Expression of OLFM4 and Lysozyme During Necrotizing Enterocolitis and Volvulus in Newborns: a Comparative Observational Research Study

Background: In neonatal patients with necrotizing enterocolitis (NEC) and volvulus the inflammatory response is mediated by a plurality of different proteins. The proteins olfactomedin 4 (OLFM4) and lysozyme (LYZ) are part of the intestinal mucosal defense and especially OLFM4 has rarely been evaluated in neonatal gastrointestinal diseases. The aim of this study was to compare the expression levels of OLFM4 and lysozyme during NEC and volvulus in neonates. Methods: Intestinal tissues of patients with NEC and patients with volvulus were examined using immunohistochemical staining of OLFM4 and lysozyme of formalin-fixed and paraffin-embedded sections of resected tissue. Staining-positive tissues were semi-quantitatively scored from 0 (no staining), 1 (weak staining), 2 (moderate staining) to 3 (highly intense staining) by two individual investigators.Results: Both applied antibodies against OLFM4 showed different staining patterns with higher staining intensity of the antibody OLFM4 (D1E4M). OLFM4 (median score of the antibody OLFM4 (D1E4M): 3.0) and lysozyme (median score: 3.0) are highly expressed in intestinal and immune cells during NEC. The expression of OLFM4 and lysozyme in tissue with intestinal volvulus was also observable (median score of the antibody OLFM4 (D1E4M): 1.25) and median score of the antibody against LYZ: 2.0), but lower levels could be seen in comparison to tissue with NEC (p=0.033 and p=0.037, respectively).Conclusions: Both proteins, OLFM4 and lysozyme, may play a role in the pathogenesis of NEC and volvulus in neonatal patients, but the exact mechanisms of OLFM4 and lysozyme function and their role in immunological responses have not yet been resolved. These observations add new insights as basis for further large-scale population research.

Global Assessment of IRF8 as a Novel Cancer Biomarker

Interferon regulatory factor 8 (IRF8) is a member of the IRF family that is specific to the hematopoietic cell and is involved in regulating the development of human monocytic and dendritic-lineage cells, as well as B cells. Since its utility as a sensitive and specific monoblast marker in the context of acute monocytic leukemias has been recently demonstrated, we hypothesized that it may also be useful as a novel immunohistochemical marker in myeloid sarcomas and blastic plasmacytoid dendritic cell neoplasms (BPDCN) with respect to their differential diagnoses. In this retrospective study, we analyzed the IHC expression pattern of IRF8 in 385 patient samples across 30 types of cancers, referenced to their mRNA expression data available through TCGA. In addition, we assessed IRF8 in 35 myeloid sarcomas, and 13 BPDCNs. Twenty-four of 35 cases of myeloid sarcomas (68.5%) showed positivity for IRF8, with six cases (17.1%) demonstrating IRF8 expression in the absence of CD34 and MPO. All 13 of 13 BPDCNs (100%) showed strong uniform expression of IRF8 and was occasionally more definitive than CD123. IRF8 was negative in all desmoplastic small round cell tumors, Ewing sarcomas, synovial sarcomas, and undifferentiated pleomorphic sarcomas, as well as all epithelial malignancies tested except for 2 triple negative breast cancers that showed subset weak staining. In conclusion, IRF8 is a novel marker helpful in identifying extranodal hematopoietic tumors that can otherwise be difficult to diagnose given the broad differential diagnoses and frequent loss of more common lineage-defining markers.

Morphological, cytochemical and ultrastructural aspects of blood cells in freshwater stingray species in the middle Rio Negro basin of Amazonian Brazil

