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Abstract: Objective: Impaired glucose tolerance (IGT) is an independent risk factor for atherosclerotic cardiovascular disease. However, due to the lack of appropriate animal models, the underlying mechanisms for IGT-induced atherosclerosis remain to be elucidated in vivo. We recently used selective breeding to establish 2 mouse lines with distinctively different susceptibilities to diet-induced glucose intolerance, designated selectively bred diet-induced glucose intolerance-resistant (SDG-R) and SDG-prone (SDG-P), respectively. Here, we assessed atherosclerotic lesion formation in these mice. Methods: Female SDG-R and SDG-P mice were fed an atherogenic diet (AD; 1.25% cholesterol, 0.5% sodium cholate, and 36% energy as fat) for 20 weeks (8–28 weeks of age). Oral glucose tolerance tests were performed during the AD-feeding period. Atherosclerotic lesion formation was quantitatively analyzed in serial aortic sinus sections by oil red O staining. Plasma lipids were measured after the AD-feeding period. Results: Glucose tolerance was impaired in SDG-P mice as compared to SDG-R mice over the 20-week AD-feeding period. No significant differences were observed in any plasma lipid measurement between the 2 mouse lines. Aortic sinus atherosclerotic lesion formation in SDG-P mice was approximately 4-fold greater than that in SDG-R mice. Conclusion: In 2 mouse lines with different susceptibilities to diet-induced glucose intolerance, IGT accelerated atherosclerotic lesion formation. These mice may therefore serve as useful in vivo models for investigating the causal role of IGT in the pathogenesis of atherosclerosis. [Copyright &y& Elsevier]

Abstract: The effect of IL-10 antisense oligodeoxynucleotides (ODN) on the susceptibility of burned mice to intradermal (i.d.) infection of methicillin-resistant Staphylococcus aureus (MRSA) was studied. Abscesses formed and sepsis did not develop in normal mice infected i.d. with 108 CFU/mouse of MRSA. Similarly, sepsis caused by MRSA i.d. infection did not develop and abscesses formed in burned mice treated with IL-10 antisense ODN. However, all of the burned mice treated with scrambled ODN (control group) died by infectious complications stemming from MRSA i.d. infection, and an MRSA-abscess did not form in these mice. Macrophages (Mϕ) isolated from the infection site tissue of burned mice that were treated with IL-10 antisense ODN were identified as M1Mϕ, while Mϕ isolated from burned mice that were treated with scrambled ODN were shown to be M2Mϕ. MRSA-abscesses formed in burned mice inoculated with M1Mϕ, and these mice resisted a lethal dose of MRSA i.d. infection. However, an abscess did not form, and sepsis caused by MRSA i.d. infection developed in burned mice that were inoculated with M2Mϕ. These results indicate that severely burned mice treated with IL-10 antisense ODN are resistant against i.d. infection with MRSA. M1Mϕ appeared in the infection site tissues of severely burned mice that were treated with IL-10 antisense ODN may play a role on the abscess formation and inhibiting sepsis caused by MRSA i.d. infection. [Copyright &y& Elsevier]

Abstract: Neoxanthin and fucoxanthin, which have the characteristic structure of 5,6-monoepoxide and an allenic bond, were previously found to reduce the viability of human prostate cancer cells most intensively among 15 dietary carotenoids tested. In the present study, the induction of apoptosis in PC-3 cells by these two carotenoids was characterized by morphological changes, DNA fragmentation, an increased percentage of hypodiploid cells, and cleavages of caspase-3 and PARP. The ratio of apoptotic cells reached more than 30% after treatment for 48h with 20μM carotenoids. They reduced the expression of Bax and Bcl-2 proteins, but not Bcl-XL. Fucoxanthin accumulated in the cells at the same level as neoxanthin. Moreover, fucoxanthinol, a deacetylated product of fucoxanthin, formed in the cells treated with fucoxanthin and reached a level comparable to that of fucoxanthin after incubation for 24h. Treatment by fucoxanthinol alone also induced apoptosis in PC-3 cells. Thus, neoxanthin and fucoxanthin treatments were found to induce apoptosis through caspase-3 activation in PC-3 human prostate cancer cells. [Copyright &y& Elsevier]

