Although they have slightly lower than the expected survival rates of patients with nonbrainstem tumors, patients with brainstem metastases may achieve effective palliation after stereotactic radiosurgery and WBRT.

Chrysin, apigenin, and luteolin are flavones that differ in their number of hydroxyl groups in the B ring. In this study, we investigated the protection by chrysin, apigenin, and luteolin against tert-butyl hydroperoxide (tBHP)-induced oxidative stress and the possible mechanisms involved in rat primary hepatocytes. Chrysin, apigenin, and luteolin dose-dependently up-regulated the protein expression of heme oxygenase 1 (HO-1) and glutamate cysteine ligase (GCL) catalytic (GCLC) and modifier subunit (GCLM) and increased the intracellular glutathione (GSH) content and the ratio of GSH to oxidized GSH. Among the flavones studied, chrysin showed the greatest induction of HO-1, GCLC, and GCLM protein expression and GSH content. Cellular reactive oxygen species production induced by tBHP was attenuated by pretreatment with chrysin, apigenin, and luteolin (P < .05), and this protection was reversed by the GCL inhibitor l-buthionine-S-sulfoximine and the HO-1 inhibitor zinc protoporphyrin. Chrysin, apigenin, and luteolin activated extracellular signal-regulated protein kinase 2 (ERK2), nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation, nuclear Nrf2-antioxidant responsive element (ARE) binding activity, and ARE-dependent luciferase activity. Both ERK2 and Nrf2 siRNAs attenuated chrysin-induced HO-1, GCLC, and GCLM protein expression. Taken together, these results suggest that chrysin, apigenin, and luteolin inhibit tBHP-induced oxidative stress by up-regulating HO-1, GCLC, and GCLM gene transcription via the ERK2/Nrf2/ARE signaling pathways in rat primary hepatocytes.

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Lycopene has been shown to inhibit tumor metastasis in vitro, but it is unclear whether lycopene is antimetastatic in vivo. Here, nude mice were orally supplemented 2 times per week for 12 wk with a low or high dose of lycopene [1 or 20 mg/kg body weight (BW)] or with beta-carotene (20 mg/kg BW). Two weeks after the beginning of supplementation, mice were injected once with human hepatoma SK-Hep-1 cells via the tail vein. Plasma levels of matrix metalloproteinase (MMP)-2 and vascular endothelial growth factor (VEGF) increased gradually in tumor-injected mice (tumor controls) following tumor injection but were markedly lowered by lycopene or beta-carotene supplementation. Ten weeks after tumor injection, mice were killed and tumor metastasis was found to be confined to the lungs. Compared with the tumor controls, high-lycopene supplementation lowered the mean number of tumors from 14 +/- 8 to 3 +/- 5 (P < 0.05) and decreased tumor cross-sectional areas by 62% (P < 0.05). High-lycopene supplementation also decreased the positive rate of proliferating cellular nuclear antigen (PCNA), the level of VEGF, and protein expressions of PCNA, MMP-9, and VEGF in lung tissues. However, high-lycopene increased the protein expression of nm23-H1 (an antimetastatic gene) by 133% (P < 0.001). For most variables measured, effects of lycopene were dose dependent and the effect of beta-carotene was between those of high-dose and low-dose lycopene. These results show that lycopene supplementation reduces experimental tumor metastasis in vivo and suggest that such an action is associated with attenuation of tumor invasion, proliferation, and angiogenesis.

Content of protocatechuic acid (PA) in eight locally available fresh fruits was analyzed, and the protective effects of this compound in diabetic mice were examined. PA at 1%, 2%, and 4% was supplied to diabetic mice for 8 weeks. PA treatments significantly lowered plasma glucose and increased insulin levels. PA treatments at 2% and 4% significantly lowered plasminogen activator inhibitor-1 activity and fibrinogen level; increased plasma activity of antithrombin-III and protein C; decreased triglyceride content in plasma, heart, and liver; elevated glutathione level and the retention of glutathione peroxidase and catalase activities in heart and kidney. PA treatments at 2% and 4% also significantly lowered plasma C-reactive protein and von Willebrand factor levels and reduced interleukin-6, tumor necrosis factor-alpha, and monocyte chemoattractant protein-1 levels in heart and kidney. These results support that protocatechuic acid could attenuate diabetic complications via its triglyceride-lowering, anticoagulatory, antioxidative, and antiinflammatory effects.