Hepatic sonic hedgehog protein expression measured by computer assisted morphometry significantly correlates with features of non-alcoholic steatohepatitis.

Background: Hepatic expression of Sonic Hedgehog (SHH) is associated with Non-alcoholic fatty liver disease (NAFLD) and development of Non-alcoholic steatohepatitis (NASH). Hepatic SHH detection increases with the diagnosis of NASH. This pilot study was designed to confirm that staining for SHH is useful in NASH diagnosis and determine whether quantification of staining by computer assisted morphometry (CAM) can be used to assess severity of ballooning degeneration.

Cells with minimal expression of the JAK/STAT pathway related proteins STAT5a and the prolactin receptor: evidence of an alternate prolactin receptor isoform in breast disease.

Usually, wherever breast STAT5a is present, PRLR is reduced; without STAT5a PRLR becomes abundant. Five breast lesions essentially lacking both were tested immunohistochemically for PRLR isoforms. The intermediate isoform was essentially only detected in these lesions.

The avidin-biotin complex (ABC) method and other avidin-biotin binding methods.

Immunoenzyme methods can be enhanced by the use of the high affinity molecules, avidin and biotin. The binding of avidin to biotin is almost irreversible. By labeling a detection enzyme such as horseradish peroxidase with biotin, and a secondary antibody (reactive against the antigen detecting primary antibody) with biotin as well, these two compounds can then be linked irreversibly with avidin.

The peroxidase-antiperoxidase (PAP) method and other all-immunologic detection methods.

Immunoenzyme procedures take on many forms, including, simply, antibody coupled to enzyme. These direct techniques require the labeling of all the primary antibodies and can produce more background. A more economical method uses a secondary antibody or one that has the primary antibody as its antigen.

Overview of antigen detection through enzymatic activity.

The identification of antigenic substances with antibodies can only occur through the use of a reporter molecule. One way of doing this is through the use of enzymes. Enzymes act upon a substrate and that substrate, or a molecule affected by that substrate, in turn becomes detectable by a variety of methods.

Processing of tissue specimens.

In order to test tissue specimens with antibody, they first have to be preserved in fixative, embedded in paraffin, and sectioned very thinly onto glass microscope slides. Any piece of tissue, immediately after excision, must be placed into an adequate volume of fixative. Fixatives vary, but the standard one is 10% buffered formalin.

Processing of tissue culture cells.

Live cells are often studied, in vitro, bathed in nutrient growth media. It is sometimes necessary to study individual compounds produced by these cells and antibodies work well for this purpose. These cells must first be concentrated and fixed before testing.

Processing of cytological specimens.

Individual cells often need to be examined with antibodies apart from the surrounding tissue. They may be cells in fluid, cells encased in mucus from a swab, or cells directly extracted from a piece of tissue. Cells can be viewed on a glass slide as cell smears produced from a cell enriched source, introduced as a touch preparation from a piece of wet tissue, concentrated on a slide by the use of a cytocentrifuge, or applied directly to a slide from a solid medium such as a cotton swab.

Preparation of frozen sections for analysis.

The analysis of frozen tissue by antibodies can be accomplished by the quick freezing of a small tissue sample in liquid nitrogen. Super-cooled isopentane can also be used to further the preservation process. Freezing preserves the available proteins in a near-native state for their identification by antibodies raised against naturally folded proteins.

Reversed Expression of the JAK/STAT Pathway Related Proteins Prolactin Receptor and STAT5a in Normal and Abnormal Breast Epithelial Cells.

The JAK/STAT pathway is important for cellular metabolism. One component, STAT5a, is activated in the breast upon prolactin to prolactin receptor (PRLR) binding facilitating the transcription of genes involved in lobule development. STAT5a was previously found to be expressed in most normal breast epithelial cells but not in many in situ or invasive carcinomas except secretory carcinomas which retain STAT5a expression.

Diagnostic utility of WT1 immunostaining in ovarian sertoli cell tumor.

WT1, the Wilms tumor gene product, can be expressed in various tumors from different anatomic sites, including some types of ovarian tumors. Regarding the latter, most studies have focused on surface epithelial-stromal tumors in which serous carcinomas are usually positive and endometrioid carcinomas are negative. Very few studies have specifically investigated this marker in ovarian sex cord-stromal tumors; however, limited data in the literature suggest that WT1 may be frequently expressed in sex cord-stromal tumors.

Comparative analysis of alternative and traditional immunohistochemical markers for the distinction of ovarian sertoli cell tumor from endometrioid tumors and carcinoid tumor: A study of 160 cases.

The main neoplasms in the differential diagnosis for primary ovarian tumors with a tubule-rich pattern are pure Sertoli cell tumor, endometrioid tumors (including borderline tumor, well-differentiated carcinoma, and the sertoliform variant of endometrioid carcinoma), and carcinoid tumor. Because traditional immunohistochemical markers [pan-cytokeratin (pan-CK), low molecular weight cytokeratin (CK8/18), epithelial membrane antigen (EMA), inhibin, calretinin, CD99, chromogranin, and synaptophysin] can occasionally have diagnostic limitations, the goal of this study was to determine whether or not any alternative markers [cytokeratin 7 (CK7), estrogen receptor (ER), progesterone receptor (PR), CD10, and CD56] have better diagnostic utility when compared with traditional markers for this differential diagnosis. Immunohistochemical stains for alternative, as well as traditional, markers were performed on the following primary ovarian tumors: pure Sertoli cell tumor (n = 40), endometrioid borderline tumor (n = 38), sertoliform endometrioid carcinoma (n = 13), well-differentiated endometrioid carcinoma (n = 27), and carcinoid tumor (n = 42).

Immunohistochemical analysis of sox9 in ovarian Sertoli cell tumors and other tumors in the differential diagnosis.

