Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have used a recently described model in which a ras oncogene is expressed in cytokeratin 5 (K5)-expressing cells on doxycycline administration to explore the effects of this oncogene in salivary glands of adult mice. Inducible expression of a mutated K-ras gene under the control of the K5 promoter led to the development of hyperplastic and dysplastic epithelial lesions and carcinomas, with an incidence of 100% and a minimum latency of a week. All major salivary glands were affected, as well as a set of previously undescribed buccal accessory salivary glands located on the apex of the masseter muscle, close to the oral angle. The tumors appear to arise from the cytokeratin 5-positive basal cell compartment. Myoepithelial cells participated in the hyperplasias but not in carcinomas, because the tumors are negative for smooth muscle actin. Carcinomas did not accumulate immunoreactive p53 but are positive for p63, as assayed by immunohistochemistry using an antibody against the N terminus of DeltaN p63, a splice variant of p63 that can inhibit p53 transcriptional activity. In this study, we provide evidence that the ras oncogene, targeted to a specifically sensitive cell compartment within the salivary glands, can trigger a series of event that are sufficient for full carcinogenesis.
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PMID:Rapid development of salivary gland carcinomas upon conditional expression of K-ras driven by the cytokeratin 5 promoter. 1665 31

The diagnosis of hidradenocarcinoma is difficult due to a combination of factors including inconsistent nomenclature/ classification, rarity of the neoplasm, and variable morphology of cells composing the neoplasm. Immunohistochemistry has not been previously performed on a series of hidradenocarcinomas. We evaluated six cases of hidradenocarcinoma histologically and immunohistochemically using antibodies to gross cystic disease fluid protein-15 (GCDFP-15), carcino-embryonic antigen (CEA), epithelial membrane antigen (EMA), S-100 protein, keratin AE1/3, cytokeratin 5/6, p53, bcl-1, bcl-2, and Ki67. Histology suggested concurrent eccrine and apocrine differentiation of the cases. Ki67 and p53 staining was strongly positive in five of six tumors. The neoplasms stained with antibodies to CEA, S-100 protein, GCDFP-15, EMA, bcl-1, and bcl-2 in no consistent pattern. All tumors studied stained positively for keratin AE1/3 and cytokeratin 5/6. In making the diagnosis of hidradenocarcinoma, it may be unnecessary to separate hidradenocarcinoma into eccrine and apocrine categories, and although Ki67 and p53 may be helpful, histological parameters remain paramount.
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PMID:Hidradenocarcinoma: a histological and immunohistochemical study. 1708 91

Microarray profiling of invasive breast carcinomas has identified subtypes including luminal A, luminal B, HER2-overexpressing, and basal-like. The poor-prognosis, basal-like tumors have been immunohistochemically characterized as estrogen receptor (ER)-negative, HER2/neu-negative, and cytokeratin 5/6-positive and/or epidermal growth factor receptor (EGFR)-positive. The aim of this study was to determine the prevalence of basal-like ductal carcinoma in situ in a population-based series of cases using immunohistochemical surrogates. A total of 245 pure ductal carcinoma in situ cases from a population-based, case-control study were evaluated for histologic characteristics and immunostained for ER, HER2/neu, EGFR, cytokeratin 5/6, p53, and Ki-67. The subtypes were defined as: luminal A (ER+, HER2-), luminal B (ER+, HER2+), HER2 positive (ER-, HER2+), and basal-like (ER-, HER2-, EGFR+, and/or cytokeratin 5/6+). The prevalence of breast cancer subtypes was basal-like (n = 19 [8%]); luminal A, n = 149 (61%); luminal B, n = 23 (9%); and HER2+/ER-, n = 38 (16%). Sixteen tumors (6%) were unclassified (negative for all 4 defining markers). The basal-like subtype was associated with unfavorable prognostic variables including high-grade nuclei (P < .0001), p53 overexpression (P < .0001), and elevated Ki-67 index (P < .0001). These studies demonstrate the presence of a basal-like in situ carcinoma, a potential precursor lesion to invasive basal-like carcinoma.
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PMID:Identification of a basal-like subtype of breast ductal carcinoma in situ. 1723 68

