Overexpression of GalNAc-transferase GalNAc-T3 promotes pancreatic cancer cell growth.

O-linked glycans of secreted and membrane-bound proteins have an important role in the pathogenesis of pancreatic cancer by modulating immune responses, inflammation and tumorigenesis. A critical aspect of O-glycosylation, the position at which proteins are glycosylated with N-acetyl-galactosamine on serine and threonine residues, is regulated by the substrate specificity of UDP-GalNAc:polypeptide N-acetylgalactosaminyl-transferases (GalNAc-Ts). Thus, GalNAc-Ts regulate the first committed step in O-glycosylated protein biosynthesis, determine sites of O-glycosylation on proteins and are important for understanding normal and carcinoma-associated O-glycosylation. We have found that one of these enzymes, GalNAc-T3, is overexpressed in human pancreatic cancer tissues and suppression of GalNAc-T3 significantly attenuates the growth of pancreatic cancer cells in vitro and in vivo. In addition, suppression of GalNAc-T3 induces apoptosis of pancreatic cancer cells. Our results indicate that GalNAc-T3 is likely involved in pancreatic carcinogenesis. Modification of cellular glycosylation occurs in nearly all types of cancer as a result of alterations in the expression levels of glycosyltransferases. We report guanine the nucleotide-binding protein, α-transducing activity polypeptide-1 (GNAT1) as a possible substrate protein of GalNAc-T3. GalNAc-T3 is associated with O-glycosylation of GNAT1 and affects the subcellular distribution of GNAT1. Knocking down endogenous GNAT1 significantly suppresses the growth/survival of PDAC cells. Our results imply that GalNAc-T3 contributes to the function of O-glycosylated proteins and thereby affects the growth and survival of pancreatic cancer cells. Thus, substrate proteins of GalNAc-T3 should serve as important therapeutic targets for pancreatic cancers.

Epstein-Barr virus-associated T-cell lymphoma: a case of eyelid swelling and intramuscular infiltration mimicking dermatomyositis.

Association with Epstein-Barr virus (EBV) infection has been noted in various types of cutaneous lymphoproliferative disorders. We report a 57-year-old Japanese woman with T-cell lymphoma mimicking dermatomyositis that was associated with chronic active EBV infection. She presented with low-grade fever, bilateral erythematous swellings on the eyelids, and necrotic papules on the face. Serum creatine kinase levels were elevated and a diffuse reticular shadow was detected in both lung fields. The infiltrate of atypical lymphocytes found in skin and muscle, which contained EBV-encoded small nuclear RNA-1 and EBV, was also detected in the CD4+ peripheral blood cells. Treatment with prednisolone resolved her lesions with no relapse for 3 years, after which there was a recurrence in her left lung. Combination chemotherapy was not effective against the lung lesion and she died with multiple organ failure 2 months after the recurrence.

Developmental expression of carbonic anhydrase-related proteins VIII, X, and XI in the human brain.

Three cDNA homologues of carbonic anhydrase with unknown biological functions have been reported: carbonic anhydrase-related proteins (CA-RP) VIII, X, and XI. In the present study, we produced monoclonal antibodies to these CA-RPs and studied their regional and cellular distributions in the human adult and fetal brains by immunohistochemical analysis. In the adult brain, CA-RP VIII was expressed in the neural cell body spreading to most parts of the brain. CA-RP X was expressed in the myelin sheath and its expression was shown in the cytoplasm of cultured tumor cells by immunocytochemical analysis. CA-RP XI was expressed in the neural cell body, neurites, and astrocytes in relatively limited regions of the brain. In the fetal brain, CA-RP VIII and XI were expressed in the neuroprogenitor cells in the subventricular zone as early as the 84th day of gestation and subsequently detected in the neural cells migrating to the cortex. CA-RP X first appeared in the neural cells in the cortex at the 141st day. In the choroid plexus, the epithelial cells gave CA-RP VIII and XI expressions in both adult and fetal brains. From the findings in the present study on the distribution and the developmental expression of CA-RP VIII, X, and XI in the human brain we suggest that these CA-RPs play roles in various biological process of the CNS.

cDNA sequence of human carbonic anhydrase-related protein, CA-RP X: mRNA expressions of CA-RP X and XI in human brain.

