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1.
Anal Bioanal Chem ; 413(3): 911-922, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33242117

RESUMEN

Biofluids, such as blood plasma or serum, are currently being evaluated for cancer detection using vibrational spectroscopy. These fluids contain information of key biomolecules, such as proteins, lipids, carbohydrates and nucleic acids, that comprise spectrochemical patterns to differentiate samples. Raman is a water-free and practically non-destructive vibrational spectroscopy technique, capable of recording spectrochemical fingerprints of biofluids with minimum or no sample preparation. Herein, we compare the performance of these two common biofluids (blood plasma and serum) together with ascitic fluid, towards ovarian cancer detection using Raman microspectroscopy. Samples from thirty-eight patients were analysed (n = 18 ovarian cancer patients, n = 20 benign controls) through different spectral pre-processing and discriminant analysis techniques. Ascitic fluid provided the best class separation in both unsupervised and supervised discrimination approaches, where classification accuracies, sensitivities and specificities above 80% were obtained, in comparison to 60-73% with plasma or serum. Ascitic fluid appears to be rich in collagen information responsible for distinguishing ovarian cancer samples, where collagen-signalling bands at 1004 cm-1 (phenylalanine), 1334 cm-1 (CH3CH2 wagging vibration), 1448 cm-1 (CH2 deformation) and 1657 cm-1 (Amide I) exhibited high statistical significance for class differentiation (P < 0.001). The efficacy of vibrational spectroscopy, in particular Raman spectroscopy, combined with ascitic fluid analysis, suggests a potential diagnostic method for ovarian cancer. Raman microspectroscopy analysis of ascitic fluid allows for discrimination of patients with benign gynaecological conditions or ovarian cancer.


Asunto(s)
Líquido Ascítico/química , Neoplasias Ováricas/sangre , Neoplasias Ováricas/diagnóstico , Espectrometría Raman/métodos , Adulto , Anciano , Algoritmos , Estudios de Casos y Controles , Análisis Discriminante , Femenino , Humanos , Persona de Mediana Edad , Plasma , Análisis de Componente Principal , Sensibilidad y Especificidad , Suero , Máquina de Vectores de Soporte
2.
Anal Bioanal Chem ; 412(17): 4077-4087, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32333079

RESUMEN

Raman spectroscopy is a fast and sensitive technique able to identify molecular changes in biological specimens. Herein, we report on three cases where Raman microspectroscopy was used to distinguish normal vs. oesophageal adenocarcinoma (OAC) (case 1) and Barrett's oesophagus vs. OAC (cases 2 and 3) in a non-destructive and highly accurate fashion. Normal and OAC tissues were discriminated using principal component analysis plus linear discriminant analysis (PCA-LDA) with 97% accuracy (94% sensitivity and 100% specificity) (case 1); Barrett's oesophagus vs. OAC tissues were discriminated with accuracies ranging from 98 to 100% (97-100% sensitivity and 100% specificity). Spectral markers responsible for class differentiation were obtained through the difference-between-mean spectrum for each group and the PCA loadings, where C-O-C skeletal mode in ß-glucose (900 cm-1), lipids (967 cm-1), phosphodioxy (1296 cm-1), deoxyribose (1456 cm-1) and collagen (1445, 1665 cm-1) were associated with normal and OAC tissue differences. Phenylalanine (1003 cm-1), proline/collagen (1066, 1445 cm-1), phospholipids (1130 cm-1), CH2 angular deformation (1295 cm-1), disaccharides (1462 cm-1) and proteins (amide I, 1672/5 cm-1) were associated with Barrett's oesophagus and OAC tissue differences. These findings show the potential of using Raman microspectroscopy imaging for fast and accurate diagnoses of oesophageal pathologies and establishing subtle molecular changes predisposing to adenocarcinoma in a clinical setting. Graphical abstract Graphical abstract demonstrating how oesophageal tissue is processed through Raman mapping analysis in order to detect spectral differences between stages of oesophageal transformation to adenocarcinoma.


