An extensive immunohistochemical analysis of 290 ovarian adult granulosa cell tumors with 29 markers.

The current knowledge about the immunohistochemical features of adult granulosa cell tumor (AGCT) is mostly limited to the "traditional" immunohistochemical markers of sex cord differentiation, such as inhibin, calretinin, FOXL2, SF1, and CD99. Knowledge about the immunohistochemical markers possibly used for predictive purpose is limited. In our study, we focused on the immunohistochemical examination of 290 cases of AGCT classified based on strict diagnostic criteria, including molecular testing. The antibodies used included 12 of the "diagnostic" antibodies already examined in previous studies, 10 antibodies whose expression has not yet been examined in AGCT, and 7 antibodies with possible predictive significance, including the expression of HER2, PD-L1, CTLA4, and 4 mismatch repair (MMR) proteins. The results of our study showed expression of FOXL2, SF1, CD99, inhibin A, calretinin, ER, PR, AR, CKAE1/3, and CAIX in 98%, 100%, 90%, 78%, 45%, 41%, 94%, 82%, 26%, and 9% of AGCT, respectively. GATA3, SATB2, napsin A, MUC4, TTF1, and CD44 were all negative. PTEN showed a loss of expression in 71% of cases and DPC4 in 4% of cases. The aberrant staining pattern (overexpression) of p53 was found in 1% (3/268) of cases, 2 primary tumors, and 1 recurrent case. Concerning the predictive markers, the results of our study showed that AGCT is microsatellite stable, do not express PD-L1, and are HER2 negative. The CTLA4 expression was found in almost 70% of AGCT tumor cells.

Simple 3D spheroid cell culture model for studies of prion infection.

Mouse neuronal CAD 5 cell line effectively propagates various strains of prions. Previously, we have shown that it can also be differentiated into the cells morphologically resembling neurons. Here, we demonstrate that CAD 5 cells chronically infected with prions undergo differentiation under the same conditions. To make our model more realistic, we triggered the differentiation in the 3D culture created by gentle rocking of CAD 5 cell suspension. Spheroids formed within 1 week and were fully developed in less than 3 weeks of culture. The mature spheroids had a median size of ~300 µm and could be cultured for up to 12 weeks. Increased expression of differentiation markers GAP 43, tyrosine hydroxylase, ß-III-tubulin and SNAP 25 supported the differentiated status of the spheroid cells. The majority of them were found in the G0/G1 phase of the cell cycle, which is typical for differentiated cells. Moreover, half of the PrPC on the cell membrane was N-terminally truncated, similarly as in differentiated CAD 5 adherent cells. Finally, we demonstrated that spheroids could be created from prion-infected CAD 5 cells. The presence of prions was verified by immunohistochemistry, western blot and seed amplification assay. We also confirmed that the spheroids can be infected with the prions de novo. Our 3D culture model of differentiated CAD 5 cells is low cost, easy to produce and cultivable for weeks. We foresee its possible use in the testing of anti-prion compounds and future studies of prion formation dynamics.

Neutrophil Extracellular Traps and Thrombolysis Resistance: New Insights for Targeting Therapies.

