Cargando…

Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy

INTRODUCTION: We have previously identified a rare subpopulation of variant human mammary epithelial cells (vHMEC) with repressed p16(INK4A )that exist in disease-free women yet display premalignant properties, suggesting that they have engaged the process of malignant transformation. In order to ga...

Descripción completa

Detalles Bibliográficos
Autores principales: Dumont, Nancy, Crawford, Yongping G, Sigaroudinia, Mahvash, Nagrani, Shefali S, Wilson, Matthew B, Buehring, Gertrude C, Turashvili, Gulisa, Aparicio, Samuel, Gauthier, Mona L, Fordyce, Colleen A, McDermott, Kimberly M, Tlsty, Thea D
Formato: Texto
Lenguaje:English
Publicado: BioMed Central 2009
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2815551/
https://www.ncbi.nlm.nih.gov/pubmed/19995452
http://dx.doi.org/10.1186/bcr2457
_version_ 1782177026416836608
author Dumont, Nancy
Crawford, Yongping G
Sigaroudinia, Mahvash
Nagrani, Shefali S
Wilson, Matthew B
Buehring, Gertrude C
Turashvili, Gulisa
Aparicio, Samuel
Gauthier, Mona L
Fordyce, Colleen A
McDermott, Kimberly M
Tlsty, Thea D
author_facet Dumont, Nancy
Crawford, Yongping G
Sigaroudinia, Mahvash
Nagrani, Shefali S
Wilson, Matthew B
Buehring, Gertrude C
Turashvili, Gulisa
Aparicio, Samuel
Gauthier, Mona L
Fordyce, Colleen A
McDermott, Kimberly M
Tlsty, Thea D
author_sort Dumont, Nancy
collection PubMed
description INTRODUCTION: We have previously identified a rare subpopulation of variant human mammary epithelial cells (vHMEC) with repressed p16(INK4A )that exist in disease-free women yet display premalignant properties, suggesting that they have engaged the process of malignant transformation. In order to gain insight into the molecular alterations required for vHMEC to progress to malignancy, and to characterize the epigenetic events associated with early progression, we examined the effect of oncogenic stress on the behavior of these cells. METHODS: HMEC that express p16(INK4A )and vHMEC that do not, were transduced with constitutively active Ha-rasV12 and subsequently exposed to serum to determine whether signals from the cellular microenvironment could cooperate with ras to promote the malignant transformation of vHMEC. Epigenetic alterations were assessed using methylation-specific polymerase chain reaction (PCR). RESULTS: vHMEC expressing Ha-rasV12 (vHMEC-ras) bypassed the classic proliferative arrest that has been previously documented in normal fibroblasts following oncogenic stress, and that we also observe here in normal HMEC. Moreover, vHMEC-ras cells exhibited many additional alterations that are observed during progression to malignancy such as the generation of chromosomal abnormalities, upregulation of telomerase activity, immortalization following exposure to serum, and anchorage-independent growth, but they did not form tumors following orthotopic injection in vivo. Associated with their early progression to malignancy was an increase in the number of genes methylated, two of which (RASSF1A and SFRP1) were also methylated in other immortalized mammary cell lines as well as in breast cancer cells and tissues. CONCLUSIONS: We have characterized a mammary progression model that recapitulates molecular and methylation alterations observed in many breast cancers. Our data suggest that concomitant methylation of RASSF1A and SFRP1 marks an early event in mammary transformation and may thus have prognostic potential.
format Text
id pubmed-2815551
institution National Center for Biotechnology Information
language English
publishDate 2009
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-28155512010-02-03 Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy Dumont, Nancy Crawford, Yongping G Sigaroudinia, Mahvash Nagrani, Shefali S Wilson, Matthew B Buehring, Gertrude C Turashvili, Gulisa Aparicio, Samuel Gauthier, Mona L Fordyce, Colleen A McDermott, Kimberly M Tlsty, Thea D Breast Cancer Res Research article INTRODUCTION: We have previously identified a rare subpopulation of variant human mammary epithelial cells (vHMEC) with repressed p16(INK4A )that exist in disease-free women yet display premalignant properties, suggesting that they have engaged the process of malignant transformation. In order to gain insight into the molecular alterations required for vHMEC to progress to malignancy, and to characterize the epigenetic events associated with early progression, we examined the effect of oncogenic stress on the behavior of these cells. METHODS: HMEC that express p16(INK4A )and vHMEC that do not, were transduced with constitutively active Ha-rasV12 and subsequently exposed to serum to determine whether signals from the cellular microenvironment could cooperate with ras to promote the malignant transformation of vHMEC. Epigenetic alterations were assessed using methylation-specific polymerase chain reaction (PCR). RESULTS: vHMEC expressing Ha-rasV12 (vHMEC-ras) bypassed the classic proliferative arrest that has been previously documented in normal fibroblasts following oncogenic stress, and that we also observe here in normal HMEC. Moreover, vHMEC-ras cells exhibited many additional alterations that are observed during progression to malignancy such as the generation of chromosomal abnormalities, upregulation of telomerase activity, immortalization following exposure to serum, and anchorage-independent growth, but they did not form tumors following orthotopic injection in vivo. Associated with their early progression to malignancy was an increase in the number of genes methylated, two of which (RASSF1A and SFRP1) were also methylated in other immortalized mammary cell lines as well as in breast cancer cells and tissues. CONCLUSIONS: We have characterized a mammary progression model that recapitulates molecular and methylation alterations observed in many breast cancers. Our data suggest that concomitant methylation of RASSF1A and SFRP1 marks an early event in mammary transformation and may thus have prognostic potential. BioMed Central 2009 2009-12-08 /pmc/articles/PMC2815551/ /pubmed/19995452 http://dx.doi.org/10.1186/bcr2457 Text en Copyright ©2009 Dumont et al.; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research article
Dumont, Nancy
Crawford, Yongping G
Sigaroudinia, Mahvash
Nagrani, Shefali S
Wilson, Matthew B
Buehring, Gertrude C
Turashvili, Gulisa
Aparicio, Samuel
Gauthier, Mona L
Fordyce, Colleen A
McDermott, Kimberly M
Tlsty, Thea D
Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy
title Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy
title_full Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy
title_fullStr Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy
title_full_unstemmed Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy
title_short Human mammary cancer progression model recapitulates methylation events associated with breast premalignancy
title_sort human mammary cancer progression model recapitulates methylation events associated with breast premalignancy
topic Research article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2815551/
https://www.ncbi.nlm.nih.gov/pubmed/19995452
http://dx.doi.org/10.1186/bcr2457
work_keys_str_mv AT dumontnancy humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT crawfordyongpingg humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT sigaroudiniamahvash humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT nagranishefalis humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT wilsonmatthewb humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT buehringgertrudec humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT turashviligulisa humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT apariciosamuel humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT gauthiermonal humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT fordycecolleena humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT mcdermottkimberlym humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy
AT tlstythead humanmammarycancerprogressionmodelrecapitulatesmethylationeventsassociatedwithbreastpremalignancy