Therapeutic effect of the treatment for colorectal cancer with adenoviral vectors mediated estrogen receptor β gene therapy combined with thermotherapy

Introduction: Our preliminary study on repressing colorectal tumors by recombinant adenoviruses (Ads) delivering the human ERβ gene (Ad-ERβ) has achieved positive result. Methods: In this study, hydrophobic fluorescent dyes ICG-Der-01 was entrapped into the N-succinyl-N′-octyl chitosan (SOC) micelles to form the near infrared absorbing dyes SOC-ICG-Der-01 and SOC-ICG-Der-01 mediated near infrared laser (SOC-ICG-Der-01/NIR) thermotherapy was combined with Ad-ERβ gene therapy to regress colon cancer in vivo. Results: Firstly, the antitumor efficacies of SOC-ICG-Der-01/NIR thermotherapy were investigated on S180 ascites tumor-bearing mice. Results indicated that, the average tumor volume of SOC-ICG-Der-01/NIR group was the smallest among the three treatment groups. Then, thermotherapy with SOC-ICG-Der-01/NIR combined with Ad-ERβ gene therapy to treat HCT-116 colon cancer xenograft model was investigated. Further results demonstrated that, SOC-ICG-Der-01/NIR thermotherapy showed the significantly inhibitory efficiency compared with control group and Ad-ERβ enhanced the therapeutic effect of SOC-ICG-Der-01/NIR. Conclusion: These findings demonstrated that combined administration of Ad-ERβ with SOC-ICG-Der-01/NIR thermotherapy represents a promising colon cancer therapeutic strategy.