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)

Peroxisome proliferator-activated receptor gamma (PPAR gamma) immunohistochemical expression was analyzed in 75 human bladder tumor specimens, where the expression of some angiogenic factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived endothelial cell growth factor (PDECGF), and tumor progression markers, such as epidermal growth factor receptor (EGFr), p16, mutated p53, and normal pRB, were also analyzed. The results were then compared to the clinical and pathological characteristics of the disease. PPAR gamma was expressed more significantly in papillary tumors than in solid cancers, and its presence was associated with statistical significance to low incidence of tumor recurrence or progression. This significant association was observed also when PPAR gamma was expressed in the presence of PDECGF, which resulted, when considered alone, to an angiogenic factor typical of solid cancers and appeared related to poor prognosis. In the presence of bFGF, on the contrary, PPAR gamma expression no longer resulted to a significant association with low incidence of tumor recurrence or progression, suggesting a possible worsening role of this angiogenic factor, typical of papillary cancers, in its interaction with PPAR gamma.
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PMID:The role of peroxisome proliferator-activated receptor gamma in bladder cancer in relation to angiogenesis and progression. 1188 83

Angiogenesis is a multi-step process leading to the formation of new blood vessels from pre-existing vasculature and it is necessary for primary tumor growth, invasiveness and development of metastasis. Experimental and clinical data demonstrated that breast cancer is an angiogenesis-dependent disease and that the vascular endothelial growth factor (VEGF) family plays a key role it being a highly expressed and selective endothelial cell growth factor. Preclinical studies have shown that the angiogenic switch occurs early in the multistage process of breast cancer development. Targeting the molecular pathways involved in tumor progression by biologically-designed treatments is a new therapeutic paradigm aimed to reach cancer growth control. A number of possible therapeutic targets for antiangiogenic agents have been identified. Here we discuss the therapeutic approach based on inhibition of angiogenesis in the context of breast cancer with a focus on the early clinical studies on antiangiogenic agents in advanced disease.
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PMID:Antiangiogenic strategies, compounds, and early clinical results in breast cancer. 1501 71

The thrombospondins (TSPs) are a family of proteins that regulate tissue genesis and remodeling. In many tumors, down-regulation of TSPs accompanies activation of oncogenes or inactivation of tumor suppresser genes and appears to be a prerequisite for the aquisition of a pro-angiogenic phenotype. The normal suppression of angiogenesis by TSP-1 and -2 involves multiple mechanisms including direct interaction with vascular endothelial cell growth factor (VEGF), inhibition of matrix metalloproteinase 9 (MMP9) activation, inhibition of endothelial cell migration and induction of endothelial cell apoptosis. The importance of down-regulation of TSPs for tumor progression is further established by the fact that several different approaches that are designed to increase the levels of TSP-1 or -2 in tumor tissue inhibit tumor growth. These approaches include cell-based gene therapy, low dose chemotherapeutics and systemic delivery of recombinant proteins or synthetic peptides that include type 1 repeat (TSR) sequences. Initial studies indicate that these reagents, in combination with established approaches for the treatment of cancer, will offer more efficacious therapies.
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PMID:Tumor progression: the effects of thrombospondin-1 and -2. 1509 19

