An integrated microfluidic system for screening of peptides specific to colon cancer cells and colon cancer stem cells using the phage display technology

The Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by replicating selected results from a substantial number of high-profile papers in the field of cancer biology. The papers, which were published between 2010 and 2012, were selected on the basis of citations and Altmetric scores (<xref ref-type="bibr" rid="bib5">Errington et al., 2014</xref>). This Registered report describes the proposed replication plan of key experiments from ‘Wnt activity defines colon cancer stem cells and is regulated by the microenvironment’ by Vermeulen and colleagues, published in Nature Cell Biology in 2010 (<xref ref-type="bibr" rid="bib20">Vermeulen et al., 2010</xref>). The key experiments that will be replicated are those reported in Figures 2F, 6D, and 7E. In these experiments, Vermeulen and colleagues utilize a reporter for Wnt activity and show that colon cancer cells with high levels of Wnt activity also express cancer stem cell markers (Figure 2F; <xref ref-type="bibr" rid="bib20">Vermeulen et al., 2010</xref>). Additionally, treatment either with conditioned medium derived from myofibroblasts or with hepatocyte growth factor restored clonogenic potential in low Wnt activity colon cancer cells in vitro (Figure 6D; <xref ref-type="bibr" rid="bib20">Vermeulen et al., 2010</xref>) and in vivo (Figure 7E; <xref ref-type="bibr" rid="bib20">Vermeulen et al., 2010</xref>). The Reproducibility Project: Cancer Biology is a collaboration between the Center for Open Science and Science Exchange and the results of the replications will be published in eLife.

Download Full-text

E2F7 Transcriptionally Inhibits MicroRNA-199b Expression to Promote USP47, Thereby Enhancing Colon Cancer Tumor Stem Cell Activity and Promoting the Occurrence of Colon Cancer

Frontiers in Oncology ◽

10.3389/fonc.2020.565449 ◽

2021 ◽

Vol 10 ◽

Author(s):

Xiong Guo ◽

Ling Liu ◽

Qi Zhang ◽

Weiming Yang ◽

Yang Zhang

Keyword(s):

Stem Cells ◽

Colon Cancer ◽

Cancer Stem Cells ◽

Cancer Cells ◽

Cell Activity ◽

Luciferase Reporter ◽

Tumor Stem Cell ◽

Colon Cancer Cells ◽

Loss Of Function ◽

Colon Cancer Stem Cells

microRNAs (miRNAs) can modulate the expression level of genes in a post-transcription manner, which are closely related to growth and metastasis of colon cancer. Herein, we aimed to explore how miR-199b influences colon cancer and to characterize its underlying molecular mechanism associating with E2F transcription factor 7 (E2F7). Assays of RT-qPCR, Western blot, and immunohistochemistry were utilized to detect the expression of E2F7 in the tissue samples collected from 30 patients diagnosed with colon cancer. Flow analysis was utilized to detect the ratio of ALDH1+ and CD133+ colon cancer stem cells. The interaction between E2F7, miR-199b, USP47, and MAPK was identified by ChIP-Seq analysis, luciferase reporter, RNA pull-down, co-immunoprecipitation, as well as glutathione-S-transferase (GST) pull-down experiments. Based on the gain- and loss-of-function approaches, the cellular functions of colon cancer cells by the E2F7-regulated miR-199b/USP47/MAPK axis were assessed. It was identified that E2F7 are expressed highly in the collected colon cancer tissues. E2F7 silencing reduced the production of ALDH1+ and CD133+ colon cancer stem cells and antagonized the effects of 5-fluorouracil (5-FU) treatment. Besides, the silencing of E2F7 was observed to suppress the oxidative stress, proliferation, migration, as well as invasion of ALDH1+ cells in vitro and tumorigenesis of colon cancer cells in vivo. Our findings reveal the pro-oncogenic effect of E2F7 on colon cancer development, highlighting E2F7 as a novel target for therapeutic strategy for colon cancer.

Download Full-text