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Biomedical subjects

K Bjørnland

Publications and source records attributed to K Bjørnland.

16 recordsLinked to original sources
PubMed2003

Modulation of glioma cell invasion and motility by adenoviral gene transfer of PAI-1.

A number of studies have emphasized the role of PAI-1 as an important regulator of tumor cell invasion and metastasis. The hallmark of primary tumors of the central nervous system and glioblastomas in particular is the diffuse invasion into the normal brain tissue. Since PAI-1 is expressed in such tumors, we studied the effect of adenoviral-mediated transfer of the PAI-1 gene in regulating the in vitro invasiveness of D54Mg glioma cells into Matrigel, and into fetal rat brain aggregates. Treatment of D54Mg cells with 50 MOI (multiplicity of infection) of the replication defective vector AdCMVPAI-1 increased PAI-1 expression 23-fold compared to control vectors, and the invasion through Matrigel was reduced by 67%. The motility of the cells was reduced by 58% compared to controls (indicating that inhibition of motility was the principal effect of PAI-1 in these cells). The ability of D54Mg tumor spheroids to invade fetal rat brain aggregates was not reduced by the PAI-1 gene transfer. The results show that overexpression of PAI-1 can inhibit glioma cell motility and invasion through extracellular matrix (ECM) components, like laminin and collagen, but does not inhibit tumor cell invasion in a three-dimensional invasion assay, simulating normal brain tissue having a different ECM and interstitial composition. The different results obtained in the two invasion assays reflect the complex biological effects of the uPA/PAI-1 system, and questions a simplistic view of PAI- I as an inhibitor of brain tumor invasion.

Adenoviridae↗
PubMed2001

Expression of matrix metalloproteinases and the metastasis-associated gene S100A4 in human neuroblastoma and primitive neuroectodermal tumor cells.

BACKGROUND: Matrix metalloproteinases (MMPs) and their endogenous inhibitors (tissue inhibitors of MMPs; TIMPs) have been shown to correlate with in vitro invasiveness and clinical outcome in several adult malignancies. The importance of MMP and TIMP expression in neuroblastoma (NB) and primitive neuroectodermal tumors (PNET) is incompletely understood. The aim of the current study was to relate in vitro invasion of NB and PNET cell lines with MMP and TIMP expression and evaluate the effect of a synthetic MMP inhibitor. Furthermore, S100A4 levels were determined because recent reports have suggested a possible association between MMPs, TIMPs, and the metastasis-associated gene S100A4. METHODS: Expression of MMPs, TIMPs, and S100A4 was evaluated at both mRNA and protein levels in 2 human NB and 2 PNET cell lines. In vitro invasion and effects of the synthetic MMP inhibitor Marimastat were assessed in the Transwell chamber assay. RESULTS: The most invasive cells expressed the highest levels of MMPs and S100A4. Marimastat reduced invasion by 30%. CONCLUSIONS: In vitro invasion correlated with MMP and S100A4 expression. The fact that Marimastat reduced in vitro invasion is encouraging for further studies on a possible therapeutic application for proteinase inhibitors.

Blotting, Northern↗
PubMed2001

Are patients with Hirschsprung's disease prediabetic?

Hirschsprung's disease (HD) is considered a focal disease usually confined to the distal colon and rectum. However, autonomic dysfunction and dysmotility in the upper gastrointestinal tract have been reported, suggesting that this disease is not only confined to the distal gastrointestinal tract. This study examines the fasting and postprandial levels of glucose and insulin in adult patients with HD to elucidate whether there might also be an endocrine involvement in this disease. Sixteen patients with surgically treated HD during early childhood and 17 healthy subjects were studied. All subjects ingested a caloric liquid meal containing glucose, lactose, maize oil, and water (2,020 kJ) after an overnight fast. Blood samples were collected at regular intervals for insulin and glucose analyses. Fasting levels of both glucose (P <.05) and insulin (P <.02) were significantly higher in patients compared with healthy controls. Peak concentration of insulin following meal intake was significantly higher in the patient group (P <.05), and peak concentration of glucose tended to be higher in patients compared with controls (P =.06). There was no correlation between body mass index and serum levels of glucose or insulin. The present study shows that adult patients treated for HD during childhood have an impaired glucose and insulin homeostasis, indicating a mild degree of insulin resistance. This may imply susceptibility towards development of non-insulin-dependent diabetes mellitus.

