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Abstract: Objective. : To investigate the consequences of IGF proteins dysfunction in development of endometrial adenocarcinomas. Methods. : The expression of IGF 2 and IGF 1R was correlated with the expression of IGF 2R and apoptosis rate in 59 human endometrial adenocarcinomas, 10 endometrial hyperplasias and 7 normal tissues. The presence of mutations in the IGF 2R gene was followed in 46 adenocarcinomas. We also examined the effect of IGF 1 receptor blockage on cancer cell proliferation. In groups of either IGF 2-positive or IGF 2-negative tumors (stages III and IV) the expression of IGF 1 and IGF 1R was correlated with cell proliferation index and telomerase activity. Results. : The expression of IGF 2 and IGF 1R was much higher in malignant tissue of stages III and IV than in tumors of stages I and II and normal or hyperplastic endometrium. This correlated with a decreased apoptosis rate and IGF 2R expression. Eight adenocarcinomas expressed biallelic mutation of the IGF 2R gene. The specific inhibition of IGF 1R and IGF 2 decreased tumor cell proliferation in IGF 2/IGF 1R-positive tumors. Furthermore, the positive correlation between increased expression of IGF 1 and IGF 1R proteins and increased telomerase activity and cell proliferation index was found in both IGF 2-negative and IGF 2-positive tumors. Conclusion. : Our data suggest that IGF 1, IGF 2 and their receptors are involved in the progression of endometrial adenocarcinomas. As cancer cell proliferation can be abrogated by blocking mRNA or protein products of these genes, tumors with extensive involvement of the IGF 2 pathway would be candidates for the therapeutics strategies aimed at interference with this pathway. [Copyright &y& Elsevier]

Purpose. Although there are many controversial reports about the effect of p53 and p21WAF1/CIP1 overexpression in different human tumor cells, the p53 gene is shown to be a more effective candidate for cancer gene therapy because of its more pronounced ability to induce apoptosis. In the present study, we present the effect of p53 and p21WAF1/CIP1 overexpression on mouse renal carcinoma cells in vitro and in vivo. Methods. p53 and p21WAF1/CIP1 genes were introduced into Renca cells using adenoviral vectors (Ad5CMV-p53 and Ad5CMV-p21). The induction of apoptosis was measured using Annexin V assay and DNA fragmentation analysis. The expression of proteins was examined using immunocytochemistry and Western blot methods. The ability of adenoviral vectors to inhibit tumorigenicity of Renca cells, as well as the growth of pre-established tumors was measured. Results. In vitro growth assays revealed higher growth suppression after Ad5CMV-p21 infection. Although both vectors induced apoptosis, Ad5CMV-p53 was slightly more efficient. In vivo studies in Balb/c mice, demonstrated that tumorigenicity was completely suppressed by Ad5CMV-p21. Besides this, Ad5CMV-p21 significantly inhibited the growth of established tumors, while Ad5CMV-p53 did not. Conclusions. These data suggest that p21WAF1/CIP1 is a more potent growth suppressor than p53 of mouse tumor cells Renca. The divergent responses of tumor cells to p21WAF1/CIP1 overexpression could be due to various networks that differ between species. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about Helicobacter pylori in oral aphthous ulcers.

Background: Toll-like receptor 3 (TLR3) activation in tumor cells induces apoptosis. We investigated the effect of TLR3 ligand (poly(I:C)) in combination with chemotherapeutics applied to human pharyngeal carcinoma cells as a possible antitumor therapy. Methods:Human pharyngeal cancer cell lines were studied (FaDu and Detroit 562). Cytotoxicity assays and apoptosis assays (annexin V staining and caspase 3/7 activity measurements) were used to investigate the cytotoxic effects. By using TLR3 siRNA we confirmed that the observed effect is TLR3-dependent. Results: We found that the combined application of poly(I:C) and chemotherapeutics (cisPt, HU, 5-FU and MTX) has a stronger inhibitory effect on cell growth in tumor cells expressing functional TLR3 as compared with a single treatment. This is a result of TLR3-dependent apoptosis. Conclusion: Our study showed that a combined application of the two agents already being used in tumor therapy could lower the necessary dosage of chemotherapeutics, leading to fewer side effects. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Genetic syndromes caused by chromosomal aberrations involve a recognizable pattern of multiple congenital anomalies with increased neonatal and infant mortality, making care challenging for the family, primary care practitioners, and specialists. About 28% of children born with trisomy 13 die during the fi rst week of life. The median life expectancy is about 2.5 days. We present a 12-year-old girl, the longest living patient with Patau syndrome in Croatia, followed-up from the birth until the age of 12 years. The conventional nonintervention approach has been revised and we suggest changing the traditional view of the condition. [ABSTRACT FROM AUTHOR]