BACKGROUND: Thrombosis is linked to neutrophil release of neutrophil extracellular traps (NETs). NETs are proposed as a mechanism of resistance to thrombolysis. This study intends to analyze the composition of thrombi retrieved after mechanical thrombectomy, estimate the age and organization of thrombi, and evaluate associations with the use of thrombolysis, antiplatelets, and heparin. METHODS: This retrospective observational study involved 72 samples (44 from cerebral and 28 coronary arteries), which were stained with hematoxylin and eosin, anti-NE (neutrophil elastase) antibody, and anti-histone H2B (histone H2B) antibody, representing different components in NET formation, all detectable during the later stages of NETosis, for histochemical and digital quantification of NET content. The histological and morphological evaluations of the specimens were correlated, through univariate and mediation analyses, with clinical information and therapy administered before intervention. RESULTS: The results demonstrated that the composition of cerebral and coronary thrombi differs, and there were significantly more lytic cerebral thrombi than coronary thrombi (66% versus 14%; P=0.005). There was a considerably higher expression of NETs in the cerebral thrombi as testified by the higher expression of H2B (P=0.031). Thrombolysis was remarkably associated with higher NE positivity (average marginal effect, 6.461 [95% CI, 0.7901-12.13]; P=0.02555), regardless of the origin of thrombi. There was no notable association between the administration of antiaggregant therapy/heparin and H2B/NE amount when adjusted for the thrombus location. Importantly, the age of the thrombus was the only independent predictor of NET content without any mediation of the thrombolytic treatment (P=0.014). CONCLUSIONS: The age of the thrombus is the driving force for NET content, which correlates with impaired clinical outcomes. The therapy that is currently administered does not modify NET content. This study supports the need to investigate new pharmacological approaches added to thrombolysis to prevent NET formation or enhance their disruption, such as recombinant human DNase I (deoxyribonuclease I).

Detection of prions in matching post-mortem skin and cerebrospinal fluid samples using second-generation real-time quaking-induced conversion assay.

Real-time quaking-induced conversion assay (RT-QuIC) exploits templating activity of pathogenic prion protein for ultrasensitive detection of prions. We have utilized second generation RT-QuIC assay to analyze matching post-mortem cerebrospinal fluid and skin samples of 38 prion disease patients and of 30 deceased neurological controls. The analysis of cerebrospinal fluid samples led to 100% sensitivity and 100% specificity, but some samples had to be diluted before the analysis to alleviate the effect of present RT-QuIC inhibitors. The analysis of the corresponding skin samples provided 89.5% sensitivity and 100% specificity. The median seeding dose present in the skin was one order of magnitude higher than in the cerebrospinal fluid, despite the overall fluorescent signal of the skin samples was comparatively lower. Our data support the use of post-mortem cerebrospinal fluid for confirmation of prion disease diagnosis and encourage further studies of the potential of skin biopsy samples for intra-vitam prion diseases´ diagnostics.

The Spectrum of Fusions Occurring in Non-Smooth Muscle Mesenchymal Uterine Tumors: A Review of the Current Knowledge.

CONTEXT.­: Non-smooth muscle uterine sarcomas are mostly represented by low-grade endometrial stromal sarcoma. However, several other rare, distinct types of uterine sarcoma are recognized, including high-grade endometrial stromal sarcoma, tumors with kinase fusions, uterine tumors resembling ovarian sex cord tumors, soft tissue-type sarcoma, and emerging entities such as KAT6A/B-rearranged tumors. The landscape of uterine sarcomas has changed, mostly because of the increasing knowledge concerning their molecular aberrations. OBJECTIVE.­: To offer a comprehensive review of the literature focusing on fusions occurring in other than smooth muscle mesenchymal uterine tumors with respect to their type, frequency, and overlap between diagnostic categories and entities. DATA SOURCES.­: The data were mined from the PubMed/MEDLINE database covering the time period from January 1988 to June 2023. In total, 156 studies focusing on the problematics of fusions occurring in non-smooth muscle mesenchymal uterine tumors were selected, and thus became the basis for this review. CONCLUSIONS.­: One hundred ten fusions were identified in 703 tumors. The diagnostic significance of the molecular aberrations occurring in these tumors can be unclear in some cases. This can be related to the rare aberrations with a limited number of reported cases. Additionally, even well-known aberrations considered as specific for a certain distinct entity can occur in more lesions, the biological behavior and clinical significance of which can differ substantially.

Undifferentiated Carcinoma with Osteoclast-like Giant Cells of the Pancreas: Molecular Genetic Analysis of 13 Cases.

