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PubMed1990

Demonstration of oestrogen receptor in symptomatic breast carcinoma, using fine needle aspiration cytology.

Oestrogen receptor immunocytochemical assay (ER-ICA) was used to determine oestrogen receptor (ER) content of cells in fine needle aspirate (FNA) specimens from 88 breast carcinomas. In 49 of these the radioligand binding assay for oestradiol was available for comparison. The predictive value of ER-ICA staining for a positive radioligand binding assay (greater than 10 fmol/mg protein) was 95%. Although the predictive value of negative staining was only 66%, 34 out of 37 ER-ICA negative tumours had radioligand binding assays below 60 fmol/mg protein. ER-ICA staining showed a strong positive correlation with age of the patient, positivity being rare before the menopause. There was a weak inverse correlation with tumour grade but none with tumour size or lymph node status. The assessment of ER by immunocytochemistry using FNA cytology is a rapid technique, which may easily be repeated and provides a pre-operative assessment of ER status. It allows confirmation that tumour cells are present in the sample and an assessment of tumour heterogeneity.

Adult↗
PubMed2006

Characterization of ovarian surface epithelial cells from the hen: a unique model for ovarian cancer.

To further develop the hen as a model of ovarian adenocarcinoma, we have studied normal and neoplastic ovaries as well as cultured cells from the ovarian surface epithelium (OSE). We characterized the OSE layer of the hen for specific histologic markers and evaluated these markers on tumor tissue. We also isolated and characterized the epithelial cells that are the likely source of the ovarian tumors of the hen. The surface epithelium of normal ovaries demonstrated positive staining for cytokeratin, proliferating cell nuclear antigen (PCNA), progesterone receptor (PR), and negative staining for vimentin. Ovarian tumors demonstrated positive cytokeratin, PCNA, PR, and weak vimentin staining in the gland-like areas. Epithelial cell cultures were obtained by an explant method utilizing small and large yellow follicles. These cells were positive for cytokeratin and negative for vimentin on Days 1 and 3. By Day 10, cytokeratin protein expression was less for some cells, and vimentin expression was weakly present in some cells. Expression of PCNA was observed at Days 1 and 3, but was rarely seen in cells cultured for 10 days. Expression of PR was observed on Day 10 after 24-hr estrogen treatment. Epithelial cells grew slowly in culture, and were susceptible to trypsin or other dissociation treatments.

Adenocarcinoma↗
PubMed2001

Uroplakin as a marker for typing metastatic transitional cell carcinoma on fine-needle aspiration specimens.

BACKGROUND: Immunohistological markers specific for a single type of epithelium are rare. Recently, urothelium tissue-specific genes were cloned. The genes encoded a family of transmembrane proteins, uroplakins, that are expressed only in urothelial mucosa. Using uroplakin antibodies on paraffin-embedded tissue, a previous study demonstrated positive staining in 66% of metastatic transitional cell carcinoma (TCC) cases and negative staining in all other tumors (including breast, ovarian, lung, and gastrointestinal carcinomas) tested. The current study addresses the diagnostic value of uroplakins in conventional fine-needle aspiration (FNA) material in establishing a diagnosis of metastatic TCC. METHODS: Representative slides from 27 FNA cases of metastatic TCC and 52 non-TCC carcinomas were collected. The avidin-biotin-peroxidase method was utilized, using polyclonal antiuroplakin as the primary antibody on 95% ethanol-fixed, Papanicoloau-stained direct smears. RESULTS: Twenty-five of 27 metastatic TCC cases (93%) were found to stain positively for uroplakin with a superficial membrane/microluminal staining pattern. A few cells with diffuse membranous staining also were noted in 48% of the positive metastatic TCC cases. The superficial membrane/microluminal staining pattern was not observed in any of the non-TCC carcinomas. However, approximately 6% of these cases (3 of 52 cases) did show rare tumor cells with diffuse membranous staining. CONCLUSIONS: The application of uroplakin antibodies to 95% ethanol-fixed FNA direct smears has improved the sensitivity of the antibody for metastatic TCC while maintaining a specificity comparable to that of paraffin-embedded tissue. The authors believe that these antibodies have diagnostic potential in cytopathology in the evaluation of metastatic TCC.

