Pancreatic ductal adenocarcinoma has a median survival of less than 6 months from diagnosis. This is due to the difficulty in early diagnosis, the aggressive biological behaviour of the tumour and a lack of effective therapies for advanced disease. Mammalian heparanase is a heparan-sulphate proteoglycan cleaving enzyme. It helps to degrade the extracellular matrix and basement membranes and is involved in angiogenesis. Degradation of extracellular matrix and basement membranes as well as angiogenesis are key conditions for tumour cell spreading. Therefore, we have analysed the expression of heparanase in human pancreatic cancer tissue and cell lines. Heparanase is expressed in cell lines derived from primary tumours as well as from metastatic sites. By immunohistochemical analysis, it is preferentially expressed at the invading edge of a tumour at both metastatic and primary tumour sites. There is a trend towards heparanase expression in metastasising tumours as compared to locally growing tumours. Postoperative survival correlates inversely with heparanase expression of the tumour reflected by a median survival of 34 and 17 month for heparanase negative and positive tumours, respectively. Our results suggest, that heparanase promotes cancer cell invasion in pancreatic carcinoma and could be used as a prognostic indicator for postoperative survival of patients.

By hydrogenation of fluorene 1 using different catalysts, mixtures containing variable amounts of the six possible diastereomers of perhydrofluorene 2 were obtained. The 13C NMR spectra of all diastereomers have been determined in these mixtures whithout previous separation procedures. By molecular mechanics calculations the structures of the preferred conformations were simulated for all diastereomers. The substituent induced 13C NMR chemical shifts in conformers were calculated by using increments for the non‐bonding 1,3‐synaxial interactions. Three stereochemical increments, combined with the shift values found earlier by Beierbeck and Saunders, were sufficient to calculate the chemical shift differences of conformers empirically. The assignment of relative configurations of the diastereomers was possible by comparison of the empirically calculated and experimental 13C chemical shifts of the clearly distinguishable bridgehead carbons. The difference between calculated and experimentally determined shift values was only 1.3 ppm, averaged over all bridgehead carbons.

Synthese und Eigenschaften von Metall(II) und Metall(III) Bis‐Chelaten des 1,3‐Dithiol‐2‐selon‐4,5‐diselenolats (dsise) vom Typ (Bu4N)n[M(dsise)2](n = 2: M = Zn, Cd, Hg, Cu, Ni, Pd; n = 1:M = Ni, Au) werden beschrieben und im Vergleich mit isologen 1,3‐Dichalkogenol‐2‐chalkogenon‐4,5‐dichalkogenolat‐Chelaten diskutiert (IR, 13C‐NMR, EPR, Cyclovoltammetrie). Anhand von ab‐initio‐SCF‐Rechnungen wird die bei der Synthese des dsise und des 1,3‐Dithiol‐2‐selon‐4,5‐dithiolats (dmise) auftretende „Umlagerung”︁ charakterisiert. Die röntgenkristallographischen Daten von (Bu4N)2[Ni(dsise)2] (Raumgruppe P21/c, a = 8,5556(13) Å, b = 15,0009(12) Å, c = 19,696(3) Å, β = 96,018(7)°, V = 2513,9(5) Å3, (Z = 2) und von Bu4N[Ni(dsise)2] (Raumgruppe C2/c, a = 25,133(6) Å, b = 9,828(4) Å, c = 18,104(7) Å, β = 132,81(1)°, V = 3281(2) Å3, Z = 4) werden vorgestellt.

TM (1998)

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