Detection of urinary bladder cancer cells using redox ratio and double excitation wavelengths autofluorescence

Dual-mode OCT/fluorescence system for monitoring the morphology and metabolism of laser-printed 3D full-thickness skin equivalents

The 3D structure of native human skin is fundamental for studying skin health, diseases, wound healing, and for testing the safety of skin care products, as well as personalized treatments for skin conditions. Tissue regeneration, driven by tissue engineering, often involves creating full-thickness skin equivalents (FSE), which are widely used for developing both healthy and diseased skin models. In this study, we utilized human skin cell lines to create FSE. We designed high-resolution 3D scaffolds to support the growth and maturation of these skin models. Additionally, we developed and validated a cost-effective, custom-built system combining fluorescence spectroscopy (FS) and optical coherence tomography (OCT) for non-destructive analysis of the metabolism and morphology of 3D FSEs. This system proved highly sensitive in detecting fluorescence from key metabolic co-enzymes (NADH and FAD) in solutions and cell suspensions, while OCT provided adequate resolution to observe the morphology of FSEs. As a result, both the 3D FSE model and the dual-mode optical system hold significant potential for use in 3D bioprinting of biological tissues, as well as in the development of cosmetics, drugs, and in monitoring their maturation over time.

Metabolic light absorption, scattering, and emission (MetaLASE) microscopy

Optical imaging of metabolism can provide key information about health and disease progression in cells and tissues; however, current methods have lacked gold-standard information about histological structure. Conversely, histology and virtual histology methods have lacked metabolic contrast. Here, we present metabolic light absorption, scattering, and emission (MetaLASE) microscopy, which rapidly provides a virtual histology and optical metabolic readout simultaneously. Hematoxylin-like nucleic contrast and eosin-like cytoplasmic contrast are obtained using photoacoustic remote sensing and ultraviolet reflectance microscopy, respectively. The same ultraviolet source excites endogenous Nicotinamide adenine dinucleotide (phosphate), flavin adenine dinucleotide, and collagen autofluorescence, providing a map of optical redox ratios to visualize metabolic variations including in areas of invasive carcinoma. Benign chronic inflammation and glands also are seen to exhibit hypermetabolism. MetaLASE microscopy offers promise for future applications in intraoperative margin analysis and in research applications where greater insights into metabolic activity could be correlated with cell and tissue types.

Label-free spatially maintained measurements of metabolic phenotypes in cells

Metabolic reprogramming at a cellular level contributes to many diseases including cancer, yet few assays are capable of measuring metabolic pathway usage by individual cells within living samples. Here, autofluorescence lifetime imaging is combined with single-cell segmentation and machine-learning models to predict the metabolic pathway usage of cancer cells. The metabolic activities of MCF7 breast cancer cells and HepG2 liver cancer cells were controlled by growing the cells in culture media with specific substrates and metabolic inhibitors. Fluorescence lifetime images of two endogenous metabolic coenzymes, reduced nicotinamide adenine dinucleotide (NADH) and oxidized flavin adenine dinucleotide (FAD), were acquired by a multi-photon fluorescence lifetime microscope and analyzed at the cellular level. Quantitative changes of NADH and FAD lifetime components were observed for cells using glycolysis, oxidative phosphorylation, and glutaminolysis. Conventional machine learning models trained with the autofluorescence features classified cells as dependent on glycolytic or oxidative metabolism with 90%-92% accuracy. Furthermore, adapting convolutional neural networks to predict cancer cell metabolic perturbations from the autofluorescence lifetime images provided improved performance, 95% accuracy, over traditional models trained via extracted features. Additionally, the model trained with the lifetime features of cancer cells could be transferred to autofluorescence lifetime images of T cells, with a prediction that 80% of activated T cells were glycolytic, and 97% of quiescent T cells were oxidative. In summary, autofluorescence lifetime imaging combined with machine learning models can detect metabolic perturbations between glycolysis and oxidative metabolism of living samples at a cellular level, providing a label-free technology to study cellular metabolism and metabolic heterogeneity.

