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1.
Exp Biol Med (Maywood) ; 249: 10161, 2024.
Article de Anglais | MEDLINE | ID: mdl-38966281

RÉSUMÉ

Osteosarcoma is a form of bone cancer that predominantly impacts osteoblasts, the cells responsible for creating fresh bone tissue. Typical indications include bone pain, inflammation, sensitivity, mobility constraints, and fractures. Utilising imaging techniques such as X-rays, MRI scans, and CT scans can provide insights into the size and location of the tumour. Additionally, a biopsy is employed to confirm the diagnosis. Analysing genes with distinct expression patterns unique to osteosarcoma can be valuable for early detection and the development of effective treatment approaches. In this research, we comprehensively examined the entire transcriptome and pinpointed genes with altered expression profiles specific to osteosarcoma. The study mainly aimed to identify the molecular fingerprint of osteosarcoma. In this study, we processed 90 FFPE samples from PathWest with an almost equal number of osteosarcoma and healthy tissues. RNA was extracted from Paraffin-embedded tissue; RNA was sequenced, the sequencing data was analysed, and gene expression was compared to the healthy samples of the same patients. Differentially expressed genes in osteosarcoma-derived samples were identified, and the functions of those genes were explored. This result was combined with our previous studies based on FFPE and fresh samples to perform a meta-analysis. We identified 1,500 identical differentially expressed genes in PathWest osteosarcoma samples compared to normal tissue samples of the same patients. Meta-analysis with combined fresh tissue samples identified 530 differentially expressed genes. IFITM5, MMP13, PANX3, and MAGEA6 were some of the most overexpressed genes in osteosarcoma samples, while SLC4A1, HBA1, HBB, AQP7 genes were some of the top downregulated genes. Through the meta-analysis, 530 differentially expressed genes were identified to be identical among FFPE (105 FFPE samples) and 36 fresh bone samples. Deconvolution analysis with single-cell RNAseq data confirmed the presence of specific cell clusters in FFPE samples. We propose these 530 DEGs as a molecular fingerprint of osteosarcoma.


Sujet(s)
Tumeurs osseuses , Analyse de profil d'expression de gènes , Ostéosarcome , Ostéosarcome/génétique , Ostéosarcome/anatomopathologie , Humains , Analyse de profil d'expression de gènes/méthodes , Tumeurs osseuses/génétique , Tumeurs osseuses/anatomopathologie , Tumeurs osseuses/métabolisme , Inclusion en paraffine , Transcriptome/génétique , Régulation de l'expression des gènes tumoraux , Fixation tissulaire , Formaldéhyde
2.
Methods Mol Biol ; 2825: 173-184, 2024.
Article de Anglais | MEDLINE | ID: mdl-38913309

RÉSUMÉ

Multitarget fluorescence in situ hybridization (mFISH) is a technique that allows the detection of multiple target sequences on the same sample using spectrally distinct fluorophore labels. The mFISH approach is currently a useful assay in the oncologic field for the detection of predictive, prognostic, and diagnostic biomarkers. In this chapter, we summarize the application of mFISH in the identification of target genetic aberrations in formalin-fixed, paraffin-embedded (FFPE) tissue samples of several tumor types. We discuss the mFISH protocols in FFPE samples, the innovative multitarget probes used, and the critical issues related to their interpretation.


Sujet(s)
Hybridation fluorescente in situ , Tumeurs , Inclusion en paraffine , Hybridation fluorescente in situ/méthodes , Humains , Tumeurs/génétique , Tumeurs/diagnostic , Inclusion en paraffine/méthodes , Fixation tissulaire/méthodes , Marqueurs biologiques tumoraux/génétique , Formaldéhyde/composition chimique
3.
Biochemistry (Mosc) ; 89(4): 637-652, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38831501

RÉSUMÉ

Molecular genetic analysis of tumor tissues is the most important step towards understanding the mechanisms of cancer development; it is also necessary for the choice of targeted therapy. The Hi-C (high-throughput chromatin conformation capture) technology can be used to detect various types of genomic variants, including balanced chromosomal rearrangements, such as inversions and translocations. We propose a modification of the Hi-C method for the analysis of chromatin contacts in formalin-fixed paraffin-embedded (FFPE) sections of tumor tissues. The developed protocol allows to generate high-quality Hi-C data and detect all types of chromosomal rearrangements. We have analyzed various databases to compile a comprehensive list of translocations that hold clinical importance for the targeted therapy selection. The practical value of molecular genetic testing is its ability to influence the treatment strategies and to provide prognostic insights. Detecting specific chromosomal rearrangements can guide the choice of the targeted therapies, which is a critical aspect of personalized medicine in oncology.