Neoxanthin, a major carotenoid in green leafy vegetables, was reported to exhibit potent antiproliferative effect via apoptosis induction on human prostate cancer cells. However, the metabolic fate of dietary neoxanthin in mammals remains unknown. In the present study, we investigated the gastrointestinal metabolism of neoxanthin in mice and the in vitro digestion of spinach, and estimated the antiproliferative effect of neoxanthin metabolites on PC-3 human prostate cancer cells. Two hours after the oral administration to mice of purified neoxanthin, unchanged neoxanthin and stereoisomers of neochrome (8'-R/S) were detected in the plasma, liver, and small intestinal contents. To estimate the effect of intragastric acidity on the conversion of dietary neoxanthin into neochrome (epoxide-furanoid rearrangement), spinach was digested in vitro by incubating it with a pepsin-HCl solution at pH 2.0 or 3.0 (gastric phase) followed by a pancreatin-bile salt solution (intestinal phase). Spinach neoxanthin was largely converted into (R/S)-neochrome during the digestion when the gastric phase was set at pH 2.0, whereas the rearrangement was observed to a lesser extent at pH 3.0. (R/S)-neochrome dose-dependently inhibited the proliferation of PC-3 cells as well as neoxanthin at concentrations < or = 20 micromol/L. Although neoxanthin induced evident apoptotic cell death, (R/S)-neochrome inhibited the cell proliferation without obvious apoptosis induction. These results indicate that dietary neoxanthin is partially converted into (R/S)-neochrome by intragastric acidity before intestinal absorption and that (R/S)-neochrome exhibits an antiproliferative effect on PC-3 cells by the induction of cytostasis. [ABSTRACT FROM AUTHOR]

A yeast-based growth interference assay was developed utilizing a yeast strain in which expression of Xenopus cyclin A1 was induced to elevate cell division cycle 28 (Cdc28) kinase activity. Since the hyperactivation of Cdc28 kinase in yeast results in a growth-arrest phenotype, compounds which could rescue the cyclin A1-induced growth arrest might be potential new, antitumor drug candidates acting on the cyclin-dependent, kinase-mediated, cell cycle regulation pathway. In the course of our microbial screening program, the new Streptomyces metabolites, belactosins, were identified. As reported previously, belactosin A induced cell cycle arrest at G2/M phase in human cancer cells. However, the molecular mechanism of action was unknown. We herein demonstrate the proteasome inhibition by belactosin A. Belactosin A did not inhibit yeast Cdc28 kinase and human cyclin-dependent kinase in vitro. On the other hand, it inhibited the chymotrypsin-like activity of the rabbit 20S proteasome. From the initial SAR studies, we identified a hydrophobic belactosin A derivative, KF33955, which exhibited a 100-fold greater growth-inhibitory activity against HeLa S3 cells than belactosin A, presumably due to its higher cell permeability. The biochemical analysis using KF33955 suggested that the proteasome inhibitory activity of KF33955 were irreversible and required the β-lactone moiety to inhibit the proteasome. KF33955 increased the intracellular levels of protein ubiquitination in NIH3T3 cells. In addition, KF33955 treatment resulted in the accumulation of known proteasome substrates in HeLa S3 cells. These results identify belactosin A as a useful lead compound to target proteasome for the treatment of disease whose etiology is dependent on the unregulated ubiquitin–proteasome pathway. [Copyright &y& Elsevier]

