Figure 2

MTI-101 triggers release of ER Ca²⁺stores and influx of Ca²⁺ entry by plasma membrane store operated channels (SOC). (A) MTI-101 mediated intracellular Ca²⁺ levels were measured by using Fura-2 dye. NCI-H929 cells were adhered to cell-tak coated plates and then incubated with Fura-2 dye +/− 2 uM U73122 for 30 min in PSS containing Ca²⁺ and PSS without Ca²⁺. Time-lapse images were taken every 10 seconds for 30 min after treatment with 3 µM MTI-101. A representative H929 cell closest to the median Ca²⁺ response of the whole population is shown. The peaks were then measured and subtracted from the baseline Ca²⁺ levels. A representative experiment for (B) NCI-H929 and (C) U266 is shown. (D and E) The total level of Ca²⁺ induced by MTI-101 was determined by measuring the area under the curve for each individual cell. A one-way ANOVA test determined significance (^#p > 0.05; *p < 0.05; n = 30 or greater). Shown is a representative experiment performed in triplicate.