Interpretation and quantification of immunostains

Cytokine Levels in Experimental Branch Retinal Vein Occlusion Treated With Either Bevacizumab or Triamcinolone Acetonide

Purpose

To compare gene expression changes following branch retinal vein occlusion (BRVO) in the pig with and without bevacizumab (BEV) and triamcinolone acetonide (TA).

Methods

Photothrombotic BRVOs were created in both eyes of four groups of nine pigs (2, 6, 10, and 20 days). In each group, six pigs received intravitreal injections of BEV in one eye and TA in the fellow eye, with three pigs serving as untreated BRVO controls. Three untreated pigs served as healthy controls. Expression of mRNA of vascular endothelial growth factor (VEGF), glial fibrillary acidic protein (GFAP), dystrophin (DMD), potassium inwardly rectifying channel subfamily J member 10 protein (Kir4.1, KCNJ10), aquaporin-4 (AQP4), stromal cell-derived factor-1α (CXCL12), interleukin-6 (IL6), interleukin-8 (IL8), monocyte chemoattractant protein-1 (CCL2), intercellular adhesion molecule 1 (ICAM1), and heat shock factor 1 (HSF1) were analyzed by quantitative reverse-transcription polymerase chain reaction. Retinal VEGF protein levels were characterized by immunohistochemistry.

Results

In untreated eyes, BRVO significantly increased expression of GFAP, IL8, CCL2, ICAM1, HSF1, and AQP4. Expression of VEGF, KCNJ10, and CXCL12 was significantly reduced by 6 days post-BRVO, with expression recovering to healthy control levels by day 20. Treatment with BEV or TA significantly increased VEGF, DMD, and IL6 expression compared with untreated BRVO eyes and suppressed BRVO-induced CCL2 and AQP4 upregulation, as well as recovery of KCNJ10 expression, at 10 to 20 days post-BRVO.

Conclusions

Inflammation and cellular osmohomeostasis rather than VEGF suppression appear to play important roles in BRVO-induced retinal neurodegeneration, enhanced in both BEV- and TA-treated retinas.

Translational Relevance

Inner retinal neurodegeneration seen in this acute model of BRVO appears to be mediated by inflammation and alterations in osmohomeostasis rather than VEGF inhibition, which may have implications for more specific treatment modalities in the acute phase of BRVO.

Review of immunohistochemistry techniques: Applications, current status, and future perspectives

The Hematoxylin and Eosin stain is a cornerstone in histopathology that facilitates the microscopic examination of tissue samples for identifying infections and tumors. However, challenges arise from the similar appearances of diseases and cells, prompting the emergence of Immunohistochemistry (IHC) as an important technique. This review summarizes the principles, procedures, and applications and future perspectives of IHC, a prevalent immunostaining method allowing the detection of specific proteins in tissue sections. The multistep IHC process involves fixation, embedding, sectioning, antigen retrieval, blocking, detection, counterstaining, mounting, and visualization, with interpretation relying on factors such as microanatomic distribution and staining intensity. Common errors in IHC such as non-specific staining, tissue artifacts, inadequately inactivation of endogenous peroxidase activity and cross-reactivity, can substantially affect the accuracy and reliability of results, thereby impacting the interpretation of biological findings. Serving diagnostic, prognostic, predictive, and therapeutic roles in various conditions, including tumors, infectious diseases, neurodegenerative disorders, and muscle diseases, IHC remains pivotal despite its intricate nature. The adoption of digital pathology emerges as a progressive enhancement, addressing limitations and ensuring more accurate analyses in histopathology.

Walking a thin line between fixation and epitope binding - characterization of antigen retrieval methods suitable for eosinophil and HSV-2 staining in formalin-fixed female reproductive tissue

Antibody-based fluorescence analysis of female reproductive tissues in research of sexually transmitted diseases allows for an in-depth understanding of protein localization, interactions, and pathogenesis. However, in many cases, cryosectioning is not compatible with biosafety regulations; at all times, exposure of lab personnel and the public to potentially harmful pathogens from biological infectious material must be avoided; thus, formaldehyde fixation is essential. Due to formaldehyde's cross-linking properties, protein detection with antibodies can be impeded. To allow effective epitope binding during immunofluorescence of formalin-fixed paraffin-embedded vaginal tissue, we investigated two antigen retrieval methods. We tested these methods regarding their suitability for automated image analysis, facilitating reproducible quantitative microscopic data acquisition in sexually transmitted disease research. Heat-based retrieval at 80°C in citrate buffer proved to increase antibody binding to eosinophil protein and HSV-2 visibly and tissue morphology best, and was the most efficient for sample processing and quantitative analysis.

OralImmunoAnalyser: a software tool for immunohistochemical assessment of oral leukoplakia using image segmentation and classification models

Oral cancer ranks sixteenth amongst types of cancer by number of deaths. Many oral cancers are developed from potentially malignant disorders such as oral leukoplakia, whose most frequent predictor is the presence of epithelial dysplasia. Immunohistochemical staining using cell proliferation biomarkers such as ki67 is a complementary technique to improve the diagnosis and prognosis of oral leukoplakia. The cell counting of these images was traditionally done manually, which is time-consuming and not very reproducible due to intra- and inter-observer variability. The software presently available is not suitable for this task. This article presents the OralImmunoAnalyser software (registered by the University of Santiago de Compostela-USC), which combines automatic image processing with a friendly graphical user interface that allows investigators to oversee and easily correct the automatically recognized cells before quantification. OralImmunoAnalyser is able to count the number of cells in three staining levels and each epithelial layer. Operating in the daily work of the Odontology Faculty, it registered a sensitivity of 64.4% and specificity of 93% for automatic cell detection, with an accuracy of 79.8% for cell classification. Although expert supervision is needed before quantification, OIA reduces the expert analysis time by 56.5% compared to manual counting, avoiding mistakes because the user can check the cells counted. Hence, the SUS questionnaire reported a mean score of 80.9, which means that the system was perceived from good to excellent. OralImmunoAnalyser is accurate, trustworthy, and easy to use in daily practice in biomedical labs. The software, for Windows and Linux, with the images used in this study, can be downloaded from https://citius.usc.es/transferencia/software/oralimmunoanalyser for research purposes upon acceptance.

Is GRP78 (Glucose-regulated protein 78) a prognostic biomarker in differents types of cancer? A systematic review and meta-analysis

GRP78 is a chaperone with anti-apoptotic function associated with aggressive tumors. This systematic review aimed to evaluate GRP78 expression in cancer and its relation to prognosis outcomes. This review was conducted in different databases searching for human cancer studies assessing GRP78 immunohistochemical levels on tissue samples. A total of 98 manuscripts were included. In 62% of the studies, GRP78 was associated with a worse prognosis. A meta-analysis included 29 studies that detected a significantly higher expression of GRP78 in cancer tissues (RR= 2.35, 95% CI 1.75-3.15) compared to control. A meta-analysis of 3 and 5-years Overall Survival revealed an increased risk of death for tumors with high expression of GRP78 (RR=1.36, 95%CI 1.16-1,59, I² = 57%) and (RR=1.65, 95%CI 1.22-2.21, I² =64%), respectively. GRP78 is an important prognostic biomarker for different types of cancer and a promising therapeutic target.

Intranasal and Intramuscular Immunization with Outer Membrane Vesicles from Serogroup C Meningococci Induced Functional Antibodies and Immunologic Memory

BACKGROUND

Immunization is the key to prevent invasive meningococcal disease (IMD), caused by Neisseria meningitidis. Outer membrane vesicles (OMVs) can be used as meningococcal antigens.

METHODS

Isogenic mice A/Sn (H2^a) were immunized with low antigenic doses of OMVs of an N. meningitidis C:2a:P1.5 strain, via intranasal/intramuscular route, adjuvanted by cholera toxin subunit B (CTB) or via intramuscular route only, adjuvanted by aluminium hydroxide (AH). Mice were followed until old age and humoral and cellular responses were assessed by ELISA, Immunoblotting, Dot-blot, Serum-bactericidal assay, Immunohistochemistry and ELISpot.