Curcumin and its structurally related compounds (curcuminoids), the phenolic yellowish pigments of turmeric, display antioxidative, anticarcinogenic and hypocholesterolemic activities. In this study, we investigated the effects of dietary supplemented curcuminoids [commercial grade curcumin: a mixture of curcumin (73.4%), demethoxycurcumin (16.1%) and bisdemethoxycurcumin (10.5%)] on lipid metabolism in rats. Male Sprague-Dawley rats were assigned to three diet groups (n = 6) and fed a moderately high-fat diet (15 g soybean oil/100 g diet) for 2 wk. One diet group did not receive supplements (CONT), while the others were supplemented with 0.2 g curcuminoids/100 g diet (CUR0.2) or 1.0 g curcuminoids/100 g diet (CUR1.0). Liver triacylglycerol and cholesterol concentrations were significantly lower in CUR1.0 rats than in CONT rats. Plasma triacylglycerols in the VLDL fraction were also lower in CUR1.0 rats than in CONT rats (P < 0.05). Hepatic acyl-CoA oxidase activity of both the CUR0.2 and CUR1.0 rats was significantly higher than that of CONT rats. Furthermore, epididymal adipose tissue weight was significantly reduced with curcuminoid intake in a dose-dependent manner. These results indicate that dietary curcuminoids have lipid-lowering potency in vivo, probably due to alterations in fatty acid metabolism. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that tocotrienol (T3) has antiatherogenic effects. However, the T3 preparations used in those studies contained considerable amounts of tocopherol (Toc), which might affect the biological activity of T3. There is little information on the effect of highly purified T3 on atherosclerosis formation. This study investigated the effect of high-purity T3 on atherosclerotic lesion formation and the underlying mechanisms. Male apolipoprotein E knockout (apoE-KO) mice were fed a cholesterol-containing diet either alone or supplemented with T3 concentrate (Toc-free T3) or with α-Toc for 12 weeks. ApoE-KO mice fed the 0.2% T3-supplemented diet showed reduced atherosclerotic lesion formation in the aortic root. The 0.2% T3 diet induced Slc27a1 and Ldlr gene expression levels in the liver, whereas the α-Toc-supplemented diet did not affect those expression levels. T3 was predominantly deposited in fat tissue in the T3 diet-fed mice, whereas α-Toc was preferentially accumulated in liver in the α-Toc diet-fed mice. Considered together, these data demonstrate that dietary T3 exerts anti-atherosclerotic effect in apoE-KO mice. The characteristic tissue distribution and biological effects of T3, that are substantially different from those of Toc, may contribute to the antiatherogenic properties of T3. [ABSTRACT FROM AUTHOR]

Abstract: Proteasome inhibitors are currently a focus of increased attention as anticancer drug candidates. We recently performed systematic structure–activity relationship studies of the peptidic natural product belactosin A and identified non-peptidic derivative 2 as a highly potent proteasome inhibitor. However, the cell growth inhibitory effect of 2 is only moderate, probably due to the biologically unstable β-lactone warhead. Peptide epoxyketones are an important class of proteasome inhibitors exhibit high potency in cellular systems based on the efficient α,β-epoxyketone warhead. Importantly, belactosin derivatives bind primarily to the primed binding site, while peptide epoxyketones bind only to the non-primed binding site of proteasome, suggesting that hybridization of them might lead to the development of a new class of proteasome inhibitors. Thus, we successfully identified a novel chemotype of proteasome inhibitors 3 and 4 by rational structure-based design, which are expected to bind to both the primed and non-primed binding sites of proteasome. [Copyright &y& Elsevier]

• A combination therapy with anti-PD-1 antibody and STAT3 inhibitor was performed. • Humanized MHC-deficient NOG mouse was used for in vivo study against pancreatic cancer. • Unexpectedly, the combination remarkably reduced the anti-tumor effect and TIL numbers. • The combination of anti-PD-1 antibody with signal inhibitors should be carefully evaluated. • The present approach may be helpful to develop effective combination regimen using ICB. Recently, clinical studies using anti-immune checkpoint molecule antibodies have been successful in solid tumors, such as melanoma and non-small cell lung cancers. However, pancreatic cancers are still intractable and difficult to treat once recurrence or metastasis occurs; thus, novel combined use of immune checkpoint blockade (ICB) with molecular targeted drugs is considered a therapeutic option. Previously, we developed a novel humanized MHC-double knockout (dKO) NOG mouse model and demonstrated that an anti-PD-1 antibody or a STAT3 inhibitor showed anti-tumor effects through an immunological mechanism. In the current study, using a humanized mouse model, we aimed to develop a combination therapy with an anti-PD-1 antibody and a STAT3 inhibitor (STX-0119) for use in vivo against pancreatic cancer. In an in vitro investigation, STX-0119 showed weak to moderate cytotoxic activity against several pancreatic cancer cell lines, which exhibited activated pSTAT3 and weak PD-L1 expression. However, unexpectedly, an in vivo study indicated that the combination of the anti-PD-1 antibody with STX-0119 remarkably reduced the anti-tumor effect and TIL numbers despite the effective anti-tumor activity against pancreatic cancer was produced individually by STX-0119 and the anti-PD-1 antibody. These results suggested that the combination of an anti-PD-1 antibody with specific signal inhibiting drugs should be carefully evaluated to avoid unexpected side effects, and such studies might contribute to the development of an effective combination regimen of ICB with cancer-targeting drugs such as tyrosine kinase inhibitors (TKIs). [ABSTRACT FROM AUTHOR]

