Folate receptor-targeted pH-sensitive liposomes loaded with TGX-221 against prostate cancer by inhibiting PI3K/110β signaling†

Prostate cancer (PCa) is the most common cancer in men and the leading cause of cancer death worldwide. Overactivation of PI3K signaling has been reported to be associated with PCa. TGX221 is an effective specific inhibitor of PI3K, but its clinical application is greatly limited due to its poor solubility. Herein, by using folic acid-PEG-cholesterol semi-succinate (FA-PEG-CHEMS) as the targeting component, we developed a folate receptor-targeted pH-sensitive liposomal delivery system loaded with TGX221 (FA-Lip-TGX221) that could realize effective delivery and controlled release of drugs in the tumor. The prepared liposomes exhibited a uniform particle size and high stability. In addition, FA-Lip-TGX221 could be effectively internalized by PC-3 cells due to its ability to target folate receptors, thereby accumulating in tumor tissues. Meanwhile, in vitro and in vivo experiments suggested that FA-Lip-TGX221 could activate the PERK-ATF4-CHOP signaling pathway by inhibiting PI3K/110β signaling in PCa, thus significantly promoting endoplasmic reticulum (ER) stress-mediated cancer cell death. In conclusion, FA-Lip-TGX221 is a promising nano-delivery vehicle for the treatment of PCa, and also provide valuable references for all tumors overexpressing folate receptors.