HOXB7 overexpression in lung cancer is a hallmark of acquired stem-like phenotype

Oncogene. 2018 Jun;37(26):3575-3588. doi: 10.1038/s41388-018-0229-9. Epub 2018 Mar 26.

Abstract

HOXB7 is a homeodomain (HOX) transcription factor involved in regional body patterning of invertebrates and vertebrates. We previously identified HOXB7 within a ten-gene prognostic signature for lung adenocarcinoma, where increased expression of HOXB7 was associated with poor prognosis. This raises the question of how HOXB7 overexpression can influence the metastatic behavior of lung adenocarcinoma. Here, we analyzed publicly available microarray and RNA-seq lung cancer expression datasets and found that HOXB7-overexpressing tumors are enriched in gene signatures characterizing adult and embryonic stem cells (SC), and induced pluripotent stem cells (iPSC). Experimentally, we found that HOXB7 upregulates several canonical SC/iPSC markers and sustains the expansion of a subpopulation of cells with SC characteristics, through modulation of LIN28B, an emerging cancer gene and pluripotency factor, which we discovered to be a direct target of HOXB7. We validated this new circuit by showing that HOXB7 enhances reprogramming to iPSC with comparable efficiency to LIN28B or its target c-MYC, which is a canonical reprogramming factor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma of Lung / genetics
  • Adenocarcinoma of Lung / pathology*
  • Cell Line, Tumor
  • Cell Movement
  • Cell Proliferation
  • Embryonic Stem Cells / metabolism*
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic / genetics
  • HEK293 Cells
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • Humans
  • Induced Pluripotent Stem Cells / metabolism*
  • Lung Neoplasms / genetics
  • Lung Neoplasms / pathology*
  • Neoplastic Stem Cells / pathology*
  • Proto-Oncogene Proteins c-myc / metabolism
  • RNA Interference
  • RNA, Small Interfering / genetics
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism*

Substances

  • HOXB7 protein, human
  • Homeodomain Proteins
  • LIN28B protein, human
  • MYC protein, human
  • Proto-Oncogene Proteins c-myc
  • RNA, Small Interfering
  • RNA-Binding Proteins