Adult↗
PubMed2001

Prognostic significance of the expression of vascular endothelial growth factor (VEGF) and VEGF-C in gastric carcinoma.

BACKGROUND AND OBJECTIVES: Angiogenic factors play a major role in tumor growth and metastasis. The purpose of this study was to clarify the prognostic significance of the expression of vascular endothelial growth factor (VEGF) and VEGF-C in gastric carcinoma. METHODS: Formalin-fixed and paraffin embedded sections of tumor tissue were obtained from 76 patients who underwent curative gastrectomy for gastric carcinoma. Immunohistochemical staining for VEGF and VEGF-C was performed. RESULTS: VEGF and VEGF-C were positively expressed in 39 and 45% of the patients, respectively. No correlation existed between VEGF and VEGF-C expressions. VEGF expression was significantly correlated with venous invasion. VEGF-C expression was significantly correlated with lymphatic and venous invasion. Patients with positive staining for VEGF showed a significantly lower survival rate than VEGF negative patients. After subdivision, according to the combination of VEGF and VEGF-C expression, VEGF-C expression had a significant unfavorable impact on prognosis among patients with negative staining for VEGF. The expression of VEGF and/or VEGF-C was independent prognostic determinant by the multivariate survival analysis. CONCLUSIONS: The positive expression for VEGF and/or VEGF-C was an important prognostic determinant after curative gastrectomy for gastric carcinoma. VEGF-C may stimulate the tumor progression in the absence of VEGF.

Endothelial Growth Factors↗
PubMed1989

Non C-banding variants in some normal families might be homogeneously staining regions.

Three families are reported showing transmission of a previously described variant, which is not associated with any clinical abnormality. The variant involves additional material at the band 9p12, which shows homogeneous staining of intermediate density with GTL- and RBG-banding, and negative staining with CBG-banding. The region stains positively with Feulgen stain. In situ hybridization with total genomic human DNA, cloned alpha satellite, satellite III, and ribosomal DNA all show no hybridization to the 9p12 variant. Two members of one of the families show the largest 9p12 variant yet reported; two other carriers in this family have inherited a variant of decreased size. It is suggested that the 9p12 variants are homogeneously staining regions. Using the ISCN three-letter convention, this variant could be described as hsr(9)(p12).

Chromosome Banding↗
PubMed2004

A novel mutation of NPHS2 identified in a Chinese family.

Since the identification of the NPHS2 gene,which encodes podocin, several groups from European, Middle Eastern, and North American countries have reported NPHS2 mutations in families with steroid-resistant nephrotic syndrome (SRNS) or focal segmental glomerulo sclerosis (FSGS). Families with SRNS have also been reported in China with a population of more than1.3 billion. However, to our knowledge, there is no mutational analysis of the NPHS2 gene in familial SRNS orFSGS in China. We identified a novel mutation of NPHS2(467_468insT and 503G>A) in a Chinese family with autosomal recessive SRNS using polymerase chain re-action, denaturing high-performance liquid chromatography, and DNA sequencing techniques. The results demonstrate that there is also NPHS2 mutation in Chinese familial SRNS. Therefore, Chinese SRNS patients with a familial history of NS should also be screened for possible mutations of NPHS2. We also detected clearly decreased staining with a specific podocin C-terminal antibody(P35) and negative staining with a specific podocin N-terminal antibody (P21). These results were contrary to those predicted from the mutated sites. Further studies are needed to explore the mechanism and impact of the mutant gene on the expression and localization of the relevant protein.

Adult↗
PubMed1988

Detection of novel proteins associated with secondary amyloidosis and Alzheimer's disease by monoclonal antibody.

