Osteopontin Deficiency in Rat Vascular Smooth Muscle Cells is Associated with an Inability to Adhere to Collagen and Increased Apoptosis

Weintraub, Andrea S.; Schnapp, Lynn M.; Lin, Xinjie; Taubman, Mark B.

doi:10.1038/labinvest.3780171

Cited by 38 publications

(31 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Additionally, osteopontin-deficient vascular smooth muscle cells show increased apoptosis and decreased adherence. This not only provides further evidence for the role of osteopontin in cellular adherence but also in the inhibition of apoptosis (Weintraub et al, 2000). The mechanism by which osteopontin inhibits apoptosis is thought to be via multiple ligand receptor interactions in response to various proapoptotic signals (Denhardt et al, 2001).…”

Section: Discussionmentioning

confidence: 72%

Osteopontin expression correlates with adhesive and metastatic potential in metastasis-inducing DNA-transfected rat mammary cell lines

Moye¹,

Barraclough²,

West

et al. 2004

Br J Cancer

View full text Add to dashboard Cite

A metastatic phenotype can be induced in benign rat mammary cells (Rama 37 cells) by transfecting them with metastasis-inducing DNAs (Met-DNAs). Stable transfection of Met-DNAs increases the level of the metastasis-associated protein, osteopontin. Randomly picked clonal cell lines have been established from the pool of Rama 37 cells transfected with one metastasis-inducing DNA, C9-Met-DNA. In these cell lines, moderate correlation is observed between the copy number of C9-Met-DNA and their metastatic potential (linear regression coefficient, R 2 ¼ 0.48). A very close correlation is observed between the cell lines' metastatic potential in vivo and the osteopontin mRNA levels in vitro (R 2 ¼ 0.74), but not with another metastasis-associated protein in this system, S100A4 (R 2 ¼ 0.21). A close correlation is also observed between osteopontin mRNA levels and the adhesive potential (R 2 ¼ 0.91) of the cells, but not with their growth rate in vitro (R 2 ¼ 0.03). These observations support the previous suggestion that osteopontin is the direct effector of C9-Met-DNA and that the presence of C9-Met-DNA is necessary, if not sufficient, for the induction of metastasis in vivo in this system. Additionally, these results suggest that Rama 37 cells with increased osteopontin mRNA levels become metastatic not through an increased growth rate, but through an increase in cellular adhesiveness.

show abstract

Section: Discussionmentioning

confidence: 72%

Osteopontin expression correlates with adhesive and metastatic potential in metastasis-inducing DNA-transfected rat mammary cell lines

Moye¹,

Barraclough²,

West

et al. 2004

Br J Cancer

View full text Add to dashboard Cite

show abstract

“…Integrin-mediated signaling has been linked to a number of factors directly governing cell resistance to apoptosis, including cell cycle progression 10 and p53 activation, 35 Bcl-2 family protein expression, 34 death receptor and death ligand expression 41,42 and regulation of the PI3K/Akt/ GSKb axis. 43 Moreover, these signaling events also influence cellular production of extracellular proteins, such as osteopontin 44 and intracellular adaptors, such as osteoprotegerin 45 and c-flip, 42 which themselves act directly or indirectly to regulate cell survival.…”

Section: General Signaling Events Initiated By Integrinsmentioning

confidence: 99%

Integrins as a distinct subtype of dependence receptors

Stupack

2005

Cell Death Differ

View full text Add to dashboard Cite

In the absence of their cognate ligand, dependence receptors trigger programmed cell death. This function is the defining feature of dependence receptors, which include members of several different protein families. The integrins are a family of heterodimeric receptors for extracellular matrix (ECM) proteins, mediating cell anchorage and migration. Integrins share characteristics with dependence receptors, and integrin binding to substrate ECM ligands is essential for cell survival. Although integrins do not conform in all characteristics to the established definitions of dependence receptors, alterations in the expression of integrins and their ligands during physiological and pathological events, such as wound healing, angiogenesis and tumorigenesis, do regulate cell fate in a ligand-dependent manner. This biosensory function of integrins fits well with our current concept of dependence receptor action, and thus integrins may rightly be considered to comprise a distinct subclass of dependence receptor.

show abstract

“…In addition to anti-apoptotic function as described, OPN improves survival of interstitial and tubular cells (Ophascharoensuk et al, 1999), endothelial cells (Khan et al, 2002), and vascular smooth muscle cells (Weintraub et al, 2000). The deficiency of OPN influenced neuronal loss in KO mice and impaired locomotor recovery after spinal cord injury.…”

Section: Locomotor Recovery and Histologymentioning

confidence: 99%

Osteopontin-Deficient Mice Exhibit Less Inflammation, Greater Tissue Damage, and Impaired Locomotor Recovery from Spinal Cord Injury Compared with Wild-Type Controls

Hashimoto¹,

Sun

Rittling

et al. 2007

J. Neurosci.

View full text Add to dashboard Cite

Osteopontin (OPN) is expressed in many tissues during inflammatory responses. After spinal cord injury, microglia expresses OPN at the site of injury during the early to subacute stages. However, the function of OPN in spinal cord injury is not well understood. This study examines the responses of OPN knock-out (KO) and wild-type (WT) mice to spinal cord contusion injury. KO and WT mice were injured with a modified New York University impactor. Weights of 10 or 5.6 g were dropped 6.25 mm onto the T13 spinal cord under isoflurane anesthesia. At 24 h, homogenized spinal cords were analyzed for total potassium concentration to estimate lesion volumes. Expression of apoptotic genes, proinflammatory cytokines, and nerve growth factors was measured by reverse transcription (RT)-PCR and Western blot. In a series of animals, locomotor recovery was assessed with the Basso mouse scale (BMS) for 6 weeks, and histological analyses was performed to determine tissue preservation. Lesion volume showed no significant differences between KO and WT mice at 24 h. RT-PCR indicated that KO mice had significantly less Bcl-2, tumor necrosis factor-␣, interleukin-1␤, and interleukin-6 mRNA compared with WT controls. Western blot also showed that KO had significantly less Bcl-2 7 d after spinal cord injury. KO mice had significantly worse BMS locomotor scores than WT at 6 weeks. KO mice also had a significantly reduced area of spared white matter and fewer neuronal-specific nuclear protein-positive neurons in the spinal cord surrounding the impact site. This result supports a potential neuroprotective role for OPN in the inflammatory response to spinal cord injury.

show abstract

Osteopontin Deficiency in Rat Vascular Smooth Muscle Cells is Associated with an Inability to Adhere to Collagen and Increased Apoptosis

Cited by 38 publications

References 53 publications

Osteopontin expression correlates with adhesive and metastatic potential in metastasis-inducing DNA-transfected rat mammary cell lines

Osteopontin expression correlates with adhesive and metastatic potential in metastasis-inducing DNA-transfected rat mammary cell lines

Integrins as a distinct subtype of dependence receptors

Osteopontin-Deficient Mice Exhibit Less Inflammation, Greater Tissue Damage, and Impaired Locomotor Recovery from Spinal Cord Injury Compared with Wild-Type Controls

Contact Info

Product

Resources

About