Retraction of mesenchymal stromal cells supports the invasion of colorectal cancer cells (CRC) into the adjacent compartment. CRC-secreted 12(S)-HETE enhances the retraction of cancer-associated fibroblasts (CAFs) and therefore, 12(S)-HETE may enforce invasivity of CRC. Understanding the mechanisms of metastatic CRC is crucial for successful intervention.
View Article and Find Full Text PDFSecretion of 12(S)-HETE by breast cancer emboli provokes "circular chemorepellent induced defects" (CCIDs) in the adjacent lymphatic vasculature facilitating their intravasation and lymph node metastasis which determines prognosis. Therefore, elucidating the mechanism of lymph endothelial cell (LEC) wall disintegration may provide cues for anti-metastatic intervention. The role of intracellular free Ca(2+) for CCID formation was investigated in LECs using MCF-7 or MDA-MB231 breast cancer cell spheroids in a three-dimensional cell co-culture model.
View Article and Find Full Text PDFEpigallocatechin gallate (EGCG), ellagic acid (EA) and rosmarinic acid (RA) are natural polyphenols exerting cancer chemopreventive effects. Ribonucleotide reductase (RR; EC 1.17.
View Article and Find Full Text PDFThe contribution of organic anion transporting polypeptides (OATPs) to the cellular uptake of flavopiridol was investigated in OATP1B1-, OATP1B3- and OATP2B1-expressing Chinese hamster ovary (CHO) cells. Uptake of flavopiridol into these cells showed typical Michaelis-Menten kinetics with much higher transport capacity for OATP1B3 compared to OATP1B1 and OATP2B1 (Vmax/Km, 33.9 vs.
View Article and Find Full Text PDFScope: Resveratrol is a naturally occurring polyphenolic compound with various pharmacological activities. These effects are observed despite its low bioavailability, which is particularly caused by extensive phase II metabolism. It is unknown whether resveratrol and its metabolites can accumulate to bioactive levels in organs and tissues through protein-mediated transport mechanisms.
View Article and Find Full Text PDFMetastatic breast cancer is linked to an undesired prognosis. One early and crucial metastatic step is the interaction of cancer emboli with adjacent stroma or endothelial cells, and understanding the mechanisms of this interaction provides the basis to define new targets as well as drugs for therapy and disease management. A three-dimensional (3D) co-culture model allowing the examination of lymphogenic dissemination of breast cancer cells was recently developed which facilitates not only the study of metastatic processes but also the testing of therapeutic concepts.
View Article and Find Full Text PDFBackground: Breast cancer is the leading cause of cancer death in women living in the western hemisphere. Despite major advances in first-line endocrine therapy of advanced oestrogen receptor (ER)-positive breast cancer, the frequent recurrence of resistant cancer cells represents a serious obstacle to successful treatment. Understanding the mechanisms leading to acquired resistance, therefore, could pave the way to the development of second-line therapeutics.
View Article and Find Full Text PDFDigalloylresveratrol (DIG) is a recently synthesized substance aimed to combine the effects of the natural polyphenolic compounds gallic acid and resveratrol, which both are excellent free radical scavengers with anticancer activity. In this study, we investigated the effects of DIG in the human AsPC-1 and BxPC-3 pancreatic adenocarcinoma cell lines. Treatment with DIG dose-dependently attenuated cells in the S phase of the cell cycle and led to a significant depletion of the dATP pool in AsPC-1 cells.
View Article and Find Full Text PDFMetastases destroy the function of infested organs and are the main reason of cancer-related mortality. Heteronemin, a natural product derived from a marine sponge, was tested in vitro regarding its properties to prevent tumour cell intravasation through the lymph-endothelial barrier. In three-dimensional (3D) cell cultures consisting of MCF-7 breast cancer cell spheroids that were placed on lymph-endothelial cell (LEC) monolayers, tumour cell spheroids induce "circular chemorepellent-induced defects" (CCIDs) in the LEC monolayer; 12(S)-Hydroxyeicosatetraenoic acid (12(S)-HETE) and NF-κB activity are major factors inducing CCIDs, which are entry gates for tumour emboli intravasating the vasculature.
View Article and Find Full Text PDFHealth beneficial effects of xanthohumol have been reported, and basic research provided evidence for anti-cancer effects. Furthermore, xanthohumol was shown to inhibit the migration of endothelial cells. Therefore, this study investigated the anti-metastatic potential of xanthohumol.
View Article and Find Full Text PDFBackground: As metastasis is the prime cause of death from malignancies, there is vibrant interest to discover options for the management of the different mechanistic steps of tumour spreading. Some approved pharmaceuticals exhibit activities against diseases they have not been developed for. In order to discover such activities that might attenuate lymph node metastasis, we investigated 225 drugs, which are approved by the US Food and Drug Administration.
View Article and Find Full Text PDFThe present study investigates extracts of Neuolaena lobata, an anti-protozoan ethnomedicinal plant of the Maya, regarding its anti-neoplastic properties. Firstly, extracts of increasing polarity were tested in HL-60 cells analyzing inhibition of cell proliferation and apoptosis induction. Secondly, the most active extract was further tested in anaplastic large cell lymphoma (ALCL) cell lines of human and mouse origin.
View Article and Find Full Text PDFBackground: Many cancers spread through lymphatic routes, and mechanistic insights of tumour intravasation into the lymphatic vasculature and targets for intervention are limited. The major emphasis of research focuses currently on the molecular biology of tumour cells, while still little is known regarding the contribution of lymphatics.