The distinction of ovarian Sertoli cell tumor from other tumors in the histological differential diagnosis, particularly endometrioid carcinoma and carcinoid tumor, may be difficult. Many immunohistochemical markers have been studied for this differential diagnosis, but currently available markers are neither 100% sensitive nor specific. Sox9 is a transcription factor involved in Sertoli cell differentiation in the testis.

STAT 5a expression in the breast is maintained in secretory carcinoma, in contrast to other histologic types.

The 7 signal transducer and activator of transcription (STAT) molecules are responsible for the transcription of a variety of regulatory and differentiation proteins. STAT 5a is activated through a variety of mechanisms; in the breast, this is predominantly through binding of prolactin to its receptor. Previously, we showed that STAT 5a expression is decreased in atypical and malignant breast ductal epithelial cells.

Antibodies targeting p63 react specifically in the cytoplasm of breast epithelial cells exhibiting secretory differentiation.

Aims: The nuclear detection of p63 in myoepithelial cells of the breast has been useful in identifying possibly invasive carcinomas. While examining myoepithelial cells for p63 a very strong cytoplasmic reaction product was noted in secretory cells. The aim was to determine whether this reaction is specific for p63 and indicative of all breast secretory cells.

STAT 5a expression in various lesions of the breast.

The seven signal transducer and activator of transcription (STAT) molecules are effectors of hormonal or cytokine stimulation through receptors. STAT 5a, isolated from prolactin-stimulated mammary cells, contributes to normal proliferation and is essential for mammary gland differentiation. Using a monoclonal antibody, we tested 100 formalin-fixed, paraffin-embedded breast tissues representing everything from simple hyperplasia to invasive carcinoma for the expression of STAT 5a in comparison to normal breast epithelial cells.

Tubulolobular carcinoma of the breast: an analysis of 27 cases of a tumor with a hybrid morphology and immunoprofile.

Tubulolobular carcinoma (TLC) is a rare subtype of mammary carcinoma that has eluded precise classification, exhibiting features of both ductal and lobular differentiation. The clinicopathologic features of 27 cases of TLC were analyzed by both hematoxylin and eosin and immunohistochemical stains for E-cadherin and 34betaE12 (high molecular weight cytokeratin). Five cases of both pure tubular and classic lobular carcinoma were included as controls.

Morphologically similar epithelial and stromal cells in primary bilateral breast tumors display different genetic profiles: implications for treatment.

The morphologic features of primary bilateral breast carcinoma have been well elucidated, but it is not known whether tumors at two sides share a common genetic profile and undergo the same clinical course. To address this issue, morphologically comparable epithelial and stromal cells in 18 paired primary bilateral breast tumors were microdissected and subjected to comparisons for the frequency and pattern of loss of heterozygosity (LOH) and microsatellite instability (MI), as well as the profiles of comparative genomic hybridization. Of 18 paired bilateral epithelial samples assessed with 10 DNA markers at five chromosomes, 78 altered loci were found; of these, 23 (29.

The T cell receptor gamma chain alternate reading frame protein (TARP), a prostate-specific protein localized in mitochondria.

We previously showed that mRNA encoding TARP (T cell receptor gamma chain alternate reading frame protein) is exclusively expressed in the prostate in males and is up-regulated by androgen in LNCaP cells, an androgen-sensitive prostate cancer cell line. We have now developed an anti-TARP monoclonal antibody named TP1, and show that TARP protein is up-regulated by androgen in both LNCaP and MDA-PCa-2b cells. We used TP1 to determine the subcellular localization of TARP by Western blotting following subcellular fractionation and immunocytochemistry.

Assessment of lesions coexisting with various grades of ductal intraepithelial neoplasia of the breast.

Ductal intraepithelial neoplasia (DIN) is descriptive of in situ breast lesions from usual ductal hyperplasia (UDH) to advanced ductal carcinoma in situ (DCIS). A total of 2628 cases of DIN diagnosed at the Armed Forces Institute of Pathology were separated based on their grade. These were assessed for the presence of invasive carcinoma (ductal or lobular) and lobular intraepithelial neoplasia (LIN) grades 1-3.

Cell clusters overlying focally disrupted mammary myoepithelial cell layers and adjacent cells within the same duct display different immunohistochemical and genetic features: implications for tumor progression and invasion.

Introduction: Our previous studies detected focal disruptions in myoepithelial cell layers of several ducts with carcinoma in situ. The cell cluster overlying each of the myoepithelial disruptions showed a marked reduction in or a total loss of immunoreactivity for the estrogen receptor (ER). This is in contrast to the adjacent cells within the same duct, which were strongly immunoreactive for the ER.

Cytokeratin immunoreactivity in lobular intraepithelial neoplasia.

Eighteen commercially available antibodies reactive against different cytokeratin proteins were tested on classic examples of lobular intraepithelial neoplasia (LIN) and of ductal intraepithelial neoplasia (DIN) of the breast. About 90% of higher-grade DIN (AIDH and DCIS) show no or substantially diminished reaction with clone 34betaE12 (specified as reactive against keratins 1, 5, 10, and 14 as determined by the manufacturer), while the cells of LIN were found to express the antigen reactive with this antibody. To determine which of these four keratins are present in the cells of LIN, antibodies reactive against these individual four keratins were tested.

A subset of morphologically distinct mammary myoepithelial cells lacks corresponding immunophenotypic markers.

Introduction: Immunostaining for smooth muscle actin (SMA) is commonly used to elucidate mammary myoepithelial (ME) cells, whose presence or absence is a reliable criterion for differentiating in situ and invasive carcinomas. However, some morphologically distinct ME cells fail to stain for SMA. This study intended to assess whether these SMA-negative cells also lack the expression of other ME cell markers.