In the present work, we examined the morphology, dimensions, cytochemical staining reactions and ultrastructure of blood cells from three freshwater stingray species, Potamotrygon wallacei, Potamotrygon motoro and Paratrygon aiereba, living in the waters of the middle Rio Negro basin (Barcelos, Amazonas, Brazil). We identified erythrocytes, erythroblasts, thrombocytes and four types of leukocytes (basophils, heterophils, lymphocytes and monocytes) in the blood of these stingray species. In all the freshwater stingray species studied, the shapes and dimensions of these cells were similar to those of marine elasmobranchs. Positive PAS staining occurred in heterophils and thrombocytes, and weak staining occurred in lymphocytes and monocytes, while metachromasia only occurred in basophils. Positive Sudan Black B staining was observed in thrombocytes and lymphocytes, and weak staining occurred in heterophils. Basophils and heterophils were the only cells with positive bromophenol blue staining, while no peroxidase staining was observed in any of the four leukocyte types. This is the first study to establish the dimensions and cytochemical staining profiles of blood cells in Amazonian stingray species. Because these elasmobranch species are exported as ornamental fish to countries worldwide, this study can contribute to establishing standards for blood constituents that may be helpful in assessing the health and welfare of these fish in artificial systems.

Efficiency of neutral honey as a tissue fixative in histopathology

In the routine laboratory, 10% neutral buffered formalin (NBF) is the fixative of choice. However, formalin is a human carcinogen. To the best of our knowledge, neutral honey, not natural or artificial honey, has not been tested to fix histological tissues. This study aimed to examine the efficiency of neutral buffered honey and other types of honey fixatives to fix histological tissues. The most two natural common Omani honey were used as fixatives, namely Sumar and date. We tested samples of rat liver, kidney, and stomach. Nine types of fixatives were used. All tissues were treated equally. The evaluation was performed blindly by three senior biomedical scientists who work in a histopathology laboratory. Hematoxylin and eosin showed adequate staining in all groups when compared to 10% NBF. The intensity and specificity of Jones Methenamine silver stain in 10% Sumer and Date honey and 10% alcoholic Sumer honey showed similar findings of 10% NBF. The specificity and intensity of all groups for Periodic acid–Schiff were comparable with 10% neutral buffered formalin accepts for 10% Sumer honey and 10% Alcoholic Date honey. However, all honey groups showed weak staining for the reticulin fibers using Gordon and Sweets method. Vimentin showed comparable findings with 10% NBF as there were no significant differences. The findings of this study are promising. Further in depth research on honey as a possible safe substitute fixative for formalin should be conducted.

Mesothelin Expression in Human Tumors: A Tissue Microarray Study on 12,679 Tumors

Mesothelin (MSLN) represents an attractive molecule for targeted cancer therapies. To identify tumors that might benefit from such therapies, tissue microarrays including 15,050 tumors from 122 different tumor types and 76 healthy organs were analyzed for MSLN expression by immunohistochemistry. Sixty-six (54%) tumor types showed at least occasional weak staining, including 50 (41%) tumor types with at least one strongly positive sample. Highest prevalence of MSLN positivity had ovarian carcinomas (serous 97%, clear cell 83%, endometrioid 77%, mucinous 71%, carcinosarcoma 65%), pancreatic adenocarcinoma (ductal 75%, ampullary 81%), endometrial carcinomas (clear cell 71%, serous 57%, carcinosarcoma 50%, endometrioid 45%), malignant mesothelioma (69%), and adenocarcinoma of the lung (55%). MSLN was rare in cancers of the breast (7% of 1138), kidney (7% of 807), thyroid gland (1% of 638), soft tissues (0.3% of 931), and prostate (0 of 481). High expression was linked to advanced pathological tumor (pT) stage (p < 0.0001) and metastasis (p < 0.0001) in 1619 colorectal adenocarcinomas, but unrelated to parameters of malignancy in 1072 breast-, 386 ovarian-, 174 lung-, 757 kidney-, 171 endometrial-, 373 gastric-, and 925 bladder carcinomas. In summary, numerous important cancer types with high-level MSLN expression might benefit from future anti-MSLN therapies, but MSLN’s prognostic relevance appears to be limited.

In the porcine placenta, aromatase (CYP19) is specifically expressed in trough-like structures of the trophoblast at the basis and flanks of chorionic folds

Aromatase was localized in the porcine placenta by immunohistochemistry during the first peak of maternal estrogen concentrations (D25; n=3), their nadir around midgestation (D50; n=3) and their second increase in late gestation (D110; n=3). On D25, aromatase was highly expressed throughout the trophoblast. On D50, its expression was restricted to the trophoblast lining the trough-like fossal regions between the bases of chorionic folds. However, immunostaining was detected only in a minor proportion of these locations, with staining intensity being generally only weak to moderate. On D110, distinct to intense immunostaining was found in virtually all trophoblast fossal regions and in similar structures at the flanks of chorionic folds adjacent to the free margins of secondary and tertiary endometrial folds. A weak staining of questionable specificity was occasionally observed in endometrial glands. In other cell types of the utero-placental compartment, aromatase was undetectable. The results suggest that in pigs placental estrogens could be involved in the formation of a more complex geometry of the feto-maternal interface as pregnancy progresses.

