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

Acquisition of invasive/metastatic potential through protease expression is an essential event in tumor progression. High levels of components of the plasminogen activation system, including urokinase, but paradoxically also its inhibitor, plasminogen activator inhibitor 1 (PAI1), have been correlated with a poor prognosis for some cancers. We report here that deficient PAI1 expression in host mice prevented local invasion and tumor vascularization of transplanted malignant keratinocytes. When this PAI1 deficiency was circumvented by intravenous injection of a replication-defective adenoviral vector expressing human PAI1, invasion and associated angiogenesis were restored. This experimental evidence demonstrates that host-produced PAI is essential for cancer cell invasion and angiogenesis.
 ...
PMID:Absence of host plasminogen activator inhibitor 1 prevents cancer invasion and vascularization. 970 Dec 44

This study was aimed at testing the hypothesis that the expression of proteases essentially produced by reactive stromal cells (stromelysin-3 [ST3], gelatinase A [GELA], and urokinase [uPA]) is predictive of prognosis in patients with breast cancer. This was a study of patients with node-positive and node-negative breast cancer diagnosed from 1980 to 1986 and with an average of 10 years follow-up. ST3 (665 cases), GELA, and uPA (575 cases each) expression was obtained by in situ hybridization on formalin-fixed, paraffin-embedded material using mRNA antisense probes. ST3 was expressed by 86.6% of the cases; GELA, 77.7%; and uPA, 64.7%. A significant correlation (P < .05) was found between high (more than 10%) ST3 expression and a younger age, lymph node involvement, poor nuclear grade, ductal histology, aneuploidy, and HSP-27 expression. High GELA expression was significantly associated with c-erbB2, ductal histology, and HSP-27 expression. High uPA expression correlated with poor nuclear grade, ductal histology, lack of estrogen and progesterone receptors, and p53 protein accumulation. High level of expression of all three proteases correlated significantly with each other and with cathepsin D expression by reactive stromal cells. By univariate analysis, both ST3 and uPA expression significantly predicted a shorter recurrence-free survival (ST3, P = .0199; uPA, P = .0269). By multivariate analyses, the prognostic significance was lost, most particularly at longer term. This study adds support to the concept that protease expression by reactive stromal cells is related to cancer cell characteristics but that their contribution to cancer progression is marginal.
 ...
PMID:Prognostic significance of stromelysin 3, gelatinase A, and urokinase expression in breast cancer. 974 15

Effects of all-trans retinoic acid (RA) on the net enzymatic activity of secreted, extracellular urokinase-type plasminogen activator (u-PA) in DU-145 human prostatic carcinoma cells were examined to assess the potential use of retinoids in human prostate cancer prevention and treatment. u-PA is associated with tumor progression involving invasion and metastasis. Based on a chromogenic substrate assay, results show that DU-145 cells secrete five times more u-PA than normal human prostatic epithelium. DU-145 cells were treated with 0.1 to 10 micrometer RA for 48 h. This short treatment of cells with RA did not inhibit growth. After a 48-h treatment of cultures with RA, serum-free conditioned medium was analyzed for u-PA activity by SDS-PAGE zymography. Two major bands of u-PA with Mr of approximately 54,000 (high molecular weight u-PA) and approximately 33,000 (low molecular weight u-PA) were detected. Plasminogen-dependent catalytic activity of these bands could be specifically inhibited with antibody to u-PA, confirming that these bands represent u-PA. A 48-h treatment with 1.0 micrometer RA reduced u-PA activity in conditioned medium to 51.6% of control. A 50% reduction in free u-PA antigen level, as compared to control, was further demonstrated at 1.0 micrometer RA by Western blot analysis and densitometry. These results show that RA can decrease the net extracellular urokinase activity produced by prostatic carcinoma cells. It is proposed that these effects of RA may have important implications not only in the chemoprevention of prostate cancer, by inhibition of promotion of prostatic intraepithelial neoplasia to invasive carcinoma, but also in tumor progression during invasion and metastasis, by decreasing extracellular matrix degradation, as shown in our accompanying article (M. M. Webber and A. Waghray, Clin. Cancer Res., 1: 755-761, 1995).
 ...
PMID:Retinoic acid modulates extracellular urokinase-type plasminogen activator activity in DU-145 human prostatic carcinoma cells. 981 41