CyTOF analysis identifies unusual immune cells in urine of BCG-treated bladder cancer patients

High grade non-muscle-invasive bladder tumours are treated with transurethral resection followed by recurrent intravesical instillations of Bacillus Calmette Guérin (BCG). Although most bladder cancer patients respond well to BCG, there is no clinical parameter predictive of treatment response, and when treatment fails, the prognosis is very poor. Further, a high percentage of NMIBC patients treated with BCG suffer unwanted effects that force them to stop treatment. Thus, early identification of patients in which BCG treatment will fail is really important. Here, to identify early stage non-invasive biomarkers of non-responder patients and patients at risk of abandoning the treatment, we longitudinally analysed the phenotype of cells released into the urine of bladder cancer patients 3-7 days after BCG instillations. Mass cytometry (CyTOF) analyses revealed a large proportion of granulocytes and monocytes, mostly expressing activation markers. A novel population of CD15⁺CD66b⁺CD14⁺CD16⁺ cells was highly abundant in several samples; expression of these markers was confirmed using flow cytometry and qPCR. A stronger inflammatory response was associated with increased cell numbers in the urine; this was not due to hematuria because the cell proportions were distinct from those in the blood. This pilot study represents the first CyTOF analysis of cells recruited to urine during BCG treatment, allowing identification of informative markers associated with treatment response for sub-selection of markers to confirm using conventional techniques. Further studies should jointly evaluate cells and soluble factors in urine in larger cohorts of patients to characterise the arms of the immune response activated in responders and to identify patients at risk of complications from BCG treatment.

Development of an optical fiber-based redox monitoring system for tissue metabolism

An optical redox ratio can potentially be used to report on the dynamics of cell and tissue metabolism and define altered metabolic conditions for different pathologies. While there are methods to measure the optical redox ratio, they are not particularly suited to real-time in situ or in vivo analysis. Here, we have developed a fiber-optic system to measure redox ratios in cells and tissues and two mathematical models to enable real-time, in vivo redox measurements. The optical redox ratios in tissue explants are correlated directly with endogenous NADH/FAD fluorescence emissions. We apply the mathematical models to the two-photon microscopy data and show consistent results. We also used our fiber-optic system to measure redox in different tissues and show consistent results between the two models, hence demonstrating proof-of-principle. This innovative redox monitoring system will have practical applications for defining different metabolic disease states.

The feasibility of multimodal fiber optic spectroscopy analysis in bladder cancer detection, grading, and staging

OBJECTIVE

To prove the feasibility of Multimodal Fiber Optic Spectroscopy (MFOS) analysis in bladder cancer (BCa) detection, grading, and staging.

MATERIALS AND METHODS

Bladder specimens from patients underwent TURBT or TURP were recorded and analyzed with MFOS within 30 min from excision. In detail, our MFOS combined fluorescence, Raman spectroscopy, and diffuse reflectance. We used these optical techniques to collect spectra from bladder biopsies, then we compared the obtained results to gold standard pathological analysis. Finally, we developed a classification algorithm based on principal component analysis-linear discriminant analysis.

RESULTS

A total of 169 specimens were collected and analyzed from 114 patients, 40 (23.7%) healthy (from TURP), and 129 (76.3%) with BCa. BCa specimens were divided according to their grade-34 (26.4%) low grade (LG) and 95 (73.6%) high grade (HG) BCa-and stage-64 (49.6%) Ta, 45 (34.9%) T1, and 20 (15.5%) T2. MFOS-based classification algorithm correctly discriminated healthy versus BCa with 90% accuracy, HG versus LG with 83% accuracy. Furthermore, it assessed tumor stage with 75% accuracy for Ta versus T1, 85% for T1 versus T2, and 86% for Ta versus T2.

CONCLUSIONS

Our preliminary results suggest that MFOS could be a reliable, fast, and label-free tool for BCa assessment, providing also grading and staging information. This technique could be applied in future for in vivo inspection as well as of ex vivo tissue biopsies. Thus, MFOS might improve urothelial cancer management. Further studies are required.