RESULTS

OMV+CTB and OMV+AH groups presented statistically higher antibodies titers, which persisted until middle and old ages. IgG isotypes point to a Th2 type of response. Avidity indexes were considered high, regardless of adjuvant use, but only groups immunized with OMVs and adjuvants (OMV+CTB and OMV+AH) presented bactericidal activity. The antibodies recognized antigens of molecular weights attributed to porin and cross-reactivity proteins. Although the spleen of old mice did not present differences in immunohistochemistry marking of CD68+, CD4+, CD79+ and CD25+ cells, splenocytes of immune groups secreted IL-4 and IL-17 when stimulated with OMVs and meningococcal C polysaccharide.

CONCLUSION

We concluded that both adjuvants, CTB and AH, improved the immunogenicity of low doses of OMVs and contributed to a persistent immune response. Even though AH is well established in the vaccinology area, CTB seems to be a promising adjuvant candidate for meningococcal vaccines: it is suitable for mucosal delivery and supports a Th2 type of response. Therefore, OMVs are still a relevant vaccine platform.

On the Cutting Edge of Oral Cancer Prevention: Finding Risk-Predictive Markers in Precancerous Lesions by Longitudinal Studies

Early identification and management of precancerous lesions at high risk of developing cancers is the most effective and economical way to reduce the incidence, mortality, and morbidity of cancers as well as minimizing treatment-related complications, including pain, impaired functions, and disfiguration. Reliable cancer-risk-predictive markers play an important role in enabling evidence-based decision making as well as providing mechanistic insight into the malignant conversion of precancerous lesions. The focus of this article is to review updates on markers that may predict the risk of oral premalignant lesions (OPLs) in developing into oral squamous cell carcinomas (OSCCs), which can logically be discovered only by prospective or retrospective longitudinal studies that analyze pre-progression OPL samples with long-term follow-up outcomes. These risk-predictive markers are different from those that prognosticate the survival outcome of cancers after they have been diagnosed and treated, or those that differentiate between different lesion types and stages. Up-to-date knowledge on cancer-risk-predictive markers discovered by longitudinally followed studies will be reviewed. The goal of this endeavor is to use this information as a starting point to address some key challenges limiting our progress in this area in the hope of achieving effective translation of research discoveries into new clinical interventions.

Immunohistochemistry as a detection tool for ion channels involved in dental pain signaling

Background

Despite advances in pain detection, diagnosis, and management, the prevalence of dental pain is still on the rise. Although dental pain is not directly related to fatal outcomes, the two most common types of dental pain—dental caries and dentin hypersensitivity—have a significant impact on an individual’s quality of life. Understanding the mechanism of the pain pathway is one of the crucial steps in providing better treatment for these patients. Ion channels are critical biomolecules that have been the subject of dental study owing to their roles in the transmission and transduction of external stimuli, as well as in the control and perception of pain. Numerous immunohistochemical (IHC) staining approaches have also been used to identify the many ion channels implicated in peripheral pain signaling in dental pulp.

Highlight

This review highlights the critical steps in IHC and its role in the detection of ion channels involved in the dental pain signaling pathway.

Conclusion

The key ion channels identified using IHC and whose functions have been widely researched in dental tissues are addressed in this review article.

The immunohistochemical profile of basal cell nevus syndrome-associated and sporadic odontogenic keratocysts: a systematic review and meta-analysis

OBJECTIVES

To provide a systematic review of the literature on studies comparing the immunoprofile of nevoid basal cell carcinoma syndrome (BCNS)-associated and sporadic odontogenic keratocysts (OKCs), in order to identify markers that could accurately distinguish the two OKC subtypes.

MATERIALS AND METHODS

We searched MEDLINE/Pubmed, Web of Science, EMBASE via OVID, and grey literature for publications until December 28th, 2019, that compared the immunohistochemical expression of the two OKC subtypes. The studies were qualitatively assessed using the Critical Appraisal Tool for Case Series (Joana Briggs Institute). Sensitivity and specificity, positive and negative likelihood ratio, diagnostic odds ratio and area under the curve, and pooled estimates were calculated, using a random-effects model.

RESULTS

Seventy-one studies were qualitatively analyzed; 61 markers were evaluated in one study and 32 in ≥ 2 studies. Twenty-five studies reported differential expression of 29 markers in the form of higher number of positive cells or greater staining intensity usually in BCNS-associated OKCs. Meta-analysis for bcl-2, Cyclin D1, CD56, CK18, p53, and PCNA showed that none of those markers is distinguishable between BCNS-associated and sporadic OKCs, in a 95% confidence interval. The risk of bias was high in 34 studies, moderate in 22, and low in 15.

CONCLUSIONS

The present systematic review and meta-analysis uncovered that, although several immunohistochemical markers might characterize the OKC phenotype, they cannot discriminate between the BCNS-associated and sporadic OKCs.

CLINICAL RELEVANCE

This study highlighted the requirement for additional screening for markers by immunohistochemistry, preferentially coupled to alternative diagnostic applications such as genomics technologies.

Comparative In Vitro and In Vivo Studies on Feline, Canine, and Human Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine tumor, and most human MCC cases are infected by Merkel cell polyomavirus (MCPyV). However, the underlying pathogeneses of MCC in animals remain unclear. In the present study, newly established cell lines from feline and canine MCC, a MCPyV-positive human MCC cell line, and MCC tissues from 25 cats and 1 dog were examined and compared pathologically. Feline and canine MCCs were composed of tumor cells arranged in trabeculae and solid packets. Twenty out of 25 feline MCC cases (80%) had other proliferative cutaneous lesions, such as carcinoma in situ and squamous cell carcinoma. Among the 25 feline MCC cases, tumor cells were immunopositive for cytokeratins (CKs), including CK5/6 (4/25 cases, 16%), CK7 (5, 20%), CK18 (25, 100%), CK19 (20, 80%), and CK20 (20, 80%). The tumor cells of feline MCC were also immunopositive for synaptophysin (24/25, 96%) and CD56 (22/25, 88%). The tumor cells of canine MCC were immunopositive for CK18, CK19, CK20, and synaptophysin. Cultured feline and canine MCC cells grew in adherent monolayers and exhibited diffuse cytoplasmic immunoreactivity for CKs, whereas human MCC cells grew in suspension and exhibited dot-like cytoplasmic immunoreactivity for CKs. Differences in the distribution of CKs between human and animal MCC may be attributed to cell adhesion propensities. MCPyV genes and antigen were not detected in feline or canine MCC, suggesting a different etiology from human MCC.

Increased ERBB2 Gene Copy Numbers Reveal a Subset of Salivary Duct Carcinomas with High Densities of Tumor Infiltrating Lymphocytes and PD-L1 Expression

Salivary duct carcinoma (SDC) commonly expresses androgen receptor (AR) and HER2, giving rise to treatment implications. SDC may also express programmed-death-ligand-1 (PD-L1), a predictive marker of response to checkpoint inhibitors. PD-L1 can be associated with genomic instability and high density of tumor infiltrating lymphocytes (TILs). Evaluation of HER2 immunohistochemistry (IHC) in SDC is not standardized, and relationships between ERBB2 copy numbers, PD-L1 expression and TILs in SDC are unknown. We evaluated 32 SDCs for HER2, AR and PD-L1 expression (IHC), ERBB2 status (FISH) and TILs (slide review). HER2 was scored with three different systems (breast, gastric, proposed salivary gland). PD-L1 was evaluated with the combined positive score. Most patients were older men, presenting at advanced clinical stage with nodal or distant metastases. During follow-up (mean 5 years, range 6 months to 21 years), 25 of the 32 patients (78%) died of SDC. We propose a HER2 IHC scoring system which accurately predicts underlying ERBB2 amplification or increased copy numbers in SDC. Most tumors had increased ERBB2 copy numbers (19/32 amplification, 6/32 aneusomy), a finding associated with higher TIL densities (p = 0.045) and PD-L1 expression (p = 0.025). Patients with TILs ≥ 40% had better prognoses (Log-Rank p = 0.013), with TILs being favorable prognosticators in univariate analysis (Hazard ratio: 0.18, p = 0.024). A subset of SDCs with increased ERBB2 copy numbers have higher TILs and PD-L1 expression. TILs ≥ 40% are associated with better prognosis.

