1.Determination of six polyether antibiotic residues in foods of animal origin by solid phase extraction combined with liquid chromatography-tandem mass spectrometry.
Ha J1, Song G2, Ai LF3, Li JC2. J Chromatogr B Analyt Technol Biomed Life Sci. 2016 Apr 1;1017-1018:187-94. doi: 10.1016/j.jchromb.2016.01.057. Epub 2016 Mar 2.
A new method using solid phase extraction (SPE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the determination of six polyether antibiotics, including lasalocid, salinomycin, monensin, narasin, madubamycin and nigericin residues, in foods of animal origin. The samples were extracted with acetonitrile and purified by ENVI-Carb SPE columns after comparing the impurity effect and maneuverability of several SPE cartridges. Subsequently, the analytes were separated on a Hypersil Gold column (2.1×150mm, 5μm) and analyzed by MS/MS detection. The limit of quantization (LOQ) for milk and chicken was 0.4μg/kg, and for chicken livers and eggs, it was 1μg/kg. The linearity was satisfactory with a correlation coefficient of >0.9995 at concentrations ranging from 2 to 100μg/L. The average recoveries of the analytes fortified at three levels ranged from 68.2 to 114.3%, and the relative standard deviations ranged from 4.
2.The impact of metformin and salinomycin on transforming growth factor β-induced epithelial-to-mesenchymal transition in non-small cell lung cancer cell lines.
Koeck S1, Amann A1, Huber JM1, Gamerith G1, Hilbe W2, Zwierzina H1. Oncol Lett. 2016 Apr;11(4):2946-2952. Epub 2016 Mar 9.
The epithelial-to-mesenchymal transition (EMT) is highly involved in the development of metastases. EMT transforms epithelial carcinoma cells into mesenchymal-like cells, characterized by increased cell migration and invasiveness. Transforming growth factor β (TGFβ) appears to be crucial in this process. Metformin and salinomycin have demonstrated an EMT inhibitory effect. The current experiments indicate that these substances specifically inhibit TGFβ-induced EMT in non-small cell lung cancer (NSCLC) cell lines. The NSCLC cell lines A549 and HCC4006 were stimulated with TGFβ for 48 h to induce EMT. Metformin or salinomycin was added simultaneously with TGFβ to inhibit TGFβ-induced EMT. Western blot analyses of E-cadherin and vimentin were performed to detect changes in EMT marker expression, and a wound healing assay was conducted to determine the potential effects on cell migration. The effects of the two drugs on cell viability were also investigated using MTS tetrazolium dye assays.
3.Salinomycin causes migration and invasion of human fibrosarcoma cells by inducing MMP-2 expression via PI3-kinase, ERK-1/2 and p38 kinase pathways.
Yu SM1, Kim SJ1. Int J Oncol. 2016 Mar 22. doi: 10.3892/ijo.2016.3448. [Epub ahead of print]
Salinomycin (SAL) is a polyether ionophore antibiotic that has recently been shown to regulate a variety of cellular responses in various human cancer cells. However, the effects of SAL on metastatic capacity of HT1080 human fibrosarcoma cells have not been elucidated. We investigated the effect of SAL on migration and invasion, with emphasis on the expression and activation of matrix metalloproteinase (MMP)-2 in HT1080 human fibrosarcoma cells. Treatment of SAL promoted the expression and activation of MMP-2 in a dose- and time-dependent manner, as detected by western blot analysis, gelatin zymography, and real-time polymerase chain reaction. SAL also increased metastatic capacities, as determined by an increase in the migration and invasion of cells using the wound healing assay and the invasion assay, respectively. To confirm the detailed molecular mechanisms of these effects, we measured the activation of phosphoinositide 3 kinase (PI3-kinase) and mitogen-activated protein kinase (MAPK)s (ERK-1/2 and p38 kinase), as detected by the phosphorylated proteins through western blot analysis.
4.CD44 targeted chemotherapy for co-eradication of breast cancer stem cells and cancer cells using polymeric nanoparticles of salinomycin and paclitaxel.
Muntimadugu E1, Kumar R2, Saladi S3, Rafeeqi TA4, Khan W5. Colloids Surf B Biointerfaces. 2016 Mar 26;143:532-546. doi: 10.1016/j.colsurfb.2016.03.075. [Epub ahead of print]
This combinational therapy is mainly aimed for complete eradication of tumor by killing both cancer cells and cancer stem cells. Salinomycin (SLM) was targeted towards cancer stem cells whereas paclitaxel (PTX) was used to kill cancer cells. Drug loaded poly (lactic-co-glycolic acid) nanoparticles were prepared by emulsion solvent diffusion method using cationic stabilizer. Size of the nanoparticles (below 150nm) was determined by dynamic light scattering technique and transmission electron microscopy. In vitro release study confirmed the sustained release pattern of SLM and PTX from nanoparticles more than a month. Cytotoxicity studies on MCF-7 cells revealed the toxicity potential of nanoparticles over drug solutions. Hyaluronic acid (HA) was coated onto the surface of SLM nanoparticles for targeting CD44 receptors over expressed on cancer stem cells and they showed the highest cytotoxicity with minimum IC50 on breast cancer cells. Synergistic cytotoxic effect was also observed with combination of nanoparticles.