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)

In spite of the established knowledge of the genetic alterations responsible for cancer onset, the genes promoting and maintaining the invasive/metastatic phenotype are still elusive. The MET proto-oncogene, encoding the tyrosine kinase receptor for hepatocyte growth factor (HGF), senses unfavorable micro-environmental conditions and drives cell invasion and metastasis. MET overexpression, often induced by tumor hypoxia, leads to constitutive activation of the receptor and correlates with poor prognosis. To establish the role of MET in different phases of tumor progression, we developed an inducible lentiviral delivery system of RNA interference. Silencing the endogenous MET gene, overexpressed in tumor cells, resulted in (i) impairment of the execution of the full invasive growth program in vitro, (ii) lack of tumor growth and (iii) decreased generation of experimental metastases in vivo. Notably, silencing MET in already established metastases led to their almost complete regression. This indicates that persistent expression of the MET oncogene is mandatory until the advanced phases of cancer progression.
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PMID:Silencing the MET oncogene leads to regression of experimental tumors and metastases. 1768 86

The proto-oncogene c-kit is known to be expressed in poorly differentiated breast cancer. In this study, we retrospectively evaluated the prognostic and predictive impact of c-kit in a high risk subgroup of breast cancer patients (>9 axillary node metastases) who received high-dose (HDCT) or dose-dense (DDCT) conventional chemotherapy and correlated these findings with the expression of the basal-type markers CK5 and CK 17, estrogen (ER) and progesterone (PR) receptor, Her-2/neu and MIB 1. C-kit, CK5, CK17, ER, PR, Her-2/neu and MIBI expression was evaluated immunohistochemically using tissue microarrays containing breast cancer samples from 236 patients who were randomized to the WSG AM01 trial (median follow-up of 60 months). There was a significant overall survival (OS) benefit for patients receiving HDCT compared to DDCT (p = 0.027). C-KIT expression was found in 12 % of all breast cancers and correlated with a poorer OS in multivariate analysis (p = 0.051). Furthermore, c-kit correlated with high grade (p = 0.019), CK5- and CK17-positivity (p <0.0001 and p = 0.001, respectively) and ER- and PR-negativity (p = 0.04 and p = 0.008, respectively). In contrast to CK5 and CK17, patients with c-kit positive breast cancers revealed no benefit from high-dose chemotherapy. These findings underline that c-kit expression represents an independent negative prognostic marker in high-risk breast cancer. Correlation with CK5 +/CK17+ and ER-/PR-suggests that c-kit positive carcinomas are at least partly of basal-type.
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PMID:C-kit expression in high-risk breast cancer subgroup treated with high-dose or conventional dose-dense chemotherapy. 1786 95

Medullary thyroid carcinoma (MTC) accounts for up to 8% of all thyroid cancers. Although primary surgery is curative in the vast majority of patients treated at an early stage, disease can persist or recur with deleterious effects on quality of life. Local and distant metastases can occur and are the major causes of mortality. Reoperation, embolization, and perhaps radiotherapy can improve the outcome for some patients who are not cured by primary surgery, but there is a need for novel treatments. No comprehensive clinical trial data are available on conventional cytotoxic agents for the treatment of MTC. Patients with distant metastases, in particular, might benefit from several novel compounds directed against angiogenesis and molecular targets in tumor cells, such as products of the proto-oncogene RET and mutants of it, and other signaling components. Well-conducted clinical trials are needed to assess and optimize these treatment strategies, and this article outlines how such trials should be conducted. Although RET mutations are common in hereditary MTC and can occur in some cases of sporadic MTC, knowledge of other molecular defects associated with the development of MTC should reveal new targets for therapy.
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PMID:New therapeutic approaches to treat medullary thyroid carcinoma. 1808 43

Diverse cellular processes are regulated by tyrosyl phosphorylation, which is controlled by protein-tyrosine kinases (PTKs) and protein-tyrosine phosphatases (PTPs). De-regulated tyrosyl phosphorylation, evoked by gain-of-function mutations and/or over-expression of PTKs, contributes to the pathogenesis of many cancers and other human diseases. PTPs, because they oppose the action of PTKs, had been considered to be prime suspects for potential tumor suppressor genes. Surprisingly, few, if any, tumor suppressor PTPs have been identified. However, the Src homology-2 domain-containing phosphatase Shp2 (encoded by PTPN11) is a bona fide proto-oncogene. Germline mutations in PTPN11 cause Noonan and LEOPARD syndromes, whereas somatic PTPN11 mutations occur in several types of hematologic malignancies, most notably juvenile myelomonocytic leukemia and, more rarely, in solid tumors. Shp2 also is an essential component in several other oncogene signaling pathways. Elucidation of the events underlying Shp2-evoked transformation may provide new insights into oncogenic mechanisms and novel targets for anti-cancer therapy.
Cancer Metastasis Rev 2008 Jun
PMID:The tyrosine phosphatase Shp2 (PTPN11) in cancer. 1828 34

