A biometric study of some hybridizing Crataegus populations in Denmark

Crataegus curvisepala Lindm., C. laevigata (Poiret) DC. and C. monogyna Jacq. (Rosaceae) form hybrid complexes in Denmark due to introgression. C. palmstruchii Lindm. seems to be variously introgressed individuals of C. laevigata. C. eremitagensis Raunk., C. raavadensis Raunk. and C. schumacheri Raunk. apparently belong to C. curvisepala x laevigata. The delimitation between C. curvisepala x laevigata and C. laevigata x monogyna is discussed.     

Upregulation of c-FLIP-short in response to TRAIL promotes survival of NSCLC cells,which could be suppressed by inhibition of Ca2+/calmodulin signaling

TNF-related apoptosis-inducing ligand (TRAIL) is a promising cytokine for killing tumor cells. However, a number of studies have demonstrated that different cancer cells resist TRAIL treatment and, moreover, TRAIL can promote invasion and metastasis in resistant cells. Here we report that TRAIL rapidly activates caspase-8 in a panel of non-small-cell lung carcinomas (NSCLCs). Adenocarcinomas derived from the lung in addition to high caspase-8 expression are characterized by increased expression of DR4 compared with adjacent non-neoplastic tissues. Blocking DR4 or lowering caspase-8 expression significantly reduced apoptosis in NSCLC cell lines, indicating the importance of DR4 and signifying that higher levels of caspase-8 in lung adenocarcinomas make them more susceptible to TRAIL treatment. Despite rapid and robust initial responsiveness to TRAIL, surviving cells quickly acquired resistance to the additional TRAIL treatment. The expression of cellular-FLIP-short (c-FLIP_S) was significantly increased in surviving cells. Such upregulation of c-FLIP_S was rapidly reduced and TRAIL sensitivity was restored by treatment with cycloheximide. Silencing of c-FLIP_S, but not c-FLIP-long (c-FLIP_L), resulted in a remarkable increase in apoptosis and significant reduction of clonogenic survival. Furthermore, chelation of intracellular Ca²⁺ or inhibition of calmodulin caused a rapid proteasomal degradation of c-FLIP_S, a significant increase of the two-step processing of procaspase-8, and reduced clonogenicity in response to TRAIL. Thus, our results revealed that the upregulation of DR4 and caspase-8 expression in NSCLC cells make them more susceptible to TRAIL. However, these cells could survive TRAIL treatment via upregulation of c-FLIP_S, and it is suggested that blocking c-FLIP_S expression by inhibition of Ca²⁺/calmodulin signaling significantly overcomes the acquired resistance of NSCLC cells to TRAIL.     

On the history of nuclear matrix manifestation

The nonchromatin proteinous residue of the cell nucleus was revealed in our laboratory as early as in 1948 and then identified by light and electron microscopy as residual nucleoli,intranuclear network and nuclear envelope before 1960,This structure termed afterwards as “nuclear residue“,“nuclear skeleton“,“nuclear cage“,“nuclear carcass“etc.,was much later(in 1974) isolated,studied and entitled as “nuclear matrix“ by Berezney and Coffey,to whom the discovery of this residual structure is often wronly ascribed.The real history of nuclear matrix manifestation is reported in this paper.     

Does urbanization affect selective pressures and life‐history strategies in the common blackbird (Turdus merula L.)?

Urbanization, one of the most extreme land‐use alterations, is currently spreading, and the number of species confronting these changes is increasing. However, contradictory results of previous studies impede a clear interpretation of which selective pressure (nest predation or food limitation) is more important in urban habitats compared with natural situations, and whether birds can confront them by adjusting their life‐history strategies. We investigated life‐history syndromes of three common blackbird (Turdus merula) populations differing in their human influence (urban, rural, and woodland). We analysed daily nest predation and nestling starvation rates to assess the relative importance of these selection pressures in each habitat. Simultaneously, several life‐history traits were investigated to determine if T. merula seem adapted to their main source of selection. Food limitation was more important in the city, whereas nest predation was the most important selective force in the forest. The rural habitat was characterized by an intermediate influence of these two factors. Life‐history syndromes, as the covariation of a suite of traits, confirmed these results because T. merula seem well adapted to the main cause of selection in each habitat. Our results are consistent with urbanization imposing new challenges on birds, and that they adaptively respond to them. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 759–766.     

