title: HOXB2, an adverse prognostic indicator for stage I lung adenocarcinomas, promotes invasion by transcriptional regulation of metastasis-related genes in HOP-62 non-small cell lung cancer cells.
abstract: BACKGROUND
  Previously, using microarray and real-time RT-PCR analysis, we established that HOXB2 is an adverse prognostic indicator for Stage I lung adenocarcinomas. HOXB2 is one of the homeobox master development-controlling genes regulating morphogenesis and cell differentiation.
  
  
  METHODS
  The molecular functions of HOXB2 were analyzed with a small interfering RNA (siRNA) approach in HOP-62 human non-small cell lung cancer (NSCLC) cells featuring high HOXB2 expression. Matrigel invasion assays and microarray gene expression analysis were compared between the HOXB2-siRNA cells and the control cells.
  
  
  RESULTS
  The Matrigel invasion assays showed attenuation of HOXB2 expression by siRNA to result in a significant decrease of invasiveness compared to the control cells (p = 0.0013, paired t-test). On microarray gene expression analysis, up-regulation of many metastasis-related genes and others correlating with HOXB2 expression was observed in the control case. With attenuation of HOXB2 expression, downregulation was noted for laminins alpha 4 and 5, involved in enriched signaling, and for Mac-2BP (Mac-2 binding protein) and integrin beta 4 amongst the genes having an enriched glycoprotein ontology.
  
  
  CONCLUSIONS
  HOXB2 promotes invasion of lung cancer cells through the regulation of metastasis-related genes.
authors.affiliation: Department of Pathology, The Cancer Institute, Japanese Foundation for Cancer Research (JFCR), Koto-ku, Tokyo, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Inamura
authors.forename: Yuki
authors.initials: Y
authors.lastname: Togashi
authors.forename: Hironori
authors.initials: H
authors.lastname: Ninomiya
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimoji
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Noda
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ishikawa