ObjectiveTo examine the role of microRNA (miR)-205 in proliferation, migration and invasion of nasopharyngeal carcinoma (NPC).MethodsThe human NPC cell line CNE2 was transfected with miR-205 mimic, anti-miR-205 inhibitor or scrambled oligonucleotide (control). Cell proliferation was assessed via MTT assay. Cell migration and invasion were evaluated by transwell migration and Matrigel® invasion assay, respectively. Radiation induced apoptosis was quantified via Caspase-Glo3/7 assay. Apoptotic proteins and epithelial–mesenchymal transition (EMT) proteins were semiquantified by Western blot analysis.ResultsOverexpression of miR-205 increased the proliferation, migration and invasion of CNE2 cells, and decreased radiation-induced apoptosis compared with control cells. MiR-205 overexpression downregulated E-cadherin and upregulated Snail expression via downregulation of PTEN and upregulation of AKT.ConclusionMiR-205 plays vital roles in tumourigenesis and tumour progression in NPC, and may be a potential treatment target.

PurposeThe purpose of this study was to explore the frequencies of ALK and ROS1 fusion genes in EGFR-mutant lung adenocarcinoma patients and examine the therapeutic efficacies of EGFR-tyrosine kinase inhibitors (TKIs).Materials and methodsA total of 421 EGFR-mutated patients taking EGFR-TKIs were examined for ALK and ROS1 fusion genes based on reverse transcription-polymerase chain reaction (RT-PCR). Progression-free survival (PFS) and overall survival (OS) were evaluated by the Kaplan–Meier method and compared by the log-rank test.ResultsThe mutations of ALK rearrangement (n=10) and ROS1 rearrangement (n=3) were detected. All the patients received EGFR-TKIs, and eight took subsequent ALK/ROS1 inhibitor. PFS was longer in single EGFR mutants (n=408) than in EGFR/ALK or EGFR/ROS1 counterparts (n=13; 10.7 vs 6.6 months, P=0.004). No difference in OS existed between single EGFR and EGFR/ALK or EGFR/ROS1 mutants (21.0 vs 23.0 months, P=0.196). The median PFS of eight patients treated with ALK/ROS1 inhibitor was 6.0 months.ConclusionConcomitant ALK/ROS1 fusion genes occurred in 3.1% EGFR-mutated lung adenocarcinoma patients. Concomitant ALK/ROS1–EGFR mutations may influence the therapeutic efficacy of EGFR-TKIs.

Nasopharyngeal carcinoma (NPC) is an important type of head and neck malignant cancer with geographical distribution. MicroRNA-449b-5p (miR-449b-5p) is related to the development of various cancers, while its function in NPC remains unknown. The present study aimed to investigate the role and target gene of miR-449b-5p in NPC. Expressions of miR-449b-5p in NPC cell lines and clinical tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was determined by MTT and colony formation assays. Migration and invasion abilities after different treatment were evaluated by wound healing and Transwell assays, respectively. Dual-luciferase reporter assay was performed to explore the relationship between miR-449b-5p and tumour protein D52 (TPD52). TPD52 expression was determined by qRT-PCR and western blot assay. miR-449b-5p was significantly downregulated in NPC cell lines and clinical tissues than the matched control. Overexpression of miR-449b-5p inhibited proliferation, migration and invasion of NPC cells. Dual-luciferase reporter assay indicated that miR-449b-5p directly targeted TPD52. Furthermore, shRNA-mediated downregulation of TPD52 rectified the promotion of cell migration and invasion by miR-449b-5p inhibition. In conclusion, the present study suggests that miR-449b-5p, as a novel tumour-suppressive miRNA against NPC, inhibits proliferation, migration and invasion of NPC cells via inhibiting TPD52 expression.

Despite the recent development of treatment strategies for nasopharyngeal carcinoma, the effective management of this disease remains a challenging clinical problem. A better understanding of the regulatory roles of miR‐194 and mitogen‐activated protein kinase kinase kinase 3 ( MAP 3K3) in the nasopharyngeal‐carcinoma‐related gene network is required to address this issue. Here, we measured relative expression of miR‐194 in human nasopharyngeal carcinoma tissues and normal epithelial tissues by quantitative real time PCR . We transfected cultured CNE ‐1 and C666‐1 cells with miR‐194 mimics, and then examined the effects on cell proliferation, cell migration and invasion. Luciferase reporter assay was used to validate the putative binding between miR‐194 and MAP 3K3. We then examined the effect of knockdown and overexpression of MAP3K3 on cell tumorigenesis. Expression of miR‐194 is significantly down‐regulated in nasopharyngeal carcinoma specimens and tumor cell lines when compared with normal controls. In addition, miR‐194 suppressed tumor cell proliferation and viability, as well as migration and invasion of carcinoma cells. We found that miR‐194 binds the 3′ untranslated region of MAP3K3, and knockdown of miR‐194 inhibited nasopharyngeal carcinoma cell proliferation, migration and invasion. In accordance, overexpression of MAP3K3 reversed the inhibitory effects of miR‐194 in carcinoma cells. This study suggests that expression of miR‐194 is down‐regulated in nasopharyngeal carcinoma, and that miR‐194 can directly target MAP 3K3 to regulate tumor progression. Given the pivotal involvement of MAP 3K3 in nasopharyngeal carcinoma development, targeting miR‐194 may be a novel strategy for the treatment of nasopharyngeal carcinoma.