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) of the pancreas is a rare malignancy regarded as a subvariant of pancreatic ductal carcinoma (PDAC) characterized by variable prognosis. UCOGC shows a strikingly similar spectrum of oncogenic DNA mutations to PDAC. In the current work, we analyzed the landscape of somatic mutations in a set of 13 UCOGC cases via next-generation sequencing (NGS). We detected a spectrum of pathogenic or likely pathogenic mutations similar to those observed in PDAC following previously published results (10 KRAS, 9 TP53, 4 CDKN2A, and 1 SMAD4, CIC, GNAS, APC, ATM, NF1, FBXW7, ATR, and FGFR3). Our results support the theory that UCOGC is a variant of PDAC, despite its unique morphology; however, a UCOGC-specific genomic signature as well as predictive markers remain mainly unknown. Programmed death ligand 1 (PD-L1) status remains an important predictive marker based on previous studies.

Association of the combined parameters including the frequency of primary cilia, PD-L1, Smoothened protein, membranous ß-catenin and cytoplasmic ß-catenin expression with the outcome of patients with clear cell renal cell carcinoma.

AIMS: The objective of this study was to investigate the association and combined prognostic significance of the PD-L1, Smoothened protein and ß-catenin expressions in patients with clear cell renal cell carcinoma (ccRCC). METHODS: The PD-L1, Smoothened protein and ß-catenin expression were evaluated in 104 ccRCC patients. All studied tumor samples were acquired from nephrectomy specimens of primary tumors and not from biopsies or metastases. An indirect immunohistochemistry using polyclonal rabbit anti-Smoothened antibody, monoclonal mouse anti-human ß-catenin-1 antibody, immunohistochemical assay PD-L1 28-8 pharmDx using monoclonal rabbit anti-PD-L1 antibody and anti-VHL (C- terminal) rabbit antibody was used. Immunohistochemistry was scored semiquantitavely. RESULTS: Median overall survival (OS) was significantly better in patients with lower PD-L1 expression (≤5%), Smoothened protein (SMO) expression (<5%) or cytoplasmic ß-catenin expression (≤75%) than in patients with higher expressions of these biomarkers (P<0.001, P=0.047, and P<0.001, respectively). Membranous ß-catenin showed an opposite effect with its lower expression (≤75%) being associated with longer OS (P=0.020). There was significant association between PD-1 and PD-L1 expression (P=0.007) and significant association of tumor grade (WHO 2016) with membranous ß-catenin (P<0.001), cytoplasmic ß-catenin (P=0.005), pVHL (P=0.042), PD-L1 (P=0.049) and PD-1 (P=0.028) expression. CONCLUSION: The present study provides the first data on the potential association and combined prognostic significance of frequency of primary cilia, PD-L1, Smoothened protein and ß-catenin expression with the outcome in clear cell renal cell carcinoma.

Aneurysmal 99m Tc-HMPAO Uptake in Brain Death.

ABSTRACT: A 41-year-old man was admitted to hospital due to sudden loss of consciousness. A regional brain perfusion SPECT/low-dose CT showed abnormal 99m Tc-HMPAO uptake in the right hemisphere frontotemporally without any other supratentorial or infratentorial radiotracer uptake. A neuropathological examination disclosed a middle cerebral artery aneurysm. Presumably, vessel wall fibrosis prevented collapse. Multiple transmural dissections of the fibrotic aneurysmal wall were the source of the subarachnoid hemorrhage. This interesting image shows that radiotracer accumulation in cerebral artery aneurysms can be a diagnostic pitfall in brain death scintigraphy assessment.

Somatic Genomic and Transcriptomic Characterization of Primary Ovarian Serous Borderline Tumors and Low-Grade Serous Carcinomas.