Asunto(s)
Adenocarcinoma/química , Neoplasias Esofágicas/química , Esófago/química , Espectrometría Raman/métodos , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Anciano , Análisis Discriminante , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patología , Esófago/patología , Femenino , Humanos , Masculino , Análisis de Componente Principal
3.
Anal Bioanal Chem ; 412(5): 1077-1086, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31865413

RESUMEN

Meningiomas are the commonest types of tumours in the central nervous system (CNS). It is a benign type of tumour divided into three WHO grades (I, II and III) associated with tumour growth rate and likelihood of recurrence, where surgical outcomes and patient treatments are dependent on the meningioma grade and histological subtype. The development of alternative approaches based on attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy could aid meningioma grade determination and its biospectrochemical profiling in an automated fashion. Herein, ATR-FTIR in combination with chemometric techniques is employed to distinguish grade I, grade II and grade I meningiomas that re-occurred. Ninety-nine patients were investigated in this study where their formalin-fixed paraffin-embedded (FFPE) brain tissue samples were analysed by ATR-FTIR spectroscopy. Subsequent classification was performed via principal component analysis plus linear discriminant analysis (PCA-LDA) and partial least squares plus discriminant analysis (PLS-DA). PLS-DA gave the best results where grade I and grade II meningiomas were discriminated with 79% accuracy, 80% sensitivity and 73% specificity, while grade I versus grade I recurrence and grade II versus grade I recurrence were discriminated with 94% accuracy (94% sensitivity and specificity) and 97% accuracy (97% sensitivity and 100% specificity), respectively. Several wavenumbers were identified as possible biomarkers towards tumour differentiation. The majority of these were associated with lipids, protein, DNA/RNA and carbohydrate alterations. These findings demonstrate the potential of ATR-FTIR spectroscopy towards meningioma grade discrimination as a fast, low-cost, non-destructive and sensitive tool for clinical settings. Graphical abstract Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was used to discriminate meningioma WHO grade I, grade II and grade I recurrence tumours.


Asunto(s)
Neoplasias Meníngeas/química , Meningioma/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Análisis Discriminante , Humanos , Análisis de Componente Principal , Sensibilidad y Especificidad
4.
Br J Neurosurg ; 34(1): 40-45, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31642351

RESUMEN

Introduction: In order for brain tumours to be successfully treated, maximal resection is beneficial. A method to detect infiltrative tumour edges intraoperatively, improving on current methods would be clinically useful. Vibrational spectroscopy offers the potential to provide a handheld, reagent-free method for tumour detection.Purpose: This study was designed to determine the ability of both Raman and Fourier-transform infrared (FTIR) spectroscopy towards differentiating between normal brain tissue, glioma or meningioma.Method: Unfixed brain tissue, which had previously only been frozen, comprising normal, glioma or meningioma tissue was placed onto calcium fluoride slides for analysis using Raman and attenuated total reflection (ATR)-FTIR spectroscopy. Matched haematoxylin and eosin slides were used to confirm tumour areas. Analyses were then conducted to generate a classification model.Results: This study demonstrates the ability of both Raman and ATR-FTIR spectroscopy to discriminate tumour from non-tumour fresh frozen brain tissue with 94% and 97.2% of cases correctly classified, with sensitivities of 98.8% and 100%, respectively. This decreases when spectroscopy is used to determine tumour type.Conclusion: The study demonstrates the ability of both Raman and ATR-FTIR spectroscopy to detect tumour tissue from non-tumour brain tissue with a high degree of accuracy. This demonstrates the ability of spectroscopy when targeted for a cancer diagnosis. However, further improvement would be required for a classification model to determine tumour type using this technology, in order to make this tool clinically viable.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirugía , Procedimientos Neuroquirúrgicos/métodos , Neoplasias Encefálicas/clasificación , Diagnóstico Diferencial , Glioma/clasificación , Glioma/diagnóstico , Humanos , Meningioma/clasificación , Meningioma/diagnóstico , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Conservación de Tejido
5.
Analyst ; 144(23): 7024-7031, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-31650137

RESUMEN

Raman spectroscopy is a powerful technique used to analyse biological materials, where spectral markers such as proteins (1500-1700 cm-1), carbohydrates (470-1200 cm-1) and phosphate groups of DNA (980, 1080-1240 cm-1) can be detected in a complex biological medium. Herein, Raman microspectroscopy imaging was used to investigate 90 brain tissue samples in order to differentiate meningioma Grade I and Grade II samples, which are the commonest types of brain tumour. Several classification algorithms using feature extraction and selection methods were tested, in which the best classification performances were achieved by principal component analysis-quadratic discriminant analysis (PCA-QDA) and successive projections algorithm-quadratic discriminant analysis (SPA-QDA), resulting in accuracies of 96.2%, sensitivities of 85.7% and specificities of 100% using both methods. A biochemical profiling in terms of spectral markers was investigated using the difference-between-mean (DBM) spectrum, PCA loadings, SPA-QDA selected wavenumbers, and the recovered imaging profiles after multivariate curve resolution alternating least squares (MCR-ALS), where the following wavenumbers were found to be associated with class differentiation: 850 cm-1 (amino acids or polysaccharides), 1130 cm-1 (phospholipid structural changes), the region between 1230-1360 cm-1 (Amide III and CH2 deformation), 1450 cm-1 (CH2 bending), and 1858 cm-1 (C[double bond, length as m-dash]O stretching). These findings highlight the potential of Raman microspectroscopy imaging for determination of meningioma tumour grades.


