Synergistic effect of phosphodiesterase 4 inhibitor and serum on migration of endotoxin-stimulated macrophages.

Macrophage migration is an essential step in host defense against infection and wound healing. Elevation of cAMP by inhibiting phosphodiesterase 4 (PDE4), enzymes that specifically degrade cAMP, is known to suppress various inflammatory responses in activated macrophages, but the role of PDE4 in macrophage migration is poorly understood. Here we show that the migration of Raw 264.7 macrophages stimulated with LPS was markedly and dose-dependently induced by the PDE4 inhibitor rolipram as assessed by scratch wound healing assay. Additionally, this response required the involvement of serum in the culture medium as serum starvation abrogated the effect. Further analysis revealed that rolipram and serum exhibited synergistic effect on the migration, and the influence of serum was independent of PDE4 mRNA expression in LPS-stimulated macrophages. Moreover, the enhanced migration by rolipram was mediated by activating cAMP/exchange proteins directly activated by cAMP (Epac) signaling, presumably via interaction with LPS/TLR4 signaling with the participation of unknown serum components. These results suggest that PDE4 inhibitors, together with serum components, may serve as positive regulators of macrophage recruitment for more efficient pathogen clearance and wound repair

Design, synthesis, cytotoxic activity and molecular docking studies of new 20(S)-sulfonylamidine camptothecin derivatives

20(S)-Sulfonylamidine CPT-derivatives were prepared and tested for cytotoxicity.Several analogs showed superior cytotoxic activity compared to irinotecan.Key structural features related to cytotoxicity were identified by SAR analysis.Compounds 9 and 15c interacted with Topo I-DNA by a different binding mode from CPT.These compounds are new generation CPT-derived antitumor agents.In an ongoing investigation of 20-sulfonylamidine derivatives (9, YQL-9a) of camptothecin (1) as potential anticancer agents directly and selectively inhibiting topoisomerase (Topo) I, the sulfonylamidine pharmacophore was held constant, and a camptothecin derivatives with various substitution patterns were synthesized. The new compounds were evaluated for antiproliferative activity against three human tumor cell lines, A-549, KB, and multidrug resistant (MDR) KB subline (KBvin). Several analogs showed comparable or superior antiproliferative activity compared to the clinically prescribed 1 and irinotecan (3). Significantly, the 20-sulfonylamidine derivatives exhibited comparable cytotoxicity against KBvin, while 1 and 3 were less active against this cell line. Among them, compound 15c displayed much better cytotoxic activity than the controls 1, 3, and 9. Novel key structural features related to the antiproliferative activities were identified by structure–activity relationship (SAR) analysis. In a molecular docking model, compounds 9 and 15c interacted with Topo I-DNA through a different binding mode from 1 and 3. The sulfonylamidine side chains of 9 and 15c could likely form direct hydrogen bonds with Topo I, while hydrophobic interaction with Topo I and π–π stacking with double strand DNA were also confirmed as binding driving forces. The results from docking models were consistent with the SAR conclusions. The introduction of bulky substituents at the 20-position contributed to the altered binding mode of the compound by allowing them to form new interactions with Topo I residues. The information obtained in this study will be helpful for the design of new derivatives of 1 with most promising anticancer activity.CPT (green), 9 (magenta), and 15c (blue) in the binding site of DNA-Topo-I

Synthesis of novel spin-labeled derivatives of 5-FU as potential antineoplastic agents

Chemotherapy is a general treatment option for various cancers, including lung cancer. In order to find compounds with superior bioactivity and less toxicity against lung cancer, novel spin-labeled 5-fluorouracil (5-FU) derivatives (3a–f) were synthesized and evaluated against four human tumor cell lines (A-549, DU-145, KB, and KBvin). Two promising compounds 3d and 3f exhibited IC50 values of 2.76 and 2.38 μM, respectively, against non-small cell lung carcinoma cell line A-549. These compounds were twofold more cytotoxic than 5-FU and less toxic against other tested cell lines. Compound 3f exhibited seven times more selective cytotoxicity against A-549 than 5-FU. Our results suggest that compounds 3d and 3f merit further investigation for development into clinical trial candidates for non-small cell lung cancer

Is impaired energy regulation the core of the metabolic syndrome in various ethnic groups of the USA and Taiwan?

