Radiofrequency-induced hyperthermia (HT) treatments for cancer include conventional capacitive coupling hyperthermia (cCHT) and modulated electro-hyperthermia (mEHT). In this study, we directly compared these methods with regard to in vitro cytotoxicity and mechanisms of action under isothermal conditions. Hepatoma (HepG2) cells were exposed to HT treatment (42°C for 30 min) using mEHT, cCHT or a water bath. mEHT produced a much higher apoptosis rate (43.1% ± 5.8%) than cCHT (10.0% ± 0.6%), the water bath (8.4% ± 1.7%) or a 37°C control (6.6% ± 1.1%). The apoptosis-inducing effect of mEHT at 42°C was similar to that achieved with a water bath at 46°C. mEHT also increased expression of caspase-3, 8 and 9. All three hyperthermia methods increased intracellular heat shock protein 70 (Hsp70) levels, but only mEHT greatly increased the release of Hsp70 from cells. Calreticulin and E-cadherin levels in the cell membrane also increased after mEHT treatment, but not after cCHT or water bath. These results suggest that mEHT selectively deposits energy on the cell membrane and may be a useful treatment modality that targets cancer cell membranes.

Ten new wheat γ-gliadin gene sequences are reported and an analysis of γ-gliadin gene family structure is carried out using all known γ-gliadin sequences. The new sequences comprise four genomic clones with significantly more flanking DNA than previously reported, and six cDNA clones from a wheat endosperm EST project. Analysis of extended flanking DNA from the genomic clones indicates the limits of conservation of γ-gliadin DNA sequence that are similar to those previously found with other gliadin and glutenin genes and that are theorized to define the DNA sequence necessary for gene control. Most of the flanking DNA is not homologous to any reported DNA sequence, and one flanking region contains the first MITE-like (miniature inverted transposable element) DNA sequence associated with gliadin genes. About a quarter of the encoded polypeptides would contain a free cysteine residue -an observation that may relate to reports that at least some gliadins can participate in wheat endosperm glutenin polymer formation. The new sequences represent both genes closely related to those previously reported and a new sub-class of γ-gliadins.

The DNA sequences of two full-length wheat ω-gliadin prolamin genes (ωF20b and ωG3) containing significant 5´ and 3´ flanking DNA sequences are reported. The ωF20b DNA sequence contains an open reading frame encoding a 30,460-Dalton protein, whereas the ωG3 sequence would encode a putative 39,210-Dalton protein except for a stop codon at amino-acid residue position 165. These two ω-gliadin genes are closely related and are of the ARQ-/ARE-variant type as categorized by the derived N-terminal amino-acid sequences and aminoacid compositions. The ω-gliadins were believed be related to the ω-secalins of rye and the C-hordeins of barley, and analyses of these complete ω-gliadin sequences confirm this close relationship. Although the ω-type sequences from all three species are closely related, in this analysis the rye and barley ω-type sequences are the most similar in a pairwise comparison. A comparison of ω-gliadin flanking sequences with respect to that of their orthologs and with respect to wheat gliadin genes suggests the conservation of flanking DNA necessary for gene function. Sequence data for members of all major wheat prolamin families are now available.

No abstract

Gold nanoparticles (AuNPs) are widely applied to the diagnosis and treatment of cancer and can be modified to contain target-specific ligands via gold-thiolate bonding. This study investigated the pharmacokinetics and microdistribution of antibody-mediated active targeting gold nanoparticles in mice with subcutaneous lung carcinoma. We conjugated AuNPs with cetuximab (C225), an antibody-targeting epidermal growth factor receptor (EGFR), and then labeled with In-111, which created EGFR-targeted AuNPs. In vitro studies showed that after a 2 h incubation, the uptake of C225-conjugated AuNPs in high EGFR-expression A549 cells was 14.9-fold higher than that of PEGylated AuNPs; furthermore, uptake was also higher at 3.8-fold when MCF7 cells with lower EGFR-expression were used. MicroSPECT/CT imaging and a biodistribution study conducted by using a A549 tumor xenograft mouse model provided evidence of elevated uptake of the C225-conjugated AuNPs into the tumor cells as a result of active targeting. Moreover, the microdistribution of PEGylated AuNPs revealed that a large portion of AuNPs remained in the tumor interstitium, whereas the C225-conjugated AuNPs displayed enhanced internalization via antibody-mediated endocytosis. Our findings suggest that the anti-EGFR antibody-conjugated AuNPs are likely to be a plausible nano-sized vehicle for drug delivery to EGFR-expressing tumors.