1. Academic Validation
  2. LINC00115 promotes chemoresistant breast cancer stem-like cell stemness and metastasis through SETDB1/PLK3/HIF1α signaling

LINC00115 promotes chemoresistant breast cancer stem-like cell stemness and metastasis through SETDB1/PLK3/HIF1α signaling

  • Mol Cancer. 2024 Mar 22;23(1):60. doi: 10.1186/s12943-024-01975-3.
Fei Luo # 1 Mingda Zhang # 1 Bowen Sun # 1 Chenxin Xu 1 Yi Yang 2 Yingwen Zhang 1 Shanshan Li 2 Guoyu Chen 1 Ceshi Chen 3 Yanxin Li 4 Haizhong Feng 5
Affiliations

Affiliations

  • 1 State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China.
  • 2 Pediatric Translational Medicine Institute, Department of Hematology & Oncology, Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, National Health Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai, 200127, China.
  • 3 Academy of Biomedical Engineering, the Third Affiliated Hospital, Kunming Medical University, Kunming, 650500, China. chenc@kmmu.edu.cn.
  • 4 Pediatric Translational Medicine Institute, Department of Hematology & Oncology, Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, National Health Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai, 200127, China. liyanxincau@163.com.
  • 5 State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China. fenghaizhong@sjtu.edu.cn.
  • # Contributed equally.
Abstract

Background: Cancer stem-like cell is a key barrier for therapeutic resistance and metastasis in various cancers, including breast Cancer, yet the underlying mechanisms are still elusive. Through a genome-wide lncRNA expression profiling, we identified that LINC00115 is robustly upregulated in chemoresistant breast Cancer stem-like cells (BCSCs).

Methods: LncRNA microarray assay was performed to document abundance changes of lncRNAs in paclitaxel (PTX)-resistant MDA-MB-231 BCSC (ALDH+) and non-BCSC (ALDH-). RNA pull-down and RNA immunoprecipitation (RIP) assays were performed to determine the binding proteins of LINC00115. The clinical significance of the LINC00115 pathway was examined in TNBC metastatic lymph node tissues. The biological function of LINC00115 was investigated through gain- and loss-of-function studies. The molecular mechanism was explored through RNA sequencing, mass spectrometry, and the CRISPR/Cas9-knockout system. The therapeutic potential of LINC00115 was examined through xenograft animal models.

Results: LINC00115 functions as a scaffold lncRNA to link SETDB1 and PLK3, leading to enhanced SETDB1 methylation of PLK3 at both K106 and K200 in drug-resistant BCSC. PLK3 methylation decreases PLK3 phosphorylation of HIF1α and thereby increases HIF1α stability. HIF1α, in turn, upregulates ALKBH5 to reduce m6A modification of LINC00115, resulting in attenuated degradation of YTHDF2-dependent m6A-modified RNA and enhanced LINC00115 stability. Thus, this positive feedback loop provokes BCSC phenotypes and enhances chemoresistance and metastasis in triple-negative breast Cancer. SETDB1 inhibitor TTD-IN with LINC00115 ASO sensitizes PTX-resistant cell response to chemotherapy in a xenograft animal model. Correlative expression of LINC00115, methylation PLK3, SETDB1, and HIF1α are prognostic for clinical triple-negative breast cancers.

Conclusions: Our findings uncover LINC00115 as a critical regulator of BCSC and highlight targeting LINC00115 and SETDB1 as a potential therapeutic strategy for chemotherapeutic resistant breast Cancer.

Keywords

Cancer stem-like cells; HIF1α; LINC00115; Lysine methylation; Therapeutic resistance; Triple-negative breast cancer.

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