Cryopreserved equine ocular squamous cell carcinoma (SCC) was inoculated subcutaneously into 15 athymic nude and 15 SCID mice. Xenotransplantation resulted in tumor growth in two athymic nude mice and 1 SCID mouse. Histological appearance and immunohistochemical characterization using cytokeratin 5/6 markers and p53 markers of the tumor grown in mice was in full accord with the original equine tumors. No evidence of metastasis was noted in any mouse. This model may serve as a relevant in vivo model for studying the biology of equine ocular SCC and for the testing of new therapeutic modalities.
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PMID:Xenotransplantation of cryopreserved equine squamous cell carcinoma to athymic nude and SCID mice. 1736 32

Although epidemiological studies have suggested a positive correlation between environmental radon exposure and prostate cancer, the mechanism involved is not clear. In the present study, we examined the oncogenic transforming potency of alpha-particles using non-tumorigenic, telomerase-immortalized human benign prostate epithelial cells. We report the malignant transformation of human benign prostate epithelial cells after a single exposure to 0.6 Gy dose of alpha-particles. Transformed cells showed anchorage-independent growth in soft agar and induced progressively growing tumors when transplanted into SCID mice. The tumors were characterized histologically as poorly differentiated adenocarcinomas. The cell line derived from tumor (SCID 5015), like the unirradiated cells, expressed cytokeratin 5, 8 and 18, NKX3.1 and AMACR. The malignant cells showed increased secretion of MMP2. Stepwise chromosomal changes in the progression to tumorigenicity were observed. Chromosome abnormalities were identified in both irradiated and tumorigenic cells relative to the non-irradiated control cells. Prominent changes in chromosomes 6, 11 and 16, as well as mutations and deletions of the p53 gene were observed in the tumor outgrowth and tumor cells. These findings provide the first evidence of malignant transformation of human benign prostate epithelial cells exposed to a single dose of alpha-particles. This model provides an opportunity to study the cellular and molecular alterations that occur in radiation carcinogenesis in human prostate cells.
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PMID:Malignant transformation of human benign prostate epithelial cells by high linear energy transfer alpha-particles. 1767 80

The objective of this study was to evaluate the coexpression patterns of hormonal markers in breast cancer tissue and their relationship with pathologic characteristics and epidemiologic risk factors. We evaluated the expression of 17 markers by immunohistochemistry in 842 invasive breast carcinomas collected in a population-based case-control study conducted in Poland. Based on marker correlations, factor analysis identified four major coexpression patterns (factors): "nuclear receptor factor" [estrogen receptor (ER)-alpha, progesterone receptor, androgen receptor, cyclin D1, and aromatase], "estrogen metabolism/ER-beta factor" (ER-beta, peroxisome proliferator-activated receptor-gamma, steroid sulfatase, estrogen sulfonotransferase, and cytochrome P450 1B1), "HER2 factor" (human epidermal growth factor receptor 2, E-cadherin, cyclooxygenase-2, aromatase, steroid sulfatase), and "proliferation factor" (cytokeratin 5, cytokeratin 5/6, epidermal growth factor receptor, P53). Three of these factors corresponded to molecular subtypes previously defined by expression profiling; however, the estrogen metabolism/ER-beta factor seemed to be distinctive. High scores for this factor were associated with high tumor grade (P heterogeneity = 0.02), younger age at menarche (P heterogeneity = 0.04), lower current body mass index among premenopausal women (P heterogeneity = 0.01), and older age at menopause (P heterogeneity = 0.04). High scores for the proliferation factor were also associated with early menarche (P heterogeneity < 0.0001), and in contrast to the estrogen metabolism/ER-beta factor, higher current body mass index among premenopausal women (P heterogeneity = 0.03). Our analysis of hormonal pathway markers independently confirmed several previously defined molecular subtypes identified by gene expression profiling and augmented these findings by suggesting the existence of additional relationships related to ER-beta and enzymes involved in hormone metabolism.
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PMID:Hormonal markers in breast cancer: coexpression, relationship with pathologic characteristics, and risk factor associations in a population-based study. 1796 31

