Immunohistochemical Quantification Research Articles

ITGB3 is a Novel Prognostic Biomarker and Correlates with Aberrant Methylation and Tumor Immunity in Clear Cell Renal Cell Carcinoma.

Current evidence highlights clear cell renal carcinoma (ccRCC) as the most prevalent form of kidney cancer despite ongoing challenges in treating advanced-stage disease. Integrin subunit beta 3 (ITGB3) has recently emerged as a critical player in tumorigenesis, prompting our investigation into its role in ccRCC. This study aimed to elucidate the mechanisms responsible for ITGB3 downregulation and evaluate its clinical significance, particularly regarding its impact on the immune landscape within ccRCC. We first conducted analyses utilizing data from both TCGA and GEO datasets to explore ITGB3 expression in ccRCC tissues. Subsequently, we evaluated the association between ITGB3 expression levels and patient prognosis and pathological staging. Pathway and functional enrichment analyses were performed to assess correlations between ITGB3 and immune and methylation-related pathways. Additionally, we examined the relationship between ITGB3 transcriptional expression and DNA hypermethylation. A prognostic risk model was developed using LASSO-based analysis on selected ITGB3-associated DNA methylation probes. Immunohistochemistry (IHC) analysis, alongside TIMER and ssGSEA results, was utilized to investigate ITGB3 expression and its association with immune cell infiltration. Our analyses revealed significant downregulation of ITGB3 mRNA expression in ccRCC tissues compared to other members of the ITGB family, consistent across TCGA and GEO datasets. Higher ITGB3 expression correlated with improved prognosis and lower pathological stage in ccRCC patients. Pathway and functional enrichment analyses demonstrated positive correlations between ITGB3 and immune and methylation-related pathways, while ITGB3 transcriptional expression showed a negative correlation with DNA hypermethylation. The established prognostic risk model identified a high-risk group with poorer survival probabilities than the low-risk group. Immunohistochemical quantification revealed a positive correlation between CD4+ and CD8+ immune cell infiltration and ITGB3 expression. Overall, our study provides compelling evidence supporting the significant role of ITGB3 in ccRCC immunity. The downregulation of ITGB3, coupled with its association with better prognosis and immune activation, suggests its potential as a therapeutic target and prognostic marker for this patient population.

Low Dose of Nickel and Benzo [a] Anthracene in Rat-Diet, Induce Apoptosis, Fibrosis, and Initiate Carcinogenesis in Liver via NF-Ƙβ Pathway.

Environmental contaminants such as polycyclic aromatic hydrocarbon (PAH) and heavy metals are major contaminants of food such as fish thus serving as source of exposure to human. This study was designed to evaluate the carcinogenic risk and other risks associated with long-term consumption of environmentally relevant dose of nickel and benzo [a] anthracene in rats. Thirty-six (36) male rats weighing between 80 and 100 g were assigned into 6 groups of 6 animals each; normal, nickel-, and benzo [a] anthracene-exposed groups for 12 and 24 weeks, respectively. Micronucleus and comet analyses were done in the blood, liver, and bone marrow. Liver function, redox, and inflammatory markers (AST, ALT, GGT, SOD, GSH, MDA, protein carbonyl, protein thiol, total protein, IL-10, 1L-1β, TNF-α, TGF-β NF-Ƙβ, and 8-oxodeoxyguansine) were analysed by standard methods. Immuno-histochemical quantification of Bax, Bcl2, and Erk 1/2 as well as mRNA expression of cyclin D1 was done in liver. From the results, weight gain was observed in varying degrees throughout the exposure period. The polychromatic erythrocytes/normochromatic erythrocytes ratio >0.2 indicates no cytotoxic effects on the bone marrow. Percentage-MnPCE in blood significantly (p<0.05) increased throughout exposure duration. Percentage tail DNA in blood was significantly (<0.05) increased at weeks 20 and 24 in the exposed groups and in liver at weeks 12 (16.22±0.47) and 24 (17.00±0.36) of nickel-exposed rats. The aspartate amino transferase (AST):alanine amino transferase (ALT) ratio indicated fatty liver disease in the benzo [a] anthracene (0.90) and acute liver injury in the nickel (>10 times greater than the upper limits of the reference group) exposed groupsduring the first 12 weeks. Observation from the histological and cytological data of the liver revealed the presence of inflammation, fibrosis, and high nuclear/cytoplasmic ratio, respectively, in the nickel and benzo [a] anthracene groups. Only benzo [a] anthracene induced liver oxidative stress with significant (p<0.05) decrease in SOD (0.64±0.02) activity and increase in protein carbonyl (7.60±0.80×10-5) and MDA (57.10±6.64) concentration after 24 weeks. Benzo [a] anthracene up-regulated the cyclin D1 expression and significantly (p<0.05) increased the levels of the cytokines. Nickel and benzo [a] anthracene significantly (p<0.05) increased the Bax (183.45±6.50 and 199.76±10.04) and Erk 1/2 (108.25±6.41 and 136.74±4.22) levels when compared with the control (37.43±22.22 and 60.37±17.86), respectively. Overall result showed that the toxic effects of nickel and benzo [a] anthracene might involve fibrosis, cirrhosis, apoptosis, and inflammation of the liver. As clearly demonstrated in this study, benzo [a] anthracene after the 24 weeks of exposure stimulates carcinogenic process by suppressing the liver antioxidant capacity, altering apoptotic, cell proliferation, and differentiation pathways.

