Differences in microbial and archaeal composition between mucosal samples from healthy and disease tissues were observed in tubular adenoma and adenocarcinoma. In addition, microbiota from mucosal samples represented the underlying dysbiosis, whereas fecal samples seem not to be appropriate to detect shifts in microbial composition. CRC risk is influenced by microbial composition, showing differences according to disease progression step and tumor severity.

Objective-Low-density lipoprotein (LDL) receptor-related protein (LRP1) mediates the internalization of aggregated LDL (agLDL)-LDL trapped in the arterial intima bound to proteoglycans-into human vascular smooth muscle cells (VSMC). LRP1-mediated agLDL uptake induces high-intracellular cholesteryl ester (CE) accumulation. The aim of this study was to characterize the mechanism of agLDL internalization in human VSMC. Methods and Results-The lipidic component of LDL was labeled with [ 3 H] and the apolipoprotein component with [ 125 I]. We found that 90% of intracellular CE derived from agLDL uptake was not associated with apoB100 degradation but was selectively taken up from agLDL. The inhibition of LRP1 expression by small interfering RNA treatment led to a decrease of 800.05% in agLDL-CE selective uptake. AgLDL induced intracellular CE accumulation without a concomitant CE synthesis. Cytosolic and cytoskeletal proteins were not required for CE transport. Electron and confocal microscopy experiments indicate that CE derived from agLDL accumulated in adipophilin-stained lipid droplets that were not removable by high-density lipoprotein. Conclusions-Taken together, these results demonstrate that LRP1 mediates the selective uptake of CE from agLDL and that CE derived from agLDL is not intracellularly processed but stored in lipid droplets in human VSMC. (Arterioscler Thromb Vasc Biol. 2006;26:117-123.) Key Words: LRP1 selective uptake cholesteryl ester adipophilin aggregated LDL O ne of the main events in the atherogenic process is the accumulation of lipids, mainly cholesteryl esters (CEs), in the subendothelial space of the arterial wall. 1-3 Macro-phages become foam cells through uptake of diversely modified low-density lipoprotein (LDL), whereas aggrega-tion of LDL (agLDL) seems to be a key condition for lipid accumulation in vascular smooth muscle cells (VSMCs). 4,5 We have demonstrated previously that the pattern of agLDL internalization differs from that of native LDL (nLDL) in human VSMC. Endocytosed nLDL were found in bright vesicles that were homogenously distributed in the perinu-clear space, leading to an unstained cytoplasm surrounding the fluorescent vesicles. In contrast, agLDLs were found in bigger and more diffuse structures distributed throughout the cytoplasm. 5 Contrarily to nLDL, agLDL was shown to be a strong inducer of intracellular CE accumulation in human VSMC. 5-8 These findings are related to differences in the internalization mechanisms; whereas nLDL is taken up by the endocytic LDL receptor (LDLr), which is downregulated by intracellular cholesterol, agLDL is taken up through LDLr-related protein (LRP1). 6,7 Uptake of agLDL through LRP1 allows high-intracellular CE accumulation not only because of its high capacity to bind and internalize agLDL but also because of its transcriptional upregulation by intracellular cholesterol. 8 LRP1 collaborates with heparan sulfate proteo-glycans (HS-PGs) to mediate the internalization of certain ligands. 9,10 However, in human VSMC, we have demonstrat...

