EGFR-targeted micelles containing near-infrared dye for enhanced photothermal therapy in colorectal cancer

Abstract

The purpose of this research was to investigate the effectiveness of epidermal growth factor receptor (EGFR) targeted micelles loaded with IR-780 (Cetuximab/IR-780/micelles) for generating tumor targeting, multimodal images, and photothermal therapy (PTT). We initially studied the cellular uptake of these micelles using the HCT-116 and SW-620 cell lines. HCT-116 (high expression of EGFR) and SW-620 (low expression of EGFR) cell lines were used to examine biodistribution and antitumor effects of Cetuximab/IR-780/micelles. Time-lapse near-IR fluorescence (NIRF) images also indicated the highest IR-780 accumulation from Cetuximab/IR-780/micelles in HCT-116 tumors (p<0.05). HCT-116 tumors in tumor-bearing mice exhibited significantly higher accumulations of Cetuximab/IR-780/111In-micelles than SW-620 tumors in Micro-SPECT/CT imaging and biodistribution studies (p<0.05). Dual-radioisotope Nano-SPECT/CT imaging of Cetuximab/131I-IR-780/111In-micelles demonstrated simultaneous high accumulation of both IR-780 and micelles in HCT-116 tumors, but not in SW-620 tumors. Regarding antitumor effects, following the Cetuximab/IR-780/micelles with PPT on day 6, all HCT-116 tumor-bearing mice were cured. In contrast, SW-620 tumors relapsed at 13days after treatment. In summary, we expect that the Cetuximab/IR-780/micelles could enhance the antitumor effects by PTT in EGFR overexpression colorectal cancers through effective drug delivery nanoparticles.