Estrogens are important for stimulating the growth of a large proportion of breast cancers. Progesterone plays critical roles in breast development and tumorigenesis. The c-erbB2 gene (HER-2/neu) is a proto-oncogene expressed in 10-34% of breast cancers. Its expression is associated with poor clinical outcome. The hypothesis that the progression of in situ ductal carcinoma of breast to invasive ductal carcinoma is associated with alterations of ER, PgR and HER-2/neu protein expression was tested. Of 100 mastectomy specimens examined, all contained both ductal carcinoma in situ (DCIS) and invasive ductal carcinomas (IDC) not otherwise specified (NOS). The status of ER, PgR and HER-2/neu proteins was examined by immunochemistry. ER and PgR protein expression was scored as the mean value of positively stained cells. HER-2/neu protein expression was evaluated on ts staining pattern (0, 1+, 2+ and 3+). We found variations between DCIS and IDC with significant decrease of the mean values of ER and PgR positively stained cells in high-grade (Grade 3) IDC (ER: 49.2+/-10.3 vs. 30.8+/-5.5 and PgR: 40.0+/-10.0 vs. 22.3+/-5.1 in DCIS and IDC, respectively, P<0.05). Invasive carcinomas with lymph node metastases or lymphovascular invasion or both had lower mean values of ER and PgR positively stained cells compared to those without these features. In IDC (Grade 3), HER-2/neu protein expression values (1.2+/-0.2) were significantly high compared to DCIS (0.7+/-0.3, P<0.05). In addition, HER-2/neu protein expression values were significantly higher (P<0.05) in IDC with lymph node metastases or lymphovascular invasion (1.5+/-0.3) than those without these features (0.8+/-0.2). A significantly high mean (P<0.05) of ER and PgR positively stained cells was observed in postmenopausal females compared to premenopausal women. In contrast, high HER-2/neu expression values were seen only in premenopausal females. A significant positive correlation was observed between ER and PgR receptor expression (r=0.81). A low degree inverse correlation (r=-0.24, P<0.012) was found between ER+/PgR+ tumors and HER-2/neu expression. These findings substantiate the notion that breast cancer progression is often associated with alterations of ER, PgR and HER-2/neu expression. The underlying mechanisms of these alterations are open for further investigation.
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PMID:Alterations of estrogen receptors, progesterone receptors and c-erbB2 oncogene protein expression in ductal carcinomas of the breast. 1829 77

c-Src is a proto-oncogene involved in the genesis of and invasion by many cancers. This non-receptor tyrosine kinase also plays a crucial role in bone homeostasis, since inhibition or deletion of c-Src impairs the function of osteoclasts, the bone resorbing cells. It is thus conceivable that c-Src could be a suitable target for the pharmacological treatment of cancers, skeletal metastases and diseases of bone loss, such as osteoporosis. The pyrrolo-pyrimidines CGP77675 and CGP76030 proved to be effective in preventing bone loss in animal models, while the effect of AZD0530, a dually active inhibitor of c-Src and Bcr-ABL, on bone resorption, has been tested in a Phase I clinical trials with promising results. As far as the metastatic bone disease is concerned, c-Src inhibitors could potentially have inhibitory effects both on osteoclasts and on tumour cells, and could disrupt the vicious circle established between these cell types in the bone microenvironment. In accord with this idea, CGP76030 is able to reduce the incidence of osteolytic lesions and of visceral metastases, and to suppress morbidity and lethality in a bone metastasis mouse model without obvious adverse effects. The purine-based c-Src inhibitor AP23451 and the dual c-Src/Abl inhibitors AP22408 and AP23236 proved efficacious in reducing bone metastases in preclinical studies. These results open a new avenue for the development of innovative therapies for the treatment of bone metastatic disease.
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PMID:Inhibition of protein kinase c-Src as a therapeutic approach for cancer and bone metastases. 1839 92

The c-Met proto-oncogene encodes a receptor tyrosine kinase (TK) that promotes invasive tumor growth and metastasis. Recent studies show that the presence of c-Met gene amplification is predictive for selective c-Met TK inhibitors in gastric cancer and lung cancer. In this study, we utilized a highly quantitative PCR/ligase detection reaction technique to quantify c-Met gene copy number in primary colorectal cancer (CRC) (N=247), liver metastases (N=147), and paired normal tissues. We identified no differences in c-Met gene copy number between normal colonic mucosa and liver tissue. However, mean c-Met gene copy number was significantly elevated in CRC compared with normal mucosa (P<0.001), and in liver metastases compared with normal liver (P<0.001). Furthermore, a significant increase in c-Met was seen in liver metastases compared with primary CRC (P<0.0001). c-Met gene amplification was observed in 2% (3/177) of localized cancers, 9% (6/70) of cancers with distant metastases (P<0.02), and 18% (25/147) of liver metastases (P<0.01). Among patients treated by liver resection, there was a trend toward poorer 3-year survival in association with c-Met gene amplification (P=0.07). Slight increases in c-Met copy number can be detected in localized CRCs, but gene amplification is largely restricted to Stage IV primary cancers and liver metastases. c-Met gene amplification is linked to metastatic progression, and is a viable target for a significant subset of advanced CRC.
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PMID:c-Met gene amplification is associated with advanced stage colorectal cancer and liver metastases. 1839 71

