Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P39060 (endostatin)
 2,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Endostatin inhibits angiogenesis and tumor growth in mice. The role of its endogenous precursor collagen XVIII in human cancer is unknown. In normal tissues, two variants of collagen XVIII, namely, the short and long forms regulate tissue specificity, the long form being almost exclusively expressed by hepatocytes in the liver. We analyzed RNA arrays from 57 hepatocellular carcinomas (HCCs) with common and variant-specific probes and investigated the relationships between collagen XVIII expression and angiogenesis by measuring the CD34-positive microvessel density. Low collagen XVIII expression by tumor hepatocytes was associated with large tumor size (r, -0.63; P < 0.001) and replacement of trabeculae with pseudoglandular-solid architecture (chi2, 28; P < 0.001), which indicate tumor progression. Tumors expressing the highest collagen XVIII levels were smaller and had lower microvessel density (P = 0.01) than those expressing moderate levels; and HCCs with the lowest collagen XVIII levels approached a plateau of microvessel density, which indicated that a decrease in collagen XVIII expression is associated with angiogenesis in primary liver cancer. HCCs recurring within 2 years of resection showed 2.2-fold lower collagen XVIII mRNA than nonrecurring ones (P = 0.02). The findings relied on the hepatocyte-specific long form. Thus, the endogenous expression of the endostatin precursor decreases along with tumor progression in HCCs.
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PMID:Tumor progression is associated with a significant decrease in the expression of the endostatin precursor collagen XVIII in human hepatocellular carcinomas. 1119 95

Tumor progression is dependent in large part on angiogenesis and angiogenesis inhibitors have repeatedly been shown to inhibit tumor growth. The present study sought to determine whether the oral squamous carcinoma cells expressed and produced collagen XVIII, a known precursor of endostatin. Four established cell lines of oral squamous cell carcinoma (SCC) were employed for these studies. Quantitative Real-Time RT-PCR was used to assess the expression of collagen XVIII and CBP2/Hsp47, an ostensible chaperone for fibrillar and basement membrane collagens. Real-Time PCR assessment of collagen XVIII with primers selected to the common region of collagen XVIII revealed variable expression among cell lines of oral SCC. Conversely, the long form of collagen XVIII revealed no products. Comparatively, the lowest level of expression of CBP2/Hsp47 was observed in SCC4 that also had the lowest level of collagen XVIII. However, there was no direct relationship between the levels of CBP2/Hsp47 and collagen XVIII expression across the four cell lines. Treatment of SCC cells with CBP2/Hsp47 antisense phosphorothioate oligonucleotides modulated the production of collagen XVIII but not its expression. These findings imply that CBP2/Hsp47 may play a role in tumor progression by mediating the endogenous processing of collagen XVIII in tumor cells.
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PMID:The production of the endostatin precursor collagen XVIII in head and neck carcinomas is modulated by CBP2/Hsp47. 1217 73

Heparan sulfate proteoglycans (HSPGs) may play a role in the formation and persistence of senile plaques and neurofibrillary tangles in Alzheimer's disease brains. Recently, it has been demonstrated that the human extracellular matrix-associated molecule collagen XVIII is the first collagen carrying heparan sulfate side-chains. Two variants of collagen XVIII with both different signal peptides and N-terminal domains have been described and are referred to as the short and long form. To investigate the distribution of these variants we performed an immunohistochemical analysis by using specific well-characterized polyclonal antibodies. Anti-long huXVIII, a polyclonal antibody directed against the long variant of collagen XVIII, weakly stained large cortical and leptomeningeal vessels, whereas small cortical vessels remained unstained. Interestingly, all amyloid-laden vessels and classic senile plaques were strongly stained. Anti-all huXVIII, a polyclonal antibody directed against an epitope common to both collagen XVIII variants, intensely stained all types of cerebral blood vessels, cerebral amyloid angiopathy-affected vessels and classic senile plaques. Collagen XVIII expression was absent in neurofibrillary tangles. We conclude that collagen XVIII is a novel heparan sulfate proteoglycan associated with vascular A beta and classic senile plaques and that at least the long form of collagen XVIII accumulates in amyloid-laden vessels and classic senile plaques.
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PMID:Collagen XVIII: a novel heparan sulfate proteoglycan associated with vascular amyloid depositions and senile plaques in Alzheimer's disease brains. 1240 31