Molecular histopathology of matrix proteins through autofluorescence super-resolution microscopy.

Extracellular matrix diseases like fibrosis are elusive to diagnose early on, to avoid complete loss of organ function or even cancer progression, making early diagnosis crucial. Imaging the matrix densities of proteins like collagen in fixed tissue sections with suitable stains and labels is a standard for diagnosis and staging. However, fine changes in matrix density are difficult to realize by conventional histological staining and microscopy as the matrix fibrils are finer than the resolving capacity of these microscopes. The dyes further blur the outline of the matrix and add a background that bottlenecks high-precision early diagnosis of matrix diseases. Here we demonstrate the multiple signal classification method-MUSICAL-otherwise a computational super-resolution microscopy technique to precisely estimate matrix density in fixed tissue sections using fibril autofluorescence with image stacks acquired on a conventional epifluorescence microscope. We validated the diagnostic and staging performance of the method in extracted collagen fibrils, mouse skin during repair, and pre-cancers in human oral mucosa. The method enables early high-precision label-free diagnosis of matrix-associated fibrotic diseases without needing additional infrastructure or rigorous clinical training.

Fibroblastic osteosarcoma: A perplexing entity.

Osteosarcoma (OS), also referred to as osteogenic sarcoma, is the most common primary malignant tumour affecting long bones, characterised by the proliferation of osteoblastic precursor cells and the production of osteoid or immature bone. OSs of the head and neck region have unique biology, exhibiting a clinical behaviour and a natural history that are distinct from OSs of the trunk and extremities. Similarly, their radiological appearance and histological growth pattern can be quite diverse proving to be a challenge to histopathologists to arrive at a diagnosis. Hence, OSs of the jaw remain enigmatic, and a number of difficulties related to their diagnosis and treatment are yet to be resolved. This article reports on a case of advanced OS of the mandible in a 45-year-old woman who came for the evaluation of swelling. This case illustrates the various modalities of diagnosis, such as radiology, histopathology and immunohistochemistry for the confirmation of the variants of OS, leading to an enormously improved quality of life by offering an improved opportunity for cure and treatment.

Portable, handheld, and affordable blood perfusion imager for screening of subsurface cancer in resource-limited settings.

Precise information on localized variations in blood circulation holds the key for noninvasive diagnostics and therapeutic assessment of various forms of cancer. While thermal imaging by itself may provide significant insights on the combined implications of the relevant physiological parameters, viz. local blood perfusion and metabolic balance due to active tumors as well as the ambient conditions, knowledge of the tissue surface temperature alone may be somewhat inadequate in distinguishing between some ambiguous manifestations of precancer and cancerous lesions, resulting in compromise of the selectivity in detection. This, along with the lack of availability of a user-friendly and inexpensive portable device for thermal-image acquisition, blood perfusion mapping, and data integration acts as a deterrent against the emergence of an inexpensive, contact-free, and accurate in situ screening and diagnostic approach for cancer detection and management. Circumventing these constraints, here we report a portable noninvasive blood perfusion imager augmented with machine learning-based quantitative analytics for screening precancerous and cancerous traits in oral lesions, by probing the localized alterations in microcirculation. With a proven overall sensitivity >96.66% and specificity of 100% as compared to gold-standard biopsy-based tests, the method successfully classified oral cancer and precancer in a resource-limited clinical setting in a double-blinded patient trial and exhibited favorable predictive capabilities considering other complementary modes of medical image analysis as well. The method holds further potential to achieve contrast-free, accurate, and low-cost diagnosis of abnormal microvascular physiology and other clinically vulnerable conditions, when interpreted along with complementary clinically evidenced decision-making perspectives.

Collagen deposition correlates with loss of E-cadherin and increased p63 expression in dysplastic conditions of oral submucous fibrosis.

