SNHG6 Promotes Tumor Growth via Repression of P21 in Colorectal Cancer

Background/Aims: SNHG6 (Small Nucleolar RNA Host Gene 6) is a novel non-coding RNA (ncRNA) and its cellular function is largely unknown. Methods: Cell Counting Kit-8 (CCK-8) cell growth assay, colony formation and flow cytometry were used to determine colorectal cancer cell proliferation, cell cycle progression and apoptosis in vitro. The xenograft tumor formation assay in nude mice was established to evaluate tumor growth in vivo. RNA immunopreciptation (RIP) analysis was performed to examine whether SNHG6 could bind to EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit), and chromatin immunoprecipitation (ChIP) assay was conducted to examine whether SNHG6 could repress p21 transcription by recruiting EZH2 to the p21 promoter. Results: Here we found that SNHG6 was upregulated and its expression levels were positively correlated with advanced tumor stage in colorectal cancer. Survival analysis suggested that higher expression of SNHG6 predicted poor prognosis in patients with colorectal cancer. Functional studies indicated that SNHG6 could promote cell proliferation via a direct suppression of p21 expression in colorectal cancer cells. Moreover, SNHG6 repressed p21 transcription through recruiting EZH2 to the p21 promoter in colorectal cancer cells. Conclusion: Taken together, our study demonstrates that SNHG6 promotes tumor growth via repression of p21 in colorectal cancer, which may provide a promising target for novel anticancer therapeutics. (c) 2018 The Author(s) Published by S. Karger AG, Basel