Long Noncoding RNA ANROC on the INK4 Locus Functions to Suppress Cell Proliferation

Abstract

Background/Aim: The INK4 locus encodes three important genes p15INK4B, p16INK4A, and ARF, which function to suppress oncogenesis, and a long noncoding RNA, ANRIL, which, in contrast, functions to promote oncogenesis. Herein, we report a fifth genetic element on the INK4 locus, a long noncoding RNA with unknown function named associated negative regulation of cell proliferation (ANROC), which played a role in the suppression of cell proliferation. Materials and Methods: Following ANROC silencing in cells by siRNA, quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and cell cycle analysis using flow cytometry were performed. Results: ANROC expression was decreased by oncogenic RAS signalling. ANROC knockdown enhanced HeLa cell proliferation and induced cyclin B1 mRNA, which promotes G2/M progression of the cell cycle. Furthermore, flow cytometric analysis revealed that ANROC knockdown increased the percentage of cells in the S and G2/M phases of the cell cycle. Conclusion: ANROC functions to suppress cell cycle progression by suppressing cyclin B1 expression, thus inhibiting cell proliferation.