Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pancreatic cancer has one of the poorest prognoses of all gastrointestinal malignancies. Today, it is the fourth or fifth leading cause of cancer-related deaths in Western industrialized countries, and the incidence has been increasing throughout the past decades. Insensitivity to growth-inhibitory and apoptotic signals as well as self-sufficiency of growth-promoting factors are hallmarks of the pathogenesis of this malignancy. In pancreatic cancer, a variety of growth factors and their receptors are expressed at increased levels. For example, the concomitant presence of the epidermal growth factor (EGF) receptor and its ligand EGF is associated with enhanced tumor aggressiveness and shorter survival following tumor resection. Furthermore, a number of other growth factors and their receptors, such as nerve growth factor and its receptor, are overexpressed in pancreatic cancer and contribute to its malignant phenotype. Besides factors which directly promote cell proliferation, a variety of other factors such as galectins are upregulated, which influences the tumor environment and the invasiveness of pancreatic cancer cells. In addition, tumor suppressor genes such as KAI1 are expressed at reduced levels, thereby enhancing the ability of pancreatic cells to form metastases. A complex disturbance of factors is present in pancreatic cancer, resulting in a distinct growth advantage which clinically results in rapid tumor progression and poor patient survival.
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PMID:Pancreatic cancer: factors regulating tumor development, maintenance and metastasis. 1212 Feb 31

A novel approach to cancer gene therapy is to implant microcapsules containing nonautologous cells engineered to secrete molecules with antineoplastic properties. The efficacy of this treatment is now tested in a mouse model bearing HER-2/neu-positive tumors. Nonautologous mouse myoblasts (C(2)C(12)) were genetically modified to secrete interleukin-2 linked to the Fv region of a humanized antibody with affinity to HER-2/neu. The resulting fusion protein, sFvIL-2, would encompass immune-stimulatory cytokine activity now targeted to the HER-2/neu-expressing tumor. These recombinant cells were then immunoprotected with alginate-poly-L-lysine-alginate microcapsules before implantation into tumor-bearing mice. Treatment with these encapsulated cells led to a delay in tumor progression and prolonged survival of the animals. The long-term efficacy was limited by an inflammatory reaction against the implanted microcapsules probably because of the secreted cytokine and antigenic response against the xenogeneic fusion protein itself. However, over the short term (initial 2 weeks), efficacy was confirmed when a significant amount of biologically active interleukin-2 was detected systemically, and targeting of the fusion protein to the HER-2/neu-expressing tumor was shown immunohistochemically. The tumor suppression in the treated animals was associated with increased apoptosis and necrosis in the tumor tissue, thus demonstrating successful targeting of the antiproliferative effect to the tumors by this delivery paradigm. In conclusion, this new approach to systemic cancer gene therapy needs to be modified to provide long-term delivery, but has demonstrated short-term efficacy and potential to become a cost-effective, benign, and non-viral-based adjunct to the current armory of anticancer strategies.
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PMID:A novel approach to tumor suppression with microencapsulated recombinant cells. 1213 69

Overexpression of the c-erbB-2 protein (also called HER-2/neu) is observed in a variety of malignancies including colorectal cancer (CRC). In this study we aimed to evaluate the rate of c-erbB-2 overexpression in our tumor collection and to clarify its correlation with the chromosomal status at the c-erbB-2 locus in CRC. Additionally we correlated the c-erbB-2 overexpression and the chromosomal gain of 17q with patient survival. Seventy-four specimens were analyzed immunohistochemically using a polyclonal c-erbB-2 antibody (DAKO) and the staining was scored according to the Clinical Trial Assay recommendations (0-3+). Of these, 45 cases were analyzed by comparative genomic hybridization (CGH) and immunohistochemistry (IHC). Overexpression was observed in 51% of the cases (score > or = 2). Chromosomal gains at the c-erbB-2 locus were clearly correlated with overexpression of the gene (P = 0.0009). Furthermore Kaplan-Meier analysis showed that overexpression of c-erbB-2 was significantly associated with poor survival and thus could serve as a prognostic marker. We conclude that c-erbB-2 is related with tumor progression in CRC which can be observed on protein level and reflects chromosomal gain at the locus at 17q.
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PMID:Overexpression of c-erbB-2 protein correlates with chromosomal gain at the c-erbB-2 locus and patient survival in advanced colorectal carcinomas. 1219 68