Asunto(s)
Neoplasias Encefálicas/clasificación , Neoplasias Meníngeas/clasificación , Meningioma/clasificación , Algoritmos , Análisis Discriminante , Humanos , Análisis de los Mínimos Cuadrados , Análisis de Componente Principal , Curva ROC , Espectrometría Raman/métodos
6.
Analyst ; 144(24): 7447-7456, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31696873

RESUMEN

Diagnostic tools for the detection of early-stage oesophageal adenocarcinoma (OAC) are urgently needed. Our aim was to develop an accurate and inexpensive method using biofluids (plasma, serum, saliva or urine) for detecting oesophageal stages through to OAC (squamous; inflammatory; Barrett's; low-grade dysplasia; high-grade dysplasia; OAC) using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy. ATR-FTIR spectroscopy coupled with variable selection methods, with successive projections or genetic algorithms (GA) combined with quadratic discriminant analysis (QDA) were employed to identify spectral biomarkers in biofluids for accurate diagnosis in a hospital setting of different stages through to OAC. Quality metrics (Accuracy, Sensitivity, Specificity and F-score) and biomarkers of disease were computed for each model. For plasma, GA-QDA models using 15 wavenumbers achieved 100% classification for four classes. For saliva, PCA-QDA models achieved 100% for the inflammatory stage and high-quality metrics for other classes. For serum, GA-QDA models achieved 100% performance for the OAC stage using 13 wavenumbers. For urine, PCA-QDA models achieved 100% performance for all classes. Selected wavenumbers using a Student's t-test (95% confidence interval) identified a differentiation of the stages on each biofluid: plasma (929 cm-1 to 1431 cm-1, associated with DNA/RNA and proteins); saliva (1000 cm-1 to 1150 cm-1, associated with DNA/RNA region); serum (1435 cm-1 to 1573 cm-1, associated with methyl groups of proteins and Amide II absorption); and, urine (1681 cm-1 to 1777 cm-1, associated with a high frequency vibration of an antiparallel ß-sheet of Amide I and stretching vibration of lipids). Our methods have demonstrated excellent efficacy for a rapid, cost-effective method of diagnosis for specific stages to OAC. These findings suggest a potential diagnostic tool for oesophageal cancer and could be translated into clinical practice.


Asunto(s)
Adenocarcinoma/diagnóstico , Análisis Químico de la Sangre/métodos , Neoplasias Esofágicas/diagnóstico , Saliva/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Orina/química , Adenocarcinoma/sangre , Adenocarcinoma/orina , Algoritmos , Análisis Discriminante , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/orina , Humanos , Estadificación de Neoplasias , Análisis de Componente Principal
7.
Analyst ; 144(22): 6736-6750, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31612875

RESUMEN

Over a third of brain tumour patients visit their general practitioner more than five times prior to diagnosis in the UK, leading to 62% of patients being diagnosed as emergency presentations. Unfortunately, symptoms are non-specific to brain tumours, and the majority of these patients complain of headaches on multiple occasions before being referred to a neurologist. As there are currently no methods in place for the early detection of brain cancer, the affected patients' average life expectancy is reduced by 20 years. These statistics indicate that the current pathway is ineffective, and there is a vast need for a rapid diagnostic test. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy is sensitive to the hallmarks of cancer, as it analyses the full range of macromolecular classes. The combination of serum spectroscopy and advanced data analysis has previously been shown to rapidly and objectively distinguish brain tumour severity. Recently, a novel high-throughput ATR accessory has been developed, which could be cost-effective to the National Health Service in the UK, and valuable for clinical translation. In this study, 765 blood serum samples have been collected from healthy controls and patients diagnosed with various types of brain cancer, contributing to one of the largest spectroscopic studies to date. Three robust machine learning techniques - random forest, partial least squares-discriminant analysis and support vector machine - have all provided promising results. The novel high-throughput technology has been validated by separating brain cancer and non-cancer with balanced accuracies of 90% which is comparable to the traditional fixed diamond crystal methodology. Furthermore, the differentiation of brain tumour type could be useful for neurologists, as some are difficult to distinguish through medical imaging alone. For example, the highly aggressive glioblastoma multiforme and primary cerebral lymphoma can appear similar on magnetic resonance imaging (MRI) scans, thus are often misdiagnosed. Here, we report the ability of infrared spectroscopy to distinguish between glioblastoma and lymphoma patients, at a sensitivity and specificity of 90.1% and 86.3%, respectively. A reliable serum diagnostic test could avoid the need for surgery and speed up time to definitive chemotherapy and radiotherapy.


