Role of intracellular calcium in proteasome inhibitor-induced endoplasmic reticulum stress, autophagy, and cell death.

ABSTRACT:

Purpose

Proteasome inhibition induces endoplasmic reticulum (ER) stress and compensatory autophagy to relieve ER stress. Disturbance of intracellular calcium homeostasis can lead to ER stress and alter the autophagy process. It has been suggested that inhibition of the proteasome disrupts intracellular calcium homeostasis. However, it is unknown if intracellular calcium affects proteasome inhibitor-induced ER stress and autophagy.

Methods

Human colon cancer HCT116 Bax positive and negative cell lines were treated with MG132, a proteasome inhibitor. BAPTA-AM, a cell permeable free calcium chelator, was used to modulate intracellular calcium levels. Autophagy and cell death were determined by fluorescence microscopy and immunoblot analysis.

Results

MG132 increased intra

SUBMITTER: Williams JA 

PROVIDER: S-EPMC3788613 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature