Long Non-Coding RNA TP53TG1 Upregulates SHCBP1 to Promote Retinoblastoma Progression by Sponging miR-33b

Long non-coding RNA (lncRNA) TP53 target 1 (TP53TG1) is known to be strongly associated with tumor and cancer progression. However, its expression profile, unique role, and regulatory pathways in retinoblastoma (RB) are not known. Here, we revealed a large expression of TP53TG1 in RB tissues and cell lines. Conversely, we showed marked suppression of cell proliferation, migration, and invasion in TP53TG1 knocked down RB cells. Mechanistically, we established that TP53TG1 directly interacted with microRNA (miR)-33b in RB cells. Furthermore, TP53TG1 transcripts were found to be inversely correlated with miR-33b in RB tissues. We also showed that miR-33b suppression partly reversed the TP53TG1 knockdown mediated effects on tumor biology. Finally, TP53TG1 was shown to modulate the levels of SHC Binding and Spindle Associated 1 (SHCBP1), a direct target of miR-33b in RB cells. Based on the above data, we propose that TP53TG1 regulates RB progression via its modulation of the miR-33b/SHCBP1 pathway.