Immunoreactivity In Stromal Cells Research Articles

Immuno Localization of Estrogen Receptor (ERα) and Progesterone Receptor (PR) in Uterus of Buffalo during Follicular and Luteal Phases of Estrous Cycle

The tissue distribution of estrogen receptor alpha (ERα) and progesterone receptor (PR) was examined using immunohistochemical technique. Image analysis was done to quantify the immune reactivity. The ERα and PR was localized in luminal epithelium, glandular epithelium, stromal cells, endothelial cells and myometrium and few cells in perimetrium. The immuno staining was observed in the nuclei of cells, however, faint cytoplasmic staining for PR was also observed. Variations were seen in the different tissue compartments of the uterus and during the different phases of the estrous cycle. Significantly higher number of ERα positive cells was observed in lamina epithelialis as compared to stromal cells and smooth muscle cells in myometrium. Significantly higher percentage of ERα positive cells was observed in the lamina epithelialis and lining epithelium of endometrial glands during follicular phase as compared to the luteal phases of estrous cycle (P < 0.05). Higher number of PR positive cells was observed in lamina epithelialis as compared to stromal cells and smooth muscle cells in myometrium (P < 0.05). Higher percentage of PR positive cells was observed in the lamina epithelialis during follicular phase as compared to the luteal phases of estrous cycle (P < 0.05). There was no significant difference in the immuno reactivity in stromal cells, lining epithelium of endometrial glands and smooth muscle cells of myometrium during the phases of estrous cycle. The study concluded that ERα and PR expressions were higher during follicular phase as compared to the luteal phase.

Asynchronous glands in secretory pattern endometrium: clinical associations and immunohistological changes.

The significance and pathogenesis of irregular or asynchronous maturation within endometrial glands remains uncertain. The aim of this study was to investigate differences in epithelial hormone receptor immunoreactivity and stromal cell calretinin, CD34 and p16 expression in morphologically normal secretory endometrium and in asynchronous (non-secretory) endometrial glands (AEGs). Nineteen consecutive endometrial specimens showing AEGs were examined. The mean age of the patients was 42.8years, and the most common presenting symptom was menorrhagia. Immunohistological expression of oestrogen receptor (ER) α, of ERβ and of progesterone receptor (PR) were compared in normal secretory glands and in AEGs. Stromal cell expression of calretinin, CD34 and p16 was also investigated. In contrast to normal secretory glands, the epithelial cells lining AEGs were usually ERα/PR-positive and showed significantly increased ERβ expression. Altered calretinin and CD34 expression within functional layer stromal cells was seen in five and two cases, respectively, but there were no differences in stromal cell immunoreactivity around AEGs. The most common clinical symptom associated with AEGs in this study was menorrhagia. Aberrant hormone receptor expression in AEGs suggests a localized, possibly clonal, defect in epithelial maturation. There were no immunophenotypic changes to suggest that AEGs are related to a primary endometrial stromal deficiency.

Immunohistochemical Expression of RAGE and Its Ligand (S100A9) in Cervical Lesions

Altered expressions of receptor for advanced glycation end-products (RAGE) and its ligand (S100A9) are observed in many cancers and play a key role in inflammation-associated cancer. In our previous study, by two-dimensional gel electrophoresis followed by mass spectrometry, the expression of S100A9 protein was found to increase in squamous cervical cancer compared with adjacent normal cervical tissues. Therefore, in the present study we observed the expressions of S100A9 and RAGE in 30 chronic cervicitis, 50 cervical intraepithelial neoplasia (CIN), and 40 squamous cervical cancer (SCC) using immunohistochemical analysis and analyzed the differential expression and possible role of S100A9 and RAGE in cancer development. Immunohistochemical findings were as follows: the expressions of S100A9 and RAGE were demonstrated in chronic cervicitis, CIN, and SCC. Moreover, their expressions were gradually increasing as the tumor progressed. In SCC, the staining scores of S100A9 and RAGE were significantly higher in well-differentiated tumors compared to moderately and poorly differentiated tumors. The expression of S100A9 in epithelial cells exhibited a positive correlation to RAGE expression in chronic cervicitis, CIN, and SCC. There were no significant difference of S100A9 immunoreactivity in stromal cells among chronic cervicitis, CIN, and SCC. Moreover, there was no correlation between S100A9 immunoreactivity in stromal cells of SCC and clinicopathological parameters. Finally, double immunohistochemistry illustrated that RAGE and S100A9 co-express in SCC. In conclusion, RAGE binds its ligand (S100A9), which plays an important role in the development of SCC. In addition, the expressions of S100A9 and RAGE in SCC tumor cells were closely associated with histological differentiation.

