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A Celis

Publications and source records attributed to A Celis.

At least 19 recordsLinked to original sources

Proteomics and immunohistochemistry define some of the steps involved in the squamous differentiation of the bladder transitional epithelium: a novel strategy for identifying metaplastic lesions.

Here, we present a novel strategy for dissecting some of the steps involved in the squamous differentiation of the bladder urothelium leading to squamous cell carcinomas (SCCs). First, we used proteomic technologies and databases (http://biobase.dk/cgi-bin/celis) to reveal proteins that were expressed specifically by fresh normal urothelium and three SCCs showing no urothelial components. Thereafter, antibodies against some of the differentially expressed proteins as well as a few known keratinocyte markers were used to stain serial cryostat sections (immunowalking) of biopsies obtained from bladder cystectomies of two of the SCC-bearing patients (884-1 and 864-1). Because bladder cancer is a field disease, we surmised that the urothelium of these patients may exhibit a spectrum of abnormalities ranging from early metaplastic stages to invasive disease. Immunohistochemical analysis revealed three types of non-keratinizing metaplastic lesions (types 1-3) that did not express keratins 7, 8, 18, and 20 (expressed by normal urothelium) and could be distinguished based on their staining with keratin 19 antibodies. Type 1 lesions showed staining of all cell layers in the epithelium (with differences in the staining intensity of the basal compartment), whereas type 2 lesions exhibited mainly basal cell staining. Type 3 lesions did not stain with keratin 19 antibodies. In cystectomy 884-1, type 3 lesions exhibited the same immunophenotype as the SCC and may be regarded as precursors to the tumor. Basal cells in these lesions did not express keratin 13, suggesting that the tumor, which was also keratin 13 negative, may have arisen from the expansion of these cells. Similar results were observed with cystectomy 864-1, which showed carcinoma in situ of the SCC type. SCC 864-1 exhibited both keratin 19-negative and -positive cells, implying that the tumor arose from the expansion of the basal cell compartment of type 2 and 3 lesions. Besides providing with a novel strategy for revealing metaplastic lesions, our studies have shown that it is feasible to apply powerful proteomic technologies to the analysis of complex biological samples under conditions that are as close as possible to the in vivo situation.

Biomarkers, Tumor↗

A comprehensive protein resource for the study of bladder cancer: http://biobase.dk/cgi-bin/celis.

In our laboratories we are exploring the possibility of using proteome expression profiles of fresh bladder tumors (transitional cell carcinomas, TCCs; squamous cell carcinomas, SCCs) and random biopsies as fingerprints to subclassify histopathological types and as a starting point to search for protein markers that may form the basis for diagnosis, prognosis, and treatment. Ultimately, the goal of these studies is to identify signaling pathways and components that are affected at various stages of bladder cancer progression and that may provide novel leads in drug discovery. Here we present our ongoing efforts to establish comprehensive two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) databases of TCCs and SCCs which are being constructed based on the proteomic and immunohistochemical analysis of hundreds of fresh tumors, random biopsies and cystectomies received shortly after operation (http://biobase.dk/cgi-bin/celis).

Animals↗

Short-term culturing of low-grade superficial bladder transitional cell carcinomas leads to changes in the expression levels of several proteins involved in key cellular activities.

