The value of lncRNA FENDRR and FOXF1 as a prognostic factor for survival of lung adenocarcinoma

// Antonio Herrera 1, 2, * , Marta Cuadros 1, 3, * , Maria Isabel Rodriguez 1, 2 , Sandra Rodriguez 4 , Raul Torres 4 , Marcos Estecio 5 , Isabel F. Coira 1, 2 , Claudia Loidi 6 , Monica Saiz 6 , Pedro Carmona-Saez 1 and Pedro P. Medina 1, 2 1 Centre for Genomics and Oncological Research, PTS Granada, Centro Pfizer - Universidad de Granada - Junta de Andalucia de Genomica e Investigacion Oncologica (GENYO), Granada, Spain 2 Department of Biochemistry and Molecular Biology I, University of Granada, Granada, Spain 3 Department of Biochemistry and Molecular Biology III e Immunology, University of Granada, Granada, Spain 4 Molecular Cytogenetics Group, Human Cancer Genetics Program, Spanish National Cancer Research Centre-CNIO, Madrid, Spain 5 Department of Epigenetics and Molecular Carcinogenesis, UT MD Anderson Cancer Center, Houston, TX, USA 6 Pathological Anatomy, Universitary Hospital Cruces, University of Pais Vasco, Spain * These authors have contributed equally to this work Correspondence to: Pedro P. Medina, email: pedromedina@ugr.es Keywords: lncRNA; FENDRR; FOXF1; lung cancer; methylation Received: June 09, 2017      Accepted: October 02, 2017      Published: October 27, 2017 ABSTRACT It is increasingly evident that non-coding RNAs play a significant role in tumour development. However, we still have a limited knowledge of the clinical significance of long non-coding RNAs (lncRNAs) in lung cancer. The FENDRR is a long coding RNA (also named FOXF1-AS1 ) located in the vicinity of the protein-coding gene FOXF1 at 16q24.1 chromosomal region. The present study aimed to define the clinic pathological significance of the long-non-coding RNA FENDRR in lung adenocarcinomas. FENDRR expression measured by quantitative PCR was found significantly downregulated (p<0.001) in lung adenocarcinoma samples in comparison with their normal adjacent tissues (n=70). RNA in situ hybridization (RNA-FISH) corroborated independently the down-regulation of FENDRR . Interestingly, the expression of FENDRR correlated positively (p<0.001) with the expression of its protein-coding neighbor gene FOXF1 . Additionally, FOXF1 expression was also found downregulated in adenocarcinomas compared to normal samples (p<0.001) and its expression was significantly correlated with overall survival alone (p=0.003) or in combination with FENDRR expression (p=0.01). In conclusion, our data support that FENDRR and FOXF1 expression is decreased in lung adenocarcinoma and should be considered as new potential diagnostic/prognosis biomarkers.