2627

GATA6

GATA binding protein 6;GATA6;GATA binding protein 6

GATA-binding factor 6|transcription factor GATA-6

18q11.1-q11.2

protein-coding

Liver metastasis is a major cause of mortality for colorectal cancer (CRC). However, the underlying mechanisms remain largely unknown. GATA binding protein 6 (GATA6), a zinc-finger transcription factor, is expressed in the colorectal epithelium. We investigated the clinical significance of GATA6 and its role in invasion and metastasis in CRC. expression of GATA6 in 89 cancerous, 35 adjacent normal and 39 liver metastatic samples from 89 CRC patients undergoing surgical resection was detected by immunohistochemical (IHC) methods. The effect of GATA6 on invasion and metastasis was assessed in CRC cells by shRNA lentivirus or expressed-plasmid transfection. We found that GATA6 expression was significantly higher in liver metastatic tissues compared with adjacent normal tissues. Aberrant GATA6 expression in CRC was associated with liver metastasis. Kaplan-Meier analysis showed GATA6 expression correlated with poor overall survival (OS) in CRC. The cell invasion and migration of established CRC cell lines were decreased by GATA6 knockdown and enhanced by GATA6 overexpression in vitro. Thus, aberrant expression of GATA6 correlates with poor prognosis and liver metastasis in CRC.

Molecular programs that mediate normal cell differentiation are required for oncogenesis and tumor cell survival in certain cancers. How cell-lineage-restricted genes specifically influence metastasis is poorly defined. In lung cancers, we uncovered a transcriptional program that is preferentially associated with distal airway epithelial differentiation and lung adenocarcinoma (ADC) progression. This program is regulated in part by the lineage transcription factors GATA6 and HOPX. These factors can cooperatively limit the metastatic competence of ADC cells, by modulating overlapping alveolar differentiation and invasogenic target genes. Thus, GATA6 and HOPX are critical nodes in a lineage-selective pathway that directly links effectors of airway epithelial specification to the inhibition of metastasis in the lung ADC subtype.