Low-grade serous carcinoma (LGSC) may develop from serous borderline tumor (SBT) tissue, where the micropapillary type (mSBT) presents the highest risk for progression. The sensitivity of LGSC to standard chemotherapy is limited, so alternative therapeutic approaches, including targeted treatment, are needed. However, knowledge about the molecular landscape of LGSC and mSBT is limited. A sample set of 137 pathologically well-defined cases (LGSC, 97; mSBT, 40) was analyzed using capture DNA next-generation sequencing (727 genes) and RNA next-generation sequencing (147 genes) to show the landscape of somatic mutations, gene fusions, expression pattern, and prognostic and predictive relevance. Class 4/5 mutations in the main driver genes (KRAS, BRAF, NRAS, ERBB2, USP9X) were detected in 48% (14/29) of mSBT cases and 63% (47/75) of LGSC cases. The USP9X mutation was detected in only 17% of LGSC cases. RNA next-generation sequencing revealed gene fusions in 6 of 64 LGSC cases (9%) and 2 of 33 mSBT cases (9%), and a heterogeneous expression profile across LGSC and mSBT. No molecular characteristics were associated with greater survival. The somatic genomic and transcriptomic profiles of 35 mSBT and 85 LGSC cases are compared for the first time. Candidate oncogenic gene fusions involving BRAF, FGFR2, or NF1 as a fusion partner were identified. Molecular testing of LGSC may be used in clinical practice to reveal therapeutically significant targets.

Utilizing neurodegenerative markers for the diagnostic evaluation of amyotrophic lateral sclerosis.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by progressive deterioration of upper and lower motor neurons. A definitive diagnostic test or biomarker for ALS is currently unavailable, leading to a diagnostic delay following the onset of initial symptoms. Our study focused on cerebrospinal fluid (CSF) concentrations of clusterin, tau protein, phosphorylated tau protein, and beta-amyloid1-42 in ALS patients and a control group. METHODS: Our study involved 54 ALS patients and 58 control subjects. Among the ALS patients, 14 presented with bulbar-onset ALS, and 40 with limb-onset ALS. We quantified biomarker levels using enzyme-linked immunosorbent assay (ELISA) and compared the results using the Mann-Whitney U-test. RESULTS: Significant elevations in neurodegenerative markers, including tau protein (p < 0.0001), phosphorylated tau protein (p < 0.0001), and clusterin (p = 0.038), were observed in ALS patients compared to controls. Elevated levels of tau protein and phosphorylated tau protein were also noted in both bulbar and limb-onset ALS patients. However, no significant difference was observed for beta-amyloid1-42. ROC analysis identified tau protein (AUC = 0.767) and p-tau protein (AUC = 0.719) as statistically significant predictors for ALS. CONCLUSION: Our study demonstrates that neurodegenerative marker levels indicate an ongoing neurodegenerative process in ALS. Nonetheless, the progression of ALS cannot be predicted solely based on these markers. The discovery of a specific biomarker could potentially complement existing diagnostic criteria for ALS.

Biomolecules to Biomarkers? U87MG Marker Evaluation on the Path towards Glioblastoma Multiforme Pathogenesis.

The heterogeneity of the glioma subtype glioblastoma multiforme (GBM) challenges effective neuropathological treatment. The reliance on in vitro studies and xenografted animal models to simulate human GBM has proven ineffective. Currently, a dearth of knowledge exists regarding the applicability of cell line biomolecules to the realm of GBM pathogenesis. Our study's objectives were to address this preclinical issue and assess prominin-1, ICAM-1, PARTICLE and GAS5 as potential GBM diagnostic targets. The methodologies included haemoxylin and eosin staining, immunofluorescence, in situ hybridization and quantitative PCR. The findings identified that morphology correlates with malignancy in GBM patient pathology. Immunofluorescence confocal microscopy revealed prominin-1 in pseudo-palisades adjacent to necrotic foci in both animal and human GBM. Evidence is presented for an ICAM-1 association with degenerating vasculature. Significantly elevated nuclear PARTICLE expression from in situ hybridization and quantitative PCR reflected its role as a tumor activator. GAS5 identified within necrotic GBM validated this potential prognostic biomolecule with extended survival. Here we present evidence for the stem cell marker prominin-1 and the chemotherapeutic target ICAM-1 in a glioma animal model and GBM pathology sections from patients that elicited alternative responses to adjuvant chemotherapy. This foremost study introduces the long non-coding RNA PARTICLE into the context of human GBM pathogenesis while substantiating the role of GAS5 as a tumor suppressor. The validation of GBM biomarkers from cellular models contributes to the advancement towards superior detection, therapeutic responders and the ultimate attainment of promising prognoses for this currently incurable brain cancer.