Neuroprotection of Cholinergic Neurons with a Tau Aggregation Inhibitor and Rivastigmine in an Alzheimer's-like Tauopathy Mouse Model.

Basal forebrain cholinergic dysfunction, most likely linked with tau protein aggregation, is a characteristic feature of Alzheimer's disease (AD). Recent evidence suggests that tau protein is a putative target for the treatment of dementia, and the tau aggregation inhibitor, hydromethylthionine mesylate (HMTM), has emerged as a potential disease-modifying treatment. However, its efficacy was diminished in patients already receiving approved acetylcholinesterase inhibitors. In this study, we ask whether this negative interaction can also be mimicked in experimental tau models of AD and whether the underlying mechanism can be understood. From a previous age profiling study, 6-month-old line 1 (L1) tau transgenic mice were characterized by a severe reduction in several cholinergic markers. We therefore assessed whether long-term pre-exposure with the acetylcholinesterase inhibitor rivastigmine alone and in conjunction with the tau aggregation inhibitor HMTM can reverse cholinergic deficits in L1. Rivastigmine and HMTM, and combinations of the two compounds were administered orally for 11 weeks to both L1 and wild-type mice. The brains were sectioned with a focus on the basal forebrain, motor cortex and hippocampus. Immunohistochemical staining and quantification of choline acetyltransferase (ChAT), tyrosine kinase A (TrkA)-positive neurons and relative optical intensity (ROI) for vesicular acetylcholine transporter (VAChT), and acetylcholinesterase (AChE) reactivity confirmed reversal of the diminished cholinergic phenotype of interneurons (nucleus accumbens, striatum) and projection neurons (medial septum, nucleus basalis magnocellularis) by HMTM, to a greater extent than by rivastigmine alone in L1 mice. Combined administration did not yield additivity but, in most proxies, led to antagonistic effects in which rivastigmine decreased the benefits shown with HMTM alone. Local markers (VAChT and AChE) in target structures of the basal forebrain, motor cortex and hippocampal CA3 seemed to be normalized by HMTM, but not by rivastigmine or the combination of both drugs. HMTM, which was developed as a tau aggregation inhibitor, strongly decreased the tau load in L1 mice, however, not in combination with rivastigmine. Taken together, these data confirm a cholinergic phenotype in L1 tau transgenic mice that resembles the deficits observed in AD patients. This phenotype is reversible by HMTM, but at the same time appears to be subject to a homeostatic regulation induced by chronic pre-treatment with an acetylcholinesterase inhibitor, which interferes with the efficacy of HMTM. The strongest phenotypic reversal coincided with a normalization of the tau load in the cortex and hippocampus of L1, suggesting that tau accumulation underpins the loss of cholinergic markers in the basal forebrain and its projection targets.

Higher densities of T-lymphocytes in the subsynovial connective tissue of people with carpal tunnel syndrome.

Symptoms in people with carpal tunnel syndrome (CTS) are traditionally attributed to neural tissue, but recent studies suggest that the subsynovial connective tissue (SSCT) may also play a role in CTS. The SSCT undergoes fibrotic thickening which is generally described as "non-inflammatory" based on basic histology. This study uses immunohistochemistry to determine the presence of macrophages and T-cells within SSCT and their relationship with symptoms in people with CTS. SSCT was collected from twenty people with CTS and eight controls undergoing wrist fracture surgery. Immunohistochemical quantification of CD3+ T-cells and CD68+ macrophage densities as well as CD4+/CD8+ T-cell subpopulations were compared between groups using independent t-tests. Spearman correlations were used to identify associations between immune cell densities and CTS symptom scores. The density of CD3+ T-cells was significantly higher in SSCT of people with CTS compared to controls (CTS mean 26.7 (SD 13.7); controls 6.78 (6.3), p = 0.0005) while the density of CD68+ macrophages was lower (CTS mean 9.5 (SD 6.0); controls 17.7 (8.2), p = 0.0058). Neither CD68+ nor CD3+ cell densities correlated with symptom scores. In contrast to previous assumptions, our data show that the SSCT in the carpal tunnel in both people with CTS and controls is not devoid of immune cells. Whereas the higher density of CD68+ macrophages in control participants may be associated with their early recruitment after acute fracture, CD3+ cells within the SSCT may play a role in chronic CTS.