Colony stimulating factor (CSF-1) and its receptor (CSF-1R, product of c-fms proto-oncogene) were initially implicated as essential for normal monocyte development as well as for trophoblastic implantation. However, recent findings have suggested that CSF-1 and CSF-1R might have additional roles in mammary gland development during pregnancy and lactation. Studies with osteopetrotic (op-/op-) mice, which bear a specific mutation that inactivates the CSF-1 gene, demonstrated that op-/op- mothers are incapable of normal milk production due to the incomplete development of their mammary glands during pregnancy. Also, significant increases in the levels of CSF-1 and CSF-1R proteins are observed in the epithelial cells of mammary gland during pregnancy and lactation. In vitro studies investigating the effect of the three major lactogenic hormones (prolactin, insulin, and glucocorticoids) on the expression of CSF-1 and CSF-1R have demonstrated that expression of CSF-1 can be regulated by prolactin and insulin whereas CSF-1R expression is regulated by glucocorticoids. This apparent role for CSF-1/CSF-1R in normal mammary gland development is very intriguing because this receptor/ligand pair has also been found to be important in the biology of breast cancer, where they regulate tumor cell invasion by a urokinase-dependent mechanism. This review aims to summarize recent findings on the role of CSF-1 and its receptor in normal and neoplastic mammary development which may elucidate potential relationships of growth factor-induced biological changes in the breast during pregnancy and tumor progression.
 ...
PMID:The role of CSF-1 in normal and neoplastic breast physiology. 989 62

Proteolytic degradation of the extracellular matrix plays a crucial role in both cancer invasion and non-neoplastic tissue remodeling processes. In human cancers the components of matrix degrading protease systems (uPA, uPAR, PAI-1 and MMPs) can be expressed by either the non-neoplastic stromal cells, the cancer cells or both. Studies of the prognostic impact of these components in human cancer and the effect of targeted gene inactivation on cancer metastasis in mice support the assumption that proteases promote cancer progression, independent of whether they are expressed by cancer cells or stromal cells. The pattern of expression of components of protease systems is usually very similar in different cases of the same type of cancer, while it varies between different types of cancer. There are intriguing similarities between the cellular expression pattern of components of protease systems seen in cancer invasion and in certain types of non-neoplastic tissue remodeling. We propose that cancer invasion can be viewed as tissue remodeling gone out of control. The stromal cell involvement in cancer invasion represents a new paradigm with important implications for cancer pathophysiology and cancer therapy.
 ...
PMID:Cancer invasion and tissue remodeling--cooperation of protease systems and cell types. 1019 Feb 88

Acquisition of invasive/metastatic potential through protease expression is an essential event in tumor progression. Urokinase-type plasminogen activator (uPA) is often expressed in human tumors including astrocytic tumors. To elucidate the possible regulation mechanism of uPA gene expression in astrocytic tumors, quantitative RT-PCR was performed to monitor the gene expression of uPA and the transcription factor Ets-1. Expression of uPA and Ets-1 genes was up-regulated in astrocytic tumors, but was not detected in normal brain. Expression levels of uPA correlated with those of Ets-1, and also with the degree of malignancy of the tumors. Glioma cell lines U251, U87, and T98G also expressed both uPA and Ets-1 genes. Expression of a dominant negative mutant of Ets-1, which competitively inhibits Ets-1 function, abolished uPA expression in U251 cells. Parental U251 cells showed invasive growth in 3-dimensional collagen gel, however, cells expressing dominant negative Ets-1 failed to grow invasively in the collagen gel. Treatment of U251 cells with the uPA inhibitor aprotinin also inhibited spreading of cells into collagen gel. These results suggest that Ets-1 plays an essential role in regulation of uPA gene expression, which in turn contributes to the invasive growth of astrocytic tumors.
 ...
PMID:Ets-1 positively regulates expression of urokinase-type plasminogen activator (uPA) and invasiveness of astrocytic tumors. 1021 28