Methods: Breast cancer cell spheroids attached to lymphendothelial cell (LEC) monolayers were used to investigate the process of intravasation by measuring the areas of 'circular chemorepellent-induced defects' (CCID), which can be considered as entry gates for bulky tumour intravasation.
Pancreas cancer cells escape most treatment options. Heat shock protein (Hsp)90 is frequently over-expressed in pancreas carcinomas and protects a number of cell-cycle regulators such as the proto-oncogene Cdc25A. We show that inhibition of Hsp90 with geldanamycin (GD) destabilizes Cdc25A independent of Chk1/2, whereas the standard drug for pancreas carcinoma treatment, gemcitabine (GEM), causes Cdc25A degradation through the activation of Chk2.
View Article and Find Full Text PDFPlants have been the source of several effective drugs for the treatment of cancer and over 60% of anticancer drugs originate from natural sources. Therefore, extracts of the rhizome of Smilax spinosa, an ethnomedicinal plant from Guatemala which is used for the treatment of inflammatory conditions, were investigated regarding their anti-neoplastic activities. By using several solvents the methanol extract was by far the most potent against HL60 cell proliferation (50% inhibition at 60 µg/ml).
View Article and Find Full Text PDFEvid Based Complement Alternat Med
August 2012
Introduction. Several studies demonstrated that anti-inflammatory remedies exhibit excellent anti-neoplastic properties. An extract of Pluchea odorata (Asteraceae), which is used for wound healing and against inflammatory conditions, was fractionated and properties correlating to anti-neoplastic and wound healing effects were separated.
View Article and Find Full Text PDFInvestigating the bioactivity of traditional medical remedies under the controlled conditions of a laboratory is an option to find additional applications, novel formulations or lead structures for the development of new drugs. The present work analysed the anti‑neoplastic activity of increasing polar extracts of the rainforest plant Critonia morifolia (Asteraceae) that has been successfully used as traditional remedy to treat various inflammatory conditions in the long-lasting medical tradition of the Central American Maya, which was here also confirmed in vitro. The apolar petroleum ether extract exhibited the most potent anti‑proliferative and pro‑apoptotic effects in HL‑60 cells and triggered down-regulation of Cdc25C and cyclin D1 within 30 min followed by the inhibition of c-Myc expression and the onset of caspase-3 activation within 2 h.
View Article and Find Full Text PDFDifferent studies describe the anti-inflammatory effects of Scrophularia species, a medicinal plant widely used in folk medicine since ancient times. As knowledge regarding the anti-neoplastic properties of this species is rather limited, we investigated the influence of methanol extracts of different Scrophularia species on cell proliferation, cell death, and tumour cell intravasation through the lymph endothelial barrier. HL-60 leukaemia cells were treated with methanol extracts of different Scrophularia species leading to strong growth inhibition and high cell death rates.
View Article and Find Full Text PDFBackground: The intravasation of breast cancer into the lymphendothelium is an early step of metastasis. Little is known about the mechanisms of bulky cancer invasion into lymph ducts.
Methods: To particularly address this issue, we developed a 3-dimensional co-culture model involving MCF-7 breast cancer cell spheroids and telomerase-immortalised human lymphendothelial cell (LEC) monolayers, which resembles intravasation in vivo and correlated the malignant phenotype with specific protein expression of LECs.
Natural products continue to represent the main source for therapeutics, and ethnopharmacological remedies from high biodiversity regions are a rich source for the development of novel drugs. Hence, in our attempt to find new anti-neoplastic activities we focused on ethno-medicinal plants of the Maya, who live in the world's third richest area in vascular plant species. Pluchea odorata (Asteraceae) is traditionally used for the treatment of various inflammatory disorders and recently, the in vitro anti-cancer activities of different extracts of this plant were described.
View Article and Find Full Text PDFResveratrol is a naturally occurring anticancer compound present in grapes and wine with antiproliferative properties against breast cancer cells and xenografts. Our objective was to investigate the metabolic alterations that characterize the effects of resveratrol in the human breast cancer cell lines MCF-7 and MDA-MB-231 using high-throughput liquid chromatography-based mass spectrometry. In both cell lines, growth inhibition was dose dependent and accompanied by substantial metabolic changes.
View Article and Find Full Text PDFThere is increasing evidence of the direct antiproliferative effects of various steroidal structures, including cardenolides, steroidal alkaloids and sexual hormones. The aim of the present study was to characterize the antiproliferative effects of three synthetic solanidine analogs (1-3) on HL-60 human leukemia cells. The three compounds exerted similar cytostatic effects (IC(50) values: 1.
View Article and Find Full Text PDFRibonucleotide reductase (RR; EC 1.17.4.
View Article and Find Full Text PDFBackground: Digalloyl-resveratrol (di-GA) is a synthetic compound aimed to combine the biological effects of the plant polyhydroxy phenols gallic acid and resveratrol, which are both radical scavengers and cyclooxygenase inhibitors exhibiting anticancer activity. Their broad spectrum of activities may probably be due to adjacent free hydroxyl groups.
Methods: Protein activation and expression were analysed by western blotting, deoxyribonucleoside triphosphate levels by HPLC, ribonucleotide reductase activity by (14)C-cytidine incorporation into nascent DNA and cell-cycle distribution by FACS.
Berberis lycium Royle (Berberidacea) from Pakistan and its alkaloids berberine and palmatine have been reported to possess beneficial pharmacological properties. In the present study, the anti-neoplastic activities of different B. lycium root extracts and the major constituting alkaloids, berberine and palmatine were investigated in p53-deficient HL-60 cells.
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