Investigation of Gastrointestinal Toxicities Associated with Concurrent Abdominal Radiation Therapy and the Tyrosine Kinase Inhibitor Sunitinib in a Mouse Model.

Tyrosine kinase inhibitors (TKIs) may be combined with radiation therapy (RT) to enhance tumor control; however, increased incidences of gastrointestinal (GI) toxicity have been reported with this combination. We hypothesize that toxicity is due to compromised intestinal healing caused by inhibition of vascular repair and proliferation pathways. This study explores underlying tissue toxicity associated with abdominal RT and concurrent sunitinib in a mouse model. Four groups of CD-1 mice were treated with 12 Gy abdominal RT, oral sunitinib, abdominal RT + sunitinib, or sham treatment. Mice received oral sunitinib or the vehicle via gavage for 14 days. On day 7, mice were irradiated with 12 Gy abdominal RT or sham treated. Mice were euthanized on day 14 and intestinal tract was harvested for semiquantitative histopathologic evaluation and immunohistochemical quantification of proliferation (Ki67) and vascular density (CD31). Non-irradiated groups had stable weights while abdominal irradiation resulted in weight loss, with mice receiving RT + SUN having greater weight loss than mice receiving RT alone. Semiquantitative analysis showed significant increases in inflammation in irradiated groups. The difference in the density of CD31+ cells was significantly increased in RT alone compared to SUN alone. Ki67+ density was not significant. In summary, we identify a lack of angiogenic response in irradiated GI tissues when abdominal RT is combined with a TKI, which may correlate with clinical toxicities seen in canine and human patients receiving combined treatment.

Novel quantitative immunohistochemistry method using histone H3, family 3B as the internal reference standard for measuring human epidermal growth factor receptor 2 expression in breast cancer.

Immunohistochemistry (IHC) is an essential technique in surgical and clinical pathology for detecting diagnostic, prognostic, and predictive biomarkers for personalized cancer therapy. However, the lack of standardization and reference controls results in poor reproducibility, and a reliable tool for IHC quantification is urgently required. The objective of this study was to describe a novel approach in which H3F3B (histone H3, family 3B) can be used as an internal reference standard to quantify protein expression levels using IHC. The authors enrolled 89 patients who had human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). They used a novel IHC-based assay to measure protein expression using H3F3B as the internal reference standard. H3F3B was uniformly expressed at the protein level in all tumor regions in cancer tissues. HER2 expression levels were measured with the H-score using HALO software. Kaplan-Meier analysis indicated that, among patients who had HER2-positive BC in The Cancer Genome Atlas data set and the authors' data set, the subgroup with low HER2 expression had a significantly better prognosis than the subgroup with high HER2 expression. Furthermore, the authors observed that HER2 expression levels were precisely evaluated using the proposed method, which can classify patients who are at higher risk of HER2-positive BC to receive trastuzumab-based adjuvant therapy. Dual-color IHC with H3F3B is an excellent tool for internal and external quality control of HER2 expression assays. The proposed IHC-based quantification method accurately assesses HER2 expression levels and provides insights for predicting clinical prognosis in patients with HER2-positive BC who receive trastuzumab-based adjuvant therapy.

High microvessel and lymphatic vessel density predict poor prognosis in patients with esophageal squamous cell carcinoma.

Microangiogenesis and lymphangiogenesis are essential for tumor growth in the tumor microenvironment, contributing to tumor invasion and metastasis. Limited literature exists on these processes in esophageal squamous cell carcinoma (ESCC). Therefore, the purpose of this study is to explore the impacts of microangiogenesis and lymphangiogenesis on the occurrence, progression, and prognosis assessment of ESCC. Surgical specimens and paraffin-embedded human tissues were procured from ESCC patients, encompassing 100 ESCC tissues and 100 cancer-adjacent normal (CAN) tissues. CD34 and D2-40 were utilized as markers for microvessel endothelial cells and lymphatic vessel endothelial cells, respectively. Microvascular density (MVD) and lymphatic vessel density (LVD) were evaluated through immunohistochemical quantification. We found that tumor tissues in ESCC patients had significantly higher MVD and LVD than cancer-adjacent normal (CAN) tissues. High MVD and LVD were associated with lymph node metastasis and advanced tumor clinical stages. Additionally, both high MVD and high LVD were strongly linked to poorer prognosis among cancer patients. Furthermore, a positive correlation was found between high MVD and high LVD (p < 0.05). The presence of these markers individually indicated a worse prognosis, with their combined assessment showcasing enhanced prognostic value. Overall, the increased MVD and LVD indicates higher invasion and metastasis of ESCC, closely correlating with unfavorablefor poor prognosis of ESCC patients.

