The inhibitory effect of TU-100 on hepatic stellate cell activation in the tumor microenvironment

Yuma Wada; Kazunori Tokuda; Yuji Morine; Shohei Okikawa; Shoko Yamashita; Tetsuya Ikemoto; Satoru Imura; Yu Saito; Shinichiro Yamada; Mitsuo Shimada

doi:10.18632/oncotarget.27835

The inhibitory effect of TU-100 on hepatic stellate cell activation in the tumor microenvironment

Oncotarget. 2020 Dec 8;11(49):4593-4604. doi: 10.18632/oncotarget.27835.

Authors

Yuma Wada^{1

2}, Kazunori Tokuda^{1

2}, Yuji Morine¹, Shohei Okikawa¹, Shoko Yamashita¹, Tetsuya Ikemoto¹, Satoru Imura¹, Yu Saito¹, Shinichiro Yamada¹, Mitsuo Shimada¹

Affiliations

¹ Department of Surgery, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan.
² These authors contributed equally to this work.

Abstract

Introduction: The tumor microenvironment is involved in acquiring tumor malignancies of colorectal liver metastasis (CRLM). We have reported that TU-100 (Daikenchuto) suppresses hepatic stellate cell (HSC) activation in obstructive jaundice. In this study, we report new findings as the direct and indirect inhibitory effects of TU-100 on cancer cell growth through the suppression of HSC activation.

Materials and methods: The HSCs (LX2) were cultured in colon cancer cells (HCT116 and HT29)-conditioned medium (CM) with or without TU-100 treatment (90, 270, 900 μg/ml). Activated HSCs (aHSCs) were detected by α-SMA and IL-6 mRNA expressions and cytokine arrays of HSC's culture supernatants. Cancer cell growth was analyzed for proliferation and migration ability, compared with TU-100 treatment. To investigate the direct anti-tumor effect of TU-100, cancer cells were cultured in the presence of aHSC-CM and TU-100 (90, 270, 900) or aHSC-CM alone, and assessed autophagosomes, conversion to LC3-II protein, and Beclin-1 mRNA expression.

Results: Colon cancer-CM significantly increased α-SMA and IL-6 mRNA expressions of aHSC. α-SMA and IL-6 mRNA expressions of aHSC, and IL-6 secretions from aHSCs were significantly decreased with TU-100 (270, 900) treatment, compared to colon cancer-CM alone. Compared with normal culture medium, aHSC-CM led to a significantly increased cell number and modified HSC-CM (TU-100; 270, 900) significantly suppressed cancer cell growth and migration. TU-100 (900) treatment induced autophagy and significantly promoted the autophagic cell death.

Conclusions: TU-100 inhibited colon cancer cell malignant potential by both suppressing HSC activation and inducing directly autophagy of cancer cells.

Keywords: CRC; CRLM; HSC; IL-6; TU-100.