Colon cancer arises through a multistep process involving inactivation of tumor suppressor proteins and activation of oncogene-encoded proteins. Development of colon cancer frequently involves mutation of the adenomatous polyposis coli (APC) tumor suppressor. The activity of the proto-oncogene-encoded Src tyrosine kinase is commonly elevated in colon cancer, with higher activity observed as tumors progress and metastasize. Both APC and Src are multifunctional proteins that have been implicated in the control of cell proliferation, but also as regulators of cytoskeletal changes associated with cell motility and invasion. To investigate the potential for biological cooperativity between APC partial loss-of-function and Src gain-of-function, oncogenic Src was stably expressed in mouse colon epithelial cell lines IMCE (APC(+/min)) and YAMC (APC(+/+)). Under permissive growth conditions, these lines are conditionally immortalized through inactivation of p53. Irrespective of the APC genotype or p53 status, oncogenic Src expression led to morphologic transformation associated with loss of cell-cell junctions, cytoskeletal disorganization, and acquisition of invasive properties. However IMCE cells that carry one copy of the mutant APC(min) allele exhibited increased capacity for Src-mediated anchorage-independent proliferation as compared to the YAMC cells, and this property was enhanced under permissive growth conditions. beta-catenin levels and transcriptional activity were also elevated in the Src-transformed IMCE cells. The selective Src inhibitor, AZD0530, was found to be effective in blocking both cell invasion and anchorage-independent proliferation. These findings suggest that the combined effects of elevated Src activity and APC partial loss-of-function may contribute to the growth of colon tumors.
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PMID:Src transformation of colonic epithelial cells: enhanced anchorage-independent growth in an Apc(+/min) background. 1861 32

Colorectal cancer is the second leading cause of cancer-related deaths in the United States. Understanding the distinct genetic and epigenetic changes contributing to the establishment and growth of metastatic lesions is crucial for the development of novel therapeutic strategies. In a search for key regulators of colorectal cancer metastasis establishment, we have found that the serine/threonine kinase Akt2, a known proto-oncogene, is highly expressed in late-stage colorectal cancer and metastatic tumors. Suppression of Akt2 expression in highly metastatic colorectal carcinoma cells inhibits their ability to metastasize in an experimental liver metastasis model. Overexpression of wild-type Akt1 did not restore metastatic potential in cells with downregulated Akt2, thus suggesting non-redundant roles for the individual Akt isoforms. In contrast, Akt2 overexpression in wild-type PTEN expressing SW480 colorectal cancer cells led to the formation of micrometastases; however, loss of PTEN is required for sustained formation of overt metastasis. Finally, we found that the consequence of PTEN loss and Akt2 overexpression function synergistically to promote metastasis. These results support a role for Akt2 overexpression in metastatic colorectal cancer and establish a mechanistic link between Akt2 overexpression and PTEN mutation in metastatic tumor establishment and growth. Taken together, these data suggest that Akt family members have distinct functional roles in tumor progression and that selective targeting of the PI3K/Akt2 pathway may provide a novel treatment strategy for colorectal cancer metastasis.
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PMID:Akt2 overexpression plays a critical role in the establishment of colorectal cancer metastasis. 1907 30

Gastrointestinal stromal tumors (GISTs) are a rare and heterogeneous group of spindle cell neoplasms that have also been reported outside of gastrointestinal (GI) tract. These tumors are characterized by somatic mutations of c-KIT (CD117), a proto-oncogene that encodes a receptor tyrosine kinase normally expressed in the interstitial cell of Cajal that control the GI smooth muscle peristalsis, and an exquisite sensitivity to the action of the tyrokinase inhibitor imatinib mesylate (STI571; Gleevec). We report two cases of gastrointestinal stromal tumor identified on prostatic biopsies, where a primary prostatic sarcoma was considered in the differential diagnosis. In one of the cases, there was extensive local disease involving prostate, rectum, and pelvic wall, as well as metastatic disease that quickly lead to the patient's death despite aggressive treatment with imatinib mesylate and conventional chemotherapy. In the other case, the tumor was mostly confined to the rectum but also focally extended into the prostate capsule. The patient underwent resection and was alive without disease 18 months after surgery. In both cases, tissue samples from prostate and the rectum showed a malignant spindle cell neoplasm, which was positive for CD117 (c-kit). Given their unique clinical management, gastrointestinal stromal tumors should be considered in the differential diagnosis of spindle cell lesions on prostatic needle biopsies and CD117 should be added to the immunohistochemical panel in the work-up of such lesions to avoid misinterpreting them as primary prostatic neoplasms.
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PMID:Gastrointestinal stromal tumors presenting as a prostatic mass. 1922 92


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