Sujet(s)
Formaldéhyde , Tumeurs , Inclusion en paraffine , Humains , Tumeurs/génétique , Tumeurs/anatomopathologie , Formaldéhyde/composition chimique , Translocation génétique , Fixation tissulaire , Chromatine/génétique , Chromatine/métabolisme , Chromatine/composition chimique
4.
Commun Biol ; 7(1): 708, 2024 Jun 08.
Article de Anglais | MEDLINE | ID: mdl-38851810

RÉSUMÉ

Robotically assisted proteomics provides insights into the regulation of multiple proteins achieving excellent spatial resolution. However, developing an effective method for spatially resolved quantitative proteomics of formalin fixed paraffin embedded tissue (FFPE) in an accessible and economical manner remains challenging. We introduce non-robotic In-insert FFPE proteomics approach, combining glass insert FFPE tissue processing with spatial quantitative data-independent mass spectrometry (DIA). In-insert approach identifies 450 proteins from a 5 µm thick breast FFPE tissue voxel with 50 µm lateral dimensions covering several tens of cells. Furthermore, In-insert approach associated a keratin series and moesin (MOES) with prolactin-induced protein (PIP) indicating their prolactin and/or estrogen regulation. Our data suggest that PIP is a spatial biomarker for hormonally triggered cytoskeletal remodeling, potentially useful for screening hormonally affected hotspots in breast tissue. In-insert proteomics represents an alternative FFPE processing method, requiring minimal laboratory equipment and skills to generate spatial proteotype repositories from FFPE tissue.


Sujet(s)
Marqueurs biologiques , Cytosquelette , Inclusion en paraffine , Protéomique , Fixation tissulaire , Humains , Protéomique/méthodes , Cytosquelette/métabolisme , Femelle , Marqueurs biologiques/métabolisme , Fixation tissulaire/méthodes , Prolactine/métabolisme , Formaldéhyde/pharmacologie , Protéines et peptides de signalisation intracellulaire/métabolisme , Protéines des microfilaments/métabolisme , Protéines de transport membranaire
5.
Curr Protoc ; 4(6): e1093, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38923415

RÉSUMÉ

Fluorescence in situ hybridization (FISH) is a cytogenetic assay that is widely used in both clinical and research settings to validate genetic aberrations. Simple in principle, it is based on denaturation and hybridization of a DNA probe and its complementary sequence; however, it is subject to continuous optimization. Here we share how in-house FISH can be optimized using different control tissues to visualize and ultimately validate common and novel genetic abnormalities unearthed by next-generation sequencing (NGS). Seven specific FISH probes were designed and labeled, and conditions for eight tissue types and one patient-derived tumor organoid were optimized. Formalin-fixed paraffin-embedded (FFPE) tissue slides were used for each experiment. Slides were first deparaffinized, then placed in a pretreatment solution followed by a digestion step. In-house FISH probes were then added to the tissue to be denatured and hybridized, and then washed twice. To obtain optimal results, probe concentration, pepsin incubation time, denaturation, and the two post-hybridization washes were optimized for each sample. By modifying the above conditions, all FISH experiments were optimized in separate tissue types to investigate specific genomic alterations in tumors arising in those tissues. Signals were clear and distinct, allowing for visualization of the selected probes. Following this protocol, our lab has quickly optimized 11 directly labeled in-house FISH probes to support genetic aberrations nominated by NGS, including most recent discoveries through whole-genome sequencing analyses. We describe a robust approach of how to advance in-house labeled FISH probes. By following these guidelines, reliable and reproducible FISH results can be obtained to interrogate FFPE slides from benign, tumor tissues, and patient-derived tumor organoid specimens. This is of most relevance in the era of NGS and precision oncology. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Metaphase FISH optimization Support Protocol 1: In-house probe labeling and preparation Support Protocol 2: Metaphase spread preparation Basic Protocol 2: Optimization of FISH on formalin-fixed paraffin-embedded tissue.


Sujet(s)
Hybridation fluorescente in situ , Médecine de précision , Hybridation fluorescente in situ/méthodes , Humains , Médecine de précision/méthodes , Inclusion en paraffine , Tumeurs/génétique , Tumeurs/diagnostic , Séquençage nucléotidique à haut débit/méthodes , Sondes d'ADN/génétique
6.
Sci Rep ; 14(1): 12688, 2024 06 03.
Article de Anglais | MEDLINE | ID: mdl-38830987

RÉSUMÉ

Comprehensive characterization of protein networks in mounted brain tissue represents a major challenge in brain and neurodegenerative disease research. In this study, we develop a simple staining method, called TSWIFT, to iteratively stain pre-mounted formalin fixed, paraffin embedded (FFPE) brain sections, thus enabling high-dimensional sample phenotyping. We show that TSWIFT conserves tissue architecture and allows for relabeling a single mounted FFPE sample more than 10 times, even after prolonged storage at 4 °C. Our results establish TSWIFT as an efficient method to obtain integrated high-dimensional knowledge of cellular proteomes by analyzing mounted FFPE human brain tissue.


