Applied Immunohistochemistry & Molecular Morphology最新文献

Aims: To investigate the staining patterns of CD10 in hepatocellular carcinoma (HCC), focal nodular hyperplasia (FNH), and intrahepatic cholangiocarcinoma (ICC).

Methods: The expression pattern of CD10 was analyzed using immunohistochemistry in HCC cases. Focal nodular hyperplasia (FNH) and intrahepatic cholangiocarcinoma (ICC) cases were also examined. CD10 staining pattern in relationship with histologic subtypes and growth patterns of HCC was also analyzed.

Results: CD10 expression was observed in 61% (64/105) of HCC cases, 100% (12/12) of FNH cases, and 31.6% (6/19) of ICC cases. Different expression patterns were noted, including cell membrane (13/64; 20.3%), luminal (9/64; 14.0%), cytoplasmic puncta (15/64; 23.4%), and canalicular (27/64; 42.3%) patterns of CD10 expression in HCC. Interestingly, CD10 membranous expression was found to be associated with steatosis changes. The observed pattern rates of CD10-positive ICC cases were 16.6% (1/6) for cell membrane, 50% (3/6) for cytoplasmic, and 33.3% (2/6) for luminal patterns; with 2 samples having a 1+ score (33.3%), 1 having a 2+ score (16.7%), and 3 having a 3+ score (50%).

Conclusions: Different CD10 expression patterns were observed in HCC, FNH, and ICC. A canalicular CD10 expression pattern does not distinguish between benign and malignant lesions in the HCC, but reduced CD10 expression or no canalicular pattern suggests that a tumor is more likely to be HCC. Contrary to previous understanding, we found that CD10 is also expressed in ICC cases.

A major goal in Alzheimer disease (AD) research is the reduction of the abnormal tau burden. Using multispectral analyses on brain tissues from humans who died of AD it was documented that neurons with hyperphosphorylated tau protein accumulate many proteins of the BCL2 family, including those that block cell turnover (eg, BCL2, MCL1, BCLXL) and those that promote cell turnover (eg, NOXA, PUMA, BAK, BAX). A mouse model of AD with the humanized hyperphosphorylated tau protein was used to test the hypothesis that shifting this balance to a pro-cell turnover milieu would reduce the tau burden with concomitant clinical improvement. Here, we show that a mouse model of AD with death at 11 to 15 months due to CNS tauopathy had a marked reduction in the tau burden after treatment with the FDA-approved drug venetoclax, which blocks BCL2. The reduction of the number of target neurons positive for hyperphosphorylated tau protein after venetoclax treatment in the brain and spinal cord neurons was 94.5% as determined by immunohistochemistry and 98.1% as documented with the modified Bielchowsky stain. The venetoclax treatment began after documented neurofibrillary tangles (NFTs) were evident and there was a concomitant reduction in neuroinflammation. The treated mice were robust until sacrificed at 13 months as compared with the untreated mice that showed unequivocal evidence of brain and spinal cord damage both clinically and at autopsy. We conclude that otherwise inexorable abnormal tau protein deposition, even after initiation, can be prevented by a drug that blocks one anti-cell turnover protein abundant in the NFTs of human AD.

Claudin 18.2 is a transmembrane protein, part of the tight-junction complex, selectively expressed in gastric epithelium. It is showing promising results as a target in advanced gastric cancer in phase 3 clinical trials using a monoclonal antibody against claudin 18.2. A systematic review on expression of claudin 18.2 in gastric cancer was performed using the PubMed database. The following search expression was used: ("Stomach Neoplasms" [Mesh]) AND (("claudin-18[TIAB]") OR ("CLDN18[TIAB]")). A total of n=99 articles were retrieved. Of those, 17 preclinical studies about claudin 18.2 expression by immunohistochemistry were selected. The results of those studies showed great variability in the criteria used for defining the thresholds for positivity of the stain. The proportion of claudin 18.2 positive cases varied between 24% and 83%. In works using a positivity threshold set at >40% or >70% of cells with membranous/cytoplasmic staining at 2+/3+ intensity, the average rate of positive cases was 50% or 30%, respectively (similar with clones 43-14A and EPR19202). Positivity of claudin 18.2 was associated with advanced stage, diffuse phenotype and PD-L1 and EBV positivity in some of the studies. Variability in criteria used to define claudin 18.2 positivity, as well as methodological differences, could explain the variation in the proportion of positive cases described, as well as the inconsistency of the association with clinical, molecular, and survival variables. The upcoming anticlaudin 18.2 therapy in advanced gastric cancer should prompt pathology laboratories to adjust their staining protocols and evaluation criteria in their series of patients, to further establish the association of claudin expression with clinical and molecular variables.

