present study confirmed comparable kit performance in methylation-based analysis, highlighting the adequacy of cytology samples and the potential of bodily fluids as alternatives for liquid biopsy.

2.
J Vis Exp ; (196)2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37395575

RESUMO

Calcitonin gene-related peptide (CGRP) is a vasoactive neuropeptide that plays a putative role in the pathophysiology of migraine headaches and may be a candidate for biomarker status. CGRP is released from neuronal fibers upon activation and induces sterile neurogenic inflammation and arterial vasodilation in the vasculature that receives trigeminal efferent innervation. The presence of CGRP in the peripheral vasculature has spurred investigations to detect and quantify this neuropeptide in human plasma using proteomic assays, such as the enzyme-linked immunosorbent assay (ELISA). However, its half-life of 6.9 min and the variability in technical details of assay protocols, which are often not fully described, have yielded inconsistent CGRP ELISA data in the literature. Here, a modified ELISA protocol for the purification and quantification of CGRP in human plasma is presented. The procedural steps involve sample collection and preparation, extraction using a polar sorbent as a means of purification, additional steps to block non-specific binding, and quantification via ELISA. Further, the protocol has been validated with spike and recovery and linearity of dilution experiments. This validated protocol can theoretically be used to quantify CGRP concentrations in the plasma of individuals not only with migraine, but also with other diseases in which CGRP may play a role.


Assuntos
Transtornos de Enxaqueca , Neuropeptídeos , Humanos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Proteômica , Transtornos de Enxaqueca/metabolismo , Neuropeptídeos/metabolismo , Neurônios/metabolismo , Ensaio de Imunoadsorção Enzimática
3.
JAMA Netw Open ; 6(2): e2255971, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36787144

RESUMO

This case series assesses the incidence of human papillomavirus (HPV)-associated sinonasal squamous cell carcinoma (SNSCC) and the prevalence of HPV-positive SNSCC among US adults.


Assuntos
Carcinoma de Células Escamosas , Seios Paranasais , Humanos , Adulto , Papillomavirus Humano , Incidência , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia
4.
Immun Inflamm Dis ; 10(6): e634, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35634961

RESUMO

INTRODUCTION: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic revealed a worldwide lack of effective molecular surveillance networks at local, state, and national levels, which are essential to identify, monitor, and limit viral community spread. SARS-CoV-2 variants of concern (VOCs) such as Alpha and Omicron, which show increased transmissibility and immune evasion, rapidly became dominant VOCs worldwide. Our objective was to develop an evidenced-based genomic surveillance algorithm, combining reverse transcription polymerase chain reaction (RT-PCR) and sequencing technologies to quickly identify highly contagious VOCs, before cases accumulate exponentially. METHODS: Deidentified data were obtained from 508,969 patients tested for coronavirus disease 2019 (COVID-19) with the TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) in four CLIA-certified clinical laboratories in Puerto Rico (n = 86,639) and in three CLIA-certified clinical laboratories in the United States (n = 422,330). RESULTS: TaqPath data revealed a frequency of S Gene Target Failure (SGTF) > 47% for the last week of March 2021 in both, Puerto Rico and US laboratories. The monthly frequency of SGTF in Puerto Rico steadily increased exponentially from 4% in November 2020 to 47% in March 2021. The weekly SGTF rate in US samples was high (>8%) from late December to early January and then also increased exponentially through April (48%). The exponential increase in SGFT prevalence in Puerto Rico was concurrent with a sharp increase in VOCs among all SARS-CoV-2 sequences from Puerto Rico uploaded to Global Influenza Surveillance and Response System (GISAID) (n = 461). Alpha variant frequency increased from <1% in the last week of January 2021 to 51.5% of viral sequences from Puerto Rico collected in the last week of March 2021. CONCLUSIONS: According to the proposed evidence-based algorithm, approximately 50% of all SGTF patients should be managed with VOCs self-quarantine and contact tracing protocols, while WGS confirms their lineage in genomic surveillance laboratories. Our results suggest this workflow is useful for tracking VOCs with SGTF.