Asunto(s)
Análisis Químico de la Sangre/estadística & datos numéricos , Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Linfoma/diagnóstico , Espectroscopía Infrarroja por Transformada de Fourier/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Conjuntos de Datos como Asunto , Diagnóstico Diferencial , Análisis Discriminante , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad , Máquina de Vectores de Soporte , Adulto Joven
8.
Int J Cancer ; 142(8): 1620-1626, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29194603

RESUMEN

Many traits of cancer progression (e.g., development of metastases or resistance to therapy) are facilitated by tumour evolution: Darwinian selection of subclones with distinct genotypes or phenotypes that enable such progression. Characterising these subclones provide an opportunity to develop drugs to better target their specific properties but requires the accurate identification of somatic mutations shared across multiple spatiotemporal tumours from the same patient. Current best practices for calling somatic mutations are optimised for single samples, and risk being too conservative to identify shared mutations with low prevalence in some samples. We reasoned that datasets from multiple matched tumours can be used for mutual validation and thus propose an adapted two-stage approach: (1) low-stringency mutation calling to identify mutations shared across samples irrespective of the weight of evidence in a single sample; (2) high-stringency mutation calling to further characterise mutations present in a single sample. We applied our approach to three-independent cohorts of paired primary and recurrent glioblastoma tumours, two of which have previously been analysed using existing approaches, and found that it significantly increased the amount of biologically relevant shared somatic mutations identified. We also found that duplicate removal was detrimental when identifying shared somatic mutations. Our approach is also applicable when multiple datasets e.g. DNA and RNA are available for the same tumour.


Asunto(s)
Glioblastoma/genética , Genotipo , Humanos , Mutación/genética , Recurrencia Local de Neoplasia/genética , Fenotipo
9.
Analyst ; 143(13): 3156-3163, 2018 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-29878018

RESUMEN

The current lack of an accurate, cost-effective and non-invasive test that would allow for screening and diagnosis of gynaecological carcinomas, such as endometrial and ovarian cancer, signals the necessity for alternative approaches. The potential of spectroscopic techniques in disease investigation and diagnosis has been previously demonstrated. Here, we used attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy to analyse urine samples from women with endometrial (n = 10) and ovarian cancer (n = 10), as well as from healthy individuals (n = 10). After applying multivariate analysis and classification algorithms, biomarkers of disease were pointed out and high levels of accuracy were achieved for both endometrial (95% sensitivity, 100% specificity; accuracy: 95%) and ovarian cancer (100% sensitivity, 96.3% specificity; accuracy 100%). The efficacy of this approach, in combination with the non-invasive method for urine collection, suggest a potential diagnostic tool for endometrial and ovarian cancers.


Asunto(s)
Neoplasias Endometriales/diagnóstico , Neoplasias Ováricas/diagnóstico , Espectroscopía Infrarroja por Transformada de Fourier , Urinálisis/métodos , Pruebas Diagnósticas de Rutina , Neoplasias Endometriales/orina , Femenino , Humanos , Análisis Multivariante , Neoplasias Ováricas/orina , Sensibilidad y Especificidad
10.
Mol Carcinog ; 55(3): 268-79, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25620587

RESUMEN

Cyclic nucleotides (cAMP & cGMP) are critical intracellular second messengers involved in the transduction of a diverse array of stimuli and their catabolism is mediated by phosphodiesterases (PDEs). We previously detected focal genomic amplification of PDE1C in >90 glioblastoma multiforme (GBM) cells suggesting a potential as a novel therapeutic target in these cells. In this report, we show that genomic gain of PDE1C was associated with increased expression in low passage GBM-derived cell cultures. We demonstrate that PDE1C is essential in driving cell proliferation, migration and invasion in GBM cultures since silencing of this gene significantly mitigates these functions. We also define the mechanistic basis of this functional effect through whole genome expression analysis by identifying down-stream gene effectors of PDE1C which are involved in cell cycle and cell adhesion regulation. In addition, we also demonstrate that Vinpocetine, a general PDE1 inhibitor, can also attenuate proliferation with no effect on invasion/migration. Up-regulation of at least one of this gene set (IL8, CXCL2, FOSB, NFE2L3, SUB1, SORBS2, WNT5A, and MMP1) in TCGA GBM cohorts is associated with worse outcome and PDE1C silencing down-regulated their expression, thus also indicating potential to influence patient survival. Therefore we conclude that proliferation, migration, and invasion of GBM cells could also be regulated downstream of PDE1C.