We have established a monoclonal antibody (MoAb) AM34 (IgG1) which was prepared by a hybridoma constructed from fusion between murine myeloma cells and murine splenocytes. Crude amyloid proteins which were used as immunogen, were extracted from the kidney of a patient with rheumatoid arthritis by the distilled water method. This antibody strongly reacted with all 8 cases of secondary amyloidosis, but did not react or very weakly reacted with 17 tissue sections of primary or myeloma-associated amyloidosis. Other amyloid tissues did not give any positive reaction. Interestingly, 6 brain tissues of Alzheimer's disease clearly showed positive staining with this antibody, whereas two apparently normal brain tissues exhibited negative staining. Senile plaque cores, neurofibrillary tangles (weakly stained) and cerebrovascular amyloid in Alzheimer's disease were stained. Absorption of the MoAb AM34 with the crude amyloid proteins abolished the immunoreactivity of the MoAb AM34 not only with the kidney tissue section of the secondary amyloidosis, but also with the above mentioned portions of the brain in the case of Alzheimer's disease. Therefore, these immunohistological data suggest that the MoAb AM34 recognizes common epitope which exists in amyloid deposits of both secondary amyloidosis and Alzheimer's disease. An inhibition test on the kidney section showed that the reactivity of MoAb AM34 was not at all inhibited by the pretreatment of the section with 10 times higher concentration of anti-human amyloid A (AA) MoAb KM268 which was prepared against synthetic peptides of AA protein, suggesting that MoAb AM34 might react with amyloid-related protein other than AA protein. In addition, MoAb KM268 did not react with any lesions in Alzheimer's disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Alzheimer Disease↗
PubMed1986

Immunolocalization of keratins in salivary gland pleomorphic adenoma using monoclonal antibodies.

Monoclonal antibodies to keratins (KL1 and PKK1) were tested on paraffin sections in forty cases of pleomorphic adenoma from salivary glands. Squamous cells in the epidermis were positive for KL1, except for the basal cells, which were positive for PKK1. In normal salivary glands, ductal cells were positive for KL1 and PKK1 keratins, whereas KL1 staining of the large excretory ducts was weaker than that of PKK1. Myoepithelial cells were positive only for KL1. In pleomorphic adenoma, the following reactions were noted: a positive staining for KL1 and PKK1 was present in the inner layer of cells within tubular and ductlike structures, a markedly positive staining for KL1 was present in squamous metaplastic cells, and a negative staining reaction with KL1 and PKK1 in spindle-shaped tumor cells was observed within the outer layer. Spindle-shaped or fibroblast-like cells in the stroma, probably myoepithelial in origin, showed an irregular staining expression for KL1 and PKK1.

Adenoma, Pleomorphic↗
PubMed1994

p53 alterations in gastric carcinoma: a study of 56 primary tumors and 204 nodal metastases.

We have looked for LOH, mutation, and expression of p53 in a series of 56 primary gastric carcinomas, using Southern blotting, constant denaturant gel electrophoresis (CDGE), direct sequencing, and immunohistochemistry. Two hundred-four lymph node metastases from 36 of these cases were also studied by immunohistochemistry. Loss of constitutional heterozygosity for the p53 locus was detected in five of 16 informative cases; in four of these cases there was a concurrent point mutation at the retained allele. Immunoreactivity for p53 product and mutation of p53 were observed in nine and 10 of the 56 tumors, respectively. There was no significant relationship between p53 immunoreactivity or mutation and pathologic features. The overall prevalence of p53 mutations, as detected by CDGE, was 18%. Direct sequencing confirmed p53 mutations (all G:C-A:T transitions) in seven cases, six of which were missense mutations; the remaining case was a silent mutation. In three of the cases with missense mutations, these occurred at CpG dinucleotides (codons 175, 273, and 282). Three cases with immunoreactivity for p53 product in the primary tumor also showed positive staining in the metastases. In two of these cases (with six and nine metastases, respectively) a positive staining was observed in all lymph node metastases, whereas in the remaining case only two of four nodal metastases were positively stained. In no single case was a positive staining observed in a metastasis where the primary tumor gave a negative staining result. Five of the six cases with p53 mutations and fresh material available for cell culture were successfully grown in vitro and all had abnormal karyotypes.

Adult↗
PubMed2004

Single brain metastases of carcinoid tumors.