Background: Laparoscopic hepatic resection has been developed as a minimally invasive surgery; however, laparoscopic repeat minor hepatic resection (LRH) carries a higher risk of damage to other organs because of postoperative changes to and losses of anatomical landmarks. The current standard approach at many facilities has been to perform open repeat minor hepatic resection (ORH). This paper describes the surgical outcomes, procedure safety, and utility of ORH versus LRH, as well as the laparoscopic techniques used in LRH.Methods: Between February 2010 and May 2018, the data of 142 patients who underwent LRH or ORH at a single institution were retrospectively reviewed. Surgical outcomes, procedure safety, and procedure utility data were analyzed.Results: Forty-five patients underwent LHR and 97 patients underwent ORH. The conversion rate from LHR to OHR was 13.3%. After propensity score matching (PSM), the estimated blood loss was significantly lower in the LRH group than in the ORH group (50 mL vs. 350 mL; P < 0.001). The LRH group had an 8.1% complication rate, while the ORH group had a complication rate of 24.3% (P = 0.044). The postoperative length of stay was significantly shorter in the LHR group than in the OHR group (9 days vs. 11 days) (P = 0.024).Conclusion: LRH can be performed safely using various surgical devices. More favorable results are achieved with LRH than with ORH in terms of surgical outcomes including intraoperative bleeding, postoperative complications, and postoperative lengths of stay. [ABSTRACT FROM AUTHOR]

Background: Postoperative chemotherapy for treating colorectal liver metastasis (CLM) has been introduced with the aim of improving therapeutic outcomes. However, there is no consensus on the utility of multidisciplinary treatments with postoperative chemotherapy. Therefore, we evaluated surgical outcomes in patients with CLMs who underwent hepatectomy, while focusing on the effects of post-hepatectomy chemotherapy on remnant liver regeneration.Methods: Two hundred ninety patients who underwent hepatectomy were retrospectively analyzed using propensity score matching. Postoperative outcomes were evaluated with a focus on the effects of post-hepatectomy chemotherapy on regeneration of the remnant liver in patients with CLM. The remnant liver volumes (RLVs) were measured postoperatively using multi-detector computed tomography on day 7 and months 1, 2, 5, and 12 after the operation.Results: RLV regeneration and postoperative blood laboratory data did not differ significantly between patients who received postoperative chemotherapy and those who did not receive postoperative chemotherapy immediately after surgery or at any time point from postoperative day 7 to postoperative month 12. The recurrence rates, including same and other segmental intrahepatic recurrences, as well as the resection frequency of the remnant liver were not significantly different between the two groups.Conclusion: Postoperative chemotherapy may be of small significance for patients with CLM in terms of the remnant liver volume regeneration and functional recovery. [ABSTRACT FROM AUTHOR]