Sujet(s)
Encéphale , Inclusion en paraffine , Coloration et marquage , Humains , Encéphale/métabolisme , Inclusion en paraffine/méthodes , Coloration et marquage/méthodes , Fixation tissulaire/méthodes , Protéome/analyse , Formaldéhyde/composition chimique , Protéomique/méthodes
7.
Sci Rep ; 14(1): 13699, 2024 06 13.
Article de Anglais | MEDLINE | ID: mdl-38871991

RÉSUMÉ

The detection of copy number variations (CNVs) and somatic mutations in cancer is important for the selection of specific drugs for patients with cancer. In cancers with sporadic tumor cells, low tumor content prevents the accurate detection of somatic alterations using targeted sequencing. To efficiently identify CNVs, we performed tumor cell enrichment using tissue suspensions of formalin-fixed paraffin-embedded (FFPE) tissue sections with low tumor cell content. Tumor-enriched and residual fractions were separated from FFPE tissue suspensions of intestinal and diffuse-type gastric cancers containing sporadic tumor cells, and targeted sequencing was performed on 225 cancer-related genes. Sequencing of a targeted panel of cancer-related genes using tumor-enriched fractions increased the number of detectable CNVs and the copy number of amplified genes. Furthermore, CNV analysis using the normal cell-enriched residual fraction as a reference for CNV scoring allowed targeted sequencing to detect CNV characteristics of diffuse-type gastric cancer with low tumor content. Our approach improves the CNV detection rate in targeted sequencing with tumor enrichment and the accuracy of CNV detection in archival samples without paired blood.


Sujet(s)
Variations de nombre de copies de segment d'ADN , Tumeurs de l'estomac , Humains , Tumeurs de l'estomac/génétique , Tumeurs de l'estomac/anatomopathologie , Inclusion en paraffine/méthodes , Mâle , Femelle , Séquençage nucléotidique à haut débit/méthodes , Sujet âgé , Mutation
8.
J Proteome Res ; 23(7): 2542-2551, 2024 Jul 05.
Article de Anglais | MEDLINE | ID: mdl-38869849

RÉSUMÉ

The application of innovative spatial proteomics techniques, such as those based upon matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) technology, has the potential to impact research in the field of nephropathology. Notwithstanding, the possibility to apply this technology in more routine diagnostic contexts remains limited by the alternative fixatives employed by this ultraspecialized diagnostic field, where most nephropathology laboratories worldwide use bouin-fixed paraffin-embedded (BFPE) samples. Here, the feasibility of performing MALDI-MSI on BFPE renal tissue is explored, evaluating variability within the trypsin-digested proteome as a result of different preanalytical conditions and comparing them with the more standardized formalin-fixed paraffin-embedded (FFPE) counterparts. A large proportion of the features (270, 68.9%) was detected in both BFPE and FFPE renal samples, demonstrating only limited variability in signal intensity (10.22-10.06%). Samples processed with either fixative were able to discriminate the principal parenchyma regions along with diverse renal substructures, such as glomeruli, tubules, and vessels. This was observed when performing an additional "stress test", showing comparable results in both BFPE and FFPE samples when the distribution of several amyloid fingerprint proteins was mapped. These results suggest the utility of BFPE tissue specimens in MSI-based nephropathology research, further widening their application in this field.


Sujet(s)
Études de faisabilité , Formaldéhyde , Rein , Inclusion en paraffine , Protéomique , Spectrométrie de masse MALDI , Fixation tissulaire , Spectrométrie de masse MALDI/méthodes , Protéomique/méthodes , Humains , Rein/composition chimique , Rein/anatomopathologie , Rein/métabolisme , Formaldéhyde/composition chimique , Maladies du rein/anatomopathologie , Maladies du rein/métabolisme , Maladies du rein/diagnostic , Fixateurs/composition chimique , Protéome/analyse
9.
J Clin Exp Hematop ; 64(2): 138-143, 2024.
Article de Anglais | MEDLINE | ID: mdl-38925974