To investigate at the population level the impact of BRCA1/BRCA2 gene alterations in male breast cancer, we analyzed a population-based series of 25 male breast cancer cases from Florence, Central Italy. We combined mutational screening with the study of germ-line allele transcript levels and of tumor-associated losses of heterozygosity. Screening by protein truncation test and single-strand conformational polymorphism assay, followed by sequencing, revealed 4 pathogenetic mutations (4 of 25 = 16%; 95% confidence interval, 5-37%), 1 in BRCA1 and 3 in BRCA2, including mutations recurring in Central Italy (BRCA1 3345delAG and BRCA2 6696delTC). The a priori probability of carrying a mutation, estimated using BRCAPRO software, showed a good agreement between expected and observed mutations (14% versus 16%). A 7-fold association between germ-line mutations and family history of breast-ovarian cancer emerged. To investigate associations between BRCA1/BRCA2 status and clinicopathological characteristics, we analyzed the histopathological and immunophenotypic parameters of the tumors. A significant association emerged between mutation carrier status and high histological grade (P = 0.02). Furthermore, one BRCA2 carrier was affected with Paget's disease, an extremely rare male breast cancer histotype. Overall, BRCA1/2 mutations were observed to be strongly associated with positive c-erbB-2 immunostaining (P = 0.004). To evaluate germ-line allele expression, we used primer extension assays targeting frequent BRCA1 and BRCA2 polymorphisms. A BRCA2 allele transcript imbalance was found in one of four heterozygotes tested, all of them negative for germ-line mutations. BRCA1 transcript imbalances were not detected in nine heterozygotes analyzed. Losses of heterozygosity at one or more of nine loci in the BRCA2 region were found in 8 of 22 tumors tested. Interestingly, a case that was negative for BRCA1/BRCA2 germ-line mutations and that had a priori mutation probability <10% showed loss of heterozygosity at all three of the intragenic BRCA2 markers analyzed, which could be related to a somatic involvement of BRCA2. No losses of heterozygosity were detected at BRCA1. In conclusion, constitutional BRCA1/BRCA2 mutations accounted for 16% of the male breast cancer cases in this area of Central Italy. The detection of a BRCA2 germ-line transcript imbalance and of a somatic loss of BRCA2 among the cases that resulted negative for germ-line mutations suggests a role of this gene more relevant than indicated by conventional mutational analysis. A distinct pattern of characteristics indicative of aggressive behavior, including high-grade and c-erbB-2 expression, was evident in tumors from germ-line BRCA2 mutation carriers. This suggests that phenotypic characteristics may contribute to the identification of hereditary BRCA2-related male breast cancers and that these tumors might share a unique molecular pathway of cancer progression.
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PMID:BRCA1 and BRCA2 mutation status and tumor characteristics in male breast cancer: a population-based study in Italy. 1254 86

