gms | German Medical Science

128. Kongress der Deutschen Gesellschaft für Chirurgie

Deutsche Gesellschaft für Chirurgie

03.05. - 06.05.2011, München

Antisense inhibition of microRNA-21 and -221 in tumor-initiating stem-like cells modulates biological functions of pancreatic cancer including tumorigenesis, metastasis, and chemoresistance

Meeting Abstract

  • Ivan Ischenko - LMU Klinikum Großhadern, Chirurgische Klinik und Poliklinik, München
  • Peter Camaj - LMU Klinikum Großhadern, Chirurgische Klinik und Poliklinik, München
  • Karl-Walter Jauch - Universitätsklinikum der LMU München-Großhadern, Chirurgische Klinik und Poliklinik, München
  • Christiane J. Bruns - LMU Klinikum Großhadern, Chirurgische Klinik und Poliklinik, München

Deutsche Gesellschaft für Chirurgie. 128. Kongress der Deutschen Gesellschaft für Chirurgie. München, 03.-06.05.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. Doc11dgch330

DOI: 10.3205/11dgch330, URN: urn:nbn:de:0183-11dgch3301

Published: May 20, 2011

© 2011 Ischenko et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

Text

Introduction: Our preliminary studies identified a small population of pancreatic cancer cells with stem-like properties. These cells, called Side Population (SP) cells, were able to induce fast and aggressive tumor formation in nude mice. Cultured SP were able to differentiate into daughter SP or non-SP cells and were found to be highly chemoresistant. Furthermore, performed gene expression analysis showed a significant difference in the expression of more than 1300 genes in SP cells, among which the difference in microRNA expression between SP and non-SP cells was identified as the most interesting candidate for our further studies.

Materials and methods: Pancreatic cancer stem-like cells from highly metastatic cell line L3.6pl were identified and characterized by flow cytometry using Hoechst 33342 dye staining. The gene expression was assessed by Affymetrix and the results were further confirmed by quantitative RT-PCR. The antagomir transfection was performed using microRNA-21 and -221 oligonucleotide antisense. Tumor cell apoptosis, cell cycle progression, chemoresistance, and invasion were quantitated by propidium iodide staining and Boyden chamber assay, respectively.

Results: In our study, some microRNAs, including miR-21, miR-221, miR-211, and miR-30c-2 were significantly upregulated in stem-like SP from L3.6pl cells. Interestingly, in these cells both miR-21 and miR-221 were involved in the modulation of expression of more than 200 genes, including RASSF6, RAB2B, TP63, TP53INP1, TP53INP2, TET1, MAPK10, MAP2K6, CDK6, TNFRSF11B, SOCS6, STK33, and SMAD7. The administration of antagomir-21 and -221 significantly reduced the SP fracture, decreased SP cell differentiation, positively affected L3.6pl cell proliferation, invasion, and chemoresistance against gemcitabine and 5-Fluorouracil.

Conclusion: Our results demonstrate the significance of both microRNA-21 and -221 in tumor-initiating capability of stem-like tumor cells in pancreatic cancer. Both microRNAs contribute to the most important biological functions of pancreatic cancer including apoptosis, metastasis, and chemoresistance, and may further serve as a potential target for pancreatic cancer therapy.