Adolescent↗
PubMed1999

S100A4 involvement in metastasis: deregulation of matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases in osteosarcoma cells transfected with an anti-S100A4 ribozyme.

The biological function of the metastasis-associated gene S100A4 is not fully understood, although there is evidence indicating interactions between the gene product and the cytoskeleton. We have examined whether an association could exist between S100A4 and the regulation of matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs). For these studies, three clones of a highly metastatic human osteosarcoma cell line (OHS) transfected with a hammerhead ribozyme directed against the S100A4 gene transcript were used. The clones demonstrated different expression levels of S100A4 and also different metastatic capacity. In the clone with the most prominent down-regulation of S100A4, the mRNA levels of MMP2, membrane type (MT) 1-MMP, and TIMP-1 were significantly reduced in exponentially growing cultures. Western blots, gelatin zymography, and ELISA showed similar expression patterns of MMPs and TIMPs at the protein level. In the clones with an intermediate expression of S100A4, reduced expression of MT1-MMP and TIMP-1 was detected, whereas the expression of MMP-2 was at the same level as in the control cells. In contrast to the other factors, TIMP-2 was up-regulated in all of the clones independent of the extent of ribozyme-induced down-regulation of S100A4. The transwell chamber assay demonstrated that the capacity of the ribozyme-transfected cells to cross uncoated filters was reduced, relative to control cells, according to the reduction in the S100A4 expression level. The clone with the lowest reduction in S100A4 did not demonstrate different motility compared with control cells, whereas transfectants with only 5% S100A4 mRNA showed a 50% reduction in motility. Interestingly, this trend was even more striking when the capacity to cross Matrigel-coated filters was analyzed, as all the clones demonstrated between 40 and 75% reduced invasion. It is concluded that S100A4 may exert its effect on metastasis formation not only by stimulating the motility of tumor cells but also by affecting their invasive properties through influencing the expression of MMPs and their endogenous inhibitors.

Bone Neoplasms↗
PubMed1998

Regulation of tissue-degrading factors and in vitro invasiveness in progression of breast cancer cells.

Hormone-independent growth and invasiveness represent phenotypic properties acquired during early progression of breast cancer. We compared human mammary adenocarcinoma cells, MCF-7, which are estrogen-dependent and poorly metastatic, with the estrogen-independent and highly metastatic subline, MCF7/LCC1, with regard to expression of tissue-degrading factors of the matrix metalloproteinase (MMP)-and urokinase (uPA)-dependent degradative pathways, as well as for their in vitro invasive properties. Both cell lines showed low constitutive mRNA expression of the MMP inhibitor TIMP-1. Baseline expression of TIMP-2 mRNA was also very low in MCF-7 cells, whereas the MCF7/LCC1 level was much higher (approximately 10-fold). Furthermore, both cell lines revealed low constitutive capacity to migrate in an in vitro invasion assay. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA; 100 nM) induced the mRNAs for TIMP-1 as well as for MMP-1, MMP-9, the uPA receptor, and the uPA inhibitor PAI-1, amongst which only the responses of MMP-9 and PAI-1 were cell-specific. The mRNA levels of MMP-9 and PAI-1 were approximately 10-fold and approximately 15-fold higher in MCF7/LCC1 cells compared to MCF-7 cells. The secretion of immunoreactive PAI-1 was considerably elevated (> 20-fold) in TPA-treated MCF7/LCC1 cells, whereas the TPA-dependent level of 92-kDa MMP-9 was only approximately 2-fold higher in MCF7/LCC1 cells than in MCF-7 cells. In both cell lines treatment with TPA was associated with an increase (approximately 10-fold) in in vitro migration, which in the MCF7/LCC1 cells was significantly attenuated by a reconstituted basement membrane extract (Matrigel). These data suggest that TPA-responsive in vitro invasive properties that are probably associated with PAI-1 expression may co-vary with progression from hormone-dependent to -independent breast cancer.

Breast Neoplasms↗
PubMed1998

Polymorphonuclear elastase in human colorectal carcinoma.

proteinases are required for invasion through the extracellular matrix (ECM) during tumor invasion and metastasis. Polymorphonuclear (PMN) elastase can degrade ECM components and modulate other proteinases. In the present study PMN elastase activity was found in tissue extracts from 8 of 15 human colorectal carcinomas. Immunoreactive PMN elastase was demonstrated in all carcinoma biopsies with particular enrichment at the tumor-host interface. Immunofluorescence staining localized immunoreactive PMN elastase mainly to neutrophile granulocytes. The human colon carcinoma cell lines Caco-2 and HT-29 did not express PMN elastase. An interaction between tumor cells and elastase producing leukocytes is suggested.

