Studies on the role of osteopontin-1 in endometrial cancer cell lines.

BACKGROUND: Osteopontin-1 is a well characterized protein in many tumour entities. Multiple roles in the processes invasion, metastasis and angiogenesis of tumours are attributed to osteopontin-1. The putative role of osteopontin-1 has not been characterized for endometrial cancer. MATERIAL AND METHODS: We investigated multiple endometrial cancer cell lines for osteopontin-1 mRNA- and protein-expression. Osteopontin-1 dependent effects were analysed in vitro by siRNA inhibition. RESULTS: All endometrial cell lines expressed osteopontin-1. Expression of osteopontin-1 was successfully inhibited by specific siRNA. Cells with reduced osteopontin-1 expression showed decreased migration in the Boyden chamber assay and invasion was reduced in the wound-healing assay. Osteopontin-1 seems to play a role in apoptotic processes of endometrial cancer cells. Inhibition of osteopontin-1 expression was associated with an increased susceptibility for radiation therapy. CONCLUSION: Osteopontin-1 seems to play a role in endometrial cancer. Inhibition of osteopontin-1 expression leads to a higher susceptibility for radiation therapy. Our results suggest that a reduced expression of osteopontin-1 in endometrial cancer could inhibit the development of invasion and metastasis in these cells.

Absence of donor-specific anti-HLA antibodies after ABO-incompatible heart transplantation in infancy: altered immunity or age?

Specific B-cell tolerance toward donor blood group antigens develops in infants after ABO-incompatible heart transplantation, whereas their immune response toward protein antigens such as HLA has not been investigated. We assessed de novo HLA-antibodies in 122 patients after pediatric thoracic transplantation (28 ABO-incompatible) and 36 controls. Median age at transplantation was 1.7 years (1 day to 17.8 year) and samples were collected at median 3.48 years after transplantation. Antibodies were detected against HLA-class I in 21 patients (17.2%), class II in 18 (14.8%) and against both classes in 10 (8.2%). Using single-antigen beads, donor-specific antibodies (DSAs) were identified in six patients (all class II, one additional class I). Patients with DSAs were significantly older at time of transplantation. In patients who had undergone pretransplant cardiac surgeries, class II antibodies were more frequent, although use of homografts or mechanical heart support had no influence. DSAs were absent in ABO-incompatible recipients and class II antibodies were significantly less frequent than in children with ABO-compatible transplants. This difference was present also when comparing only children transplanted below 2 years of age. Therefore, tolerance toward the donor blood group appears to be associated with an altered response to HLA beyond age-related effects.

Latent class analysis of violence against adolescents and psychosocial outcomes in refugee settings in Uganda and Rwanda.

BACKGROUND: Little is known about violence against children in refugee camps and settlements, and the evidence-base concerning mental health outcomes of youth in refugee settings in low and middle-income countries is similarly small. Evidence is needed to understand patterns of violence against children in refugee camps, and associations with adverse mental health outcomes. METHODS: Surveys were conducted with adolescent refugees (aged 13-17) in two refugee contexts - Kiziba Camp, Rwanda (n = 129) (refugees from Democratic Republic of Congo) and Adjumani and Kiryandongo refugee settlements, Uganda (n = 471) (refugees from South Sudan). Latent Class Analysis was utilized to identify classes of violence exposure (including exposure to witnessing household violence, verbal abuse, physical violence and sexual violence). Logistic regressions explored the association between latent class of violence exposure and symptoms of depression and anxiety. RESULTS: In Rwanda, a two-class solution was identified, with Class 1 (n = 33) representing high levels of exposure to violence and Class 2 (n = 96) representing low levels of exposure. In Uganda, a three-class solution was identified: Class 1 (high violence; n = 53), Class 2 (low violence, n = 100) and Class 3 (no violence, n = 317). Logistic regression analyses indicated that latent violence class was associated with increased odds of high anxiety symptoms in Rwanda (AOR 3.56, 95% CI 1.16-0.95), and high v. no violence class was associated with depression (AOR 3.97, 95% CI 1.07-7.61) and anxiety symptoms (AOR 2.04, 95% CI 1.05-3.96) in Uganda. CONCLUSIONS: The present results support the existing evidence-base concerning the association between violence and adverse mental health outcomes, while identifying differences in patterns and associations between refugee youth in two different contexts.

Complete sequence, expression and evolution of two members of the hexamerin protein family during the larval development of the rice moth, Corcyra cephalonica.

