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)

The retinoid N-(hydroxyphenyl) retinamide (4-HPR) appears to be a promising tool for chemoprevention of breast carcinoma, and clinical trials to evaluate its effect are in progress. However, its action on tumor cells has remained largely undefined. We report here that 4-HPR induced apoptosis and/or differentiation in breast cancer cell lines, independent of hormone receptor status and retinoic acid receptor expression, although it was slightly more efficient in inhibiting proliferation of estrogen receptor-positive cells. 4-HPR up-modulated expression of several differentiation markers (class 1 HLA, laminin, and beta 1 integrin chain) and down-regulated expression of molecules associated with tumor progression, including the p185/HER2 oncoprotein, the epidermal growth factor receptor, and the M(r) 67,000 laminin receptor. These data suggest that 4-HPR could exert a beneficial effect by inhibiting cell proliferation and modulating breast tumor aggressiveness.
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PMID:Modulation of markers associated with tumor aggressiveness in human breast cancer cell lines by N-(4-hydroxyphenyl) retinamide. 754 8

Hepatocyte growth factor (scatter factor) and its receptor, the c-met proto-oncogene product (c-MET), have been implicated in embryogenesis, tissue reorganization, and tumor progression. Little is known, however, of the expression and functional significance of these molecules in prostatic cells and tissue. In this investigation, we assessed the expression of hepatocyte growth factor (HGF) and c-MET in prostatic tissues and cell lines and also determined the effect of purified recombinant HGF on cell proliferation and scattering of prostatic carcinoma cell lines. HGF was expressed by human prostatic stromal myofibroblasts in primary culture but not by three human prostatic carcinoma cell lines (LNCaP, DU 145, and PC-3) as assessed by Northern blot analysis. HGF was also detected by reverse transcriptase-polymerase chain reaction in both benign and malignant tissues from radical prostatectomy specimens. c-MET transcripts were identified by Northern blot in two androgen-insensitive human prostatic carcinoma cell lines (DU 145 and PC-3) but not the androgen-sensitive LNCaP cell line. Additional evidence of linkage of androgen responsiveness and c-MET was provided by experiments in which androgen deprivation of normal rat prostates via castration produced a marked up-regulation of c-MET expression as determined by Northern blot and immunohistochemistry. c-MET protein was detected by immunohistochemical analysis in a substantial percentage (58 of 128 or 45%) of prostatic carcinomas and was found more often in metastatic growths of human prostatic carcinoma (15 of 20 patients) compared with primary tumors (43 of 108 patients; P < 0.005). Moreover, in Dunning R-3327 rat prostatic carcinoma cell lines, c-MET expression was highest in the androgen-insensitive subline with the highest metastatic capacity. Purified recombinant human HGF induced dose-dependent cellular proliferation and scattering in the DU 145 carcinoma cell line. These data indicate that HGF may function in the prostate gland as a paracrine growth factor, with synthesis by stromal cells and with biological target cells being the epithelial cells. Expression of the HGF receptor, c-MET, is up-regulated by androgen deprivation and c-MET appears to be preferentially expressed on androgen-insensitive, metastatic cells, suggesting a possible linkage of c-MET expression with prostatic carcinoma progression.
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PMID:Hepatocyte growth factor and its receptor (c-MET) in prostatic carcinoma. 763 32

The HER2/neu (c-erbB2) protooncogene, which encodes a transmembrane receptor (p185neu), contributes to tumor cell invasion/metastasis through mechanism(s) which are, at present, poorly defined. Since basement membrane degradation is a prerequisite for tumor progression, we undertook a study to determine if the expression of urokinase, a key protease implicated in extracellular matrix proteolysis, was regulated by this oncogene. Stable overexpression of a cDNA encoding HER2/neu in H460 lung cancer cells led to elevated secretion of urokinase which was a consequence of a higher level of protease mRNA. Transfection of the HER2/neu-overexpressing B 104-1 cells with a CAT reporter construct driven by the urokinase promoter, gave rise to increased CAT activity when compared with parental NIH3T3 cells, which have low levels of HER2/neu, suggesting that the protooncogene can enhance urokinase promoter activity. Since the enhanced expression of HER2/neu results in increased tumor invasion/metastasis (1), these data suggest that, at least in vitro, HER2/neu-induced expression of urokinase may contribute to tumor progression in p185neu-positive cancers.
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PMID:Up-regulation of urokinase-type plasminogen activator expression by the HER2/neu proto-oncogene. 765 95

