Gene expression analysis of primary gingival cancer by whole exome sequencing in thirteen Chinese patients.

OBJECTIVES: Early diagnosis of and markers for gingival oral squamous cell carcinoma (OSCC) is important for effective treatment. METHODS: The current study performed a whole exome sequencing of gingival OSCC tissues in thirteen Chinese patients to explore exonic mutants. RESULTS: Eighty-five genes emerged as mutants in patients with primary gingival OSCC. CCL4L1 presented a G>A transversion at chr17 17q12, position 36212480, exon 3. KDM5B presented a T>TA insertion at chr1 1q32.1, position 202766506, exon 6. ANKRD36C presented a C>G transition at chr2 2q11.1, position 95945175, exon 18. CONCLUSION: These three mutants might be new markers of gingival OSCC. The finding may provide new targets to diagnose and treat gingival OSCC.

The immobilization of proteins on biodegradable polymer fibers via click chemistry.

A facile and efficient method to immobilize bioactive proteins onto polymeric substrate was established. Testis-specific protease 50 (TSP50) was immobilized on ultrafine biodegradable polymer fibers, i.e., (1) to prepare a propargyl-containing polymer P(LA90-co-MPC10) by introducing propargyl group into a cyclic carbonate monomer (5-methyl-5-propargyloxycarbonyl-1,3-dioxan-2-one, MPC) and copolymerizing it with l-lactide; (2) to electrospin the functionalized polymer into ultrafine fibers; (3) to azidize the TSP50, and (4) to perform the click reaction between the propargyl groups on the fibers and the azido groups on the protein. The TSP50-immobilized fibers can resist non-specific protein adsorptions but preserve specific recognition and combination with anti-TSP50. ELISA tests were carried out by using HRP-goat-anti-mouse-IgG(H+L) as secondary antibody and o-phenylenediamine (OPDA)/H(2)O(2) as substrate to detect the combination of immobilized TSP50 with anti-TSP50. The results showed that anti-TSP50 can be selectively adsorbed from its solution onto the TSP50-immobilized fibers in the presence of BSA of as high as 10(4) times concentration. TSP50 immobilized on the fiber and anti-TSP50 combined to the fiber were also quantitatively determined. Anti-TSP50 can be then eluted off from the fiber when pH changes. The eluted fiber can re-combine anti-TSP50 at an efficiency of 75% compared to the original TSP50-immobilized fiber. Therefore, the TSP50-immobilized fibers can be used in the detection, separation, and purification of anti-TSP50. The "click" method can lead to a universal strategy to protein immobilization.

Fabrication of biodegradable electrospun poly(L-lactide-co-glycolide) fibers with antimicrobial nanosilver particles.

Biodegradable poly(lactide-co-glycolide) (PLGA) antimicrobial nanofibers containing silver nanoparticles were prepared by electrospinning technique. Characterization of the Ag/PLGA nanofiber mats were determined by using SEM, TEM, WAXD and UV-vis spectrum. The antibacterial efficacy of the composites mats made of silver nanoparticles and PLGA fibers was measured. The antimicroorganization efficacy of Ag nanoparticles along with the biodegradability of the PLGA fibers can be combined in practical medical applications.

BCNU-loaded PEG-PLLA ultrafine fibers and their in vitro antitumor activity against Glioma C6 cells.

The purpose of the present study was to develop implantable BCNU-loaded poly(ethylene glycol)-poly(L-lactic acid) (PEG-PLLA) diblock copolymer fibers for the controlled release of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). BCNU was well incorporated and dispersed uniformly in biodegradable PEG-PLLA fibers by using electrospinning method. Environmental Scanning Electron Microscope (ESEM) images indicated that the BCNU-loaded PEG-PLLA fibers looked uniform and their surfaces were reasonably smooth. Their average diameters were below 1500 nm. The release rate of BCNU from the fiber mats increased with the increase of BCNU loading amount. In vitro cytotoxicity assay showed that the PEG-PLLA fibers themselves did not affect the growth of rat Glioma C6 cells. Antitumor activity of the BCNU-loaded fibers against the cells was kept over the whole experiment process, while that of pristine BCNU disappeared within 48 h. These results strongly suggest that the BCNU/PEG-PLLA fibers have an effect of controlled release of BCNU and are suitable for postoperative chemotherapy of cancers.

The FPase properties and morphology changes of a cellulolytic bacterium, Sporocytophaga sp. JL-01, on decomposing filter paper cellulose.

Sporocytophaga sp. JL-01 is a sliding cellulose degrading bacterium that can decompose filter paper (FP), carboxymethyl cellulose (CMC) and cellulose CF11. In this paper, the morphological characteristics of S. sp. JL-01 growing in FP liquid medium was studied by Scanning Electron Microscope (SEM), and one of the FPase components of this bacterium was analyzed. The results showed that the cell shapes were variable during the process of filter paper cellulose decomposition and the rod shape might be connected with filter paper decomposing. After incubating for 120 h, the filter paper was decomposed significantly, and it was degraded absolutely within 144 h. An FPase1 was purified from the supernatant and its characteristics were analyzed. The molecular weight of the FPase1 was 55 kDa. The optimum pH was pH 7.2 and optimum temperature was 50°C under experiment conditions. Zn(2+) and Co(2+) enhanced the enzyme activity, but Fe(3+) inhibited it.

Folate-conjugated micelles and their folate-receptor-mediated endocytosis.

