The lncRNA ESCCAL-1 expression in ESCC. (A) UCSC genome browser view of ESCCAL-1 (chr8:76139826-76139767). This lncRNA is also known as RP11-697M17.1 from GENCODE transcript annotation or ENST00000504531.2 or CASC9 (cancer susceptibility candidate 9) from Refseq annotation. The transcriptional regulation of ESCCAL-1/CASC9 has been evaluated by ENCODE (detailed seen Additional file 3: Figure S2). (B) ESCCAL-1 expression was further examined in independent 26 pair-matched normal and ESCC samples, its expression was significantly higher in 17 out of 26 (65%) ESCC samples relative to normal tissue. LncRNA HOTAIR, a known oncogenic lncRNA was also measured as a positive control.