Bax is a homologue of Bcl-2 that promotes apoptosis. Bax protein levels were assessed by immunohistochemical methods in primary tumors derived from 119 women with metastatic breast cancer. These patients had received combination chemotherapy either with a once a month dosage schedule or in 4 weekly divided doses. The BAX immunostaining results were retrospectively compared with overall survival, time to tumor progression (TTP), and response, as well as several laboratory markers. Normal breast epithelium and in situ carcinomas immunostained positively for Bax. Marked reductions in Bax immunostaining were observed in 40 (34%) of 119 evaluable tumors. Reduced Bax correlated with shorter overall survival (median, 8.1 versus 15.7 months; P = 0.04), faster TTP (median, 2.0 versus 6.3 months; P = 0.009), and failure to respond (complete response, partial responses; 6% versus 42%, P = 0.01) in the subgroup of patients who received divided dose therapy. Reduced Bax immunostaining was not significant in the monthly dose group. When the two groups were combined, however, reduced Bax was significantly correlated in univariate analysis with failure to respond (21 versus 43% achieving complete response or partial response; P = 0.02), faster TTP (median, 3.7 versus 9.0 months; P = 0.02), and shorter survival (median, 10.7 versus 17.1 months; P = 0.04). Bax immunostaining was not significantly correlated with tumor histology, S-phase fraction, aneuploidy, p53 HER2, or cathepsin D, but was positively associated with Bcl-2 (P = 0.005). In multivariate analysis (Bax, tumor grade, and treatment group), reduced Bax was strongly associated with faster TTP (P approximately equal to 0.009) and shorter survival (P approximately equal to 0.001). Although highly preliminary, the finding suggest that loss of Bax immunostaining represents a novel prognostic indicator of poor response to chemotherapy and shorter survival in women with metastatic breast cancer, and raise the possibility that the subgroup of women with Bax-negative tumors may benefit from more aggressive therapy.
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PMID:Reduced expression of proapoptotic gene BAX is associated with poor response rates to combination chemotherapy and shorter survival in women with metastatic breast adenocarcinoma. 767 Dec 62

Recently the putative tumor suppressor gene p16INK4 was mapped to human chromosome 9p21, which is homologous to rat chromosome 5. Monosomy of rat chromosome 5 occurs with high frequency in rat kidney tumor-derived cell lines (ERC lines). Thus, we studied these lines in order to investigate the involvement of p15INK4B and p16INK4 in the genesis of this tumor type. p15INK4B and p16INK4 were found by Southern blot analysis to be codeleted in five of seven of these lines. This was confirmed by Northern blot analysis with a probe for the rat p15INK4B gene. In normal rat tissues, expression of p15INK4B was abundant in lung (2.5 and 2.0 kilobases), less abundant in testis (2.5, 2.0, 1.1, and 0.9 kilobases), barely detectable in liver (2.0 kilobases), and not detectable in neonatal kidney, adult kidney, brain, heart, or spleen. In the ERC lines, p15INK4B was expressed as a single 2.0-kilobase transcript observed only in those cell lines in which the gene was detected by Southern blot analysis. However, neither p15INK4B nor p16INK4 were deleted in 12 of 12 primary kidney tumors examined, suggesting that deletion of these genes is not directly involved in the process of renal tumor development but may be related to tumor progression or autonomous growth in vitro. A panel of rat kidney epithelial cell lines chemically transformed in vitro (TRKE lines) that had high-frequency monosomy 5 were also examined, but deletion of p15INK4B and p16INK4 was observed in only one of six of the TRKE lines. To our knowledge, this is the first reported investigation of these genes in rodent tumors and cell lines, and its data support the theory that alterations of genes located in the INF region of rat chromosome 5 may play a role in rodent cell transformation.
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PMID:Association of rat p15INK4B/p16INK4 deletions with monosomy 5 in kidney epithelial cell lines but not primary renal tumors. 771 60

The objective of the present study was to determine the frequency of amplifications of three different members of the erbB gene family in human glioblastoma multiforme (GBM). We investigated 47 glial tumors (37 GBM WHO grade IV, 5 anaplastic astrocytomas WHO III and 5 astrocytomas WHO II) by Southern and Western analysis, and immunocytochemistry. Gene amplification of erbB genes in human malignant gliomas was restricted to the EGF receptor (EGFR) gene, erbB-1. We found amplification of the EGFR gene in 49% (18/37) of GBM but not in the astrocytomas WHO II/III. The erbB-2 and erbB-3 genes showed no amplification in the tumor specimens investigated in this study. At the protein level we found overexpression of the EGF receptor in 86% (32/37) by Western analysis and in 92% (34/37) by immunocytochemistry. Expression of the ERBB2 protein was present in 54% (20/37) but immunoreactivity was much weaker than for EGF receptor and in most cases barely detectable by Western analysis and immunocytochemistry. The ERBB3 protein was not expressed in the glial tumors investigated in this study. Of the three erbB genes only gene amplification and overexpression of the EGF receptor seems to have an impact on tumor progression of human gliomas. Our data from immunohistochemistry indicate that ERBB2 expression in GBM is closely correlated with EGF receptor levels and is therefore not useful as an independent prognostic parameter.
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PMID:Amplification and differential expression of members of the erbB-gene family in human glioblastoma. 776 96

