Single-cell multiomic analysis identifies a HOX-PBX gene network regulating the survival of lymphangioleiomyomatosis cells

Sci Adv. 2023 May 10;9(19):eadf8549. doi: 10.1126/sciadv.adf8549. Epub 2023 May 10.

Abstract

Lymphangioleiomyomatosis (LAM) is a rare, progressive lung disease that predominantly affects women. LAM cells carry TSC1/TSC2 mutations, causing mTORC1 hyperactivation and uncontrolled cell growth. mTORC1 inhibitors stabilize lung function; however, sustained efficacy requires long-term administration, and some patients fail to tolerate or respond to therapy. Although the genetic basis of LAM is known, mechanisms underlying LAM pathogenesis remain elusive. We integrated single-cell RNA sequencing and single-nuclei ATAC-seq of LAM lungs to construct a gene regulatory network controlling the transcriptional program of LAM cells. We identified activation of uterine-specific HOX-PBX transcriptional programs in pulmonary LAMCORE cells as regulators of cell survival depending upon HOXD11-PBX1 dimerization. Accordingly, blockage of HOXD11-PBX1 dimerization by HXR9 suppressed LAM cell survival in vitro and in vivo. PBX1 regulated STAT1/3, increased the expression of antiapoptotic genes, and promoted LAM cell survival in vitro. The HOX-PBX gene network provides promising targets for treatment of LAM/TSC mTORC1-hyperactive cancers.

MeSH terms

  • Animals
  • Female
  • Gene Regulatory Networks*
  • Homeodomain Proteins*
  • Humans
  • Lung / metabolism
  • Lung / pathology
  • Lymphangioleiomyomatosis* / metabolism
  • Lymphangioleiomyomatosis* / pathology
  • Multiomics
  • Neoplasm Metastasis
  • Rats
  • Single-Cell Analysis
  • Transcription Factors / metabolism

Substances

  • Homeodomain Proteins
  • Transcription Factors