Carcinoid tumors are one among the most uncommon source of metastatic lesion to the brain. Four cases of single brain metastases from carcinoid tumors operated upon and verified by both histology and immunohistochemical staining are reported. The site of the primary carcinoid tumor was the lung in two cases, ileum in one and the left colon in another. The location of the brain metastasis was supratentorial in two cases and cerebellar in two. A high vascular tumor with large blood channels was found at surgery. Immunohistochemical studies showed in all four cases positive staining for synaptophysin, neuron-specific enolase, chromogranine and cytocheratine and negative staining for S-100 and HMB-45. The postoperative survival time ranged from 5 to 18 months. The epidemiological, surgical and pathological features of brain metastases from carcinoid tumors are also discussed from the analysis of 44 well-documented cases reported in the literature.

Adult↗
PubMed2004

Soluble expression and characterization of a GFP-fused pea actin isoform (PEAc1).

A pea actin isoform PEAc1 with green fluorescent protein (GFP) fusion to its C-terminus and His-tag to its N-terminus, was expressed in prokaryotic cells in soluble form, and highly purified with Ni-Chelating Sepharose Fast Flow column. The purified fusion protein (PEAc1-GFP) efficiently inhibited DNase I activities before polymerization, and activated the myosin Mg-ATPase activities after polymerization. The PEAc1-GFP also polymerized into green fluorescent filamentous structures with a critical concentration of 0.75 uM. These filamentous structures were labeled by TRITC-phalloidin, a specific agent for staining actin microfilaments, and identified as having 9 nm diameters by negative staining. These results indicated that PEAc1 preserved the essential characteristics of actin even with His-tag and GFP fusion, suggesting a promising potential to use GFP fusion protein in obtaining soluble plant actin isoform to analyze its physical and biochemical properties in vitro. The PEAc1-GFP was also expressed in tobacco BY2 cells, which offers a new pathway for further studying its distribution and function in vivo.

Actins↗
PubMed1997

Prognostic importance of the nuclear proteins p53 and Rb in conjunction with DNA, nuclear morphometry and grading in endometrial carcinoma.

In a series of 227 cases of endometrial carcinomas in FIGO stages I-IV, treated during the years 1984-89, immunohistochemical staining for the protein products of the two tumor suppressor genes p53 and retinoblastoma (Rb) were evaluated as prognostic factors with regard to tumor stage, FIGO grade, nuclear grade, morphometric nuclear parameters, DNA ploidy and S-phase fraction. Long-term survival analyses were endpoints and the Cox multivariate technique was used to evaluate the prognostic factors. In 20% of the cases p53 was positive. This was a genuine high-risk group associated with primary advanced carcinoma, nonendometrioid histology, poorly differentiated tumors, severe nuclear atypia, DNA aneuploidy, primary persistent tumors, recurrent tumors and a poor long-term survival rate (37% 5-year survival). In patients dying of their disease, 54% of the tumors stained positive for p53, compared with only 10% of the tumors not killing their hosts. Positive p53 staining was more common in older women. A pathologic Rb status (negative staining) was recorded in 6% of the cases. The Rb factor had only a minor influence on long-term survival and was not significant in multivariate analyses. The p53 staining status was the second most important prognostic factor after the nuclear grade in Cox multivariate analyses, after correcting for stage and age. Immunohistochemical staining for p53 protein should be included among previous available and important prognostic factors in endometrial carcinoma.

Journal Article↗
PubMed2006

Nodular hyperplasia of Bartholin's gland.

