Illuminating the role of lncRNAs ROR and MALAT1 in cancer stemness state of anaplastic thyroid cancer: An exploratory study

BACKGROUND: Anaplastic thyroid cancer (ATC) is one of the most aggressive malignancies in humans that accounts for a considerable rate of cancer-associated mortality. Since conventional therapies are lacking sufficient efficacy, new treatment approaches are required. This goal could be achieved through a better understanding of the molecular pathogenesis of ATC. Thyroid tumorigenesis is initiated by a subpopulation of cells known as cancer stem cells (CSCs) with specific markers such as CD133 that confers to processes such as self-renewal and metastasis. Besides, some long non-coding RNAs (lncRNAs) promote tumorigenesis by mediating the aforementioned processes. METHODS: Here, we designed an exploratory study to investigate the role of lncRNAs ROR and MALAT1 and their related genes in CSC stemness. Using magnetic-activated cell sorting (MACS), the CD133(-) and CD133(+) subpopulations were separated in SW1736 and C643 ATC cell lines. Next, the expression profiles of the CD133 marker, MALAT1, and its associated genes (CCND1, NESTIN, MYBL2, MCL1, IQGAP1), as well as ROR and its related genes (POU5F1, SOX2, NANOG), were explored by qRT-PCR. RESULTS: We found significant up-regulation of ROR, POU5F1, SOX2, NANOG, CD133, MALAT1, IQGAP1, and MCL1 in CD133(+) SW1736 cells compared to CD133(-) cells. As for CD133(+) C643 cells, CCND1, IQGAP1, POU5F1, SOX2, NANOG, and NESTIN were significantly up-regulated compared to CD133(-) cells. CONCLUSIONS: This study suggests that these lncRNAs in CD133-positive SW1736 and C643 cells might regulate stemness behaviors in ATC.