Hepatocyte growth factor/scatter factor (HGF/SF) is a pleiotropic effector inducing invasion and metastasis of tumor cells that express the Met tyrosine kinase receptor. One of the effectors of HGF/SF is the urokinase-type plasminogen activator, a serine protease that facilitates tumor progression and metastasis by controlling the synthesis of the extracellular matrix degrading plasmin. Stimulation of NIH 3T3 cells that were stably transfected with the human Met receptor (NIH 3T3-Methum) with HGF/SF induced a trans-activation of the urokinase promoter and urokinase secretion. Induction of the urokinase promoter by HGF/SF via the Met receptor was blocked by co-expression of a dominant-negative Grb2 and Sos1 expression construct. Further, the expression of the catalytically inactive mutants of Ha-Ras, RhoA, c-Raf, and Erk2 or addition of the Mek1-specific inhibitor PD 098059 abrogated the stimulation of the urokinase promoter by HGF/SF. A sequence residing between -2109 and -1870 base pairs (bp) was critical for stimulation of the urokinase gene by HGF/SF. Mobility shift assays with oligonucleotides spanning an AP-1 site at -1880 bp or a combined PEA3/AP-1 site at -1967 bp showed binding of nuclear factors from NIH 3T3-Methum cells. Expression of an expression plasmid that inhibits DNA binding of AP-1 proteins (A-Fos) abrogated inducible and basal activation of the urokinase promoter. Nuclear extract from unstimulated NIH 3T3-Methum cells contained more JunD and showed a stronger JunD supershift with the AP-1 oligonucleotides, compared with HGF/SF-stimulated cells. Consistent with the levels of JunD expression being functionally important for basal expression of the urokinase promoter, we found that overexpression of wild type JunD inhibited the induction of the urokinase promoter by HGF/SF. These data suggest that the induction of urokinase by HGF/SF is regulated by a Grb2/Sos1/Ha-Ras/c-Raf/RhoA/Mek1/Erk2/c-++ +Jun-dependent mitogen-activated protein kinase pathway.
 ...
PMID:Activation mechanisms of the urokinase-type plasminogen activator promoter by hepatocyte growth factor/scatter factor. 1034 97

Fibroblast growth factor 7 (FGF7/KGF) is synthesized exclusively by fibroblasts in normal tissues; it acts as a potent mitogen on epithelial cells, through interaction with the FGF7-specific receptor FGFR2/IIIb. To examine the importance of this growth factor both to prostate physiology and to prostate-cancer progression, we have tested the exogenous effect of FGF7. Thus, by mimicking the paracrine pathway (on proliferation, growth in soft agar and invasion) on the human prostatic epithelial cell line PNT1A positively checked for FGFR2/IIIb expression, FGF7 significantly enhanced cell proliferation at an optimal concentration of 7.5 x 10(-11) M, but no significant invasion or growth in soft agar were observed. To confirm FGF7 properties on human prostatic epithelial cells, we constitutively expressed FGF7 by transfecting PNT1A cells with FGF7-cDNA. The FGF7-transfected clones, PNT1A/ FGF7-T5 and PNT1A/FGF7-T6, were stable and expressed FGF7. Analysis of the FGF7-autocrine loop on the non-tumorigenic epithelial cells PNT1A showed acquired invasive potential in in vitro extracellular-matrix migration assays, specifically inhibited by an FGF7-neutralizing antibody, and over-expressed factors implicated in the migration process: the metalloproteinase MMP-1 and the plasminogen activator uPA. Taken together, these results demonstrate a role for FGF7 in triggering invasion of human prostatic epithelial cells. Furthermore, these FGF7-transfected clones exhibited functional and physiological differences from the original PNT1A cell line: anchorage-independent growth, growth in serum-free media and increased proliferation. These data confirm the oncogenic function of FGF7 in prostate progression potentially acting through paracrine and/or autocrine regulatory pathways.
 ...
PMID:FGF7/KGF triggers cell transformation and invasion on immortalised human prostatic epithelial PNT1A cells. 1038 58