To update the data on the expression of 'mesothelioma markers' by serous carcinomas of various sites we have studied cases from ovary (n=56), endometrium (n=37), fallopian tube (n=6), primary peritoneum (n=5) and cervix (n=3) using a panel of antibodies (WT1, P53, estrogen receptors, HER2/neu, D2-40, cytokeratin 5/6 and E-cadherin). Ovarian carcinomas demonstrated D2-40 and cytokeratin 5/6 immunoreactivity in 23.2 and 55.4% of cases, respectively. Endometrial carcinomas demonstrated D2-40 and cytokeratin 5/6 immunoreactivity in 43.2 and 37.8% of cases, respectively. D2-40 staining pattern was predominantly focal; however, strong reactivity was identified in 16.2% of endometrial and 10.7% of ovarian carcinomas. HER2/neu oncoprotein overexpression was demonstrated in 7 of 37 (18.9%) uterine serous carcinomas. In contrast, all the serous carcinomas of the other sites were HER2/neu negative. The proportion of positive cases was significantly different in ovarian vs endometrial carcinomas regarding WT1 (P=0.0458), estrogen receptors (P<0.001) reactivity and HER2/neu overexpression (P=0.0025). D2-40 and cytokeratin 5/6 are expressed in a considerable proportion of serous carcinomas and should be used cautiously in a 'mesothelioma panel' in situations where serous carcinoma is in the differential diagnosis. HER2/neu was exclusively overexpressed in serous carcinomas of endometrial origin.
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PMID:Immunophenotyping of serous carcinoma of the female genital tract. 1856 94

Breast cancer in the young is considered a special clinical presentation of the disease. Sixty-nine breast cancer cases diagnosed at or before the age of 35 were analyzed for common morphological and immunophenotypical features of basal-like carcinomas. Sixteen carcinomas displayed the immunophenotypical characteristics (estrogen receptor and HER2 negativity and positivity for at least one of the following basal markers: cytokeratin 5 or 14, epidermal growth factor receptor, p63) of basal-like carcinomas, and most of them demonstrated characteristic histological features (pushing borders, lymphocytic peritumoral infiltrate, central hypocellular zone or necrosis, high mitotic rate) too. These tumors were more likely to be high-molecular-weight cytokeratin: 34betaE12 and p53 positive by immunohistochemistry. The presence of a basal-like phenotype can be important as concerns systemic treatment issues and could theoretically be associated with a higher rate of BRCA1 mutations in the young, because of the overlap of BRCA1 mutation associated breast carcinomas and the basal-like phenotype.
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PMID:Basal phenotype in breast carcinoma occurring in women aged 35 or younger. 1875 48

Breast cancer is the most frequent malignant tumor in women and the diagnosis, prognosis and therapeutic strategy are based on the pathologic report. In last years, it was shown that conventional pathologic diagnosis brings few data about prognosis and tells nothing about the response of the tumor to specific therapy. In an effort to improve the molecular characterization of breast cancer, gene profile analysis was performed in a large number of cases. Based on this analysis, there were characterized five molecularly different subclasses: basal-like, luminal type A and B, HER-2, and unclassified. It was shown that prognosis and response to adjuvant therapy is significantly different in these five subtypes. Immunohistochemistry was demonstrated to be a good and acceptable surrogate of the gene analysis. A panel of antibody that includes estrogen receptors (ER), progesterone receptors (PR), Her2 protein, cytokeratin 5 (CK5), epidermal growth factor receptor (EGFR), p53 mutation, and Bcl-2 expression, can discriminate between these five molecular subclasses. In the present review there are presented the main characteristics of the molecular subclasses, the relationships with the conventional pathologic classification, critical problems of the molecular classification and their impact on prognosis and therapy.
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PMID:From conventional pathologic diagnosis to the molecular classification of breast carcinoma: are we ready for the change? 1922 40

Breast cancer is a heterogeneous disease that includes several molecular types, characterized by the expression profile of sex hormone receptors, HER2 protein, cytokeratin 5, p53, and Bcl-2. EGFR is an additional marker predominantly expressed by basal-like carcinoma, but its significance in the other types is not completely understood. The aim of this study was to analyze the immunohistochemical expression of EGFR and its relationships with other factors of prognosis. There were investigated benign lesions and 84 cases with invasive breast carcinoma that were submitted first to the molecular classification. Next, we performed the staining for EGFR and two patterns of the final product of reaction were described. EGFR expression was found in 41.66% of the cases with basal-like carcinoma, in 50% of the cases with luminal B carcinoma, and in 21.42% of the cases with HER2 overexpression. A significant correlation was found between EGFR expression and degree of differentiation and distant metastasis. No significant correlation was found with the lymph node status, excepting for the basal-like carcinoma in which an inverse correlation was noticed. Our results suggest that EGFR expression by tumor cells of the breast cancer defines a specific subset of tumors with poor prognosis and potential resistance to the adjuvant therapy.
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PMID:Immunohistochemical expression and significance of epidermal growth factor receptor (EGFR) in breast cancer. 1943 14


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