Neuroendocrine Marker Expression in Primary Non-neuroendocrine Epithelial Tumors of the Ovary: A Study of 551 Cases.

Expression of neuroendocrine (NE) markers in primary ovarian non-NE epithelial tumors has rarely been evaluated. The aim of our study was to evaluate the expression of the most widely used NE markers in these neoplasms and to determine any prognostic significance of NE marker expression. The cohort consisted of 551 primary ovarian tumors, including serous borderline tumors, low-grade serous carcinomas, high-grade serous carcinomas (HGSC), clear cell carcinomas, endometroid carcinomas, mucinous borderline tumors, and mucinous carcinomas. Immunohistochemical analysis was performed using antibodies against INSM1, synaptophysin, chromogranin, and CD56 on tissue microarray. Positivity for INSM1, synaptophysin, chromogranin, and CD56 was most frequently observed in mucinous tumors (48.7%, 26.0%, 41.5%, and 100%, respectively). The positivity for these NE markers was mostly restricted to nonmucinous elements distributed throughout the tumor. The mucinous borderline tumor and mucinous carcinomas groups had similar proportions of positivity (mucinous borderline tumor: 53%, mucinous carcinomas: 39%). In the other tumor types, except for HGSC, there was only focal expression (5%-10%) or negativity for NE markers. HGSC showed high CD56 expression (in 26% of cases). Survival analysis was only performed for CD56 in HGSC as this was the only group with sufficient positive cases, and it showed no prognostic significance. Except for mucinous tumors, expression of NE markers in non-NE ovarian epithelial tumors is low. CD56 expression in HGSC occurs frequently but is without diagnostic or prognostic value.

High tumour mutational burden is associated with strong PD-L1 expression, HPV negativity, and worse survival in penile squamous cell carcinoma: an analysis of 165 cases.

Penile squamous cell carcinoma (pSCC) is a rare tumour with a variable prognosis. More prognostic markers linked to mutational signatures and the tumour immune microenvironment are needed. A cohort made up of 165 invasive pSCC was retrospectively analysed using formalin-fixed, paraffin-embedded tumour tissue, focusing on tumour mutational burden (TMB), programmed death ligand 1 (PD-L1) expression, microsatellite instability (MSI), the number of tumour infiltrating lymphocytes (TILs) expressing cytotoxic T-lymphocyte-associated protein 4 (CTLA4), HPV status determined by p16 immunohistochemistry, and several traditional histopathological variables. High TMB (>10 mut/Mb) was associated with high PD-L1 expression (TPS 50-100%), and HPV-negative status. High PD-L1 expression was linked to HPV negativity, a high number of intratumoural CTLA4+ cells, and brisk lymphocytic infiltrate. High TMB was a significant predictor of shorter overall survival (OS) in both univariate and multivariate analysis when using a median cut-off value of 4.3 mut/Mb, but not when using an arbitrary cut-off of 10 mut/Mb. Low CTLA4+ cell infiltration at the tumour invasion front was a marker of shorter OS and cancer-specific survival in both univariate and multivariate analysis. PD-L1 expression had no significant impact on prognosis. Only two cases were MSI high. The results support the hypothesis of two aetiological pathways in pSCC cancerogenesis: (1) SCC linked to HPV infection characterised by low TMB, less common PD-L1 expression, and a lower number of TILs; and (2) SCC linked to chronic inflammation leading to a high number of acquired mutations (high TMB), HPV negativity, increased neoantigen production (i.e., PD-L1), and high immune cell infiltration.