Asunto(s)
Neoplasias Encefálicas/patología , Movimiento Celular , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 1/genética , Regulación Neoplásica de la Expresión Génica , Glioblastoma/patología , Invasividad Neoplásica/patología , Encéfalo/metabolismo , Encéfalo/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Proliferación Celular , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 1/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Invasividad Neoplásica/genética , Regulación hacia Arriba
11.
J Neurooncol ; 127(3): 463-72, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26874961

RESUMEN

The ability to diagnose cancer rapidly with high sensitivity and specificity is essential to exploit advances in new treatments to lead significant reductions in mortality and morbidity. Current cancer diagnostic tests observing tissue architecture and specific protein expression for specific cancers suffer from inter-observer variability, poor detection rates and occur when the patient is symptomatic. A new method for the detection of cancer using 1 µl of human serum, attenuated total reflection-Fourier transform infrared spectroscopy and pattern recognition algorithms is reported using a 433 patient dataset (3897 spectra). To the best of our knowledge, we present the largest study on serum mid-infrared spectroscopy for cancer research. We achieve optimum sensitivities and specificities using a Radial Basis Function Support Vector Machine of between 80.0 and 100 % for all strata and identify the major spectral features, hence biochemical components, responsible for the discrimination within each stratum. We assess feature fed-SVM analysis for our cancer versus non-cancer model and achieve 91.5 and 83.0 % sensitivity and specificity respectively. We demonstrate the use of infrared light to provide a spectral signature from human serum to detect, for the first time, cancer versus non-cancer, metastatic cancer versus organ confined, brain cancer severity and the organ of origin of metastatic disease from the same sample enabling stratified diagnostics depending upon the clinical question asked.


Asunto(s)
Algoritmos , Biomarcadores de Tumor/sangre , Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/diagnóstico , Diferenciación Celular , Detección Precoz del Cáncer , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Pronóstico , Máquina de Vectores de Soporte , Adulto Joven
12.
Analyst ; 141(12): 3668-78, 2016 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-26818218

RESUMEN

Fourier transform infrared (FTIR) spectroscopy has long been established as an analytical technique for the measurement of vibrational modes of molecular systems. More recently, FTIR has been used for the analysis of biofluids with the aim of becoming a tool to aid diagnosis. For the clinician, this represents a convenient, fast, non-subjective option for the study of biofluids and the diagnosis of disease states. The patient also benefits from this method, as the procedure for the collection of serum is much less invasive and stressful than traditional biopsy. This is especially true of patients in whom brain cancer is suspected. A brain biopsy is very unpleasant for the patient, potentially dangerous and can occasionally be inconclusive. We therefore present a method for the diagnosis of brain cancer from serum samples using FTIR and machine learning techniques. The scope of the study involved 433 patients from whom were collected 9 spectra each in the range 600-4000 cm(-1). To begin the development of the novel method, various pre-processing steps were investigated and ranked in terms of final accuracy of the diagnosis. Random forest machine learning was utilised as a classifier to separate patients into cancer or non-cancer categories based upon the intensities of wavenumbers present in their spectra. Generalised 2D correlational analysis was then employed to further augment the machine learning, and also to establish spectral features important for the distinction between cancer and non-cancer serum samples. Using these methods, sensitivities of up to 92.8% and specificities of up to 91.5% were possible. Furthermore, ratiometrics were also investigated in order to establish any correlations present in the dataset. We show a rapid, computationally light, accurate, statistically robust methodology for the identification of spectral features present in differing disease states. With current advances in IR technology, such as the development of rapid discrete frequency collection, this approach is of importance to enable future clinical translation and enables IR to achieve its potential.