AI-Powered Segmentation of Invasive Carcinoma Regions in Breast Cancer Immunohistochemical Whole-Slide Images.

The automation of quantitative evaluation for breast immunohistochemistry (IHC) plays a crucial role in reducing the workload of pathologists and enhancing the objectivity of diagnoses. However, current methods face challenges in achieving fully automated immunohistochemistry quantification due to the complexity of segmenting the tumor area into distinct ductal carcinoma in situ (DCIS) and invasive carcinoma (IC) regions. Moreover, the quantitative analysis of immunohistochemistry requires a specific focus on invasive carcinoma regions. In this study, we propose an innovative approach to automatically identify invasive carcinoma regions in breast cancer immunohistochemistry whole-slide images (WSIs). Our method leverages a neural network that combines multi-scale morphological features with boundary features, enabling precise segmentation of invasive carcinoma regions without the need for additional H&E and P63 staining slides. In addition, we introduced an advanced semi-supervised learning algorithm, allowing efficient training of the model using unlabeled data. To evaluate the effectiveness of our approach, we constructed a dataset consisting of 618 IHC-stained WSIs from 170 cases, including four types of staining (ER, PR, HER2, and Ki-67). Notably, the model demonstrated an impressive intersection over union (IoU) score exceeding 80% on the test set. Furthermore, to ascertain the practical utility of our model in IHC quantitative evaluation, we constructed a fully automated Ki-67 scoring system based on the model's predictions. Comparative experiments convincingly demonstrated that our system exhibited high consistency with the scores given by experienced pathologists. Our developed model excels in accurately distinguishing between DCIS and invasive carcinoma regions in breast cancer immunohistochemistry WSIs. This method paves the way for a clinically available, fully automated immunohistochemistry quantitative scoring system.

Lethal lymphocytic myocarditis-an underestimated diagnosis in infancy and childhood?

In the past, histological diagnosis of (post-)viral myocarditis was based on the so-called Dallas criteria, which have been criticized because of high interobserver variability and sampling error. Immunohistochemical qualification and quantification of interstitial intramyocardial leucocytes was established and standard values concerning adults were published. Fatal casualties due to aviral myocarditis are rare as far as babies and children are concerned (sudden unexpected death in infancy; SUDI). Cases of sudden unexpected death in the first year of life are frequently regarded as sudden infant death syndrome (SIDS). To diagnose myocarditis when there are only single focal lymphocytic infiltrates in the myocardium, the number of samples taken by autopsy is relevant. But even in babies, immunohistochemical qualification and quantification of interstitial lymphocytes and macrophages can lead to standard values allowing diagnosis of myocarditis. Depending on the course of aviral infection, molecular pathological detection of viral genome in the myocardium is possible to support the diagnosis. Using the mentioned methods gradually, there are more cases of suspected SIDS, which are in fact cases of virus-induced myocarditis as cause of death. Primary enteroviruses (coxsackie viruses) and adenoviruses were found but also Epstein-Barr virus and PVB-19.

Unsupervised machine learning models reveal predictive clinical markers of glioblastoma patient survival using white blood cell counts prior to initiating chemoradiation.

Glioblastoma is a malignant brain tumor requiring careful clinical monitoring even after primary management. Personalized medicine has suggested the use of various molecular biomarkers as predictors of patient prognosis or factors utilized for clinical decision-making. However, the accessibility of such molecular testing poses a constraint for various institutes requiring identification of low-cost predictive biomarkers to ensure equitable care. We collected retrospective data from patients seen at Ohio State University, University of Mississippi, Barretos Cancer Hospital (Brazil), and FLENI (Argentina) who were managed for glioblastoma-amounting to 581 patient records documented using REDCap. Patients were evaluated using an unsupervised machine learning approach comprised of dimensionality reduction and eigenvector analysis to visualize the inter-relationship of collected clinical features. We discovered that the serum white blood cell (WBC) count of a patient during baseline planning for treatment was predictive of overall survival with an over 6-month median survival difference between the upper and lower quartiles of WBC count. By utilizing an objective PD-L1 immunohistochemistry quantification algorithm, we were further able to identify an increase in PD-L1 expression in glioblastoma patients with high serum WBC counts. These findings suggest that in a subset of glioblastoma patients the incorporation of WBC count and PD-L1 expression in the brain tumor biopsy as simple biomarkers predicting glioblastoma patient survival. Moreover, machine learning models allow the distillation of complex clinical data sets to uncover novel and meaningful clinical relationships.

Vulvo-vaginal epithelial tumors in mares: A preliminary investigation on epithelial-mesenchymal transition and tumor-immune microenvironment.