This paper focuses on the status of epithelial markers, E-cadherin, and p63 in the backdrop of an abnormal amount of collagen in the sub-mucosa of dysplastic and non-dysplastic grades of OSF. Histologically confirmed OSF and normal oral mucosa samples were procured. Samples were stained by Van Gieson's stain (VG) and immunohistochemistry. The captured images were analyzed by ImageJ software to quantify their grayscale intensities. There was a gradual increase in the intensity of VG stain from normal to non-dysplastic and dysplastic OSF and the differences in their mean grayscale values were found to be significant (p < 0.00001). The intensity of E-cadherin was found to be the highest in non-dysplastic conditions and lowest in dysplastic conditions. The intensity difference of E-cadherin between normal and non-dysplastic OSF was found to be significant (p < 0.00001). The grayscale scale intensity values for p63 in whole epithelium depicted significant differences between normal and diseased conditions but for its intensity, in basal cells, significant differences were found between non-dysplastic and other classes of tissues. There was a positive correlation observed between VG and p63 staining intensity. The diseased oral epithelium demonstrated greater deposition of sub-epithelial collagen fibers along with subsequent loss of E-cadherin and an increased p63 expression.

Comprehensive Evaluation of PAXgene Fixation on Oral Cancer Tissues Using Routine Histology, Immunohistochemistry, and FTIR Microspectroscopy.

The choice of tissue fixation is critical for preserving the morphology and biochemical information of tissues. Fragile oral tissues with lower tensile strength are challenging to process for histological applications as they are prone to processing damage, such as tissue tear, wrinkling, and tissue fall-off from slides. This leads to loss of morphological information and unnecessary delay in experimentation. In this study, we have characterized the new PAXgene tissue fixation system on oral buccal mucosal tissue of cancerous and normal pathology for routine histological and immunohistochemical applications. We aimed to minimize the processing damage of tissues and improve the quality of histological experiments. We also examined the preservation of biomolecules by PAXgene fixation using FTIR microspectroscopy. Our results demonstrate that the PAXgene-fixed tissues showed significantly less tissue fall-off from slides. Hematoxylin and Eosin staining showed comparable morphology between formalin-fixed and PAXgene-fixed tissues. Good quality and slightly superior immunostaining for cancer-associated proteins p53 and CK5/6 were observed in PAXgene-fixed tissues without antigen retrieval than formalin-fixed tissues. Further, FTIR measurements revealed superior preservation of glycogen, fatty acids, and amide III protein secondary structures in PAXgene-fixed tissues. Overall, we present the first comprehensive evaluation of the PAXgene tissue fixation system in oral tissues. This study concludes that the PAXgene tissue fixation system can be applied to oral tissues to perform diagnostic molecular pathology experiments without compromising the quality of the morphology or biochemistry of biomolecules.

Pathophysiological relationship between hypoxia associated oxidative stress, Epithelial-mesenchymal transition, stemness acquisition and alteration of Shh/ Gli-1 axis during oral sub-mucous fibrosis and oral squamous cell carcinoma.

Oral sub-mucous fibrosis (OSF) is a pathophysiological state of oral cavity or oropharynx having a high chance of conversion to oral squamous cell carcinoma (OSCC). It involves fibrotic transformation of sub-epithelial matrix along with epithelial abnormalities. The present work aims to unveil the mechanistic domain regarding OSF to OSCC conversion exploring the scenario of hypoxia associated oxidative stress, epithelial-mesenchymal transition (EMT), metastasis and stemness acquisition. The study involves histopathological analysis of the diseased condition along with the exploration of oxidative stress status, assessment of mitochondrial condition, immunohistochemical analysis of HIF-1α, E-cadherin, vimentin, ERK, ALDH-1, CD133, Shh, Gli-1 and survivin expressions in the oral epithelial region together with the quantitative approach towards collagen deposition in the sub-epithelial matrix. Oxidative stress was found to be associated with type-II EMT in case of OSF attributing the development of sub-epithelial fibrosis and type-III EMT in case of OSCC favoring malignancy associated metastasis. Moreover, the acquisition of stemness during OSCC can also be correlated with EMT. Alteration of Shh and Gli-1 expression pattern revealed the mechanistic association of hypoxia with the phenotypic plasticity and disease manifestation in case of OSF as well as OSCC. Shh/ Gli-1 signaling can also be correlated with survivin mediated cytoprotective phenomenon under oxidative stress. Overall, the study established the correlative network of hypoxia associated oxidative stress, EMT and manifestation of oral pre-cancerous and cancerous condition in a holistic approach that may throw rays of hope in the therapeutic domain of the concerned diseases.