Asunto(s)
Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/diagnóstico , Suero/química , Espectroscopía Infrarroja por Transformada de Fourier , Biopsia , Humanos , Sensibilidad y Especificidad
13.
Analyst ; 142(1): 98-109, 2016 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-27757448

RESUMEN

Spectroscopic diagnostics have been shown to be an effective tool for the analysis and discrimination of disease states from human tissue. Furthermore, Raman spectroscopic probes are of particular interest as they allow for in vivo spectroscopic diagnostics, for tasks such as the identification of tumour margins during surgery. In this study, we investigate a feature-driven approach to the classification of metastatic brain cancer, glioblastoma (GB) and non-cancer from tissue samples, and we provide a real-time feedback method for endoscopic diagnostics using sound. To do this, we first evaluate the sensitivity and specificity of three classifiers (SVM, KNN and LDA), when trained with both sub-band spectral features and principal components taken directly from Raman spectra. We demonstrate that the feature extraction approach provides an increase in classification accuracy of 26.25% for SVM and 25% for KNN. We then discuss the molecular assignment of the most salient sub-bands in the dataset. The most salient sub-band features are mapped to parameters of a frequency modulation (FM) synthesizer in order to generate audio clips from each tissue sample. Based on the properties of the sub-band features, the synthesizer was able to maintain similar sound timbres within the disease classes and provide different timbres between disease classes. This was reinforced via listening tests, in which participants were able to discriminate between classes with mean classification accuracy of 71.1%. Providing intuitive feedback via sound frees the surgeons' visual attention to remain on the patient, allowing for greater control over diagnostic and surgical tools during surgery, and thus promoting clinical translation of spectroscopic diagnostics.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Sonido , Espectrometría Raman , Neoplasias Encefálicas/patología , Glioblastoma/patología , Humanos , Metástasis de la Neoplasia , Sensibilidad y Especificidad , Estadística como Asunto , Factores de Tiempo
14.
Analyst ; 139(2): 446-54, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24308030

RESUMEN

Raman spectroscopy is a non-destructive, non-invasive, rapid and economical technique which has the potential to be an excellent method for the diagnosis of cancer and understanding disease progression through retrospective studies of archived tissue samples. Historically, biobanks are generally comprised of formalin fixed paraffin preserved tissue and as a result these specimens are often used in spectroscopic research. Tissue in this state has to be dewaxed prior to Raman analysis to reduce paraffin contributions in the spectra. However, although the procedures are derived from histopathological clinical practice, the efficacy of the dewaxing procedures that are currently employed is questionable. Ineffective removal of paraffin results in corruption of the spectra and previous experiments have shown that the efficacy can depend on the dewaxing medium and processing time. The aim of this study was to investigate the influence of commonly used spectroscopic substrates (CaF2, Spectrosil quartz and low-E slides) and the influence of different histological tissue types (normal, cancerous and metastatic) on tissue preparation and to assess their use for spectral histopathology. Results show that CaF2 followed by Spectrosil contribute the least to the spectral background. However, both substrates retain paraffin after dewaxing. Low-E substrates, which exhibit the most intense spectral background, do not retain wax and resulting spectra are not affected by paraffin peaks. We also show a disparity in paraffin retention depending upon the histological identity of the tissue with abnormal tissue retaining more paraffin than normal.


Asunto(s)
Técnicas de Preparación Histocitológica/métodos , Neoplasias/patología , Espectrometría Raman , Adulto , Anciano , Anciano de 80 o más Años , Eosina Amarillenta-(YS)/metabolismo , Femenino , Hematoxilina/metabolismo , Técnicas de Preparación Histocitológica/normas , Humanos , Masculino , Persona de Mediana Edad , Estándares de Referencia , Coloración y Etiquetado , Ceras/aislamiento & purificación
15.
Anal Bioanal Chem ; 405(23): 7347-55, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23831829

RESUMEN

The ability to diagnose brain cancer rapidly from serum samples is of great interest; such a diagnosis would allow for rapid testing and time to results providing a responsive diagnostic environment, ability to monitor treatment efficacy, early detection of recurrent tumours and screening techniques. Current methods rely upon subjective, time-consuming tests such as histological grading and are particularly invasive with the diagnostic test requiring hospitalisation of 2-3 days. A rapid diagnostic method based upon serum samples would allow for a relatively non-invasive test and open up the possibility of screening for brain cancer. We report for the first time the use of a Bioplex immunoassay to provide cytokine and angiogenesis factor levels that differ between serum from glioma and non-cancer patients specifically angiopoietin, follistatin, HGF, IL-8, leptin, PDGF-BB and PECAM-1 providing sensitivities and specificities as high as 88 % and 81 %, respectively. We also report, for the first time, the use of serum ATR-FTIR combined with a RBF SVM for the diagnosis of gliomas from non-cancer patients with sensitivities and specificities as high as 87.5 % and 100 %, respectively. We describe the combination of these techniques in an orthogonal diagnostic regime, providing strength to the diagnosis through data combinations, in a rapid diagnostic test within 5 h from serum collection (10 min for ATR-FTIR and 4 h for the Bioplex Immunoassay). This regime has the ability to revolutionise the clinical environment by providing objective measures for diagnosis allowing for increased efficiency with corresponding decreases in mortality, morbidity and economic impact upon the health services.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Angiopoyetinas/sangre , Becaplermina , Neoplasias Encefálicas/sangre , Estudios de Casos y Controles , Análisis Factorial , Femenino , Folistatina/sangre , Glioma/sangre , Factor de Crecimiento de Hepatocito/sangre , Humanos , Inmunoensayo , Interleucina-8/sangre , Leptina/sangre , Masculino , Persona de Mediana Edad , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/sangre , Proteínas Proto-Oncogénicas c-sis/sangre , Sensibilidad y Especificidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Factores de Tiempo
16.
J Pers Med ; 13(8)2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37623527