Machine Learning Aided Photonic Diagnostic System for Minimally Invasive Optically Guided Surgery in the Hepatoduodenal Area

Abdominal cancer is a widely prevalent group of tumours with a high level of mortality if diagnosed at a late stage. Although the cancer death rates have in general declined over the past few decades, the mortality from tumours in the hepatoduodenal area has significantly increased in recent years. The broader use of minimal access surgery (MAS) for diagnostics and treatment can significantly improve the survival rate and quality of life of patients after surgery. This work aims to develop and characterise an appropriate technical implementation for tissue endogenous fluorescence (TEF) and assess the efficiency of machine learning methods for the real-time diagnosis of tumours in the hepatoduodenal area. In this paper, we present the results of the machine learning approach applied to the optically guided MAS. We have elaborated tissue fluorescence approach with a fibre-optic probe to record the TEF and blood perfusion parameters during MAS in patients with cancers in the hepatoduodenal area. The measurements from the laser Doppler flowmetry (LDF) channel were used as a sensor of the tissue vitality to reduce variability in TEF data. Also, we evaluated how the blood perfusion oscillations are changed in the tumour tissue. The evaluated amplitudes of the cardiac (0.6-1.6 Hz) and respiratory (0.2-0.6 Hz) oscillations was significantly higher in intact tissues (p < 0.001) compared to the cancerous ones, while the myogenic (0.2-0.06 Hz) oscillation did not demonstrate any statistically significant difference. Our results demonstrate that a fibre-optic TEF probe accompanied with ML algorithms such as k-Nearest Neighbours or AdaBoost is highly promising for the real-time in situ differentiation between cancerous and healthy tissues by detecting the information about the tissue type that is encoded in the fluorescence spectrum. Also, we show that the detection can be supplemented and enhanced by parallel collection and classification of blood perfusion oscillations.

Fluorescence intensity and lifetime redox ratios detect metabolic perturbations in T cells

The auto-fluorescent coenzymes reduced nicotinamide dinucleotide (NADH) and oxidized flavin adenine dinucleotide (FAD) allow label-free detection of cellular metabolism. The optical redox ratio, which is traditionally computed as the ratio of NADH and FAD intensities, allows quantification of cell redox state. In addition to multiple formulations of the optical redox ratio from NADH and FAD intensity measurements, a fluorescence lifetime redox ratio (FLIRR) based on the fractions of protein-bound NADH and FAD was developed to overcome the limitations of experimental factors that influence fluorescence intensity measurements. In this paper, we compare fluorescence-intensity computations of the optical redox ratio with the fluorescence lifetime redox ratio for quiescent and activated T cells. Fluorescence lifetime images of NAD(P)H and FAD of T cells were acquired with a two-photon fluorescence lifetime microscope. Metabolic perturbation experiments, including inhibition of glycolysis, oxidative phosphorylation, glutaminolysis, and fatty acid synthesis revealed differences between the intensity and lifetime redox ratios. Statistical analysis reveals that the FLIRR has a lower standard deviation and skewness (two-tail T-test, P value = 0.05) than the intensity redox ratio. Correlation analysis revealed a weak relationship between FLIRR and intensity redox ratio for individual cells, with a stronger correlation identified for activated T cells (Linear regression, R-value = 0.450) than quiescent T cells (R-value = 0.172). Altogether, the results demonstrate that while both the fluorescence lifetime and intensity redox ratios resolve metabolic perturbations in T cells, the endpoints are influenced by different metabolic processes.

Optical percutaneous needle biopsy of the liver: a pilot animal and clinical study

This paper presents the results of the experiments which were performed using the optical biopsy system specially developed for in vivo tissue classification during the percutaneous needle biopsy (PNB) of the liver. The proposed system includes an optical probe of small diameter acceptable for use in the PNB of the liver. The results of the feasibility studies and actual tests on laboratory mice with inoculated hepatocellular carcinoma and in clinical conditions on patients with liver tumors are presented and discussed. Monte Carlo simulations were carried out to assess the diagnostic volume and to trace the sensing depth. Fluorescence and diffuse reflectance spectroscopy measurements were used to monitor metabolic and morphological changes in tissues. The tissue oxygen saturation was evaluated using a recently developed approach to neural network fitting of diffuse reflectance spectra. The Support Vector Machine Classification was applied to identify intact liver and tumor tissues. Analysis of the obtained results shows the high sensitivity and specificity of the proposed multimodal method. This approach allows to obtain information before the tissue sample is taken, which makes it possible to significantly reduce the number of false-negative biopsies.

