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We investigated the effects of bicarbonate/lactate-buffered peritoneal dialysis fluid (B/L-PDF) and lactate-buffered PDF (L-PDF) on cell viability and apoptosis, focusing on monocarboxylate transporters (MCTs). MCT-1 transports lactate into cells. Cell viability and apoptosis of human peritoneal mesothelial cells (HPMCs) were examined by water-soluble tetrazolium salt-1 and TUNEL assays, respectively. The relative number of viable HPMCs was significantly decreased by L-PDF at 48 h (8.8 ± 0.4%) compared with cells cultured in M199, but not by B/L-PDF (66.7 ± 1.1%). Apoptosis was markedly induced by L-PDF at 48 h (69.3 ± 16.2%), but not by B/L-PDF (2.6 ± 0.3%). Knockdown of MCT-1 by small interfering RNA (siRNA) attenuated the L-PDF-induced reduction of viable cells and increased apoptosis compared with control siRNA, but MCT-4 knockdown had no effect. B/L-PDF had lesser effects on cell viability and apoptosis of HPMCs compared with L-PDF. These results suggest that B/L-PDF biocompatibility occurs by avoiding the induction of apoptosis in HPMCs.

The aurora kinases are serine/threonine kinases that are essential for mitosis and contribute to tumorigenesis. Therefore, aurora kinases hold promise for molecularly targeted therapy. In the present study, we demonstrated that aurora B kinase (AURKB) is overexpressed in both cisplatin- and oxaliplatin-resistant cells. Downregulation of AURKB sensitized cells to both cisplatin and oxaliplatin, but not to paclitaxel, 5-FU or hydrogen peroxide. Interestingly, we found that both cisplatin- and oxaliplatin-resistant cells were hypersensitive to the AURKB specific inhibitors, AZD1152 HQPA and ZM447439, suggesting that both cisplatin- and oxaliplatinresistant cells develop an addiction to AURKB. These data provide evidence that aurora kinase inhibitors can overcome both cisplatin and oxaliplatin resistance. Therefore, AURKB inhibitors could offer potential benefits if used after first-line platinum-based chemotherapy.

Phosphine-free hydrazone such as 1c was found to be an efficient ligand for the copper-catalyzed Goldberg-type N-arylation of amides and Ullmann-type N-arylation of azoles with aryl halides under mild conditions. A variety of N-arylamides and N-arylazoles were synthesized in good to high yields.

Background. To clarify the clinical significance of the expression of vascular endothelial growth factor (VEGF) and its receptor, kinase domain-containing receptor (KDR) in colorectal cancer, we evaluated the relationship between the expression of VEGF and KDR, and the microvessel counts and clinicopathological factors in colorectal cancer. Methods. A total of 259 specimens from sequential colorectal cancer patients who had undergone surgery were examined by the avidin-biotin peroxidase complex method, using anti-human VEGF, anti-human KDR, and anti-human von Willebrand factor antibodies. Results. The incidence of VEGF expression in the tumor cells of the patients with liver metastasis was significantly higher than that in the tumor cells of the patients without liver metastasis (67% vs 44%). The microvessel count at the tumor invasive edge in the patients whose tumor cells were positive for VEGF was significantly higher than that in the patients whose tumor cells were negative for VEGF (33.0 ± 7.8 vs 28.0 ± 7.9); the significant difference in microvessel counts was greater when there was a combination of VEGF and KDR expression. The overall survival rate of patients positive for VEGF was significantly (P = 0.0276) lower than that of those who were negative for VEGF. Although there was no significant difference (P = 0.0743) in the survival rates after potentially curative resection according to VEGF expression, the survival rate of the patients positive for both VEGF in tumor cells and KDR in endothelial cells was significantly (P = 0.0026) lower than that in the patients who were negative for VEGF and/or KDR. In addition, multivariate analysis revealed that the expression of both VEGF and KDR was an independent prognostic factor even after potentially curative resection. Conclusion. VEGF may be implicated in the definition of the malignant phenotype of colorectal cancer via tumor angiogenesis. VEGF and its receptor KDR expression in tumorous tissues could be useful prognostic factors in colorectal cancer.

The objectives of this study were to evaluate the effect of insulin-like growth factor I (IGF-I) on the fractional synthesis rate (FSR) of muscle and whole body protein breakdown rate (WPBR) during methionine-free total parenteral nutrition (MTPN). We also determined whether the inhibition of endogenous methionine availability reduced tumor protein synthesis. AH109A hepatoma cells were inoculated onto the backs of Donryu rats on day 0. On day 10, the rats were catheterized for TPN and assigned to one of four groups: 1) standard TPN (STPN), 2) STPN + IGF-I, 3) MTPN, or 4) MTPN + IGF-I. The addition of IGF-I to MTPN reduced the loss of body weight by both increasing muscle FSR and reducing WPBR. The tumor FSR did not differ between MTPN + IGF-I and MTPN. The methionine extraction ratio from the liver was negative with MTPN + IGF-I but positive in the other groups. We concluded that IGF-I blockage of endogenous methionine release from peripheral protein sites was associated with a shift to liver-derived methionine, with no change in tumor growth in MTPN-treated rats.

We have studied the expression of vascular endothelial growth factor (VEGF) in esophageal cancer using immunohistochemistry. A total of 101 specimens of esophageal cancer tissue were fixed by formalin, embedded in paraffin wax, and examined in 3μm sections by avidin-biotin peroxidase complex method. VEGF was noted in the cytoplasm of normal esophageal glandular cells, monocyte-macrophages, squamous carcinoma cells and of the vascular endothelial cells themselves. VEGF expression by monocyte-macrophages was observed in all cases, in contrast the incidence of VEGF expression in the tumor cells was relatively low at 26.7% of all specimens. However, in the cases where the tumor cells were positive for VEGF, it was discovered that the main source of the VEGF production was the tumor cells themselves. In the cases with proper mucosal invasion the incidence of VEGF expression by the tumor cells was quite low at 7.6%. However, when the tumor invaded the submucosal layer the expression increased to 33.3%. There was also a significant correlation in those with the submucosal invasion between the expression of VEGF in the tumor cells and the density of microvessels at the tumor invasive edge. These results suggest that VEGF may play an important role in tumor progression and in the angiogenesis via auto-crine and para-crine mechanisms in esophageal cancer.

Phosphine-free hydrazone such as 1c was found to be an efficient ligand for the copper-catalyzed Goldberg-type N-arylation of amides and Ullmann-type N-arylation of azoles with aryl halides under mild conditions. A variety of N-arylamides and N-arylazoles were synthesized in good to high yields.

A novel observation technique for secondary defects of ion implantation has been developed. Stripping of the surface by means of a combination of anodic oxidation and removal of the oxide has been found to expose the buried secondary defects induced by ion implantation. The defects observed by means of atomic force microscopy (AFM) show craterlike forms created by enhanced oxidation around the secondary defects. Detection of the defects with this technique is complementary to conventional transmission electron microscopy (TEM) observation. The technique is a promising method for clarifying the depth distribution of various defects. The technique has also been found to be advantageous for planar TEM observation.