KB-15 is a STAT3 inhibitor exhibiting significant antiproliferative activity against AGS gastric cancer cells (IC50 = 0.29 μM) and BGC-823 gastric cancer cells (IC50 = 0.65 μM). It exerts its antitumor effects by inhibiting STAT3 phosphorylation, downregulating HO-1 expression, and promoting intracellular reactive oxygen species (ROS) accumulation. Additionally, KB-15 induces G0/G1 phase cell cycle arrest and apoptosis while hindering colony formation and migration in gastric cancer cells. In the BGC-823 subcutaneous xenograft model, KB-15 demonstrates excellent antitumor efficacy.

KB-15 exhibits potent antiproliferative effects on AGS gastric cancer cells (IC50 = 0.29 μM) and BGC-823 gastric cancer cells (IC50 = 0.65 μM) over 72 hours. It demonstrates significant colony formation inhibitory activity on both AGS and BGC-823 cells at concentrations of 0.25-2 μM over 14 days. Additionally, KB-15 strongly induces ROS in BGC-823 cells at 0.5-2 μM within 24 hours. It effectively causes G0/G1 phase cell cycle arrest and apoptosis in AGS and BGC-823 cells at concentrations between 0.25-2 μM over 24-36 hours. Furthermore, KB-15 inhibits STAT3 activation in a concentration-dependent manner and downregulates HO-1 expression in BGC-823 cells at 0.5-2 μM within 24 hours.

The compound KB-15 (2.5 mg/kg, administered intraperitoneally, daily for 14 consecutive days) has demonstrated significant antitumor activity in a subcutaneous xenograft model using BGC-823 cells.