Overexpression of SPARC protein contrasts with its transcriptional silencing by aberrant hypermethylation of SPARC CpG-rich region in endometrial carcinoma

Secreted protein acidic and rich in cysteine (SPARC) is a secreted matricellular glycoprotein involved in crucial processes that occur during cancer. This study explored the occurrence of deregulated expression of SPARC in endometrial carcinomas, since it has been associated with the progression of other tumor types. We analyzed the expression of SPARC in endometrial carcinomas by TaqMan, Western blotting and immunohistochemistry. The CpG island methylation status of SPARC was evaluated by bisulfite sequencing method. A significant down-regulation of SPARC mRNA expression (p<0.001) was observed in endometrial tumor tissues, regardless of their microsatellite instability status (MSI). The down-regulation can be accounted for by aberrant hypermethylation of its CpG-rich region, since we demonstrate that SPARC is a frequent target of this epigenetic event in this pathology. Although, differential expression of SPARC is already known in other cancer types, we report that down-regulation of the SPARC gene in endometrial tumors, formed by at least 80% of epithelial tumor cells, contrasts with a frequent overexpression of SPARC protein, with strong immunoreactivity in stromal cells. These results indicate a cell type specific expression of SPARC in endometrial carcinomas. Accumulation of SPARC protein in most tumors compared to normal tissues (p<0.025), suggests an important role in the carcinogenesis of endometrial tumors. SPARC overexpression can be a useful molecular tool that may contribute to the diagnosis of this disease.

Immunoprofile of Endocervical and Endometrial Stromal Cells and Its Potential Application in Localization of Tumor Involvement

To evaluate and compare the immunophenotype of endocervical and endometrial stromal cells and to asses its potential application in tumor localization. Paraffin sections of benign endocervix (n = 24), benign endometrium (n = 33), endocervical adenocarcinoma (n = 9), endometrial carcinoma (n = 13), and endometrial hyperplasia (n = 16) were stained with antibodies to CD10, Wilms Tumor-1, CD34, smooth muscle actin, and factor XIIIa by immunohistochemistry. In 16 cases, lower uterine segment was also available. Immunoreactivity of stromal cells was recorded as positive (>/=50% staining), focally positive (>/=5%-<50%) or negative (<5%). Endocervical stromal cells (ECSC) in either benign or malignant cervical epithelial lesions were predominantly CD34/CD10 (CD34 dominant immunophenotype). Endometrial stromal cells (EMSCs) in either benign or malignant epithelial lesions were primarily CD34/CD10 (CD10 dominant immunophenotype). Expression of Wilms Tumor-1 was decreased in EMSC of the EMCA when compared to their counterpart in endometrial hyperplasia. There was no differential expression of smooth muscle actin and factor XIIIa identified between ECSC and EMSC. The immunophenotypes of the ECSC and EMSC overlapped in the lower uterine segment. The functional status of the endometrium had no effect on the immunoprofile. The pattern of CD34 and CD10 immunostaining in stromal cells might be helpful in determining tumor involvement in uterine and cervical sites.

Aromatase Expression in Stromal Cells of Endometrioid Endometrial Cancer Correlates with Poor Survival