Breast carcinomas represent a heterogeneous group of tumors, with a diverse biologic behavior, outcome, and response to therapy. Recent studies have demonstrated that alterations in the expression of adhesion molecules in cancer cells are related to aggressiveness and poor prognosis. The aim of our study was to investigate the expression of P-cadherin in breast carcinomas and correlate it with estrogen receptor (ER) status. We selected 73 ductal carcinomas in situ (DCIS) and 149 invasive carcinomas of the breast, and assessed the expression of P-cadherin as well as other biologic markers. P-cadherin expression showed a strong inverse correlation with ER expression in both types of breast carcinoma (in situ and invasive). P-cadherin-positive and ER-negative tumors were related to a higher histologic grade, a high proliferation rate, and expression of c-erbB-2. We demonstrated that P-cadherin identifies a subgroup of breast carcinomas that lacks ER expression, and correlates with higher proliferation rates and other predictors of aggressive behavior. We believe that these tumors represent an advanced step in cancer progression, and our data support the hypothesis that an estrogen-independent pathway regulates P-cadherin expression.
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PMID:Aberrant P-cadherin expression: is it associated with estrogen-independent growth in breast cancer? 1260 56

Our report describes a 66-yr-old man who underwent surgical resection of the pancreas twice within a period of 3 yr for primary and recurrent intraductal papillary mucinous tumors (IPMTs). During the second operation, a minute invasive ductal carcinoma (IDC) was accidentally discovered in the resected specimen of the residual pancreas. The similarity and continuity between this IDC and recurrent IPMT were not recognized histologically. A solid tumor was found in the hepatoduodenal ligament 3 mo after the second operation. We performed a third operation, performing laparotomy and intra-operative radiotherapy, but could not extirpate the tumor. A biopsy specimen obtained from the tumor during this third operation revealed adenocarcinoma, and the patient later died because of tumor progression. We immunohistochemically analyzed the expression of HER-2/neu, Smad4, p16, p21, p53, mucin immunophenotypes and the Ki-67 labeling index in this series of pancreatic-duct neoplasias. Overexpression of HER-2/neu and loss of Smad4 were detected in the minute IDC, which was very different from the immunohistochemical features of both the primary and recurrent IPMTs. The IDC also showed a MUC1-positive/MUC2-negative phenotype. Therefore, we suggest that de novo IDC may occur in IPMT patients, especially those with multiple tumor recurrence. The present case may be helpful in understanding the pathogenesis of pancreatic duct lesions.
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PMID:Minute invasive ductal carcinoma of the residual pancreas after distal pancreatectomy for intraductal papillary-mucinous tumor. 1262 31

Drug resistance to tamoxifen (Tam) is a significant clinical problem but the mechanism through which this occurs remains elusive. We have developed a number of xenograft models of Tam-stimulated growth that model breast cancer progression using estrogen receptor positive MCF-7 or T47D breast cancer cells. When estrogen-stimulated T47D:E2 tumors are treated long term with Tam, Tam-stimulated tumors develop (T47D:Tam) that are stimulated by both estrogen and Tam. When HER-2/neu status is determined, it is clear that the T47D:Tam tumors express significantly higher levels of HER-2/neu protein by immunohistochemistry and mRNA as measured by real-time RT-PCR. The T47D:Tam tumors also express higher levels of estrogen receptor and progesterone receptor protein than their estrogen-stimulated T47D:E2 counterparts. We compared out results to the MCF-7 model of Tam-stimulated growth. The MCF-7:Tam ST (estrogen- and Tam-stimulated) and MCF-7:Tam LT (estrogen-inhibited, Tam-stimulated) were bilaterally transplanted to account for any mouse to mouse variation and characteristic growth patterns were observed. TUNEL staining was performed on MCF-7:Tam LT treated with either estrogen or Tam and it was concluded that estrogen-inhibited tumor growth was a result of increased apoptosis. Three phases of tumor progression are described that involve increases in HER-2/neu expression, de-regulation of estrogen receptor expression and increases in apoptosis which in concert determine the phenotype of drug resistance to Tam.
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PMID:A mechanism of drug resistance to tamoxifen in breast cancer. 1265 Jul 3