RESUMEN

This study presents ATR-FTIR (attenuated total reflectance Fourier-transform infrared) spectral analysis of ex vivo oesophageal tissue including all classifications to oesophageal adenocarcinoma (OAC). The article adds further validation to previous human tissue studies identifying the potential for ATR-FTIR spectroscopy in differentiating among all classes of oesophageal transformation to OAC. Tissue spectral analysis used principal component analysis quadratic discriminant analysis (PCA-QDA), successive projection algorithm quadratic discriminant analysis (SPA-QDA), and genetic algorithm quadratic discriminant analysis (GA-QDA) algorithms for variable selection and classification. The variables selected by SPA-QDA and GA-QDA discriminated tissue samples from Barrett's oesophagus (BO) to OAC with 100% accuracy on the basis of unique spectral "fingerprints" of their biochemical composition. Accuracy test results including sensitivity and specificity were determined. The best results were obtained with PCA-QDA, where tissues ranging from normal to OAC were correctly classified with 90.9% overall accuracy (71.4-100% sensitivity and 89.5-100% specificity), including the discrimination between normal and inflammatory tissue, which failed in SPA-QDA and GA-QDA. All the models revealed excellent results for distinguishing among BO, low-grade dysplasia (LGD), high-grade dysplasia (HGD), and OAC tissues (100% sensitivities and specificities). This study highlights the need for further work identifying potential biochemical markers using ATR-FTIR in tissue that could be utilised as an adjunct to histopathological diagnosis for early detection of neoplastic changes in susceptible epithelium.

17.
Br J Neurosurg ; 26(3): 336-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22103566

RESUMEN

OBJECTIVE: Glioblastoma multiforme is a malignant primary brain tumour with very limited treatment options. Any addition to existing treatment options which can improve prognosis and life expectancy is useful. In our study, we look at the usefulness of anti-progestogen mifepristone in causing growth suppression of glioma cell lines in the laboratory. METHODS: We cultured five cell lines in the lab and exposed them to mifepristone in different doses for a total of 96 h. Five different doses of mifepristone were used. Progesterone and dexamethasone were also used as growth stimulants. Immunostaining was used to identify progesterone receptors (PRs) in the cell lines. RESULTS: U257/7 and IN1265 showed statistically significant growth suppression (36% and 11%, P = 0.001 and 0.03 respectively), maximal at 96 h. Growth suppression in U257/7 showed a dose response progression except with the lowest dose which was not explicable. The response of IN1265 was seen only with the highest dose of mifepristone. There was no significant growth stimulation with either dexamethasone or progesterone. None of the cell lines showed any significant positivity for PRs. CONCLUSION: We were able to produce enough growth suppression of glioma cell lines using mifepristone. This is in keeping with some of the published results in literature. This raises the possibility of using mifepristone in treating GBMs which have very limited treatment options. This, however, needs further work probably on primary glioma cultures first followed by in vivo studies before it can be used in patients.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Mifepristona/farmacología , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Glioblastoma/patología , Humanos
18.
J Neurotrauma ; 39(11-12): 773-783, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35236121

RESUMEN

Computed tomography (CT) brain imaging is routinely used to support clinical decision-making in patients with traumatic brain injury (TBI). Only 7% of scans, however, demonstrate evidence of TBI. The other 93% of scans contribute a significant cost to the healthcare system and a radiation risk to patients. There may be better strategies to identify which patients, particularly those with mild TBI, are at risk of deterioration and require hospital admission. We introduce a blood serum liquid biopsy that utilizes attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy with machine learning algorithms as a decision-making tool to identify which patients with mild TBI will most likely present with a positive CT scan. Serum samples were obtained from patients (n = 298) patients who had acquired a TBI and were enrolled in CENTER-TBI and from asymptomatic control patients (n = 87). Injury patients (all severities) were stratified against non-injury controls. The cohort with mild TBI was further examined by stratifying those who had at least one CT abnormality against those who had no CT abnormalities. The test performed exceptionally well in classifications of patients with mild injury versus non-injury controls (sensitivity = 96.4% and specificity = 98.0%) and also provided a sensitivity of 80.2% when stratifying mild patients with at least one CT abnormality against those without. The results provided illustrate the test ability to identify four of every five CT abnormalities and show great promise to be introduced as a triage tool for CT priority in patients with mild TBI.