Adenocarcinoma↗
PubMed1998

Human hepatoma cells rich in P-glycoprotein display enhanced in vitro invasive properties compared to P-glycoprotein-poor hepatoma cells.

Whether the phenotypes of drug resistance and metastatic activity in cancer are dependent on each other or not is controversial. We compared in vitro invasive properties of human hepatoma cells resistant to epirubicin and rich in P-glycoprotein (Pgp) (HB8065/R) with the parental epirubicin-sensitive, Pgp-poor cells (HB8065/S). The HB8065/R cells displayed elevated capacity to migrate in a transwell chamber assay (three- to fourfold compared to the HB8065/S cells), both in the absence and presence of a reconstituted basement membrane extract (Matrigel). In the presence of the P-gp inhibitor PSC 833 (1.5 micrograms/ml) the capacity of the HB8065/R cells to cross Matrigel-coated filters was attenuated by approximately 25%. Compared to the HB8065/S cells, the resistant cell line expressed higher level of plasminogen activator inhibitor (PAI)-1 mRNA (approximately threefold), which was reflected by a approximately fivefold increase in secreted PAI-1 immunoactivity (approximately 50 ng/10(6) HB8065/R cells). Furthermore, treatment with PSC 833 was associated with upregulation of PAI-1 mRNA (approximately 3.5-fold) and immunoactivity (approximately twofold) in the HB8065/R cells. Level of tissue inhibitor of metalloproteinases (TIMP)-1 was also significantly increased in the HB8065/R cells compared to the HB8065/S cells, whereas both cell lines showed low constitutive expression of TIMP-2. Levels of TIMPs were not altered by PSC 833. These data suggest that overexpression of Pgp in these hepatoma cells may covariate with the phenotypes of both enhanced in vitro invasiveness and high PAI-1 expression, whether randomly acquired or not.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1997

Bowel function, mental health, and psychosocial function in adolescents with Hirschsprung's disease.

Congenital intestinal malformations are uncommon and may pose lasting somatic difficulties. Patients with anorectal anomalies have a high frequency of persistent faecal dysfunction and psychosocial problems. This study examined whether adolescents with Hirschsprung's disease have more psychosocial problems than their healthy peers. Nineteen adolescents (mean age 15.7 years) with Hirschsprung's disease were assessed for bowel function, anorectal physiology, mental health, and psychosocial functioning by physical examinations, semistructured interview, and standardised questionnaires. The adolescents were compared with controls. The parents of 13 adolescents with Hirschsprung's disease were interviewed and completed questionnaires. Thirty two per cent of the adolescents with Hirschsprung's disease had significant impairment of continence, but no more psychopathology (16%) nor psychosocial dysfunction as a group than their healthy peers. Faecal incontinence was associated with poorer psychosocial functioning and parental criticism. The fact that a significant number of patients with Hirschsprung's disease have incontinence into adulthood indicates the need for parental counselling, encouraging realistic expectations about continence.

Adolescent↗
PubMed1991

Acute abdominal pain as presenting symptom in lymphangiomyomatosis. Case report.

A case of lymphangiomyomatosis presenting with acute abdominal pain is described. Laparotomy revealed a multiloculated cystic mass on the posterior abdominal wall with typical histological pattern. In the ensuing 3 years the respiratory manifestations of this rare disorder have slowly progressed. Possible causal factors and management are discussed.

Abdominal Neoplasms↗
PubMed1990

[Cancer of the pancreatic head and the periampullary region].

Between 1976 and 1988, 16 patients underwent a Whipple resection or total pancreatectomy for carcinoma of the head of the pancreas, the ampulla of Vater or the distal common bile duct. Nine patients had carcinoma of the pancreas. Two of these patients are long-term survivors. The tumors in these patients were highly differentiated and localized close to the common bile duct. Four had ampullary lesions, and are all alive today. Three patients had carcinoma of the common bile duct. One of these patients is alive.

Aged↗
PubMed1989

[Self examination of the breasts].

