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Inducible heat shock protein (HspA1A) promotes tumor cell growth and survival. It also interacts with effector cells of the innate immune system and affects their activity. Recently, we showed that the direct contact of ovarian cancer cells, isolated from tumor specimens, with neutrophils intensified their biological functions. Our current experiments demonstrate that the activation of neutrophils, followed by an increased production of reactive oxygen species, by cancer cells involves the interaction of HspA1A from cancer cells with Toll-like receptors 2 and 4 expressed on the neutrophils’ surface. Our data may have a practical implication for targeted anticancer therapies based, among other factors, on the inhibition of HspA1A expression in the cancer cells.  相似文献   
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Oral cavity cancer belongs to head-and-neck squamous cell carcinoma group. The purpose of the study was to assess the levels of certain proteins in a tumour and surgical margin in a group of patients with oral cavity cancer. The levels of DAPK1, MGMT, CDH1, SFRP1, SFRP2, RORA, TIMP3, p16, APC and RASSF1 proteins were measured by ELISA in tissue homogenates. The protein levels of DAPK1, MGMT, CDH1, SFRP2 and RASSF1 were significantly higher in tumour tissue than in the margin, contrary to TIMP3 which was lower in the tumour itself. DAPK1 level in the tumour was significantly higher in females than in males, the MGMT and p16 levels were lower in the tumours with lymph node metastasis (N1 + N2) than in N0 samples. The CDH1 expression was higher in a group with smoking habits, whereas TIMP3 was lower in this group. Changes in the levels of proteins in tumour and surgical margin may be either reflective of tumour occurrence and development, or they might be also responsible for the progress and reoccurrence of the disease. Levels of the studied proteins might be good prognostic factors; however, further studies are required.  相似文献   
334.
Three triticale cDNAs encoding inhibitors of cysteine endopeptidases, belonging to phytocystatins, have been identified and designated as TrcC-1, TrcC-4 and TrcC-5. Full-length cDNAs of TrcC-1 (617?bp) and TrcC-4 (940?bp), as well as a fragment of TrcC-5 cDNA (369?bp), were obtained. A high-level identity of the deduced amino acid sequence of TrcCs with other known phytocystatins, especially with wheat and barley, has been observed. Moreover, the presence of conserved domain, containing the G and W residues, the sequence of QxVxG and the sequence of LARFAV, characteristic for plant cysteine endopeptidase inhibitors, has been noted. The profiles of TrcC-1 and TrcC-5 mRNA levels in the developing seeds of two triticale cultivars that differ in their resistance to preharvest sprouting (Zorro and Disco) were similar. However, the expression of TrcC-4 was, higher in the developing seeds, and in the scutellum of germinating seeds of a cultivar more resistant to preharvest sprouting (Zorro) than in the less resistant (Disco). Additionally, the expression of TrcC-4 remained longer in developing seeds of Zorro as compared to Disco. The performed studies suggest that TrcC-4 might have an influence on the higher resistance of Zorro cultivar to preharvest sprouting.  相似文献   
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Leaf undulation is used as a diagnostic feature in the taxonomy of different taxa of the Epipactis (Orchidaceae) genus. It is considered a specifically important trait, apart from the column (gynostemium) structure, in the identification of E. muelleri. However, leaf undulation is a common developmental phenomenon in various plants, including orchids, thus the main goal of the research presented was to validate the usefulness of this feature in Epipactis taxonomy. In the course of this study, the leaf structure of six Epipactis species was analyzed, i.e., E. albensis, E. atrorubens, E. helleborine, E. muelleri, E. palustris and E. purpurata. The leaf margin outline and the cellular pattern of the leaf surface, as well as the presence of papillae, were examined in detail. The results obtained showed that in all taxa analyzed, representing different groups of the Epipactis genus, leaf undulation was present. The phenomenon was related to leaf blade development and the local differential growth of leaf sectors rather than to the taxonomic position of the species. Therefore, leaf undulation studied in Helleborines does not have a diagnostic value as a non-programmed intrinsic feature and should not be applied to taxa identification. The valid trait in Epipactis classification (including E. muelleri) is the column structure.  相似文献   
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Orbital fibroblast differentiation to adipocytes is a peroxisome proliferator-activated receptor g (PPARg)-dependent process essential for pathogenic tissue remodeling in Graves' orbitopathy (GO). PPARg2 Pro12Ala polymorphism modulates expression and/or function of the molecule encoded by this gene and is a promising locus of GO. Here, we analyzed associations of PPARg2 Pro12Ala with clinical manifestation of GO in 742 Polish Caucasians including 276 Graves' disease (GD) patients. In our study, the Ala12 allele and Ala12 variant (Ala12Ala and/or Pro12Ala genotype) decreased the risk of GO (p?=?0.000012 and p?=?0.00013). Moreover, Ala12Ala genotype was observed only in patients without GO (p?=?0.002). GD patients with Ala12 variant had less active and less severe eye symptoms. Female carriers of the Ala12 allele rarely developed GO, but the marker was not related to symptoms of GO. The opposite finding was recorded in males, in whom the studied polymorphism was related to activity, but not to the development, of GO. In Ala12 variant carriers without familial history of thyroid disease, risk of GO was lower than in persons with a familial background. The Ala12 allele seemed to protect smokers from GO, but in nonsmokers, such a relation was not obvious. A multivariate analysis indicated the Pro12Ala marker as an independent risk factor of eye symptoms (p?=?0.0001) and lack of Ala increases the risk of GO 3.24-fold. In conclusion, the gain-of-function Ala12 variant protects against GO and modulates the course of the disease.  相似文献   
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