Picropodophyllin inhibits tumor growth of human nasopharyngeal carcinoma in a mouse model.

Insulin-like growth factor-1 receptor (IGF-1R) is a cell membrane receptor with tyrosine kinase activity and plays important roles in cell transformation, tumor growth, tumor invasion, and metastasis. Picropodophyllin (PPP) is a selective IGF-1R inhibitor and shows promising antitumor effects for several human cancers. However, its antitumor effects in nasopharyngeal carcinoma (NPC) remain unclear. The purpose of this study is to investigate the antitumor activity of PPP in NPC using in vitro cell culture and in vivo animal model. We found that PPP dose-dependently decreased the IGF-induced phosphorylation and activity of IGF-1R and consequently reduced the phosphorylation of Akt, one downstream target of IGF-1R. In addition, PPP inhibited NPC cell proliferation in vitro. The half maximal inhibitory concentration (IC50) of PPP for NPC cell line CNE-2 was ≤1 µM at 24h after treatment and ≤0.5 µM at 48 h after treatment, respectively. Moreover, administration of PPP by intraperitoneal injection significantly suppressed the tumor growth of xenografted NPC in nude mice. Taken together, these results suggest targeting IGF-1R by PPP may represent a new strategy for treatment of NPCs with positive IGF-1R expression.

Long non-coding RNA 319 facilitates nasopharyngeal carcinoma carcinogenesis through regulation of miR-1207-5p/KLF12 axis.

Long non-coding RNAs (lncRNAs) have been wildly verified to modulate multiple tumorigeneses, especially nasopharyngeal carcinoma (NPC). In present study, we aim to investigate the role of LINC00319 in the NPC carcinogenesis. It was indicated that LINC00319 was markedly increased in NPC tissues and cells in comparison to their corresponding controls. Moreover, the aberrant overexpression of LINC00319 indicated the poor prognosis of NPC patients. Silence of LINC00319 was able to suppress NPC cell growth in vitro while overexpression of LINC00319 inversed this process. Moreover, in vivo tumor xenografts were established using CNE-1/SUNE-1 cells to investigate the function of LINC00319 in NSCLC tumorigenesis. Rescue assay was performed to further confirm that LINC00319 contributed to NPC progression by regulating miR-1207-5p/KLF12 signal pathway. Taken together, our study discovered the oncogenic role of LINC00319 in clinical specimens and cellular experiments, showing the potential LINC00319/miR-1207-5p/KLF12 pathway. This results and findings provide a novel insight for NPC tumorigenesis.

Long non-coding RNA EWSAT1 promotes human nasopharyngeal carcinoma cell growth in vitro by targeting miR-326/-330-5p.

Long non-coding RNA (lncRNA) Ewing sarcoma associated transcript 1 (EWSAT1) has been identified as an oncogene, and its dysregulation is closed corrected with tumor progression in Ewing sarcoma. Recently, high-through put analysis reveals that EWSAT1 is also highly expressed in human nasopharyngeal carcinoma (NPC). However, whether the aberrant expression of EWSAT1 in NPC is corrected with malignancy or prognosis has not been expounded. Herein, we identified that EWSAT1 was up-regulated in NPC tissues and cell lines, and higher expression of EWSAT1 resulted in a markedly poorer survival time. EWSAT1 over-expression facilitated, while EWSAT1 silencing impaired cell growth in NPC. In addition, mechanistic analysis demonstrated that EWSAT1 up-regulated the expression of miR-326/330-5p clusters targeted gene cyclin D1 through acting as a competitive 'sponge' of miR-326/330-5p clusters. Collectively, our data revealed that EWSAT1 promotes NPC cell growth in vitro through up-regulating cyclin D1 partially via 'spongeing' miR-326/330-5p clusters.

Effects of TESTIN gene expression on proliferation and migration of the 5-8F nasopharyngeal carcinoma cell line.

PURPOSE: To investigate effects of the TESTIN (TES) gene on proliferation and migration of highly metastatic nasopharyngeal carcinoma cell line 5-8F and the related mechanisms. MATERIALS AND METHODS: The target gene of human nasopharyngeal carcinoma cell line 5-8F was amplified by PCR and cloned into the empty plasmid pEGFP-N1 to construct a eukaryotic expression vector pEGFP-N1-TES. This was then transfected into 5-8F cells. MTT assays, flow cytometry and scratch wound tests were used to detect the proliferation and migration of transfected 5-8F cells. RESULTS: A cell model with stable and high expression of TES gene was successfully established. MTT assays showed that the OD value of 5-8F/TES cells was markedly lower than that of 5-8F/GFP cells and 5-8F cells (p<0.05). Flow cytometry showed that the apoptosis rate of 5-8F/TES cells was prominently increased compared with 5-8F/GFP cells and 5-8F cells (p<0.05). In vitro scratch wound assays showed that, the width of the wound area of 5-8F/TES cells narrowed slightly, while the width of the wound area of 5-8F/ GFP cells and 5-8F cells narrowed sharply, suggesting that the TES overexpression could inhibit the migration ability. CONCLUSIONS: TES gene expression remarkably inhibits the proliferation of human nasopharyngeal carcinoma cell line 5-8F and reduces its migration in vitro. Thus, it may be a potential tumor suppressor gene for nasopharyngeal carcinoma.