Background: Post-hepatectomy liver regeneration is of great interest to liver surgeons, and understanding the process of regeneration could contribute to increasing the safety of hepatectomies and improving prognoses.Methods: Five hundred thirty-eight patients who underwent hepatectomy were retrospectively analyzed. Postoperative outcomes were evaluated, with a focus on the effects of portal vein resection and resected liver volume on remnant liver regeneration in patients with liver tumors. Remnant liver volumes (RLVs) and laboratory data were measured postoperatively using multidetector computed tomography on day 7 and months 1, 2, 5, 12, and 24 after the operation.Results: Liver regeneration speed peaked at 1 week postoperatively and gradually decreased. Regeneration with large resections was longer than that with small resections, with the remnant liver regeneration rate being significantly lower in the former at all time points. Remnant liver regeneration plateaued around 5 months postoperatively, when regeneration is almost complete. Up to 1 month postoperatively, laboratory data were significantly worse when more portal veins was resected. After 2 months postoperatively, these data recovered to near normal levels.Conclusion: The speed and rate of remnant liver regeneration primarily showed a strong correlation with the number of resected portal veins and the amount of removed liver parenchyma. The larger the resection ratio, the longer it took the liver to regenerate. We confirmed that recovery of the liver's functional aspects accompanies recovery of the RLV. [ABSTRACT FROM AUTHOR]

Kynurenine is biosynthesised from tryptophan catalysed by indoleamine 2,3-dioxygenase (IDO). The abrogation of kynurenine production is considered a promising therapeutic target for immunological cancer treatment. In the course of our IDO inhibitor programme, formal cyclisation of the isothiourea moiety of the IDO inhibitor 1 afforded the 5-Cl-benzimidazole derivative 2b-6 , which inhibited both recombinant human IDO (rhIDO) activity and cellular kynurenine production. Further derivatisation of 2b-6 provided the potent inhibitor of cellular kynurenine production 2i (IC 50  = 0.34 µM), which unexpectedly exerted little effect on the enzymatic activity of rhIDO. Elucidation of the mechanism of action revealed that compound 2i suppresses IDO expression at the protein level by inhibiting STAT1 expression in IFN-γ-treated A431 cells. The kynurenine-production inhibitor 2i is expected to be a promising starting point for a novel approach to immunological cancer treatment. [ABSTRACT FROM AUTHOR]

Anticancer 2-aminoquinazolines were evaluated by their photophysical properties responding to media changes. By binding to the colchicine binding site of β-tubulin, the fluorescence emission of 2- N -morpholino-derivative ( 1 ) was blue-shifted with enhanced intensity. These distinguished features were used for the development of a β-tubulin colchicine site competition assay and visualization of the intracellular distribution of 1 by fluorescence microscopy. [ABSTRACT FROM AUTHOR]

STAT3 is considered to be a key molecule to mediating tumor-induced immunosuppression in various manners at tumor sites, by acting through immune-regulatory cytokines derived from the tumor cells. Specific anti-STAT3 inhibitors have been developed using nude mouse models transplanted with human tumor cells. However, mouse systems cannot accurately represent the human immune response induced by STAT3 inhibitors, and more humanized therapeutic model based on human immune cells and tumors are needed. In the present study, an immune-deficient NOG mouse with the deletion of both MHC-class I and class II genes, an MHC-double knockout mouse (dKO-NOG), was developed and used to establish humanized immunotherapeutic model. We investigated the immunological effect of the STAT3 inhibitor STX-0119 against TMZ-resistant (TMZ-R) U87 glioma tumors by using humanized dKO-NOG mice. We compared the anti-tumor effects of STX-0119 between the nude and humanized dKO-NOG mouse models. An in vivo study using the nude mouse model showed that STX-0119 inhibited the growth of TMZR U87 tumors, but accumulation of tumor-infiltrating lymphocytes (TILs) were not promoted compared with the control levels. In contrast, STX-0119 inhibited tumor growth more rapidly and strongly in humanized dKO-NOG mice than in nude mice, and a large amount of TILs, mainly consisting of CD8 + T cells and macrophages, were found in the tumors. These results suggest that STX-0119 has anti-tumor activity occurring through the promotion of TIL accumulation at the tumor site and that humanized dKO-NOG mouse system may be a powerful tool to evaluate the effects of STAT3 inhibitors on human systems. [ABSTRACT FROM AUTHOR]