RÉSUMÉ

In the new WHO classifications of haematolymphoid tumours (WHO-HAEM5), classic Hodgkin lymphoma (cHL) is categorized into B-cell lymphoid proliferations and lymphomas. Although the majority of Hodgkin Reed-Sternberg (HRS) cells are of germinal center B-cell origin with some defects of B-cell transcription factors, they rarely express T-cell antigens or cytotoxic molecules. Clonality analyses on cHL samples using BIOMED-2 have been reported by several groups; however, those studies were only focused on Ig regions, including IgH, Ig-kappa, and Ig-lambda, and TCR-γ clonality analysis of cHL has not yet been explored. Here, we investigated TCR-γ gene rearrangement for one hundred cases using a PCR-based method. Four of one hundred (4%) cases showed TCR-γ clonal peaks. Of these, three were at an advanced stage and one patient died of the disease. To clarify whether HRS cells showed T-cell clonality or not, we performed PCR analysis using DNAs of microdissected HRS cells. Three samples showed identical clonal peaks with bulk specimens. Our results indicate that cHL is a heterogeneous disease of mainly B-cell and rarely T-cell origin with a special phenotype. Further molecular studies are warranted.


Sujet(s)
Maladie de Hodgkin , Humains , Maladie de Hodgkin/génétique , Maladie de Hodgkin/diagnostic , Mâle , Adulte , Femelle , Adulte d'âge moyen , Sujet âgé , Réarrangement des gènes de la chaine gamma du récepteur pour l'antigène des cellules T , Inclusion en paraffine , Sujet âgé de 80 ans ou plus , Adolescent , Récepteur lymphocytaire T antigène, gamma-delta/génétique , Cellules de Reed-Sternberg/anatomopathologie , Cellules de Reed-Sternberg/métabolisme , Jeune adulte , Réaction de polymérisation en chaîne
10.
Methods Cell Biol ; 186: 25-49, 2024.
Article de Anglais | MEDLINE | ID: mdl-38705603

RÉSUMÉ

One of the earliest applications of flow cytometry was the measurement of DNA content in cells. This method is based on the ability to stain DNA in a stoichiometric manner (i.e., the amount of stain is directly proportional to the amount of DNA within the cell). For more than 40years, a number of studies have consistently demonstrated the utility of DNA flow cytometry as a potential diagnostic and/or prognostic tool in patients with most epithelial tumors, including pre-invasive lesions (such as dysplasia) in the gastrointestinal tract. However, its availability as a clinical test has been limited to few medical centers due to the requirement for fresh tissue in earlier studies and perceived technical demands. However, more recent studies have successfully utilized formalin-fixed paraffin-embedded (FFPE) tissue to generate high-quality DNA content histograms, demonstrating the feasibility of this methodology. This review summarizes step-by-step methods on how to perform DNA flow cytometry using FFPE tissue and analyze DNA content histograms based on the published consensus guidelines in order to assist in the diagnosis and/or risk stratification of many different epithelial tumors, with particular emphasis on dysplasia associated with Barrett's esophagus and inflammatory bowel disease.


Sujet(s)
Cytométrie en flux , Tumeurs gastro-intestinales , Instabilité du génome , Humains , Cytométrie en flux/méthodes , Tumeurs gastro-intestinales/génétique , Tumeurs gastro-intestinales/diagnostic , Tumeurs gastro-intestinales/anatomopathologie , Instabilité du génome/génétique , États précancéreux/génétique , États précancéreux/diagnostic , États précancéreux/anatomopathologie , Fixation tissulaire/méthodes , Inclusion en paraffine/méthodes , ADN/génétique , ADN/analyse , Tube digestif/anatomopathologie , Tube digestif/métabolisme , Oesophage de Barrett/génétique , Oesophage de Barrett/anatomopathologie , Oesophage de Barrett/diagnostic
11.
J Vis Exp ; (207)2024 May 03.
Article de Anglais | MEDLINE | ID: mdl-38767376

RÉSUMÉ

Understanding the relationship between the cells and their location within each tissue is critical to uncover the biological processes associated with normal development and disease pathology. Spatial transcriptomics is a powerful method that enables the analysis of the whole transcriptome within tissue samples, thus providing information about the cellular gene expression and the histological context in which the cells reside. While this method has been extensively utilized for many soft tissues, its application for the analyses of hard tissues such as bone has been challenging. The major challenge resides in the inability to preserve good quality RNA and tissue morphology while processing the hard tissue samples for sectioning. Therefore, a method is described here to process freshly obtained bone tissue samples to effectively generate spatial transcriptomics data. The method allows for the decalcification of the samples, granting successful tissue sections with preserved morphological details while avoiding RNA degradation. In addition, detailed guidelines are provided for samples that were previously paraffin-embedded, without demineralization, such as samples collected from tissue banks. Using these guidelines, high-quality spatial transcriptomics data generated from tissue bank samples of primary tumor and lung metastasis of bone osteosarcoma are shown.


