ABSTRACT
miRNAs have emerged as master regulators of cancer-related events. miRNA dysregulation also occurs in Kaposi sarcoma (KS). Exploring the roles of KS-associated miRNAs should help to identify novel angiogenesis and lymphangiogenesis pathways. In the present study, we show that Kaposi sarcoma-associated herpesvirus (KSHV), the etiological agent of KS, induces global miRNA changes in lymphatic endothelial cells (LECs). Specifically, the miR-221/miR-222 cluster is down-regulated, whereas miR-31 is up-regulated. Both latent nuclear antigen (LANA) and Kaposin B repress the expression of the miR-221/miR-222 cluster, which results in an increase of endothelial cell (EC) migration. In contrast, miR-31 stimulates EC migration, so depletion of miR-31 in KSHV-transformed ECs reduces cell motility. Analysis of the putative miRNA targets among KSHV-affected genes showed that ETS2 and ETS1 are the downstream targets of miR-221 and miR-222, respectively. FAT4 is one of the direct targets of miR-31. Overexpression of ETS1 or ETS2 alone is sufficient to induce EC migration, whereas a reduction in FAT4 enhances EC motility. Our results show that KSHV regulates multiple miRNA-mRNA networks to enhance EC motility, which eventually contributes to KS progression by promoting the spread of malignant KS progenitor cells. Targeting KSHV-regulated miRNAs or genes might allow the development of novel therapeutic strategies that induce angiogenesis or allow the treatment of pathogenic (lymph)angiogenesis.
Subject(s)
Cell Movement , Endothelium, Lymphatic/pathology , Endothelium, Vascular/pathology , Gene Regulatory Networks , Herpesvirus 8, Human/pathogenicity , MicroRNAs/genetics , Sarcoma, Kaposi/genetics , Sarcoma, Kaposi/pathology , Antigens, Viral/genetics , Antigens, Viral/metabolism , Biomarkers/metabolism , Blotting, Western , Cadherins/genetics , Cadherins/metabolism , Cells, Cultured , Endothelium, Lymphatic/metabolism , Endothelium, Lymphatic/virology , Endothelium, Vascular/metabolism , Endothelium, Vascular/virology , Fluorescent Antibody Technique , Gene Expression Profiling , Humans , Immunoenzyme Techniques , Luciferases/metabolism , Nuclear Proteins/antagonists & inhibitors , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Oligonucleotide Array Sequence Analysis , Proto-Oncogene Protein c-ets-1/genetics , Proto-Oncogene Protein c-ets-1/metabolism , Proto-Oncogene Protein c-ets-2/genetics , Proto-Oncogene Protein c-ets-2/metabolism , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sarcoma, Kaposi/virology , Stem Cells , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolismABSTRACT
BACKGROUND: It has been recognized cancer cells acquire characters reminiscent of those of normal stem cells, and the degree of stem cell gene expression correlates with patient prognosis. Lgr5(+) or CD133(+) epithelial stem cells (EpiSCs) have recently been identified and these cells are susceptible to neoplastic transformation. It is unclear, however, whether genes enriched in EpiSCs also contribute in tumor malignancy. Endometrial endometrioid carcinoma (EEC) is a dominant type of the endometrial cancers and is still among the most common female cancers. Clinically endometrial carcinoma is classified into 4 FIGO stages by the degree of tumor invasion and metastasis, and the survival rate is low in patients with higher stages of tumors. Identifying genes shared between advanced tumors and stem cells will not only unmask the mechanisms of tumor malignancy but also provide novel therapeutic targets. RESULTS: To identify EpiSC genes in late (stages III-IV) EECs, a molecular signature distinguishing early (stages I-II) and late EECs was first identified to delineate late EECs at the genomics level. ERBB2 and CCR1 were genes activated in late EECs, while APBA2 (MINT2) and CDK inhibitor p16 tumor suppressors in early EECs. MAPK pathway was significantly up in late EECs, indicating drugs targeting this canonical pathway might be useful for treating advanced EECs. A six-gene mini-signature was further identified to differentiate early from advanced EECs in both the training and testing datasets. Advanced, invasive EECs possessed a clear EpiSC gene expression pattern, explaining partly why these tumors are more malignant. CONCLUSIONS: Our work provides new insights into the pathogenesis of EECs and reveals a previously unknown link between adult stem cells and the histopathological traits of EECs. Shared EpiSC genes in late EECs may contribute to the stem cell-like phenotypes shown by advanced tumors and hold the potential of being candidate therapeutic targets and novel prognosis biomarkers.
Subject(s)
Carcinoma, Endometrioid/genetics , Endometrial Neoplasms/genetics , Epithelial Cells/cytology , Epithelial Cells/metabolism , Gene Expression Regulation, Neoplastic/physiology , Stem Cells/cytology , Stem Cells/metabolism , Adult , Aged , Aged, 80 and over , Cadherins/genetics , Carrier Proteins/genetics , Computational Biology , Cyclin-Dependent Kinase Inhibitor p16/genetics , Female , Gene Expression Regulation, Neoplastic/genetics , Humans , Immunohistochemistry , Middle Aged , Neoplasm Staging , Nerve Tissue Proteins/genetics , Oligonucleotide Array Sequence Analysis , Receptor, ErbB-2/genetics , Receptor, ErbB-2/metabolism , Receptors, CCR1/geneticsABSTRACT
The effects of lecithin and pectin on riboflavin-photosensitized oxidation of orange oil in a multilayered oil-in-water emulsion are studied by response surface methodology. Lecithin and pectin contents are two variables studied. Mean oil droplet size, viscosity, and ζ-potential are investigated for evaluation of emulsion stability. Headspace oxygen depletion, increase of conjugated diene value, and released amounts of limonene and carvone are used as responses to evaluate the oxidative stability of orange oil in this emulsion. The results show that both lecithin and pectin contents have significant effects (p < 0.05) on the oxidative stability of orange oil in the multilayered emulsion during photosensitized oxidation. No interactive effect (p < 0.05) is found between the lecithin and pectin contents. To achieve optimal oxidative stability, the suggested values in ratio for lecithin and pectin contents are 14.1 ± 0.5 and 19 ± 0.7, respectively.