A full-length cDNA clone of human carbonic anhydrase-related protein (CA-RP) X was obtained and sequenced. The 2720 bp long cDNA sequence was predicted to encode a 328 amino acid polypeptide. The deduced amino acid sequence showed an overall similarity of 25-57% to other CA isozymes and the highest % similarity to a CA-RP XI. Similar to CA-RP XI, CA-RP X lacked two out of three zinc-liganded histidine residues, suggesting no biological activity of CA. Northern blot analysis demonstrated an approx. 2.8 kb transcript in the human brain and kidney. RNA dot blotting showed significant signals for CA-RP X and XI mRNA expressions in the adult total brain and almost all parts of the central nervous system, but no expression in the fetal brain. These results suggest that CA-RP X and XI play some role in human brain, especially in brain development.

Ruptured gastric fundal varices treated with endoscopic variceal ligation and transjugular retrograde obliteration: case report.

Therapeutic modalities for the obliteration of collateral vessels connecting the portal venous system with the systemic circulation, transjugular retrograde obliteration (TJO) and balloon-occluded retrograde transvenous obliteration have recently been developed, and several satisfactory results have been reported with their use. We report a case of ruptured gastric fundal varices treated with TJO after endoscopic variceal ligation (EVL). In our case, variceal bleeding was controlled successfully with EVL and varices were eradicated with TJO.

Remission of antiepiligrin (laminin-5) cicatricial pemphigoid after excision of gastric carcinoma.

PURPOSE: To describe a case of antiepiligrin cicatricial pemphigoid with unusual ocular manifestations and its remission after surgical removal of gastric carcinoma. METHODS: We describe a 61-year-old Japanese man with antiepiligrin cicatricial pemphigoid. RESULTS: He presented with conjunctival injection and discharge preceded by a 6-month period of erosive lesions in the oral mucosa and the truncal skin. An advanced gastric carcinoma was found and his serum immunoprecipitated laminin-5. Despite topical treatment with betamethasone, ofloxacin, and artificial tear solutions, serious symblepharon along the Meibomian line developed with little shortening of the inferior conjunctival sac. Following radical gastrectomy, the ocular and cutaneous lesions turned completely quiet. CONCLUSION: The present case differed from past cases by lacking inferior conjunctival sac shortening and by showing erosive lesions solely at the mucocutaneous junctions. The ocular involvement in this case correlated very well with the severity of gastric carcinoma.

A discrepant finding between magnetic resonance imaging and other imaging modalities suggests a microcystic serous cystadenoma of the pancreas.

BACKGROUND: Serous cystadenoma of the pancreas is generally considered as having no malignant potential. Thus, of clinical importance is a differential diagnosis of this neoplasm from other solid tumors that are often malignant. RESULTS: We report a case of microcystic serous cystadenoma of the pancreas. Abdominal ultrasonography, computed tomography, and endoscopic ultrasonography showed a solid mass in the body of the pancreas with a diameter of 15 mm, but magnetic resonance imaging revealed it as a unilocular cystic lesion. Histological examinations on the surgically resected tissue specimen showed a honeycombed tumor with innumerable tiny cysts appearing grossly as a solid mass. The discrepant finding between magnetic resonance imaging and other imaging modalities observed in this case is suggestive of and might be specific to microcystic serous cystadenoma of the pancreas. CONCLUSIONS: Magnetic resonance imaging is a mandatory modality to identify pancreatic serous cystadenoma that contains no visible cystic compartments on computed tomography and ultrasonography.

Antiepiligrin (laminin 5) cicatricial pemphigoid associated with an underlying gastric carcinoma producing laminin 5.

Although bullous pemphigoid and cicatricial pemphigoid are sometimes associated with malignancy, it remains uncertain whether such an association is pathogenetically related or just a coincidence attributable to the advanced age of the patients. We report a 61-year-old patient with antiepiligrin (laminin 5) cicatricial pemphigoid (AeCP) associated with an advanced gastric carcinoma. The gastric carcinoma cells in this patient were shown to produce laminin 5 by immunofluorescence microscopy, and the patient's serum contained autoantibodies directed against laminin 5 on immunoprecipitation. Furthermore, the blistering symptoms and the titre of antibasement membrane zone antibodies coordinately changed with the resection and subsequent relapse of the gastric cancer. These observations suggest that the gastric carcinoma producing laminin 5 may have induced the production of autoantibodies to this laminin, which were pathogenic to the skin and mucous membranes in this patient. This report demonstrates a link between this autoimmune subepithelial blistering disease and malignancy. It is of interest and potential great importance to examine other cases of AeCP for such a potential association.

Immunohistochemical analysis of platelet-derived growth factor and its receptors in fibrohistiocytic tumors.