The role of platelets in tumor progression and metastasis has been recognized but the mechanism of their action remains unclear. Five human lung cancer cell lines (A549, CRL 2066, CRL 2062, HTB 183, HTB 177) and a murine Lewis lung carcinoma (LCC) cell line (for an in vivo model of metastasis) were used to investigate how platelet-derived microvesicles (PMV), which are circular fragments shed from the surface membranes of activated platelets, and exosomes released from platelet alpha-granules, could contribute to metastatic spread. We found that PMV transferred the platelet-derived integrin CD41 to most of the lung cancer cell lines tested and stimulated the phosphorylation of mitogen-activated protein kinase p42/44 and serine/threonine kinase as well as the expression of membrane type 1-matrix metalloproteinase (MT1-MMP). PMV chemoattracted 4 of the 5 cell lines, with the highly metastatic A549 cells exhibiting the strongest response. In A549 cells, PMV were shown to stimulate proliferation, upregulate cyclin D2 expression and increase trans-Matrigel chemoinvasion. Furthermore, in these cells, PMV stimulated mRNA expression for angiogenic factors such as MMP-9, vascular endothelial growth factor, interleukin-8 and hepatocyte growth factor, as well as adhesion to fibrinogen and human umbilical vein endothelial cells. Intravenous injection of murine PMV-covered LLC cells into syngeneic mice resulted in significantly more metastatic foci in their lungs and LLC cells in bone marrow than in control animals injected with LCC cells not covered with PMV. Based on these findings, we suggest that PMV play an important role in tumor progression/metastasis and angiogenesis in lung cancer.
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PMID:Microvesicles derived from activated platelets induce metastasis and angiogenesis in lung cancer. 1549 15

Platelets have long been suspected of having a role in cancer progression and metastasis that has largely been attributed to platelet-mediated enhancement of tumor cell survival, extravasation, and angiogenesis. A study in this issue of the JCI suggests that platelet-derived lysophosphatidic acid is coopted by aggressive breast and ovarian cancer cells as a tumor cell mitogen and promoter of osteolysis during bone metastasis.
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PMID:Platelets and metastasis revisited: a novel fatty link. 1559 96

The Ink4a/Arf tumor suppressor locus is widely inactivated in cancer but little is known about the tumor biology of its two products, p16(Ink4a) (p16) and Arf. Both the p16 and Arf promoters are methylated in a significant fraction of human colon carcinomas, implying a functional role. We have demonstrated previously that Ink4a/Arf-null colon tumors display increased growth and vascularity in C57Bl6 mice carrying the Min (multiple intestinal neoplasia) mutation. We present here an analysis in a mixed genetic background of Min colon tumors (N=215) in mice with or without selective deficiencies in p16 or Arf, respectively. Absence of Arf did not significantly alter tumor formation. In contrast, tumors in mice lacking p16 were moderately larger and redder. Histological analysis demonstrated that these tumors contained significantly more pockets of necrosis (p=0.02), a marker of carcinoma in situ; less apoptosis (p=0.02); and higher red blood cell density (p=0.02, 0.006 within vessels). Biochemical analyses demonstrated increased levels of vascular endothelial cell growth factor (VEGF, p<0.01). Exogenous p16 expression in human colon tumor cells in vitro inhibited VEGF production. These results suggest that p16 constrains colon tumor progression, in part through inhibiting angiogenic signaling.
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PMID:p16(Ink4a) inhibits histologic progression and angiogenic signaling in min colon tumors. 1632 87

An angiogenic factor, platelet-derived endothelial cell growth factor/thymidine phosphorylase (TP), stimulates the chemotaxis of endothelial cells and confers resistance to apoptosis induced by hypoxia. 2-Deoxy-d-ribose, a degradation product of thymidine generated by TP enzymatic activity, partially prevented hypoxia-induced apoptosis. 2-Deoxy-d-ribose inhibited hypoxia-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK) but not c-jun NH(2)-terminal kinase/stress-activated protein kinase in human leukemia HL-60 cells. 2-Deoxy-d-ribose also suppressed the levels of Bax attached to mitochondria under hypoxic conditions. SB203580, a specific inhibitor of the p38 MAPK, suppressed the hypoxia-induced apoptosis of HL-60 cells. These findings suggest that one of the molecular bases for resistance to hypoxia-induced apoptosis conferred by 2-deoxy-d-ribose is the inhibition of the p38 signaling pathway. The expression levels of TP are elevated in many malignant solid tumors and thus the 2-deoxy-d-ribose generated by TP in these tumors may play an important role in tumor progression by preventing hypoxia-induced apoptosis.
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PMID:2-Deoxy-D-ribose inhibits hypoxia-induced apoptosis by suppressing the phosphorylation of p38 MAPK. 1648 Sep 51

