In melanoma, several signaling pathways are constitutively activated. Among these, the protein kinase C (PKC) signaling pathways are activated through multiple signal transduction molecules and ...appear to play major roles in melanoma progression. Recently, it has been reported that tamoxifen, an anti-estrogen reagent, inhibits PKC signaling in estrogen-negative and estrogen-independent cancer cell lines. Thus, we investigated whether tamoxifen inhibited tumor cell invasion and metastasis in mouse melanoma cell line B16BL6. Tamoxifen significantly inhibited lung metastasis, cell migration, and invasion at concentrations that did not show anti-proliferative effects on B16BL6 cells. Tamoxifen also inhibited the mRNA expressions and protein activities of matrix metalloproteinases (MMPs). Furthermore, tamoxifen suppressed phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt through the inhibition of PKCα and PKCδ phosphorylation. However, other signal transduction factor, such as p38 mitogen-activated protein kinase (p38MAPK) was unaffected. The results indicate that tamoxifen suppresses the PKC/mitogen-activated protein kinase kinase (MEK)/ERK and PKC/phosphatidylinositol-3 kinase (PI3K)/Akt pathways, thereby inhibiting B16BL6 cell migration, invasion, and metastasis. Moreover, tamoxifen markedly inhibited not only developing but also clinically evident metastasis. These findings suggest that tamoxifen has potential clinical applications for the treatment of tumor cell metastasis.
A practical method for the asymmetric transfer hydrogenation of alpha-substituted ketones was developed utilizing oxo-tethered N-sulfonyldiamine-ruthenium complexes. Reduction by HCO2H and HCO2K in a ...mixed solvent of EtOAc/H2O allowed for the selective synthesis of halohydrins from 2-bromoacetophenone (98%) and 2-chloroacetophenone (>99%), leading to suppressed undesired side reactions stemming from formylation under the typical reaction conditions using an azeotropic 5:2 mixture of HCO2H and Et3N. A range of functional groups, such as halogens, methoxy, nitro, dimethylamino, and ester groups, were well tolerated, highlighting the potential of this method. Nearly complete selectivity with a preferable ee was maintained even with a substrate/catalyst (S/C) ratio of 5000. This catalyst system was also effective for the asymmetric reduction of alpha-sulfonated ketones without eroding the leaving group.
A practical method for the asymmetric transfer hydrogenation of α‐substituted ketones was developed utilizing oxo‐tethered N‐sulfonyldiamine‐ruthenium complexes. Reduction by HCO2H and HCO2K in a ...mixed solvent of EtOAc/H2O allowed for the selective synthesis of halohydrins from 2‐bromoacetophenone (98%) and 2‐chloroacetophenone (>99%), leading to suppressed undesired side reactions stemming from formylation under the typical reaction conditions using an azeotropic 5:2 mixture of HCO2H and Et3N. A range of functional groups, such as halogens, methoxy, nitro, dimethylamino, and ester groups, were well tolerated, highlighting the potential of this method. Nearly complete selectivity with a preferable ee was maintained even with a substrate/catalyst (S/C) ratio of 5000. This catalyst system was also effective for the asymmetric reduction of α‐sulfonated ketones without eroding the leaving group.
The use of methanol for the selective methylation of aromatic amines with RuHCl(CO)(PNHP) (PNHP = bis(2-diphenylphosphinoethyl)amine) is reported. Various aromatic amines were transformed into ...their corresponding monomethylated secondary amines in high yields at 150 °C with a very low catalyst loading (0.02–0.1 mol %) in the presence of KO t Bu (20–60 mol %). The catalyst precursor, RuHCl(CO)(PNHP), was converted to RuH(CO)2(PNHP)+ under the catalytic conditions and also serves as a highly effective catalyst. The robustness of this catalyst contributes to its outstanding catalytic activity, even under reaction conditions, in which CO is liberated from methanol.
Aim : Patients with severe aortic stenosis (AS) may have bleeding episodes due to the loss of high-molecular-weight (HMW) von Willebrand factor multimers (VWFMs). The absence of HMW-VWFMs and ...bleeding tendency are usually corrected after aortic valve replacement (AVR). To investigate the process of VWFM recovery and symptoms in patients with severe AS, we analyzed changes in VWF antigen (VWF : Ag) , ADAMTS13 activity (ADAMTS13 : AC) , and platelet thrombus formation under high shear stress conditions. Methods : Nine patients with severe AS undergoing AVR were analyzed. Results : Evident deficiency of HMW-VWFMs was observed in six patients before surgery, which was rapidly restored within 8 days after AVR. Median levels of VWF : Ag before surgery, on postoperative days (PODs) 1, 8, 15, and 22, and one year after AVR were 78.1%, 130%, 224%, 155%, 134%, and 142%, respectively. In contrast, ADAMTS13 : AC was 50.5%, 35.5%, 25.5%, 25.1%, 30.3%, and 84.6%, respectively. Preoperative thrombus formation but not surface coverage was significantly lower than that on POD 22, which was considered as normal level in each patient. Compared with preoperative levels, thrombus volume was significantly lower on POD 1, but rapidly increased by POD 8. Conclusion : Bleeding tendency and loss of HMW-VWFMs observed in patients with severe AS before surgery was rapidly corrected after AVR. Instead, patients were in a VWF-predominant state between POD 8 and 22.
We have previously identified 204 partial cDNA fragments (ADRG1–204) as antidepressant related genes/expressed sequence tags. Then, we developed our original cDNA microarrays, on which the 194 clones ...out of ADRG1–204 were spotted. With this ADRG microarray, we found that the expression of a spot, ADRG55, which representing cysteine string protein (CSP), was significantly increased in rat brain after chronic treatment with a selective serotonin reuptake inhibitor, sertraline. In the present study, reverse transcription-polymerase chain reaction analysis confirmed the induction of CSP at mRNA levels in rat frontal cortex after chronic treatment with two different classes of antidepressants, imipramine or sertraline. Western blot analysis also revealed that CSP-immunoreactivity was increased after antidepressant treatment. In conclusion, our data suggest that CSP is one of the common functional molecules induced after chronic antidepressant treatment.
In this study, we identified a novel splice variant of 70-kDa heat shock cognate protein (HSC70), while screening differentially expressed molecules in rat brain after chronic antidepressant ...treatment. This clone, named HSC49, lacked 470 bp of nucleotides of rat HSC70. HSC49 encoded 442 amino acid residues with a calculated molecular mass of 48.6 kDa. DNA sequence analysis revealed that HSC49 lacked the entire Exon 7 and Exon 8 of the HSC70 gene. Chronic treatment with antidepressant, imipramine or sertraline, induced a 38.5 or 22.5% increase in mRNA levels in rat frontal cortex, respectively, when compared to controls. Western blot analysis also revealed that the protein expression of HSC49 was increased after antidepressant treatment. Our data suggest that HSC49 may be one of the common molecules induced after chronic antidepressant treatment.