Fluorescence biomarkers of malignant melanoma detectable in urine

Malignant melanoma (MM) is a cancerous transformation of melanocytes. It is a disease with the worst response to therapy and, compared to other malignancies, presents much earlier with metastases. MM still belongs to relatively late-detected malignant diseases. Even so, the MM mortality rate is up to 96% for a relatively small incidence (5%). The gold standard for MM diagnosis is a histopathological examination that requires invasive surgery. An invasive sampling method of a biological material can be a stressful factor for the patient, which is often the reason why patients do not seek medical assistance as soon as possible. Our goal was to find a link between metabolites in urine and the stage of MM. Two excitation peaks at 360–370 nm and 450 nm were characterised in spectra of urine samples. The emission spectra have shown one significant peak at 410–460 nm. After addition of glutathione reductase to the samples, fluorescence dropped down only in patient samples and hidden fluorophores appeared. Malignant diseases are associated with the presence of specific metabolites that can be detected fluorescently in biological material such as urine, which can be a suitable alternative for an early detection of cancer or for tracking changes during and after treatment.

Discriminating different grades of cervical intraepithelial neoplasia based on label-free phasor fluorescence lifetime imaging microscopy

This study proposed label-free fluorescence lifetime imaging and phasor analysis methods to discriminate different grades of cervical intraepithelial neoplasia (CIN). The human cervical tissue lesions associated with cellular metabolic abnormalities were detected by the status changes of important coenzymes in cells and tissues, reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD). Fluorescence lifetime imaging microscopy (FLIM) was used to study human cervical tissues, human cervical epithelial cells, and standard samples. Phasor analysis was applied to reveal the interrelation between the metabolic changes and cancer development, which can distinguish among different stages of cervical lesions from low risk to high risk. This approach also possessed high sensitivity, especially for healthy sites of CIN3 tissues, and indicated the dominance of the glycolytic pathway over oxidative phosphorylation in high-grade cervical lesions. This highly adaptive, sensitive, and rapid diagnostic tool exhibits a great potential for cervical precancer diagnosis.

Label-free grading and staging of urothelial carcinoma through multimodal fibre-probe spectroscopy

Urothelial carcinoma (UC) is the most common bladder tumour. Proper treatment requires tumour resection for diagnosing its grade (aggressiveness) and stage (invasiveness). White-light cystoscopy and histopathological examination are the gold standard procedures for clinical and histopathological diagnostics, respectively. However, cystoscopy is limited in terms of specificity, histology requires long tissue processing, both procedures rely on operator's experience. Multimodal optical spectroscopy can provide a powerful tool for detecting, staging and grading bladder tumours in a fast, reliable and label-free modality. In this study, we collected fluorescence, Raman and reflectance spectra from 50 biopsies obtained from 32 patients undergoing transurethral resection of bladder tumour using a multimodal fibre-probe. Principal component analysis allowed distinguishing normal from pathological tissues, as well as discriminating tumour stages and grades. Each individual spectroscopic technique provided high specificity and sensitivity in classifying all tissues; however, a multimodal approach resulted in a considerable increase in diagnostic accuracy (≥95%), which is of paramount importance for tumour grading and staging. The presented method offers the potential for being applied in cystoscopy and for providing an automated diagnosis of UC at the clinical level, with an improvement with respect to current state-of-the-art procedures.