Self-examination of the breasts is common among women from 24 to 70 years of age. This information was obtained from a study conducted on 600 women. They were asked 12 questions concerning self-examination of breasts. 37.3% examined their breasts once a month or more frequently, while 32.3% performed self-examination only irregularly. 191 found self-examination difficult, and 165 said that they forgot to examine themselves regularly. 60% of the women interviewed wanted more instruction in self-examination of breasts.

Adult↗
PubMed1988

Vesicular stomatitis virus infection enhances invasiveness of Salmonella typhimurium.

When mouse fibroblast L-929 cells were pre-infected with vesicular stomatitis virus, an enhancement of invasiveness by Salmonella typhimurium was observed. The effect was more pronounced when higher virus doses were used. Short-time (5 h) pre-incubation with virus caused a moderate enhancement of invasiveness. When virus pre-incubation time was increased to 8 h or 13 h, a further enhancement was observed. Results obtained after pre-incubation with UV inactivated virus were similar to that achieved by the short-time pre-incubation with the corresponding viable virus preparation. This indicates (i) an early phase of virus infection, when virus causes enhancement of invasiveness that is not dependent on viral nucleic acid induced metabolism, and (ii) a later phase, when virus-induced metabolism is necessary for the enhancement. When virus and bacteria were given concomitantly to infant mice, lethality was increased compared to groups that only received virus or bacteria. The data indicate that vesicular stomatitis virus aggravates infection with a facultatively intracellular bacterium, partly by enhancing the invasiveness of the bacteria.

Animals↗
PubMedDate not supplied

Expression and release of plasminogen activators, their inhibitors and receptor by human tumor cell lines.

Plasminogen activators (PAs) and their inhibitors (PAIs) can be produced by tumor cells and surrounding inflammatory cells and fibroblasts. The present study evaluate both the expression and release of PAs (uPA and tPA) and PAIs (PAI-1 and PAI-2) from cultured cells, and also the expression of uPA receptor (uPAR). Immunocytochemistry showed that PAs, PAIs and uPAR were present to different extents on the surface of colon carcinoma cells (Caco-2, HT-29), malignant melanoma cells (LOX) and normal fibroblasts. uPA immunoreactivity was intermediate in Caco-2, HT-29 and LOX and weak in the fibroblasts. tPA immunoreactivity was intermediate in Caco-2 and LOX and weak in HT-29 and fibroblasts. PAI-1 and PAI-2 immunoreactivities were absent in HT-29, weak in Caco-2 and strong in fibroblasts. In LOX the immunoreactivity was intermediate for PAI-1 and strong for PAI-2. uPAR immunoreactivity was weak in Caco-2, HT-29 and LOX and negative in fibroblasts. ELISAs on conditioned medium detected that the colon carcinoma cells Caco-2 and HT-29 did not release any PAs or PAIs. LOX released tPA (median 9 ng/million cells at 72 hours), PAI-1 (1050 ng/million cells) and PAI-2 (245 ng/million cells), and fibroblasts released uPA (1 ng/million cells) and PAI-1 (910 ng/million cells). These results show that both tumor cells and fibroblasts express tissue destructive enzymes, PAs and PAIs, whereas only the tumor cells express the uPAR required for focalization and regulation of PA activity at the cell surface. The melanoma cells LOX and fibroblasts also released PAs and PAIs, in contrast to the colon carcinoma cells Caco-2 and HT-29.

Cell Line↗
PubMedDate not supplied

Cysteine proteinase inhibitors reduce malignant melanoma cell invasion in vitro.

Proteolytic enzymes are believed to be necessary for tumor cell invasion. We have studied the effects of the cysteine proteinase inhibitor E-64 and the serine and cysteine proteinase inhibitor leupeptin, on the ability of human malignant melanoma cells (LOX) to pass through an artificial basement membrane. Transwell chambers containing filters coated with the reconstituted basement membrane, Matrigel, were used. Nontoxic concentrations of the proteinase inhibitors reduced the invasion of LOX cells through Matrigel. E-64 (250 mumol/l) by 27% and leupepetin (250 micrograms/ml) by 46%. The proteinase inhibitors did not alter the growth rate of the tumor cells, their motility through uncoated filters, or their attachment to the Matrigel coated wells. Our results indicate that cysteine proteinases are involved in the degradation of basement membranes and thus contribute to the invasion of malignant melanoma cells.

Animals↗