To assess the prognostic significance of intratumoral aromatase in endometrioid endometrial cancer, sections from 55 patients with endometrial cancer were evaluated for expression of aromatase using immunohistochemistry, and the correlation between aromatase expression and clinicopathologic parameters were analyzed. Immunohistochemical staining for aromatase was positive for 32 (58%), 20 (36%), and 19 (34%) patients in cancer epithelial cells, stromal cells, and myometrial cells around the flank invasion, respectively. In situ hybridization also detected aromatase mRNA in all three types of cells. RT-PCR analysis revealed that aromatase mRNA was 2.5 +/- 1.0 amol/mug total RNA (mean +/- SE; n = 7) in tumor tissue. Western blot analysis detected the expected aromatase protein size of 58 kDa in cancer tissues more abundantly than in cancer-free endometrium (n = 3). The immunoreactivity in stromal cells correlated positively with advanced surgical stage and poor survival. Survival analysis revealed that the immunoreactivity of stromal cells was a significant prognostic factor, independent of histologic grade, muscular invasion, and lymph node metastasis, but dependent on surgical stage. By contrast, the immunoreactivity of aromatase both in cancer epithelial cells and myometrial cells did not correlate with prognosis. To the best of our knowledge, this is the first evidence associating intratumoral aromatase expression in stromal cells and poor survival in endometrioid endometrial cancer. This positive linkage indicates that local expression of aromatase plays a role in tumor progression through the formation of in situ estrogens. In situ expression of aromatase may offer a potential target for management of endometrial cancers.

PHYLLODES TUMOR OF THE PROSTATE: LONG-TERM FOLLOWUP STUDY OF 23 CASES

Phyllodes tumor of the prostate is a rare neoplasm of uncertain malignant potential. We studied a large series of phyllodes tumors to define the combination of histological features that are most useful for predicting patient outcome. A total of 23 cases were obtained from our collective files from 1973 to 2002, and numerous clinical and pathological features were evaluated. A review of the reported cases of phyllodes tumor of the prostate was done. Patient age was 25 to 86 years (mean 55) and they usually presented with urinary obstructive symptoms and hematuria. The diagnosis was made in 18 tumors by transurethral resection, in 2 by enucleation, in 1 by tumor resection and in 2 by prostatectomy. We analyzed 5 histological features, including cellularity (scale of 1 to 3), cytologic atypia (scale of 1 to 3), the number of mitotic figures per 10 high power fields, the stroma-to-epithelium ratio (low or high) and necrosis (present or absent). This combination of features revealed that 14 cases were low grade phyllodes tumor, 7 were intermediate grade and 2 were high grade with the high grade cases characterized by increased cellularity, severe cytological atypia, more than 5 mitotic figures per 10 high power fields and a high stroma-to-epithelium ratio, indicating stromal overgrowth. Immunohistochemical studies of 8 tumors revealed consistent, intense cytoplasmic immunoreactivity in stromal cells for vimentin and actin, in luminal epithelial cells for prostate specific antigen, prostatic acid phosphatase and broad-spectrum keratin AE1/AE3, and in basal cells for high molecular weight keratin 34beta-E12. Recurrence was seen in 7 of 14 low grade tumors (50%) and in 1 patient low grade sarcoma emerged with subsequent distant metastases 14 years after initial diagnosis following 5 recurrences. Recurrence was seen in 6 of 7 intermediate grade tumors and low grade sarcoma emerged with subsequent abdominal wall metastases in 1 patient 11 years after initial diagnosis following 3 recurrences. The phyllodes tumor recurred in each patient with high grade tumors with a time to first recurrence of 6 and 0.2 years, respectively. Distant metastases developed in these 2 patients. Histological grading of prostatic phyllodes tumors is predictive of short-term outcome based on the combination of stromal cellularity, cytological atypia, number of mitotic figures and the stroma-to-epithelium ratio. However, these tumors usually recur after transurethral prostatic resection and they are often locally aggressive with time. The emergence of overt sarcoma and metastatic disease is more frequent than previously recognized. Complete resection at initial diagnosis appears to be indicated.

Phospholipase C-? Immunostaining in Human Breast Carcinoma: Clinical Significance and Correlations with Protease and Growth-Factor Receptor Species

