SNHG16 promotes tumorigenesis and cisplatin resistance by regulating miR-338-3p/PLK4 pathway in neuroblastoma cells

Abstract

Background Long noncoding RNA small nucleolar RNA host gene 16 (lncRNA SNHG16) has been revealed to be involved in the tumorigenesis of neuroblastoma. However, the role of SNHG16 in regulating cisplatin sensitivity in neuroblastoma remains largely unknown. Methods The expression of SNHG16, microRNA (miR)-338-3p and polo-like kinase 4 (PLK4) mRNA was measured using quantitative real-time polymerase chain reaction. The protein levels of PLK4, multidrug resistance protein 1 (MRP1), multidrug-resistance gene 1-type p-glycoprotein (P-gp) and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway-related proteins were detected by Western blot. The half maximal inhibitory concentration (IC50) value, cell proliferation, migration and invasion were analyzed using Cell Counting Kit-8 assays or Transwell assay. Apoptotic cells were measured by Flow cytometry. The interaction between miR-338-3p and SNHG16 or PLK4 was confirmed by dual-luciferase reporter and RNA immunoprecipitation assay. In vivo experiments were conducted through the murine xenograft model. Results SNHG16 was up-regulated, while miR-338-3p was down-regulated in cisplatin-resistant neuroblastoma tissues and cells. SNHG16 silencing weakened cisplatin resistance, reflected by the reduction of IC50 value, down-regulation of MRP-1 and P-gp protein expression, suppression of proliferation, migration and invasion, as well as enhancement of apoptosis in SNHG16 deletion cisplatin-resistant neuroblastoma cells. Besides that, SNHG16 could regulate PLK4 expression by sponging miR-338-3p and SNHG16/miR-338-3p/PLK4 axis could affect the activation of PI3K/AKT pathway in cisplatin-resistant neuroblastoma cells. MiR-338-3p inhibition attenuated SNHG16 deletion-mediated impairment on cisplatin resistance and PLK4 overexpression reversed the decrease of cisplatin-resistance induced by miR-338-3p re-expression. Furthermore, SNHG16 knockdown contributed to the anti-tumor effect of cisplatin in neuroblastoma in vivo. Conclusion SNHG16 contributed to the tumorigenesis and cisplatin resistance in neuroblastoma possibly through miR-338-3p/PLK4 pathway, indicating a novel insight for overcoming chemoresistance in neuroblastoma patients.

New Evidence for P-gp-Mediated Export of Amyloid-β Peptides in Molecular, Blood-Brain Barrier and Neuronal Models

“…Expression of P-gp protein in neurons has been a point of contention. For example, several groups have demonstrated P-gp expression in neuronally-derived cell lines [ 35 , 36 , 37 , 38 ] and on peripheral nerve tissue at the blood-nerve-barrier (BNB) [ 39 , 40 , 41 ], whereas others have failed to do so or have demonstrated that it is only expressed in the context of brain injury or pathology [ 42 , 43 , 44 , 45 , 46 , 47 ].…”

Potential Role of miRNAs in the Acquisition of Chemoresistance in Neuroblastoma

“…15.99 Down-regulated in resistant NB [77,78] Down-regulated in esophageal squamous carcinoma cells [79] miR-497 6.92…”

“…In detail, miR-27b and miR-16-1 expression levels were found to be reduced by 33.1 and 23.5 fold, respectively, and miR-218 expression was diminished by 9.09 fold, while miR-15a, miR-126, and miR-19b were down-regulated (slightly, but significantly) by 2.8, 2.7, and 1.73 fold, respectively. [59], gastric [60,61], and ovarian [62,63] cancer, and osteosarcoma [64] miR-126a 9.66 Not evaluated Down-regulated in colorectal [65] and breast cancer [66] and in renal cell carcinoma [67] miR-218 12.30 Up-regulated in MYCN-amplified and in metastatic NB [68][69][70] Down-regulated in glioma cells [71], colorectal [72], gallbladder [73], bladder [74], and lung cancer [75,76] miR-338 15.99 Down-regulated in resistant NB [77,78] Down-regulated in esophageal squamous carcinoma cells [79] miR-497 6.92…”

Silencing of long non‐coding RNADLX6‐AS1 weakens neuroblastoma progression by the miR‐513c‐5p/PLK4 axis

“…Recent work uncovered that PLK4 was a downstream effector of the SNHG16/SNHG1/miR-338-3p axis in regulating NB progression. 32,33 Tian et al demonstrated that PLK4 accelerated NB cell epithelialmesenchymal transition process by activating the PI3K/ Akt signaling, which was implicated in NB carcinogenesis. 34,35 Additionally, direct evidence of the novel mechanism in tumor growth in vivo was absent, which will be conducted in further work.…”

“…Furthermore, we showed that DLX6‐AS1 functioned as a posttranscriptional regulator of PLK4 expression by sponging miR‐513c‐5p. Recent work uncovered that PLK4 was a downstream effector of the SNHG16/SNHG1/miR‐338‐3p axis in regulating NB progression 32,33 . Tian et al demonstrated that PLK4 accelerated NB cell epithelial–mesenchymal transition process by activating the PI3K/Akt signaling, which was implicated in NB carcinogenesis 34,35 .…”