1 / 20

10 Minutes Talk

10 Minutes Talk. 吳 華 席 Hua-Hsi Wu, MD OB/GYN, VGH-TPE Aug 12, 2008. Ovarian cancer, MicroRNA, Exosome. Introduction Ovarian cancer. Worldwide, 6th most common in female & 125,000 deaths annually 75% diagnosed as extra-ovarian dz (EM ca 73%, Breast ca 55% & Cx ca 50% in stage 1)

osman
Download Presentation

10 Minutes Talk

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 10 Minutes Talk 吳 華 席 Hua-Hsi Wu, MD OB/GYN, VGH-TPE Aug 12, 2008

  2. Ovarian cancer, MicroRNA, Exosome

  3. IntroductionOvarian cancer • Worldwide, 6th most common in female & 125,000 deaths annually • 75% diagnosed as extra-ovarian dz (EM ca 73%, Breast ca 55% & Cx ca 50% in stage 1) • 5-yr survival: stage 1 > 90%, advanced stage 21% • How to early Dx?

  4. IntroductionMicroRNA • Small (21-25 nucleotides in length) non-coding RNAs • Suppress the translation of target mRNAs by binding to their 3” untranslateed region • Post-transcriptional silencing • Cleavage of homologus mRNA • Specific inhibition of protein synthesis • Critical regulator of cellular processes • Proliferation, differentiation, development & cell death

  5. IntroductionMicroRNA • Distinct MicroRNAs signature, classify human cancers • Ovarian cancers: • miR-21, miR-141, miR-200a, miR-200b, miR-200c, miR-203, miR-205 & miR-214 • Up-modulation of specific microRNA could be the amplification of its gene. • Is microRNAsignature better than mRNA signature, in cnacer • Dx, staging, progression, and response to treatment

  6. Biogenesis of microRNAs

  7. Detailed structures of pri-, pre- and mature miRNAs

  8. IntroductionExosome • small (50-100nm) membrane vesicles of endocytic origin, in the peripheral circulation (of ovarian cancer patients was found initially in 1979) • Source • Except cancers, including reticulocytes, dendritic cells, B cells, T cells, mast cells, epithelial cells, and embryonic cells. • All exosomes share certain common characteristics (structures, size, density & general protein composition)

  9. IntroductionExosome • Cell-cell communication • Directly by surface expressed ligands • By transferring molecules between cells • Exosomes contains both cellular mRNA and miRNAs • While tumor-derived exosomes exhibit some common, shared proteins, they also express an array of tumor antigens that reflect the originating tumor cells.

  10. Material and Methods • Serum & biopsied tissue • Serous papillary adenocarcinoma • Stage I n=10, stage II n=10, stage III n=20, stage IV n=10 • Ovarian adenoma n=10 • NED of ovarian diseases n=10 • Isolation of circulating exosomes • MACS (EpCAM, anti-epithelial cell adhesion molecules) • Isolation & profiling of miRNAs • mirVana microRNA isolation kit

  11. Results

  12. Panel A: The levels of circulating tumor-derived exosomes compared to stage of ovarian cancer Panel B: Electron micrograph of circulating exosomes isolated by magnetic beads.

  13. Presence of small RNA associated with circulating EpCAM-positive exosomes from ovarian cancer patients

  14. **Intensities for specific microRNAs derived from the advanced-staged ovarian tumors (□) and from EpCAM-positive exosomes (■) isolated from the sera of these patients. **miR-21,miR-141, miR-200a, miR-200b, miR-200c, miR-203, miR-205, and miR-214 have previously been demonstrated to be upregulated markers for ovarian cancer

  15. Comparison of miRNA with peripheral blood-derived exosomes and their corresponding tumors

  16. miRNAs in exosomescompared by stages

  17. Comparison of specific exosomal miRNAsimmediately after blood draw or 24, 48, & 96 hr later

  18. Appendix A

  19. Results • MicroRNA from ovarian tumor cells and exosomes from the same patients were positive for 218 of 467 mature microRNAs analyzed. • The levels of the 8 specific microRNAs were similar between cellular and exosomal microRNAs (exhibiting correlations from 0.71 to 0.90). While EpCAM-positive exosomes were detectable in both patients with benign ovarian disease and ovarian cancer, exosomal microRNA from ovarian • cancer patients exhibited similar profiles, which were significantly distinct from profiles observed in benign disease. Exosomal microRNA could not be detected in normal controls.

  20. Conclusions • These results suggest that microRNA profiling of circulating tumor exosomes could potentially be used as surrogate diagnosticmarkers for biopsy profiling, extending its utility to screening asymptomatic populations.

More Related