For tumor progression, a cascade of linked sequential biological events is essential. We tried to test whether biological therapy can modulate specific biological phenotypes and increase the anti-tumor effect when combined with chemotherapy. Five human gastric cancer cell lines (YCC-1, YCC-2, YCC-3, YCC-7, AGS) were used in these studies. Pentosan polysulfate (PPS) as a heparin-binding growth factor inhibitor, Tranexamic acid as a plasmin inhibitor, Lovastatin as an adhesion inhibitor and Adriamycin as a chemotherapeutic agent were selected. The effects of each drug on colony formation and tumor cell proliferation were evaluated by soft agar assay and cell proliferation assay, respectively to test direct anti-tumor effect. The expression of uPA, PAI-1 was determined by ELISA, while MMPs activity was evaluated by zymography. PPS suppressed the colony-forming activity as much as Adriamycin did, but it showed only cytostatic effects in cell proliferation assay. Migration capacity using Boyden chamber assay was more closely correlated with adhesive capacity than uPA or MMP-2 expression. The motility inhibitory effect of Tranexamic acid was observed in the YCC-7 cell line, which expressed all the required biological phenotypes for migration. In AGS, with high cell motility and adhesiveness, the adhesion was inhibited by Lovastatin and most of the inhibitory effect was recovered by Mevalonate. When PPS was combined with Adriamycin on the Adriamycin-resistant, midkine (MK) gene expressing YCC-7 cell line, the growth inhibition rate increased up to 84%, while that for a single treatment of PPS or Adriamycin was 40% and 22%, respectively (p=0.001). When we combined Tranexamic acid and Adriamycin, we observed the synergistic effect in YCC-3 and YCC-7, while no combined effect was found in YCC-1. The combination of Lovastatin and Adriamycin did not show any combined effects in any of the cell lines. In conclusion, a synergistic anti-proliferative effect (chemo-sensitization) with combined chemo-biotherapy was found in cancer cells with specific biological target, MK. The anti-motility effect was the greatest when the gastric cancer cells expressed all the specific biological phenotypes.
 ...
PMID:Modulation of biological phenotypes for tumor growth and metastasis by target-specific biological inhibitors in gastric cancer. 1040 90

During the complex multistep process of tumor progression, prostate cancer is initiated as an androgen-sensitive, nonmetastatic cancer, followed by a gradual transition into a highly metastatic and androgen-insensitive variety that lacks the expression of functional androgen receptors (AR). Urokinase (uPA), a member of the serine protease family, has been implicated in the progression of various human malignancies, including prostate cancer. Although uPA production is regulated by various growth factors and cytokines, the role of sex steroids (androgens) in regulating uPA gene expression in prostate cancer is poorly understood. In the current study, we have examined the role of androgens in regulating uPA production and the invasive capacity of the androgen insensitive PC-3 cells transfected with the full-length human AR complementary DNA (PC-3T). Restoration of androgen responsiveness in PC-3T cells caused a marked decrease in cell doubling time. Treatment of PC-3T cells with dihydroxytestosterone (DHT) caused a dose-dependent decrease in uPA messenger RNA and protein production, resulting in their decreased ability to invade through the Matrigel. Nuclear runoff assays revealed that these effects were attributable to the ability of DHT to inhibit uPA gene transcription. AR antagonist flutamide (Flu) reversed the effect of DHT on proliferation and invasion of PC-3T cells. Both control (PC-3) and experimental (PC-3T) cells were injected into the right flank of male BALB/c nu/nu mice. Control animals developed palpable tumors and microscopic tumor metastases at lymph nodes, lungs, and liver at 6-week posttumor cell inoculation. In contrast to this, because of androgen sensitivity of PC-3T cells, palpable tumors were observed only at week 12, with occasional tumor metastases in lungs. Furthermore, inoculation of PC-3T cells into surgically castrated host animals resulted in the development of tumors at a much earlier time (week 10) and a high incidence of metastases, compared with regular animals receiving PC-3T cells. Collectively, these results demonstrate the ability of androgen to regulate uPA production, which may directly effect prostate cancer growth, invasion, and metastasis in vitro and in vivo.
 ...
PMID:Regulation of urokinase production by androgens in human prostate cancer cells: effect on tumor growth and metastases in vivo. 1046 76


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>