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)

The Epstein-Barr virus LMP2A protein was expressed in a human keratinocyte cell line, HaCaT, and effects on epithelial cell growth were detected in organotypic raft cultures and in vivo in nude mice. Raft cultures derived from LMP2A-expressing cells were hyperproliferative, and epithelial differentiation was inhibited. The LMP2A-expressing HaCaT cells were able to grow anchorage independently and formed colonies in soft agar. HaCaT cells expressing LMP2A were highly tumorigenic and formed aggressive tumors in nude mice. The LMP2A tumors were poorly differentiated and highly proliferative, in contrast to occasional tumors that arose from parental HaCaT cells and vector control cells, which grew slowly and remained highly differentiated. Animals injected with LMP2A-expressing cells developed frequent metastases, which predominantly involved lymphoid organs. Involucrin, a marker of epithelial differentiation, and E-cadherin, involved in the maintenance of intercellular contact, were downregulated in LMP2A tumors. Whereas activation of the mitogen-activated protein kinase pathway was not observed, phosphatidylinositol-3-kinase (PI3-kinase)-dependent activation of the serine-threonine kinase Akt was detected in LMP2A-expressing cells and LMP2A tumors. Inhibition of this pathway blocked growth in soft agar. These data indicate that LMP2A greatly affects cell growth and differentiation pathways in epithelial cells, in part through activation of the PI3-kinase-Akt pathway.
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PMID:Epstein-Barr virus LMP2A transforms epithelial cells, inhibits cell differentiation, and activates Akt. 1104 12

Carcinoma cell lines are frequently refractory to transforming growth factor-beta (TGF beta)-mediated cell cycle arrest. Whether and how TGF beta signaling is disrupted in the majority of human tumors, however, remains unclear. To investigate whether TGF beta signaling might be disrupted by inactivation of the key signaling molecule, the TGF beta type I (T beta R-I) receptor, and whether or not T beta R-I inactivation is associated with late stage disease, we conducted a comprehensive structural analysis of the T beta R-I gene in fine-needle aspirates of 23 head-&-neck cancer metastases. We encountered 4 different mutations of T beta R-I, 3 of which have not been previously identified. In 1 case, we found a somatic intragenic 4-bp deletion predicting for a truncation of the receptor protein. This is the first example of a true loss-of-function mutation of T beta R-I in a human epithelial neoplasm. In 2 other cases, we identified missense mutations located between the juxtamembrane- and serine-threonine kinase domains. One of these resulted in an alanine-to-threonine substitution (A230T), which disrupts receptor signaling activity by causing rapid protein degradation within the endoplasmatic reticulum. This represents a novel mechanism of inactivation of a TGF beta signaling intermediate. Finally, we identified a serine-to-tyrosine substitution at codon 387 (S387Y) in a metastasis but not in the corresponding primary tumor. We had previously shown this S387Y mutant to be predominantly associated with breast cancer metastases and to have a diminished ability to mediate TGF beta-dependent signaling. In aggregate, these findings provide further support for the hypothesis that inactivation of the TGF beta signaling pathway occurs in a significant subset of human cancers.
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PMID:Novel inactivating mutations of transforming growth factor-beta type I receptor gene in head-and-neck cancer metastases. 1147 74

Aurora kinases representing a novel family of serine/threonine kinases have been identified as key regulators of the mitotic cell division process. The three members of this kinase family, identified so far, referred to as Aurora-A, Aurora-B and Aurora-C kinases, are close homologues of the prototypic yeast Ipll and Drosophila aurora kinases, which are known to be involved in the regulation of centrosome function, bipolar spindle assembly and chromosome segregation processes. All three members of the mammalian kinase family have a catalytic domain that is highly conserved with a short C-terminal domain and an N-terminal domain of varying sizes. Following their discovery about five years ago, extensive research has focused on understanding the biological roles of these kinases and elucidation of their pathways, which regulate cell proliferation and maintenance of normal cellular phenotypes. Significant interest in the subject was generated since all three Aurora kinases family members were reported to be overexpressed in many human cancers, and elevated expression has been correlated with chromosomal instability and clinically aggressive disease in some instances. Ectopic overexpression of one member of the family, Aurora-A, was shown to induce oncogenic transformation in cells. Unlike most other putative oncogenes identified, so far, members of this kinase family are expressed and active at the highest level during G2-M phase of the cell cycle. Aurora kinases are localized at the centrosomes of interphase cells, at the poles of the bipolar spindle and in the midbody of the mitotic apparatus. Substrates identified for the Aurora-A and Aurora-B kinases, include a kinesin-like motor protein, spindle apparatus proteins, histone H3 protein, kinetochore protein and the tumor suppressor protein p53. Identification of Aurora kinases as RasGAP Src homology 3 domain binding protein, also implicates these kinases as potential effectors in the Ras pathway relevant to oncogenesis. Abnormal elevated expression of Aurora kinases detected in human cancer cells could help explain the underlying biological mechanisms responsible for the development of many cellular phenotypes associated with malignant cells. Identification of these mechanisms offers the possibility of designing novel targeted therapies for cancer in the future.
Cancer Metastasis Rev 2003 Dec
PMID:The Aurora kinases: role in cell transformation and tumorigenesis. 1288 18