Pathologic correlates of the magnetization transfer ratio in multiple sclerosis

OBJECTIVE

To identify pathologic correlates of magnetization transfer ratio (MTR) in multiple sclerosis (MS) in an MRI-pathology study.

METHODS

We acquired MTR maps at 3T from 16 fixed MS brains and 4 controls, and immunostained 100 tissue blocks for neuronal neurofilaments, myelin (SMI94), tissue macrophages (CD68), microglia (IBA1), B-lymphocytes, T-lymphocytes, cytotoxic T-lymphocytes, astrocytes (glial fibrillary acidic protein), and mitochondrial damage (COX4, VDAC). We defined regions of interest in lesions, normal-appearing white matter (NAWM), and cortical normal-appearing gray matter (NAGM). Associations between MTR and immunostaining intensities were explored using linear mixed-effects models (with cassettes nested within patients) and interaction terms (for differences between regions of interest and between cases and controls); a multivariate linear mixed-effects model identified the best pathologic correlates of MTR.

RESULTS

MTR was the lowest in white matter (WM) lesions (23.4 ± 9.4%) and the highest in NAWM (38.1 ± 8.7%). In MS brains, lower MTR was associated with lower immunostaining intensity for myelin (coefficient 0.31; 95% confidence interval [CI] 0.07-0.55), macrophages (coefficient 0.03; 95% CI 0.01-0.07), and astrocytes (coefficient 0.51; 95% CI 0.02-1.00), and with greater mitochondrial damage (coefficient 0.31; 95% CI 0.07-0.55). Based on interaction terms, MTR was more strongly associated with myelin in WM (coefficient 1.58; 95% CI 1.09-2.08) and gray matter (GM) lesions (coefficient 0.66; 95% CI 0.13-1.20), and with macrophages (coefficient 1.40; 95% CI 0.56-2.25), astrocytes (coefficient 2.66; 95% CI 1.31-4.01), and mitochondrial damage (coefficient -12.59; 95% CI -23.16 to -2.02) in MS brains than controls. In the multivariate model, myelin immunostaining intensity was the best correlate of MTR (coefficient 0.31; 95% CI 0.09-0.52; p = 0.004).

CONCLUSIONS

Myelin was the strongest correlate of MTR, especially in WM and cortical GM lesions, but additional correlates should be kept in mind when designing and interpreting MTR observational and experimental studies in MS.

Does Diabetes Induce the Vascular Endothelial Growth Factor (VEGF) Expression in Periodontal Tissues? A Systematic Review

Aim: Diabetes and periodontal disease are both chronic pathological conditions linked by several underlying biological mechanisms, in which the inflammatory response plays a critical role, and their association has been largely recognized. Recently, attention has been given to diabetes as an important mediator of vascular endothelial growth factor (VEGF) overexpression in periodontal tissues, by virtue of its ability to affect microvasculature. This review aims to summarize the findings from studies that explored VEGF expression in diabetic patients with periodontitis, compared to periodontally healthy subjects. Materials and Methods: A systematic literature review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A PubMed search of select medical subject heading (MeSH) terms was carried out to identify all studies reporting findings about VEGF expression in periodontal tissues of diabetic patients up to May 2018. The inclusion criteria were studies on VEGF expression in periodontally diseased tissues of diabetic patients compared with nondiabetic subjects, with any method of analysis, and published in the English language. Results: Eight articles met the inclusion criteria. Immunohistochemistry was used in six of the studies, reverse transcriptase polymerase chain reaction (real-time RT-PCR) aiming to quantify mRNA VEGF expression was used in one study, and ELISA analysis was used for one study. Compared with nondiabetic patients, a higher VEGF expression in gingival tissue and gingival crevicular fluid (GCF) samples in diabetic patients with periodontitis was reported. Conclusions: Overall, novel evidence for the VEGF expression within the periodontal tissue of diabetic patients paves the way for further studies on the role of this protein in neovascularization physiology and pathophysiology in microvasculature of the periodontium.

Cell Cycle Regulator p27 Mediates Body Mass Index Effects in Ovarian Cancer in FIGO-stages I-II

BACKGROUND/AIM

The aim of the present study was to evaluate the association between body mass index (BMI), the biomarker p27, and the clinical factors in FIGO-stages I-II ovarian cancer.

PATIENTS AND METHODS

A total of 128 patients with ovarian cancer were included in the study. For testing differences in univariate analyzes we used the Pearson's Chi-square test and the log-rank test. For multivariate analyses the logistic regression and Cox regression models were used with recurrent disease and disease-free survival as endpoints, respectively.

RESULTS

Patients with BMI ≤25 kg/m² had a significantly better 5-year disease-free survival compared with patients with BMI >25 kg/m² in the total series of patients (p=0.008), and in the series of patients (n=77) with non-serous tumors (p=0.047). Patients with p27-positive non-serous tumors had higher survival compared to patients with p27-negative non-serous tumors (p=0.020).

CONCLUSION

The cell cycle regulator p27 mediates BMI effects in ovarian cancer in FIGO-stages I-II.

The Quantitative ER Immunohistochemical Analysis in Breast Cancer: Detecting the 3 + 0, 4 + 0, and 5 + 0 Allred Score Cases

Background and objectives: The currently used immunohistochemical approach in determining the estrogen receptor (ER) positivity of breast cancers (BCs) is inherently subjective and additionally limited by its semi-quantitative nature. The application of software in the analysis of digitized slide images may overcome some of these limitations. However, the utilization of such an approach requires that the entire staining procedure is standardized. Background and objectives: We aimed to establish a procedure for the photometric and morphometric analysis of BC immunohistochemical parameters that can possibly be used for a diagnostic purpose that is in line with the current semi-quantitative scoring system. Materials and Methods: Semi-quantitative analysis of ER-stained tissue sections was performed following the Allred scoring system guidelines. The quantitative analysis was performed in ImageJ software after color deconvolution. The quantitative analysis of 66 cases of invasive lobular BC included: Percent of ER-positive cells, average nuclear coloration intensity, and the quantitative ER score. The percent of ER-positive tumor cells was counted using a standard grid overlay, while optical density (0.0–1.0) was measured within each nucleus at the grid points. Results: A statistical analysis revealed a significant positive correlation (r = 0.886, p < 0.001) between the subjective semi-quantitative and quantitative ER scores, with a large effect size (d = 3.8215). We observed strong statistically significant correlations between individual parameters of the total ER score, percentage of ER-positive nuclei, and color intensity, obtained by the two independent methods. Conclusions: Additionally, besides excluding subjectivity, the up to now unreported cases of 3 + 0, 4 + 0, and 5 + 0 Allred scores were detected only by the application of the proposed quantitative approach.

High-throughput single-molecule RNA imaging analysis reveals heterogeneous responses of cardiomyocytes to hemodynamic overload

BACKGROUND

The heart responds to hemodynamic overload through cardiac hypertrophy and activation of the fetal gene program. However, these changes have not been thoroughly examined in individual cardiomyocytes, and the relation between cardiomyocyte size and fetal gene expression remains elusive. We established a method of high-throughput single-molecule RNA imaging analysis of in vivo cardiomyocytes and determined spatial and temporal changes during the development of heart failure.

METHODS AND RESULTS

We applied three novel single-cell analysis methods, namely, single-cell quantitative PCR (sc-qPCR), single-cell RNA sequencing (scRNA-seq), and single-molecule fluorescence in situ hybridization (smFISH). Isolated cardiomyocytes and cross sections from pressure overloaded murine hearts after transverse aortic constriction (TAC) were analyzed at an early hypertrophy stage (2 weeks, TAC2W) and at a late heart failure stage (8 weeks, TAC8W). Expression of myosin heavy chain β (Myh7), a representative fetal gene, was induced in some cardiomyocytes in TAC2W hearts and in more cardiomyocytes in TAC8W hearts. Expression levels of Myh7 varied considerably among cardiomyocytes. Myh7-expressing cardiomyocytes were significantly more abundant in the middle layer, compared with the inner or outer layers of TAC2W hearts, while such spatial differences were not observed in TAC8W hearts. Expression levels of Myh7 were inversely correlated with cardiomyocyte size and expression levels of mitochondria-related genes.

