In feline coronavirus (FCoV) pathogenesis, the ability to infect macrophages is an essential virulence factor. Whereas the low-virulence feline enteric coronavirus (FECV) isolates primarily replicate in the epithelial cells of the enteric tract, highly virulent feline infectious peritonitis virus (FIPV) isolates have acquired the ability to replicate efficiently in macrophages, which allows rapid dissemination of the virulent virus throughout the body.
Feline infectious peritonitis (FIP) is a fatal immunity
The mucin-like glycoprotein episialin (MUC1) is highly overproduced by a number of human carcinomas. We have shown previously in a variety of mammalian cell lines that overexpression of this very large transmembrane molecule diminishes cellular adhesion, suggesting that episialin/MUC1 overexpression may play an important role in tumor invasion and metastasis. By using in situ hybridization, we show here that episialin/ MUC1 mRNA expression can be increased more than 10-fold in breast carcinoma cells relative to the expression in adjacent normal breast epithelium. In search of the molecular mechanism of this overexpression, we observed that the episialin/MUC1 promoter contains a candidate binding site for transcription factors of the STAT family ϳ500 base pairs upstream of the transcription start site. Cytokines and/or growth factors such as interleukin-6 or interferon-␥ can activate STATs. In the human breast carcinoma cell line T47D, both compounds are able to stimulate transcription of a luciferase reporter gene under the control of a 750-base pair MUC1 promoter fragment proximal to the transcription start site. The observed increase is entirely mediated by the single STAT-binding site, since mutation of this site abolishes stimulation of the reporter by interleukin-6 and interferon-␥. In addition, mutation of the STAT site also decreased the promoter activity in nonstimulated T47D cells, suggesting that the STAT-binding site is among the elements that are involved in the overexpression of MUC1 in tumor cells. Episialin/MUC11 (also known as MUC1, PEM, CA 15-3 antigen, or EMA) is a transmembrane molecule with a large extracellular mucin-like domain. In normal cells episialin/ MUC1 is exclusively present at the apical side of the cell, but in carcinoma cells normal polarization is lost and episialin/MUC1 co-localizes with adhesion molecules such as integrins and cadherins. The long and relatively rigid extracellular domain of episialin/MUC1 can shield these adhesion molecules and diminish cellular adhesion, if present at a sufficiently high density on the cell surface (1-3). Overexpression of episialin/MUC1 in carcinoma cells has been frequently reported (4 -6) and is expected to have a similar effect on cellular behavior as loss of E-cadherin, the major epithelial cell-cell adhesion molecule, which has been shown to promote invasion and metastasis of carcinoma cells (for review see Refs. 7-9). Therefore, we have proposed that episialin/MUC1 also plays an important role in invasion and metastasis in vivo (10). Indeed, transgenic mice overexpressing episialin/MUC1 develop more aggressive lung tumors than nontransgenic mice, 2 whereas episialin/MUC1 null mice show a slower rate of tumor progression (11).Recent reports have shown that episialin overexpression in various types of neoplasia correlates with poor survival (12)(13)(14). Episialin/MUC1 is also the antigen that is measured in the CA 15-3 assay (the main blood marker to detect recurrence of breast cancer), and it is a molecule that is widely considered as ...
Current cervical cancer screening is based on morphological assessment of Pap smears and associated with significant false negative and false positive results. Previously, we have shown that detection of hypermethylated genes in cervical scrapings using quantitative methylation-specific PCR (QMSP) is a promising tool for identification of squamous cell cervical cancer. Aim of the present pilot-study was to evaluate presence of hypermethylated genes in cervical carcinogenesis, both in squamous cell as well as adenocarcinomas. Cervical scrapings were obtained from 30 patients diagnosed with cervical cancer (20 squamous cell carcinomas and 10 adenocarcinomas) and 19 women with histologically normal cervices. The scraped cells were used for determination of promoter hypermethylation by QMSP for 12 genes and for morphological assessment. Overall, CALCA, DAPK, ESR1, TIMP3, APC and RAR-b 2 promoters were significantly more often hypermethylated in cancers than in controls, while adenocarcinomas were more often hypermethylated above the highest control ratio for APC, TIMP3 and RASSF1A promoters. Combining 4 genes (CALCA, DAPK, ESR1 and APC) yielded a sensitivity of 89% (with all adenocarcinomas identified), equal to cytomorphology (89%) and high-risk human papilloma virus (Hr-HPV; 90%). The 4-gene QMSP proved theoretically superior to cytomorphology as well as Hr-HPV in specificity (100% vs. 83 and 68%, respectively), because cytology identified 3 controls as moderate or severe dyskaryosis and 6 controls were positive for Hr-HPV. In conclusions, QMSP of 4 gene promoters combined appears to have comparable sensitivity and potentially better specificity in comparison to ''classic'' cytomorphological assessment and Hr-HPV detection. QMSP holds promise as a new diagnostic tool for both squamous cell carcinoma and adenocarcinoma of the cervix. ' 2006 Wiley-Liss, Inc. Key words: methylation; cervical cancer; QMSP; DAPK; ESR1Cervical cancer is an important cause of death in women worldwide. 1 Cervical carcinogenesis is highly associated with (high-risk) human papilloma virus (HPV) infections. 2 Cytomorphological examination of cervical smears is a widely applied, though not ideal screening method for cervical cancer and its precursors, since the Pap smear has false negative rates of 2-40%, due to a combination of sampling error, processing artifacts and the nature of subjective interpretation. 1,3,4 False-negative cytology can also be found in about 50% of cases when previous negative smears are reviewed from the small proportion of screened women who develop invasive cancer. 4 Moreover, as many as 20% of all Pap smears are interpreted as atypical squamous cells of undetermined significance (ASCUS) or borderline dyskaryotic, leading to increased surveillance and more invasive tests in many of these patients. 3,5 The incidence of squamous cell carcinoma of the cervix has decreased since introduction of nation wide screening programs, compared to a relative increased incidence of adenocarcinoma of the cervix. 6 The efficacy of ...
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