AIMS: There has been very little mention of benign solid lesions of the Bartholin's gland (BG) in pathology and gynaecology textbooks, and very few cases have been reported in the literature. Among these lesions, the distinction between nodular hyperplasia (NH) and adenoma has not been well defined. We report ten cases of NH of the BG, describe their clinicopathological, immunohistochemical and ultrastructural findings, and review the literature. METHODS: We examined retrospectively all lesions involving BGs from our surgical pathology records from 1990 to 2004 with emphasis on NH. To separate NH from adenoma, we applied the criteria proposed by Koenig and Tavassoli. Special stains (PAS with and without prior digestion, Mayer's mucicarmine and Alcian blue with and without hyaluronidase) and immunohistochemistry (CAM5.2, AE1/AE3, HMWK, monoclonal CEA, EMA, ER, PR, ALA, SMA, Ki-67, p53 and polyclonal CEA) were performed on NHs. Two cases were examined ultrastructurally. RESULTS: Using specific criteria, ten cases (age range 23-45 years; mean 36.1) of NH were identified, two of which were diagnosed previously as adenoma, but re-classified as NH. Clinically, these lesions were described either as Bartholin's duct cysts (BDCs) or vulvar lumps. Grossly, NHs were solid, tan and unencapsulated, measuring 12.5-45.0 mm in maximum dimension (mean 23.8). Histologically, the NHs were composed of a proliferation of mucus-secreting acini with preservation of the normal duct-to-acinar relationship. Chronic inflammation and squamous metaplasia were present. Eight lesions focally involved the surgical margins. Intracytoplasmic and intra-luminal secretions were positive for PAS with and without digestion, Alcian blue with and without hyaluronidase and mucicarmine. All lesions showed positive staining for CAM5.2, AE1/AE3, HMWK, EMA, and polyclonal CEA. There was negative staining for Ki-67, ER, PR, ALA, p53 and monoclonal CEA. Periacinar myoepithelial cells stained for SMA. Ultrastructurally, the findings included abundant intracytoplasmic secretory granules, granulofibrillar bodies, prominent Golgi and ribosomes. Myoepithelial cells were identified. There was no tumour recurrence or malignant transformation in eight patients with clinical follow-up. CONCLUSION: NH of the BG is a rare lesion with benign behaviour. It is a distinct entity and can be separated histologically from an adenoma.

Adenoma↗
PubMed1987

Ultrastructural observations in cat scratch disease.

Because the causative bacterium of cat scratch disease has not been definitively cultured or fully characterized, the authors have studied its ultrastructure in lymph node biopsies from two patients using glutaraldehyde-fixed tissue. In both specimens, the organisms were invariably extracellular, forming small groups within bundles of collagen fibrils. Their appearance was similar in necrotic and viable regions of the nodes, although in the latter sites they could not be identified by light microscopic examination with the Warthin-Starry stain. The bacteria were pleomorphic rods, and, despite faint gram-negative staining, their walls were consistently thick and homogeneous.

Adolescent↗
PubMed2001

In-vitro evidence of autocrine secretion of vascular endothelial growth factor by endothelial cells from human placental blood vessels.

Vascular endothelial growth factor (VEGF), a highly specific mitogen for vascular endothelial cells, is involved in placental vascular growth and remodelling. The aim of this study was to investigate whether placental endothelial cells secrete VEGF in an autocrine manner and if this secretion is correlated with endothelial cell growth. Blood vessels, excised from the apical surface of three human placentae, were sectioned into 40 fragments per placenta and cultured in fibrin gel matrix for 27 days. Immunohistochemical detection of placental endothelial cells was performed by positive staining with anti-human factor VIII-associated antigen and negative staining with anti-human alpha-actin and desmin. To investigate the production and autocrine action of VEGF, VEGF concentrations in culture media were measured and the effect of an anti-VEGF neutralizing antibody on endothelial cell growth was observed. The results demonstrate that soluble VEGF is secreted by placental endothelial cells reaching a plateau from day 24 (68.74 +/- 7.52 pg/ml) to day 27 (67.20 +/- 6.28 pg/ml). Furthermore, VEGF concentrations in media collected on days 6, 12, 18, 21 and 27 of culture were found to be directly correlated to the sprouting parameter of endothelial cells, as calculated by image analysis on the same day ( P < 0.001, r (2) = 0.95 ). The use of 10 and 100 ng/ml of a neutralizing antibody against human VEGF suppressed cell proliferation, compared to that observed in the untreated controls, by 74.8 +/- 7.3 and 89.4 +/- 3.9% respectively. In conclusion, this study reports the first evidence of autocrine secretion of VEGF by human placental endothelial cells and demonstrates the involvement of VEGF in endothelial cell growth within a fibrin gel culture.

