Hepatocellular carcinoma (HCC) is a common malignancy worldwide and is a leading cause of death. To contribute to the development and improvement of molecular markers for diagnostics and prognostics and of therapeutic targets for the disease, we have largely expanded the currently available human liver tissue maps and studied the differential expression of proteins in normal and cancer tissues. Reference two-dimensional electrophoresis (2-DE) maps of human liver tumor tissue include labeled 2-DE images for total homogenate and soluble fraction separated on pH 3-10 gels, and also images for soluble fraction separated on pH 4-7 and pH 6-9 gels for a more detailed map. Proteins were separated in the first dimension by isoelectric focusing on immobilized pH gradient (IPG) strips, and by 7.5-17.5% gradient sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels in the second dimension. Protein identification was done by peptide mass fingerprinting with delayed extraction-matrix assisted laser desorption/ionization-time of flight-mass spectrometry (DE-MALDI-TOF-MS). In total, 212 protein spots (117 spots in pH 4-7 map and 95 spots in pH 6-9) corresponding to 127 different polypeptide chains were identified. In the next step, we analyzed the differential protein expression of liver tumor samples, to find out candidates for liver cancer-associated proteins. Matched pairs of tissues from 11 liver cancer patients were analyzed for their 2-DE profiles. Protein expression was comparatively analyzed by use of image analysis software. Proteins whose expression levels were different by more than three-fold in at least 30% (four) of the patients were further analyzed. Numbers of protein spots overexpressed or underexpressed in tumor tissues as compared with nontumorous regions were 9 and 28, respectively. Among these 37 spots, 1 overexpressed and 15 underexpressed spots, corresponding to 11 proteins, were identified. The physiological significance of the differential expressions is discussed.

Ferroelectric Cr-doped BiFeO3 (BFCr) thin films having a rhombohedrally distorted simple perovskite structure were fabricated on the p-type Si (100) substrate by the chemical solution deposition technique. The microstructures and the surface morphologies of BFCr thin films on the p-type Si (100) annealed at 550 °C for 30 min in nitrogen atmosphere were examined by an x-ray diffractometer and a scanning electron microscope, respectively. The capacitance-voltage (C−V) curves for BFCr thin film as the clockwise ferroelectric hysteresis loop were observed. Furthermore, the C−V characteristics for the metal-ferroelectrics-semiconductor structured BFCr thin films were measured as functions of the voltage and the frequency. From these results, the fixed charge density Nfc was calculated as 5.3×1011 cm−2. The leakage current characteristics of BFCr thin films were also measured by a thermally stimulated current measurement. Using the current-voltage curves, the current conduction mechanism of BFCr thin films on the p-type Si (100) capacitor was found to be dominated by the ferroelectric Schottky emission with a barrier height ϕB of 0.45±0.02 eV.

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