A Review on the Role of Small Nucleolar RNA Host Gene 6 Long Non-coding RNAs in the Carcinogenic Processes

Being located on 17q25.1, small nucleolar RNA host gene 6 (SNHG16) is a member of SNHG family of long non-coding RNAs (lncRNA) with 4 exons and 13 splice variants. This lncRNA serves as a sponge for a variety of miRNAs, namely miR-520a-3p, miR-4500, miR-146a miR-16–5p, miR-98, let-7a-5p, hsa-miR-93, miR-17-5p, miR-186, miR-302a-3p, miR-605-3p, miR-140-5p, miR-195, let-7b-5p, miR-16, miR-340, miR-1301, miR-205, miR-488, miR-1285-3p, miR-146a-5p, and miR-124-3p. This lncRNA can affect activity of TGF-β1/SMAD5, mTOR, NF-κB, Wnt, RAS/RAF/MEK/ERK and PI3K/AKT pathways. Almost all studies have reported oncogenic effect of SNHG16 in diverse cell types. Here, we explain the results of studies about the oncogenic role of SNHG16 according to three distinct sets of evidence, i.e., in vitro, animal, and clinical evidence.

Long Non-coding RNA Small Nucleolar RNA Host Gene 14, a Promising Biomarker and Therapeutic Target in Malignancy

Small nucleolar RNA host gene 14 (SNHG14) is a long non-coding RNA found to be overexpressed in various types of cancers. Moreover, the expression level of SNHG14 was closely associated with multiple clinicopathological characteristics such as prognosis, tumor differentiation, TNM stage, and lymph node metastasis. Functionally, gain- and loss-of-function of SNHG14 revealed that overexpressed SNHG14 promoted cancer cell viability, invasion, and migration, whereas its down-regulation produced the opposite effect. Mechanistically, regulating its target gene expression by sponging distinct miRNAs might be the major mechanism underlying the oncogenic functions of SNHG14. Thus, SNHG14 might be a promising prognostic biomarker and therapeutic target for cancers. In this review, we discuss the expression profile, biological function, and molecular mechanisms of SNHG14 in cancers to provide a molecular basis for the clinical utility of SNHG14 in the future.

Long Noncoding RNA Small Nucleolar RNA Host Gene 6 Promotes Cell Proliferation, Migration and Invasion in Melanoma by Sponging miR-944

Long noncoding RNA small nucleolar RNA host gene 6 (SNHG6) has been reported to be a tumor promoter in various human cancers. Nevertheless, the detailed functions and clinical value of SNHG6 in melanoma remain elusive. The study aimed to investigate the role and potential mechanism of SNHG6 in melanoma metastasis. Quantitative real-time PCR (qRT-PCR) was used to detect the expressions of SNHG6 and miR-944 in melanoma cells. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8) assay, and cell migration and invasion were measured by wound healing assay and cell invasion assay, respectively. In addition, dual luciferase reporter assay was performed to verify the interaction between SNHG6 and miR-944. The protein expressions of PI3K/Akt pathway were evaluated by western blot assay. The results revealed that SNHG6 expression was significantly increased in melanoma cells. Knockdown of SNHG6 suppressed cell proliferation, migration and invasion in A375 cells. Moreover, miR-944 was identified as a direct target of SNHG6 in melanoma. miR-944 was downregulated in melanoma cells, while SNHG6 silencing improved miR-944 level in A375 cells. Rescue experiments demonstrated that miR-944 overexpression reversed the effects of SNHG6 on A375 cell proliferation, migration and invasion. Altogether, SNHG6 exerted oncogenic effects in melanoma cells, providing a novel promising target for the treatment of melanoma.