The 2018 ASCO/CAP guidelines for HER2 testing for breast cancer implemented the addition of immunohistochemistry (IHC) directed in situ hybridization (ISH) recount to resolve equivocal results. The implementation of an additional 2+ IHC-directed ISH recount adds additional complexity to the testing workflow for an unclear impact on HER2 results. A retrospective review of all equivocal ISH cases (groups 2, 3, and 4) that underwent 2+ IHC-directed ISH, since the 2018 guidelines, which were finalized as either amplified or not amplified, was performed. HER2 group number and final HER2 amplification status frequently changed after IHC guided ISH assessment, which was due to significant changes in HER2/CEP17 ratio and average HER2 signal number per cell. Equivocal groups 2, 3, and 4 samples with a result of HER2 amplified after 2+ IHC-directed ISH counts were closer to the threshold for amplification on the original ISH count, yet their counts also increased significantly after IHC-directed count in comparison to those samples, which were not amplified. Groups 2 and 4 ISH counts significantly increased after IHC directed ISH for HER2/CEP17 ratio and HER2 signal number per cell. This study represents the most extensive examination of efforts to resolve equivocal HER2 ISH results, highlighting a significant shift in therapeutic options after IHC-guided ISH for a subset of breast cancer patients.

Histologic grade is a key predictor for pseudomyxoma peritonei (PMP) of appendiceal origin that is used to guide clinical management. However, some tumors demonstrate disease behavior that deviates from their histologic grade. A recent study suggested that TP53, GNAS, and RAS mutation analysis could stratify tumors into distinct molecular groups with different prognosis. We investigated molecular alterations in 114 patients with PMP of appendiceal origin who were uniformly treated with cytoreductive surgery with intraperitoneal chemotherapy (CRS+IPCT). Tumors were separated into 4 groups based on their predominant genomic alteration: RAS-mut, GNAS-mut, TP53-mut, and triple-negative (RAS/GNAS/TP53-wildtype). The results were correlated with World Health Organization (WHO) grade, peritoneal carcinomatosis index (PCI), completeness of cytoreduction (CC) score, and overall survival (OS) from the time of CRS+IPCT using multivariate Cox proportional hazard analysis. Fifty percent of TP53-mut were WHO grade 3 compared with 38% triple-negative, 10% RAS-mut, and 7% GNAS-mut tumors (P<0.001). The TP53-mut group exhibited a significantly reduced OS compared with other groups (P<0.001). No significant OS difference was identified between RAS-mut, GNAS-mut, and triple-negative groups (P>0.05). In grade 3 PMP, TP53-mut was significantly associated with reduced OS (P=0.002). In the multivariate analysis for OS after CRS+IPCT, TP53-mut [hazard ratio (HR) 3.23, P=0.004] and WHO grade (grade 2 HR 2.73, P=0.03 and grade 3 HR 5.67, P<0.001) were the only independent predictors of survival. Our results suggest that, in addition to tumor grade, TP53 status may help to provide a more patient-centered approach in guiding therapy in PMP.

Melanoma antigen gene-A2 (MAGE-A2) is one of the most cancer-testis antigens overexpressed in a variety of malignancies. However, the expression of MAGE-A2 for clinical values in the pathophysiology of renal cell carcinoma (RCC) is unknown. For the first time, the present study was conducted to examine the expression and prognostic significance of MAGE-A2 expression in clear cell RCC (ccRCC). MAGE-A2 expression was assayed in 162 well-defined ccRCC samples using immunohistochemistry staining on tissue microarrays. The association between MAGE-A2 expression and clinic-pathologic features as well as survival outcomes were then performed. A significant and positive correlation was found between cytoplasmic expression of MAGE-A2 with tumor size (P=0.008), nucleolar grade (P =0.001), tumor stage (P =0.001), microvascular invasion (P=0.001), invasion to renal pelvis (P=0.032), renal sinus fat (P=0.004), and Gerota's fascia (P=0.028) as well as histologic tumor necrosis (P<0.0001). Increased expression of MAGE-A2 was observed to be associated with shorter progression-free survival (PFS) compared with patients with low expression of MAGE-A2 (P=0.032). Multivariate analysis revealed that tumor size and nucleolar grade are independent predictors of the PFS (P=0.054, P=0.032, respectively). Our results indicated that increased cytoplasmic expression of MAGE-A2 is associated with the malignant degree and progression of ccRCC. This data improved the significance of MAGE-A2 expression and will potentially allow using MAGE-A2 for the prognosis of the disease and immunotherapy in patients with ccRCC.