Multifractal Alterations in Oral Sub-Epithelial Connective Tissue During Progression of Pre-Cancer and Cancer.

Bright-field microscopy (BFM) encrypts the optical transillumination profile of the transmitted light attenuated by the complex micro-structural tissue convolutions, manifested by the dense and compact regions of the specimen under examination. The connotations of idiosyncratic tissue interaction dynamics with the onset of pre-cancerous activity are encoded in the BFM acquired oral mucosa histopathological images (OMHI). In the present study, our analysis is focused on the sub-epithelium region of the oral mucosa, which has high clinical significance but sparsely explored in the literature from the textural domain. Histopathology being the gold-standard technique till date, we have used the light microscopic histopathology images for tissue characterization. The tissue-index transmission patches (TITP) from the sub-epithelium region are cropped under the guidance of oral onco-pathologists. After that, the TITPs are characterized for its multi-scale spatial-deformation dynamics, while keeping the intrinsic anisotropic geometry, and local contour connectivity within tolerable limits. With recent studies exhibiting multifractal's potency in diverse biological system analysis, here, we exploit the 2D multifractal detrended fluctuation analysis (2D-MFDFA) on TITPs for exploring a discriminative set of multifractal signatures for healthy, oral potentially malignant disorders and oral cancer tissue sample. The predictive model's competency is validated on an experimentally collected corpus of TITP samples and substantiated via confirmatory data statistics and analysis, showing its inter-class segregation efficacy. Moreover, the 2D-MFDFA analysis evinces the complex multifractal patterns in TITPs, which is due to the presence of composite long-range correlations in the oral mucosa tissue fabric.

Epithelial Distribution of E-Cadherin, p63, and Mitotic Figures in ApoTome Images to Determine the Oncogenic Potentiality of Oral Submucous Fibrosis.

The exact process of the malignant conversion of oral submucous fibrosis (OSF) to oral cancer is not fully understood. This study aimed to detect and analyze E-cadherin expression, p63 expression, and number of mitotic figures, all correlated to cancer development, in ApoTome images of oral tissues to determine the oncogenic potentiality of OSF. ApoTome images of the study groups (6 normal, 16 OSF with dysplasia, and 10 OSF without dysplasia) were recorded. Cytoplasmic and membranous E-cadherin expression, breakages of the cell membrane, and p63 expression were detected in MATLAB 2016b. The number of mitotic figures detected by MATLAB was correlated with the number of chromosomes detected by ImageJ. A Mann­Whitney U test was done to determine a significant difference between the study groups for cytoplasmic and membranous E-cadherin distribution points. Statistical significant differences were found for cytoplasmic E-cadherin distribution between normal and OSF (with dysplasia) (p = 0.0278). There was an increase in mitotic figures, p63 expression, and cytoplasmic E-cadherin expression and a decrease in membranous E-cadherin expression from normal to diseased condition. Hence, automated detection and quantification of E-cadherin, p63, and mitotic figures in ApoTome images of oral biopsies can help in determining the oncogenic potentiality of OSF.

Malignant potentiality assessment of oral submucous fibrosis through semi-quantitative approach.