CONCLUSIONS

We developed a new image-analysis pipeline to allow automated and unbiased quantification of gene expression at the single-cell level and determined the spatial and temporal regulation of heterogenous Myh7 expression in cardiomyocytes after pressure overload.

Major histocompatibility complex class I in the horse (Equus caballus) placenta during pregnancy and parturition

BACKGROUND

Major histocompatibility protein class I (MHC-I) is believed to be expressed in the horse allantochorion only in limited areas at limited times. However, its expression has only been investigated in early pregnancy with non-quantitative techniques that cannot reliably detect small amounts of protein.

OBJECTIVE

To quantify the relative expression of MHC-I in the allantochorion and endometrium during days 90-240 of pregnancy (PREG), parturition with physiological delivery of fetal membranes (PHYS), and parturition with retention of these membranes (FMR). Also, to visualize protein expression and determine whether classical or non-classical MHC-I mRNA is expressed.

ANIMALS

Heavy draft horses.

SETTING

PREG horses (n = 12) were sampled postmortem at a slaughterhouse. PHYS (n = 6) and FMR (n = 5) horses were sampled at farms in the vicinity of Olsztyn, Poland.

METHODS

For relative quantification of MHC-I, western blotting with densitometry was used. To visualize MHC-I, immunohistochemistry was used. For mRNA identification, RT-PCR was performed.

RESULTS

Although the quantity of MHC-I was lower during PREG than parturition, it was present in the allantochorion and endometrium during PREG. During parturition, MHC-I expression was upregulated in the allantochorion (PHYS vs. PREG: 2.7-times higher, 95% confidence interval, 1.3- to 5.7-times higher; FMR vs. PREG: 3.2-times higher, 95% confidence interval, 1.5- to 6.7-times higher). At parturition, staining for MHC-I was detected in the microcotyledons. Classical and non-classical MHC-I were expressed in both tissues during PREG, PHYS, and FMR.

CONCLUSION

MHC-I protein is present in the horse allantochorion and endometrium for at least the first two-thirds of pregnancy and at parturition.

BAP1 acts as a tumor suppressor in intrahepatic cholangiocarcinoma by modulating the ERK1/2 and JNK/c-Jun pathways

Current therapeutic options for intrahepatic cholangiocarcinoma (ICC) are very limited, which is largely attributed to poor understanding of molecular pathogenesis of ICC. Breast cancer type 1 susceptibility protein-associated protein-1 (BAP1) has been reported to be a broad-spectrum tumor suppressor in many tumor types, yet its role in ICC remains unknown. The aim of this study was to investigate the clinical implications and biological function of BAP1 in ICC. Our results showed that the messenger RNA and protein levels of BAP1 were significantly downregulated in ICC versus paired non-tumor tissues. Overexpression of wild-type but not mutant BAP1 significantly suppressed ICC cell proliferation, cell cycle progression, and invasion in vitro, as well as tumor progression in vivo. Conversely, knockdown of BAP1 yielded opposing effects. Mechanistically, BAP1 functioned as a tumor suppressor in ICC by inhibiting the extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase/c-Jun pathways, and this function was abolished by inactivating mutations. Clinically, low BAP1 expression was positively correlated with aggressive tumor characteristics, such as larger tumor size, presence of lymphatic metastasis, and advanced tumor node metastasis stage. Survival analysis revealed that low BAP1 expression was significantly and independently associated with poor overall survival and relapse-free survival after curative surgery. In conclusion, BAP1 is a putative tumor suppressor of ICC, and may serve as a valuable prognostic biomarker as well as potential therapeutic target for ICC.

Clinical significance of growth factor receptor EGFR and angiogenesis regulator VEGF‑R2 in patients with ovarian cancer at FIGO stages I-II

The aim of the present retrospective cohort study was to investigate the prognostic effect of epidermal growth factor receptor (EGFR) and the angiogenesis regulator vascular endothelial growth factor receptor 2 (VEGF‑R2) on disease-free survival (DFS) rate and recurrent disease, and their association with clinicopathological characteristics in 131 patients with International Federation of Gynecology and Obstetrics (FIGO) stages I-II epithelial ovarian cancer. The techniques of tissue microar-rays and immunohistochemistry were used for the positive detection of the markers. The frequency of positive staining in tumors for EGFR was 24% and for VEGF‑R2 was 77%. Across the cohort, there was a total of 34/131 recurrences (26%) and the 5‑year DFS rate was 68%. In a multivariate logistic regression analysis with recurrent disease as the endpoint, FIGO stage (OR=9.7), type (I/II) of tumor (OR=3.0) and VEGF‑R2 status (OR=0.2) were all found to be independent predictive factors in the cohort of patients (n=131). For patients with non‑serous tumors (n=78), the FIGO stage (OR=76), type (I/II) of tumor (OR=44), EGFR status (OR=0.05) and VEGF‑R2 status (OR=0.008) were all significant and independent predictive factors. On comparing the four subgroups, in terms of concomitant EGFR and VEGF‑R2 status, in a survival analysis, the subgroup of patients (n=21) with concomitant positive expression of EGFR and VEGF‑R2 had a 5‑year DFS rate of 100%. Therefore, the prognostic effect of EGFR and VEGF‑R2 for recurrent disease and survival rates was confirmed by the above findings. Certain results in the present study were not in line with results from previous studies on the prognostic effect of EGFR and VEGF‑R2. An increasing number of preclinical and clinical observations have shown that the process of angiogenesis remains to be fully elucidated. Therefore, one of the challenges for future ovarian cancer investigations is to identify which biomarkers may be used as predictive and prognostic markers.

Automated analysis of images for molecular quantification in immunohistochemistry

The quantification of the expression of different molecules is a key question in both basic and applied sciences. While protein quantification through molecular techniques leads to the loss of spatial information and resolution, immunohistochemistry is usually associated with time-consuming image analysis and human bias. In addition, the scarce automatic software analysis is often proprietary and expensive and relies on a fixed threshold binarization. Here we describe and share a set of macros ready for automated fluorescence analysis of large batches of fixed tissue samples using FIJI/ImageJ. The quantification of the molecules of interest are based on an automatic threshold analysis of immunofluorescence images to automatically identify the top brightest structures of each image. These macros measure several parameters commonly quantified in basic neuroscience research, such as neuropil density and fluorescence intensity of synaptic puncta, perisomatic innervation and col-localization of different molecules and analysis of the neurochemical phenotype of neuronal subpopulations. In addition, these same macro functions can be easily modified to improve similar analysis of fluorescent probes in human biopsies for diagnostic purposes based on the expression patterns of several molecules.

Collagen IV and laminin-1 expression in embryonic mouse lens using principal components analysis technique

Immunohistochemistry section staining is not always easy to interpret. Manual quantification of immunohistochemical staining is limited by the observer visual ability to detect changes in level staining. Hence, the quantification of immunostaining by means of digital image analysis allows us to measure accurately protein expression percentages in immunobiological stained tissues and ensures to overcome the visual limitations. We perform an experimental study to analyse the impact of folic acid (FA) deficiency into collagen IV and laminin-1 expression in the embryonic mouse lens. The study starts with microscope images of embryos mouse lens whose mothers fed a diet deficient in FA during 2 and 8 weeks. A principal component analysis (PCA) image processing is used to analyse these images coming from control and FA deficit groups. The method permits to define an index of over- or infraexpression of collagen IV and laminin-1 associated to different spatial organisation structures (PC processes). Additionally, it permits to determine in precise percentage the exact quantity of the overexpression or infraexpression and finally to comprehend molecular regionalisation and expression in both control and deficient groups. The results suggest that even with 2 weeks of deficit of FA the expression and distribution of both molecules is affected.

