Presentation Information
[P01-143]Chemo-phototherapy via ICG-conjugated chondroitin sulfate nanoparticles: targeted erastin delivery with switchable ROS modulation in hepatocellular carcinoma
○JungHun Kang1, So-Yeol Yoo1, Jae-Young Lee1 (1. Seoul National University (Korea))
Keywords:
Hepatocellular carcinoma,Erastin,Chondroitin sulfate A nanomedicine,CD44–xCT axis,Photothermal and photodynamic therapy,Non-ferroptotic mechanisms,Cell cycle arrest
[Purpose] Erastin, a system xc- inhibitor capable of triggering ferroptosis, has emerged as a promising anticancer candidate. However, its clinical translation is hindered by poor aqueous solubility, rapid systemic clearance, and non-selective tissue distribution. This study aimed to develop ECINs, self-assembled nanoparticles composed of chondroitin sulfate A (CSA) conjugated with a propanesulfonate indocyanine green (psICG) derivative, to achieve CD44-targeted erastin delivery to hepatocellular carcinoma (HCC) with near-infrared (NIR) laser-activatable phototherapeutic enhancement.
[Method] CSA-psICG conjugates were synthesized via Steglich esterification at varying weight ratios (10:1-10:4). ECINs were prepared through co-dissolution of erastin and CSA-psICG followed by lyophilization and aqueous reconstitution. Physicochemical properties including particle size, zeta potential, encapsulation efficiency, colloidal stability, and drug release kinetics were characterized. CD44-mediated cellular uptake was evaluated in SK-HEP-1 (CD44-high) and Huh-7 (CD44-low) HCC cell lines using flow cytometry and confocal microscopy. The contribution of ferroptosis was assessed using ferrostatin-1 co-treatment and C11 BODIPY lipid peroxidation assays. Cell cycle distribution was analyzed by propidium iodide staining. In vivo biodistribution, pharmacokinetics, and antitumor efficacy were investigated in SK-HEP-1 xenograft mice, with or without 808-nm laser irradiation.
[Results] The optimized ECINs (CSA-psICG:erastin = 10:3, w/w) exhibited a mean diameter of 186.7 +/- 1.1 nm, a zeta potential of -39.79 +/- 0.44 mV, and an encapsulation efficiency of 93.0 +/- 0.8%, with sustained erastin release over 120 h. ECINs showed preferential uptake in CD44-overexpressing SK-HEP-1 cells. Notably, ferrostatin-1 did not attenuate the antiproliferative effect of ECINs, and no elevation of lipid ROS was detected, indicating a non-ferroptotic mechanism. Instead, ECINs induced G1-phase cell cycle arrest accompanied by downregulation of cyclin D1 and CDK2. In SK-HEP-1 xenograft mice, ECINs achieved 2.2-fold greater tumor accumulation of erastin compared to the free drug, while reducing pulmonary and splenic deposition by 203-fold and 19.1-fold, respectively. Combined with NIR laser irradiation, ECINs produced a 2.6-fold reduction in tumor volume relative to free erastin, with no detectable systemic toxicity.
[Consideration] The psICG moiety functions as a molecular switch, scavenging ROS under laser-off conditions to minimize unintended ferroptotic damage in healthy tissues, while generating photothermal heating and singlet oxygen upon laser activation to amplify antitumor efficacy at the tumor site. This switchable mechanism, combined with CD44-mediated active targeting, enables spatiotemporally controlled therapeutic intervention with a favorable safety profile.
[Conclusion] ECINs represent a promising dual-modality nanoplatform for CD44+/xCT+ HCC, integrating targeted chemotherapy with laser-activatable phototherapy through a non-ferroptotic mechanism. These findings support further development of ECINs toward clinical translation.
[Method] CSA-psICG conjugates were synthesized via Steglich esterification at varying weight ratios (10:1-10:4). ECINs were prepared through co-dissolution of erastin and CSA-psICG followed by lyophilization and aqueous reconstitution. Physicochemical properties including particle size, zeta potential, encapsulation efficiency, colloidal stability, and drug release kinetics were characterized. CD44-mediated cellular uptake was evaluated in SK-HEP-1 (CD44-high) and Huh-7 (CD44-low) HCC cell lines using flow cytometry and confocal microscopy. The contribution of ferroptosis was assessed using ferrostatin-1 co-treatment and C11 BODIPY lipid peroxidation assays. Cell cycle distribution was analyzed by propidium iodide staining. In vivo biodistribution, pharmacokinetics, and antitumor efficacy were investigated in SK-HEP-1 xenograft mice, with or without 808-nm laser irradiation.
[Results] The optimized ECINs (CSA-psICG:erastin = 10:3, w/w) exhibited a mean diameter of 186.7 +/- 1.1 nm, a zeta potential of -39.79 +/- 0.44 mV, and an encapsulation efficiency of 93.0 +/- 0.8%, with sustained erastin release over 120 h. ECINs showed preferential uptake in CD44-overexpressing SK-HEP-1 cells. Notably, ferrostatin-1 did not attenuate the antiproliferative effect of ECINs, and no elevation of lipid ROS was detected, indicating a non-ferroptotic mechanism. Instead, ECINs induced G1-phase cell cycle arrest accompanied by downregulation of cyclin D1 and CDK2. In SK-HEP-1 xenograft mice, ECINs achieved 2.2-fold greater tumor accumulation of erastin compared to the free drug, while reducing pulmonary and splenic deposition by 203-fold and 19.1-fold, respectively. Combined with NIR laser irradiation, ECINs produced a 2.6-fold reduction in tumor volume relative to free erastin, with no detectable systemic toxicity.
[Consideration] The psICG moiety functions as a molecular switch, scavenging ROS under laser-off conditions to minimize unintended ferroptotic damage in healthy tissues, while generating photothermal heating and singlet oxygen upon laser activation to amplify antitumor efficacy at the tumor site. This switchable mechanism, combined with CD44-mediated active targeting, enables spatiotemporally controlled therapeutic intervention with a favorable safety profile.
[Conclusion] ECINs represent a promising dual-modality nanoplatform for CD44+/xCT+ HCC, integrating targeted chemotherapy with laser-activatable phototherapy through a non-ferroptotic mechanism. These findings support further development of ECINs toward clinical translation.
Comment
To browse or post comments, you must log in.Log in