Optical sensory arrays for the detection of urinary bladder cancer-related volatile organic compounds

Non-invasive detection of urinary bladder cancer remains a significant challenge. Urinary volatile organic compounds (VOCs) are a promising alternative to cell-based biomarkers. Herein, we demonstrate a novel diagnosis system based on an optic fluorescence sensor array for detecting urinary bladder cancer VOCs biomarkers. This study describes a fluorescence-based VOCs sensor array detecting system in detail. The choice of VOCs for the initial part was based on an extensive systematic search of the literature and then followed up using urinary samples from patients with urinary bladder transitional cell carcinoma. Canonical discriminant analysis and partial least squares discriminant analysis (PLS-DA) were employed and correctly detected 31/48 urinary bladder cancer VOC biomarkers and achieved an overall 77.75% sensitivity and 93.25% specificity by PLS-DA modelling. All five urine samples from bladder cancer patients, and five healthy controls were successfully identified with the same sensor arrays. Overall, the experiments in this study describe a real-time platform for non-invasive bladder cancer diagnosis using fluorescence-based gas-sensor arrays. Pure VOCs and urine samples from the patients proved such a system to be promising; however, further research is required using a larger population sample.

Methods for bladder cancer diagnosis - The role of autofluorescence and photodynamic diagnosis

Bladder cancer is one of the most common Genito-urinary malignant tumors in humans. Improved diagnostic and therapeutic methods that aim to reduce rates of recurrence and progression of bladder cancer are needed. In current publications, one can find information on such methods as Raman spectroscopy, ultraviolet autofluorescence microscopy, confocal laser endoscopy, photoacoustic imaging, molecular imaging, multi-photon microscopy and many other new diagnostic techniques. These methods do not show significant adverse effects and are procedures well tolerated by patients as they use mostly physical phenomena that are neutral towards the human body. This review highlights the techniques of autofluorescence (AF) or laser induced fluorescence (LIF) and photodynamic diagnostics (PDD) which have been widely clinically studied for many years as a complement to cystoscopy. These methods can be performed during standard cystoscopy and they can be used in routine practice. This review shows that Autofluorescent and Photodynamic diagnostics are effective and have great potential in enhancing the diagnosis of bladder cancer. However, more research should be performed to help realize their full potential.

Metabolic activation triggered by cAMP in MCF-7 cells generates lethal vulnerability to combined oxamate/etomoxir

BACKGROUND

Altered energy metabolism is a biochemical fingerprint of cancer cells, widely recognized as one of the "hallmarks of cancer". Cancer cells show highly increased rates of glucose uptake and glycolysis, after which the resulting pyruvate is converted to lactate. The maintenance of this metabolic asset is warranted by lactate dehydrogenase A (LDH-A) and for this reason the development of novel LDH-targeted anticancer therapeutics is underway. However, possible interference in cancer cell metabolism could also arise from cAMP signaling pathway, which could be activated by either oncogenic induction or exogenously, as a result of microenvironment-derived stimuli, increasing cellular cAMP levels. This study aimed at evaluating the impact of activated cAMP signaling pathway on the efficacy of an LDH-targeted anticancer approach.

METHODS

We exogenously activated cAMP signaling in MCF-7 human breast cancer cells and explored the metabolic interplay between LDH-A and cAMP pathway.

RESULTS

In cAMP-activated cells, we evidenced changes in energy metabolism which reduced their response to LDH inhibition. Interestingly, these experiments also highlighted a potential vulnerability state of treated cells.

CONCLUSIONS

cAMP-induced metabolic changes made MCF-7 cells a preferential target of a drug combination treatment which should not affect normal cell viability.

GENERAL SIGNIFICANCE

cAMP is a well-recognized second messenger of the pro-inflammatory cascade. The obtained results are relevant in consideration of the crucial role played by inflammation in normal breast cell transformation and in cancer progression. Furthermore, they corroborate the idea of exploiting the metabolic changes observed in cancer cells to obtain a therapeutic advantage.

Two-photon optical imaging, spectral and fluorescence lifetime analysis to discriminate urothelial carcinoma grades

In the framework of urologic oncology, mini-invasive procedures have increased in the last few decades particularly for urothelial carcinoma. One of the essential elements in the management of this disease is still the diagnosis, which strongly influences the choice of treatment. The histopathologic evaluation of the tumor grade is a keystone of diagnosis, and tumor characterization is not possible with just a macroscopic evaluation. Even today intraoperative evaluation remains difficult despite the emergence of new technologies which use exogenous fluorophore. This study assessed an optical multimodal technique based on endogenous fluorescence, combining qualitative and quantitative analysis, for the diagnostic of urothelial carcinoma. It was found that the combination of two-photon fluorescence, second harmonic generation microscopy, spectral analysis and fluorescence lifetime imaging were all able to discriminate tumor from healthy tissue, and to determine the grade of tumors. Spectral analysis of fluorescence intensity and the redox ratio used as quantitative evaluations showed statistical differences between low-grade and high-grade tumors. These results showed that multimodal optical analysis is a promising technology for the development of an optical fiber setup designed for an intraoperative diagnosis of urothelial carcinoma in the area of endo-urology.

