The role of beta1 integrin subfamily in anchorage-dependent apoptosis of breast carcinoma cells differing in multidrug resistance.
Integrin expression was investigated in MCF-7 human breast adenocarcinoma line and in the MCF-7Dox line, which was selected from MCF-7 by a resistance to multiple antitumor drugs (MDR). We have shown that acquisition of MDR was accompanied by a drastically reduced expression of some integrins of the beta1-subfamily (alpha2beta1, alpha3beta1, alpha6beta1) and of alpha vbeta5 intergin in the adenocarcinoma cells. In contrast, expression of alpha5beta1 integrin was markedly increased in the MDR cells. Along with multiple antitumor drug resistance, MCF-7Dox cells demonstrate elevated resistance to anchorage-dependent apoptosis (anoikis) and enhanced in vitro invasive activity. To elucidate the implication of beta1-integrins in the above phenotypic modifications, the effect of beta1-integrin signaling was assayed. Stimulation of beta1-mediated signaling was accomplished by treating of the cells with antibodies to the beta1-subunit common for members of the beta1-subfamily. These data show that activation of beta1-integrin signaling markedly upregulated anoikis of the adenocarcinoma cells.
Morozevich
G E
GE
Orekhovich Institute of Biomedical Chemistry, Russian Academy of Medical Sciences, Moscow, Russia.
Kozlova
N I
NI
Preobrazhenskaya
M E
ME
Ushakova
N A
NA
Eltsov
I A
IA
Shtil
A A
AA
Berman
A E
AE
D023102:Anoikis / Q000502:physiology*; D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D018432:Drug Resistance, Multiple; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D038982:Integrin alpha2beta1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D039201:Integrin alpha3beta1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D039121:Integrin alpha6beta1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D019012:Integrin beta1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D038982:Integrin alpha2beta1; D039201:Integrin alpha3beta1; D039121:Integrin alpha6beta1; D019012:Integrin beta1