Carbohydrate-binding protein 35 is the major cell-surface laminin-binding protein in colon carcinoma
UMass Chan AffiliationsDepartment of Cancer Biology
Tumor Cells, Cultured
Amino Acids, Peptides, and Proteins
Digestive System Diseases
MetadataShow full item record
AbstractThe interaction of tumor cells with laminin is thought to be critical in invasion and metastasis. We found that an endogenous lectin, carbohydrate-binding protein 35 (CBP-35), is the major laminin-binding protein on human colon carcinoma cells and that its surface expression suggests involvement in metastasis. We identified CBP-35 by laminin-affinity chromatography and immunoblotting. Surface expression of CBP-35 on eight human colon carcinoma cell lines was compared by flow cytometry. Poorly differentiated cell lines and DLD-2, a signet-ring carcinoma cell line, expressed more surface CBP-35 than well-differentiated cell lines. Poorly differentiated cell lines and DLD-2 are characterized as aggressive cell lines because they adhere to and invade through reconstituted basement membrane significantly better than well-differentiated cell lines. These data suggest that CBP-35 is involved in tumor cell-basement membrane interactions and that an increase in CBP-35 surface expression may facilitate metastatic potential of colon carcinoma cells.
Arch Surg. 1991 Dec;126(12):1498-502.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/26210
Showing items related by title, author, creator and subject.
Dynamic Regulation at the Neuronal Plasma Membrane: Novel Endocytic Mechanisms Control Anesthetic-Activated Potassium Channels and Amphetamine-Sensitive Dopamine Transporters: A DissertationHaley Melikian, PhD; Gabriel, Luke R. (2013-06-13)Endocytic trafficking dynamically regulates neuronal plasma membrane protein presentation and activity, and plays a central role in excitability and plasticity. Over the course of my dissertation research I investigated endocytic mechanisms regulating two neuronal membrane proteins: the anesthetic-activated potassium leak channel, KCNK3, as well as the psychostimulant-sensitive dopamine transporter (DAT). My results indicate that KCNK3 internalizes in response to Protein Kinase C (PKC) activation, using a novel pathway that requires the phosphoserine binding protein, 14-3-3β, and demonstrates for the first time regulated KCNK3 channel trafficking in neurons. Additionally, PKC-mediated KCNK3 trafficking requires a non-canonical endocytic motif, which is shared exclusively between KCNK3 and sodium-dependent neurotransmitter transporters, such as DAT. DAT trafficking studies in intact ex vivo adult striatal slices indicate that DAT endocytic trafficking has both dynamin-dependent and –independent components. Moreover, DAT segregates into two populations at the neuronal plasma membrane: trafficking-competent and -incompetent. Taken together, these results demonstrate that novel, non-classical endocytic mechanisms dynamically control the plasma membrane presentation of these two important neuronal proteins.
Selective interaction of JNK protein kinase isoforms with transcription factorsGupta, Shashi; Barrett, Tamera; Whitmarsh, Alan J.; Cavanagh, Julie; Sluss, Hayla Karen; Derijard, Benoit; Davis, Roger J. (1996-06-03)The JNK protein kinase is a member of the MAP kinase group that is activated in response to dual phosphorylation on threonine and tyrosine. Ten JNK isoforms were identified in human brain by molecular cloning. These protein kinases correspond to alternatively spliced isoforms derived from the JNK1, JNK2 and JNK3 genes. The protein kinase activity of these JNK isoforms was measured using the transcription factors ATF2, Elk-1 and members of the Jun family as substrates. Treatment of cells with interleukin-1 (IL-1) caused activation of the JNK isoforms. This activation was blocked by expression of the MAP kinase phosphatase MKP-1. Comparison of the binding activity of the JNK isoforms demonstrated that the JNK proteins differ in their interaction with ATF2, Elk-1 and Jun transcription factors. Individual members of the JNK group may therefore selectively target specific transcription factors in vivo.
Role of the Raf/mitogen-activated protein kinase pathway in p21ras desensitizationKlarlund, Jes K.; Cherniack, Andrew D.; McMahon, Martin; Czech, Michael P. (1996-07-12)Desensitization of p21(ras) after stimulation of cells by growth factors and phorbol 12-myristate 13-acetate (PMA) correlates with hyperphosphorylation of the guanine nucleotide exchange factor Son-of-sevenless (Sos) and its dissociation from the adaptor protein Grb2 (Cherniack, A., Klarlund, J. K., Conway, B. R., and Czech, M. P. (1995) J. Biol. Chem. 270, 1485-1488). To test the role of the Raf/mitogen-activated protein (MAP) kinase pathway, we utilized cells expressing a chimera composed of the catalytic domain of p74Raf-1 and the hormone binding domain of the estradiol receptor (DeltaRaf-1:ER). Estradiol markedly stimulated DeltaRaf-1:ER and the downstream MEK and MAP kinases in these cells as well as Sos phosphorylation. However, the dissociation of Grb2 from Sos observed in response to PMA was not apparent upon DeltaRaf-1:ER activation. Furthermore, stimulation of DeltaRaf-1:ER did not impair GTP loading of p21(ras) in response to platelet-derived growth factor or epidermal growth factor. We conclude that activation of the Raf/MAP kinase pathway alone in these cells is insufficient to cause disassembly of Sos from Grb2 or to interrupt the ability of Sos to catalyze activation of p21(ras).