BACKGROUND: In the context of early diagnosis and prevention of oral cancer, precise assessment of malignant potentiality of the oral potentially malignant disorders, particularly oral submucous fibrosis (OSF) is crucial. Till date, the assessment of malignant potentiality suffers from predictive ambiguity due to the lack of precision in the gold standard techniques. This can be addressed by integrating heuristic domain knowledge with quantitative analysis. AIM: The aim of this study is to propose an index for enhancing accuracy in malignant potentiality evaluation. MATERIALS AND METHODS: The present study analyzes important histomorphometric attributes (epithelial thickness, basal cell nuclear size, nuclear-to-cytoplasmic area ratio of basal cells, chromaticity of basal cell nucleus, thickness of basement membrane, ratio of vasculature in juxta-epithelial connective tissue [i.e., area covered by blood vessels/total area], collagen density in the lamina propria) of oral mucosa in dysplastic and nondysplastic OSF in association with relevant oncopathological appreciations (weightage of different features as suggested by oral pathologists) toward proposing a "Malignant Potentiality Index" (MPI). RESULTS: Analysis of variance and notch box plot analysis depict statistically significant differences (P < 0.0001) in the histopathological features among different study groups (normal oral mucosa, OSF without dysplasia, OSF with dysplasia). Histopathological observation of one OSF patient with calculated MPI is shown. CONCLUSION: This newly proposed diagnostic cum prognostic decision-making parameter, the "MPI" may bring a value addition to the conventional diagnostic gold standard.

A miscellany of cribriform pattern, squamous metaplasia and clear cells in pleomorphic adenoma of upper lip: A diagnostic paradox.

Pleomorphic Adenoma (PA), a benign neoplasm of glandular origin most commonly involves major salivary glands. It is rare in minor salivary glands such as hard palate, upper lip and buccal mucosa, frequently affecting middle aged females. PA comprises diverse histopathologic features of epithelial, myoepithelial and mesenchymal components. Aberrant histopathologic features in Pleomorhic Adenoma thus calls for judicious discrimination from alike entities which facilitates appropriate surgical management. Here we present a case report of PA in upper lip in a 25 year old female patient showing uncommon findings like clear cells, squamous metaplasia and cribriform pattern.

Rhabdomyosarcoma involving maxilla mimicking gingival enlargement: A diagnostic challenge.

Rhabdomyosarcoma (RMS) is a rare, rapidly growing, highly aggressive malignant neoplasm, originating from undifferentiated mesenchymal cells that retain their ability to differentiate into skeletal muscle. It mainly affects children, accounts for <1% of all adult malignancies and has varied clinical presentations. The head and neck region accounts for 35%-40% of all RMS cases, of which 10%-12% cases involve the oral cavity. This report deals with a case of RMS in a 40-year-old woman, primarily involving maxillary gingiva for which she underwent excision with subsequent recurrences. The uniqueness of this case is that it reminds us of the essential clinical dictum that 'every growth we encounter, no matter how benign it appears clinically, should be looked upon with suspicion'. Hence, proper integration of history, clinical examination and investigation is required to reach a correct diagnosis enabling early treatment, thereby preventing functional and aesthetic loss and psychological trauma.

Elucidation of Differential Nano-Textural Attributes for Normal Oral Mucosa and Pre-Cancer.

Computational analysis on altered micro-nano-textural attributes of the oral mucosa may provide precise diagnostic information about oral potentially malignant disorders (OPMDs) instead of an existing handful of qualitative reports. This study evaluated micro-nano-textural features of oral epithelium from scanning electron microscopic (SEM) images and the sub-epithelial connective tissue from light microscopic (LM) and atomic force microscopic (AFM) images for normal and OPMD (namely oral sub-mucous fibrosis, i.e., OSF). Objective textural descriptors, namely discrete wavelet transform, gray-level co-occurrence matrix (GLCM), and local binary pattern (LBP), were extracted and fed to standard classifiers. Best classification accuracy of 87.28 and 93.21%; sensitivity of 93 and 96%; specificity of 80 and 91% were achieved, respectively, for SEM and AFM. In the study groups, SEM analysis showed a significant (p < 0.01) variation for all the considered textural descriptors, while for AFM, a remarkable alteration (p < 0.01) was only found in GLCM and LBP. Interestingly, sub-epithelial collagen nanoscale and microscale textural information from AFM and LM images, respectively, were complementary, namely microlevel contrast was more in normal (0.251) than OSF (0.193), while nanolevel contrast was more in OSF (0.283) than normal (0.204). This work, thus, illustrated differential micro-nano-textural attributes for oral epithelium and sub-epithelium to distinguish OPMD precisely and may be contributory in early cancer diagnostics.