Label-free imaging and spectroscopy for early detection of cervical cancer

The label-free imaging and spectroscopy method was studied on cervical unstained tissue sections obtained from 36 patients. The native fluorescence spectra of tissues are analyzed by the optical redox ratio (ORR), which is defined as fluorescence intensity ratio between NADH and FAD, and indicates the metabolism change with the cancer development. The ORRs of normal tissues are consistently higher than those of precancer or cancerous tissues. A criterion line of ORR at 5.0 can be used to discriminate cervical precancer/cancer from normal tissues. The sensitivity and specificity of the native fluorescence spectroscopy method for cervical cancer diagnosis are determined as 100% and 91%. Moreover, the native fluorescence spectroscopy study is much more sensitive on the healthy region of cervical precancer/cancer patients compared with the traditional clinical staining method. The results suggest label-free imaging and spectroscopy is a fast, highly sensitive and specific method on the detection of cervical cancer.

Using Fluorescence Spectroscopy To Identify Milk from Grass-Fed Dairy Cows and To Monitor Its Photodegradation

Owing to its high ω-3 fatty acid content, milk from grass-fed dairy cows is becoming increasingly more attractive to consumers. Consequently, it is important to identify the origins of such products and to measure their content, at least relative to some standard. To date, chromatography has been the most extensively used technique. Sample preparation and cost, however, often reduce its widespread applicability. Here, we report the effectiveness of fluorescence spectroscopy for such quantification by measuring the amount of chlorophyll metabolites in the sample. Their content is significantly higher for milk from grass-fed cows compared to milk from grain/silage-fed cows. It is 0.11-0.13 μM in milk samples from grass-fed cows, whereas in milk from cows fed grain/silage rations, the concentration was 0.01-0.04 μM. In various organic milk samples, the chlorophyll metabolite concentration was in the range of 0.07-0.09 μM. In addition, we explored the mechanisms of photodegradation of milk. Riboflavin and chlorophyll metabolites act as photosensitizers in milk for type-I and type-II reactions, respectively. It was also observed that the presence of high levels of chlorophyll metabolites can synergistically degrade riboflavin, contributing to the degradation of milk quality.

Case series about ex vivo identification of squamous cell carcinomas by laser-induced autofluorescence and Fourier transform infrared spectroscopy

An ex vivo case series aimed at identification of normal laryngeal tissue from laryngeal epidermoid squamous keratinized carcinoma by measuring laser-induced autofluorescence (LIAF) and Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectra is presented. The case series results were obtained for paired samples extracted from three patients (exclusion: macroscopic changes of normal vocal cord observed during surgery; surgical intervention on vocal cord, treated only with chemotherapy or radiotherapy for carcinoma; inclusion: men, aged 57-68, non-smokers). For LIAF analysis, a 375-nm picosecond pulsed laser diode with 31 MHz pulse repetition rate, 100 ps full-time width at half-maximum, and average power 0.49 μW was used. LIAF and FTIR-ATR spectra show noticeable differences between normal and malignant tissues. LIAF spectra differed in shape of emitted band, peak position, and band relative intensity of the two kinds of samples, evidencing hypsochromic shift and mean fluorescence intensity decrease of (75.42 ± 3)% in malignant tissue with respect to the normal one. The lack of 1745 cm^-1 band in FTIR-ATR spectra for malignant tissues could be considered an important indicative of the presence of this kind of tissue; moreover, it resulted a greater contribution of lipids and proteins in normal tissue and of collagen in malignant tissue. Penetration depth of the evanescent wave was about 2 μm at an angle of 42°. The two spectroscopic methods are complementary, are applicable for real-time measurements, and may enhance cancer detection and diagnostics. Results presented in this study evidence the potential of the two methods for future in vivo studies.