Asunto(s)
Conmoción Encefálica , Lesiones Traumáticas del Encéfalo , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Hospitales , Humanos , Análisis Espectral , Tomografía Computarizada por Rayos X , Triaje
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 273: 121018, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35189493

RESUMEN

Meningiomas remains a clinical dilemma. They are the commonest "benign" types of brain tumours and, although being typically benign, they are divided into three WHO grades categories (I, II and III) which are associated with the tumour growth rate and likelihood of recurrence. Recurrence depends on extend of surgery as well as histopathological diagnosis. There is a marked variation amongst surgeons in the follow-up arrangements for their patients even within the same unit which has a significant clinical, and financial implication. Knowing the tumour grade rapidly is an important factor to predict surgical outcomes and adequate patient treatment. Clinical follow up sometimes is haphazard and not based on clear evidence. Spectrochemical techniques are a powerful tool for cancer diagnostics. Raman hyperspectral imaging is able to generate spatially-distributed spectrochemical signatures with great sensitivity. Using this technique, 95 brain tissue samples (66 meningiomas WHO grade I, 24 meningiomas WHO grade II and 5 meningiomas that reoccurred) were analysed in order to discriminate grade I and grade II samples. Newly-developed three-dimensional discriminant analysis algorithms were used to process the hyperspectral imaging data in a 3D fashion. Three-dimensional principal component analysis quadratic discriminant analysis (3D-PCA-QDA) was able to distinguish grade I and grade II meningioma samples with 96% test accuracy (100% sensitivity and 95% specificity). This technique is here shown to be a high-throughput, reagent-free, non-destructive, and can give accurate predictive information regarding the meningioma tumour grade, hence, having enormous clinical potential with regards to being developed for intra-operative real-time assessment of disease.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Meníngeas , Meningioma , Neoplasias Encefálicas/diagnóstico por imagen , Niño , Análisis Discriminante , Humanos , Imágenes Hiperespectrales , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/patología , Meningioma/diagnóstico por imagen , Meningioma/patología
20.
Sci Rep ; 12(1): 1102, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-35058523

RESUMEN

Brain metastases comprise 40% of all metastatic tumours and breast tumours are among the tumours that most commonly metastasise to the brain, the role that epigenetic gene dysregulation plays in this process is not well understood. We carried out 450 K methylation array analysis to investigate epigenetically dysregulated genes in breast to brain metastases (BBM) compared to normal breast tissues (BN) and primary breast tumours (BP). For this, we referenced 450 K methylation data for BBM tumours prepared in our laboratory with BN and BP from The Cancer Genome Atlas. Experimental validation on our initially identified genes, in an independent cohort of BP and in BBM and their originating primary breast tumours using Combined Bisulphite and Restriction Analysis (CoBRA) and Methylation Specific PCR identified three genes (RP11-713P17.4, MIR124-2, NUS1P3) that are hypermethylated and three genes (MIR3193, CTD-2023M8.1 and MTND6P4) that are hypomethylated in breast to brain metastases. In addition, methylation differences in candidate genes between BBM tumours and originating primary tumours shows dysregulation of DNA methylation occurs either at an early stage of tumour evolution (in the primary tumour) or at a later evolutionary stage (where the epigenetic change is only observed in the brain metastasis). Epigentic changes identified could also be found when analysing tumour free circulating DNA (tfcDNA) in patient's serum taken during BBM biopsies. Epigenetic dysregulation of RP11-713P17.4, MIR3193, MTND6P4 are early events suggesting a potential use for these genes as prognostic markers.


Asunto(s)
Neoplasias Encefálicas/genética , Epigénesis Genética/genética , ARN no Traducido/genética , Biomarcadores de Tumor/genética , Encéfalo/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , ADN/genética , Metilación de ADN/genética , Bases de Datos Genéticas , Epigenómica , Femenino , Expresión Génica/genética , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , MicroARNs , Metástasis de la Neoplasia/genética , Pronóstico , Regiones Promotoras Genéticas/genética , Receptores de Superficie Celular , Transcriptoma/genética
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