Potential skin involvement in ALS: revisiting Charcot's observation - a review of skin abnormalities in ALS

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting motor neurons of the brain and spinal cord, leading to progressive paralysis and death. Interestingly, many skin changes have been reported in ALS patients, but never as yet fully explained. These observations could be due to the common embryonic origin of the skin and neural tissue known as the ectodermal germ layer. Following the first observation in ALS patients' skin by Dr Charcot in the 19th century, in the absence of bedsores unlike other bedridden patients, other morphological and molecular changes have been observed. Thus, the skin could be of interest in the study of ALS and other neurodegenerative diseases. This review summarizes skin changes reported in the literature over the years and discusses about a novel in vitro ALS tissue-engineered skin model, derived from patients, for the study of ALS.

Quality Assessment of Prognostic Studies Using Cancer Stem Cell Markers in Oral Squamous Cell Carcinoma

Cancer stem cells (CSC) have been investigated as prognostic markers in oral squamous cell carcinoma (OSCC). However, an assessment of the reporting quality of these studies has not been performed yet. The aim of this study was to describe the reporting quality of prognostic studies involving CSCs and OSCC, focusing mainly on the immunohistochemical reproducibility. By means a systematic review, 34 articles were selected. Analyses of both general reporting quality and immunohistochemistry technique were performed by using checklists for multiple aspects related to study reproducibility. A total of 21 different CSC markers were cited in the selected studies, evaluated by means of a wide range of antibodies, most of them (40.3%) without clone description. Discrepancies in intracellular immunolabeling were noted for some markers. The mean global score for general quality assessment revealed limits in the quality of the articles. The main problems were related to lack of report on OSCC characteristics and treatment, sample size rationale, and sensitivity analysis or internal validation of the markers. Although there was a high frequency of studies having "good or very good" score for immunohistochemistry reproducibility, the frequency of articles with "poor or very poor" score for individual items was expressive, mainly for description of immunolabeling analysis (38.2% of the studies were poorly described). In conclusion, although there is a significant range of CSC markers with promising results for prognosis of OSCC, the inadequate reporting of important sections in the published studies, including immunohistochemistry technique, may limit the quality of the investigation.

The clinical and prognostic correlation of HRNPM and SLC1A5 in pathogenesis and prognosis in epithelial ovarian cancer

OBJECTIVES

To evaluate the prognostic effect of the Heterogeneous nuclear ribonucleoprotein type M (HNRPM) and Solute carrier 1A5 (SLC1A5) in FIGO-stages I-II epithelial ovarian cancer.

METHODS

A retrospective cohort study was designed to investigate the prognostic effect of HNRPM and SLC1A5, and the association with clinical-pathologic characteristics in 131 patients with FIGO-stages I-II epithelial ovarian cancer. Tissue microarrays were constructed and protein levels were assessed by immunohistochemistry (IHC).

RESULTS

Positive HRNPM status was associated with positive staining for PUMA (P = 0.04), concomitant PUMA and p21 staining (P = 0.005), and VEGF-R2 (P = 0.003). Positive SLC1A5 staining was associated with positive staining of p27 (P = 0.030), PUMA (P = 0.039), concomitant PUMA and p27 staining, and VEGF-R2 (P = 0.039). In non-serous tumors (n = 72), the SLC1A5 positivity was associated with recurrent disease (P = 0.01). In a multivariable logistic regression analysis FIGO-stage (OR = 12.4), tumor grade (OR = 5.1) and SLC1A5 positivity (OR = 0.1) were independent predictive factors for recurrent disease. Disease-free survival (DFS) in women with SLC1A5-positive non-serous tumors was 92% compared with of 66% in patients with SLC1A5-negative non-serous tumors (Log-rank = 15.343; P = 0.008). In Cox analysis with DFS as endpoint, FIGO-stage (HR = 4.5) and SLC1A5 status (HR = 0.3) were prognostic factors.

CONCLUSIONS

As the proteins HRNPM and SLC1A5 are associated with the cell cycle regulators p21 or p27, the apoptosis regulators PTEN and PUMA, and the VEGF-R2 it is concluded that both proteins have role in the pathogenesis of ovarian cancer. In patients with non-serous ovarian cancer SLC1A5 protects from recurrent disease, presumably by means of biological mechanisms that are unrelated to cytotoxic drug sensitivity.

Analysis of histological and immunohistochemical patterns of benign and malignant adrenocortical tumors by computerized morphometry

Diagnosis of benign and purely localized malignant adrenocortical lesions is still a complex issue. Moreover, histology-based diagnosis may suffer of a moment of subjectivity due to inter- and intra-individual variations. The aim of the present study was to assess, by computerized morphometry, the morphological features in benign and malignant adrenocortical neoplasms. Eleven adrenocortical adenomas (ACA) were compared with 18 adrenocortical cancers (ACC). All specimens were stained with H&E, cellular proliferation marker Ki-67 and reticulin. We generated a morphometric model based on the analysis of volume fractions occupied by Ki-67 positive and negative cells (nuclei and cytoplasm), vascular and inflammatory compartment; we also analyzed the surface fraction occupied by reticulin. We compared the quantitative data of Ki-67 obtained by morphometry with the quantification resulting from pathologist's visual reading. The volume fraction of Ki-67 positive cells in ACCs was higher than in ACAs. The volume fraction of nuclei in unit volume and the nuclear/cytoplasmic ratio in both Ki-67 negative cells and Ki-67 positive cells were prominent in ACCs. The surface fraction of reticulin was considerably lower in ACCs. Our computerized morphometric model is simple, reproducible and can be used by the pathologist in the histological workup of adrenocortical tumors to achieve precise and reader-independent quantification of several morphological characteristics of adrenocortical tumors.

Quantitative phase imaging for medical diagnosis

Optical microscopy is an indispensable diagnostic tool in modern healthcare. As a prime example, pathologists rely exclusively on light microscopy to investigate tissue morphology in order to make a diagnosis. While advances in light microscopy and contrast markers allow pathologists to visualize cells and tissues in unprecedented detail, the interpretation of these images remains largely subjective, leading to inter- and intra-observer discrepancy. Furthermore, conventional microscopy images capture qualitative information which makes it difficult to automate the process, reducing the throughput achievable in the diagnostic workflow. Quantitative Phase Imaging (QPI) techniques have been advanced in recent years to address these two challenges. By quantifying physical parameters of cells and tissues, these systems remove subjectivity from the disease diagnosis process and allow for easier automation to increase throughput. In addition to providing quantitative information, QPI systems are also label-free and can be easily assimilated into the current diagnostic workflow in the clinic. In this paper we review the advances made in disease diagnosis by QPI techniques. We focus on the areas of hematological diagnosis and cancer pathology, which are the areas where most significant advances have been made to date. [Image adapted from Y. Park, M. Diez-Silva, G. Popescu, G. Lykotrafitis, W. Choi, M. S. Feld, and S. Suresh, Proc. Natl. Acad. Sci. 105, 13730-13735 (2008).].

PATMA: parser of archival tissue microarray

Tissue microarrays are commonly used in modern pathology for cancer tissue evaluation, as it is a very potent technique. Tissue microarray slides are often scanned to perform computer-aided histopathological analysis of the tissue cores. For processing the image, splitting the whole virtual slide into images of individual cores is required. The only way to distinguish cores corresponding to specimens in the tissue microarray is through their arrangement. Unfortunately, distinguishing the correct order of cores is not a trivial task as they are not labelled directly on the slide. The main aim of this study was to create a procedure capable of automatically finding and extracting cores from archival images of the tissue microarrays. This software supports the work of scientists who want to perform further image processing on single cores. The proposed method is an efficient and fast procedure, working in fully automatic or semi-automatic mode. A total of 89% of punches were correctly extracted with automatic selection. With an addition of manual correction, it is possible to fully prepare the whole slide image for extraction in 2 min per tissue microarray. The proposed technique requires minimum skill and time to parse big array of cores from tissue microarray whole slide image into individual core images.

