An in vitro study on sonodynamic treatment of human colon cancer cells using sinoporphyrin sodium as sonosensitizer

Yuanyuan Shen,Xiaojun Zeng,Tie Chen,Xin Chen,Siping Chen,Zhaoke Pi,Yaxin Hu,Lanhui Huang,Jianquan Ou

doi:10.1186/s12938-020-00797-w

Abstract

BackgroundColorectal cancer is the third leading cause of cancer-related deaths worldwide. Sonodynamic therapy (SDT) is an emerging cancer therapy, and in contrast to photodynamic therapy, could non-invasively reach deep-seated tissues and locally activates a sonosensitizer preferentially accumulated in the tumor area to produce cytotoxicity effects. In comparison with traditional treatments, SDT may serve as an alternative strategy for human colon cancer treatment. Here, we investigated the sonodynamic effect using sinoporphyrin sodium (DVDMS) as a novel sonosensitizer on human colon cancer cells in vitro.ResultsThe absorption spectra of DVDMS revealed maximum absorption at 363 nm wavelength and emission peak at 635 nm. Confocal microscopy images revealed the DVDMS was primarily localized in the cytoplasm, while no evident signal was detected within the nuclei. Flow cytometry analysis showed rapid intracellular uptake of DVDMS by two types of human colon cancer cells (HCT116 and RKO). Cell viability of HCT116 was tolerant with the concentration of DVDMS up to 20 µg/mL, while the case of RKO was 5 µg/mL. In comparison with the control group, the SDT-treated groups of these two types of human colon cancer cells showed significant increase in cellular apoptosis and necrosis ratio. Increased intracellular reactive oxygen species (ROS) production was detected, indicating the involvement of ROS in mediating SDT effects.ConclusionDVDMS results an effective sonosensitizer for the ultrasound-mediated cancer cell killing, and its anticancer effect seems to rely on its ability to produce ROS under ultrasound exposure.

Highlights

Colorectal cancer is the third leading cause of cancer-related deaths worldwide
Cytotoxicity analysis of Sinoporphyrin sodium (DVDMS) To examine the cytotoxicity of DVDMS, the viability of human colon cancer cells (HCT116, RKO) and normal colon cells (NCM460) incubated with various concentrations of DVDMS (0, 1, 2, 5, 10, 15, and 20 μg/mL) for 6 h was analyzed
Intracellular uptake of DVDMS The intracellular uptake of DVDMS by HCT116 and RKO cells were examined by imaging the fluorescence signal of DVDMS under a confocal microscope

Summary

Introduction

Colorectal cancer is the third leading cause of cancer-related deaths worldwide. Sonodynamic therapy (SDT) is an emerging cancer therapy, and in contrast to photodynamic therapy, could non-invasively reach deep-seated tissues and locally activates a sonosensitizer preferentially accumulated in the tumor area to produce cytotoxicity effects. Sonodynamic therapy (SDT) has evolved as a promising therapeutic approach for cancer treatment over recent decades This technique involves the cytotoxic effects elicited by non-toxic chemical agents preferentially retained in tumor tissue upon exposure to relatively low-intensity ultrasound. It was reported that SDT mediated by gold nanoparticles in conjugation to protoporphyrin IX (PpIX) could reduce the volume of colon carcinoma tumors and prolong the survival time of tumor-bearing mice [10]. These results imply that SDT may be potentially useful for the treatment of human colon cancer

Methods

Results

Conclusion