Sujet(s)
Tumeurs osseuses , Os et tissu osseux , Transcriptome , Humains , Transcriptome/génétique , Os et tissu osseux/métabolisme , Tumeurs osseuses/génétique , Tumeurs osseuses/anatomopathologie , Tumeurs osseuses/métabolisme , Ostéosarcome/génétique , Ostéosarcome/anatomopathologie , Ostéosarcome/métabolisme , Analyse de profil d'expression de gènes/méthodes , Inclusion en paraffine/méthodes , Tumeurs du poumon/génétique , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/métabolisme
12.
Anat Histol Embryol ; 53(3): e13046, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38712731

RÉSUMÉ

The present study aims to evaluate the morphometric and histopathological properties of Modified Elnady's plastinated tissue after a period compared to non-plastinated tissue. The plastination technique is utilized in research and teaching due to the potential health risks associated with prolonged exposure to formalin. The tissues and organs are permanently dried during plastination and can be used for further anatomical, histopathological and surgical educational purposes. This method involves drying tissue and allowing synthetic materials like glycerin to permeate it. The study compared non-plastinated and plastinated tissue post-plastination to determine if structural alterations differed from those linked to plastination. The study examined the histopathological examination of dogs' skin, muscles, liver, lung, and intestine using formalin-fixed organs for paraffin embedding and previously plastinated organs for a plastinated group. The study examined non-plastinated and plastinated tissues, their histological composition and biometric parameters revealing typical structures in the non-plastinated group. Plasmodiumted tissues exhibited a compacted appearance, volume changes, nuclear clarity, and cytoplasmic hypereosinophilia, with statistical differences between the two groups. The study reveals that plastinated tissues, after 5 years of plastination, maintain their histological architecture well, with some exceptions. Plastinated tissues can be utilized in future microscopic and immunological studies and will be beneficial for teaching and research.


Sujet(s)
Foie , Poumon , Plastination , Animaux , Chiens , Plastination/méthodes , Poumon/anatomopathologie , Foie/anatomopathologie , Peau/anatomopathologie , Peau/anatomie et histologie , Intestins/anatomie et histologie , Intestins/anatomopathologie , Inclusion en paraffine/médecine vétérinaire , Formaldéhyde , Anatomie vétérinaire/enseignement et éducation
13.
Elife ; 132024 May 22.
Article de Anglais | MEDLINE | ID: mdl-38775133

RÉSUMÉ

Tissue-clearing and labeling techniques have revolutionized brain-wide imaging and analysis, yet their application to clinical formalin-fixed paraffin-embedded (FFPE) blocks remains challenging. We introduce HIF-Clear, a novel method for efficiently clearing and labeling centimeter-thick FFPE specimens using elevated temperature and concentrated detergents. HIF-Clear with multi-round immunolabeling reveals neuron circuitry regulating multiple neurotransmitter systems in a whole FFPE mouse brain and is able to be used as the evaluation of disease treatment efficiency. HIF-Clear also supports expansion microscopy and can be performed on a non-sectioned 15-year-old FFPE specimen, as well as a 3-month formalin-fixed mouse brain. Thus, HIF-Clear represents a feasible approach for researching archived FFPE specimens for future neuroscientific and 3D neuropathological analyses.


Sujet(s)
Encéphale , Formaldéhyde , Neurones , Inclusion en paraffine , Fixation tissulaire , Animaux , Inclusion en paraffine/méthodes , Souris , Fixation tissulaire/méthodes , Neurones/physiologie , Fixateurs/composition chimique
14.
PLoS One ; 19(5): e0304411, 2024.
Article de Anglais | MEDLINE | ID: mdl-38809937

RÉSUMÉ

Next-generation sequencing (NGS) has been increasingly popular in genomics studies over the last decade and is now commonly used in clinical applications for precision diagnostics. Many disease areas typically involve different kinds of sample specimens, sample qualities and quantities. The quality of the DNA can range from intact, high molecular weight molecules to degraded, damaged and very short molecules. The differences in quality and quantity pose challenges for downstream molecular analyses. To overcome the challenge with the need of different molecular methods for different types of samples, we have developed a joint procedure for preparing enriched DNA libraries from high molecular weight DNA and DNA from formalin-fixed, paraffin-embedded tissue, fresh frozen tissue material, as well as cell-free DNA.