RET fusion genes in pediatric and adult thyroid carcinomas: cohort characteristics and prognosis.

Thyroid cancer is associated with a broad range of different mutations, including RET (rearranged during transfection) fusion genes. The importance of characterizing RET fusion-positive tumors has recently increased due to the possibility of targeted treatment. The aim of this study was to identify RET fusion-positive thyroid tumors, correlate them with clinicopathological features, compare them with other mutated carcinomas, and evaluate long-term follow-up of patients. The cohort consisted of 1564 different thyroid tissue samples (including 1164 thyroid carcinoma samples) from pediatric and adult patients. Samples were analyzed for known driver mutations occurring in thyroid cancer. Negative samples were subjected to extensive RET fusion gene analyses using next-generation sequencing and real-time PCR. RET fusion genes were not detected in any low-risk neoplasm or benign thyroid tissue and were detected only in papillary thyroid carcinomas (PTCs), in 113/993 (11.4%) patients, three times more frequently in pediatric and adolescent patients (29.8%) than in adult patients (8.7%). A total of 20 types of RET fusions were identified. RET fusion-positive carcinomas were associated with aggressive tumor behavior, including high rates of lymph node (75.2%) and distant metastases (18.6%), significantly higher than in NTRK fusion, BRAF V600E and RAS-positive carcinomas. Local and distant metastases were also frequently found in patients with microcarcinomas positive for the RET fusions. 'True recurrences' occurred rarely (2.4%) and only in adult patients. The 2-, 5-, 10-year disease-specific survival rates were 99%, 96%, and 95%, respectively. RET fusion-positive carcinomas were associated with high invasiveness and metastatic activity, but probably due to intensive treatment with low patient mortality.

Endemic parkinsonism: clusters, biology and clinical features.

The term 'endemic parkinsonism' refers to diseases that manifest with a dominant parkinsonian syndrome, which can be typical or atypical, and are present only in a particular geographically defined location or population. Ten phenotypes of endemic parkinsonism are currently known: three in the Western Pacific region; two in the Asian-Oceanic region; one in the Caribbean islands of Guadeloupe and Martinique; and four in Europe. Some of these disease entities seem to be disappearing over time and therefore are probably triggered by unique environmental factors. By contrast, other types persist because they are exclusively genetically determined. Given the geographical clustering and potential overlap in biological and clinical features of these exceptionally interesting diseases, this Review provides a historical reference text and offers current perspectives on each of the 10 phenotypes of endemic parkinsonism. Knowledge obtained from the study of these disease entities supports the hypothesis that both genetic and environmental factors contribute to the development of neurodegenerative diseases, not only in endemic parkinsonism but also in general. At the same time, this understanding suggests useful directions for further research in this area.

Cerebrospinal fluid and blood serum biomarkers in neurodegenerative proteinopathies: A prospective, open, cross-correlation study.

Neurodegenerative diseases are a broad heterogeneous group affecting the nervous system. They are characterized, from a pathophysiological perspective, by the selective involvement of a subpopulation of nerve cells with a consequent clinical picture of a disease. Clinical diagnoses of neurodegenerative diseases are quite challenging and often not completely accurate because of their marked heterogeneity and frequently overlapping clinical pictures. Efforts are being made to define sufficiently specific and sensitive markers for individual neurodegenerative diseases or groups of diseases in order to increase the accuracy and speed of clinical diagnosis. Thus said, this present research aimed to identify biomarkers in the cerebrospinal fluid (CSF) and serum (α-synuclein [α-syn], tau protein [t-tau], phosphorylated tau protein [p-tau], ß-amyloid [Aß], clusterin, chromogranin A [chromogrA], cystatin C [cyst C], neurofilament heavy chains [NFH], phosphorylated form of neurofilament heavy chains [pNF-H], and ratio of tau protein/amyloid beta [Ind tau/Aß]) that could help in the differential diagnosis and differentiation of the defined groups of α-synucleinopathies and four-repeat (4R-) tauopathies characterized by tau protein isoforms with four microtubule-binding domains. In this study, we analyzed a cohort of 229 patients divided into four groups: (1) Parkinson's disease (PD) + dementia with Lewy bodies (DLB) (n = 82), (2) multiple system atrophy (MSA) (n = 25), (3) progressive supranuclear palsy (PSP) + corticobasal syndrome (CBS) (n = 30), and (4) healthy controls (HC) (n = 92). We also focused on analyzing the biomarkers in relation to each other with the intention of determining whether they are useful in distinguishing among individual proteinopathies. Our results indicate that the proposed set of biomarkers, when evaluated in CSF, is likely to be useful for the differential diagnosis of MSA versus 4RT. However, these biomarkers do not seem to provide any useful diagnostic information when assessed in blood serum.