Fresh, superficial transitional cell carcinomas (TCCs) of low-grade atypia (3 grade I, Ta; 6 grade II, Ta), as well as primary cultures derived from them were labeled with [35S]methionine for 16 h, between 2 and 6 days after inoculation. Whole protein extracts were subjected to IEF (isoelectric focusing) two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) followed by autoradiography. Proteins were identified by a combination of proteomic technologies that included microsequencing, mass spectrometry, 2-D PAGE immunoblotting and comparison with the bladder TCC protein database available on the internet (http://biobase.dk/cgi-bin/celis). Comparison of the IEF 2-D gel protein profiles of fresh tumors and their primary cultures showed that the overall expression profiles were strikingly similar, although differing significantly in the levels of several proteins whose rate of synthesis was differentially regulated in at least 85% of the tumor/culture pairs as a result of the short-term culturing. Most of the proteins affected by culturing were upregulated and among them we identified components of the cytoskeleton (keratin 18, gelsolin and tropomyosin 3), a molecular chaperone (hsp 28), aldose reductase, GST pi, metastasin, synuclein, the calreticulin precursor and three polypeptides of unknown identity. Only four major proteins were downregulated, and these included two fatty acid-binding proteins (FABP:FABP5 and A-FABP) which are thought to play a role in growth control, the differentiation-associated keratin 20, and the calcium-binding protein annexin V. Proteins that were differentially regulated in only some of the cultured tumors included alpha-enolase, triosphosphate isomerase, members of the 14-3-3 family, hnRNPs F and H, PGDH, hsp (heat-shock protein) 60, BIP, the interleukin-1 receptor antagonist, the nucleolar protein B23, as well as several proteins of yet unknown identity. The suitability of in vitro bladder tumor culture models to study complex biological phenomena such as malignancy and invasion is discussed.

Carcinoma, Transitional Cell↗

Home drowning among preschool age Mexican children.

OBJECTIVES: To estimate the risk of drowning by different bodies of water in and near the home for children aged 1 to 4 years. SETTING: The Metropolitan Area of Guadalajara, Mexico. METHODS: A population case-control study. Cases (n=33) were children 1 to 4 years old who drowned at their home; controls (n=200) were a random sample of the general population. RESULTS: The risk of drowning for children whose parents reported having a water well at home was almost seven times that of children in homes without a water well (adjusted odds ratio (OR)=6.8, 95% confidence interval (CI)=2.2 to 20.5). Risk ratio estimates for other bodies of water were: swimming pools (OR=5.8, 95% CI=0.9 to 37.5), water barrel (OR=2.4, 95% CI=1.0 to 5.6), underground cistern (OR=2.1, 95% CI=0.8 to 5.2), and a basin front (courtyard pool to store water) of 35 or more litres (OR=1.8, 95% CI=0.8 to 4.4). CONCLUSION: Drowning at home is frequent in the Metropolitan Area of Guadalajara, but the causes are different from those reported in developed countries. Accordingly, the preventive strategies must also be different.

Accidents, Home↗

Loss of adipocyte-type fatty acid binding protein and other protein biomarkers is associated with progression of human bladder transitional cell carcinomas.

Multifocal recurrent papillary tumors provide a unique model system to study the molecular mechanisms underlying the steps involved in transitional cell carcinoma progression and offer a valuable source of material to search for biomarkers that may form the basis for diagnosis, prognosis, and treatment. We have examined the protein expression profiles of normal bladder urothelium and of 63 transitional cell carcinomas of various histopathological grades and T stages using high-resolution, two-dimensional gel electrophoresis, microsequencing, mass spectrometry, and a two-dimensional gel protein database approach for polypeptide identification (http://biobase.dk/cgi-bin/celis). In general, the results revealed a striking similarity between the overall qualitative expression patterns of papillary tumors of all grades, as well as of papillary and solid tumors of grade III. With few exceptions, tumors of grades I-III expressed, albeit at different levels, all of the keratins (7, 8, 13, 17, 18, 19, and 20) found in the normal urothelium. Grade IV tumors lacked or expressed reduced levels of keratin 13 but most resembled low-grade tumors. One invasive grade IV tumor, however, expressed a fibroblast-like protein phenotype. Four proteins that were expressed by normal urothelium and were lost at various stages of progression were identified as glutathione S-transferase mu, prostaglandin dehydrogenase (PGDH), a fatty acid binding protein with homology to the adipocyte isoform (A-FABP), and keratin 13. The percentage of tumors expressing A-FABP was very high in low-grade lesions but decreased drastically (P = 0.0006) in grade III and IV neoplasms. In addition, low-grade tumors contained more A-FABP than their high-grade counterparts. The stage of the disease was also statistically (P = 0.0269) related to the presence or absence of A-FABP in grade III tumors. Similar analysis of glutathione S-transferase mu and PGDH showed a statistically significant decrease of these proteins in high-grade (grades III and IV) tumors (P = 0.0026 and P = 0.0044, respectively). Only PGDH showed a suggestive correlation (P = 0.0775) with the stage of the disease in grade III tumors. Keratin 13 showed a drastic decrease in grade IV tumors. In addition to identifying biomarkers that may have prognostic value, our studies have suggested that A-FABP is an important component of the pathway(s) leading to bladder cancer development.