New Pt(II) complexes (Pt-1-3) bearing 1,2,5-oxadiazole ligands (1-3) were synthesized, characterized and evaluated for their ability to disrupt STAT3 dimerization. Ligand 3·HCl showed cytotoxic effects on HCT-116 cells (IC50 = 95.2 μM) and a selective ability to interact with STAT3 (IC50 = 8.2 μM) versus STAT1 (IC50 > 30 μM). Its corresponding platinum complex Pt-3 exhibited an increased cytotoxicity (IC50 = 18.4 μM) and a stronger interaction with STAT3 (IC50 = 1.4 μM), leading to inhibition of its signaling pathway. Pt-3 was also evaluated in cell-based assays for its action on p53 expression and on STAT3 phosphorylation. In syngeneic murine Lewis lung carcinoma (LLC) implanted in C57BL/6 mice, Pt-3 showed a higher antitumor activity with fewer side effects than cisplatin. [ABSTRACT FROM AUTHOR]

1,3a,6a-Triazapentalene is a compact fluorescent chromophore. In this study, triazapentalene was used to modify a series of biphenyl-type inhibitors of kinesin spindle protein (KSP) to develop fluorescent probes for the intracellular visualization of this protein. Microscopic studies demonstrated that these novel triazapentalene-labeled compounds exhibited inhibitory activity towards KSP in cultured cells and provided important information concerning the intracellular distribution. [ABSTRACT FROM AUTHOR]

Abstract: Structure–activity relationship studies of diaryl amine-type KSP inhibitors were carried out. Diaryl amine derivatives with a pyridine ring or urea group were less active when compared with the parent carboline and carbazole derivatives. Optimization studies of a lactam-fused diphenylamine-type KSP inhibitor revealed that the aniline NH group and 3-CF3 phenyl group were indispensable for potent KSP inhibition. Modification with a seven-membered lactam-fused phenyl group and a 4-(trifluoromethyl)pyridin-2-yl group improved aqueous solubility while maintaining potent KSP inhibitory activity. From these studies, we identified novel diaryl amine-type KSP inhibitors with a favorable balance of potency and solubility. [Copyright &y& Elsevier]

[Display omitted] Kinesin-5 has received considerable attention as a new target for mitosis. Various small-molecule compounds targeting kinesin-5 have been developed in the last few decades. However, the differences in the cellular effects of kinesin-5 inhibitors remain poorly understood. Here, we used two different kinesin-5 inhibitors, biphenyl-type PVZB1194 and S ‐trityl‐ L ‐cysteine-type PVEI0021, to examine their effects on molecular events involving kinesin-5. Our biochemical study of kinesin-5 protein-protein interactions showed that PVZB1194-treated kinesin-5 interacted with TPX2 microtubule nucleation factor, Aurora-A kinase, receptor for hyaluronan-mediated motility, and γ-tubulin, as did untreated mitotic kinesin-5. However, PVEI0021 prevented kinesin-5 from binding to these proteins. In mitotic HeLa cells recovered from nocodazole inhibition, kinesin-5 colocalized with these binding proteins, along with microtubules nucleated near kinetochores. By acting on kinesin-5 interactions with chromatin-associated microtubules, PVZB1194, rather than PVEI0021, not only affected the formation of dispersed microtubule clusters but also enhanced the stability of microtubules. In addition, screening for mitotic inhibitors working synergistically with the kinesin-5 inhibitors revealed that paclitaxel synergistically inhibited HeLa cell proliferation only with PVZB1194. In contrast, the Aurora-A inhibitor MLN8237 exerted a synergistic anti-cell proliferation effect when combined with either inhibitor. Together, these results have provided a better understanding of the molecular action of kinesin-5 inhibitors and indicate their usefulness as molecular tools for the study of mitosis and the development of anticancer agents. [ABSTRACT FROM AUTHOR]

Abstract: Effect of CF3-STLC, a potent kinesin spindle protein (KSP) inhibitor, on K562 human CML cell line was investigated. Treatment with CF3-STLC induced mitotic arrest of the cell cycle with the appearance of characteristic monoastral spindles, subsequent apoptotic cell death and cleavage of PARP-1, caspase-3, and 4E-BP1. The wide ranging caspase inhibitor z-VAD fmk prevented the cleavage of caspase-3 and 4E-BP1, but failed to attenuate PARP-1 cleavage or cell death triggered by CF3-STLC. These results suggest that CF3-STLC can induce apoptotic cell death in a caspase-independent manner, and may work effectively as an anti-cancer agent for hematological malignancies. [ABSTRACT FROM AUTHOR]

