Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The enzyme, thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor (PD-ECGF), which acts as a potent angiogenic factor. The present study immunohistochemically examined the expression of dThdPase in human colorectal mucosa, adenomas and carcinomas, as well as six cultured colorectal carcinoma cell lines, in terms of intratumoral microvessel density (IMVD) and P53 expression. Thymidine phosphorylase was observed in lymphocytes, fibroblasts and macrophages, as well as smooth muscle cells and Schwann cells in the peripheral nerve fibers. The dThdPase-positive stromal cells apparently outnumbered the normal epithelial cells, adenoma and carcinoma cells with dThdPase. Weak but obvious cytoplasmic immunoreactivity was noted in a few normal colonic epithelia, predominantly the upper surface area, while a few adenoma cells showed weak nuclear immunostaining for dThdPase in six (24%) of the 25 colonic adenomas. Expression of dThdPase was noted in 33 (73.3%) of the 45 Dukes A and B, 14 (51.9%) of the 27 Dukes C and 14 (56.0%) of the 25 Dukes D carcinomas. The mean IMVD was 84.0 +/- 26.2 in the 36 dThdPase-negative carcinomas and 97.9 +/- 31.6 in the 61 dThdPase-positive carcinomas, the value being significantly higher in the latter group (P < 0.05). The frequency of dThdPase expression was significantly lower in the P53-negative carcinomas than in the positive carcinomas (P < 0.05). Western blot analysis showed the highest expression of dThdPase in LoVo carrying the wild-type p53 gene, followed by Colo201, Colo320, DLD-11 and WiDr carrying the mutated gene. These results indicate that: (i) the main source of dThdPase is stromal cells, including lymphocytes and macrophages in both colorectal normal and carcinoma tissues; (ii) dThdPase may take part in the induction of intratumoral microvessels, regardless of tumor stage; and (iii) expression might be modulated by not only P53 but also other molecules.
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PMID:Thymidine phosphorylase expression in human colorectal mucosa, adenoma and carcinoma: role of p53 expression. 1046 91

The aim of this study was to investigate the expression of platelet-derived endothelial growth factor (PD-ECGF) in human gallbladder carcinomas to elucidate its role in angiogenesis and tumour progression. To this end, 56 archival surgical specimens of gallbladder lesions were examined for PD-ECGF/thymidine phosphorylase (TP) expression by immunohistochemistry and the PD-ECGF/TP protein level was assessed in five fresh specimens of gallbladder carcinoma by enzyme-linked immunosorbent assay (ELISA). Hyperplastic epithelial cells and adenoma cells showed no or faint staining with PD-ECGF/TP. Out of 43 gallbladder carcinomas, 27 (63%) showed moderate to strong immunoreactivity in the cytoplasm and nuclei of the tumour cells. PD-ECGF/TP immunoreactivity in stromal infiltrating cells was detected in 43% (3/7) hyperplasias, 17% (1/6) adenomas and 86% (37/43) carcinomas. PD-ECGF/TP protein levels in carcinoma tissues were higher than those in corresponding normal mucosa. PD-ECGF/TP expression did not correlate with angiogenesis, but significantly correlated with depth of invasion, lymph node metastasis, and tumour stage. These results overall suggest that PD-ECGF/TP produced by both cancer cells and infiltrating cells is associated with tumour progression in human gallbladder carcinoma.
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PMID:Expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase in human gallbladder lesions. 1074 Dec 86

Several studies have supported the hypothesis that adrenocortical tumor formation is the result of a multistep process. The angiogenic switch has been proposed to be a key step in tumor progression from adenoma to carcinoma. In this study we measured the cytosolic concentrations of three proteins involved in angiogenesis [namely platelet-derived endothelial cell growth factor vascular endothelial cell growth factor A (VEGF-A), and thrombospondin-1 (TSP1)] in a series of 43 human sporadic adrenocortical tumors. The tumors were classified as adenomas (n = 18), transitional tumors (n = 12), or carcinomas (n = 13) according to the histological criteria defined by Weiss. Platelet-derived endothelial cell growth factor/thymidine phosphorylase levels were not significantly different among these three groups. One hundred percent of the adenomas and 73% of the transitional tumors showed VEGF-A concentrations under the threshold value of 107 ng/g protein, whereas 75% of the carcinomas had VEGF-A concentrations above this threshold value. Similarly, 89% of the adenomas showed TSP1 concentrations above the threshold value of 57 microg/g protein, whereas only 25% of the carcinomas and 33% of the transitional tumor samples did so. Insulin-like growth factor II overexpression, a common genetic alteration of adrenocortical carcinomas, was significantly correlated with higher VEGF-A and lower TSP1 concentrations. The tumors from the 6 patients with tumor recurrence after surgical ablation showed significantly higher VEGF-A values than the carcinomas and the transitional tumors from patients that did not relapse. Taken together, these data suggest that a decrease in TSP1 expression is an event that precedes an increase in VEGF-A expression during adrenocortical tumor progression. The population of premalignant tumors with low TSP1 and normal VEGF-A levels could represent a selective target for antiangiogenic therapies.
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PMID:Expression of the angiogenesis markers vascular endothelial growth factor-A, thrombospondin-1, and platelet-derived endothelial cell growth factor in human sporadic adrenocortical tumors: correlation with genotypic alterations. 1113 36

Details of concurrent expression of angiogenic growth factors (AGFs) and microvessel density (MVD) in human colorectal adenomas and carcinomas remain obscure. Eighty lesions, 20 each from colorectal adenoma, Tis, T1 and T2 cancers were evaluated immunohistochemically for basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), thymidine phosphorylase (dThdPase) and MVD. MVD (p = 0.0001) and bFGF expression (p = 0.0001) increased in the order of adenoma, Tis, T1 and T2 cancers. VEGF expression was same in adenomas and cancers while dThdPase was weak in adenomas but strongly expressed in invasive carcinomas ( > T1). MVD had positive correlation with tumour size in small (< or = 4 cm) colorectal cancers. Concurrent expression of AGFs was noticed in invasive carcinomas. bFGF seems to be the strongest among the three AGFs expressed during colorectal carcinogenesis and had a significant correlation with tumour MVD. Concurrent expression of multiple AGFs is a crucial step in the transition from non-invasive to invasive carcinoma.
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PMID:Concurrent expression of angiogenic growth factors and neovascularization during tumourigenesis in colorectal carcinoma patients. 1166 35