Volume 26, Issue 3, Pages 744-754 (March 2018) miR-145 Antagonizes SNAI1-Mediated Stemness and Radiation Resistance in Colorectal Cancer  Yun Zhu, Cindy Wang, Scott A. Becker, Katie Hurst, Lourdes M. Nogueira, Victoria J. Findlay, E. Ramsay Camp  Molecular Therapy  Volume 26, Issue 3, Pages 744-754 (March 2018) DOI: 10.1016/j.ymthe.2017.12.023 Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions

Figure 1 Elevated SNAI1 Expression in Human Colorectal Cancer Datasets Whole exome and RNA Seq data of colorectal adenocarcinoma from TCGA was mined for the frequency of SNAI1, SNAI2, ZEB1, and ZEB2 using bioportal.53 Molecular Therapy 2018 26, 744-754DOI: (10.1016/j.ymthe.2017.12.023) Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions

Figure 2 Ectopic Expression of SNAI1 Induces CSC Phenotype (A) Western blot analysis for expression of critical EMT mediators and CSC transcription factors in parental colon cancer cell lines. (B) Western blot analysis and relative density quantitation of EMT biomarker and stem-cell-related transcription factors in ectopic-expressing SNAI1 cell lines compared with empty vector control cells. (C and D) Limited dilution spheroid assay comparing DLD1-SNAI1 (C) and HCT116-SNAI1 (D) cells with empty vector (Vec) control cells (data are shown as mean ± SD; n = 12; * indicated p < 0.05). Molecular Therapy 2018 26, 744-754DOI: (10.1016/j.ymthe.2017.12.023) Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions

Figure 3 Ectopic Expression of SNAI1 Increases Resistance to Radiation Therapy (A) Clonogenic assay on DLD1-SNAI1 cells and vector control cells treated with increasing doses of radiation. (B) Ectopic SNAI1 expression enhanced cancer cell viability after radiation treatment (data are shown as mean ± SD; n = 3; * indicated as p < 0.05). Molecular Therapy 2018 26, 744-754DOI: (10.1016/j.ymthe.2017.12.023) Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions

Figure 4 SNAI1 Represses miR-145 Promoter Activity and Expression in Colorectal Cancer Cells (A) Relative miR-145 expression level assessed by real-time PCR in parental colorectal cancer cell lines: HCT116 cells versus other four colorectal cancer cell lines (data are shown as mean ± SD; n = 3; * indicated p < 0.05). (B and C) Relative miR-145 expression level of (B) DLD1-SNAI1 cells and (C) HCT116-SNAI1 cells compared to vector control cells (data are shown as mean ± SD; n = 3; * indicated p < 0.05). (D and E) Luciferase reporter activity of (D) DLD1-SNAI1 and (E) HCT116-SNAI1 cells compared to vector control cells (data are shown as mean ± SD; n = 3; *p < 0.05). Molecular Therapy 2018 26, 744-754DOI: (10.1016/j.ymthe.2017.12.023) Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions

Figure 5 miR-145 Sensitizes SNAI1-Overexpressing Colorectal Cancer Cells to Radiation Therapy (A and B) Clonogenic assay (A) and quantitation (B) following radiation of DLD1-SNAI1 cells after transfection of miR-145 compared with scr vector (data are shown as mean ± SD; n = 3; * indicated p < 0.05, DLD1-SNAI1/scr versus DLD1-Vec/scr; ** indicated p < 0.05, DLD1-SNAI1/miR-145 versus DLD1-SNAI1/scr). (C) Clonogenic assay following radiation of SW620 cells after transfection of miR-145 compared with scr control for 48 hr (data are shown as mean ± SD; n = 3; * indicated p < 0.05). (D) Limited dilution in vitro spheroid assay of SW620 cells after transfection of miR-145 compared with scr control for 48 hr (data are shown as mean ± SD; n = 6; * indicated p < 0.05). (E) Western blot analysis of EMT mediators and miR-145 targets in SW620 cells after transfection with miR-145 and scr control for 48 hr. Molecular Therapy 2018 26, 744-754DOI: (10.1016/j.ymthe.2017.12.023) Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions

Figure 6 SNAI1 and miR-145 Expression in CSC and Non-CSC Population in Patient-Derived Rectal Cancer Xenografts (A) Droplet digital PCR analysis of genes involved in the SNAI1:miR-145 axis. (B) miR-145 in FACS-sorted non-CSC (EpCAM+/ALDH−; black bars) and CSC (EpCAM+/ALDH+; gray bars) cells from two patient-derived rectal cancer xenografts (* indicated p < 0.05). Molecular Therapy 2018 26, 744-754DOI: (10.1016/j.ymthe.2017.12.023) Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions

Figure 7 Therapeutic Mechanism of miR-145 Delivery to Overcome SNAI1-Mediated Colorectal Cancer Radiation Resistance SNAI1 can activate Nanog and repress miR-145. Thus, SNAI1 mediates the CSC program, resulting in a radiation-resistant colorectal cancer cell population. Delivery of miR-145 to target multiple stemness genes, including Nanog, KLF4, and c-Myc, can impair CSC self-renewal capacity and increase sensitivity of radiation therapy. Molecular Therapy 2018 26, 744-754DOI: (10.1016/j.ymthe.2017.12.023) Copyright © 2018 The American Society of Gene and Cell Therapy Terms and Conditions