Analysis of Polymorphic Variants of Gene <Emphasis Type="Italic">GIPC1</Emphasis> CGG Repeats in Healthy Individuals and in Patients with Breast Cancer and Non-Small Cell Lung Cancer

The GIPC1 gene product promotes clustering of some transmembrane receptors, including those involved in carcinogenesis, and protects them against ubiquitin-dependent degradation. The 5′ untranslated region of GIPC1 contains a polymorphic trinucleotide CGG repeat, which has not been characterized earlier. In the present study, we have carried out comparative analysis of the allele and genotype frequencies of this repeat in 129 samples of breast cancer (BC), 58 samples of non-small cell lung cancer (NSCLC), and 215 samples of healthy donors. The CGG repeat in the 5′ untranslated GIPC1 gene region was shown to be highly polymorphic and represented by at least eight alleles. Alleles CGG_10–13 were major, occurring at frequencies of 22, 41, 27, and 9%, respectively; the total frequency of the remaining alleles was approximately 1%. Heterozygosity of the CGG repeat was 0.70. Allele CGG ₁₂ was shown to be associated with high risk of developing NSCLC (α = 0.05).     

Downregulation of RBSP3/CTDSPL, NPRL2/G21, RASSF1A, ITGA9, HYAL1, and HYAL2 in non-small cell lung cancer

Chromosomal and genome abnormalities of 3p are frequent in many epithelial tumors, including lung cancer. Several critical regions with a high frequency of hemi-and homozygous deletions in tumors are known for 3p, and more than 20 cancer-related genes occur in 3p21.3. Quantitative real-time PCR was used to measure the mRNA level for tumor-suppressor and candidate genes of 3p21.3 (RBSP3/CTDSPL, NPRL2/G21, RASSF1A, ITGA9, HYAL1, and HYAL2) in major types of non-small cell lung cancer (NSCLC): squamous cell lung cancer (SCC) and lung adenocarcinoma (AC). A significant (2-to 100-fold) and frequent (44–100%) decrease in mRNA levels was observed in NSCLC. The mRNA level decrease and its frequency depended on the histological type of NSCLC for all genes. The downregulation of RASSF1A and ITGA9 was significantly associated with AC progression; the same tendency was observed for RBSP3/CTDSPL, NPRL2/G21, HYAL1, and HYAL2. In SCC, the downregulation of all genes was not associated with the clinical stage, tumor cells differentiation, and metastasis in lymph nodes. The RBSP3/CTDSPL, NPRL2/G21, ITGA9, HYAL1, and HYAL2 mRNA levels significantly (5-to 13-fold on average) decreased at a high frequency (83–100%) as early as SCC stage I. Simultaneous downregulation of all six genes was observed in some tumor samples and was independent of the gene position in 3p21.3 and the functions of the protein products. The Spearman correlation coefficient r _s was 0.63–0.91, p < 0.001. The highest r _s values were obtained for gene pairs ITGA9-HYAL2 and HYAL1-HYAL2, whose products mediate cell-cell adhesion and cell-matrix interactions; coregulation of the genes was assumed on this basis. Both genetic and epigenetic mechanisms proved to be important for downregulation of RBSP3/CTDSPL and ITGA9. This finding supported the hypothesis that the cluster of cancerrelated genes in the extended 3p21.3 locus is simultaneously inactivated during the development and progression of lung cancer and other epithelial tumors. A significant and frequent decrease in the mRNA level of the six genes in SCC could be important for developing specific biomarker sets for early SCC diagnosis and new approaches to gene therapy of NSCLC.     