Segmentation and analysis of surface characteristics of oral tissues obtained by scanning electron microscopy to differentiate normal and oral precancerous condition.

Abnormal epithelial stratification is a sign of oral dysplasia and hence evaluation of surface characteristics of oral epithelial region can help in detection of cancerous progression. Surface characteristics can be better visualised by Scanning Electron Microscopy (SEM) in comparison to light microscopy. In our study we have developed automated image processing algorithms i.e. Gaussian with median filtering and Gradient filtering, using MATLAB 2016b, to segment the surface characteristics i.e. the ridges and pits in the SEM images of oral tissue of normal (13 samples) and Oral Submucous Fibrosis (OSF) (36 samples) subjects. After segmentation, quantitative measurement of the parameters like area, thickness and textural features like entropy, contrast and range filter of ridges as well as area of pit and the ratio of area of ridge vs. area of pit was done. Statistical significant differences were obtained in between normal and OSF study groups for thickness (p=0.0107), entropy (p<0.00001) and contrast of ridge (p<0.00001) for Gaussian with median filtering and for all the parameters except thickness of the ridge(p=1.386), for Gradient filtering. Thus, computer aided image processing by Gradient filter followed by quantitative measurement of the surface characteristics provided precise differentiation between normal and precancerous oral condition.

Genome-wide miRNA methylome analysis in oral cancer: possible biomarkers associated with patient survival.

AIM: The methylome associated with miRNA loci was investigated in oral cancer to explore tobacco specific methylation and potential biomarkers for patient survival. METHODS: Methylome data was generated from 16 pairs of cancer-normal tissues by reduced representation bisulfite sequencing method. Differentially methylated regions were identified using the DMAP pipeline. In silico validation and Kaplan-Meier survival analyses were performed on The Cancer Genome Atlas data based on our miRNA methylome data. RESULTS: A total of 4310 unique differentially methylated regions, mapping to 144 miRNA loci, were identified. Three distinct groups of miRNAs were differentially methylated in cancer tissues from smokers, chewers and mixed habitués. Hypermethylation of miR-503, miR-200a/b, miR-320b and miR-489 was associated with worse 5-year survival. CONCLUSION: Differential methylation patterns in miRNA loci are associated with poor survival underscoring their potential as predictive and prognostic biomarkers in oral cancer.

Langerhans Cell Histiocytosis in an Adult with Oral Cavity Involvement: Posing a Diagnostic Challenge.

Langerhans cell histiocytosis (LCH) is a rare hematological disorder characterized by local or generalized, uncontrolled proliferation and infiltration of Langerhans type of histiocytic cells. It represents a spectrum of clinicopathologic disorders, ranging from a highly aggressive and frequently fatal multisystem disease to an easily cured solitary lesion of bone. Involvement of children and the younger age group is more common than the adults. Oral cavity involvement occurs early in LCH, but the initial symptoms are generally nonspecific, often causing misdiagnosis. This report describes a rare case of chronic localized LCH in an adult patient, with involvement of oral cavity. A 34-year-old male patient presented with multiple nodulo-papular, ulcerated lesions in gingiva involving both the jaws (primarily mandible) and the left buccal mucosa, in addition to regional teeth mobility. The most striking feature was that even after extraction of mobile teeth, the lesions persisted. After recording proper history, performing clinical and radiological evaluation, an incisional biopsy was performed followed by histopathology and immunohistochemistry to reach a confirmatory diagnosis of LCH, thereby implementing early and appropriate initiation of treatment.