Sujet(s)
Séquençage nucléotidique à haut débit , Séquençage nucléotidique à haut débit/méthodes , Humains , ADN/génétique , Banque de gènes , Analyse de séquence d'ADN/méthodes , Inclusion en paraffine/méthodes
15.
J Med Virol ; 96(6): e29716, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38818787

RÉSUMÉ

Accumulating evidence has demonstrated that high-risk human papillomaviruses (HR-HPVs) are involved in the etiology of a subset of oropharyngeal squamous cell carcinoma (OPSCC). In this regard, the International Agency for Research on Cancer (IARC) has recommended direct molecular HPV testing. So far, there is no agreement on the most appropriate method for HPV detection on OPSCC formalin-fixed paraffin-embedded (FFPE) materials. In this study, we aimed to evaluate the performance of the high-sensitive SureX HPV assay in OPSCC FFPE tissues compared with LiPA-25 and p16ink4a immunostaining. A retrospective series of FFPE primary OPSCC cases were diagnosed between 2008 and 2019 and provided by the Henan Cancer Hospital, China. The level of agreement of two assays was determined using Cohen's Kappa (κ) statistics. A total of 230 FFPE OPSCC samples from tumor resections (n = 160) and diagnostic biopsies (n = 70) were detected. Sixty-six (28.7%) and 70 (30.4%) samples were identified as HPV-DNA-positive by LiPA-25 and SureX, respectively, of which HPV16 was largely the most common type (95.5% vs 94.3%). We found a perfect concordance between LiPA-25 and SureX for HPV-DNA status (κ = 0.906, 95% CI: 0.875-0.937) and for HPV16 (κ = 0.925, 95% CI: 0.897-0.953). In addition, SureX and p16ink4a immunostaining had a perfect concordance (κ = 0.917, 95% CI: 0.888-0.946). Moreover, the HPV-driven fraction, based on double positivity for HPV-DNA and p16ink4a, was similar between SureX (63 of 230, 27.4%) and LiPA-25 (60 of 230, 26.1%). Similar results were found in samples from resections and biopsies. SureX and LiPA-25 are comparable. SureX could be used for routine HPV-DNA detection and genotyping on archival OPSCC FFPE tissues.


Sujet(s)
ADN viral , Génotype , Protéines des oncogènes viraux , Tumeurs de l'oropharynx , Infections à papillomavirus , Inclusion en paraffine , Humains , Tumeurs de l'oropharynx/virologie , Études rétrospectives , Infections à papillomavirus/virologie , Infections à papillomavirus/diagnostic , Adulte d'âge moyen , Mâle , Femelle , Protéines des oncogènes viraux/génétique , Sujet âgé , ADN viral/génétique , Papillomaviridae/génétique , Papillomaviridae/isolement et purification , Papillomaviridae/classification , Réaction de polymérisation en chaîne/méthodes , Techniques de génotypage/méthodes , Chine , Adulte , Formaldéhyde , Virus des Papillomavirus humains
16.
Curr Oncol ; 31(5): 2441-2452, 2024 04 28.
Article de Anglais | MEDLINE | ID: mdl-38785464

RÉSUMÉ

Personalized cancer care requires molecular characterization of neoplasms. While the research community accepts frozen tissues as the gold standard analyte for molecular assays, the source of tissue for testing in clinical cancer care comes almost universally from formalin-fixed, paraffin-embedded tissue (FFPE). As newer technologies emerge for DNA characterization that requires higher molecular weight DNA, it was necessary to compare the quality of DNA in terms of DNA length between FFPE and cryopreserved samples. We hypothesized that cryopreserved samples would yield higher quantity and superior quality DNA compared to FFPE samples. We analyzed DNA metrics by performing a head-to-head comparison between FFPE and cryopreserved samples from 38 human tumors representing various cancer types. DNA quantity and purity were measured by UV spectrophotometry, and DNA from cryopreserved tissue demonstrated a 4.2-fold increase in DNA yield per mg of tissue (p-value < 0.001). DNA quality was measured on a fragment microelectrophoresis analyzer, and again, DNA from cryopreserved tissue demonstrated a 223% increase in the DNA quality number and a 9-fold increase in DNA fragments > 40,000 bp (p-value < 0.0001). DNA from the cryopreserved tissues was superior to the DNA from FFPE samples in terms of DNA yield and quality.


