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This review deals with effects of environmental and physicochemical factors affecting polyaromatic hydrocarbon (PAH) elimination from smoked meat products and liquid smoke flavoring (LSF). In the introductory part, some essential information are aimed at principles of food smoking and PAH formation during smoke generation as a result of incomplete wood combustion. Also, an application of alternative technology for food aromatization using LSF is briefly mentioned. Similarly, latest European legislation, biological effects, and analytical aspects of PAHs are mentioned concisely. The main part is devoted to physicochemical factors affecting the PAH content in smoked meat products, such as light, additional cooking, and packaging, which are able to decrease considerably PAH content in some meat products. The most important effect on PAH concentration decrease in LSF has low-density polyethylene (LDPE) package due to sorption processes on a surface of the plastic with subsequent diffusion into the plastic bulk. A less effective material is polyethylene terephthalate (PET), when only a surface adsorption process comes into account. Moreover, this process is affected also by other compounds presented in liquid media able to compete for the adsorption center on the PET surface.

Protein tyrosine kinases (PTKs) play a critical role in the manifestation of cancer cell properties, and respective signaling mechanisms have been studied extensively on immortalized tumor cells. To characterize and analyze commonly used cancer cell lines with regard to variations in the primary structure of all expressed PTKs, we conducted a cDNA-based sequence analysis of the entire tyrosine kinase transcriptome of 254 established tumor cell lines. The profiles of cell line intrinsic PTK transcript alterations and the evaluation of 155 identified polymorphisms and 234 somatic mutations are made available in a database designated ''Tykiva'' (tyrosine ki nome variant). Tissue distribution analysis and/or the localization within defined protein domains indicate functional relevance of several genetic alterations. The cysteine replacement of the highly conserved Y367 residue in fibroblast growth factor receptor 4 or the Q26X nonsense mutation in the tumor-suppressor kinase CSK are examples, and may contribute to cell line-specific signaling characteristics and tumor progression. Moreover, known variants, such as epidermal growth factor receptor G719S, that were shown to mediate anticancer drug sensitivity could be detected in other than the previously reported tumor types. Our data therefore provide extensive system information for the design and interpretation of cell line-based cancer research, and may stimulate further investigations into broader clinical applications of current cancer therapeutics.

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Using the polymerase chain reaction (PCR), a human kidney glutathione S-transferase (GST) alpha cDNA clone (GST alpha 12 K) was synthesized; it is identical to a known liver GST alpha cDNA clone except for one base change (G----A), indicating that an alpha class gene expressed in human kidney is similar to one expressed in human liver. Comparisons were made in the expression of GST alpha and GST pi between renal cell carcinoma and adjacent non-neoplastic tissue. Messenger RNA expression in 30 cases was determined by Northern blotting, and GST protein from nine of these cases was analyzed by HPLC. The GST alpha gene products were expressed at near-zero levels. The GST pi gene product was the predominant GST in tumors, but was decreased in absolute amount compared with control tissue, the tumor/control ratios for the GST pi gene obtained by Northern blots and HPLC analysis being 0.50 +/- 0.07 and 0.36 +/- 0.07 respectively. The resulting pattern in renal cell carcinoma therefore shows a predominance of GST pi. Since it is assumed that renal cell carcinoma derives from the proximal tubular epithelial cells which are high in GST alpha, this implies a dedifferentation in the GST expression pattern.