Abstract: S-Benzylisothiourea 3a was discovered by its ability to inhibit indoleamine-2,3-dioxygenase (IDO) in our screening program. Subsequent optimization of the initial hit 3a lead to the identification of sub-μM inhibitors 3r and 10h, both of which suppressed kynurenine production in A431 cells. Synthesis and structure–activity relationship of S-benzylisothiourea analogues as small-molecule inhibitors of IDO are described. [ABSTRACT FROM AUTHOR]

Abstract: A series of boron peptides 11, 13, 15 and 17 were designed and synthesized as proteasome inhibitors based on the structure of Belactosin C. Matteson homologation was a key step in the synthesis of the boron peptides. Compounds 11a and 13 showed significant inhibition of 20S proteasome chymotrypsin-like (β5) activity (IC50 =0.28 and 0.51μM, respectively). Furthermore, like PS-341, compound 11a increased the G2/M cell distribution. A biparametric cytofluorimetric analysis with FITC-labeled annexin V and propidium iodide showed induction of apoptosis by compound 11a at >1μM concentrations of compound. [Copyright &y& Elsevier]

Abstract: Synthesis of 4-(4-tert-butylphenyl)pyridine analogues as kinesin spindle protein (KSP) inhibitors, SAR, cytotoxicity and mitotic arrest in HeLa cells are described. Interestingly, PVZB1194 showed potent KSP inhibition only in the presence of microtubules and distinct KSP localization from a known KSP inhibitor S-trytylcysteine analogue in mitosis. The observations would have resulted from a different molecular mechanism of KSP inhibition and suggest a novel biological regulation for KSP in mitosis. [Copyright &y& Elsevier]

Abstract: Several lines of evidence support the beneficial effect of tocotrienol (T3; an unsaturated vitamin E) on inhibition of tumor development. Many factors, including decrease in oxidative stress and modulation of cell signaling pathways in tumor and endothelial cells, have been implicated in such anticancer action of T3, while the in vivo potency and exact intracellular mechanisms for the anticancer properties of T3 remain not fully understood. We have hypothesized that the inhibitory effect of T3 on cancer may be attributable to the antiangiogenic activity of T3, and we found that T3 acts as a potent regulator of growth-factor-dependent signaling in endothelial cells and as an antiangiogenic agent minimizing tumor growth. In this work, we review the history and biological action (i.e., anticancer) of vitamin E and describe current research on the antiangiogenic effects of T3 and its mechanisms. [Copyright &y& Elsevier]

Abstract: Aims: The atherogenicity of chylomicron remnants has been discussed. We examined whether serum apoB48 level is associated with the presence of carotid plaque in type 2 diabetic patients. Method: Forty type 2 diabetic patients (21 males and 19 females, 52.8±11.8 years old; mean±S.D.) were divided into two groups by the presence or absence of carotid plaque. The diurnal change of serum apoB48 level was measured by enzyme-linked immunosorbent assay. Results: Fasting serum apoB48 level was higher in the subjects with carotid plaque than those without (6.5±3.8vs. 4.1±1.9μg/ml, p =0.01). Age- and gender-adjusted analysis showed that the presence of carotid plaque was associated with fasting apoB48 (OR 1.43; 95% CI, 1.07–2.09, p =0.04) and triglyceride (OR 1.14; 95% CI, 1.02–1.32, p =0.04) levels. In normal LDL-cholesterol (<140mg/dl) subjects, the presence of carotid plaque was associated with fasting apoB48 level (OR 2.16; 95% CI, 1.22–5.32, p =0.04), but not associated with fasting triglyceride level (OR 1.11; 95% CI, 0.99–1.30, p =0.13). Conclusions: Serum apoB48 level was strongly associated with the presence of carotid plaque in type 2 diabetic patients. [Copyright &y& Elsevier]

