Cardiotoxin III inhibits proliferation and migration of oral cancer cells through MAPK and MMP signaling.

Cardiotoxin III (CTXIII), isolated from the snake venom of Formosan cobra Naja naja atra, has previously been found to induce apoptosis in many types of cancer. Early metastasis is typical for the progression of oral cancer. To modulate the cell migration behavior of oral cancer is one of the oral cancer therapies. In this study, the possible modulating effect of CTXIII on oral cancer migration is addressed. In the example of oral squamous carcinoma Ca9-22 cells, the cell viability was decreased by CTXIII treatment in a dose-responsive manner. In wound-healing assay, the cell migration of Ca9-22 cells was attenuated by CTXIII in a dose- and time-responsive manner. After CTXIII treatment, the MMP-2 and MMP-9 protein expressions were downregulated, and the phosphorylation of JNK and p38-MAPK was increased independent of ERK phosphorylation. In conclusion, CTXIII has antiproliferative and -migrating effects on oral cancer cells involving the p38-MAPK and MMP-2/-9 pathways.

Functional fluorinated modifications on a polyelectrolyte coated polydimethylsiloxane substrate for fabricating antibody microarrays.

Fluorinated compounds exhibit hydrophobic, nonstick, and self-cleaning properties, making them attractive for use as the coating material for biochips. In this study, we copolymerized the fluorinated compound 1H,1H,2H-perfluoro-1-decene (FD) with acrylic acid (AA) and bonded the resulting copolymer with protein G on the surface of polyelectrolyte coated polydimethylsiloxane (PDMS) to form a functional surface that captures antibodies. We demonstrated that the modified PDMS surface remained hydrophobic while becoming resistant to nonspecific protein binding. Thus, aqueous sample solutions formed the droplets (4 µL) on the surface without spreading and drying during the sample printing. Contact angle measurements showed that this functionalized surface was as hydrophobic as the native PDMS with a virtually constant contact angle over seven days of the study under dried condition at 4 °C. Spectroscopic measurements revealed that FD/AA copolymerization formed a homogeneous and highly dense multilayer (50 mg/mm(2)) with a fluorine coverage of 35.4%. Moreover, protein G was shown to covalently bind to AA molecules on the surface at a binding density of 0.24 µg/mm(2). We demonstrated that the fluorinated coating withstood nonspecific binding with extremely low background emission, leading to bioassays that, without the need of blocking agents, exhibited six times more sensitivity than PEG coatings. The fluorinated PDMS antibody microarrays were further applied to accurately determine the absolute concentration of ERα in MCF-7 cells. In conclusion, the unique properties of fluorinated compounds, such as withstanding wetting, nonspecific binding and contamination, make them an excellent coating material for use in sensitive and simple on-chip assays.

Fabrication of Biodegradable Poly(caprolactone) Spherical-Microcarriers for Arterial Embolization.

This study aimed to develop emulsification assisted with ultrasonic atomization (EUA) to make embolic biodegradable poly(caprolactone) (PCL) spherical-microcarriers with uniform particle size for mass production which was used to cure hepatocellular carcinoma, because this kind of embolic drugs is expensive at the current market due to their complex manufacturing process. The embolic spherical-microcarriers with sustained-releasing therapeutic agents can shrink an unresectable tumor into a respectable size. Through high frequency vibrating surface on the ultrasonic atomizer nozzle, the thin liquid film for PCL oil-phase solution was broken into the uniform PCL microdroplets (particle sizes are from 20 to 55 µm) with less medicine loss. To determine the optimal parameters to make PCL microcarriers, the ultrasonic module parameters including the concentration of PCL solution, vibrating amplitude of atomizer, feeding rate of PCL oil-phase solution and collection distance on the particle size of microdroplets were analyzed. Besides, a vertical circulation flow field of aqueous-phase poly(vinyl alcohol) (PVA) solution was created to enhance the separation of the microdroplets and increase the production of the PCL microcarriers, and about 8~11 wt% of PVA solution with high stable dispersion property was used to effectively improve the yield rate of PCL spherical-microcarriers (89.8~98.2 wt%). The final particle size of PCL microcarriers was ca. 5-18 µm, indicating an about 25-50% volume shrinkage from microdroplets to solid spherical-microcarriers.

The Impact of Di(2-ethylhexyl)phthalate on Cancer Progression.