Toll-like receptors (TLR) are employed by the innate immune system to detect microbial pathogens based on conserved microbial pathogen molecules. For example, TLR9 is a receptor for CpG-containing microbial DNA, and its activation results in the production of cytokines and type I interferons from human B cells and plasmacytoid dendritic cells, respectively. Both are required for mounting an efficient antibacterial or antiviral immune response. These effects are mimicked by synthetic CpG oligodeoxynucleotides (ODN). Although several hyporesponsive TLR9 variants have been reported, their functional relevance in human primary cells has not been addressed. Here we report a novel TLR9 allele, R892W, which is hyporesponsive to CpG ODN and acts as a dominant-negative in a cellular model system. The R892W variant is characterized by increased MyD88 binding and defective co-localization with CpG ODN. Whereas primary plasmacytoid dendritic cells isolated from a heterozygous R892W carrier responded normally to CpG by interferon-α production, carrier B cells showed impaired IL-6 and IL-10 production. This suggests that heterozygous carriage of a hyporesponsive TLR9 allele is not associated with complete loss of TLR9 function but that TLR9 signals elicited in different cell types are regulated differently in human primary cells. [ABSTRACT FROM AUTHOR]

nm23 was identified as a metastasis suppressor gene but is also appointed to a number of other biological functions. The goal of this study was to reveal the influence of ectopic expression of nm23-H1 and nm23-H2 on proliferation properties of head and neck tumor cells. The proliferation rate of transfected cells was evaluated using EGFP reporter system and flow cytometry. HEp-2 and CAL 33 cells transiently transfected with nm23 cDNA containing constructs exhibited enhanced proliferation. CAL 27 cells constitutively expressing GFP-Nm23-H2 protein, exhibited intense proliferation the first day after seeding, while the GFP-Nm23-H1 expressing clone started to proliferate after one-day lag period. The results on transiently transfected HEp-2 and CAL 33 cells generally confirmed previous findings connecting nm23 expression with altered proliferation of head and neck tumors. We speculate that the effects observed on stably transfected CAL 27 clones are due to their different attachment properties. [ABSTRACT FROM AUTHOR]

Rett syndrome (RTT) is an X-linked dominant neurodevelopmental disorder almost exclusively affecting females and is usually sporadic. Mutations in MECP2 gene have been found in more than 80% of females with typical features of RTT. In this study, we analyzed 15 sporadic cases of RTT. In 7 of 15 patients (47%), we detected pathogenic mutations in the coding parts of MECP2 fourth exon. We found two missense (T158M, R133C), two nonsense (R168X, R270X), two frameshift mutations (P217fs and a double deletion of 28-bp at 1132–1159 and 10-bp at 1167–1176), and one in-frame deletion (L383_E392del10). To our knowledge, the last two mutations have not been reported yet. We also detected one previously described polymorphism (S194S). In conclusion, these results show that the fourth exon should be the first one analyzed because it harbors most of the known mutations. Moreover, mutation-negative cases should be further analyzed for gross rearrangements. This is the first study of its kind in Croatia and it enabled us to give the patients an early confirmation of RTT diagnosis. [ABSTRACT FROM AUTHOR]

The human Nm23-H1/NDPK A and Nm23-H2/NDPK B encode for two subunits of nucleoside diphosphate kinase—a ubiquitous enzyme that transfers the terminal phosphates from ATP to (d)NDPs. Although having an 88% amino acid sequence identity and an already assigned biochemical role in the cell, the two subunits appear to have additional and distinctive cell functions. In particular, both subunits have been reported to be involved in tumor progression and metastasis. The aim of this study was to determine the specific, and potentially distinct, localizations of both subunits in tumor cells of different origin and differentiation and therefore to search for a possible link between their localization and the stage of disease. We used the GFP reporter system to analyze the ectopic expression of GFP-Nm23 proteins in head and neck tumor cell lines by fluorescent microscopy techniques. Our experiments revealed that GFP-fused Nm23-H1 and -H2 proteins display the same localization in transfected cells, regardless of their origin and differentiation status. The proteins are principally found in the cytosol and the endoplasmic reticulum. Moreover, some cells exhibit nuclear staining, which appears to be cell cycle-dependent. [Copyright &y& Elsevier]

Nested PCR was used for the detection of Helicobacter pylori DNA in specimens collected from seven different topographic sites in the oral cavity. Out of 161 patients, only 21 (13.04%) were positive. There was no correlation between H. pylori status and patient diagnosis and age. No preferential site for bacterial colonization was found in the oral cavity, nor was an association established between a bacterial presence and ulcerated versus non-ulcerated lesions. The results indicate that the oral mucosa does not appear to represent a preferred site of colonization for H. pylori. Furthermore, the evidence presented in this paper suggests that H. pylori is not pathogenic in the oral cavity, nor is it associated with common oral pathologic processes. [ABSTRACT FROM AUTHOR]