Abstract: Inhibition of Eg5 represents a novel approach for the treatment of cancer. Here, we report the synthesis and structure-activity relationship of S-trityl-l-cysteine (STLC) derivatives as Eg5 inhibitors. Some of these derivatives such as 4f demonstrated enhanced inhibitory activity against Eg5 and induced mitotic arrest with characteristic monoastral spindles in HeLa cells. [Copyright &y& Elsevier]

Abstract: The first application of a combination of novel ψ[(E)-CXalkene dipeptide isosteres to conformation studies of cyclic bioactive peptides was carried out (X=H or Me). For exploration of bioactive conformations of Kessler''s cyclic RGD peptides, cyclo(-Arg-Gly-Asp-d-Phe-Val-) 1 and cyclo(-Arg-Gly-Asp-d-Phe-N-MeVal-) 2 , d-Phe-ψ[(E)-CXmall-caps>l-Val-type dipeptide isosteres were utilized having di-, tri- and tetrasubstituted alkenes containing the γ-methylated isosteres that have been reported to be potential type II′ β-turn promoters. All of the (E)-alkene pseudopeptides 3–6 exhibited higher antagonistic potency against αvβ3 integrin than 1 , although potencies were slightly lower than 2 . Detailed structural analysis using 1H NMR spectroscopy revealed that representative type II′ β/γ backbone arrangements proposed for 1 , were not observed in peptides 3–6 . Rather on the basis of 1H NMR data, the conformations of peptides 3–6 were estimated to be more analogous to those of the N-methylated peptide 2 . [Copyright &y& Elsevier]

Novel halohydrin and oxime derivatives of radicicol (1) were prepared and evaluated for their v-src tyrosine kinase inhibitory, antiproliferative, and antitumor activities. Some of the resulting derivatives showed significantly improved antitumor activities than those of 1 in vitro as tested in a cell proliferation assay and in vivo using sc-inoculated human breast carcinoma and epidermoid tumor models. Design and synthesis of radicicol-based novel affinity probes are also described. [Copyright &y& Elsevier]

Kinesin spindle protein (KSP) is expressed only in cells undergoing cell division, and hence represents an attractive target for the treatment of cancer. Several KSP inhibitors have been developed and undergone clinical trial, but their clinical use is limited by their toxicity to rapidly proliferating non - cancerous cells. To create new KSP inhibitors that are highly selective for cancer cells, we optimized the amino acid moiety of S -trityl - l - cysteine (STLC) derivative 1 using in silico modeling. Molecular docking and molecular dynamics simulation were performed to investigate the binding mode of 1 with KSP. Consistent with the structure activity relationship studies, we found that a cysteine amino moiety plays an important role in stabilizing the interaction. Based on these findings and the structure of GSH, a substrate of γ - glutamyltransferase (GGT), we designed and synthesized the prodrug N- γ - glutamylated STLC derivative 9 , which could be hydrolyzed by GGT to produce 1. The KSP ATPase inhibitory activity of 9 was lower than that of 1 , and LC - MS analysis indicated that 9 was converted to 1 only in the presence of GGT in vitro. In addition, the cytotoxic activity of 9 was significantly attenuated in GGT - knockdown A549 cells. Since GGT is overexpressed on the cell membrane of various cancer cells, these results suggest that compound 9 could be a promising prodrug that selectively inhibits the proliferation of GGT - expressing cancer cells. [Display omitted] • A series of novel S -trityl- l -cysteine derivatives as KSP inhibitors were synthesized. • Docking studies were performed to understand the pharmacophore and add new functions. • Prodrug 9 , activated by GGT and exhibiting cytotoxicity, was designed. • The correlation between cellular GGT levels and cytotoxicity treatment with 9 was investigated. • A KSP inhibitor activated by GGT was identified as a novel prodrug. [ABSTRACT FROM AUTHOR]

Abstract: Biochemical analysis of the cellular target of S-trityl-l-cysteine (STLC) derivatives was performed by using the newly synthesized STLC derivative-immobilized affinity beads (3d). The affinity beads efficiently captured KSP in HCT116 cytoplasmic cell lysate. The results obtained from pull-down and competition experiments using 3d with STLC derivatives provided the first evidence for direct interaction of these derivatives with KSP in cancer cells. Design, synthesis and application of 3d were reported. [Copyright &y& Elsevier]