TY - JOUR
T1 - Low-dose paclitaxel reduces S100A4 nuclear import to inhibit invasion and hematogenous metastasis of cholangiocarcinoma
AU - Cadamuro, Massimiliano
AU - Spagnuolo, Gaia
AU - Sambado, Luisa
AU - Indraccolo, Stefano
AU - Nardo, Giorgia
AU - Rosato, Antonio
AU - Brivio, Simone
AU - Caslini, Chiara
AU - Stecca, Tommaso
AU - Massani, Marco
AU - Bassi, Nicolò
AU - Novelli, Eugenio
AU - Spirli, Carlo
AU - Fabris, Luca
AU - Strazzabosco, Mario
PY - 2016/8/15
Y1 - 2016/8/15
N2 - Nuclear expression of the calcium-binding protein S100A4 is a biomarker of increased invasiveness in cholangiocarcinoma, a primary liver cancer with scarce treatment opportunities and dismal prognosis. In this study, we provide evidence that targeting S100A4 nuclear import by low-dose paclitaxel, a microtubulestabilizing agent, inhibits cholangiocarcinoma invasiveness and metastatic spread. Administration of low-dose paclitaxel to established (EGI-1) and primary (CCA-TV3) cholangiocarcinoma cell lines expressing nuclear S100A4 triggered a marked reduction in nuclear expression of S100A4 without modifying its cytoplasmic levels, an effect associated with a significant decrease in cell migration and invasiveness. While low-dose paclitaxel did not affect cellular proliferation, apoptosis, or cytoskeletal integrity, it significantly reduced SUMOylation of S100A4, a critical posttranslational modification that directs its trafficking to the nucleus. This effect of low-dose paclitaxel was reproduced by ginkolic acid, a specific SUMOylation inhibitor. Downregulation of nuclear S100A4 by low-dose paclitaxel was associated with a strong reduction in RhoA and Cdc42 GTPase activity, MT1-MMP expression, and MMP-9 secretion. In an SCID mouse xenograft model, low-dose metronomic paclitaxel treatment decreased lung dissemination of EGI-1 cells without significantly affecting their local tumor growth. In the tumor mass, nuclear S100A4 expression by cholangiocarcinoma cells was significantly reduced, whereas rates of proliferation and apoptosis were unchanged. Overall, our findings highlight nuclear S100A4 as a candidate therapeutic target in cholangiocarcinoma and establish a mechanistic rationale for the use of low-dose paclitaxel in blocking metastatic progression of cholangiocarcinoma.
AB - Nuclear expression of the calcium-binding protein S100A4 is a biomarker of increased invasiveness in cholangiocarcinoma, a primary liver cancer with scarce treatment opportunities and dismal prognosis. In this study, we provide evidence that targeting S100A4 nuclear import by low-dose paclitaxel, a microtubulestabilizing agent, inhibits cholangiocarcinoma invasiveness and metastatic spread. Administration of low-dose paclitaxel to established (EGI-1) and primary (CCA-TV3) cholangiocarcinoma cell lines expressing nuclear S100A4 triggered a marked reduction in nuclear expression of S100A4 without modifying its cytoplasmic levels, an effect associated with a significant decrease in cell migration and invasiveness. While low-dose paclitaxel did not affect cellular proliferation, apoptosis, or cytoskeletal integrity, it significantly reduced SUMOylation of S100A4, a critical posttranslational modification that directs its trafficking to the nucleus. This effect of low-dose paclitaxel was reproduced by ginkolic acid, a specific SUMOylation inhibitor. Downregulation of nuclear S100A4 by low-dose paclitaxel was associated with a strong reduction in RhoA and Cdc42 GTPase activity, MT1-MMP expression, and MMP-9 secretion. In an SCID mouse xenograft model, low-dose metronomic paclitaxel treatment decreased lung dissemination of EGI-1 cells without significantly affecting their local tumor growth. In the tumor mass, nuclear S100A4 expression by cholangiocarcinoma cells was significantly reduced, whereas rates of proliferation and apoptosis were unchanged. Overall, our findings highlight nuclear S100A4 as a candidate therapeutic target in cholangiocarcinoma and establish a mechanistic rationale for the use of low-dose paclitaxel in blocking metastatic progression of cholangiocarcinoma.
UR - http://www.scopus.com/inward/record.url?scp=84982104852&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84982104852&partnerID=8YFLogxK
U2 - 10.1158/0008-5472.CAN-16-0188
DO - 10.1158/0008-5472.CAN-16-0188
M3 - Article
AN - SCOPUS:84982104852
VL - 76
SP - 4775
EP - 4784
JO - Journal of Cancer Research
JF - Journal of Cancer Research
SN - 0008-5472
IS - 16
ER -