Altered expression of LINC-ROR in cancer cell lines and tissues.

According to GLOBOCAN 2012, the worldwide burden of cancer increased and is expected to worsen within the next decades. Therefore, universal combat against cancer will not succeed with treatment solely; effective prevention and early detection are urgently needed to tackle the cancer crisis. Emerging data demonstrate that long non-coding RNAs are involved in numerous biological and pathological processes like development and differentiation and in a variety of human diseases including cancer. Located at 18q21, LINC-ROR (regulator of reprogramming) is a modulator of ESCs maintenance and hypoxia-signaling pathways in hepatocellular cancer cells. The aim of this study was to examine the expression of LINC-ROR in various cell lines and representative samples of human cancers by quantitative real-time RT-PCR to provide a snapshot on how LINC-ROR expression may be deregulated in cancer. More than 30 cell lines and 112 patient specimens from various tissues were assessed for relative expression of LINC-ROR. Our results revealed that the expression of LINC-ROR was lower in all somatic cancer cell lines compared to stem cells or cells with stem cell-like capabilities, like the embryonic carcinoma cell line, NTERA-2. In tissues, expression patterns vary, but some cancerous tissues displayed increased LINC-ROR expression compared to corresponding normal tissues. Thus, we hypothesize that LINC-ROR may have a key function in a subpopulation of cells from the tumor bulk, i.e., the cancer stem cells associated with specific properties including resistance to adverse environmental conditions.