Biomedical subjects

Bernd Niggemann

Publications and source records attributed to Bernd Niggemann.

16 recordsLinked to original sources

PubMed2006

The norepinephrine-driven metastasis development of PC-3 human prostate cancer cells in BALB/c nude mice is inhibited by beta-blockers.

The development of metastases is a decisive step in the course of a cancer disease. The detection of metastases in cancer patients is correlated with a poor prognosis, and over 90% of all deaths from cancer are not due to the primary tumor, which often can be successfully treated, but are due to the metastases. Tumor cell migration, a prerequisite for metastasis development, is not merely genetically determined, but is distinctly regulated by signal substances of the environment including chemokines and neurotransmitters. We have shown previously that the migration of breast, prostate, and colon carcinoma cells is enhanced by the stress-related neurotransmitter norepinephrine in vitro, and that this effect can be inhibited by the beta-blocker propranolol. We now provide for the first time evidence for the in vivo relevance of this neurotransmitter-driven regulation using PC-3 prostate carcinoma cells. The development of lumbar lymph node metastases in athymic BALB/c nude mice increased with the application of norepinephrine via microosmotic pumps, while propranolol inhibited this effect. However, the growth of the primary tumor was not affected by either treatment. Additionally, experiments using human tissue microarrays showed that 70-90 percent of breast, colon, and prostate carcinoma tissues express the relevant beta2-adrenoceptor. Thus, our work contributes to the understanding of the basic cellular mechanisms of metastasis development, and furthermore delivers a rationale for the chemopreventive use of clinically established beta-blockers for the inhibition of metastases.

Adrenergic beta-Antagonists↗

PubMed2006

Phosphatidylinositol 3-kinase in the G protein-coupled receptor-induced chemokinesis and chemotaxis of MDA-MB-468 breast carcinoma cells: a comparison with leukocytes.

The polarization of tumor cells and leukocytes into a front end and a rear end is a crucial prerequisite for their autonomous, directed movement. Phosphatidylinositol 3-kinase (PI3K) is assumed to play an important role in this polarization process, whereas the results obtained with different cell types and different migration assays widely vary. Thus, we conducted a comparative study on the role of the PI3K in the locomotor activity and directionality of the migration of tumor cells on the example of MDA-MB-468 breast carcinoma cells in comparison with CTLs and neutrophil granulocytes. We used our well-established, collagen-based, three-dimensional migration assay for the investigation of the chemokinesis and chemotaxis of these cells. Our results show that the role of the PI3K in the regulation of migratory activity is distinct between the investigated cell types: the migration of CTLs and MDA-MB-468 cells was impaired by the inhibition of the PI3K with wortmannin, whereas neutrophil granulocytes were only slightly affected. However, neither cell type was impaired in the ability to respond chemotactically to gradients of ligands to G protein-coupled receptors. Thus, the PI3K contributes to the regulation of migratory activity but not to the directionality of migration of MDA-MB-468 breast carcinoma cells. As a further conclusion with regard to cancer treatment, the PI3K is not a suitable target for the inhibition of metastasis formation, because the migration of leukocytes is also affected, which leads to a dysfunction of the immune defense.

Breast Neoplasms↗

PubMed2006

Carcinogenesis driven by bone marrow-derived stem cells.

The overall mechanism of bone marrow-derived stem cell (BMDC) trans-differentiation seems to be simple: BMDCs trans-differentiate as referred to the blueprint, which is given by the tissue itself. Thereby, the blueprint can be the local tissue micro-environment (defined by the tissue-specific cytokine, chemokine, adhesion molecule pattern, etc.), it can be a single cell (cell fusion), or it can be a combination of both. In fact stem cell trans-differentiation is a complex not yet fully understood process. In between the start- and stop-points of transdifferentiation several gene reprogramming steps have to occur in a sequential step-by-step manner, for which a defined set of instructions is a prerequisite to ensure an accurate transdifferentiation. However, a recent study indicated that the ability of BMDCs - to adopt tissue function by reading its blueprint - seems to be a double-edged sword since BMDCs that have received a faulty blueprint, provided by chronically inflamed tissue, trans-differentiated into a neoplastic phenoytpe. Here, we review the importance of an accurate blueprint for BMDC trans-differentiation and discuss a model showing that BMDCs might contribute to overall tumor development due to recruitment to tumor tissue.

