TY - JOUR
T1 - Integrin β1, osmosensing, and chemoresistance in mouse ehrlich carcinoma cells
AU - Sørensen, Belinda Halling
AU - Rasmussen, Line Jee Hartmann
AU - Broberg, Bjørn Sindballe
AU - Klausen, Thomas Kjær
AU - Sauter, Daniel Rafael Peter
AU - Lambert, Ian Henry
AU - Aspberg, Anders
AU - Hoffmann, Else Kay
PY - 2015/5/26
Y1 - 2015/5/26
N2 - Background/Aims: Altered expression of the integrin family of cell adhesion receptors has been associated with initiation, progression, and metastasis of solid tumors as well as in the development of chemoresistance. Here, we investigated the role of integrins, in particular integrin β 1 , in cell volume regulation and drug-induced apoptosis in adherent and non-adherent Ehrlich ascites cell lines. Methods: Adhesion phenotypes were verified by colorimetric cell-adhesion-assay. Quantitative real-time PCR and western blot were used to compare expression levels of integrin subunits. Small interfering RNA was used to silence integrin β 1 expression. Regulatory volume decrease (RVD) after cell swelling was studied with calcein-fluorescence-self-quenching and Coulter counter analysis. Taurine efflux was estimated with tracer technique. Caspase assay was used to determine apoptosis. Results: We show that adherent cells have stronger fibronectin binding and a significantly increased expression of integrin α 5 , α v , and β 1 at mRNA and protein level, compared to non-adherent cells. Knockdown of integrin β 1 reduced RVD of the adherent but not of the non-adherent cells. Efflux of taurine was unaffected. In contrast to non-adherent, adherent cells exhibited chemoresistance to chemotherapeutic drugs (cisplatin and gemcitabine). However, knockdown of integrin β 1 promoted cisplatin-induced caspase activity in adherent cells. Conclusion: Our data identifies integrin β 1 as a part of the osmosensing machinery and regulator of cisplatin resistance in adherent Ehrlich cells.
AB - Background/Aims: Altered expression of the integrin family of cell adhesion receptors has been associated with initiation, progression, and metastasis of solid tumors as well as in the development of chemoresistance. Here, we investigated the role of integrins, in particular integrin β 1 , in cell volume regulation and drug-induced apoptosis in adherent and non-adherent Ehrlich ascites cell lines. Methods: Adhesion phenotypes were verified by colorimetric cell-adhesion-assay. Quantitative real-time PCR and western blot were used to compare expression levels of integrin subunits. Small interfering RNA was used to silence integrin β 1 expression. Regulatory volume decrease (RVD) after cell swelling was studied with calcein-fluorescence-self-quenching and Coulter counter analysis. Taurine efflux was estimated with tracer technique. Caspase assay was used to determine apoptosis. Results: We show that adherent cells have stronger fibronectin binding and a significantly increased expression of integrin α 5 , α v , and β 1 at mRNA and protein level, compared to non-adherent cells. Knockdown of integrin β 1 reduced RVD of the adherent but not of the non-adherent cells. Efflux of taurine was unaffected. In contrast to non-adherent, adherent cells exhibited chemoresistance to chemotherapeutic drugs (cisplatin and gemcitabine). However, knockdown of integrin β 1 promoted cisplatin-induced caspase activity in adherent cells. Conclusion: Our data identifies integrin β 1 as a part of the osmosensing machinery and regulator of cisplatin resistance in adherent Ehrlich cells.
U2 - 10.1159/000374057
DO - 10.1159/000374057
M3 - Journal article
C2 - 25925201
SN - 1015-8987
VL - 36
SP - 111
EP - 132
JO - Cellular Physiology and Biochemistry
JF - Cellular Physiology and Biochemistry
IS - 1
ER -