Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have recently characterized a human bladder cancer cell line T24 and a more aggressive lineage related variant of it, T24T. To gain further insights, we have studied their metastatic ability in an in vivo model system. Results show that T24 forms significantly fewer [4/12 (1/11) mice had metastases with 1-2 lesions/mouse] metastasis in SCID/bg mice than T24T [14/14 (6/6) mice had metastases with a mean of 24-28 lesions/mouse]. To begin exploring the mechanisms underlying this difference, we evaluated the mRNA and protein expression levels of metastasis-suppressor genes, known to be important in the progression of other cancers, in our model of bladder cancer progression. A higher mRNA expression of BRMS1, a metastasis suppressor in breast cancer, was observed in T24 cells. In addition, RhoGDI2 mRNA expression was only observed in T24 when compared to T24T, suggesting that Rho activation might play a significant role in the metastatic cascade. However, a basal level mRNA expression of KISS1, described as metastasis suppressor in melanoma and breast, was observed in both the lines and had slightly higher expression in T24T. No difference of Nm23-H1, KAI1, MKK4/SEK1 and E-Cadherin protein levels were noted between these two lines. In summary, it appears that the T24/T24T paired cell lines constitute a useful model for the study of human bladder cancer metastasis that will allow both the discovery and mechanistic evaluation of genes potentially involved in this process.
Clin Exp Metastasis 2000
PMID:The relationship of BRMS1 and RhoGDI2 gene expression to metastatic potential in lineage related human bladder cancer cell lines. 1159 9

Half of patients treated for locally advanced bladder cancer relapse with often fatal metastatic disease to the lung. We have recently shown that reduced expression of the GDP dissociation inhibitor, RhoGDI2, is associated with decreased survival of patients with advanced bladder cancer. However, the effectors by which RhoGDI2 affects metastasis are unknown. Here we use DNA microarrays to identify genes suppressed by RhoGDI2 reconstitution in lung metastatic bladder cancer cell lines. We identify such RNAs and focus only on those that also increase with tumor stage in human bladder cancer samples to discover only clinically relevant targets of RhoGDI2. Levels of endothelin-1 (ET-1), a potent vasoconstrictor, were affected by both RhoGDI2 reconstitution and tumor stage. To test the hypothesis that the endothelin axis is important in lung metastasis, lung metastatic bladder carcinoma cells were injected in mice treated with the endothelin receptor-specific antagonist, atrasentan, thereby blocking engagement of the up-regulated ET-1 ligand with its cognate receptor. Endothelin antagonism resulted in a dramatic reduction of lung metastases, similar to the effect of reexpressing RhoGDI2 in these metastatic cells. Taken together, these experiments show a novel approach of identifying therapeutic targets downstream of metastasis suppressor genes. The data also suggest that blockade of the ET-1 axis may prevent lung metastasis, a new therapeutic concept that warrants clinical evaluation.
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PMID:Endothelin axis is a target of the lung metastasis suppressor gene RhoGDI2. 1610 83

Rho guanine nucleotide dissociation inhibitors (RhoGDIs) regulate the activity of Rho family GTPases. RhoGDIbeta (LyGDI/GDID4/RhoGDI2) has two caspase cleavage sites after Asp19 and Asp55. The resulting cleavage products, DeltaN(1-19)RhoGDIbeta and DeltaN(1-55)RhoGDIbeta, are expressed in cells under conditions that activate caspases. DeltaN(1-19)RhoGDIbeta, which can inhibit GDP dissociation, is implicated in the process of apoptosis, whereas the physiological roles for DeltaN(1-55)RhoGDIbeta, which lacks the ability to inhibit GDP dissociation, are largely unknown. To explore the roles of DeltaN(1-55)RhoGDIbeta, we examined the phenotypes of v-src-transformed metastatic fibroblasts transfected with plasmids for expressing DeltaN(1-55)RhoGDIbeta. Although the expression of DeltaN(1-55)RhoGDIbeta had no effect on the rate of growth in vitro, it suppressed experimental metastasis and decreased the rate of growth in vivo. In addition, DeltaN(1-55)RhoGDIbeta-expressing cells had enhanced adhesion to fibronectin, laminin, and collagens but reduced retention in the lung after intravenous injection. Also, the expression of DeltaN(1-55)RhoGDIbeta promoted anoikis without affecting the levels of activated Rac1 or Cdc42. Furthermore, DeltaN(1-55)RhoGDIbeta did not affect the expression or phosphorylation of focal adhesion kinase, p44/p42 mitogen-activated protein kinases, or Akt1 before or after induction of anoikis. Thus, DeltaN(1-55)RhoGDIbeta appears to promote anoikis by undefined mechanisms, thereby suppressing metastasis in v-src-transformed fibroblasts.
Clin Exp Metastasis 2006
PMID:RhoGDIbeta lacking the N-terminal regulatory domain suppresses metastasis by promoting anoikis in v-src-transformed cells. 1711 Dec 35