Fatal pyogranulomatous myocarditis in 10 Boxer puppies

Over a period of 5 years, 10 pure-bred Boxer puppies, 9-16 weeks old, were presented with a history of sudden death and were diagnosed with pyogranulomatous myocarditis. The myocarditis was characterized by a mixed infiltrate composed predominantly of neutrophils and macrophages. In our retrospective study, original case records and archived materials were examined. All dogs were positive for Borrelia burgdorferi on immunohistochemistry (IHC). There was no evidence of infectious agents in formalin-fixed, paraffin-embedded (FFPE) heart tissue sections stained with hematoxylin and eosin, Ziehl-Neelsen, Gram, Grocott methenamine silver, Warthin-Starry, Von Kossa, and Steiner-Chapman stains. IHC for Chlamydia sp., Toxoplasma gondii, Neospora caninum, West Nile virus, and canine parvovirus also yielded a negative result in all dogs. Polymerase chain reaction testing for vector-borne pathogens on heart tissue from 9 of the dogs (1 frozen and 8 FFPE samples) yielded positive results for 1 dog with B. burgdorferi as well as Anaplasma phagocytophilum in another dog. Subsequently, 2 additional cases were found in a French Bulldog and a French Bulldog-Beagle mix that had identical morphology, test results, age, and seasonality to these 10 Boxer dogs. The similarities in the seasonality, signalment of the affected dogs, and the gross and microscopic lesions suggest a common etiology. Positive IHC and morphologic similarities to human Lyme carditis indicate that B. burgdorferi is likely the agent involved. An additional consideration for these cases is the possibility of a breed-specific autoimmune myocarditis or potential predisposition for cardiopathogenic agents in young Boxers.

Multiplex Gene Expression Profiling of 16 Target Genes in Neoplastic and Non-Neoplastic Canine Mammary Tissues Using Branched-DNA Assay

Mammary gland tumors are one of the most common neoplasms in female dogs, and certain breeds are prone to develop the disease. The use of biomarkers in canines is still restricted to research purposes. Therefore, the necessity to analyze gene profiles in different mammary entities in large sample sets is evident in order to evaluate the strength of potential markers serving as future prognostic factors. The aim of the present study was to analyze the gene expression of 16 target genes (BRCA1, BRCA2, FOXO3, GATA4, HER2, HMGA1, HMGA2, HMGB1, MAPK1, MAPK3, MCL1, MYC, PFDN5, PIK3CA, PTEN, and TP53) known to be involved in human and canine mammary neoplasm development. Expression was analyzed in 111 fresh frozen (FF) and in 170 formalin-fixed, paraffin-embedded (FFPE) specimens of neoplastic and non-neoplastic canine mammary tissues using a multiplexed branched-DNA (b-DNA) assay. TP53, FOXO3, PTEN, and PFDN5 expression revealed consistent results with significant low expression in malignant tumors. The possibility of utilizing them as predictive factors as well as for assisting in the choice of an adequate gene therapy may help in the development of new and improved approaches in canine mammary tumors.

Subcellular Localization of Immunohistochemical Signals

In the literature, sufficient attention has not been paid to the precise subcellular localization of immunohistochemical signals, the knowledge of which is essential for proper interpretation of immunostains and distinction of genuine staining from biotin-associated or other nonspecific stainings. The subcellular localization of the signals can in fact be easily deduced from the known biologic or ultrastructural characteristics of the antigens. Extracellular antigens obviously are located in the extracellular compartment. Cellular antigens fall into 3 major groups: membranous, nuclear, and cytoplasmic. Membranous antigens include cell adhesion molecules (such as E-cadherin, N-CAM), cell surface/transmembrane receptors and proteins (such as tyrosine kinase receptors, most leukocyte antigens, CD10, CEA), and molecules linking surface molecules to cytoskeleton (such as β-catenin, dystrophin). Nuclear antigens include cell cycle-associated proteins (such as cyclins, p16, Ki-67), nuclear enzymes (such as TdT), transcription factors (such as TTF-1, CDX-2, myogenin, PAX-5), tumor suppressor gene products (such as p53, p63, WT1, Rb), steroid hormone receptors (such as ER, PR), calcium-binding proteins (such as S-100 protein, calretinin), and some viral proteins (such as CMV, herpes). Cytoplasmic antigens can take up a granular pattern due to localization in organelles, granules, or secretory vesicles (such as chromogranin, hormones, lysozyme, HMB-45), fibrillary pattern attributable to the filamentous nature of the molecules (intermediate filaments and microfilaments), or diffuse or patchy pattern due to localization in the cytosol or large vesicles (such as myoglobin, albumin, thyroglobulin). Aberrant localization of the molecules, when present, can provide important insight into disease processes and aid in their diagnosis, such as loss of membranous E-cadherin expression in lobular breast carcinoma, aberrant nuclear localization of β-catenin in colorectal adenocarcinoma, pattern of ALK staining in anaplastic large cell lymphoma correlating with the different types of chromosomal translocations, presence of additional cytoplasmic CD10 staining in the enterocytes indicative of microvillous inclusion disease, and “reversed” staining for EMA in micropapillary mammary carcinoma.

The relationship of the angiogenesis regulators VEGF-A, VEGF-R1 and VEGF-R2 to p53 status and prognostic factors in epithelial ovarian carcinoma in FIGO-stages I-II

The aim of this study was to evaluate prognostic effect of the angiogenesis regulators VEGF-R1, VEGF-R2 and VEGF-A for recurrent disease and disease-free survival (DFS), and their relation to the apoptosis regulator p53, in 131 patients with FIGO-stages I-II with epithelial ovarian cancer. For the detection of positivity of the markers the techniques of tissue microarrays and immunohistochemistry (IHC) were used. In tumors the frequency of positive staining for VEGF-R1 was 19%, for VEGF-R2 and VEGF-A, it was 77 and 70%, respectively. Positivity for p53 was detected in 25% of tumors. The total number of recurrences in the complete series was 34 out of 131 (26%) and 5-year disease-free survival (DFS) was 68%. Positive staining for VEGF-A (P=0.030), VEGF-R2 (P=0.011) and p53 (P=0.015) was found more frequently in type II tumors than in type I tumors. Patients with VEGF-R1 negative tumors had worse (P=0.021) DFS compared to patients with VEGF-R1 positive tumors. In two multivariate Cox analyzes with DFS as endpoint, FIGO-stage (HR=3.8), VEGF-R2 status (HR=0.4) and p53 status (HR=2.3), all were significant and independent prognostic factors. When the variables VEGF-R2 and p53 were replaced with the new variable VEGF-R2+p53-/other three combinations in one group, it was found that patients from that subgroup had 86% reduced risk of dying in disease (HR=0.24). Findings above, confirmed relationship between VEGF-R2 and VEGF-A and p53, respectively, with regard to recurrent disease and survival. Some findings from the present study are different from results from previous studies on the regulation of angiogenesis. Despite many trials with anti-angiogenic agents in the front line of ovarian cancer have shown to be positive for progression-free survival, no one has demonstrated an impact on overall survival. Therefore, one of the greatest challenges in ovarian cancer research, is to discover predictive and prognostic biomarkers.

Spatially Resolved Quantification of Chromatin Condensation through Differential Local Rheology in Cell Nuclei Fluorescence Lifetime Imaging

The linear sequence of DNA encodes access to the complete set of proteins that carry out cellular functions. Yet, much of the functionality appropriate for each cell is nested within layers of dynamic regulation and organization, including a hierarchy of chromatin structural states and spatial arrangement within the nucleus. There remain limitations in our understanding of gene expression within the context of nuclear organization from an inability to characterize hierarchical chromatin organization in situ. Here we demonstrate the use of fluorescence lifetime imaging microscopy (FLIM) to quantify and spatially resolve chromatin condensation state using cell-permeable, DNA-binding dyes (Hoechst 33342 and PicoGreen). Through in vitro and in situ experiments we demonstrate the sensitivity of fluorescence lifetime to condensation state through the mechanical effects that accompany the structural changes and are reflected through altered viscosity. The establishment of FLIM for resolving and quantifying chromatin condensation state opens the door for single-measurement mechanical studies of the nucleus and for characterizing the role of genome structure and organization in nuclear processes that accompany physiological and pathological changes.

