LncRNA SNHG7 sponges miR-216b to promote proliferation and liver metastasis of colorectal cancer through upregulating GALNT1

Abstract

Accumulating evidence suggests long noncoding RNAs (lncRNAs) play an important role in cancer progression. However, the function of lncRNA SNHG7 in colorectal cancer (CRC) remains unclear. In this study, SNHG7 expression was significantly upregulated in CRC tissues, especially in aggressive cases. In accordance, high level of SNHG7 was observed in CRC cell lines compared to normal colon cells. Furthermore, SNHG7 overexpression promoted the proliferation, migration, and invasion of CRC cell lines, while SNHG7 depletion inhibited invasion and cell viability in vitro. Mechanistically, knockdown of SNHG7 inhibited GALNT1 and EMT markers (E-cadherin and Vimentin). Importantly, SNHG7 directly interacted with miR-216b and downregulation of miR-216b reversed efficiently the suppression of GALNT1 induced by SNHG7 siRNA. Moreover, overexpression of SNHG7 significantly enhanced the tumorigenesis and liver metastasis of SW480 cells in vivo. SNHG7 positively regulated GALNT1 level through sponging miR-216b, and played an oncogenic role in CRC progression. Together, our study elucidated the role of SNHG7 as an miRNA sponge in CRC, and shed new light on lncRNA-directed diagnostics and therapeutics in CRC.

Long non‐coding small nucleolar RNA host genes in digestive cancers

“…In the cytoplasm, SNHG6 sponged MIR760 and upregulated its target gene FOXC1 to promote colon cancer cell proliferation, migration and invasion . SNHG7 was located in the cell cytoplasm in colon cancer and was highly expressed in colon cancer tissues . Although several mRNAs, including B3GLCT , FUT2 , MFNG , MGAT4A , GALNT1 , GALNT5 , GALNT7 , ST3GAL5 , and ST6GALNAC2 were related, GALNT7 was the most commonly associated with SNHG7 .…”

“…Some SNHGs can act as sponges of microRNAs to inhibit the roles of microRNAs in tumorigenesis and affect tumor progression. 23,31,32 On the other hand, they can also bind proteins to influence target genes or impact tumorigenesis via different signaling pathways, including the EMT, Wnt, PIK3CA, NF-κB, and TP53 signaling pathways. [33][34][35] Moreover, the relationship with transcriptional activation also participates in the progression.…”

“…53 SNHG7 also could sponge MIR216B, to increase GALNT1 and activate EMT to promote colorectal cancer cell migration and invasion. 32 Wang et al put forward that SNHG12 augmented colon cancer proliferation, cell cycle progression and inhibited apoptosis by inhibiting the related proteins CDK4, CDK6 and CCND1, and suppressing CASP3. 54 Shorter overall survival rate and disease-free survival rate were correlated with higher DANCR expression.…”

SMAD3/SP1 complex‐mediated constitutive active loop between lncRNA PCAT7 and TGF‐β signaling promotes prostate cancer bone metastasis

“…Previous studies have revealed that cytoplasmic lncRNAs generally function as ceRNAs to regulate mRNA expression via sponging versatile miRNAs, thereby playing a pivotal role in cancer metastasis (Lian et al , ; Shan et al , ; Sun et al , ; Wang and Kong, ; Yan et al , ). In fact, lncRNAs exert their functions in several biological processes via interaction with DNA, proteins, and RNAs, which is dependent on the subcellular localization of the lncRNAs within the cells to a large extent (Chen et al , ).…”

In silico analysis of long non-coding RNAs in medulloblastoma and its subgroups

“…Although the precise roles of the vast majority of identified or predicted lncRNAs remain unknown [14], they are increasingly recognized as being involved in cis or trans interactions regulating gene expression in the nucleus and protein interactions in the nucleus and cytoplasm. Some of the functionally diverse roles of lncRNAs include transcriptional silencing (e.g., XIST [15]), enhancers by regulating three-dimensional chromosomal structure to strengthen interactions between enhancers and promoters (e.g., LUNAR1 [16]), and as microRNA sponges that sequester microRNAs from their target sites (e.g., SNHG7 [17]). LncRNAs can also act as scaffolds for protein-protein and protein-nucleic acid interactions [18].…”