STK15/BTAK/Aurora-A involved in regulating centrosomes and chromosome segregation is amplified and overexpressed in human cancers. A T91A polymorphism in STK15 causes Phe31Ile substitution, and the 31Ile variant has been shown to be preferentially amplified and associated with degree of aneuploidy in human tumors. We genotyped 656 patients with esophageal squamous cell carcinoma (ESCC) and 656 controls for the polymorphism to examine the hypothesis that the STK15 variation may affect individual susceptibility to the occurrence and aggression of ESCC. It was found that the Ile/Ile genotype was significantly associated with increased risk of ESCC occurrence [odds ratio (OR) = 1.97, 95% confidence interval (CI) = 1.36-2.85] compared with the Phe/Phe genotype. The 31Ile allele frequency significantly increased as ESCC stage increased (trend test, P = 0.006). Patients with the Ile/Ile genotype had an increased risk for invasive disease (stage II-IV; OR = 2.13, 95% CI = 1.04-4.39) or metastatic disease (stage III and IV; OR = 2.31, 95% CI = 1.06-5.05) compared with those with the Phe/Phe genotype. A positive correlation between the Ile/Ile genotype and high ESCC grade was also observed. Our results demonstrate for the first time that the STK15 polymorphism is a genetic susceptibility factor for the occurrence and aggression of ESCC.
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PMID:Functional STK15 Phe31Ile polymorphism is associated with the occurrence and advanced disease status of esophageal squamous cell carcinoma. 1508 79

The aggressive behavior of breast cancer cells can at times be modulated by hormonal mechanisms. Exposure to glucocorticoids (GC) has been shown to stimulate the invasiveness, motility and adhesiveness of breast cancer cells containing the glucocorticoid receptor. This is largely explained by GC-associated overexpression of the c-fms proto-oncogene, which encodes the receptor for the colony stimulating factor-1 (CSF-1). Our objective is to investigate additional GC-associated genetic alterations that could modulate c-fms related malignant behavior in breast cancer cells. A microarray technique using an oligonucleotide array representing 16,700 known expressed human genes was used to analyze the gene expression profile of breast cancer cells exposed to dexamethasone (Dex) or vehicle. Results were confirmed by western blot analysis. Six genes were found to be consistently differentially overexpressed in the Dex-exposed cells compared to control. We focused on serum-glucose kinase 1 (SGK1), a serine-threonine kinase known to be involved in intracellular signal transduction pathways and induced by GC and serum. An adhesion assay was performed on extracellular matrix after exposing the breast cancer cells to Dex, CSF-1 or to Dex or CSF-1 plus LY294002, a functional inhibitor of SGK1 action. Exposure to LY294002 significantly decreased both CSF-1 and Dex-induced adhesiveness to the level of control cells. SGK1 may act as a downstream intracellular regulator of c-fms, particularly of c-fms-induced adhesiveness of breast cancer cells after exposure to GC or CSF-1. This finding may have implications for potential therapeutic interventions aimed at decreasing the aggressiveness of breast cancer cells.
Clin Exp Metastasis 2004
PMID:SGK1, a potential regulator of c-fms related breast cancer aggressiveness. 1567 45

Oral squamous cell carcinoma (OSCC) is a common worldwide malignancy. However, it is unclear what, if any, genomic alterations occur as the disease progresses to invasive and metastatic OSCC. This study used genomewide array-CGH in microdissected specimens to map genetic alterations found in primary OSCC and neck lymph node metastases. We used array-based comparative genomic hybridization (array-CGH) to screen genomewide alterations in eight pairs of microdissected tissue samples from primary and metastatic OSCC. In addition, 25 primary and metastatic OSCC tissue pairs were examined with immunohistochemistry for protein expression of the most frequently altered genes. The highest frequencies of gains were detected in LMYC, REL, TERC, PIK3CA, MYB, MDR1, HRAS, GARP, CCND2, FES, HER2, SIS, and SRY. The highest frequencies of losses were detected in p44S10, TIF1, LPL, MTAP, BMI1, EGR2, and MAP2K5. Genomic alterations in TGFbeta2, cellular retinoid-binding protein 1 gene (CRBP1), PIK3CA, HTR1B, HRAS, ERBB3, and STK6 differed significantly between primary OSCC and their metastatic counterparts. Genomic alterations in PRKCZ, ABL1, and FGF4 were significantly different in patients who died compared with those who survived. Immunohistochemistry confirmed high PIK3CA immunoreactivity in primary and metastatic OSCC. Higher FGF4 immunoreactivity in primary OSCC is associated with a worse prognosis. Loss of CRBP1 immunoreactivity is evident in primary and metastatic OSCC. Our study suggests that precise genomic profiling can be useful in determining gene number changes in OSCC. As our understanding of these changes grow, this profiling may become a practical tool for clinical evaluation.
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PMID:Array-comparative genomic hybridization to detect genomewide changes in microdissected primary and metastatic oral squamous cell carcinomas. 1667 65