Differences in Clinical and Biological Features Between Type I and Type II Tumors in FIGO Stages I-II Epithelial Ovarian Carcinoma

OBJECTIVE

The objective of this study was to compare immunohistochemical profile for the apoptosis regulators p53, C-MYC, bax, PUMA, and PTEN and the cell cycle regulatory proteins p21 and p27, as well as clinical factors between types I and II tumors.

METHODS

In total, 131 patients in FIGO (International Federation of Gynecology and Obstetrics) stages I-II were divided into 2 groups of patients after type I tumors (n = 79) and type II tumors (n = 52). Differences in the immunohistochemical profile for the cell cycle-related proteins, detected by tissue microarrays and immune-histochemistry, were compared. For statistical tests, the Pearson χ test and the logistic regression model were used. All tests were 2-sided, and the level of statistical significance was P ≤ 0.05.

RESULTS

In multivariate logistic regression analysis with recurrent disease as endpoint, FIGO stage (odds ratio [OR], 4.7), type I/II tumors (OR, 3.8), body mass index (BMI) (OR, 3.5), and p53 status (OR, 4.2) all were found to be independent predictive factors. In 2 different multivariate logistic regression analyses with type I/II tumors as endpoint, both p53p21 (OR, 2.9) and p27 status (OR, 3.0) were associated with type II tumors. Differently, C-MYC status (OR, 0.4) was associated with type I tumors. Furthermore, age (OR, 1.04), BMI (OR, 0.4), and recurrent disease (OR, 4.3) all were associated to type II tumors. In survival analysis, there was a trend (P = 0.054) toward better disease-free survival for patients with type I tumors.

CONCLUSIONS

Concomitant positivity for p53 and negativity for p21, positivity for p27, and negativity for C-MYC in an epithelial ovarian tumor might strengthen the diagnostic option of type II tumor ovarian carcinoma. Patients with type II tumors were older, had lower BMI, and had more often recurrent disease than patients with type I tumors.

Comparison of the manual, semiautomatic, and automatic selection and leveling of hot spots in whole slide images for Ki-67 quantification in meningiomas

Background. This paper presents the study concerning hot-spot selection in the assessment of whole slide images of tissue sections collected from meningioma patients. The samples were immunohistochemically stained to determine the Ki-67/MIB-1 proliferation index used for prognosis and treatment planning. Objective. The observer performance was examined by comparing results of the proposed method of automatic hot-spot selection in whole slide images, results of traditional scoring under a microscope, and results of a pathologist's manual hot-spot selection. Methods. The results of scoring the Ki-67 index using optical scoring under a microscope, software for Ki-67 index quantification based on hot spots selected by two pathologists (resp., once and three times), and the same software but on hot spots selected by proposed automatic methods were compared using Kendall's tau-b statistics. Results. Results show intra- and interobserver agreement. The agreement between Ki-67 scoring with manual and automatic hot-spot selection is high, while agreement between Ki-67 index scoring results in whole slide images and traditional microscopic examination is lower. Conclusions. The agreement observed for the three scoring methods shows that automation of area selection is an effective tool in supporting physicians and in increasing the reliability of Ki-67 scoring in meningioma.

Lack of effects of HER-2/neu on prognosis in colorectal cancer: a meta-analysis

BACKGROUND

The prognostic value of human epidermal growth factor receptor-2 (HER-2/neu) for survival of patients with colorectal cancer (CRC) is still ambiguous. We therefore performed a meta-analysis to evaluate its prognostic significance.

MATERIALS AND METHODS

We searched the MEDLINE and EMBASE databases for published literature investigating associations between HER-2/neu status and overall survival of patients with CRC. A meta-analysis was performed using a DerSimonian-Laird model and publication bias was investigated by Begg's and Egger's tests. Subgroup analysis was also conducted according to the study design type, study quality score, cut-off value for HER-2/neu overexpression, publication region, patient number and publication year.

RESULTS

A total of 17 eligible studies involving 2,347 patients were identified for this meta-analysis. The combined hazard ratio (HR) was 1.31 (95% confidence interval (CI): 0.96-1.79), suggesting that HER-2/neu overexpression was not significantly associated with overall survival of patients with CRC. However, subgroup analysis revealed that HER-2/neu overexpression had an unfavorable impact on survival when the analysis was restricted to subgroups of study quality score ≤ 5 (HR=1.56, 95%CI: 1.17-2.10), Asian patients (HR=1.74, 95%CI: 1.22-2.49), patient number ≤ 106 (HR=1.57, 95%CI: 1.01-2.44), publication year before 2003 (HR=1.59, 95%CI: 1.02-2.49), and prospectively designed study (HR=3.62, 95%CI: 1.42-9.24). The effect disappeared in subgroups of study quality scores > 5 (HR=0.69, 95%CI: 0.33-1.44), non Asian patients (HR=1.14, 95%CI: 0.77-1.70), patients' number > 106 (HR=1.07, 95%CI: 0.67-1.72), publication year after 2003 (HR=1.13, 95%CI: 0.76-1.69), and retrospectively designed study (HR=1.22, 95%CI: 0.89-1.67).

CONCLUSIONS

Our meta-analysis suggests that HER-2/neu overexpression might not be a significantly prognostic indicator for patients with CRC. Further studies are required to confirm these results.

Capillary nano-immunoassays: advancing quantitative proteomics analysis, biomarker assessment, and molecular diagnostics

There is an emerging demand for the use of molecular profiling to facilitate biomarker identification and development, and to stratify patients for more efficient treatment decisions with reduced adverse effects. In the past decade, great strides have been made to advance genomic, transcriptomic and proteomic approaches to address these demands. While there has been much progress with these large scale approaches, profiling at the protein level still faces challenges due to limitations in clinical sample size, poor reproducibility, unreliable quantitation, and lack of assay robustness. A novel automated capillary nano-immunoassay (CNIA) technology has been developed. This technology offers precise and accurate measurement of proteins and their post-translational modifications using either charge-based or size-based separation formats. The system not only uses ultralow nanogram levels of protein but also allows multi-analyte analysis using a parallel single-analyte format for increased sensitivity and specificity. The high sensitivity and excellent reproducibility of this technology make it particularly powerful for analysis of clinical samples. Furthermore, the system can distinguish and detect specific protein post-translational modifications that conventional Western blot and other immunoassays cannot easily capture. This review will summarize and evaluate the latest progress to optimize the CNIA system for comprehensive, quantitative protein and signaling event characterization. It will also discuss how the technology has been successfully applied in both discovery research and clinical studies, for signaling pathway dissection, proteomic biomarker assessment, targeted treatment evaluation and quantitative proteomic analysis. Lastly, a comparison of this novel system with other conventional immuno-assay platforms is performed.

Determination of Tumor Heterogeneity in Colorectal Cancers Using Heterogeneity Tissue Microarrays

Cancer is often heterogeneous both on a morphological and on a genetic level. Though resected tumors are often large, molecular tumor analysis is usually restricted to one tissue block. In this project we introduce a new tool for a high-throughput heterogeneity analysis of colorectal cancer. A heterogeneity tissue microarray (TMA) was manufactured from tissues of 340 patients with colorectal cancer. For this purpose 8 different tissue spots were taken from as many different cancer blocks per patient as possible (at least 4 different blocks). Additional tissue samples from 1 to 4 corresponding lymph node metastases were added from 134 patients. The system was then validated by analysing one parameter each known for minimal (p53) or substantial (HER2) heterogeneity in colorectal cancer. P53 alterations as detected by immunohistochemistry were seen in 174 (51.3 %) of 339 analyzable primary tumors of which 23 (13.2 % of positive cases) showed a heterogeneous distribution pattern. HER2 overexpression was seen in 18 (5.4 %) of 336 evaluable tumors. HER2 amplification occurred in 6 (33.3 %) of the 18 cases with HER2 overexpression. Genomic heterogeneity was more prevalent for HER2 alterations than for p53 alterations. For immunohistochemical expression analysis, 16 of 18 positive cases were heterogeneous (88.9 %) and for amplification 3 of 6 cases (50 %) were heterogeneous. Large section validation revealed, however a considerable fraction of heterogeneous cases were due to technical artifacts. In summary, our data suggest, that heterogeneity TMAs are a powerful tool to rapidly screen for molecular heterogeneity in colorectal cancer.