Autocrine Communication↗
PubMed1996

Pleomorphic large cell lymphomas of the mediastinum.

Nine cases of primary non-lymphoblastic, non-Hodgkin's large cell lymphomas of the mediastinum characterized by a highly pleomorphic histologic appearance are described. The patients, four women and five men, were aged 30 to 65 years. All patients presented with symptoms referable to their tumors, including cough, chest pain, dyspnea, pleural effusion, and superior vena cava syndrome. Clinical and pathologic staging in all patients showed that the bulk of the tumor was confined to the chest cavity at the time of initial diagnosis, with local infiltration into the neck, lung hilum, and surrounding mediastinal structures. Three different histological growth patterns were observed: one composed of a diffuse proliferation of pleomorphic, highly atypical cells with bizarre nuclear features that closely resembled a high grade sarcoma; another one composed of sheets of large, epithelial-appearing atypical cells suggestive of anaplastic carcinoma; and another pattern characterized by a pleomorphic proliferation of large lymphoid cells admixed with numerous scattered Reed-Sternberg-like cells reminiscent of the lymphocyte-depleted variant of Hodgkin's disease. Immunohistochemical studies on paraffin-embedded tissue sections in all cases showed positive staining of the tumor cells with CD20 and CD45 antibodies and negative staining with a large panel of markers, including broad-spectrum keratin, CAM 5.2, carcinoembryonic antigen, epithelial membrane antigen, vimentin, actin, desmin, HMB 45, S-100 protein, CD3, CD15, CD30, and CD45RO. Because of their location restricted to the anterior mediastinum, frequent lack of recognizable lymph node architecture, and bizarre cytologic features, the present group of lesions posed difficulties for diagnosis, their correct identification was achieved through the application of a panel of immunohistochemical markers. An awareness of these unusual histologic appearances of primary large cell lymphoma in the mediastinum and inclusion of a broad panel of lymphoid markers are therefore recommended for the evaluation of pleomorphic, undifferentiated malignant neoplasms of this anatomic region.

Adult↗
PubMed1997

Primary serous papillary adenocarcinoma of the vagina: a case report.

The first reported case of vaginal serous papillary adenocarcinoma (VSPA) in a 61-year-old woman is presented. The woman had a mass in the upper posterior vaginal wall that was 2.5 cm in maximal dimension and was treated with a radical hysterectomy with bilateral salpingo-oophorectomy, lymphadenectomy, and subtotal vaginectomy, followed by radiation therapy. The ovaries, fallopian tubes, cervix, endometrium, and peritoneum did not show primary or secondary neoplastic involvement. The patient died because of recurrent disease in the form of widespread peritoneal metastases 30 months postoperatively. Microscopically, the tumor was similar to serous papillary adenocarcinoma of the ovary (OSPA). Immunohistochemical studies showed positive staining for CA 125, CA19.9, DUPAN-2, and TAG-72, and negative staining for CEA. Cytogenetic analysis showed chromosome 6 abnormalities similar to those found in OSPA. These results suggest that VSPA is a clinically aggressive primary tumor sharing morphological and cytogenetic analogy with OSPA.

Adenocarcinoma, Papillary↗
PubMed1986

Staining of O-specific polysaccharide chains of lipopolysaccharides with ruthenium red.

S-form lipopolysaccharides (LPS) from Klebsiella strain LEN-1 (O3: K1-) and from Salmonella minnesota strain 1114 were positively stained with ruthenium red, whereas R-form LPS from Klebsiella strain LEN-111 (O3-: K1-) and Ra, Rb1, RcP+, Rd1P-, and Re LPS from the respective mutant strains of S. minnesota were not or only faintly stained by such treatment. From these results it was concluded that ruthenium red stains the O-specific polysaccharide chains of LPS. The appearance of stained preparations of S-form LPS suggested that the material responsible for this positive staining corresponded to the surface projections which were seen by the negative staining technique as attached to the ribbon-like structures and spherules of the LPS.

Carbohydrate Conformation↗