Down-Regulation of Store-Operated Ca2+ Entry and Na+ Ca2+ Exchange in MCF-7 Breast Cancer Cells by Pharmacological JAK3 Inhibition.
Cell Physiol Biochem
; 38(4): 1643-51, 2016.
Article
en En
| MEDLINE
| ID: mdl-27119652
ABSTRACT
BACKGROUND/AIMS:
Oscillations of cytosolic Ca2+ activity ([Ca2+]i) participate in the orchestration of tumor cell proliferation. [Ca2+]i could be increased by intracellular Ca2+ release followed by store-operated Ca2+-entry (SOCE). [Ca2+]i could be decreased by Ca2+ extrusion via Na+/Ca2+ exchange. Mechanisms accomplishing SOCE include the pore-forming ion channel unit Orai1 and its regulator STIM1, Na+/Ca2+ exchanger isoforms include NCX1. In MCF-7 breast carcinoma cells Orai1 and NCX1 have previously been shown to be modified by pharmacological inhibition of Janus activated kinase JAK2. The present study explored whether SOCE and Na+/Ca2+ exchange are similarly sensitive to pharmacological JAK3 inhibition.METHODS:
MCF-7 breast carcinoma cells were studied in the absence and presence of the JAK3 inhibitor WHI-P154 (22 µM). [Ca2+]i was estimated from Fura-2-fluorescence, SOCE from increase of [Ca2+]i following Ca2+ re-addition after Ca2+-store depletion with sarcoendoplasmatic Ca2+-ATPase (SERCA) inhibitor thapsigargin (1 µM), and Na+/Ca2+ exchanger activity from increase of [Ca2+]i following extracellular Na+ removal. Transcript levels were quantified with RT-PCR.RESULTS:
Addition of ATP (100 µM) was followed by a rapid increase of [Ca2+]i, which was significantly blunted by WHI-P154. Thapsigargin-induced intracellular Ca2+ release was not appreciably influenced by WHI-P154. Subsequent SOCE was, however, significantly blunted by WHI-P154. WHI-P154 further significantly decreased Orai1 transcript levels. The increase of [Ca2+]i following extracellular Na+-removal and the NCX1 transcript levels were similarly decreased by WHI-P154.CONCLUSIONS:
The JAK3 inhibitor WHI-P154 decreases both, Orai1 and NCX1 transcript levels and thus impairs SOCE and Na+/Ca2+ exchange.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Calcio
/
Intercambiador de Sodio-Calcio
/
Janus Quinasa 3
Límite:
Female
/
Humans
Idioma:
En
Revista:
Cell Physiol Biochem
Asunto de la revista:
BIOQUIMICA
/
FARMACOLOGIA
Año:
2016
Tipo del documento:
Article