No correlation between Galectin-3 expression and clinicopathological features of follicular thyroid carcinoma minimally invasive: study in single institution

Background. Galectin-3 has been suggested to involve in invasion and aggressive behaviour of several cancer. The aim of this study is to evaluate the immunoreactivity of Galectin-3 in follicular thyroid carcinoma (FTC) in an attempt to investigate its association with clinicopathology of FTC. Method. This study included 46 selected paraffin embedded tissue blocks from surgically resected follicular thyroid carcinoma minimally invasive, consists of 23 cases of FTC capsular invasion only and 23 cases of FTC encapsulated angioinvasive. Immunohistochemistry staining for Galectin-3 were performed on all cases. Galectin-3 protein expression was observed in the cytoplasm and the nucleus of examined tissues. Result. Forty-three (93.5%) samples had strong or moderate staining and 3 (6.5%) tumours had negative or weak staining. Positive immunoreactivity of Galectin-3 was found in 18/23 (78.3%) cases of FTC capsular invasion only and 20/23 (86.9%) cases of FTC encapsulated angioinvasive. The galectin-3 did not show association with the sex (p=0.345), age (p=0.200), and tumour size (p=0.767). There was no significant difference of Galectin-3 immunohistochemical expression between FTC capsular invasion only and FTC encapsulated angioinvasive (p= 0.699). Conclusion. No differentiation of sex, age, tumour size, and immunohistochemical expression of galectin-3 in capsular invasion only and encapsulated angioinvasive of minimally invasive FTC.

Positivity for SATB2 distinguishes Islet1 positive rectal neuroendocrine tumours from pancreaticoduodenal neuroendocrine tumours

AimsDetermining the site of origin of a metastatic neuroendocrine tumour (NET) can be challenging and has important prognostic and therapeutic implications. An immunohistochemical (IHC) panel consisting of TTF1, CDX2, PAX8/PAX6 and Islet1 is often employed. However, there can be a significant IHC overlap among different primary sites. Herein, we sought to determine the utility of including Special AT-rich sequence binding protein-2 (SATB2) in the IHC panel that is used for determining the site of origin of a metastatic NET.MethodsParaffin tissue microarrays consisting of 137 primary NETs (26 lung, 22 jejunoileal, 8 appendix, 5 stomach, 4 duodenum, 17 rectum and 55 pancreas) were stained for SATB2, in addition to the well-described lineage-associated markers, such as TTF1, CDX2, PAX6 and Islet1. Additionally, a tissue microarray consisting of 21 metastatic NETs (1 lung, 1 stomach, 8 jejunoileal and 11 pancreas) was stained for TTF1, CDX2, SATB2 and Islet1. The results were recorded as no staining, weak staining and moderate to strong staining.ResultsAll appendiceal NETs and majority (88%) of the rectal NETs were positive for SATB2. All primary foregut NETs (stomach, pancreas, duodenum and lung) were negative for SATB2, except for one pulmonary NET with weak staining. However, among the metastatic tumours, 5 of 11 pancreatic NETs, 1 stomach NET, 1 lung NET and 2 of 8 jejunoileal NETs showed weak staining. Receiver operating characteristic analysis incorporating sensitivity and specificity data of IHC panel, considering moderate to strong staining as truly positive cases, showed that inclusion of SATB2 to the previously described NET IHC panel outperformed the panel without SATB2, raising the specificity for pancreaticoduodenal NETs from 81.2% to 100%, with a positive predictive value (PPV) of 100% and negative predictive value (NPV) of 82.22% (p<0.0001); for appendiceal NETs the specificity changed from 99.1% to 98.5% and sensitivity increased from 11.8% to 80%, with a PPV and NPV of 66.67% and 99.26%, respectively (p<0.0001); and for rectal NETs the specificity increased from 97.6% to 99.3% and sensitivity raised from 7.1% to 66.7%, with a PPV and NPV of 80% and 98.53%, respectively (p<0.0001).ConclusionsSATB2 stain is useful in differentiatingIslet1/PAX6 positive pancreatic and rectal NETs, as rectal NETs are typically moderately to strongly positive for SATB2 and pancreatic NETs are usually negative or weakly positive for SATB2. Moderate to strong staining for SATB2 is suggestive of an appendiceal or a rectal primary. SATB2 may complement the panel of CDX2, TTF1 and Islet1 in determining the site of origin of an NET in a metastatic setting.