Platelet-derived growth factor (PDGF) is known to stimulate the proliferation of fibroblasts, although the role of PDGF and its receptors in the development of fibrohistiocytic tumors has not been clarified. In this study, we investigated this role by immunohistochemically staining PDGF and PDGF beta-receptors in paraffin-embedded dermatofibroma (DF), dermatofibrosarcoma protuberans (DFSP) and malignant fibrous histiocytoma (MFH) tissue. We also immunohistochemically investigated the relationship between PDGF beta-receptors and CD34, which is a known immunohistochemical marker for DFSP. Immunohistochemical studies using anti-PDGF-AA or BB antibodies showed that PDGF-AA and BB was found in 20 to 40% of the tumor cells in DF, DFSP, and MFH. No definite relationship for each tumor type was found. The expression of PDGF beta-receptors in DFSP and that of MFH tissue was significantly greater in comparison to DF and scar tissue. The expression of CD34 and PDGF beta-receptors in DFSP was observed in identical areas. These findings suggest that autocrine or paracrine growth stimulation, through PDGF beta-receptors, is related to the tumorous proliferation of fibrohistiocytic tumors, and the expression of PDGF beta-receptors might play a role in the proliferation of CD34 positive tumor cells.

Nonscarring inflammatory epidermolysis bullosa acquisita with esophageal involvement and linear IgG deposits.

A 24-year-old woman with autoimmune thrombocytopenia and hypothyroidism had an inflammatory bullous eruption in the mouth, face, and trunk that left no milia or scars after healing. Histologic examination revealed a subepidermal bulla and a neutrophil infiltration. Direct immunofluorescence examination showed deposition of IgG and C3 in the basement membrane zone (BMZ). Indirect immunofluorescence examination with 1M sodium chloride-split skin showed IgG binding to the dermal side. Immunoblot analysis demonstrated IgG autoantibodies reacting with 290 kD dermal protein. We diagnosed this as epidermolysis bullosa acquisita (EBA) with a nonscarring inflammatory feature. Treatment with oral dapsone, 75 mg, and prednisolone, 20 mg, cleared the eruption. Reduction of the prednisolone dosage was associated with multiple erosions in the esophagus. Direct immunofluorescence examination revealed linear deposition of IgG in the esophageal BMZ. To our knowledge, this is the first report of EBA with esophageal involvement and deposition of IgG in the BMZ of the esophagus.

[A flow cytometric study of the effects of benzalkonium chloride on the cell cycle].

The effects of benzalkonium chloride (BAK) on the cell cycle of Chang's cultured human conjunctival cells were investigated by a flow cytometer (FCM). The cells were exposed to BAK solutions for 60 sec and after 12-48 hrs were fixed in 20% ethanol, treated by 0.25% RNase and stained by 0.005% propidium iodide. DNA histograms were analyzed by the FCM. As a result, although many cells were damaged by exposure to solutions of 0.0025% or 0.005% BAK, they began to grow again 48 hrs later. BAK decreased red fluorescence intensity in DNA histograms. The histogram shifted to the left 12 hrs after the cells were exposed to 0.0025% or 0.005% BAK solutions and recovered 48 hrs later. The DNA synthetic phase of the cell cycle was inhibited by exposure to solutions of 0.0025% BAK and then recovered 48 hrs later.

Agarose gel electrophoresis with nitroblue tetrazolium coloration for determination of glycated lipoproteins in serum from diabetics.

We describe a simple method for determining glycated lipoproteins (glc LPs) in serum by agarose gel film electrophoresis, with color development with nitroblue tetrazolium. The resulting blue bands on the film were measured densitometrically at 545 nm to quantify alpha-, pre beta-, and beta-glc LPs. Each glc LP concentration (mmol/L) was calculated from the resulting percentage multiplied by the value for serum fructosamine. Only glc beta-LP was significantly correlated with the atherogenic index: low-density LP-cholesterol/high-density LP-cholesterol (r = 0.545, P less than 0.01). The concentration of glc beta-LP in sera from diabetics was 2.2-fold higher (0.84 mmol/L) than that (0.38 mmol/L) in normal individuals. Diabetic patients with complications had higher concentrations of glc beta-LP, with large individual variations, than did patients without complications, the greatest concentration (1.02 mmol/L) being found in patients with diabetic retinopathy and (or) nephropathy. The concentration of glc beta-LP (glc LDL) in serum seems to depend on the extent and duration of hyperglycemia; it may also be a useful diagnostic indicator of diabetic atherogenesis, microangiopathy (e.g., retinopathy or nephropathy), and other complications.