Di(2-ethylhexyl)phthalate (DEHP), a widely used plasticizer, mainly serves as an additive to render polyvinyl chloride (PVC) soft and flexible. PVC plastics have become ubiquitous in our modern society. Yet, the leaching of DEHP from PVC-based consumables ultimately results in the deposition in certain tissues via inadvertent applications. Health risks for human populations exposed to DEHP has been assumed by studies on rodents and other species, including the DEHP-induced developmental dysregulation, reproductive impairments, tumorigenesis, and diseases in a transgenerational manner. In this review, we comprehensively summarize the accumulated literature regarding the multifaceted roles of DEHP in the activation of the nuclear receptors, the alteration of the redox homeostasis, epigenetic modifications and the acquisition of chemoresistance.

Diverse macroporous spheres synthesized by multiple emulsion polymerization for protein analyses.

Hydrophilic and hydrophobic spheres (1-2 mm) with macropores (50 µm) were synthesized by SDS stabilized O/W/O and W/O/W emulsion polymerization, respectively. The hydrophilic spheres were functionalized with trypsin for protein digestion and on-line integrated with the hydrophobic spheres for the subsequent sample clean-up and enrichment with almost no back pressure.

Monolithic microextraction tips by emulsion photopolymerization.

Monoliths formed by photopolymerization are excellent means for fabricating functional elements in miniaturized microdevices such as microextraction tips which are becoming important for sample preparation. Various silica-based and polymer-based materials have been used to fabricate monoliths with through pores of several nm to 4 microm. However, the back pressure created by such methods is still considered to be high for microtips that use suction forces to deliver the liquid. In this study, we demonstrated that emulsion techniques such as oil-in-water can be used to form monoliths with large through pores (>20 microm), and with rigid structures on small (10 microL) and large (200 microL) pipette tips by photopolymerization. We further showed that, with minor modifications, various functionalized particles (5-20 microm) can be added to form stable emulsions and successfully encapsulated into the monoliths for qualitative and quantitative solid-phase microextractions for a diverse application. Due to high permeability and large surface area, quick equilibration can be achieved by pipetting to yield high recovery rates. Using tryptic digests of ovalbumin as the standard, we obtained a recovery yield of 90-109% (RSD: 10-16%) with a loading capacity of 3 mug for desalting tips immobilized with C18 beads. Using tryptic digests of beta-casein and alpha-casein as standards, we showed that phosphopeptides were substantially enriched by tips immobilized with immobilized metal affinity chromatography or TiO(2) materials. Using estrogenic compounds as standards, we obtained a recovery yield of 95-108% (RSD: 10-12%) and linear calibration curves ranging from 5 to 100 ng (R(2)>0.99) for Waters Oasis HLB tips immobilized with hydrophilic beads.

Photopolymerized microtips for sample preparation in proteomic analysis.

We demonstrate a novel method for the fabrication of disposable plastic microtips, which we name "EasyTip", by a photopolymerization technique. C18 reversed-phase (C18) and ion metal affinity chromatography (IMAC) beads were immobilized on a plastic pipette tip, made of polypropylene materials, by photo-initiated polymerization. The fabricated EasyTips can be manipulated using commercial pipettes for wash/elution of minute amount of biological samples (< 10 microL) and can be applied for mass spectrometry (MS)-based proteomic analysis, in which the detection sensitivity depends critically on the optimal sample preparation. The recovery of a sample of 25 fmol of tryptic hemoglobin digest loaded in a C18 EasyTip was near 100% and we estimated the loading capacity to be around 0.4-2.0 microg of total proteins or peptides, which is well above a sufficient quantity for MS analysis. The effectiveness of the C18 EasyTips in enhancing the detection sensitivity of matrix-assisted laser desorption/ionization (MALDI)-MS signal, and thus providing a greater sequence coverage, was also demonstrated by the analysis of hemoglobin digest and the in-gel digested epidermal growth factor receptor (EGFR) protein from A431 cell lysate. We also demonstrated the usefulness of the immobilized IMAC EasyTips in extracting the signal of tryptic phosphopeptides of beta-casein (10 pmol) having one and four phosphorylation sites by using an IMAC EasyTip prior to off-line analysis by MS. The combination of IMAC EasyTips and MALDI-MS allowed the unambiguous identification of phosphopeptides based on the phosphatase assay as well as the post-source decay. Compared to other miniaturized devices, this fabrication method is simple, cheap, and requires less human intervention. Moreover, the method of manipulating the EasyTips is straightforward and can be automated readily by a robotic system for high-throughput analysis.