Study of C-MYC amplification and expression in Iranian gastric cancer samples using CISH and IHC methods

Background:

Gastric cancer is the fourth most frequent malignancy and the second cause of cancer-related mortality worldwide. It has been suggested that in gastric carcinogenesis, the C-MYC gene has an important function. The objective of this study is to establish the preference of Chromogenic in situ hybridization (CISH) and Immunohistochemistry (IHC) in the diagnosis and prognosis of gastric cancer.

Materials and Methods:

Samples comprised of 50 randomly selected patients of whom 40 were male and 10 female. To evaluate the MYC copy number and its protein expression, CISH and IHC analyses were performed for 50 gastric adenocarcinomas, in Iran.

Results:

The location of the tumor in 64% of the patients was the fundus, and in 72% of patients, the tumors were of a diffuse type; 22 samples showed no amplification, and 28 samples were with amplification. MYC immunoreactivity was observed in 13 samples. Twelve samples showed both MYC amplification and MYC immunoreactivity. In addition, among the 28 CISH+ samples, 12 samples had positive signals for IHC and 16 samples had negative signals for IHC. A majority of the IHC-negative patients had no amplification, but only one patient with IHC positive had no amplification.

Conclusion:

Our conclusion was that for the management and treatment of gastric cancer, and for special attention of clinicians, for prognosis and tumor progression, the CISH was a better and more feasible test than IHC, in regard to the sensitivity and specificity.

Immunohistochemical distribution of leptin in kidney tissues of melatonin treated diabetic rats

We examined using immunohistochemistry the distribution of leptin in kidney tissues of melatonin treated, streptozotocin (STZ) diabetic rats. The animals were divided into five groups: control, sham, melatonin-treated, diabetic and melatonin-treated diabetic. Kidney sections were prepared and stained with hematoxylin and eosin, and Crossman's triple staining for histological examination. The immunohistochemical localization of leptin in the kidney tissue was determined using the streptavidin-biotin-peroxidase method. We determined that on days 7 and 14, the leptin immunoreactivity of the diabetic and melatonin-treated diabetic groups was weaker than for the other groups. Weak immunoreactivity was found in the proximal and distal tubules of the kidney in the diabetic and melatonin-treated diabetic groups on days 7 and 14, and strong immunoreactivity was found in the control, sham and melatonin groups. Melatonin application had no significant effect on leptin production in the kidney tissues of diabetic rats.

Quantitation of microRNA-92a in colorectal adenocarcinoma and its precancerous lesions: Co-utilization of in situ hybridization and spectral imaging

The expression level of microRNA (miR)-92a has been proven to increase during the development of colorectal adenocarcinoma (CA) and has been verified at the cellular, plasma and fecal levels by various quantitative methods. However, a method to quantitate the expression level using tissue sections has not been established. To do this, in situ hybridization (ISH) and multispectral imaging microscopy (MSI) were introduced to quantitate miR-92a expression on the microscopic level. ISH of miR-92a was first performed on 34 tissue samples of CA and adenomas with high-grade and low-grade intraepithelial neoplasms, while 31 paralesional normal tissue samples were defined as the control. Subsequently, a MSI technique was applied to quantitate the hybridization signal in terms of optical density (OD) at the visible wavelength. A t-test with unequal variance was used to examine the statistical significance between the groups. Despite all 34 tissue sections demonstrating at least partial positivity of miR-92a expression following ISH, visual grading was inconclusive. As such, the signal of ISH was transformed in terms of OD and further analyzed by employing the MSI system. A statistically significant difference was observed between the expression levels of miR-92a in CA and the paralesional normal controls. By contrast, a poor correlation was revealed between visual and spectral grading. The co-utilization of ISH and MSI generated a legible observation in the expression level of miR-92a, revealing the dynamic change in miR-92a expression in the progression of the disease and providing important information for further functional investigation.

Standardization of Diagnostic Immunohistochemistry: Literature Review and Geisinger Experience

Context

Immunohistochemistry has become an indispensable ancillary technique in anatomic pathology laboratories. Standardization of every step in preanalytic, analytic, and postanalytic phases is crucial to achieve reproducible and reliable immunohistochemistry test results.

Objective

To standardize immunohistochemistry tests from preanalytic, analytic, to postanalytic phases.

Data Sources

Literature review and Geisinger (Geisinger Medical Center, Danville, Pennsylvania) experience.

Conclusions

This review article delineates some critical points in preanalytic, analytic, and postanalytic phases; reiterates some important questions, which may or may not have a consensus at this time; and updates the newly proposed guidelines on antibody validation from the College of American Pathologists Pathology and Laboratory Quality Center. Additionally, the article intends to share Geisinger's experience with (1) testing/optimizing a new antibody and troubleshooting; (2) interpreting and reporting immunohistochemistry assay results; (3) improving and implementing a total immunohistochemistry quality management program; and (4) developing best practices in immunohistochemistry.

Different approaches for interpretation and reporting of immunohistochemistry analysis results in the bone tissue - a review

BACKGROUND

Immunohistochemistry (IHC) is a well-established, widely accepted method in both clinical and experimental parts of medical science. It allows receiving valuable information about any process in any tissue, and especially in bone. Each year the amount of data, received by IHC, grows in geometric progression. But the lack of standardization, especially on the post-analytical stage (interpreting and reporting of results), makes the comparison of the results of different studies impossible.

METHODS

Comprehensive PubMED literature search with a combination of search words "immunohistochemistry" and "scoring system" was performed and 773 articles describing IHC results were identified. After further manual analysis 120 articles were selected for detailed evaluation of used approaches.

RESULTS

Six major approaches to the interpretation and presentation of IHC analysis results were identified, analyzed and described.

CONCLUSIONS

The overview of the existing approaches in evaluation and interpretation of IHC data, which are provided in the article, can be used in bone tissue research and for either better understanding of existing scoring systems or developing a new one. Standard multiparametric, semiquantitative IHC scoring systems should simplify and clarify the process of interpretation and reporting of received data.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_221.

Significance of human epidermal growth factor receptor 2 expression in colorectal cancer

The aim of the present study was to evaluate the protein expression level of human epidermal growth factor receptor 2 (HER-2) using immunohistochemistry (IHC), and assess the association with clinicopathological parameters and the prognosis of patients with colorectal cancer (CRC). In addition, the current study observed the consistency between the levels of HER-2 protein expression determined by IHC and HER-2 gene amplification determined by fluorescence in situ hybridization (FISH) in the CRC samples. Overexpression of HER-2 and gene amplification were examined with semiquantitative standardized IHC in 878 formalin-fixed paraffin-embedded CRC samples, while 102 of these cases were analyzed with FISH. A total of 102 cases (11.6%), out of the 878 cases, were determined by IHC to overexpress HER-2. Of these, 25 cases were strongly positive (IHC3+), while 77 cases revealed moderate staining (IHC2+). HER-2 overexpression was more frequent in early-stage cases compared with advanced-stage cases of CRC (P<0.001). However, there was no association observed between HER-2 overexpression and clinicopathological parameters. FISH analysis revealed that 64% (16/25) of the IHC3+ cases had HER-2 gene amplification. By contrast, only 6.5% (5/77) of the IHC2+ cases, and none of the 20 randomly selected IHC0 or 1+ cases, demonstrated HER-2 gene amplification. Furthermore, no associations were observed between HER-2 overexpression or gene amplification with the survival time. Thus, the present study observed that HER-2 overexpression does not correlate with other clinicopathological data or the survival rate, with the exception of clinical stages. However, IHC3+ and 2+ cases should be further analyzed by FISH to assess the status of the HER-2 gene in CRC. Patients with HER-2 gene amplification may constitute as potential candidates for targeted therapy with trastuzumab.