Animals↗

PubMed2005

Analysis methods of human cell migration.

The autonomous migration of specialized cells is an essential characteristic in both physiological and pathological functions in the adult human organism. Leukocytes, fibroblasts, and stem cells, but also tumor cells, are thus the subject of intense investigation in a broad range of research fields. A wide spectrum of methods have therefore been established to analyze chemokinetic and chemotactic cell migration, ranging from easy-to-handle two-dimensional surface migration assays to highly specialized three-dimensional and intravital analysis methods. It is now manifest that the results obtained with these various migration assays substantially differ. This review therefore gives an overview of the migration assays which are currently in use, describes the methods, and critically enlightens the particular advantages and disadvantages of each method.

Cell Movement↗

PubMed2005

Role of the beta1-integrin subunit in the adhesion, extravasation and migration of T24 human bladder carcinoma cells.

The abilities of tumor cells to extravasate from the blood vessel system and to migrate through the connective tissue are prerequisites in metastasis formation. Both processes are chiefly mediated by integrins, which mediate both cell-cell and cell-matrix interactions. We investigated the role of integrin subunits in the adhesion, extravasation and migration of the highly invasive human bladder carcinoma cell line T24. Here we show that inhibition of the beta(1)-integrin subunit using the specific beta(1)-integrin blocking antibody 4B4 significantly reduces the adhesion to HUVEC and transmigratory activity of T24 cells. The blockade of the beta(1)-integrin subunit also resulted in a significantly reduced locomotory activity of T24 cells. A detailed cell migration analysis on a single cell level revealed that blockade of the beta(1)-integrin subunit leads to an altered migration pattern of single cells but does not influence migration per se. Migration parameters such as time active, velocity and distance migrated were significantly reduced as compared to untreated control cells. Our observations strongly suggest a central role for the beta(1)-integrin subunit in forming the cell-cell and cell-matrix bonds necessary for adhesion, extravasation and migration.

Carcinoma↗

PubMed2004

Induction of a metastatogenic tumor cell type by neurotransmitters and its pharmacological inhibition by established drugs.

The active migration of tumor cells, a crucial requirement for metastasis development and cancer progression, is regulated by signal substances including neurotransmitters. We investigated the migration of tumor cells within a three-dimensional collagen matrix using time-lapse videomicroscopy and computer-assisted analysis of the migration path. Tumor cell migration is induced by norepinephrine, dopamine and substance P. We show that this induced migration, using MDA-MB-468 breast and PC-3 prostate carcinoma cells, can be inhibited by using specific, clinically established receptor antagonists to the beta2-adrenoceptor, the D2 receptor, or the neurokinin-1 receptor, respectively. All of the investigated neurotransmitters significantly activated the cyclic adenosine-monophosphate response element binding protein (CREB). Furthermore, microarray analysis revealed changes of gene expression toward a highly motile tumor cell type, including an upregulation of the alpha2 integrin, which is an essential adhesion receptor for collagen in migration. The gene for the tumor suppressor gelsolin was downregulated. These 2 critical alterations were confirmed on the protein level by flow-cytometry and immunoblotting, respectively. Neurotransmitters thus induce a metastatogenic tumor cell type by directly regulating gene expression and increased migratory activity, which can be prevented by established neurotransmitter antagonists.

Breast Neoplasms↗

PubMed2004

Tumor cell locomotion: differential dynamics of spontaneous and induced migration in a 3D collagen matrix.

Although great strides have recently been made in elucidating the factors initiating tumor cell migration and the relevant cellular pathways involved, the constituent components of migratory dynamics for individual tumor cell motion have still not been resolved. Utilizing a three-dimensional (3D) collagen assay and computer-assisted, continuous single cell tracking, we investigated the basic parameters for both the spontaneous and norepinephrine-induced migration of highly metastatic MBA-MB-468 breast, PC-3 prostate, and SW 480 colon carcinoma cells. We show that tumor cells do not migrate with uniform migrational structure and speed as previously thought, but rather, the induction of locomotion elicits significant increases in speed, break frequency, and total cell displacement, but decreases in break length and no change in the recruitment of nonlocomotory cells. We furthermore illustrate the corresponding morphological changes of induced tumor cell migration with emphasis on motion in a collagen matrix. These results demonstrate the complexity of tumor cell migration, and the compulsion for incorporating not only knowledge of intracellular pathways, but also fundamental parameters of migratory behavior into any expansive theory of tumor cell migration and metastasis formation. We furthermore establish the analytical methodology of investigating both the stimulation and potential pharmaceutical inhibition of tumor cell migration.

