Decoding the lncRNAome Across Diverse Cellular Stresses Reveals Core p53-effector Pan-cancer Suppressive lncRNAs

Ramkrishna Mitra1, Clare M Adams1, Christine M Eischen1

  • 1Department of Pharmacology, Physiology, and Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania.

PubMed

Insights

Researchers identified core long non-coding RNAs (lncRNAs) regulated by p53 that suppress tumors across various cancers and cell types. These p53-targeted lncRNAs impact cancer cell growth and patient survival.

Area of Science:

  • Genomics
  • Cancer Biology
  • Molecular Oncology

Background:

  • Long non-coding RNAs (lncRNAs) play roles in cancer, but their regulation and function are often unknown.
  • The tumor suppressor p53 is a critical regulator in cancer, but its direct transcriptional targets, including lncRNAs, are not fully characterized.

Purpose of the Study:

  • To identify and characterize core p53-regulated lncRNAs across multiple cancer types.
  • To investigate the functional roles of these lncRNAs in tumor suppression and their association with patient survival.

Main Methods:

  • Integrated computational and experimental approaches, including pan-cancer RNAi/CRISPR screens, genomic, epigenetic, and expression profiles (single-cell RNA sequencing).
  • Analysis of p53-dependent transcriptional regulation under various cellular stresses.
  • Experimental validation using independent datasets, patient cohorts, and cell-based assays.

Main Results:

  • Identified a set of core lncRNAs directly transactivated by p53 across diverse cancer types and cellular stresses.
  • These lncRNAs consistently suppressed cancer cell survival and growth and were associated with improved patient survival.
  • A specific lncRNA, PTSL, was found to inhibit proliferation and induce G2 cell-cycle arrest by modulating the G2 regulatory network.

Conclusions:

  • Elucidated previously unknown, high-confidence p53-targeted lncRNAs that function as tumor suppressors.
  • Revealed the role of these lncRNAs in the p53-mediated cell-cycle regulation and their impact on cancer progression and patient outcomes.

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