Expression of adhesion receptor integrin ␣v3 in an activated functional form strongly promotes metastasis in human breast cancer cells. Here, we report that ␣v3 cooperates with matrix metalloproteinase type 9 (MMP-9) in breast cancer cell migration. This cooperation is regulated by the activation state of the integrin. Expression of activated ␣v3 in metastatic variants of MDA-MB 435 human breast cancer cells and primary metastatic cells from breast cancer patients strongly enhanced migration toward vitronectin and fibrinogen. This enhancement was mediated by a soluble factor produced by breast cancer cells expressing activated ␣v3. When transferred, this factor also up-regulated ␣v3-dependent migration of breast cancer cells that express the nonactivated integrin. The factor was identified as metalloproteinase MMP-9. Whereas all tested breast cancer cell variants produced latent MMP-9, only those with activated ␣v3 produced the mature form of this metalloproteinase. Recombinant mature MMP-9, but not latent MMP-9 or either form of MMP-2, enhanced ␣v3-dependent breast cancer cell migration. The migratory response was inhibited by tissue inhibitors of metalloproteinase or when MMP-9 was depleted from the inducing supernatants. The results indicate a causal relationship between the expression of activated integrin ␣v3 and production of enzymatically active MMP-9 in metastatic breast cancer cells. These molecules cooperate to enhance breast cancer cell migration toward specific matrix proteins, and this may contribute to the strongly enhanced metastatic capacity of breast cancer cells that express activated ␣v3.M etastasis is the primary cause of death in breast cancer patients. Metastatic dissemination depends on tumor cell adhesion, migration, and invasion. These steps involve integrins, a family of transmembrane adhesion receptors, composed of noncovalently linked ␣ and  subunits (1). Integrins are known to exist in distinct states of activation, and these determine integrin functionality and affinity for ligands (2). For example, integrin activation controls which ligands are recognized, whether an integrin can support cell arrest under dynamic flow conditions or only stationary adhesion, and whether cells can migrate on or toward specific substrates (3). The importance of integrin activation has long been appreciated in leukocytes and platelets, where it controls inflammatory responses and thrombus formation (4, 5). Recent findings indicate that other cell types, such as endothelial cells and tumor cells, can also regulate their interaction with extracellular matrix proteins by integrin activation (6-9). This regulation may help to control angiogenesis and tumor metastasis.In breast and ovarian cancer, as well as in melanoma and glioma, malignant progression is associated with expression of tumor cell integrin ␣v3 (10-14). We recently found that ␣v3 can exist in human breast cancer cells in an activated or a nonactivated functional state. Only the activated state supports breast cancer cell arrest du...
Hydroalcoholic hypericum extract inhibits the synaptosomal uptake of serotonin, norepinephrine, and dopamine with about similar affinities and leads to a significant down-regulation of cortical beta-adrenoceptors and 5-HT2-receptors after subchronic treatment of rats. While neither hypericine nor kaempferol did show any reuptake inhibiting properties, hyperforin was identified as the unspecific reuptake inhibitor of hypericum extracts with half-maximal inhibitory concentrations for the three synaptosomal uptake systems mentioned above between 80 and 200 nmol/l. Moreover, a hyperforin-enriched (38%) CO2 extract also leads to a significant beta-receptor down-regulation after subchronic treatment. The data suggest hyperforin as the active principle of hypericum extracts in biochemical models of antidepressant activity.
Since the mechanism of the antidepressant activity of hypericum extract is not yet understood, we tested possible effects of standardized hypericum extract (LI 160) in several biochemical models relevant for the mechanism of action of other antidepressant drugs. While LI 160 was only a weak inhibitor of MAO-A and MAO-B activity, it inhibited the synaptosomal uptake of serotonin, dopamine and norepinephrine with about equal affinity-2 micrograms/ml). Moreover, subchronic treatment of rats with hypericum extract led to a significant down-regulation of beta-receptors and to a significant up-regulation of 5-HT2-receptors in the frontal cortex. The data might suggest that hypericum extract acts via similar biochemical mechanisms to other antidepressants (e.g. tricyclics).
This large population-based study suggests that participants receiving an estradiol transdermal system have a significantly lower incidence of venous thromboembolism than do participants receiving oral estrogen-only hormone therapy.
Objective:
The aim of this study was to quantify the magnitude of risk reduction for venous thromboembolism events associated with an estradiol transdermal system relative to oral estrogen-only hormone therapy agents.
Methods:
A claims analysis was conducted using the Thomson Reuters MarketScan database from January 2002 to October 2009. Participants 35 years or older who were newly using an estradiol transdermal system or an oral estrogen-only hormone therapy with two or more dispensings were analyzed. Venous thromboembolism was defined as one or more diagnosis codes for deep vein thrombosis or pulmonary embolism. Cohorts of estradiol transdermal system and oral estrogen-only hormone therapy were matched 1:1 based on both exact factor and propensity score matching, and an incidence rate ratio was used to compare the rates of venous thromboembolism between the matched cohorts. Remaining baseline imbalances from matching were included as covariates in multivariate adjustments.
Results:
Among the matched estradiol transdermal system and oral estrogen-only hormone therapy users (27,018 women in each group), the mean age of the cohorts was 48.9 years; in each cohort, 6,044 (22.4%) and 1,788 (6.6%) participants had a hysterectomy and an oophorectomy at baseline, respectively. A total of 115 estradiol transdermal system users developed venous thromboembolism, compared with 164 women in the estrogen-only hormone therapy cohort (unadjusted incidence rate ratio, 0.72; 95% CI, 0.57-0.91; P = 0.006). After adjustment for confounding factors, the incidence of venous thromboembolism remained significantly lower for estradiol transdermal system users than for estrogen-only hormone therapy users.
Conclusions:
This large population-based study suggests that participants receiving an estradiol transdermal system have a significantly lower incidence of venous thromboembolism than do participants receiving oral estrogen-only hormone therapy.
peutic intervention and trial monitoring and outcome evaluation. Complicating this situation is inconsistencies in CFS case definition. The main objective is to provide a critical review of the similarities and differences between the varying approaches to CFS case definition. The conflicts and controversies that have emerged as a result of the differing definitional criterion for CFS are highlighted and the potential impact on future research is identified. A critical review of the most frequently used case definitions in CFS was conducted. There are currently five case definitions of CFS; however, the most prominent is the 1994 Centre for Disease Control and Prevention Case Definitions. However, prima face comparative advantages of this definition are elusive and indeed, it has been widely criticized for its lack of specificity. Counterintuitively, there is little compelling evidence to support the efficacy of any of the case definitions have produced evidence to demonstrate their accuracy or precision at defining cases of CFS. A summary description of the symptom profile for each of the case definitions is provided. The inconsistencies that have emerged in CFS research as a consequence of differing approaches to case definition are contrasted and discussed. Clinical and research implications are highlighted.
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