Biological Assay↗

PubMed2004

Anandamide is an endogenous inhibitor for the migration of tumor cells and T lymphocytes.

Cell migration is of paramount importance in physiological processes such as immune surveillance, but also in the pathological processes of tumor cell migration and metastasis development. The factors that regulate this tumor cell migration, most prominently neurotransmitters, have thus been the focus of intense investigation. While the majority of neurotransmitters have a stimulatory effect on cell migration, we herein report the inhibitory effect of the endogenous substance anandamide on both tumor cell and lymphocyte migration. Using a collagen-based three-dimensional migration assay and time-lapse videomicroscopy, we have observed that the anandamide-mediated signals for CD8+ T lymphocytes and SW 480 colon carcinoma cells are each mediated by distinct cannabinoid receptors (CB-Rs). Using the specific agonist docosatetraenoylethanolamide (DEA), we have observed that the norepinephrine-induced migration of colon carcinoma cells is inhibited by the CB1-R. The SDF-1-induced migration of CD8+ T lymphocytes was, however, inhibited via the CB2-R, as shown by using the specific agonist JWH 133. Therefore, specific inhibition of tumor cell migration via CB1-R engagement might be a selective tool to prevent metastasis formation without depreciatory effects on the immune system of cancer patients.

Adrenergic alpha-Agonists↗

PubMed2004

MCP-1 induces migration of adult neural stem cells.

As a model for brain inflammation we previously studied transcriptional profiles of tumor necrosis factor-alpha (TNF)treated U373 astroglioma cells. In previous work we were able to demonstrate that the chemokine monocyte chemoattractant protein-1 (MCP-1, SCYA2, CCL2, MCAF) expression in U373 cells was inducible by TNF-alpha treatment. Demonstrably MCP-1 mRNA and protein expression in U373 cells was sustainable over time and at the highest level of all genes analyzed (Schwamborn et al., BMC Genomics 4, 46, 2003). In the hematopoietic system MCP-1 is a CC chemokine that attracts monocytes, memory T lymphocytes, and natural killer cells. In search of further functions in brain inflammation we tested the hypothesis that MCP-1 acts as a chemokine on neural stem cells. Here we report that MCP-1 activates the migration capacity of rat-derived neural stem cells. The migration of stem cells in a Boyden chamber analysis was elevated after stimulation with MCP-1. Time-lapse video microscopy visualized the migration of single stem cells from neurospheres in MCP-1-treated cultures, whereas untreated cultures depicted no migration at all, but showed signs of sprouting. Expression of the MCP-1 receptor CCR2 in neurosphere cultures was verified by RT-PCR and immunofluorescence microscopy. Supernatants from TNF-treated U373 cells also induced migration of neural stem cells.

Animals↗

PubMed2004

Inhibition of cell migration via G protein-coupled receptors to opioid peptides and angiotensin.

Neurotransmitters are stimulatory as well as inhibitory regulators of cell migration. Angiotensin is such an inhibitory regulator of the SDF-1-induced migration of cytotoxic T lymphocytes, as we have investigated by time-lapse videomicroscopy and computer-assisted cell tracking. For angiotensin II, the most effective form of angiotensin for the inhibition of migration, two G protein-coupled receptors are known, which both downregulate the activity of the adenylyl cyclase via activation of inhibitory G proteins. This downregulation of the enzymatic activity is a key signaling event for the inhibition of T lymphocyte and tumor cell migration, while stimulatory neurotransmitters--for example, norepinephrine--cause an activation of the adenylyl cyclase. Similar to angiotensin, the SDF-1-induced migration of cytotoxic T lymphocytes was inhibited by DAMGO, a specific agonist for the mu-opioid receptor, which is coupled to inhibitory G proteins, too. More interestingly, DAMGO downregulated the met-enkephalin-induced migration of MDA-MB-468 breast carcinoma cells. Met-enkephalin binds to the delta-opioid receptor and, with lower affinity, to the mu-opioid receptor. Since the delta-opioid receptor also activates inhibitory G proteins, the promigratory effect of met-enkephalin is caused by an intracellular signaling distinct from the engagement of each opioid receptor alone. In summary, the dual control of the adenylyl cyclase functions as an integrator of stimulatory and inhibitory signals for T lymphocyte and tumor cell migration, which are delivered by neurotransmitters and other signal substances that bind to G protein-coupled receptors.