Half of patients with muscle-invasive bladder cancer develop metastatic disease, and this is responsible for most of the deaths from this cancer. Low expression of RhoGTP dissociation inhibitor 2 (RhoGDI2; also known as ARHGDIB and Ly-GDI) is associated with metastatic disease in patients with muscle-invasive bladder cancer. Moreover, a reduction in metastasis is observed upon reexpression of RhoGDI2 in xenograft models of metastatic cancer. Here, we show that RhoGDI2 suppresses lung metastasis in mouse models by reducing the expression of isoforms V1 and V3 of the proteoglycan versican (VCAN; also known as chondroitin sulfate proteoglycan 2 [CSPG2]). In addition, we found that high versican levels portended poor prognosis in patients with bladder cancer. The functional importance of tumor expression of versican in promoting metastasis was established in in vitro and in vivo studies in mice that implicated a role for the chemokine CCL2 (also known as MCP1) and macrophages. Further analysis indicated that RhoGDI2 suppressed metastasis by altering inflammation in the tumor microenvironment. In summary, we demonstrate what we believe to be a new mechanism of metastasis suppression that works by reducing host responses that promote metastatic colonization of the lung. Therapeutic targeting of these interactions may provide a novel adjuvant strategy for delaying the appearance of clinical metastasis in patients.
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PMID:RhoGDI2 suppresses lung metastasis in mice by reducing tumor versican expression and macrophage infiltration. 2250 58

RhoGDI2 is a guanine nucleotide dissociation inhibitor (GDI) specific for the Rho family of small GTPases that plays dual opposite roles in tumor progression, being both a promoter in tissues such as breast and a metastasis suppressor in tissues such as the bladder. Despite a clear role for this protein in modulating the invasive and metastatic process, the mechanisms through which RhoGDI2 executes these functions remain unclear. This review will highlight the current state of our knowledge regarding how RhoGDI2 functions in metastasis with a focus on bladder cancer and will also seek to highlight other potential underappreciated avenues through which this protein may affect cancer cell behavior.
Cancer Metastasis Rev 2012 Dec
PMID:The faces and friends of RhoGDI2. 2271 98

Intratumoral hypoxia occurs in many solid tumors, where it is associated with the development of metastatic character. However, the connections between these phenomena are not fully understood. In this study, we define an integrative role for the E3 ubiquitin ligase subunit WSB1. In primary osteosarcomas, increased levels of WSB1 correlated with pulmonary metastatic potential. RNAi-mediated attenuation of WSB1 or disruption of its E3 ligase activity potently suppressed tumor metastasis. Quantitative proteomic and functional analyses revealed that WSB1 ubiquitylates the Rho-binding protein RhoGDI2 and promotes its proteasomal degradation, thereby activating Rac1 to stimulate tumor cell motility and invasion. Our findings show how WSB1 regulates key steps of the metastatic cascade in hypoxia-driven osteosarcoma, and they highlight a candidate therapeutic target to potentially improve the survival of patients with metastatic disease.
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PMID:Hypoxia-Induced WSB1 Promotes the Metastatic Potential of Osteosarcoma Cells. 3248 89

Cutaneous squamous cell carcinomas (cSCCs) are common human carcinomas. Despite having metastasizing capacities, they usually show less aggressive progression compared to squamous cell carcinoma (SCC) of other organs. Metastasis suppressor proteins (MSPs) are a group of proteins that control and slow-down the metastatic process. In this study, we established the importance of seven well-defined MSPs including NDRG1, NM23-H1, RhoGDI2, E-cadherin, CD82/KAI1, MKK4, and AKAP12 in cSCCs. Protein expression levels of the selected MSPs were detected in 32 cSCCs, 6 in situ SCCs, and two skin cell lines (HaCaT, A-431) by immunohistochemistry. The results were evaluated semi-quantitatively using the HSCORE system. In addition, mRNA expression levels were detected by qRT-PCR in the cell lines. The HSCOREs of NM23-H1 were similar in cSCCs and normal skin tissues, while RGHOGDI2, E-cadherin and AKAP12 were significantly downregulated in cSCCs compared to normal skin. The levels of MKK4, NDRG1 and CD82 were partially conserved in cSCCs. In stage I SCCs, nuclear staining of NM23-H1 (NM23-H1nuc) was significantly lower than in stage II/III SCCs. Only nuclear staining of MKK4 (MKK4nuc) showed significantly higher scores in in situ carcinomas compared to invasive SCCs. In conclusion, similar to other human tumors, we have demonstrated complex differential expression patterns for the MSPs in in-situ and invasive cSCCs. This complex MSP signature warrants further biological and experimental pathway research.
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PMID:Metastasis suppressor proteins in cutaneous squamous cell carcinoma. 2721 90

Unconventional myosin VIIA (Myo7a) is an actin-based motor molecule that normally functions in the cochlear hair cells of the inner ear. Mutations of MYO7A/Myo7a have been implicated in inherited deafness in both humans and mice. However, there is limited information about the functions of Myo7a outside of the specialized cells of the ears. Herein, we report a previously unidentified function of Myo7a by demonstrating that it plays an important role in melanoma progression. We found that silencing Myo7a by means of RNAi inhibited melanoma cell growth through upregulation of cell cycle regulator p21 (also known as CDKN1A) and suppressed melanoma cell migration and invasion through downregulation of RhoGDI2 (also known as ARHGDIB) and MMP9. Furthermore, Myo7a depletion suppressed melanoma cell metastases to the lung, kidney and bone in mice. In contrast, overexpression of Myo7a promoted melanoma xenograft growth and lung metastasis. Importantly, Myo7a levels are remarkably elevated in human melanoma patients. Collectively, we demonstrated for the first time that Myo7a is able to function in non-specialized cells, a finding that reveals the complicated disease-related roles of Myo7a, especially in melanomas.
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PMID:Unconventional myosin VIIA promotes melanoma progression. 2936 40