PROM1 and gastric cancer: Recent studies have posed the involvement of autophagy in drug resistance [15]; for example, CD133, an important CSC marker, was discovered to enhance cisplatin resistance in gastric cancer stem cells (GCSCs) by boosting cell proliferation, anti-apoptotic activity, and autophagy capability through the activation of the PI3K/AKT/mTOR signaling pathway, and CD133 knockdown was able to reverse cisplatin resistance [105].