Sujet(s)
Cryoconservation , Tumeurs , Inclusion en paraffine , Humains , Cryoconservation/méthodes , Inclusion en paraffine/méthodes , Tumeurs/génétique , Fixation tissulaire/méthodes , ADN/analyse , Formaldéhyde , ADN tumoral/analyse
17.
PLoS One ; 19(5): e0299557, 2024.
Article de Anglais | MEDLINE | ID: mdl-38718072

RÉSUMÉ

The continued development in methylome analysis has enabled a more precise assessment of DNA methylation, but treatment of target tissue prior to analysis may affect DNA analysis. Prediction of age based on methylation levels in the genome (DNAmAge) has gained much interest in disease predisposition (biological age estimation), but also in chronological donor age estimation in crime case samples. Various epigenetic clocks were designed to predict the age. However, it remains unknown how the storage of the tissues affects the DNAmAge estimation. In this study, we investigated the storage method impact of DNAmAge by the comparing the DNAmAge of the two commonly used storage methods, freezing and formalin-fixation and paraffin-embedding (FFPE) to DNAmAge of fresh tissue. This was carried out by comparing paired heart tissue samples of fresh tissue, samples stored by freezing and FFPE to chronological age and whole blood samples from the same individuals. Illumina EPIC beadchip array was used for methylation analysis and the DNAmAge was evaluated with the following epigenetic clocks: Horvath, Hannum, Levine, Horvath skin+blood clock (Horvath2), PedBE, Wu, BLUP, EN, and TL. We observed differences in DNAmAge among the storage conditions. FFPE samples showed a lower DNAmAge compared to that of frozen and fresh samples. Additionally, the DNAmAge of the heart tissue was lower than that of the whole blood and the chronological age. This highlights caution when evaluating DNAmAge for FFPE samples as the results were underestimated compared with fresh and frozen tissue samples. Furthermore, the study also emphasizes the need for a DNAmAge model based on heart tissue samples for an accurate age estimation.


Sujet(s)
Méthylation de l'ADN , Formaldéhyde , Myocarde , Inclusion en paraffine , Fixation tissulaire , Humains , Inclusion en paraffine/méthodes , Formaldéhyde/composition chimique , Myocarde/métabolisme , Fixation tissulaire/méthodes , Mâle , Adulte , Femelle , Adulte d'âge moyen , Cryoconservation/méthodes , Adolescent , Sujet âgé , Jeune adulte
18.
Life Sci Alliance ; 7(8)2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38782602

RÉSUMÉ

Consensus Molecular Subtype (CMS) classification of colorectal cancer (CRC) tissues is complicated by RNA degradation upon formalin-fixed paraffin-embedded (FFPE) preservation. Here, we present an FFPE-curated CMS classifier. The CMSFFPE classifier was developed using genes with a high transcript integrity in FFPE-derived RNA. We evaluated the classification accuracy in two FFPE-RNA datasets with matched fresh-frozen (FF) RNA data, and an FF-derived RNA set. An FFPE-RNA application cohort of metastatic CRC patients was established, partly treated with anti-EGFR therapy. Key characteristics per CMS were assessed. Cross-referenced with matched benchmark FF CMS calls, the CMSFFPE classifier strongly improved classification accuracy in two FFPE datasets compared with the original CMSClassifier (63.6% versus 40.9% and 83.3% versus 66.7%, respectively). We recovered CMS-specific recurrence-free survival patterns (CMS4 versus CMS2: hazard ratio 1.75, 95% CI 1.24-2.46). Key molecular and clinical associations of the CMSs were confirmed. In particular, we demonstrated the predictive value of CMS2 and CMS3 for anti-EGFR therapy response (CMS2&3: odds ratio 5.48, 95% CI 1.10-27.27). The CMSFFPE classifier is an optimized FFPE-curated research tool for CMS classification of clinical CRC samples.


Sujet(s)
Tumeurs colorectales , Humains , Tumeurs colorectales/génétique , Tumeurs colorectales/classification , Tumeurs colorectales/anatomopathologie , Inclusion en paraffine , Marqueurs biologiques tumoraux/génétique , Récepteurs ErbB/génétique , Récepteurs ErbB/métabolisme , Femelle , Consensus , Fixation tissulaire/méthodes , Mâle , Analyse de profil d'expression de gènes/méthodes , Sujet âgé , Adulte d'âge moyen , Pronostic , Régulation de l'expression des gènes tumoraux , Formaldéhyde
19.
Exp Mol Pathol ; 137: 104906, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38820761