Vulvo-vaginal epithelial tumors are uncommon in mares, and data on the epithelial-to-mesenchymal transition (EMT) and the tumor-immune microenvironment (TIME) are still lacking. This is a study investigating the equus caballus papillomavirus type 2 (EcPV2) infection state as well as the EMT process and the tumor microenvironment in vulvo-vaginal preneoplastic/ benign (8/22) or malignant (14/22) epithelial lesions in mares. To do this, histopathological, immunohistochemical, transcriptomic, in situ hybridization, and correlation analyses were carried out. Immunohistochemistry quantification showed that cytoplasmic E-cadherin and β-catenin expression as well as nuclear β-catenin expression were features of malignant lesions, while benign/preneoplastic lesions were mainly characterized by membranous E-cadherin and β-catenin expression. Despite this, there were no differences between benign and malignant equine vulvo-vaginal lesions in the expression of downstream genes involved in the canonical and noncanonical wnt/β-catenin pathways. In addition, malignant lesions were characterized by a lower number of cells with cytoplasmic cytokeratin expression as well as a slightly higher cytoplasmic vimentin immunolabeling. The TIME of malignant lesions was characterized by more numerous CD204+ M2-polarized macrophages. Altogether, our results support the hypothesis that some actors in TIME such as CD204+ M2-polarized macrophages may favor the EMT process in equine vulvo-vaginal malignant lesions providing new insights for future investigations in the field of equine EcPV2-induced genital neoplastic lesions.

Abstract PO-040: Comparing digital image analysis with a manual scoring approach for quantification of p63 and BRCA1 protein expression in oropharyngeal squamous cell carcinoma

Abstract In oropharyngeal squamous cell carcinomas (OPSCC) there is overexpression of p63. We previously identified a link between p63 and BRCA1 in OPSCC, both at a gene and protein level. However, interpretation of biomarkers based on protein expression identified using immunohistochemistry can be subject to interobserver variability. We aimed to explore the option of digital image analysis as an alternative approach to immunohistochemical protein quantification. Herein, we compare manual histological interpretation of p63 and BRCA1 expression in the context of HPV status with digital image analysis. Representative samples of a clinically annotated cohort of OPSCC (n=191) were arranged in triplicate tissue microarrays (TMA) and stained immunohistochemically for p63 (p63NCL and p63DN) and BRCA1 (D-9 and Ab1). RNA in situ hybridization for a cocktail of 18 high-risk HPV genotypes (HR-18 HPV) was used to determine HPV status. Cases were scored manually using at least two independent scorers to generate consensus Q scores. Each TMA slide was digitally scanned. These images were imported into QuPath version 0.2.3, which was used to quantify the expression of each biomarker and generate digital H scores. Statistical analysis was conducted using R version 4.2.3 and GraphPad Prism5. Spearman’s Rank correlation was used to compare the digital and manual scores for each biomarker. Kaplan-Meier curves and log rank tests were used for survival analysis. Preliminary analysis showed a strong correlation between manual scoring methods and digital scores for each of the four biomarkers: p63NCL (rs=0.77, p&amp;lt;0.0001); p63DN (rs=0.72, p&amp;lt;0.0001); BRCA D9 (rs=0.75, p&amp;lt;0.0001) and BRCA AB1 (rs=0.84, p&amp;lt;0.0001). We identified a subgroup of HPV negative patients with low p63NCL expression and high BRCA D9 expression that had poor 5-year overall survival (p&amp;lt;0.0001). The process of digital quantification is more labour intensive than one might anticipate. It requires significant pre-processing to remove artefacts prior to obtaining a computer-generated H score. In contrast manual Q scoring allows immediate assessment. In addition, the BRCA D-9 antibody had non-specific staining, highlighting darkly staining “dendritic-like” cells which complicated digital assessment. The results show the effectiveness and reproducibility of digital pathology scoring methods for antibody quantification when compared with traditional manual scoring methods. However manual scoring methods presently used by pathologists are significantly more time efficient when compared to newer digital techniques. There is a need for improved or automated pre-processing techniques to remove some of the pitfalls associated with this approach for future studies validating use of combined low p63NCL expression and high BRCA D9 expression to predict outcome in patients with OPSCC. Citation Format: Laura Graham, Stephanie Craig, Kris McCombe, Stephen McQuaid, Simon McDade, Jacqueline James. Comparing digital image analysis with a manual scoring approach for quantification of p63 and BRCA1 protein expression in oropharyngeal squamous cell carcinoma [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Innovating through Basic, Clinical, and Translational Research; 2023 Jul 7-8; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2023;29(18_Suppl):Abstract nr PO-040.

