Akt is a serine-threonine kinase that mediates a variety of cellular responses to external stimuli. During postnatal development, Akt signaling in the heart was up-regulated when the heart was rapidly growing and was down-regulated by caloric restriction, suggesting a role of Akt in nutrient-dependent regulation of cardiac growth. Consistent with this notion, reductions in Akt, 70-kDa S6 kinase 1, and eukaryotic initiation factor 4E-binding protein 1 phosphorylation were observed in mice with cardiac-specific deletion of insulin receptor gene, which exhibit a small heart phenotype. In contrast to wild type animals, caloric restriction in these mice had little effect on Akt phosphorylation in the heart. Furthermore, forced expression of Akt1 in these hearts restored 70-kDa S6 kinase 1 and eukaryotic initiation factor 4E-binding protein 1 phosphorylation to normal levels and rescued the small heart phenotype. Collectively, these results indicate that Akt signaling mediates insulin-dependent physiological heart growth during postnatal development and suggest a mechanism by which heart size is coordinated with overall body size as the nutritional status of the organism is varied.

These results strongly suggest that tumor-related factors induce and expand CD4(+)CD25high T regs.

Curcumin (diferuloylmethane) is a dietary phytochemical with low toxicity that exhibits growth-suppressive activity against a variety of cancer cells and possesses certain chemopreventive properties. Curcumin has already been the subject of several clinical trials for use as a treatment in human cancers. Synthetic chemical modifications of curcumin have been studied intensively in an attempt to find a molecule with similar but enhanced properties of curcumin. In this study, a series of novel curcumin analogues were synthesized and screened for anticancer activity. New analogues that exhibit growth-suppressive activity 30 times that of curcumin and other commonly used anticancer drugs were identified. Structurally, the new analogues are symmetrical 1,5-diarylpentadienone whose aromatic rings possess an alkoxy substitution at each of the positions 3 and 5. Analysis of the effects of the analogues on the expression of cancer-related genes usually affected by curcumin indicated that some induced the down-regulation of B-catenin, Ki-ras, cyclin D1, c-Myc, and ErbB-2 at as low as one eighth the concentration at which curcumin normally has an effect. The analogues,

Blood vessel recruitment is an important feature of normal tissue growth. Here, we examined the role of Akt signaling in coordinating angiogenesis with skeletal muscle hypertrophy. Hypertrophy of C2C12 myotubes in response to insulin-like growth factor 1 or insulin and dexamethasone resulted in a marked increase in the secretion of vascular endothelial growth factor (VEGF). Myofiber hypertrophy and hypertrophy-associated VEGF synthesis were specifically inhibited by the transduction of a dominant-negative mutant of the Akt1 serine-threonine protein kinase. Conversely, transduction of constitutively active Akt1 increased myofiber size and led to a robust induction of VEGF protein production. Akt-mediated control of VEGF expression occurred at the level of transcription, and the hypoxia-inducible factor 1 regulatory element was dispensable for this regulation. The activation of Akt1 signaling in normal mouse gastrocnemius muscle was sufficient to promote myofiber hypertrophy, which was accompanied by an increase in circulating and tissue-resident VEGF levels and high capillary vessel densities at focal regions of high Akt transgene expression. In a rabbit hind limb model of vascular insufficiency, intramuscular activation of Akt1 signaling promoted collateral and capillary vessel formation and an accompanying increase in limb perfusion. These data suggest that myogenic Akt signaling controls both fiber hypertrophy and angiogenic growth factor synthesis, illustrating a mechanism through which blood vessel recruitment can be coupled to normal tissue growth.

Background: Patients with gastric cancers producing alpha-fetoprotein (AFP) were reported to have a poor prognosis with high rates of liver metastasis. The purpose of the present study was to clarify the clinicopathological features of AFP-producing gastric cancers, in particular characteristics of liver metastasis, and to evaluate treatment of these cancers. Methods: In 27 of the 29 cases with elevated preoperative serum AFP levels among a total of 974 primary gastric cancers, AFP production was confirmed in gastric cancer cells by immunohistochemistry. These cases were included in the AFP-positive gastric cancer group (AFP(+), 2.7%). The remaining 945 cases with normal serum AFP levels were designated the AFP-negative gastric cancer group (AFP(–)). Results: There was a higher incidence of lymph node metastasis, a deeper invasion of the gastric wall, a higher frequency of advanced stage, a more marked lymphatic invasion and a higher rate of liver metastasis in the AFP(+) group than in the AFP(–) group. The patients received curative resection in AFP(+) group had a significantly worse survival rates in comparison to that in AFP(–) group. With respect to liver metastasis (n = 17) in AFP(+) group, of 3 cases who received curative hepatic resection, 1 patient survived more than 3 years, while the remaining 2 died in less than 3 years due to multiple liver recurrence. The patients (n = 5) who received palliative resection for liver metastasis followed by transarterial continuous infusion chemotherapy all died in less than 1 year. Conclusion: AFP-producing gastric cancers had aggressive behavior and their clinical or biological features were quite different from the common AFP-negative gastric cancers. Surgical resection of liver metastasis from AFP-producing gastric cancers was unsatisfactory. The development of a novel multimodal therapy against AFP-producing gastric cancers is needed.