Detection accuracy for epithelial dysplasia using an objective autofluorescence visualization method based on the luminance ratio

The autofluorescence visualization method (AVM) uses blue excitation light to assist in the diagnosis of epithelial dysplasia. It detects epithelial dysplasia as a black area, which is known as fluorescence visualization loss (FVL). In this study, we evaluated the detection accuracy for epithelial dysplasia of the tongue using the objective AVM and assessed its possible clinical utility. Seventy-nine tongue specimens clinically suspected to have leukoplakia or squamous cell carcinoma (SCC) were analyzed. First, the AVM was subjectively performed using the Visually Enhanced Lesion scope (VELscope), and the iodine-staining method was then performed. After biopsy, the histopathological results and the luminance ratio between the lesion and healthy tissue were compared, and a receiver operating characteristic curve was created. The cutoff value for the objective AVM was determined; the lesion was considered FVL-positive or -negative when the luminance ratio was higher or lower than the cutoff value, respectively. The histopathological diagnoses among the 79 specimens were SCC (n=30), leukoplakia with dysplasia (n=34), and leukoplakia without dysplasia (n=15). The cutoff value of the luminance ratio was 1.62, resulting in 66 FVL-positive and 13 FVL-negative specimens. The luminance ratio was significantly higher in the epithelial dysplasia-positive than -negative group (P<0.000 1). The objective AVM showed much higher consistency between histopathological results than did the two methods (kappa statistic=0.656). In conclusion, objective autofluorescence visualization has a potential as an auxiliary method for diagnosis of epithelial dysplasia.

Optical redox ratio and endogenous porphyrins in the detection of urinary bladder cancer: A patient biopsy analysis

Bladder cancer is among the most common cancers in the UK and conventional detection techniques suffer from low sensitivity, low specificity, or both. Recent attempts to address the disparity have led to progress in the field of autofluorescence as a means to diagnose the disease with high efficiency, however there is still a lot not known about autofluorescence profiles in the disease. The multi-functional diagnostic system "LAKK-M" was used to assess autofluorescence profiles of healthy and cancerous bladder tissue to identify novel biomarkers of the disease. Statistically significant differences were observed in the optical redox ratio (a measure of tissue metabolic activity), the amplitude of endogenous porphyrins and the NADH/porphyrin ratio between tissue types. These findings could advance understanding of bladder cancer and aid in the development of new techniques for detection and surveillance.

Influence of hematuria and infection on diagnostic accuracy of urinary LASP1: a new biomarker for bladder carcinoma

AIM

To further promote the clinical use of urinary LASP1 as biomarker for urothelial carcinoma of the bladder regarding limitations and alternative testing systems.

PATIENTS & METHODS

Urine stabilization, alternative measurement systems and limitations by erythrocyte contamination and infection were investigated in 246 patients.

RESULTS

Thimerosal allowed sufficient stabilization. Fluorescence-activated cell sorting analysis was not influenced by presence of erythrocytes or leukocytes and reliably urothelial carcinoma of the bladder but cell counts in specimen were low. Cut-off values of <25 leukocytes and <200 erythrocytes/µl resulted in sensitivity, specificity, positive and negative predictive values of 0.59, 0.80, 0.80 and 0.59, respectively.

CONCLUSION

Hematuria up to 200 erythrocytes/µl but not presence of leukocytes may be tolerated for this promising marker.

Changes in autofluorescence based organoid model of muscle invasive urinary bladder cancer

Muscle invasive urinary bladder cancer is one of the most lethal cancers and its detection at the time of transurethral resection remains limited and diagnostic methods are urgently needed. We have developed a muscle invasive transitional cell carcinoma (TCC) model of the bladder using porcine bladder scaffold and the human bladder cancer cell line 5637. The progression of implanted cancer cells to muscle invasion can be monitored by measuring changes in the spectrum of endogenous fluorophores such as reduced nicotinamide dinucleotide (NADH) and flavins. We believe this could act as a useful tool for the study of fluorescence dynamics of developing muscle invasive bladder cancer in patients. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.