FIGURE 5.

VLX1570 exerted an antiproliferative effect on leukemia cells by apoptosis involved in ER stress induction. (A), (B) HL‐60, MDS‐L, MOLT‐4 and Jurkat cells were treated with 0‐500 nmol/L of VLX1570 for 3 h and the cell lysates were analyzed by immunoblotting analysis for detection of XBP‐1s, CHOP, ATF4, BiP, eIF2α, phospho‐eIF2α, and phospho‐IRE1α. For detection of the expression of XBP‐1s, ATF4, and CHOP, the nuclear fraction was extracted as described in the Materials and methods section. β‐actin was used as a loading control. The number of protein bands was measured by densitometry and the ratio was adjusted as 1.0 in the untreated sample and the changes of the ratio of treated samples relative to untreated sample were indicated