: Cryostat sections of 73 invasive breast carcinomas were immunostained with a rabbit polyclonal antibody to phosphoinositide-specific phospholipase C-γ (PLC-γ), an enzyme that mediates signal transduction in tyrosine kinase growth-factor pathways. Degree of immunoreactivity was then correlated with clinicopathologic data (stage, ER status, recurrence) and immunostaining for tyrosine kinase growth-factor receptors (EGFR, ERBB-2) as well as selected “invasion-associated” proteases (cathepsin D, urokinase plasminogen activator, matrix metalloproteinases 2 and 9 [MMP-2, MMP-9]). Neoplastic epithelial populations were PLC-γ immunoreactive in 95% of tumors although staining was focally distributed (in <50% of cells) in 51% of positive cases. Forty-four percent also exhibited immunostaining of peritumoral, spindle-shaped cells (i.e., fibroblasts, endothelium, inflammatory cells). The degree of PLC-γ immunoreactivity in neoplastic epithelium was not significantly correlated with clinicopathologic features, growth factor receptor overexpression, or protease immunostaining. Stromal cell PLC-γ staining, however, was significantly associated with stromal cell immunoreactivity for cathepsin D (p = 0.03), urokinase plasminogen activator (p = 0.01), and MMP-2 (p = 0.04). Disease recurrences were also more frequent in tumors with stroma/spindle cell PLC-γ immunoreactivity (66% vs. 41%, p = 0.04). We conclude that PLC-γ immunostaining, compatible with increased tyrosine kinase pathway signaling activity, is observed not only in a high proportion of neoplastic breast epithelial populations but also in accompanying stromal cell populations in a significant number of cases. Concordance with protease immunoreactivity among peritumoral stromal cells suggests that tyrosine kinase signaling may participate in protease elaboration in vivo, possibly conferring aggressive clinical behavior.

High expression of the Glut1 glucose transporter in human brain hemangioblastoma endothelium.

The principal glucose transporter at the blood-brain barrier is Glut1, and GLUT1 expression is downregulated in high grade gliomas. In the present study, glucose transporter expression was studied in surgically resected hemangioblastoma tissue. Light microscopic immunochemistry indicated the high expression of the Glut1 glucose transporter isoform throughout the central vascular endothelium of this tissue. Glial fibrillary acidic protein (GFAP) was observed only at the tumor border, with no GFAP immunoreactivity in stromal cells, pericytes or endothelia in the central tumor regions. It is generally believed that more Glut1 is found in erythrocytes than any other cell, but quantitative electron microscopic immunogold analyses of Glut1-immunoreactive sites per micron of capillary membrane showed the Glut1 density in tumor endothelial membranes glucose transporter was 2-3-fold higher than in human red cells. In the same tissue samples, qualitative immunogold electron microscopy of human serum albumin indicated that this protein (MW 65,000) moved freely from the vascular space into pericapillary regions, confirming the leaky barrier characteristics of the hemangioblastoma. These studies show that Glut1 expression may be high in endothelia that are highly permeable and devoid of astroglial contacts. Thus, human cerebral hemangioblastomas may provide a novel system for studying the induction of Glut1 in the blood-brain barrier.

Distinct Subsets of Stromal Cells Confined to Unique Microenvironments in Human Endometrium Throughout the Menstrual Cycle

Human endometrial stroma exhibits rather uniform morphology throughout the endometrium. However, predecidualization develops characteristically around vessels and subsequently around glands and under surface epithelium, demonstrating existence of regional differences among stromal cells. Immunoreactivity of stromal cells in endometrial tissues from various phases of the menstrual cycle, as elucidated by employing monoclonal antibodies to cytokeratin, vimentin, very late antigen-1 (VLA-1), Ber-EP4, and HLA-DR, revealed presence of phenotypically distinct subsets of stromal cells confined to unique microenvironments throughout the menstrual cycle. All stromal cells strongly expressed vimentin and weakly expressed cytokeratin. However, Ber-EP4 positive stromal cells were distinctly confined around glands and to the subluminal regions of the surface epithelium. The intervening stromal cells were Ber-EP4 negative. The HLA-DR positive stromal cells were characteristically present in three different locations: around glands and under surface epithelium, around blood vessels and around HLA-DR positive lymphoid cells. From all antigens studied, only expression of VLA-1 in the stromal cells showed a characteristic change throughout the menstrual cycle. Stromal cells in the proliferative and early secretory phases were VLA-1 negative. However, VLA-1 characteristically developed initially in the HLA-DR positive cells around vessels and then in HLA-DR/Ber-EP4 positive cells around glands and under surface epithelium. Eventually, all stromal cells in the upper functionalis expressed VLA-1 in the late secretory phase of the menstrual cycle. These data underscore a heterogeneity in stromal cells not exemplified by their morphology. Also, they provide a basis for understanding the differences that the stroma exhibits in morphologic and functional differentiation throughout the menstrual cycle.