Magnetophoretic separation ICP-MS immunoassay using Cs-doped multicore magnetic nanoparticles for the determination of salmonella typhimurium.

In this work, a magnetophoretic separation ICP-MS immunoassay using newly synthesized multicore magnetic nanoparticles (MMNPs) was developed for the determination of salmonella typhimurium (typhi). The uniqueness of this method was the use of MMNPs doped with Cs for both separation and detection, which enable us to achieve fast analysis, high sensitivity, and good reliability. For demonstration, heat-killed typhi in a phosphate buffer solution was determined by ICP-MS after the MMNP-typhi reaction product was separated from unreacted MMNPs in a micropipette tip filled with 25% polyethylene glycol through magnetophoretic separation. The calibration curve obtained by plotting 133Cs intensity vs. the number of synthetic standard, showed a coefficient of determination (R2) of 0.94 with a limit of detection (LOD) of 102 cells/mL without cell culturing. Excellent recoveries, between 98-100%, were obtained from four replicates and compared with a sandwich-type ICP-MS immunoassay for further confirmation.

Reactive oxygen species dependent phosphorylation of the liver kinase B1/AMP activated protein kinase/ acetyl-CoA carboxylase signaling is critically involved in apoptotic effect of lambertianic acid in hepatocellular carcinoma cells.

Though lambertianic acid (LA) is reported to have hypolipidemic activity in liver, its underlying anticancer mechanism is poorly understood so far. Thus, in the present study, apoptotic mechanism of LA was elucidated in HepG2 and SK-Hep1 hepatocellular carcinoma (HCC) cells. Here LA increased cytotoxicity, sub-G1 population and Annexin V/PI positive cells in two HCC cells. Also, LA cleaved caspase-3 and poly(ADP-ribose) polymerase (PARP), activated phosphorylation of liver kinase B1 (LKB1)/AMP activated protein kinase (AMPK)/ acetyl-CoA carboxylase (ACC) pathway and also suppressed antiapoptotic proteins such as phosphorylation of Akt/ mammalian target of rapamycin (mTOR) and the expression of B cell lymphoma-2 (Bcl-2)/ B-cell lymphoma-extra large (Bcl-xL) and cyclooxygenase-2 (COX-2) in two HCC cells. Furthermore, LA generated reactive oxygen species (ROS) in HepG2 cells and AMPK inhibitor compound C or ROS inhibitor N-acetyl-L-cysteine (NAC) blocked the apoptotic ability of LA to cleave PARP or increase sub G1 population in HepG2 cells. Consistently, cleavages of PARP and caspase-3 were induced by LA only in AMPK+/+ MEF cells, but not in AMPK-/- MEF cells. Also, immunoprecipitation (IP) revealed that phosphorylation of LKB1/AMPK through their binding was enhanced in LA treated HepG2 cells. Overall, these findings suggest that ROS dependent phosphorylation of LKB1/AMPK/ACC signaling is critically involved in LA induced apoptosis in HCCs.

Inhibition of Myeloid Cell Leukemia 1 and Activation of Caspases Are Critically Involved in Gallotannin-induced Apoptosis in Prostate Cancer Cells.

Although gallotannin contained in several medicinal plants was known to have multi-biological activities, such as antioxidant, antiinflammatory, antimicrobial, immunomodulatory, and antitumor effects, the underlying apoptotic mechanism of gallotannin is not fully understood so far. Thus, in the present study, the apoptotic mechanism of gallotannin was elucidated in DU145, PC-3, and M2182 prostate cancer cells in association with myeloid cell leukemia 1 (Mcl-1) signaling. Gallotannin exerted dose-dependent cytotoxicity in DU145, PC-3, and M2182 prostate cancer cells. Also, gallotannin showed apoptotic morphological features and increased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling positive cells and sub-G1 accumulation in three prostate cancer cell lines. Consistently, gallotannin cleaved poly (ADP-ribose) polymerase (PARP) and attenuated the expression of procaspases 9 and 3 in three prostate cancer cell lines. Furthermore, gallotannin attenuated the expression of survival genes such as Mcl-1, B-cell lymphoma 2, and B-cell lymphoma 2 extra large in three prostate cancer cell lines. Interestingly, overexpression of Mcl-1 reversed the ability of gallotannin to cleave PARP and increase sub-G1 population in three prostate cancer cell lines. Conversely, silencing of Mcl-1 enhanced apoptosis by gallotannin in three prostate cancer cell lines by FACSCalibur (Becton Dickinson, Franklin Lakes, NJ, USA). Taken together, our findings demonstrate that inhibition of Mcl-1 and activation of caspases are critically involved in gallotannin-induced apoptosis in prostate cancer cells.

Compound K inhibits basic fibroblast growth factor-induced angiogenesis via regulation of p38 mitogen activated protein kinase and AKT in human umbilical vein endothelial cells.

Compound K (CK; 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol), an active ginseng saponin metabolite, exerts anticancer activity via apoptosis induction in various cancers. In the present study, we investigated the anti-angiogenic activity of CK and its molecular mechanisms in human umbilical vein endothelial cells (HUVECs). Angiogenesis was induced in HUVECS by basic fibroblast growth factor (bFGF), a potent angiogenic growth factor. CK significantly inhibited the proliferation and also attenuated the expression of a proliferating protein cyclin D1 in bFGF treated HUVECs. Also, CK significantly inhibited the migration and tube formation of bFGF treated HUVECs at non-cytotoxic concentrations, reduced secreted level of vascular endothelial growth factor (VEGF) and increased the secreted level of pigment epithelium-derived factor (PEDF) in HUVECs. In addition, CK effectively disrupted bFGF-induced neo-vascularization in the Matrigel plugs excised from mice in vivo. Notably, we have found that CK downregulated the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and AKT in bFGF treated HUVECs. Taken together, our findings for the first time indicate that CK exerts anti-angiogenic activity via inhibition of p38 MAPK and AKT in HUVECs with the potential of a cancer chemopreventive agent.