Follicular dendritic cell sarcoma (FDCS) is a rare neoplasm requiring a high index of suspicion, especially on small biopsies. Smooth muscle myosin heavy chain (SMMHC) is a common immunohistochemical (IHC) stain that has been reported to mark normal nodal follicular dendritic cells (FDCs). We hypothesize that SMMHC can be a sensitive marker for FDCS and aim to compare its performance with established markers of FDCS. The archive of a large academic center was searched for cases of FDCS. Clinical features, including age, sex, and site at diagnosis, were reviewed. A hematoxylin and eosin-stained slide was evaluated to assess for morphology and presence of hyaline vascular Castleman disease. The established FDC markers CD21, CD23, fascin, clusterin, and D2-40 were reviewed and compared with SMMHC for all cases. The staining pattern was classified as positive (strong or weak) or negative. Seven unique cases of nodal and extranodal FDCS were collected. SMMHC was positive in most cases (n=5) and performed similarly to established FDC markers, including clusterin, CD21, and CD23 (n=7 each), and fascin and D2-40 (n=4 each). SMMHC was also negative in all 14 examined cases among 5 common differential diagnoses. We demonstrate that the common IHC marker SMMHC has high specificity and similar sensitivity as established FDC markers in nodal and extranodal FDCS, and is useful in the evaluation of common neoplastic mimics.

PRAME is a cancer testis antigen whose expression is limited in normal tissues but is increased in cancers. Although there are studies revealing its oncogenic and immunogenic role, the relationship between PRAME expression and immunity in melanomas is not very clear. We aimed to reveal the relationship between PRAME expression and clinicopathologic parameters, immunologic markers, survival in melanomas. PRAME alteration data in TCGA SKCM data set was obtained from cBioPortal. Analyzes regarding clinicopathologic parameters were performed through cBioPortal and UALCAN, survival-related analyzes were performed through cBioPortal, GEPIA2. The correlation analyzes between PRAME expression and immune cell infiltration, immunity-related genes were performed in TIMER2.0, TISIDB, GEPIA2. PRAME protein-protein interaction network was constructed in STRING. The correlated genes with PRAME were listed in LinkedOmics, gene set enrichment and pathway analyses were performed through LinkInterpreter. In cases with low PRAME expression, there was a higher frequency of metastasis and p53 mutation, a more advanced tumor stage and a lower nodal stage. Strong relationship between PRAME expression and immune cell infiltration. A negative correlation was detected between expression of PRAME and many immunomodulatory genes (P<0.05). Positively correlated genes with PRAME expression were involved in metabolic pathways; negatively correlated genes were involved in pathways related to cell differentiation, immunologic processes. No significant relationship was found between PRAME expression and survival (P>0.05). Our findings reveal a strong interaction between PRAME expression and tumorigenicity, the immune system and shed light on further clinical studies including PRAME-targeted studies.

N6-methyladenosine (m6A) is the most abundant epigenetic RNA modification in eukaryotes and plays a role in various cancers in humans. This m6A modification is regulated by m6A writers, erasers, and readers. One of the m6A erasers is α-ketoglutarate-dependent dioxygenase homolog 5 (ALKBH5). Previous studies have suggested that ALKBH5 is involved in the pathogenesis of head and neck squamous cell carcinoma. However, the role of ALKBH5 in odontogenic lesions has never been investigated. This study aimed to examine ALKBH5 expression in dental follicles (DFs), dentigerous cysts (DCs), odontogenic keratocyst (OKC), and ameloblastoma (AM) using immunohistochemistry. Six cases of DF, 20 cases of DC and OKC, respectively, and 30 cases of AM were included. The expression patterns, percentage of ALKBH5-positive cells, staining intensities, and immunoreactive scores were examined. ALKBH5 was mainly expressed in the nuclei of the epithelial cells in odontogenic lesions. The percentage of ALKBH5-positive cells was significantly higher in OKC and AM samples compared with DF samples ( P < 0.01). The percentage of ALKBH5-positive cells was also higher in OKC and AM samples than in DC samples; however, these results did not show statistical significance ( P > 0.05). ALKBH5 cell staining intensities and immunoreactive scores were significantly greater in OKC and AM samples than in DF and DC samples ( P < 0.01). Our results suggested that ALKBH5 might play a role in the pathogenesis of odontogenic lesions. Further investigation is needed to elucidate the precise molecular mechanism of the role of ALKBH5 in these diseases.