Assuntos
COVID-19 , SARS-CoV-2 , Sequência de Bases , COVID-19/diagnóstico , COVID-19/epidemiologia , Humanos , Medicina de Precisão , SARS-CoV-2/genética , Estados Unidos/epidemiologia
5.
Epigenetics ; 15(9): 959-971, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32164487

RESUMO

Human papillomavirus-related oropharyngeal squamous cell carcinoma (HPV+ OPSCC) represents a unique disease entity within head and neck cancer with rising incidence. Previous work has shown that alternative splicing events (ASEs) are prevalent in HPV+ OPSCC, but further validation is needed to understand the regulation of this process and its role in these tumours. In this study, eleven ASEs (GIT2, CTNNB1, MKNK2, MRPL33, SIPA1L3, SNHG6, SYCP2, TPRG1, ZHX2, ZNF331, and ELOVL1) were selected for validation from 109 previously published candidate ASEs to elucidate the post-transcriptional mechanisms of oncogenesis in HPV+ disease. In vitro qRT-PCR confirmed differential expression of 9 of 11 ASE candidates, and in silico analysis within the TCGA cohort confirmed 8 of 11 candidates. Six ASEs (MRPL33, SIPA1L3, SNHG6, TPRG1, ZHX2, and ELOVL1) showed significant differential expression across both methods. Further evaluation of chromatin modification revealed that ASEs strongly correlated with cancer-specific distribution of acetylated lysine 27 of histone 3 (H3K27ac). Subsequent epigenetic treatment of HPV+ HNSCC cell lines (UM-SCC-047 and UPCI-SCC-090) with JQ1 not only induced downregulation of cancer-specific ASE isoforms, but also growth inhibition in both cell lines. The UPCI-SCC-090 cell line, with greater ASE expression, also showed more significant growth inhibition after JQ1 treatment. This study confirms several novel cancer-specific ASEs in HPV+OPSCC and provides evidence for the role of chromatin modifications in regulation of alternative splicing in HPV+OPSCC. This highlights the role of epigenetic changes in the oncogenesis of HPV+OPSCC, which represents a unique, unexplored target for therapeutics that can alter the global post-transcriptional landscape.


Assuntos
Processamento Alternativo , Carcinoma de Células Escamosas/genética , Montagem e Desmontagem da Cromatina , Regulação Neoplásica da Expressão Gênica , Neoplasias Orofaríngeas/genética , Alphapapillomavirus/patogenicidade , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/virologia , Linhagem Celular Tumoral , Epigênese Genética , Loci Gênicos , Código das Histonas , Histonas/química , Histonas/metabolismo , Humanos , Neoplasias Orofaríngeas/metabolismo , Neoplasias Orofaríngeas/virologia
6.
Transl Res ; 202: 109-119, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30118659

RESUMO

We have recently performed the characterization of alternative splicing events (ASEs) in head and neck squamous cell carcinoma, which allows dysregulation of protein expression common for cancer cells. Such analysis demonstrated a high ASE prevalence among tumor samples, including tumor-specific alternative splicing in the GSN gene.In vitro studies confirmed that overall expression of either ASE-GSN or wild-type GSN (WT-GSN) isoform inversely correlated with cell proliferation, whereas the high ratio of ASE-GSN to WT-GSN correlated with increased cellular invasion. Additionally, a change in expression of either isoform caused compensatory changes in expression of the other isoform. Our results suggest that the overall expression and the balance between GSN isoforms are mediating factors in proliferation, while increased overall expression of ASE-GSN is specific to cancer tissues. As a result, we propose ASE-GSN can serve not only as a biomarker of disease and disease progression, but also as a neoantigen for head and neck squamous cell carcinoma treatment, for which only a limited number of disease-specific targeted therapies currently exist.


Assuntos
Gelsolina/genética , Processamento Alternativo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Gelsolina/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Modelos Biológicos , Invasividade Neoplásica , Metástase Neoplásica , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
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