RÉSUMÉ

BACKGROUND: Shallow whole genome sequencing (Shallow-seq) is used to determine the copy number aberrations (CNA) in tissue samples and circulating tumor DNA. However, costs of NGS and challenges of small biopsies ask for an alternative to the untargeted NGS approaches. The mFAST-SeqS approach, relying on LINE-1 repeat amplification, showed a good correlation with Shallow-seq to detect CNA in blood samples. In the present study, we evaluated whether mFAST-SeqS is suitable to assess CNA in small formalin-fixed paraffin-embedded (FFPE) tissue specimens, using vulva and anal HPV-related lesions. METHODS: Seventy-two FFPE samples, including 36 control samples (19 vulva;17 anal) for threshold setting and 36 samples (24 vulva; 12 anal) for clinical evaluation, were analyzed by mFAST-SeqS. CNA in vulva and anal lesions were determined by calculating genome-wide and chromosome arm-specific z-scores in comparison with the respective control samples. Sixteen samples were also analyzed with the conventional Shallow-seq approach. RESULTS: Genome-wide z-scores increased with the severity of disease, with highest values being found in cancers. In vulva samples median and inter quartile ranges [IQR] were 1[0-2] in normal tissues (n = 4), 3[1-7] in premalignant lesions (n = 9) and 21[13-48] in cancers (n = 10). In anal samples, median [IQR] were 0[0-1] in normal tissues (n = 4), 14[6-38] in premalignant lesions (n = 4) and 18[9-31] in cancers (n = 4). At threshold 4, all controls were CNA negative, while 8/13 premalignant lesions and 12/14 cancers were CNA positive. CNA captured by mFAST-SeqS were mostly also found by Shallow-seq. CONCLUSION: mFAST-SeqS is easy to perform, requires less DNA and less sequencing reads reducing costs, thereby providing a good alternative for Shallow-seq to determine CNA in small FFPE samples.


Sujet(s)
Variations de nombre de copies de segment d'ADN , Inclusion en paraffine , Humains , Femelle , Variations de nombre de copies de segment d'ADN/génétique , Inclusion en paraffine/méthodes , Séquençage nucléotidique à haut débit/méthodes , Formaldéhyde , Fixation tissulaire/méthodes , Séquençage du génome entier/méthodes , Tumeurs de la vulve/génétique , Tumeurs de la vulve/anatomopathologie , Infections à papillomavirus/génétique , Infections à papillomavirus/virologie , Infections à papillomavirus/diagnostic , Tumeurs de l'anus/génétique , Tumeurs de l'anus/diagnostic
20.
Int J Exp Pathol ; 105(3): 90-99, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38717047

RÉSUMÉ

Management of lung cancer today obligates a mutational analysis of the epidermal growth factor receptor (EGFR) gene particularly when Tyrosine Kinase Inhibitor (TKI) therapy is being considered as part of prognostic stratification. This study evaluates the performance of automated microfluidics-based EGFR mutation detection and its significance in clinical diagnostic settings. Formalin-fixed, paraffin-embedded (FFPE) samples from NSCLC patients (n = 174) were included in a two-phase study. Phase I: Validation of the platform by comparing the results with conventional real-time PCR and next-generation sequencing (NGS) platform. Phase II: EGFR mutation detection on microfluidics-based platform as part of routine diagnostics workup. The microfluidics-based platform demonstrates 96.5% and 89.2% concordance with conventional real-time PCR and NGS, respectively. The system efficiently detects mutations across the EGFR gene with 88.23% sensitivity and 100% specificity. Out of 144 samples analysed in phase II, the platform generated valid results in 94% with mutation detected in 41% of samples. This microfluidics-based platform can detect as low as 5% mutant allele fractions from the FFPE samples. Therefore the microfluidics-based platform is a rapid, complete walkaway, with minimum tissue requirement (two sections of 5 µ thickness) and technical skill requirement. The method can detect clinically actionable EGFR mutations efficiently and can be considered a reliable diagnostic platform in resource-limited settings. From receiving samples to reporting the results this platform provides accurate data without much manual intervention. The study helped to devise an algorithm that emphasizes effective screening of the NSCLC cases for EGFR mutations with varying tumour content. Thus it helps in triaging the cases judiciously before proceeding with multigene testing.


Sujet(s)
Carcinome pulmonaire non à petites cellules , Récepteurs ErbB , Séquençage nucléotidique à haut débit , Tumeurs du poumon , Mutation , Humains , Récepteurs ErbB/génétique , Tumeurs du poumon/génétique , Tumeurs du poumon/anatomopathologie , Carcinome pulmonaire non à petites cellules/génétique , Analyse de mutations d'ADN/méthodes , Séquençage nucléotidique à haut débit/méthodes , Microfluidique/méthodes , Réaction de polymérisation en chaine en temps réel/méthodes , Techniques d'analyse microfluidique/méthodes , Inclusion en paraffine
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