Angiotensins↗

PubMed2004

Differential effects of culture conditions on the migration pattern of stromal cell-derived factor-stimulated hematopoietic stem cells.

Evidence is mounting that hematopoietic stem cells (HSCs) play a critical role in bone marrow regeneration and tissue renewal, for which migration is an obvious prerequisite. Computer-aided analysis and a three-dimensional collagen matrix assay enabled us to analyze single-cell migratory characteristics of stromal cell-derived factor-1 alpha (SDF-1 alpha)-stimulated cord blood-derived HSCs. We defined and resolved specific migratory parameters in spontaneous and SDF-1 alpha-induced migration of these cells. The addition of interleukin 6 to the culture medium led to differential SDF-1 alpha-stimulated migratory response, which comprised a recruitment of nonmoving cells and an increase in speed and frequency of pauses but a decrease in pause duration. We were thus able to decipher the exact parameters that result in an increase in the migration of HSCs and demonstrate that extensive analysis of single-cell behavior is elementary in the study of stem cell migration.

AC133 Antigen↗

PubMed2003

Neurotransmitters regulate the migration and cytotoxicity in natural killer cells.

Natural killer (NK) cells and cytotoxic T lymphocytes (CTL), the functional coordination of which are governed by various signal substances, are crucial in the body's defense of tumor and virus-infected cells. We investigated the role of various neurotransmitters and hormones on the regulation of functional parameters, including NK cell cytotoxicity, and the migration of NK cells and CTL within a three-dimensional collagen lattice. Using peripheral blood CTL and NK cells, we show that the neurotransmitters endorphin, histamine and substance P increase NK cell cytotoxicity, while norepinephrine inhibits cytotoxicity. Moreover, substance P reduces migratory activity, while norepinephrine increases NK cell and CTL migration. Furthermore, all three steroid hormones which were investigated, namely cortisone, testosterone, and estradiol, had regulatory influence on both cytotoxicity and migration of NK cells. These results further specify the functional basis of the complex interconnection between the immune and neuro-endocrine systems.

Bombesin↗

PubMed2003

Boswellic acid acetate induces differentiation and apoptosis in highly metastatic melanoma and fibrosarcoma cells.

The aim of the study was to investigate the antitumor and/or preventive effect of BC-4, an isomeric compound isolated from the plant Boswellia carteri Birdw. containing alpha- and beta-boswellic acid acetate in 1:1, MW 498.3. We used the MTT (3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide) assay to study the growth inhibition activity of BC-4. Tumor cells migration within a three-dimensional collagen matrix was recorded by time-lapse videomicroscopy and computer-assisted cell tracking. Topoisomerase II was isolated from mouse melanoma B16F10 cells and its activity was determined by its ability to cut plasmid pBR322 DNA. The secretion and activity of matrix metalloproteinases (MMPs) from human fibrosarcoma HT-1080 cells were determined by gelatin zymography. BC-4 was a cytostatic compound and could induce the differentiation of B16F10 mouse melanoma cells, blocked the cell population in G1 phase and inhibited topoisomerase II activity. The G1 phase population of B16F10 cells was increased from 57.4 to 87.7%, while S phase population was reduced from 33.3 to 5.9% after treatment with BC-4 at 25 microM concentration for 48 h. BC-4 also inhibited the migration activity of B16F10. BC-4 could induce apoptosis of HT-1080 cells, as proved by acridine orange fluorescence staining, Wright-Giemsa staining, electromicroscopy, DNA fragmentation and flow cytometry. BC-4 inhibited the secretion of MMPs from HT-1080 cells, too. In conclusion, if it turns out that BC-4 is a well tolerated substance, exhibiting no significant toxicity or side effects, being evaluated currently in China, BC-4 is a good candidate for the prevention of primary tumor, invasion and metastasis.

