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Non-small-cell lung cancer (NSCLC) is one of the leading causes of cancer mortality worldwide. A growing body of evidence indicates that microRNA (miR) have important and diverse roles in the proliferation, apoptosis and metastasis of human cancer cells. In the present study, the molecular regulation mechanism of miR-30a and its potential target, Myb-related protein B (MYBL2) was investigated in NSCLC. Reverse transcription-quantitative polymerase chain reaction results showed that miR-30a was significantly downregulated in NSCLC tissues compared with adjacent normal tissues (P<0.05). MYBL2 has a putative miR-30a target site in its 3'untranslated region according to previous data, prediction databases and TargetScan software. In the present study, a negative correlation was demonstrated between miR-30a and MYBL2 expression in NSCLC. Direct interaction between miR-30a and MYBL2 was also confirmed via a dual-luciferase reporter assay. miR-30a overexpression inhibited the growth of A549 and H460 cells via MTT and bromodeoxyuridine incorporation assays, whereas miR-30a downregulation promoted cell proliferation. In addition, miR-30a overexpression not only increased cell apoptosis and induced cell cycle arrest in A549 and H460 cell lines, but also attenuated tumor growth, and mRNA and protein expression levels of MYBL2. The present findings suggest that miR-30a may suppress NSCLC by targeting MYBL2. [ABSTRACT FROM AUTHOR]

Insulin is associated with the progression of numerous different types of cancer. However, the association between insulin and non-small cell lung carcinoma (NSCLC) remains unknown. The aim of the present study was to evaluate the role of insulin in the proliferation, migration and drug resistance of NSCLC cells, and to determine whether the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathway was involved. NSCLC cells were treated with insulin in the absence or presence of LY294002, an inhibitor of the PI3K/Akt pathway. Following co-incubation with insulin, cell proliferation and drug resistance were measured by MTT; cell migration was examined by wound healing and Transwell assays; and the expression of cyclin A, proliferating cell nuclear antigen (PCNA), p27, matrix metalloproteinase 3 (MMP3), P-gp and proteins involved in the PI3K/Akt pathway were assessed via western blotting. The results of the current study demonstrated that insulin enhanced the proliferation, migration and drug resistance of NSCLC cells. Correspondingly, insulin upregulated the expression of cyclin A, PCNA, MMP3, P-gp and downregulated p27 expression in NSCLC cells. Following treatment with insulin, it was demonstrated that phospho-Akt expression increased in a dose-dependent manner. However, the effects of insulin on NSCLC cells was inhibited by the PI3K/Akt pathway inhibitor LY294002. Therefore, the results of the current study indicate that insulin is associated with the development of NSCLC by activating the PI3K/Akt pathway. This may improve understanding of the mechanism of action of insulin in NSCLC in the future. [ABSTRACT FROM AUTHOR]

SATB2, a member of the family of special AT-rich binding proteins, has been shown to affect numerous tumorigenesis. However, the role of SATB2 in esophageal squamous cell carcinoma (ESCC) remains unclear. In this study, the SATB2 expression was examined at mRNA and protein levels by quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR), Western blotting, and immunohistochemistry in ESCC tissues and adjacent non-cancerous tissues. Statistical analyses were applied to test the associations between SATB2 expression, clinicopathologic factors, and prognosis. Western blotting and qRT-PCR showed that the expression levels of SATB2 mRNA and protein were both significantly lower in SATB2 tissues than those in non-cancerous tissues. Immunohistochemistry analysis showed that SATB2 expression was significantly correlated with clinical stage and Histological differentiation. The results of Kaplan-Meier analysis indicated that a low expression level of SATB2 resulted in a significantly poor prognosis of ESCC patients. Importantly, multivariate analysis showed that low SATB2 expression was an independent prognostic factor for ESCC patients. In sum, our data suggest that SATB2 plays an important role in ESCC progression, and that decreased expression of SATB2 in tumor tissues could be used as a potential prognostic marker for patients with ESCC.