The year 2006 will mark a turning point in the daily management of patients with metastatic renal cell carcinoma. The impact of immunotherapy with interferon-alpha or interleukin-2 has been shown to be restricted to a minority of patients. The growing understanding of molecular mechanisms involved in the pathogenesis of the disease, especially clear-cell carcinoma, has led to the development of multiple targeted therapies with significant clinical benefits. Two compounds that predominantly inhibit the tyrosine kinase activity of the vascular endothelial growth factor receptor have been shown to improve the progression-free survival of patients in first- (sunitinib versus interferon-alpha) or second-line (sorafenib versus placebo) treatment. Temsirolimus, an agent that inhibits the serine-threonine kinase activity of the mammalian target of rapamycin, offers better overall survival than interferon in patients with poor-risk characteristics. Further studies are needed to determine the optimal combinations of these agents in metastatic disease and to assess their impact in the adjuvant setting.
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PMID:Targeted therapies in metastatic renal cell carcinoma: the light at the end of the tunnel. 1718 90

Several comparative genomic hybridization studies provide evidence for overrepresentation of the long arm of chromosome 20 in malignant melanoma. These studies also suggest that chromosome 20q contains genes that may contribute to melanoma pathogenesis. To refine the region of 20q amplification and to identify potential candidate genes involved in melanoma or even in melanoma progression from these regions, we combined fluorescence in-situ hybridization with MYBL2, ZNF217, CYP24 and STK6 specific probes (chromosomal region 20q13.1-q13.2) with high-throughput tissue microarray consisting of 280 primary melanomas and melanoma metastases. Low-level amplification ranging from 0.5 to 2.0% was detected for the tumor-related genes of interest. Higher frequencies of gain when compared with amplification were detected for MYBL2, ZNF217, CYP24 and STK6. Aneusomy of centromere 20 was observed in 29.9% of the analyzed tumors. A significantly higher frequency of ZNF217, CYP24 and STK6 total copy-number increase, as well as aneusomy of centromere 20, was found in the group of metastases when compared with the group of primary melanomas. Despite the technological advantage of fluorescence in-situ hybridization on tissue microarray, which allows refining regions of amplification, we were not able to recognize any of the MYBL2, ZNF217, CYP24 and STK6 genes as a particular relevant gene for melanoma tumorigenesis.
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PMID:Gene-specific fluorescence in-situ hybridization analysis on tissue microarray to refine the region of chromosome 20q amplification in melanoma. 1723 40

Pim kinases are emerging as important mediators of cytokine signalling pathways in hematopoietic cells, and contribute to the progression of certain leukemias and solid tumors. The mRNA expression of pim-1, a putative oncogenic serine-threonine kinase, was determined in non-small cell lung cancer (NSCLC) patients. Sixty-eight patients with potentially curative resections (R0 resections) for NSCLC in histopathological stages I-IIIA were included. An analysis of pim-1 mRNA expression was performed on paired tumor and normal lung tissue samples by quantitative real-time reverse transcriptase-PCR (RT-PCR) standardized for beta-actin. Pim-1 expression in the tumor (median 0.28) was significantly down-regulated (p<0.0001) compared to the paired normal tissue (median 4.96). Immunohistochemistry showed a strong expression of Pim-1 protein in the normal respiratory epithelium and a lower expression in the tumor cells. A significant association between the pim-1 down-regulation and occurrence of lymph node metastases (p=0.05) was detected. The down-regulation of pim-1 mRNA was demonstrated for 59 out of 68 lung cancer patients (86.8%). Down-regulation occurs already in the early stage of NSCLC and is either directly involved in the lymphatic progression in NSCLC or represents a surrogate marker.
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PMID:Frequent down-regulation of pim-1 mRNA expression in non-small cell lung cancer is associated with lymph node metastases. 1869 14

Resistance to anoikis, the subtype of apoptosis triggered by lack of adhesion, contributes to malignant transformation and the development of metastasis. Although several lines of evidence suggest that p53 plays a critical role in anoikis, the pathway(s) that connect cell detachment to p53 remain undefined. Here, through the use of a kinome-wide loss-of-function screen, we identify the serine-threonine kinase SIK1 (salt-inducible kinase 1) as a regulator of p53-dependent anoikis. Inactivation of SIK1 compromised p53 function in anoikis and allowed cells to grow in an anchorage-independent manner. In vivo, SIK1 loss facilitated metastatic spread and survival of disseminated cells as micrometastases in lungs. The presence of functional SIK1 was required for the activity of the kinase LKB1 in promoting p53-dependent anoikis and suppressing anchorage-independent growth, Matrigel invasion, and metastatic potential. In human cancers, decreased expression of the gene encoding SIK1 closely correlated with development of distal metastases in breast cancers from three independent cohorts. Together, these findings indicate that SIK1 links LKB1 to p53-dependent anoikis and suppresses metastasis.
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PMID:SIK1 couples LKB1 to p53-dependent anoikis and suppresses metastasis. 1962 32


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