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Objective-Hypoxia is considered a key factor in the progression of atherosclerotic lesions. Low-density lipoprotein receptor-related protein (LRP1) plays a pivotal role in the vasculature. The aim of this study was to investigate the effect of hypoxia on LRP1 expression and function in vascular smooth muscle cells (VSMC) and the role of hypoxia-inducible factor-␣ (HIF-1␣). Methods and Results-Real-time polymerase chain reaction and Western blot analysis demonstrated that hypoxia (1% O 2 ) time-dependently induced LRP1 mRNA (maximum levels at 1 to 2 hours) and protein expression (maximum levels at 12 to 24 hours). The delayed hypoxic upregulation of LRP1 protein versus mRNA may be explained by the long half-life of LRP1 protein. Luciferase assays demonstrated that hypoxia and HIF-1␣ overaccumulation induced LRP1 promoter activity and that 2 consensus hypoxia response element sites located at Ϫ1072/Ϫ1069 and Ϫ695/Ϫ692 participate in the induction. Chromatin immunoprecipitation showed the in vivo binding of HIF-1␣ to LRP1 promoter in hypoxic VSMC. Hypoxia effects on LRP1 protein expression were functionally translated into an increased cholesteryl ester (CE) accumulation from aggregated low-density lipoprotein (agLDL) uptake. The blockade of HIF-1␣ expression inhibited the upregulatory effect of hypoxia on LRP1 expression and agLDL-derived intracellular CE overaccumulation, suggesting that both LRP1 overexpression and CE overaccumulation in hypoxic vascular cells are dependent on HIF-1␣. Immunohistochemical analysis showed the colocalization of LRP1 and HIF-1␣ in vascular cells of human advanced atherosclerotic plaques. H ypoxia plays a pivotal role in the pathophysiology of cancer, myocardial infarction, and atherosclerosis. Arterial wall thickness associated with atherosclerotic plaque progression reduces the oxygen supply in certain areas of the vascular intima. 1,2 Hypoxia is present in human advanced atherosclerotic lesions and correlates with the presence of angiogenesis and thrombus. 3,4 Most of the cells in hypoxic areas of atherosclerotic plaques respond by altering the expression of genes involved in vasculogenesis, angiogenesis, inflammation, and lipid deposition. [5][6][7][8][9][10][11] These genes are activated through hypoxia-inducible factor-1 complex (HIF-1). The HIF-1␣ subunit is subjected to quick oxygendependent proteasomal degradation through hydroxylation of proline residues by hydroxylases. [12][13][14] Under low oxygen tensions, HIF-1␣ accumulates and heterodimerizes with the constitutively expressed beta subunit, allowing the HIF-1 complex to bind to hypoxia response element (HRE) sequences in target promoters. 15 It has been reported that HIF-1␣ accumulation in macrophages promotes foam cell formation and atherosclerosis. 16 In experimental models of hypercholesterolemia and hypertension, HIF-1␣ is also associated with vascular smooth muscle cells (VSMC). 17 30 -32 It is unknown whether hypoxia may modulate LRP1 expression in human atherosclerotic plaques and, if so, which transcription ...

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Cancer stem cells (CSC) contribute to disease progression and treatment failure in prostate cancer because of their intrinsic resistance to current therapies. The transcription factors NF-kB and STAT3 are frequently activated in advanced prostate cancer and sustain expansion of prostate CSCs. EC-70124 is a novel chimeric indolocarbazole compound generated by metabolic engineering of the biosynthetic pathways of glycosylated indolocarbazoles, such as staurosporine and rebeccamycin. In vitro kinome analyses revealed that EC-70124 acted as a multikinase inhibitor with potent activity against IKKb and JAK2. In this study, we show that EC-70124 blocked concomitantly NF-kB and STAT3 in prostate cancer cells and particularly prostate CSCs, which exhibited overactivation of these transcription factors. Phosphorylation of IkB and STAT3 (Tyr705), the immediate targets of IKKb and JAK2, respectively, was rapidly inhibited in vitro by EC-70124 at concentrations that were well below plasma levels in mice. Furthermore, the drug blocked activation of NF-kB and STAT3 reporters and suppressed transcription of their target genes. Treatment with EC-70124 impaired proliferation and colony formation in vitro and delayed development of prostate tumor xenografts. Notably, EC-70124 had profound effects on the prostate CSC subpopulation both in vitro and in vivo. Thus, EC-70124 is a potent inhibitor of the NF-kB and STAT3 signaling pathways and blocked tumor growth and maintenance of prostate CSCs. EC-70124 may provide the basis for developing new therapeutic strategies that combine agents directed to the CSC component and the bulk tumor cell population for treatment of advanced prostate cancer. Mol Cancer Ther; 15(5); 806-18. Ó2016 AACR.

Background: LRP1 plays a major role in foam cell formation from human vascular smooth muscle cells (hVSMCs). Results: Antibodies generated against the C-terminal half of cluster II CR9 domain (Gly 1127 -Cys 1140 ) efficiently prevented hVSMC foam cell formation. Conclusion: CR9 is key for AgLDL binding and internalization. Significance: Our results open new avenues for treating vascular lipid deposition in atherosclerosis.