Recent studies emphasize the paramount significance of beta 3 integrin in cell adhesion and homing, which may be particularly relevant in cancer progression and metastasis. In contrast, the presence and potential role of beta 3 on human T cells is practically unknown. We show that T cells can express significant amounts of alpha-beta 3 integrin (CD41/CD61), and the expression of alpha(v)-beta 3 (CD51/CD61) remains very low. T-cell beta 3 integrin is probably transferred by platelet-derived microparticles.
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PMID:Beta 3 integrin expression on T cells from renal allograft recipients. 1650 41

The formation of new blood vessels in endometrial cancer tissue is a main process, which leads to tumor progression, and is connected with tumor expansion and invasiveness. The aim of the study was evaluation of thymidine phosphorylase protein (TP) expression in human endometrial cancer cells by immunohistochemistry and comparison obtained data with intensity of angiogenesis process and clinicopathological factors as FIGO stage of disease and histopathologic grade. Endometrial cancer specimens were obtained from 55 postmenopausal patients (aged 52 to 74 years) underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy. None of patients received preoperative pelvic irradiation. Histopathological typing and grading of the endometrial tumors (G-1, G-2, G-3) as well as myometrial invasion (<1/2, >1/2) were assessed using standard criteria, on hematoxylin-eosin sections. At the surgery, FIGO clinical stage of disease was determined. Thymidine phosphorylase overexpression was observed in 23 of 55 (41.8%) cases of endometrial cancer. Although we found no statistically significant differences in TP expression between histopathologic grades, particular FIGO stages showed a significant trend of increase TP tumor overexpression. Thymidine phosphorylase overexpression cases demonstrate higher intensity of angiogenesis in comparison to negative samples and results are statistically significant for t-test (p<0.0001). The most intensive new blood vessel formation was observed in G-2 of tumor differentiation grade (p=0.013 for ANOVA test) Mean angiogenic points density (APD) values in cases of G-1 histopathologic grade reached 135.7; values of G-2 and G-3 grades reached 213.8 and 162.8, respectively. Mean intensity of angiogenesis in the first FIGO stage of disease reached 160.0 APD, in stage II 205.6 APD, and in the third 286.9, respectively. Angiogenesis was more intensive in cases of advanced tumors - analysis of variance (ANOVA) confirmed statistically significant differences in APD values between FIGO stage groups (p=0.0007). In conclusion, thymidine phosphorylase expression correlates with increased microvessel density in endometrial cancer. The intensity of angiogenesis process increases according to FIGO stage of disease, which is connected with progressing of cancer disease. Thymidine phosphorylase can play an important role in endometrial cancer progression and could offer additional information about advance of disease.
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PMID:Evaluation of tumor angiogenesis and thymidine phosphorylase tissue expression in patients with endometrial cancer. 1665 95

Platelets, essentially non-nucleated blood cells, are highly reactive components of the circulatory system. They have long been consigned solely to a role in thrombosis and hemostasis. Platelets release platelet-derived microvesicles (PMV), also known as platelet-derived microparticles (PMP). They are important but still under-appreciated mediators of intracellular cross-talk between platelets and other cells and modulate their function. They are formed after stimulation of platelets by an agonist, such as thrombin, collagen, and many others. Platelets can carry biological mediators; they can modulate immune responses and inflammatory events. Microparticles can be released from activated platelets and leukocytes in inflammatory events, but in atherosclerosis they can be released from apoptotic endothelial cells, lymphocytes, and monocytes. The markers of innate immunity expressed by platelets are Toll-like receptors (TLRs). The role of platelets in tumor progression and metastasis has been recognized, but the mechanism of their action remains still unclear.
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PMID:[Platelet-mediated regulation of immunity]. 1670 26


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