Oncogenes, the abnormal forms of proto-oncogenes, were shown to be involved in malignant transformation and in tumor progression. c-erbB2/HER2/neu is member of EGFR family and encodes the p185 protein, which functions as a tyrosine-kinase. Gene amplification and/or p185 overexpression were reported to be associated with poor prognostic in cancer. Our purpose was to investigate p185 immunohistochemical expression in breast carcinomas and in the corresponding axillary lymph nodes metastases and to identify possible correlation between p185 and other factors of poor prognostic, such as loss of hormonal receptors expression. In our study, 40.91% of cases were erbB-2 positive, p185 expression being maintained from the primary tumors to axillary metastases and associated with positive nodal status and with the absence of hormonal receptors expression (p < 0.05). These findings support the hypothesis the c-erbB2 is an advantageous acquisition for the aggressive behavior of the tumor cell and for its ability to invade and metastasize.
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PMID:[Overexpression of c-erbB-2 gene product is associated with poor prognosis factors in breast carcinoma]. 1475 39

c-erbB-2, proto-oncogene is amplified and overexpressed in a number of human adenocarcinomas. Overexpression of c-erbB-2 is indicated as a worse prognostic factor and associated with neoplastic progression in various organs. To investigate the therapeutic effect of Trastuzumab in gallbladder cancer, we studied HER-2/neu expression in 43 primary tumors, 12 metastatic lymph nodes and two liver metastasis, using the Hercep test. Among primary tumors, strong (3+) immunohistochemical intensity was found in two cases (4.7%), weak (2+) in two (4.7%) and negative (1+) (2.3%) in one case. This positivity rate was distinctly lower than those in previous reports. There was no tendency between clinicopathologic characteristics and HER-2 positivity in the primary gallbladder. Among 12 metastatic lymph nodes, only one specimen showed 2+ positivity where the primary lesion revealed 3+ intensity of HER-2. In two liver metastatic lesions, the expression of HER-2 was not found. Our study implied that Trastzumab may not contribute to improvement in treatment of gallbladder cancer. However, there may be a therapeutic possibility for cases with lymph node recurrence overexpressing c-erbB-2.
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PMID:Gallbladder cancers rarely overexpress HER-2/neu, demonstrated by Hercep test. 1501 Aug 78

It has been previously demonstrated that human ovarian cancer cells express FSH receptor (FSHR). However, whether FSHR plays a role in ovarian cancer development is still ambiguous. To investigate the role of FSHR in tumor progression, we overexpressed the receptor in SV40 Tag immortalized ovarian surface epithelium (OSE) cell lines (IOSE-80PC, a postcrisis line, and IOSE-398), which are preneoplastic and nontumorigenic. We compared the expression levels of several selected oncogenes in nontransfected (80PC), vector-transfected (80PCV), FSHR-transfected IOSE (80PCF) cells, and established ovarian cancer cell lines (OVCAR-3 and SKOV-3). Significantly increased protein levels of epithelial growth factor receptor, HER-2/neu, and c-Myc, but not K-Ras, were observed in FSHR-overexpressing 80PCF cells when compared with 80PCV cells. Constitutive phosphorylation of ERK1/2 was augmented in 80PCF cells, whereas phosphorylation of the other MAPK including p38 and Jun N-terminal kinase was unchanged. Considerable constitutive phosphorylation of ERK1/2 was also observed in OVCAR-3 and SKOV-3 cell lines when compared with 80PCV. More importantly, 80PCF cells grew more rapidly than 80PC and 80PCV cells. In conclusion, we have demonstrated that FSHR was highly expressed in OVCAR-3 and 80PCF cells transfected with FSHR overexpression vector. The 80PCF cell line showed increased levels of epithelial growth factor receptor, HER-2/neu, and c-myc and constitutive activation of ERK1/2. The rate of proliferation of the 80PCF cells was increased, compared with control cell lines. These results suggest that the overexpression of FSHR may be associated with enhanced levels of potential oncogenic pathways and increased proliferation in preneoplastic ovarian surface epithelial cells.
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PMID:Overexpression of follicle-stimulating hormone receptor activates oncogenic pathways in preneoplastic ovarian surface epithelial cells. 1553 6


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