1. Academic Validation
  2. CRISPR screens identify a novel combination treatment targeting BCL-XL and WNT signaling for KRAS/BRAF-mutated colorectal cancers

CRISPR screens identify a novel combination treatment targeting BCL-XL and WNT signaling for KRAS/BRAF-mutated colorectal cancers

  • Oncogene. 2021 May;40(18):3287-3302. doi: 10.1038/s41388-021-01777-7.
Hae Rim Jung  # 1 2 Yumi Oh  # 1 2 Deukchae Na 3 Seoyeon Min 4 Jinjoo Kang 4 Dongjun Jang 5 Seungjae Shin 5 Jiwon Kim 5 Sang Eun Lee 5 Eui Man Jeong 6 7 8 9 Joon Yong An 10 Chang Ohk Sung 11 Won-Suk Lee 12 Charles Lee 4 13 Sung-Yup Cho 14 15 16
Affiliations

Affiliations

  • 1 Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul, Korea.
  • 2 Medical Research Center, Genomic Medicine Institute, Seoul National University College of Medicine, Seoul, Korea.
  • 3 Ewha Institute of Convergence Medicine, Ewha Womans University Mokdong Hospital, Seoul, Korea.
  • 4 Department of Life Science, Ewha Womans University, Seoul, Korea.
  • 5 Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea.
  • 6 Department of Pharmacy, College of Pharmacy, Jeju National University, Jeju Special Self-Governing Province, Korea.
  • 7 Interdisciplinary Graduate Program in Advanced Convergence Technology and Science, Jeju National University, Jeju Special Self-Governing Province, Korea.
  • 8 Bio-Health Materials Core-Facility Center, Jeju National University, Jeju Special Self-Governing Province, Korea.
  • 9 Practical Translational Research Center, Jeju National University, Jeju Special Self-Governing Province, Korea.
  • 10 School of Biosystem and Biomedical Science, College of Health Science, Korea University, Seoul, Korea.
  • 11 Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
  • 12 Department of Surgery, Gil Medical Center, Gachon University, Incheon, Korea.
  • 13 The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA.
  • 14 Medical Research Center, Genomic Medicine Institute, Seoul National University College of Medicine, Seoul, Korea. csybio@snu.ac.kr.
  • 15 Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea. csybio@snu.ac.kr.
  • 16 Cancer Research Institute, Seoul National University, Seoul, Korea. csybio@snu.ac.kr.
  • # Contributed equally.
Abstract

Metastatic or recurrent colorectal Cancer (CRC) patients require systemic chemotherapy, but the therapeutic options of targeted agents remain limited. CRC patients with KRAS or BRaf gene mutations exhibit a worse prognosis and are resistant to anti-EGFR treatment. Previous studies have shown that the expression of anti-apoptotic protein BCL-XL is increased in CRC patients with KRAS/BRaf mutations, suggesting BCL-XL as a therapeutic target for this subgroup. Here, we performed genome-wide CRISPR/Cas9 screens of cell lines with KRAS mutations to investigate the factors required for sensitivity to BCL-XL inhibitor ABT-263 using single-guide RNAs (sgRNAs) that induce loss-of-function mutations. In the presence of ABT-263, sgRNAs targeting negative regulators of Wnt signaling (resulting in Wnt activation) were enriched, whereas sgRNAs targeting positive regulators of Wnt signaling (resulting in Wnt inhibition) were depleted in ABT-263-resistant cells. The activation of Wnt signaling was highly associated with an increased expression ratio of anti- to pro-apoptotic Bcl-2 Family genes in CRC samples. Genetic and pharmacologic inhibition of Wnt signaling using β-catenin short hairpin RNA or TNIK inhibitor NCB-0846, respectively, augmented ABT-263-induced cell death in KRAS/BRAF-mutated cells. Inhibition of Wnt signaling resulted in transcriptional repression of the anti-apoptotic Bcl-2 Family member, MCL1, via the functional inhibition of the β-catenin-containing complex at the MCL1 promoter. In addition, the combination of ABT-263 and NCB-0846 exhibited synergistic effects in in vivo patient-derived xenograft (PDX) models with KRAS mutations. Our data provide a novel targeted combination treatment strategy for the CRC patient subgroup with KRAS or BRaf mutations.

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Products
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    Product Name
    Description
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  • HY-100830
    99.61%, TRAF2- and NCK-interacting Inhibitor