<p>Abstract</p> <p>Background</p> <p>The metabolic syndrome (MetS) concept is widely used in public health and clinical settings without an agreed pathophysiology. We have re-examined the MetS in terms of body fuels, so as to provide a coherent cross-cultural pathogenesis.</p> <p>Methods</p> <p>National Health and Nutrition Examination Survey (NHANES 2001-2) with n = 2254 and Taiwanese National Health Interview Survey (NHIS) sub-set for hypertension, hyperglycemia and hyperlipidemia assessment (TwSHHH 2002), n = 5786, were used to compare different ethnicities according to NCEP-ATPIII (NCEP-tw) criteria for METS. Exploratory factor analysis (EFA) using principal components (PC) was employed to differentiate and unify MetS components across four ethnicities, gender, age-strata, and urban-rural settings.</p> <p>Results</p> <p>The first two factors from the PC analysis (PCA) accounted for from 55.2% (non-Hispanic white) to 63.7% (Taiwanese) of the variance. Rotated factor loadings showed that the six MetS components provided three clusters: the impaired energy regulation (IER) components (waist circumference, WC, fasting triglycerides, TG, and fasting plasma glucose, FPG), systolic and diastolic blood pressures (BPs), and HDL-cholesterol, where the IER components accounted for 25-26% of total variance of MetS components. For the three US ethnic subgroups, factor 1 was mainly determined by IER and HDL-cholesterol, and factor 2 was related to the BP components. For Taiwanese, IER was determinant for both factors, and BPs and HDL-cholesterol were related to factors 1 and 2 respectively.</p> <p>Conclusions</p> <p>There is a MetS core which unifies populations. It comprises WC, TG and FPG as a core, IER, which may be expressed and modulated in various second order ways.</p

Analysis of Epitopes on Dengue Virus Envelope Protein Recognized by Monoclonal Antibodies and Polyclonal Human Sera by a High Throughput Assay

Dengue virus is the leading cause of arboviral diseases worldwide. The envelope protein is the major target of neutralizing antibodies and vaccine development. While previous studies have reported several epitopes on envelope protein, the possibility of interdomain epitopes and the relationship of epitopes to neutralizing potency remain unexplored. We developed a high throughput dot blot assay by using 67 alanine mutants of surface-exposed envelope residues as a systematic approach to identify epitopes recognized by mouse monoclonal antibodies and polyclonal human sera. Our results suggested the presence of interdomain epitopes more frequent than previously appreciated. Compared with monoclonal antibodies generated by traditional protocol, the potent neutralizing monoclonal antibodies generated by a new protocol showed several unique features of their epitopes. Moreover, the predominant epitopes of antibodies against envelope protein in polyclonal sera can be identified by this assay. These findings have implications for future development of epitope-specific diagnostics and epitope-based dengue vaccine, and add to our understanding of humoral immune responses to dengue virus at the epitope level

Design, Synthesis, Mechanisms of Action, and Toxicity of Novel 20( S )-Sulfonylamidine Derivatives of Camptothecin as Potent Antitumor Agents

Twelve novel 20-sulfonylamidine derivatives (9a–9l) of camptothecin (1) were synthesized via a Cu-catalyzed three-component reaction. They showed similar or superior cytotoxicity compared with that of irinotecan (3) against A-549, DU-145, KB, and multidrug-resistant (MDR) KBvin tumor cell lines. Compound 9a demonstrated better cytotoxicity against MDR cells compared with that of 1 and 3. Mechanistically, 9a induced significant DNA damage by selectively inhibiting Topoisomerase (Topo) I and activating the ATM/Chk related DNA damage-response pathway. In xenograft models, 9a demonstrated significant activity without overt adverse effects at 5 and 10 mg/kg, comparable to 3 at 100 mg/kg. Notably, 9a at 300 mg/kg (i.p.) showed no overt toxicity in contrast to 1 (LD50 56.2 mg/kg, i.p.) and 3 (LD50 177.5 mg/kg, i.p.). Intact 9a inhibited Topo I activity in a cell-free assay in a manner similar to that of 1, confirming that 9a is a new class of Topo I inhibitor. 20-Sulfonylamidine 1-derivative 9a merits development as an anticancer clinical trial candidate

The 5p15.33 Locus Is Associated with Risk of Lung Adenocarcinoma in Never-Smoking Females in Asia

Genome-wide association studies of lung cancer reported in populations of European background have identified three regions on chromosomes 5p15.33, 6p21.33, and 15q25 that have achieved genome-wide significance with p-values of 10−7 or lower. These studies have been performed primarily in cigarette smokers, raising the possibility that the observed associations could be related to tobacco use, lung carcinogenesis, or both. Since most women in Asia do not smoke, we conducted a genome-wide association study of lung adenocarcinoma in never-smoking females (584 cases, 585 controls) among Han Chinese in Taiwan and found that the most significant association was for rs2736100 on chromosome 5p15.33 (p = 1.30×10−11). This finding was independently replicated in seven studies from East Asia totaling 1,164 lung adenocarcinomas and 1,736 controls (p = 5.38×10−11). A pooled analysis achieved genome-wide significance for rs2736100. This SNP marker localizes to the CLPTM1L-TERT locus on chromosome 5p15.33 (p = 2.60×10−20, allelic risk = 1.54, 95% Confidence Interval (CI) 1.41–1.68). Risks for heterozygote and homozygote carriers of the minor allele were 1.62 (95% CI; 1.40–1.87), and 2.35 (95% CI: 1.95–2.83), respectively. In summary, our results show that genetic variation in the CLPTM1L-TERT locus of chromosome 5p15.33 is directly associated with the risk of lung cancer, most notably adenocarcinoma