Animals↗

PubMed2002

The neurotransmitter gamma-aminobutyric acid is an inhibitory regulator for the migration of SW 480 colon carcinoma cells.

Gamma-aminobutyric acid (GABA) is the inhibitory neurotransmitter in the brain, also playing a role in diseases like epilepsy. We now show that this inhibitory neurotransmitter can also reduce migratory activity in SW 480 colon carcinoma cells. GABA reduced the norepinephrine-induced migratory activity of these cells within a three-dimensional collagen matrix to spontaneous migration levels, as was analyzed by time-lapse videomicroscopy. This inhibitory effect of GABA was mediated by the serpentine receptor GABA(B) and was intracellularly transduced by a decrease of the cyclic AMP concentration. Cancer cell migration is thus regulated by neurobiological signals, opening new possibilities for pharmacological agonists in cancer therapy.

Bucladesine↗

PubMed2002

Induction of cancer cell migration by epidermal growth factor is initiated by specific phosphorylation of tyrosine 1248 of c-erbB-2 receptor via EGFR.

Induction of tumor cell migration is a key step in invasion and metastasis. Here we report that the epidermal growth factor (EGF)-induced cell migration of breast cancer cells is attributed to a transient, rather than a sustained, activation of phospholipase C (PLC)-gamma1 due to c-erbB-2 signaling. EGF stimulation of EGF receptor (EGFR) overexpressing cells resulted in long-term PLC-gamma1 tyrosine phosphorylation and sustained levels of inositol-1,4,5-triphosphate (IP3) and diacylglycerol (DAG) producing sinusoidal calcium oscillations. In contrast, c-erbB-2/EGFR expressing cells displayed baseline transient calcium oscillations after EGF treatment due to short-term PLC-gamma1 tyrosine phosphorylation and short-term IP3 and DAG turnover. A third cell line expressing a point-mutated c-erbB-2 receptor that lacks the autophosphorylation Y1248 was generated to investigate whether the different PLC-gamma1 activation was attributed to this structure. Neither PLC-gamma1 tyrosine phosphorylation nor IP3 and DAG turnover and calcium oscillations were observed in this cell line, indicating the modulation of the PLC-g1 activation time course by c-erbB-2 signaling. Induction of cell migration was solely observable in the c-erbB-2-positive cell line as proved by the mode of actin reorganization and a cell migration assay, using a 3D-collagen lattice. In summary, c-erbB-2 up-regulation switches on the cell migration program by modulating the time course of PLC-gamma1 activation.

Calcium↗

PubMed2002

Signal processing in migrating T24 human bladder carcinoma cells: role of the autocrine interleukin-8 loop.

T24 human bladder carcinoma cells reveal a high locomotor activity (70% locomoting cells) within a 3-dimensional collagen matrix. This high migratory activity is induced by an autocrine engagement of the interleukin-8 receptor A, as was shown by antibodies neutralizing the secreted interleukin-8. Treatment of the cells with these specific antibodies reduced the locomotor activity by half. The intracellular signal transduction underlying the interleukin-8-induced T24 locomotion involves the activity of protein tyrosine kinases (PTKs), the phospholipase Cgamma (PLCgamma) and the protein kinase C (PKC), as proven by the use of specific enzyme inhibitors. These results suggest the following model for the regulatory signal transduction of interleukin-8-induced human T24 bladder carcinoma cell migration: The engagement of the interleukin-8-receptor, a receptor of the serpentine family, leads to the beta-arrestin-mediated activation of PTKs. These kinases phosphorylate the PLCgamma, which generates the second messengers diacylglycerol (DAG) and inositol-1,4,5-trisphosphate (IP(3)). DAG activates the PKC, whereas IP(3) mediates the release of calcium from the endoplasmatic reticulum. By means of confocal laser microscopy, we observed an oscillation of the cytosolic calcium concentration in migrating T24 cells, which were loaded with the calcium-dye fluo-3/AM. Here, we report on a new autocrine function of secreted interleukin-8 and the intracellular signal transduction leading to the regulation of cytosolic calcium and to a migratory tumor cell phenotype.

Antibodies↗