Background: The chemokine receptor CXCR4 and the transcription factor JUNB, expressed on a variety of tumor cells, seem to play an important role in the metastatic process. Since disseminated tumor cells (DTCs) in the bone marrow (BM) have been associated with worse outcomes, we evaluated the expression of CXCR4 and JUNB in DTCs of primary, nonmetastatic breast cancer (BC) patients before the onset of any systemic treatment.
Methods: Bilateral BM (10 ml) aspirations of 39 hormone receptor (HR)-positive, HER2-negative BC patients were assessed for the presence of DTCs using the following combination of antibodies: pan-cytokeratin (A45-B/B3)/CXCR4/JUNB.
Recent studies revealed that the histone demethylase KDM2B regulates the epithelial markers E-Cadherin and ZO-1, the RhoA/B/C-small-GTPases and actin cytoskeleton organization, in DU-145 prostate- and HCT-116 colon-tumor cells. Here we addressed the role of KDM2B in the activation of Focal Adhesion Kinase (FAK)-signaling and its involvement in regulating tumor cell motility. We used RT-PCR for gene transcriptional analysis, Western blotting for the assessment of protein expression and activity and wound-healing assay for the study of cell migration.
View Article and Find Full Text PDFBackground: Circulating tumor cells (CTCs) are important for metastatic dissemination of cancer. They can provide useful information, regarding biological features and tumor heterogeneity; however, their detection and characterization are difficult due to their limited number in the bloodstream and their mesenchymal characteristics. Therefore, new biomarkers are needed to address these questions.
View Article and Find Full Text PDFExpression of the serum- and glucocorticoid-inducible kinase 1 (SGK1) is up-regulated by several types of cell stress, such as ischemia, radiation and hyperosmotic shock. The SGK1 protein is activated by a signaling cascade involving phosphatidylinositide-3-kinase (PI3K), 3-phosphoinositide-dependent kinase 1 (PDK1) and mammalian target of rapamycin (mTOR). SGK1 up-regulates Na/K-ATPase, a variety of carriers including Na-,K-,2Cl- cotransporter (NKCC), NaCl cotransporter (NCC), Na/H exchangers, diverse amino acid transporters and several glucose carriers such as Na-coupled glucose transporter SGLT1.
View Article and Find Full Text PDFPlacental growth factor (PlGF) is produced by tumor cells and stimulates tumor growth and metastasis in part by upregulation of hypoxia inducible factor HIF1α. Orchestration of tumor cell proliferation and migration involves oscillations of cytosolic Ca activity ([Ca]). The [Ca] oscillations could be accomplished by triggering of intracellular Ca release followed by store-operated Ca-entry (SOCE).
View Article and Find Full Text PDFBackground/aims: The epigenetic factor KDM2B is a histone demethylase expressed in various tumors. Recently, we have shown that KDM2B regulates actin cytoskeleton organization, small Rho GTPases signaling, cell-cell adhesion and migration of prostate tumor cells. In the present study, we addressed its role in regulating EMT and small GTPases expression in colon tumor cells.
View Article and Find Full Text PDFBackground/aims: Istaroxime is a validated inotropic Na+/K+ ATPase inhibitor currently in development for the treatment of various cardiac conditions. Recent findings established that this steroidal drug exhibits potent apoptotic responses in prostate tumors in vitro and in vivo, by affecting key signaling orchestrating proliferation and apoptosis, such as c-Myc and caspase 3, Rho GTPases and actin cytoskeleton dynamics. In the present study we examined whether istaroxime is affecting cell motility and analyzed the underlying mechanism in prostate tumor cells.
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