HER2 status as a potential predictive biomarker for ovarian clear cell carcinoma.

Ovarian clear cell carcinoma (OCCC) is a subtype of ovarian carcinoma characterized by unique biological features and highly malignant characteristics including low chemosensitivity. Therefore, new therapeutic targets are needed. These could include the downstream pathways of receptor tyrosine kinases, especially the human epidermal growth factor receptor 2 (HER2). Our main objective was to characterize the HER2 status using immunohistochemistry (IHC) and FISH on 118 OCCCs, also considering the novel paradigm of HER2-zero and HER2-low status. Other aims included determination of the association between HER2 status and survival, HER2 gene DNA and RNA NGS analysis, HER2 gene expression analysis, and correlation between IHC and gene expression in HER2-zero and HER2-low cases. Cases with HER2 overexpression/amplification accounted for 5.1% (6/118), with additional 3% harbouring HER2 gene mutation. The remaining 112 (94.9%) cases were HER2-negative. Of these, 75% were classified as HER2-zero and 25% as HER2-low. This percentage of HER2 aberrations is significant concerning their possible therapeutic influence. Cases from the HER2-zero group showed significantly better survival. Although this relationship lost statistical significance in multivariate analysis, the results have potential therapeutic significance. HER2 gene expression analysis showed a significant correlation with HER2 IHC status in the entire cohort (HER2-positive vs. HER2-negative), while in the cohort of only HER2-negative cases, the results did not reach statistical significance, suggesting that gene expression analysis would not be suitable to confirm the subdivision into HER2-low and HER2-zero. Our results also emphasize the need for standardized HER2 testing in OCCC to determine the best predictor of clinical response.

Immunohistochemical expression of PRAME in 485 cases of epithelial tubo-ovarian tumors.

Preferentially expressed antigen of melanoma (PRAME) is a cancer/testis antigen selectively expressed in somatic tissues and various solid malignant tumors and is associated with poor prognostic outcome. Our research aimed to comprehensively compare its expression in a large cohort of tubo-ovarian epithelial tumors and examine its correlation with our clinico-pathologic data, as well as to assess its potential use in diagnostics and therapy.We examined 485 cases of epithelial tubo-ovarian tumors including 107 clear cell carcinomas (CCC), 52 endometroid carcinomas (EC), 103 high grade serous carcinomas (HGSC), 119 low grade serous carcinomas (LGSC)/micropapillary variant of serous borderline tumors (mSBT), and 104 cases of mucinous carcinomas (MC)/mucinous borderline tumors (MBT). The immunohistochemical analysis was performed using TMAs.The highest levels of expression were seen in EC (60%), HGSC (62%), and CCC (56%), while expression in LGSC/mSBT (4%) and MC/MBT (2%) was rare. The clinico-pathologic correlations and survival analysis showed no prognostic significance.The results of our study showed that PRAME is neither prognostic nor a suitable ancillary marker in the differential diagnosis of tubo-ovarian epithelial tumors. Nevertheless, knowledge about the PRAME expression may be important concerning its potential predictive significance, because targeting PRAME as a potential therapeutic option is currently under investigation.