Clinical, radiological and histological features of an unique case of calcifying epithelial odontogenic tumor.

Calcifying epithelial odontogenic tumor (CEOT), also known as Pindborg tumor, is a rare benign but locally aggressive odontogenic neoplasm, accounts for <1% of all odontogenic tumors. CEOT is usually seen in the posterior area of the mandible in-between 30 and 50 years of age without definite sex predilection. A painless, slow-growing swelling with bone expansion is the most common clinical feature of CEOT. Radiographically, it presents as a mixed radiographic lesion may or may not be associated with any impacted tooth. Confirmation of the diagnosis is made by histopathological examination. The tumor has a recurrence rate of 10%-20% and so periodic follow-up is necessary. A unique case of CEOT involving the right mandibular molar-premolar in a 25-year-old female patient with clinical behavior, radiological, histopathological features and surgical managements is discussed herewith.

Endorsing cellular competitiveness in aberrant epithelium of oral submucous fibrosis progression: neighbourhood analysis of immunohistochemical attributes.

Epithelial abnormality during the transformation of oral submucous fibrosis (OSF) into oral squamous cell carcinoma has been well studied and documented. However, the differential contribution of atrophy and hyperplasia for malignant potentiality of OSF is yet to be resolved. Existing diagnostic conjectures lack precise diagnostic attributes which may be effectively resolved by substantiation of specific molecular pathology signatures. Present study elucidates existence of cellular competitiveness in OSF conditions using computer-assisted neighbourhood analysis in quantitative immunohistochemistry (IHC) framework. The concept of field cancerization was contributory in finding correspondence among neighbouring cells of epithelial layers with reference to differential expression of cardinal cancer-related genes [c-Myc (oncogene), p53 (tumour suppressor), and HIF-1α (hypoxia regulator)] which are known to be important sensors in recognizing cellular competitive interface. Our analyses indicate that different states of OSF condition may be associated with different forms of competitiveness within epithelial neighbouring cells which might be responsible to shape the present and future of the pre-malignant condition. Analytical findings indicated association of atrophic epithelium with stress-driven competitive environment having low c-Myc, high-p53, and stable HIF-1α (the looser cells) which undergo apoptosis. Whereas, the cells with high c-Myc+ (winner cells) give rise to hyperplastic epithelium via possible mutation in p53. The epithelial dysplasia plausibly occurs due to clonal expansion of c-Myc and p53 positive supercompetitor cells. Present study proposes quantitative IHC along with neighbourhood analysis which might help us to dig deeper on to the interaction among epithelial cell population to provide a better understanding of field cancerization and malignant transformation of pre-malignancy.

Detailed account on activation mechanisms of ruthenium coordination complexes and their role as antineoplastic agents.

Ruthenium (Ru) complexes are known for their promising anticancer activity presumably due to octahedral coordination geometry, slow ligand exchange rate, the range of different oxidation states and target specificity. This review article summarizes the physicochemical processes which are responsible for the selectivity of Ru complexes toward cancer cells over the normal cells. Emphasis has been given on the activation mechanism of Ru(III) complex administered as a prodrug and then the release of active species in an acidic environment of cancer cell through normal or photo induced hydrolysis or ligand oxidation. This article also elaborates how active Ru complex can be designed by their rate of hydrolysis, kinetics of ligand exchange, pKa of the aquated species. The article further articulates how Ru complexes inhibit tumor growth via multiple events such as transferrin/albumin binding, ROS generation, inhibition of glutathione-S-transferases and kinases and DNA intercalation. Based on the above understanding, examples of various Ru complexes with their in-vitro cell based cytotoxicity and mechanism of action have been described to make this review comprehensive for future Ru based anticancer drug development. In the end, comments have been made on some emerging concepts regarding lack of innertness of Ru(III) complexes vis-à-vis Ru(II) species.