Adenocarcinoma of the minor duodenal papilla: report of a case.

We report a case of adenocarcinoma of the minor duodenal papilla, a rare type of duodenal neoplasm. A 76-year-old man with a history of surgery for rectal cancer and gastric cancer was referred to us after a follow-up upper gastrointestinal endoscopy revealed an abnormal elevation in the minor duodenal papilla. The pathological diagnosis of a biopsy specimen was adenocarcinoma. Preoperative examination of other organs revealed a tumor in the ascending colon, which was also identified as adenocarcinoma. We performed synchronous pancreatoduodenectomy and ileocecal resection with lymph node dissection. Histopathological examination of the resected specimen revealed that the papilla tumor arose from the duodenal mucosa and infiltrated the submucosa of the duodenal wall, but not the pancreatic parenchyma. Based on these findings, we diagnosed primary adenocarcinoma of the minor duodenal papilla. To our knowledge, this is only the sixth such case reported in the English-language literature, and we review all six cases after this case report.

Structure of Ultrathin Native Oxides on III-Nitride Surfaces.

When pristine material surfaces are exposed to air, highly reactive broken bonds can promote the formation of surface oxides with structures and properties differing greatly from bulk. Determination of the oxide structure is often elusive through the use of indirect diffraction methods or techniques that probe only the outermost layer. As a result, surface oxides forming on widely used materials, such as group III-nitrides, have not been unambiguously resolved, even though critical properties can depend sensitively on their presence. In this study, aberration corrected scanning transmission electron microscopy reveals directly, and with depth dependence, the structure of ultrathin native oxides that form on AlN and GaN surfaces. Through atomic resolution imaging and spectroscopy, we show that the oxide layers are comprised of tetrahedra-octahedra cation-oxygen units, in an arrangement similar to bulk θ-Al2O3 and ß-Ga2O3. By applying density functional theory, we show that the observed structures are more stable than previously proposed surface oxide models. We place the impact of these observations in the context of key III-nitride growth, device issues, and the recent discovery of two-dimensional nitrides.

Expression of proteinase-activated receptor-2 in human pancreatic cancer: a possible relation to cancer invasion and induction of fibrosis.

The proteinase-activated receptor-2 (PAR-2) is a G protein-coupled receptor that is cleaved and activated by trypsin. To clarify the presence of PAR-2 in human pancreatic cancer, the expression of PAR-2 was analyzed by RT-PCR, immunoblotting and immunocytochemistry using 5 human pancreatic cancer cell lines. And to evaluate the biological significance, immunohistochemical expression of PAR-2 in malignant and non-malignant human pancreatic tissues was examined using paraffin-embedded sections. The presence of PAR-2 was confirmed in all 5 pancreatic cancer cell lines and all 21 paraffin-embedded specimens from human pancreatic cancer examined. The expression of PAR-2 was found to be higher in the tissues with infiltrative growth pattern than those with expansive growth pattern. Moreover, significantly higher expression of PAR-2 was observed in the tissues which were accompanied by severe fibrosis. Even in the same specimen, the intensity of immunoreactivity tended to be stronger in the part with severe fibrosis than that with mild fibrosis. Similarly, the higher expression of PAR-2 was observed in chronic pancreatitis with severe fibrosis than with mild fibrosis. Taken together, these results suggest that the activation of PAR-2 is involved in cancer invasion and the induction of fibrosis in human pancreatic cancer.

Curcumin inhibits interleukin 8 production and enhances interleukin 8 receptor expression on the cell surface:impact on human pancreatic carcinoma cell growth by autocrine regulation.

BACKGROUND: Curcumin, the yellow pigment in turmeric, has been shown to prevent tumor progression in a variety of tissues in rodents. The authors investigated the effect of curcumin on human carcinoma cell lines to determine whether constitutive interleukin-8 (IL-8) production of tumor cells was correlated with nuclear factor kappaB (NF-kappaB) activation and cell growth activity. METHODS: A human pancreatic carcinoma cell line, SUIT-2, was incubated with various concentrations of curcumin for 2 hours. Biologic features, including IL-8 production, DNA binding activity, transactivation of NF-kappaB, cell growth activity, cell viability, and the expression of IL-8 receptors (CXCR1 and CXCR2) were analyzed. RESULTS: The constitutive production of IL-8 was inhibited by curcumin at concentrations of 10-100 microM in a dose dependent manner. NF-kappaB activity was reduced significantly by curcumin treatment. Pretreatment with curcumin inhibited the growth rate of carcinoma cells significantly. Such cell growth inhibition by curcumin was not recovered by exogenous recombinant IL-8. The investigation of expression in IL-8 receptors, CXCR1 and CXCR2, revealed that the expression of both receptors was enhanced remarkably by curcumin. Exogenous IL-8 could not recover this enhancement of IL-8 receptors. These results suggest that curcumin inhibits IL-8-induced receptor internalization. CONCLUSIONS: The authors concluded that curcumin contributed not only to the inhibition of IL-8 production but also to signal transduction through IL-8 receptors. These data suggest that curcumin reduces numerous IL-8 bioactivities that contribute to tumor growth and carcinoma cell viability. From this point of view, curcumin is a potent anticancer agent that inhibits the production of proinflammatory cytokines, including IL-8, by tumor cells.