Ubiquinol preserves immune cells in gamma-irradiated rats: Role of autophagy and apoptosis in splenic tissue

Radiation has been applied in cancer treatment to eradicate tumors and displayed great therapeutic benefits for humans. However, it is associated with negative impacts on normal cells, not only cancer cells. Irradiation can trigger cell death through several mechanisms, such as apoptosis, necrosis, and autophagy. This study aimed to investigate the radioprotective efficacy of ubiquinol against radiation-induced splenic tissue injury in animals and the related involved mechanisms. Animals were classified into four groups: group 1 (normal untreated rats) received vehicle 5 % Tween 80; group 2 received 7 Gy γ-radiation; group 3 received 10 mg/Kg oral ubiquinol post-irradiation; and group 4 received 10 mg/Kg oral ubiquinol before and after (pre/post-) irradiation. Ubiquinol restored the spleen histoarchitecture, associated with improved immunohistochemical quantification of B and T lymphocyte markers and ameliorated hematological alterations induced by irradiation. Such effects may be due to an enhanced antioxidant pathway through stimulation of p62, Nrf2, and GSH, associated with reduced Keap1 and MDA. Moreover, ubiquinol decreased mTOR, thus enhanced autophagy markers viz. LC3-II. Furthermore, ubiquinol showed an antiapoptotic effect by enhancing Bcl-2 and reducing caspase-3 and Bax. Consequently, ubiquinol exerts a splenic-protective effect against irradiation via enhancing antioxidant, autophagic, and survival pathways.

Reproducibility in PD-L1 Immunohistochemistry Quantification through the Tumor Proportion Score and the Combined Positive Score: Could Dual Immunostaining Help Pathologists?

We studied the pathologists’ agreements in quantifying PD-L1 expression through the tumor proportion score (TPS) and the combined positive score (CPS) using single PD-L1 immunohistochemistry (S-IHC) and double immunohistochemistry (D-IHC) combining PD-L1 staining and tumor cell markers. S-IHC and D-IHC were applied to 15 cancer samples to generate 60 digital IHC slides (30 whole slides images and 30 regions of interest of 1 mm2) for PD-L1 expression quantification using both TPS and CPS, twice by four pathologists. Agreements were estimated calculating intraclass correlation coefficients (ICC). Both S-IHC and D-IHC slides analyses resulted in excellent (for TPS, ICC &gt; 0.9) to good (for CPS, ICC &gt; 0.75) inter- and intra-pathologist agreements with slightly higher ICC with D-IHC than with S-IHC. S-IHC resulted in higher TPS and CPS than D-IHC (+5.6 and +6.1 mean differences, respectively). High reproducibility in the quantification of PD-L1 expression is attainable using S-IHC and D-IHC.

Human Adipose-Derived Stem Cells Reduce Cellular Damage after Experimental Spinal Cord Injury in Rats.

Traumatic spinal cord injury (SCI) is a devastating condition without an effective therapy. Cellular therapies are among the promising treatment strategies. Adult stem cells, such as mesenchymal stem cells, are often used clinical research for their immunomodulatory and regenerative potential. This study aimed to evaluate the effect of human adipose tissue-derived stem cells (ADSC) infusion through the cauda equina in rats with SCI. The human ADSC from bariatric surgery was isolated, expanded, and characterized. Wistar rats were subjected to blunt SCI and were divided into four groups. Two experimental groups (EG): EG1 received one ADSC infusion after SCI, and EG2 received two infusions, the first one after SCI and the second infusion seven days after the injury. Control groups (CG1 and CG2) received infusion with a culture medium. In vivo, cell tracking was performed 48 h and seven days after ADSC infusion. The animals were followed up for 40 days after SCI, and immunohistochemical quantification of myelin, neurons, and astrocytes was performed. Cellular tracking showed cell migration towards the injury site. ADSC infusion significantly reduced neuronal loss, although it did not prevent the myelin loss or enhance the area occupied by astrocytes compared to the control group. The results were similar when comparing one or two cell infusions. The injection of ADSC distal to the injured area was shown to be a safe and effective method for cellular administration in spinal cord injury.