Protein tyrosine kinases have been implicated in tumor initiation and progression. Here we used Northern blotting to study expression of their genes in cultured normal melanocytes and 19 melanoma cell lines from different stages of tumor progression. We detected transcripts for 2 cytoplasmic (ABL and FES) and 6 receptor (ECK, ERB-B2, FGF-R4, IGFI-R, KDR and TIE) kinases but not for receptors RET or TRK-A. Genes for ECK, FGF-R4 and TIE were expressed ectopically in melanomas (not in normal melanocytes). Similarly, ECK protein was detected by immunoblotting in metastatic melanomas but not in normal melanocytes. ECK mRNA levels tended to increase again during late melanoma progression. ECK and TIE mRNAs were also detected in highly metastatic variant cells but not in the corresponding poorly metastatic parental lines. Conversely, FES and KDR gene expression was lost in most advanced primary and metastatic melanomas. These findings suggest positive and negative roles for specific tyrosine kinases during progression.
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PMID:Abnormal protein tyrosine kinase gene expression during melanoma progression and metastasis. 781 45

Key growth factor-receptor interactions involved in angiogenesis are possible targets for therapy of CNS tumors. Vascular endothelial growth factor (VEGF) is a highly specific endothelial cell mitogen that has been shown to stimulate angiogenesis, a requirement for solid tumor growth. The expression of VEGF, the closely related placental growth factor (PIGF), the newly cloned endothelial high affinity VEGF receptors KDR and FLT1, and the endothelial orphan receptors FLT4 and Tie were analyzed by in situ hybridization in normal human brain tissue and in the following CNS tumors: gliomas, grades II, III, IV; meningiomas, grades I and II; and melanoma metastases to the cerebrum. VEGF mRNA was up-regulated in the majority of low grade tumors studied and was highly expressed in cells of malignant gliomas. Significantly elevated levels of Tie, KDR, and FLT1 mRNAs, but not FLT4 mRNA, were observed in malignant tumor endothelia, as well as in endothelia of tissues directly adjacent to the tumor margin. In comparison, there was little or no receptor expression in normal brain vasculature. Our results are consistent with the hypothesis that these endothelial receptors are induced during tumor progression and may play a role in tumor angiogenesis.
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PMID:Expression of endothelial cell-specific receptor tyrosine kinases and growth factors in human brain tumors. 785 49

To study genetic alterations related to the development and/or progression of breast carcinoma, we examined amplification of the ERBB2, INT2, and MYC genes, as well as loss of heterozygosity (LOH) at loci on 11p, 16q, 17p (D17S5 and TP53), 17q (D17S74 and NME1), and 18q by restriction fragment length polymorphism analysis. The subjects were 26 patients with small breast carcinomas (< or = 2 cm) and 88 patients with larger breast carcinomas (2 to < 5 cm). All patients were free of distant metastasis. As tumor diameter increased, the frequency of oncogene amplification and LOH at all loci except D17S5 increased. However, there was no relationship between tumor diameter and amplification of specific oncogenes or allelic loss at specific loci. LOH at D17S5 was detected in 40% of small breast carcinomas (< or = 2 cm) and 43% of larger breast carcinomas (2 to < 5 cm). There was a significant correlation of LOH at D17S5 with INT2 amplification or with LOH on 11p, 16q, and 18q. These findings suggest that LOH at D17S5 may be involved in the early stage of breast carcinoma development, while INT2 amplification and LOH at 11p, 16q, and 18q appear to be genetic alterations that occur with tumor progression. In addition, as lymph node metastases were significantly related to amplification of the ERBB2 and MYC genes, and LOH of the NME1 gene, these genetic alterations may play a role in the mechanism of lymph node metastases.
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PMID:Analysis of genetic alterations related to the development and progression of breast carcinoma. 790 63

Metastatic phenotype in human solid tumors is believed to follow stochastic acquisition of structural genetic aberrations-so-called multistep tumor progression. We tested this hypothesis in breast carcinoma by immunostaining 89 stage-heterogeneous cases for the products of three genes (p53, ERBB-2, and EGFR) which are frequently altered in this tumor system. Variable relationships were observed between advanced disease stage and immunostaining for individual gene products (ERBB-2 - p = 0.05, EGFR - p = 0.02, p53 - p = 0.12, Chi Square test). Regional or distant metastases at presentation correlated with multiple oncogene/tumor suppressor gene expression abnormalities: node negative -59% none positive, 29% one positive, 12% two or more positive, vs. node positive -37% none positive, 23% one positive, 39% two or more positive (p = 0.01). Only 2/12 (17%) of tumors with distant metastases at presentation were negative for abnormal expression of any of these gene products, and 7/12 (58%) were positive for two or three. Among axillary node negative patients who developed recurrences, 67% exhibited staining for at least one gene product, compared to only 27% of those without recurrences (p = 0.02). All 5 cases with abnormal staining for each gene product had regional or distant metastases at presentation and recurred. In multivariate analysis, individual expression of p53 outweighed expression of ERBB-2 and EGFR in correlation with outcome. These data suggest clinical neoplastic progression of breast carcinomas correlates with cumulative genetic events detectable by protein expression. Short term recurrence, however, may correlate more closely with abnormal expression of p53 than with EGFR or ERBB-2.
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PMID:Concurrent abnormal expression of ERBB-2, EGFR, and p53 genes and clinical disease progression of breast carcinoma. 791 62


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