Three distinct types of storage hexamerins are expressed in the "last-instar" larvae of the rice moth, Corcyra cephalonica. A cDNA expression library was constructed from fat body-RNA and screened with a polyclonal antibody raised against purified hexamerin (SP2) of Corcyra cephalonica. Two slightly different "full-length" hexamerin cDNA clones (Hex2a and Hex2b) were isolated and sequenced. Both include open reading frames of 2109 bp which are translated into polypeptides of 703 amino acids with 92.5% identity. Signal peptides of 19 amino acids are present at the N-termini. The 684 amino acids native proteins have a high content of aryl groups (17.6%). According to both the criteria for amino acid composition and the phylogenetic analysis, Hex2a and Hex2b belong to the lepidopteran arylphorins. Northern blot studies revealed that the Hex2 genes are species- and tissue-specifically expressed in fat body cells of "last-instar" (= 5th) larvae.

Downregulation of AKT reverses platinum resistance of human ovarian cancers in vitro.

Platinum resistance is the most crucial problem for treatment of ovarian cancer. Increasing evidence points towards AKT overexpression as a mechanistic reason for this clinical condition. The present study evaluates the effect of overexpression and downregulation of AKT on the sensitivity to cisplatin in a platinum-resistant human ovarian cancer cell line and the corresponding platinum-sensitive parental cell line. A2780 and A2780cis ovarian cancer cell lines were stably transfected with an AKT-sense and AKT-antisense plasmid. Successful transfection was evaluated by western blot analysis. Cytotoxic effects of cisplatin were evaluated by metabolic (MTT) and clonogenicity assays as well as by FACS analysis. AKT overexpression (confirmed by western blotting) converted platinum-sensitive A2780 into platinum-resistant cells as shown by MTT assay. Importantly, platinum resistance of A2780cis cells could be reversed by downregulation of AKT, as demonstrated by MTT and clonogenicity assays and FACS analysis. Our data provide strong evidence that cisplatin resistance in ovarian cancer is mediated by AKT overexpression and can be overcome by AKT downregulation, thus, providing a rationale for clinical phase II/III studies combining AKT inhibitors with cisplatin.

Cancer immunotherapy based on recombinant Salmonella enterica serovar Typhimurium aroA strains secreting prostate-specific antigen and cholera toxin subunit B.

Prostate cancer is the most common malignant tumor in men and is normally associated with increased serum levels of prostate-specific antigen (PSA). Therefore, PSA is one potential target for a prostate cancer vaccine. In this study we analyzed the functionality of new bacterial PSA vaccines, expressed and secreted via the hemolysin (HlyA) secretion system of Escherichia coli, the prototype of Type I secretion systems (T1SS) using an attenuated Salmonella enterica serovar Typhimurium aroA strain as carrier. The data demonstrate that a bacterial live vaccine encompassing T1SS in combination with cholera toxin subunit B can be successfully used for delivery of PSA to induce cytotoxic CD8+ T-cell responses resulting in an efficient prevention of tumor growth in mice.

Functional dissection of the hexamerin receptor and its ligand arylphorin in the blowfly Calliphora vicina.

The process of receptor-mediated uptake of hexamerin storage proteins from insect haemolymph by fat body cells is a unique feature of the class Insecta. We identified the binding domains of the hexamerin receptor and the hexamerin ligand arylphorin in the blowfly, by means of the yeast-two-hybrid-system. The receptor-binding domain of arylphorin was located within domain 3 of the arylphorin monomer. The ligand-binding domain of the hexamerin receptor was mapped to the extreme N-terminus of the receptor. The binding domains identified exhibit no similarity to any functional protein domains known to date. Additionally, we identified two previously unknown protein-interactors of the hexamerin receptor. The results of this study provide further insights regarding the mechanism of the receptor-mediated endocytosis of storage proteins in insects.

Corazonin gene expression in the waxmoth Galleria mellonella.

We cloned and sequenced a full length cDNA coding for [Arg7]-corazonin in the greater wax moth Galleria mellonella. The deduced corazonin preprohormone consists of a nineteen amino acid signal peptide, the actual eleven amino acid corazonin sequence, followed by a Gly serving for amidation, a Lys-Arg processing site and an eighty amino acid corazonin precursor-related peptide. The data confirm the phylogenetic conservation of the actual corazonin sequence. The signal peptide and the precursor-related peptide exhibit a similar spacing of a few amino acids as detected in the corazonin preprohormone of Drosophila melanogaster. Northern blots and in situ hybridization experiments revealed that the G. mellonella corazonin gene is tissue-specifically expressed in four pairs of lateral neurosecretory cells in the brains of penultimate and last instar larvae, as well as of pupae and adults. No corazonin mRNA was detected in other cells of the nervous system, fat body, gut, and several other organs.