Abstract CT095: Update: a phase 1/2, open-label study to assess safety, tolerability, biodistribution, radiation dosimetry and PET imaging characteristics of [18F]FPyGal in comparison to in-vitro diagnostic for the assessment of senescence in oncological patients (NCT04536454)

Abstract It is well established that senescence of cancer cells can be induced by treatment with classical cytotoxic therapies but also by molecularly targeted therapies or immunotherapies, a phenomenon referred to as therapy induced senescence (TIS). Occurrence of intratumoral senescence harbors broad therapeutic implications and may limit the prognosis of cancer patients, as senescent cells, via their senescence associated secretory phenotype (SASP), can suppress anti-tumor immune responses and may increase the metastatic potential of non-senescent cancer cells. Preclinical data suggest that an eradication of senescent cells (senolytic therapies) or an application of SASP modulating therapies might improve the outcome of systemic cancer therapies, however, as a prerequisite to guide such approaches, robust and non-invasive modalities to visualize and quantify intratumoral senescence are needed. We recently reported on the safety evaluation of the novel Positron-Emission-Tomography (PET) tracer [18F]FPyGal, a radiolabeled substrate of senescence-associated ꞵ-galactosidase in healthy volunteers (AACR 2022, #7958). In summary, our data showed that the use of [18F]FPyGal is safe and well-tolerated in the described human study population. In the second stage of our trial, we are now investigating the concordance of histopathological senescence markers with [18F]FPyGal senescence signals in i) rectum cancer-, ii) non-small cell lung cancer- and iii) adenocarcinoma of the esophagogastric junction (AEG) patients, who are undergoing neoadjuvant therapy. Here, we report on patients from the rectum cancer cohort of the trial. [18F]FPyGal PET imaging was done before and after administration of neoadjuvant radiochemotherapy (RCTx). [18F]FPyGal PET signal was correlated with immunohistochemical senescence markers (p16, p21, p53) and quantification of SA-ß-gal (Senescence-associated beta-galactosidase) positive cells in biopsy materials (pre-therapy) and surgical resection materials (post-therapy). Expectedly, senescent cells were only detected at very low frequency in therapy naïve tumors and the lack of histological detection of senescence correlated with negativity in [18F]FPyGal imaging. In stark contrast, homogenous senescence, quantified with the indicated senescence markers, was detected in the majority of cancer cells after RCTx. Interestingly, in one rectum carcinoma, which underwent a full remission after RCTx, senescence of stroma cells in the area of the former tumor bed was detected by PET imaging and histologically. Collectively, our data indicate the utility of [18F]FPyGal PET imaging to non-invasively detect senescence. Future trials using [18F]FPyGal to guide oncological therapy, e.g. to apply senolytic drugs in a personalized manner, are warranted. Citation Format: Christian LaFougere, Brigitte Gueckel, Helmut Dittmann, Nils Trautwein, Martina Hinterleitner, Jonathan Cotton, Gerald Reischl, Gabriele Kienzle, Stephan Singer, Cihan Gani, Ulrich Lauer, Bernd Pichler, Lars Zender. Update: a phase 1/2, open-label study to assess safety, tolerability, biodistribution, radiation dosimetry and PET imaging characteristics of [18F]FPyGal in comparison to in-vitro diagnostic for the assessment of senescence in oncological patients (NCT04536454) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT095.

Automated immunohistochemical quantification of hypoxia biomarkers shows correlation with dysplastic epithelial changes.

Dysregulation of the hypoxia-aerobic system has been postulated in various malignancies. Nonetheless, the contribution of hypoxia to oral carcinogenesis is yet to be elucidated. Understanding this mechanism is important for improving diagnostic tools and targeted therapies. This study aimed to assess the dysregulation of hypoxia-related factors during different stages of oral squamous cell carcinoma (OSCC) development. Ninety-two patients diagnosed clinically with oral leukoplakia or OSCC were included and classified according to their histopathological diagnoses. A panel of seven hypoxia-related antibodies were used for immunohistochemical staining of each case. Automated quantification of immunostaining was used for objective reporting. Microvessel density was also assessed. Significant associations were reported for non-dysplastic epithelial changes and malignancy for Glut1, HIF-1α, vascular endothelial growth factor, and signal transducer and activator of transcription 3(p< 0.005). Similarly, microvessel density significantly increased with the severity of epithelial disorders. A multiple regression model including the H-score of HIF-1α and microvessel density could statistically significantly predict the grade of epithelial disorder (p< 0.005). The associated diagnostic accuracy of this approach was 88%. Hypoxia-associated events are observed during early epithelial dysplastic changes and have a potential role in oral carcinogenesis. The level of hypoxia may assist in stratifying the severity of epithelial changes among patients with oral leukoplakia.

