Cargando…

Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer

BACKGROUND: Ovarian cancer is a metastatic disease and one of the leading causes of gynaecology malignancy-related deaths in women. Cancer stem cells (CSCs) are key contributors of cancer metastasis and relapse. Integrins are a family of cell surface receptors which allow interactions between cells...

Descripción completa

Detalles Bibliográficos
Autores principales: Samardzija, Chantel, Luwor, Rodney B., Quinn, Michael A., Kannourakis, George, Findlay, Jock K., Ahmed, Nuzhat
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939035/
https://www.ncbi.nlm.nih.gov/pubmed/27390927
http://dx.doi.org/10.1186/s12885-016-2458-z
_version_ 1782441951311691776
author Samardzija, Chantel
Luwor, Rodney B.
Quinn, Michael A.
Kannourakis, George
Findlay, Jock K.
Ahmed, Nuzhat
author_facet Samardzija, Chantel
Luwor, Rodney B.
Quinn, Michael A.
Kannourakis, George
Findlay, Jock K.
Ahmed, Nuzhat
author_sort Samardzija, Chantel
collection PubMed
description BACKGROUND: Ovarian cancer is a metastatic disease and one of the leading causes of gynaecology malignancy-related deaths in women. Cancer stem cells (CSCs) are key contributors of cancer metastasis and relapse. Integrins are a family of cell surface receptors which allow interactions between cells and their surrounding microenvironment and play a fundamental role in promoting metastasis. This study investigates the molecular mechanism which associates CSCs and integrins in ovarian cancer metastasis. METHODS: The expression of Oct4A in high-grade serous ovarian tumors and normal ovaries was determined by immunofluorescence analysis. The functional role of Oct4A was evaluated by generating stable knockdown (KD) of Oct4A clones in an established ovarian cancer cell line HEY using shRNA-mediated silencing. The expression of integrins in cell lines was evaluated by flow cytometry. Spheroid forming ability, adhesion and the activities of matrix metalloproteinases 9/2 (MMP-9/2) was measured by in vitro functional assays and gelatin zymography. These observations were further validated in in vivo mouse models using Balb/c nu/nu mice. RESULTS: We report significantly elevated expression of Oct4A in high-grade serous ovarian tumors compared to normal ovarian tissues. The expression of Oct4A in ovarian cancer cell lines correlated with their CSC-related sphere forming abilities. The suppression of Oct4A in HEY cells resulted in a significant diminution of integrin β1 expression and associated α5 and α2 subunits compared to vector control cells. This was associated with a reduced adhesive ability on collagen and fibronectin and decreased secretion of pro-MMP2 in Oct4A KD cells compared to vector control cells. In vivo, Oct4A knock down (KD) cells produced tumors which were significantly smaller in size and weight compared to tumors derived from vector control cells. Immunohistochemical analyses of Oct4A KD tumor xenografts demonstrated a significant loss of cytokeratin 7 (CK7), Glut-1 as well as CD34 and CD31 compared to vector control cell-derived xenografts. CONCLUSION: The expression of Oct4A may be crucial to promote and sustain integrin-mediated extracellular matrix (ECM) remodeling requisite for tumor metastasis in ovarian cancer patients.
format Online
Article
Text
id pubmed-4939035
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-49390352016-07-10 Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer Samardzija, Chantel Luwor, Rodney B. Quinn, Michael A. Kannourakis, George Findlay, Jock K. Ahmed, Nuzhat BMC Cancer Research Article BACKGROUND: Ovarian cancer is a metastatic disease and one of the leading causes of gynaecology malignancy-related deaths in women. Cancer stem cells (CSCs) are key contributors of cancer metastasis and relapse. Integrins are a family of cell surface receptors which allow interactions between cells and their surrounding microenvironment and play a fundamental role in promoting metastasis. This study investigates the molecular mechanism which associates CSCs and integrins in ovarian cancer metastasis. METHODS: The expression of Oct4A in high-grade serous ovarian tumors and normal ovaries was determined by immunofluorescence analysis. The functional role of Oct4A was evaluated by generating stable knockdown (KD) of Oct4A clones in an established ovarian cancer cell line HEY using shRNA-mediated silencing. The expression of integrins in cell lines was evaluated by flow cytometry. Spheroid forming ability, adhesion and the activities of matrix metalloproteinases 9/2 (MMP-9/2) was measured by in vitro functional assays and gelatin zymography. These observations were further validated in in vivo mouse models using Balb/c nu/nu mice. RESULTS: We report significantly elevated expression of Oct4A in high-grade serous ovarian tumors compared to normal ovarian tissues. The expression of Oct4A in ovarian cancer cell lines correlated with their CSC-related sphere forming abilities. The suppression of Oct4A in HEY cells resulted in a significant diminution of integrin β1 expression and associated α5 and α2 subunits compared to vector control cells. This was associated with a reduced adhesive ability on collagen and fibronectin and decreased secretion of pro-MMP2 in Oct4A KD cells compared to vector control cells. In vivo, Oct4A knock down (KD) cells produced tumors which were significantly smaller in size and weight compared to tumors derived from vector control cells. Immunohistochemical analyses of Oct4A KD tumor xenografts demonstrated a significant loss of cytokeratin 7 (CK7), Glut-1 as well as CD34 and CD31 compared to vector control cell-derived xenografts. CONCLUSION: The expression of Oct4A may be crucial to promote and sustain integrin-mediated extracellular matrix (ECM) remodeling requisite for tumor metastasis in ovarian cancer patients. BioMed Central 2016-07-08 /pmc/articles/PMC4939035/ /pubmed/27390927 http://dx.doi.org/10.1186/s12885-016-2458-z Text en © The Author(s). 2016 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research Article
Samardzija, Chantel
Luwor, Rodney B.
Quinn, Michael A.
Kannourakis, George
Findlay, Jock K.
Ahmed, Nuzhat
Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer
title Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer
title_full Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer
title_fullStr Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer
title_full_unstemmed Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer
title_short Coalition of Oct4A and β1 integrins in facilitating metastasis in ovarian cancer
title_sort coalition of oct4a and β1 integrins in facilitating metastasis in ovarian cancer
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939035/
https://www.ncbi.nlm.nih.gov/pubmed/27390927
http://dx.doi.org/10.1186/s12885-016-2458-z
work_keys_str_mv AT samardzijachantel coalitionofoct4aandb1integrinsinfacilitatingmetastasisinovariancancer
AT luworrodneyb coalitionofoct4aandb1integrinsinfacilitatingmetastasisinovariancancer
AT quinnmichaela coalitionofoct4aandb1integrinsinfacilitatingmetastasisinovariancancer
AT kannourakisgeorge coalitionofoct4aandb1integrinsinfacilitatingmetastasisinovariancancer
AT findlayjockk coalitionofoct4aandb1integrinsinfacilitatingmetastasisinovariancancer
AT ahmednuzhat coalitionofoct4aandb1integrinsinfacilitatingmetastasisinovariancancer