figure
posted on 2023-03-31, 18:23 authored by Koji Munakata, Mamoru Uemura, Shinji Tanaka, Kenji Kawai, Tomohiro Kitahara, Masaaki Miyo, Yoshihiro Kano, Shinpei Nishikawa, Takahito Fukusumi, Yusuke Takahashi, Taishi Hata, Junichi Nishimura, Ichiro Takemasa, Tsunekazu Mizushima, Masakazu Ikenaga, Takeshi Kato, Kohei Murata, John M. Carethers, Hirofumi Yamamoto, Yuichiro Doki, Masaki Mori EID3 was identified by microarray analysis. The expression of EID3 was confirmed by PCR and western blotting. (A) The mRNA expression of EID3 was significantly enriched in LPACs of HCT116, KM12SM and DLD1 compared to non-LPACs, except SW480 which just missed statistical significance (p=0.0555). (B) Western blotting was also performed for checking the expression of EID3 protein in LPACs and non-LPACs using EID3 antibody (Abcam, Cambridge, UK, ab124447), but the evaluation was difficult, because expression of EID3 is low in humans as per previous report (31, 32). * p<0.05.
Funding
JSPS
Takeda Science Foundation
History
ARTICLE ABSTRACT
Purpose: One of the main reasons for cancer treatment resistance is the existence of cancer stem-like cells (CSCs). Here, we elucidated the relationship between low proteasome activity cells (LPACs) and CSCs.Experimental Design: The human colorectal cancer cell lines HCT116, SW480, DLD1, and KM12SM were engineered to stably express a green fluorescent molecule fused to the degron of ornithine decarboxylase, resulting in an accumulation of the fluorescence in LPACs. LPACs were isolated by flow cytometry. Treatment resistance (radio- and chemotherapy) and the capacity of LPACs to act as CSCs were analyzed. Microarray analysis was performed to reveal genes related to treatment resistance. The prognostic impact of potent genes was examined in 190 patients with colorectal cancer.Results: LPACs had a significantly increased capacity for radioresistance and chemoresistance (5-fluorouracil and oxaliplatin), significantly lower reactive oxygen species activity, and significantly increased sphere formation capacity compared with non-LPACs. The number of cells in the G0–G1 phase was significantly higher among LPACs. Subcutaneous injection of as few as 20 LPACs led to tumor formation in immunologically incompetent mice. Microarray analysis revealed that the expression of EP300-interacting inhibitor of differentiation 3 (EID3) was significantly increased in LPACs. In vitro assay revealed that EID3 positively controlled cell proliferation and treatment resistance. The high expression of EID3 was an adverse prognostic indicator in patients with colorectal cancer (P = 0.0400).Conclusions: LPACs have characteristic treatment resistance and act as CSCs in colorectal cancer. In addition, EID3 is one of the potential regulators of treatment resistance in colorectal cancer and may be a potential therapeutic target. Clin Cancer Res; 22(21); 5277–86. ©2016 AACR.