A folate-conjugated copolymer PEG-PLA-PLL/folate was synthesized and mixed with pure PEG-PLA-PLL and a fluorescent model drug mFITC to prepare folate-conjugated micelles. The distribution of micelles was studied on cancer-cell-bearing mice via frozen slicing. The results show that mFITC is successfully encapsulated into folate(+) and folate(-)micelles; PEG-PLA-PLL micelles the latter can be internalized by both HeLa and CHO cells without selectivity due to their cationic surface charges, while folate(+)micelles exhibit more preferential endocytosis by HeLa cells than by CHO cells. The folate(-)micelles showed retention in both organs and tumors. The folate(+)micelles are a promising active targeting drug delivery system for FR over-expressing cells and they accumulate in tumor beds.

Synthesis, self-assembly in water, and cytotoxicity of MPEG-block-PLLA/DX conjugates.

Docetaxel (DX) is one of the most effective antineoplastic drugs. Its current clinical administration is limited because of its hydrophobicity and serious side effects. A polymer/DX conjugate is designed and successfully prepared to solve these problems. It is monomethoxy-poly(ethylene glycol)-block-poly(L-lactide)/DX (MPEG-PLLA/DX). It was synthesized by reacting DX with carboxyl-terminated copolymer MPEG-PLLA, which was prepared by reacting succinic anhydride with hydroxyl-terminated copolymer monomethoxy-poly(ethylene glycol)-block-poly(L-lactide) (MPEG-PLLA). Its structure and molecular weight was confirmed by (1)H NMR and GPC. The MPEG-PLLA/DX micelles in aqueous solution were prepared using a solvent displacement method and characterized by dynamic light scattering for size and size distribution, and by transmission electron microscopy for surface morphology. Its antitumor activity against HeLa cancer cells evaluated by MTT assay showed that it had a similar antitumor activity to pure DX at the same drug content.

Formation of reversible shell cross-linked micelles from the biodegradable amphiphilic diblock copolymer poly(L-cysteine)-block-poly(L-lactide).

A novel biodegradable diblock copolymer, poly(L-cysteine)-b-poly(L-lactide) (PLC-b-PLLA), was synthesized by ring-opening polymerization (ROP) of N-carboxyanhydride of beta-benzyloxycarbonyl-L-cysteine (ZLC-NCA) with amino-terminated poly(L-lactide) (NH 2-PLLA) as a macroinitiator in a convenient way. The diblock copolymer and its precursor were characterized by (1)H NMR, Fourier transform infrared (FT-IR), gel permeation chromatography (GPC), and X-ray photoelectron spectroscopy (XPS) measurements. The length of each block polymer could be tailored by molecular design and the ratios of feeding monomers. The cell adhesion and cell spread on the PZLC-b-PLLA and PLC-b-PLLA films were enhanced compared to those on pure PLA film. PLC-b-PLLA can self-assemble to form micelles in aqueous media. A pyrene probe is used to demonstrate the micelle formation of PLC-b-PLLA in aqueous solution. Due to the ease of disulfide exchange with thiols, the obtained micelles are reversible shell cross-linked (SCL) micelles. The morphology and size of the micelles are studied by dynamic light scattering (DLS) and environmental scanning electron microscopy (ESEM).

The immobilization of proteins on biodegradable fibers via biotin-streptavidin bridges.

This paper aims at developing novel bioactive fibrous mats for protein immobilization and for protein separation/purification. For this purpose, an amphiphilic triblock copolymer, biotinylated poly(ethylene glycol)-b-poly(L-lactide)-b-poly(L-lysine) was co-electrospun together with poly(L-lactide-co-glycolide) into ultrafine fibers approximately 2 microm in diameter, and a layer of blocking agent was coated on the fiber surfaces to block off possible non-specific binding of proteins. The biotin species retained their ability to specifically recognize and bind streptavidin, and the immobilized streptavidin could further combine with biotinylated antibodies, antigens and other biological moieties. Horseradish peroxidase-labeled streptavidin and fluorescein isothiocyanate-labeled goat globulin were used to detect the immobilizations of streptavidin and rabbit anti-goat IgG(H+L) via enzyme-linked immunoassay and confocal laser scanning microscope, respectively. The immobilized antigen was eluted from the fiber substrate with a glycine/HCl solution and the eluted antigen retained its bioactivity. Therefore, these biotin-carrying composite fibers have a variety of uses, including selective immobilization of functional proteins, antigen/antibody separation and purification, and vaccine preparation.

Biodegradable amphiphilic triblock copolymer bearing pendant glucose residues: preparation and specific interaction with Concanavalin A molecules.

A novel biodegradable amphiphilic block copolymer PLGG-PEG-PLGG bearing pendant glucose residues is successfully prepared by the coupling reaction of 3-(2-aminoethylthio)propyl-alpha-D-glucopyranoside with the pendant carboxyl groups of PLGG-PEG-PLGG in the presence of N,N'-carbonyldiimidazole. The polymer PLGG-PEG-PLGG, i.e., poly{(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}-block-poly(ethylene glycol)-block- poly{(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}, is prepared by ring-opening copolymerization of L-lactide (LLA) with (3s)-benzoxylcarbonylethylmorpholine-2,5-dione (BEMD) in the presence of dihydroxyl PEG with molecular weight of 2000 as macroinitiator and Sn(Oct)2 as catalyst, and then by catalytic hydrogenation. The glucose-grafted copolymer shows a lower degree of cytotoxicity to ECV-304 cells and improved specific recognition and binding with Concanavalin A (Con A). Therefore, this kind of glucose-grafted copolymer may find biomedical applications.