Recombinant human stem cell factor stimulates growth of a human glioblastoma cell line expressing c-kit protooncogene.

The growth of a panel of eight different human glioblastoma cell lines was examined in a human tumor cloning assay in agar, a tritiated thymidine uptake assay, and by counting cell numbers, in cultures performed in the absence or presence of increasing concentrations (1 to 100 ng/ml) of recombinant human stem cell factor (SCF). Growth of 7 of 8 cell lines was not significantly and reproducibly affected by recombinant human SCF. However, growth of the CRL 1620 cell line could be stimulated up to 5-fold by the cytokine. In contrast to the other cell lines investigated, CRL 1620 expressed the c-kit protooncogene assessed on the mRNA and protein level. Furthermore, SCF-induced proliferation of CRL 1620 cells was sensitive to the tyrosine kinase inhibitor erbstatin. Our data suggest that SCF can be operative in growth modulation of malignant cells outside the hematopoietic system, and this finding should be further studied for its possible clinical implications.     

Prostate and bone fibroblasts induce human prostate cancer growth in vivo: implications for bidirectional tumor-stromal cell interaction in prostate carcinoma growth and metastasis.

Prostate cancer selectively metastasizes to the axial skeleton to produce osteoblastic lesions, which suggests that bidirectional paracrine interactions exist between prostate cancer and bone cells. To evaluate the role of tumor-stromal cell interaction and stromal-specific growth factors in prostate cancer growth and dissemination, we coinoculated nontumorigenic human prostate cancer cells (LNCaP) and various tissue-specific fibroblasts subcutaneously in athymic mice. LNCaP tumors were induced most consistently by human bone fibroblasts (62%), followed by two prostate fibroblast cell lines (31% and 17%), but not by lung, kidney, or embryonic 3T3 fibroblasts. Carcinomas formed preferentially in male hosts, demonstrating in vivo androgen sensitivity. Immunohistochemical and biochemical techniques confirmed the human prostate component of these tumors and were paralleled by elevations in serum prostate specific antigen. In vitro mitogenic assays revealed a two-to three-fold bidirectional stimulation between LNCaP and bone or prostate fibroblast conditioned media, but not lung, kidney, or 3T3 fibroblast conditioned media. A novel method developed to deliver concentrated bone or prostate fibroblast conditioned media in vivo using a slowly absorbed matrix (gelfoam) also induced tumor formation, emphasizing the importance of fibroblast growth factors in LNCaP tumor formation. Northern analysis identified the stromal compartment as the primary source of extracellular matrix (collagen, fibronectin), while only LNCaP cells expressed transforming growth factor alpha. Although LNCaP and stromal cells express basic fibroblast growth factor (bFGF), the bidirectional paracrine-mediated mitogenic activity between these cells is not inhibited by anti-bFGF antibodies, suggesting that other undefined growth factors may be involved in stimulating LNCaP growth. These observations illustrate the importance of stromal-epithelial interaction in prostate tumor growth and suggest that extracellular matrix and paracrine-mediated growth factors play a role in prostate cancer growth and metastasis.     

Detection of the Arg702Trp, Gly908Arg and Leu1007fsinsC polymorphisms of the NOD2/CARD15 gene by real-time PCR with melting curve analysis.

Crohn's disease is a complex disorder, with multiple genetic traits. A frameshift mutation (Leu1007fsinsC) and two missense mutations (Gly908Arg and Arg702Trp) in the NOD2/CARD15 gene are strongly associated with susceptibility to Crohn's disease. The presence of one of these risk alleles confers a 2- to 4-fold increase in the risk of developing Crohn's disease, and the presence of two mutant alleles increases the risk over 20-fold. To facilitate the analysis of these polymorphisms, we developed three LightCycler assays to detect the missense mutations Arg702Trp and Gly908Arg and the frameshift mutation Leu100fsinsC in the NOD2/ CARD15 gene. All three assays can be run simultaneously on one LightCycler using identical cycling parameters. Analysis of 53 DNAs from Crohn's patients helped to identify carriers at allele frequencies similar to other Caucasian populations. The sequencing of such DNAs confirmed the accuracy of the assays. In conclusion, we present three rapid and robust assays to detect the Arg702Trp, the Gly908Arg and the Leu1007fsinsC ins mutations in the NOD2/CARD15 gene [corrected]     

The Relative Contribution of Domains of Quality of Life to Overall Quality of Life for Different Chronic Diseases

This study examined the contribution of the quality of life (QoL) domains physical, social and psychological functioning to the explanation of overall QoL. Various disorders may differentially affect QoL domains due to disease-specific factors and, consequently, the relationship between QoL domains and overall QoL may vary between diseases. We therefore studied this relationship for several diseases as well as the differential impact of these diseases on QoL. The present study had a cross-sectional design. We selected patients (aged 57 years and older) with one of the following eight chronic medical conditions: lung disorder, heart condition, hypertension, diabetes mellitus, back problems, rheumatoid arthritis, migraine, or dermatological disorders. The total group of respondents included 1457 patients and 1851 healthy subjects. Regression analyses showed that the domain of psychological functioning contributed to overall QoL for all disorders, whereas physical and social functioning contributed to overall QoL for some disorders. Differences were found between most patient groups and healthy subjects with respect to physical functioning; with respect to social and psychological functioning some groups differed from the healthy group. Explanations for the findings and implications for clinical practice are discussed.     

Factors affecting breastfeeding among women of Mexican origin or descent in Los Angeles.

Data on breastfeeding intentions and behavior were collected in prenatal and postpartum interviews as part of a study on first birth among 518 women of Mexican origin or descent in two Los Angeles hospitals. The prenatal intentions of 82 per cent of the women to breastfeed were maintained postpartum in one hospital but dropped sharply in the other. A greater number of hours a day with the baby in the hospital and earlier initiation of breastfeeding were associated with the hospital where prenatal breastfeeding intentions were more likely to be carried out. The intention to work postpartum was associated both with the decision not to breastfeed at all and with shorter intended duration of breastfeeding.     

Urinary monoamine metabolites as indices of mental stress in healthy males and females

Concentrations of the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), the dopamine metabolite homovanillic acid (HVA) and the noradrenaline metabolite 4-hydroxy-3-methoxyphenyl glycol (HMPG) were determined in urine samples from healthy male and female students by mass fragmentography. Urine samples were obtained after a demanding examination (mental stress) and a day of ordinary school work (control condition). Self-ratings were obtained of feelings induced by the examination, and of habitual psychosomatic symptoms. The results for both sexes showed that the examination stress induced a significant increase of HVA and HMPG excretion, but not of 5-HIAA. The males excreted significantly more of each of the metabolites than the females. The pattern of correlations between metabolite levels and psychological and psychosomatic variables were strikingly different for the two sexes.     

Antigenic structure of the hexacosapeptide melittin: evidence for three determinants, one with a helical conformation.

ELISA-based epitope analysis was performed using rabbit polyclonal antisera against melittin. Antigenic sites were found at the C-terminus, in the middle section and within the N-terminal helix. Antibodies against the helical segment could discriminate between two faces of the amphiphilic helix. The antigenic sites include the bulk of the melittin hexacosapeptide, which is synonymous with a very high epitope density.