Figure 3.

Blocking Ca²⁺ store operated calcium channels or inhibiting Ca²⁺ entry into mitochondria impairs MTI-101 induced cell death. (A) NCI-H929 and (B) U266 MM cells were pretreated with 50 μM-APB and 5 μM Ru360 for 30 min or vehicle control (VC). After 30 min cells were treated with 10 or 20 μM of MTI-101, respectively, for 2 hr. MTI-101 specific cell death was measured by FACS analysis. Shown is a representative experiment performed in triplicate. (C) NCI-H929 and (D) U266 MM cells were pretreated with 50 µM of 2-APB followed by treatment with 10 or 20 µM of MTI-101, respectively. Ca²⁺ levels were measured by fluo4 AM. The Y-axis is depicted as gray scale units (GSU or pixel intensity).