Biomarkers, Tumor↗

Identification of a group of proteins that are strongly up-regulated in total epidermal keratinocytes from psoriatic skin.

Analysis using two-dimensional (2D) gel electrophoresis of the [35S]-methionine-labelled proteins synthesized by non-cultured total epidermal keratinocytes obtained from normal and psoriatic skin revealed 6 proteins that are strongly up-regulated (5 times or more) in psoriatic skin. These proteins are synthesized at albeit lower levels by keratinocytes from normal and normal-appearing (uninvolved) skin of psoriatic patients, and correspond to isoelectric focusing sample spot numbers 4311 (40.3 kDa), 4003 (12.4 kDa), 5008 (11.9 kDa), 3012 (11.6 kDa), 6016 (11.6 kDa) and 1015 (10.1 kDa) in the normal keratinocyte 2D gel protein database [Celis et al, (1990) Electrophoresis, in press]. These proteins are also detected in the labelling medium indicating that they are at least in part secreted. Given their striking regulatory behavior, these proteins may play a role in the pathogenesis of psoriasis.

Electrophoresis, Gel, Two-Dimensional↗

A two-dimensional gel protein database of noncultured total normal human epidermal keratinocytes: identification of proteins strongly up-regulated in psoriatic epidermis.

A two-dimensional (2-D) gel database of proteins from noncultured total normal human epidermal keratinocytes has been established. A total of 1449 [35S]methionine labelled proteins (1112 isoelectric focusing, 337 nonequilibrium pH gradient electrophoresis) were resolved and recorded using computer assisted (PDQ-SCAN and PDQUEST software) 2-D gel electrophoresis. By matching the protein patterns of total keratinocytes and transformed human amnion cells (master database; Celis et al., Leukemia 1988, 2, 561-602) as well as by 2-D immunoblotting and microsequencing of keratinocyte proteins, it was possible to identify 72 polypeptides in the keratinocyte database. The database also includes data on polypeptides that are synthesized at a higher level by keratinocytes enriched in basal cells, and on six secreted proteins which are produced, albeit at a reduced rate, by normal keratinocytes and that are strongly up-regulated in psoriatic epidermis (Celis et al., FEBS Letters, in press).

Electrophoresis, Gel, Two-Dimensional↗

Two dimensional gel human protein databases offer a systematic approach to the study of cell proliferation and differentiation.

Human cellular protein databases have been established using computer-analyzed 2D gel electrophoresis. These databases, which include information on various properties of proteins, offer a global approach to the study of regulation of cell proliferation and differentiation. Furthermore, thanks to the advent of microsequencing the databases make it possible to directly link protein and DNA information.

Amino Acid Sequence↗

Human proteins IEF 58 and 57a are associated with the Golgi apparatus.

A mouse monoclonal antibody (mAB 22-II-D8B) raised against lysed transformed human amnion cells (AMA) has been characterized. The mAB decorated the Golgi apparatus in growing and quiescent cultured monolayer cells (fibroblasts and epithelial cells) of various species as determined by double immunofluorescence labeling and colocalization with galactosyltransferase antibodies. It reacted with the acidic human proteins IEF 58 (Mr = 29,000) and 57a, respectively (Mr = 30,000) (HeLa protein catalogue number; [(1982) Clin. Chem. 28, 766]), Golgi staining was also observed in BS-C-1 cells microinjected with mAB 22-II-D8B suggesting that the epitopes recognized by the antibody are most likely located on the cytoplasmic face of the membranes. The precise localization of the antigens to the various cisternae of the Golgi apparatus could not be demonstrated by immunogold cytochemistry on ultrathin cryosections due to either weak reactivity of the antibody or low concentration of the antigens. Immunofluorescence staining with mAB 22-II-D8B of lymphoid human Molt-4 cells and some human tissues failed to reveal any significant staining even though these expressed high levels of both IEF 58 and 57a. These results are taken to imply that the epitopes recognized by mAB 22-II-D8B may be masked in some cell types.

Animals↗

Towards establishing comprehensive databases of cellular proteins from transformed human epithelial amnion cells (AMA) and normal peripheral blood mononuclear cells.

Databases of protein information derived from the analysis of two-dimensional gels have been established from transformed human amnion cells (AMA) and peripheral blood mononuclear cells (PBMCs). A total of 1781 [35S]methionine-labeled AMA proteins (1274 IEF, 537 NEPHGE) and a total of 1311 proteins from PBMC (948 IEF, 363 NEPHGE) were resolved and recorded using computerized (PDQ-SCAN and PDQUEST softwares) two-dimensional gel electrophoresis. AMA and PBMC proteins (total, 454: 301 IEF, 153 NEPHGE) were matched both manually and by the computer. Information entered in the AMA database (in most cases for some major proteins) includes: molecular weight, protein name, HeLa protein catalogue number, mouse protein catalogue number, nuclear proteins, phosphorylated proteins, distribution of proteins in Triton X-100 supernatants and cytoskeletons, proliferation- and transformation-sensitive proteins, cell cycle-specific proteins, mitochondrial proteins, proteins matched in normal human embryonal lung MRC-5 fibroblasts and PBMC cells, heat shock proteins, proteins affected by interferons, cytoskeletal proteins, and the presence of antibody against protein in human sera. Additional information has been entered for the cell cycle-regulated and DNA replication protein cyclin (PCNA). Information entered in the PBMC database includes molecular weight and potential markers for sorted populations of lymphocyte subtypes. For those proteins that have been matched to AMA proteins, information contained in some entries may be transferred from the AMA database.

Amnion↗

Major proteins in normal human lymphocyte subpopulations separated by fluorescence-activated cell sorting and analyzed by two-dimensional gel electrophoresis.

We have compared the overall patterns of protein synthesis of normal human lymphocyte subpopulations taken from five volunteers using high resolution two-dimensional gel electrophoresis. The lymphocytes were isolated using density gradient centrifugation, labeled with subtype-specific MoAbs, and separated to a high degree of homogeneity by FACS into CD4+ helper T cells, CD8+ suppressor T cells, CD20+ B cells, and N901 (NHK-1)+ NK cells. The four lymphocyte subpopulations were labeled with [35S]methionine for 14 hr, solubilized in lysis buffer, and analyzed by two-dimensional gel electrophoresis (IEF). Of about 1000 proteins resolved in each case, most were found to be common to all subpopulations. However, eight putative markers for B1+ (proteins 5525, Mr = 63,700; 5621, Mr = 63,700; 8311, Mr = 36,900; 2202, Mr = 36,300; 6121, Mr = 30,300; 106, Mr = 29,300; 5009, Mr = 23,000; 8012, Mr = 11,600) and one for N901+ (protein 8129, Mr = 30,400) were identified. In contrast, no major protein markers were found that could differentiate T4+ and T8+ cells from each other or from B cells and NK cells. With the exception of two B1+ markers (proteins 5525 and 5621), lower but variable levels of the other markers were observed in all cell types. All the putative protein markers have been identified in the protein database of human peripheral blood mononuclear cells (PBMCs) (see accompanying article by Celis et al.). Comparison of the overall patterns of protein synthesis of the unsorted PBMCs with those of the four subpopulations showed that the synthesis of some major PBMC proteins decreased substantially in the sorted subsets. These proteins are most likely not of monocyte origin, as these cells constituted only about 15% of the total PBMCs. Also, the inhibition does not seem to be due to the addition of the single MoAbs or to cell cycle differences. Taken together, the data provide a background for further studies of protein profiles in normal (resting or activated) and malignant hematopoietic cells.

Antigens, Differentiation↗

Progressin: a novel proliferation-sensitive and cell cycle-regulated human protein whose rate of synthesis increases at or near the G1/S transition border of the cell cycle.