Immunohistochemical Study of Glucose Transporter GLUT-5 in Duodenal Epithelium in Norm and in T-2 Mycotoxicosis

Although patterns of glucose transporter expression and notes about diseases leading to adaptive changes in intestinal fructose transport have been well-characterized, the connection between infection and fructose transportation has been lightly investigated. Up to now only few studies on GLUT-5 expression and function under pathological conditions in bird intestines have been carried out. The aim of our current research was to immunolocalize GLUT-5 in chicken duodenal epithelium in norm and during T-2 mycotoxicosis. Material from chicken (Gallus gallus domesticus) duodenum was collected from twelve seven-day-old female broilers, divided into control group and broilers with T-2 mycotoxicosis. The material was fixed with 10% formalin and thereafter embedded into paraffin; slices 7 μm in thickness were cut, followed by immunohistochemical staining, according to the manufacturers guidelines (IHC kit, Abcam, UK) using polyclonal primary antibody Rabbit anti-GLUT-5. Our study revealed the strong expression of GLUT-5 in the apical parts of the duodenal epithelial cells in the control group chickens and weak staining for GLUT-5 in the intestinal epithelium in the T-2 mycotoxicosis group. Our results confirmed decreased the expression of GLUT-5 in the duodenal epithelium during T-2 mycotoxicosis.

Expression of nectin-4 in bladder cancer with variant histology.

546 Background: The antibody-drug conjugate enfortumab vedotin is poised to change the bladder cancer (BC) treatment landscape by targeting Nectin-4, near ubiquitously expressed in urothelial cancer (UC). Less is known about this and other targets in BC with pure or mixed variant histology (VH). Methods: Immunohistochemistry (IHC) was performed on a Ventana Discovery Autostainer (Roche Diagnostics) using an ultraView DAB detection kit (Roche Diagnostics) and a Nectin-4 polyclonal antibody (1:100 dilution; Abcam, Cambridge, UK). The intensity and extent of Nectin-4 expression was determined by the histochemical scoring (H-score) used in preclinical testing, defined as the sum of the products of the staining intensity (score of 0–3) x % of cells (0–100) stained at a given intensity. Specimens were assessed by H score as: negative (0–14), weak (15–99), moderate (100–199), and strong (200–300). Results: Forty UC and VH BC were evaluated for Nectin-4 expression by IHC: 15 small cell (SCBC) (8 pure SCBC, 6 mixed SCBC/UC, 1 SCBC/CIS), 8 carcinosarcomas (CS) (7 pure CS, 1 HGUC/sarcomatoid features), and 17 pure HGUCs. Normal urothelium and stroma were negative. Eight of 8 (100%) pure SCBC were negative for Nectin-4. Six of 7 (85.3%) mixed SCBC+HGUC/CIS had weak staining and 1/7 (14.7%) had moderate staining in the urothelial components (comp) while 7/7 (100%) of the SCBC comp were negative. Seven of 7 (100%) pure CS were negative and 1/1 (100%) mixed CS+HGUC showed weak staining in the HGUC comp while the sarcomatoid comp was negative. Expression in UC was: 1/17 (5.9%) strong, 3/17 (17.6%) moderate, 10/17 (58.8%) weak, and 3/17 (17.6%) negative. Gene expression profiling confirmed Nectin-4 was downregulated in VH compared to UC samples, as was ERBB2 and Trop2. Conclusions: There is heterogeneity of expression of Nectin-4 and other targets in BC with VH compared to UC. This may have therapeutic implications, and highlights need for additional research in VH.[Table: see text]