Clinicopathological classification of immune checkpoint inhibitor-associated myocarditis: possible refinement by measuring macrophage abundance

BackgroundImmune checkpoint inhibitor (ICI) myocarditis is associated with high morbidity and mortality. While endomyocardial biopsy (EMB) is considered a gold standard for diagnosis, the sensitivity of EMB is not well defined. Additionally, the pathological features that correlate with the clinical diagnosis of ICI-associated myocarditis remain incompletely understood.MethodsWe retrospectively identified and reviewed the clinicopathological features of 26 patients with suspected ICI-associated myocarditis based on institutional major and minor criteria. Seventeen of these patients underwent EMB, and the histopathological features were assessed by routine hematoxylin and eosin (H&E) staining and immunohistochemical (IHC) staining for CD68, a macrophage marker.ResultsOnly 2/17 EMBs obtained from patients with suspected ICI myocarditis satisfied the Dallas criteria. Supplemental IHC staining and quantification of CD68+ macrophages identified an additional 7 patients with pathological features of myocardial inflammation (> 50 CD68+ cells/HPF). Macrophage abundance positively correlated with serum Troponin I (P = 0.010) and NT-proBNP (N-terminal pro-brain natriuretic peptide, P = 0.047) concentration. Inclusion of CD68 IHC could have potentially changed the certainty of the diagnosis of ICI-associated myocarditis to definite in 6/17 cases.ConclusionsWhile the Dallas criteria can identify a subset of ICI-associated myocarditis patients, quantification of macrophage abundance may expand the diagnostic role of EMB. Failure to meet the traditional Dallas Criteria should not exclude the diagnosis of myocarditis.

Noninferiority of Artificial Intelligence–Assisted Analysis of Ki-67 and Estrogen/Progesterone Receptor in Breast Cancer Routine Diagnostics

Image analysis assistance with artificial intelligence (AI) has become one of the great promises over recent years in pathology, with many scientific studies being published each year. Nonetheless, and perhaps surprisingly, only few image AI systems are already in routine clinical use. A major reason for this is the missing validation of the robustness of many AI systems: beyond a narrow context, the large variability in digital images due to differences in preanalytical laboratory procedures, staining procedures, and scanners can be challenging for the subsequent image analysis. Resulting faulty AI analysis may bias the pathologist and contribute to incorrect diagnoses and, therefore, may lead to inappropriate therapy or prognosis. In this study, a pretrained AI assistance tool for the quantification of Ki-67, estrogen receptor (ER), and progesterone receptor (PR) in breast cancer was evaluated within a realistic study set representative of clinical routine on a total of 204 slides (72 Ki-67, 66 ER, and 66 PR slides). This represents the cohort with the largest image variance for AI tool evaluation to date, including 3 staining systems, 5 whole-slide scanners, and 1 microscope camera. These routine cases were collected without manual preselection and analyzed by 10 participant pathologists from 8 sites. Agreement rates for individual pathologists were found to be 87.6% for Ki-67 and 89.4% for ER/PR, respectively, between scoring with and without the assistance of the AI tool regarding clinical categories. Individual AI analysis results were confirmed by the majority of pathologists in 95.8% of Ki-67 cases and 93.2% of ER/PR cases. The statistical analysis provides evidence for high interobserver variance between pathologists (Krippendorff's α, 0.69) in conventional immunohistochemical quantification. Pathologist agreement increased slightly when using AI support (Krippendorff α, 0.72). Agreement rates of pathologist scores with and without AI assistance provide evidence for the reliability of immunohistochemical scoring with the support of the investigated AI tool under a large number of environmental variables that influence the quality of the diagnosed tissue images.

Bovine meat and milk factor protein expression in tumor-free mucosa of colorectal cancer patients coincides with macrophages and might interfere with patient survival.

Bovine milk and meat factors (BMMFs) are plasmid-like DNA molecules isolated from bovine milk and serum, as well as the peritumor of colorectal cancer (CRC) patients. BMMFs have been proposed as zoonotic infectious agents and drivers of indirect carcinogenesis of CRC, inducing chronic tissue inflammation, radical formation and increased levels of DNA damage. Data on expression of BMMFs in large clinical cohorts to test an association with co-markers and clinical parameters were not previously available and were therefore assessed in this study. Tissue sections with paired tumor-adjacent mucosa and tumor tissues of CRC patients [individual cohorts and tissue microarrays (TMAs) (n= 246)], low-/high-grade dysplasia (LGD/HGD) and mucosa of healthy donors were used for immunohistochemical quantification of the expression of BMMF replication protein (Rep) and CD68/CD163 (macrophages) by co-immunofluorescence microscopy and immunohistochemical scoring (TMA). Rep was expressed in the tumor-adjacent mucosa of 99% of CRC patients (TMA), was histologically associated with CD68+/CD163+ macrophages and was increased in CRC patients when compared to healthy controls. Tumor tissues showed only low stromal Rep expression. Rep was expressed in LGD and less in HGD but was strongly expressed in LGD/HGD-adjacent tissues. Albeit not reaching statistical significance, incidence curves for CRC-specific death were increased for higher Rep expression (TMA), with high tumor-adjacent Rep expression being linked to the highest incidence of death. BMMF Rep expression might represent a marker and early risk factor for CRC. The correlation between Rep and CD68 expression supports a previous hypothesis that BMMF-specific inflammatory regulations, including macrophages, are involved in the pathogenesis of CRC.