background : the development of chemoresistance represents a major obstacle in the successful treatment of cancers such as non-hodgkin’s lymphoma (nhl). with the recognition of important roles for both p53 and its more recently described paralog p73 in mediating the activity of anti-cancer drugs, there has been increasing recognition that cellular resistance to anthracyclines could and does a...

The tight junction protein ZO-1 inhibits G1/S-phase transition by cytoplasmic sequestration of a complex formed by CDK4 and the transcription factor ZONAB. Canine ZONAB is the homologue of human DbpA, an E2F target gene that is overexpressed in different carcinomas. Since the ZONAB target genes that are involved in G1/S-phase transition are unknown, we employed the mammary epithelial cell line ...

Disruption of cellular plasma membranes is a common event in many animal tissues, and the membranes are usually rapidly resealed. Moreover, repeated membrane disruptions within a single cell reseal faster than the initial wound in a protein kinase A (PKA)- and protein kinase C (PKC)-dependent manner. In addition to wounded cells, recent studies have demonstrated that wounding of Madin-Darby can...

Epidermal growth factor receptor (EGFR) function is transregulated by a variety of stimuli, including agonists of certain G-protein-coupled receptors (GPCRs). One of the most ubiquitous GPCRs is the P2Y(1) receptor (P2RY1, hereafter referred to as P2Y(1)R) for extracellular nucleotides, mainly ADP. Here, we show in tumoral HeLa cells and normal FRT epithelial cells that P2Y(1)R broadcasts mitog...

Four water-soluble Fusarium metabolites (fumonisin B1, fusaric acid, butenolide and moniliformin), water-insoluble pigment (8-O-methylbostrycoidin), and an Alternaria metabolite (AAL-toxin) were tested for relative cytotoxicity to five established mammalian cell lines. Butenolide was the most cytotoxic to all five cell lines. LC50s were; 1 microgram/ml to rat hepatoma (RH) (tumors derived from ...

The interaction between late endocytic structures and microtubules in polarized cells was studied using a procedure previously shown to cause microtubule-dependent redistribution of lysosomes in fibroblasts and macrophages (Heuser, J. 1989. J. Cell Biol. 108:855-864). In cultured rat hippocampal neurons, low cytoplasmic pH caused cation-independent mannose-6-phosphate receptor-enriched structur...

Epithelial-mesenchymal transition (EMT) describes a morphogenetic program which confers mesenchymal cell properties, such as reduced cell-cell contact and increased cell migration and invasion, to epithelial cells. Here we investigate the role of the pleiotropic transcription/splicing factor and RNA-binding protein nuclease-sensitive element-binding protein 1 (YBX1/YB-1) in increasing the oncog...

P-glycoprotein (P-gp) is one of the best-known ATP-dependent efflux transporters, contributing to differences in pharmacokinetics and drug-drug interactions. Until now, studies on pig P-gp have been scarce. In our studies, the full-length porcine P-gp cDNA was cloned and expressed in a Madin-Darby Canine Kidney (MDCK) cell line. P-gp expression was then determined in tissues and its role in the...

To assess the participation of the 150-kDa oxygen-regulated protein (ORP150) in protein transport, its function in Madin-Darby canine kidney (MDCK) cells was studied. Exposure of MDCK cells to hypoxia resulted in an increase of ORP150 antigen and increased binding of ORP150 to GP80/clusterin (80-kDa glycoprotein), a natural secretory protein in this cell line. In ORP150 antisense transformant M...