TY - JOUR
T1 - Profilin-1 downregulation has contrasting effects on early vs late steps of breast cancer metastasis
AU - Ding, Z.
AU - Joy, M.
AU - Bhargava, R.
AU - Gunsaulus, M.
AU - Lakshman, N.
AU - Miron-Mendoza, M.
AU - Petroll, M.
AU - Condeelis, J.
AU - Wells, A.
AU - Roy, P.
N1 - Funding Information:
This work was supported by grants from the National Cancer Institute of the National Institute of Health (2R01CA108607-07) and the Magee Women’s Research Institute to PR.
PY - 2014/4/17
Y1 - 2014/4/17
N2 - Profilin1 (Pfn1), a ubiquitously expressed actin-binding protein, has an indispensable role in migration and proliferation of normal cells. Seemingly contrary to its essential cellular functions, Pfn1's expression is downregulated in breast cancer, the significance of which is unclear. In this study, expression profiling of Pfn1 in human breast cancer specimens correlates lower Pfn1 expression levels with propensity to metastasize. Xenograft experiments further establish a causal relationship between loss of Pfn1 expression and increased dissemination of breast cancer cells (BCCs) from the primary mammary tumor. BCCs exhibit a hyperinvasive phenotype (marked by matrix metalloproteinase-9 upregulation, faster invasion through collagen matrix) and acquire increased proficiency to transmigrate through endothelial barrier (an obligatory step for vascular dissemination) when Pfn1 expression is suppressed. In Pfn1-deficient cells, hyperinvasiveness involves a phosphatidylinositol 3-kinase-PI(3,4)P 2 signaling axis while augmented transendothelial migration occurs in a vascular endothelial growth factor-dependent manner. Contrasting these dissemination promoting activities, loss of Pfn1, however, dramatically inhibits metastatic outgrowth of disseminated BCCs, suggesting that Pfn1 has a key role in the metastatic colonization process. In summary, this study shows that Pfn1 has a dichotomous role in early vs late steps of breast cancer metastasis.
AB - Profilin1 (Pfn1), a ubiquitously expressed actin-binding protein, has an indispensable role in migration and proliferation of normal cells. Seemingly contrary to its essential cellular functions, Pfn1's expression is downregulated in breast cancer, the significance of which is unclear. In this study, expression profiling of Pfn1 in human breast cancer specimens correlates lower Pfn1 expression levels with propensity to metastasize. Xenograft experiments further establish a causal relationship between loss of Pfn1 expression and increased dissemination of breast cancer cells (BCCs) from the primary mammary tumor. BCCs exhibit a hyperinvasive phenotype (marked by matrix metalloproteinase-9 upregulation, faster invasion through collagen matrix) and acquire increased proficiency to transmigrate through endothelial barrier (an obligatory step for vascular dissemination) when Pfn1 expression is suppressed. In Pfn1-deficient cells, hyperinvasiveness involves a phosphatidylinositol 3-kinase-PI(3,4)P 2 signaling axis while augmented transendothelial migration occurs in a vascular endothelial growth factor-dependent manner. Contrasting these dissemination promoting activities, loss of Pfn1, however, dramatically inhibits metastatic outgrowth of disseminated BCCs, suggesting that Pfn1 has a key role in the metastatic colonization process. In summary, this study shows that Pfn1 has a dichotomous role in early vs late steps of breast cancer metastasis.
KW - breast cancer
KW - metastasis
KW - profilin-1
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U2 - 10.1038/onc.2013.166
DO - 10.1038/onc.2013.166
M3 - Article
C2 - 23686314
AN - SCOPUS:84899459598
SN - 0950-9232
VL - 33
SP - 2065
EP - 2074
JO - Oncogene
JF - Oncogene
IS - 16
ER -