The Development of Chronic Obstructive Pulmonary Diseases Correlates with Microsatellite DNA Instability

Allele distribution at a highly polymorphic minisatellite adjacent to the c-Hras1 gene as well as deletions of microsatellite markers, D3S966, D3S1298, D9S171, and a microsatellite within p53 gene, were examined in bronchial epithelium specimens obtained from 53 chronic obstructive pulmonary disease (COPD) patients and healthy donors. A higher frequency of rare Hras1minisatellite alleles in COPD patients than in the individuals without pulmonary pathology (6.6% versus 2.2%; P < 0.05) was shown. This difference was most pronounced in the group of ten COPD patients with idiopathic pulmonary fibrosis. Three of these patients had rare Hras1 minisatellite allele (P < 0.02 in comparison with healthy controls). Alterations in at least one of the microsatellite markers (deletions or microsatellite instability) were detected in bronchial epithelium samples obtained from: 4 of 10 COPD patients with pneumofibrosis (40%); 15 of 43 COPD patients (34.9%) without pneumofibrosis; and 8 of 20 tobacco smokers (40%) without pulmonary pathology. These defects were not observed in the analogous samples obtained from healthy nonsmoking individuals. No statistically significant differences were revealed between COPD patients and healthy smokers upon comparison of both the total number of molecular defects and the number of defects in the individual chromosomal loci. The total number of molecular defects revealed in bronchial epithelium samples from the individuals of two groups examined correlated with the intensity of exposure to tobacco smoke carcinogens (r = 0.28; P < 0.05). These findings suggest that rare alleles at theHras1 locus may be associated with hereditary predisposition to COPD and the development of pneumofibrosis, while mutations in microsatellite markers result from exposure to tobacco smoke carcinogens and are not associated with the appearance of these pathologies.     

Methylation Profile of Several Tumor Suppressor Genes in Non-Small-Cell Lung Cancer

Multiplex methylation-sensitive PCR was employed in studying the methylation of CpG islands in the RB1, p16/CDKN2A, p15/CDKN2B, p14/ARF, CDH1, HIC1, and N33 5 regions in non-small cell lung cancer (51 tumors). Methylation was observed for the two suppressor genes involved in controlling the cell cycle through the Cdk–Rb–E2F signaling pathway, RB1 (10/51, 19%) and p16 (20/51, 39%). The highest methylation frequencies were established for CDH1 (72%) and HIC1 (82%). The CpG islands of p14 and p15 proved to be nonmethylated. At least one gene was methylated in 90% (46/51) tumors and no gene, in 10% (5/51) tumors. In addition, the genes were tested for methylation in peripheral blood lymphocytes of healthy subjects. Methylation frequency significantly differed between tumors and normal cells in the case of RB1, p16, CDH1, HIC1, and N33. Gene methylation frequency was tested for association with histological type of the tumor and stage of tumor progression. Methylation index of a panel of tumor suppressor genes was established for groups of tumors varying in clinical and morphological parameters.     

Comparison of Aberrant Methylation of CpG Islands in the p16/CDKN2A and p14/ARF Promoters in Non-Small Cell Lung Cancer and Acute Lymphoblastic Leukemia

Multiplex methylation-sensitive (MSe-PCR) and methylation-specific (MSp-PCR) PCRs were used to detect aberrant methylation of CpG islands in the promoter regions and first exons of p16/CDKN2A and p14/ARF in non-small cell lung cancer (NSCLC, 54 specimens) and B-cell acute lymphoblastic leukemia (B-ALL, 61 specimens). A difference in CpG methylation was observed for individual specimens and for the two malignancies. A high methylation frequency of the first exon of p16/CDKN2A was detected both in NSCLC (68%) and in B-ALL (55%). The CpG island of the p14/ARF first exon proved to be nonmethylated in both malignancies. Particular CpG-rich fragments were examined in the p16/CDKN2A and p14/ARF promoters. It was shown that methylation frequency can differ between the 5 regions of one promoter. The sensitivity was compared for MSe-PCR and MSp-PCR, which are commonly employed in methylation analysis.