A novel proliferation-sensitive and cell cycle-specific basic protein, termed progressin (Mr = 33,000), has been identified in proliferating human cells of epithelial, fibroblast and lymphoid origin. Progressin is synthesized almost exclusively during the S-phase of transformed human amnion cells (AMA). Increased synthesis of this protein is first detected late in G1, at or near the G1/S transition border, reaches a maximum in mid to late S-phase, and declines thereafter. Contrary to histones, progressin synthesis is not coupled to DNA replication. As expected for an S-phase-specific protein, no detectable synthesis of progressin was observed in non-proliferating human MRC-5 fibroblasts and epidermal basal keratinocytes. Elevated, but variable levels of this protein were observed in proliferating normal fibroblasts and transformed cells of fibroblast, epithelial and lymphoid origin. Taken together the above observations suggest that progressin may be a component of the common pathway leading to DNA replication and cell division.

Cell Cycle↗

Cyclin (PCNA, auxiliary protein of DNA polymerase delta) is a central component of the pathway(s) leading to DNA replication and cell division.

Cyclin, also known as PCNA or the auxiliary protein of mammalian DNA polymerase delta, is a stable cell cycle regulated (synthesized mainly in S-phase) nuclear protein of apparent Mr 36,000 whose rate of synthesis correlates directly with the proliferative state of normal cultured cells and tissues. Cyclin (PCNA) is absent or present in very low amounts in normal non-dividing cells and tissues, but it is synthesized in variable amounts by proliferating cells of both normal and transformed origin. All available information indicates that this ubiquitous and tightly regulated DNA replication protein is a central component of the pathway(s) leading to DNA replication and cell division.

Animals↗

Levels of synthesis of primate-specific nuclear proteins differ between growth-arrested and proliferating cells.

A monoclonal antibody that reacts specifically with the proliferation-sensitive nuclear proteins, isoelectric focusing (IEF) 8Z30 and 8Z31 (molecular weight (MW), 76,000 charge variants, HeLa protein catalogue number) has been characterized. As determined by indirect immunofluorescence, the antibody stains the nucleolus and nucleoplasm of interphase-cultured cells of primate origin, but does not react with cells of other species. Proteins having similar MWs and isoelectric points as the human or monkey (primates) proteins were not observed in cultured cells of the following species: aves, bat, dog, dolphin, goat, hamster, mink, mouse, pisces, potoroo, rabbit and rat. Quantitative two-dimensional (2D) gel electrophoretic analysis of [35S]methionine-labeled proteins synthesized by normal (quiescent, proliferating) and SV40-transformed human MRC-5 fibroblasts revealed significant differences in the levels of synthesis of both IEF 8Z30 and 8Z31. In quiescent cells the main labelled product corresponded to IEF 8Z31 (ratio IEF 8Z31/8Z30, 2.3), while in the transformed cells the major product was IEF 8Z30 (ratio, 0.62). Normal proliferating fibroblasts exhibited similar levels of both proteins (ratio, 1.21). Combined levels of synthesis of both proteins were 1.50 and 1.20 times as high in the transformed cells as in the quiescent and proliferating cells, respectively. Similar results were observed in other pairs of normal and transformed human cells, such as WI38/WI38 SV40 and amnion/AMA. Modulation of the levels of synthesis of these proteins may play a role in cell proliferation.

Animals↗

Yeasts in juvenile periodontitis. Preliminary observations by scanning electron microscopy.

Through the use of the electron microscope, yeasts were found invading gingival connective tissue in juvenile periodontitis (JP). Samples (3-mm punch biopsies, including epithelium and underlying connective tissue) were taken apically to periodontal pockets before and after patient treatment with spiramycin. Some samples underwent in vitro treatment with spiramycin. Oval and round yeast cells were found before and after in vivo and after in vitro spiramycin treatment. Larger numbers of yeast cells were seen after spiramycin treatment indicating that their growth might be favored after patient treatment with this antibiotic. This observation has an obvious clinical implication. Budding processes, indicating active yeast multiplication, were observed. Some yeast cells also showed the presence of glycocalyx. Further studies on the role of yeast in the pathogenesis of JP are necessary.

Adolescent↗