MicroRNA-30a suppresses non-small-cell lung cancer by targeting Myb-related protein B.

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.

AKAP95 promotes cell cycle progression via interactions with cyclin E and low molecular weight cyclin E.

AKAP95 in lung cancer tissues showed higher expression than in paracancerous tissues. AKAP95 can bind with cyclin D and cyclin E during G1/S cell cycle transition, but its molecular mechanisms remain unclear. To identify the mechanism of AKAP95 in cell cycle progression, we performed AKAP95 transfection and silencing in A549 cells, examined AKAP95, cyclin E1 and cyclin E2 expression, and the interactions of AKAP95 with cyclins E1 and E2. Results showed that over-expression of AKAP95 promoted cell growth and AKAP95 bound cyclin E1 and E2, low molecular weight cyclin E1 (LWM-E1) and LWM-E2. Additionally AKAP95 bound cyclin E1 and LMW-E2 in the nucleus during G1/S transition, bound LMW-E1 during G1, S and G2/M, and bound cyclin E2 mainly on the nuclear membrane during interphase. Cyclin E2 and LMW-E2 were also detected. AKAP95 over-expression increased cyclin E1 and LMW-E2 expression but decreased cyclin E2 levels. Unlike cyclin E1 and LMW-E2 that were nuclear located during the G1, S and G1/S phases, cyclin E2 and LMW-E1 were expressed in all cell cycle phases, with cyclin E2 present in the cytoplasm and nuclear membrane, with traces in the nucleus. LMW-E1 was present in both the cytoplasm and nucleus. The 20 kDa form of LMW-E1 showed only cytoplasmic expression, while the 40 kDa form was nuclear expressed. The expression of AKAP95, cyclin E1, LMW-E1 and -E2, might be regulated by cAMP. We conclude that AKAP95 might promote cell cycle progression by interacting with cyclin E1 and LMW-E2. LMW-E2, but not cyclin E2, might be involved in G1/S transition. The binding of AKAP95 and LMW-E1 was found throughout cell cycle.

Dihydroartemisinin inhibits glucose uptake and cooperates with glycolysis inhibitor to induce apoptosis in non-small cell lung carcinoma cells.

Despite recent advances in the therapy of non-small cell lung cancer (NSCLC), the chemotherapy efficacy against NSCLC is still unsatisfactory. Previous studies show the herbal antimalarial drug dihydroartemisinin (DHA) displays cytotoxic to multiple human tumors. Here, we showed that DHA decreased cell viability and colony formation, induced apoptosis in A549 and PC-9 cells. Additionally, we first revealed DHA inhibited glucose uptake in NSCLC cells. Moreover, glycolytic metabolism was attenuated by DHA, including inhibition of ATP and lactate production. Consequently, we demonstrated that the phosphorylated forms of both S6 ribosomal protein and mechanistic target of rapamycin (mTOR), and GLUT1 levels were abrogated by DHA treatment in NSCLC cells. Furthermore, the upregulation of mTOR activation by high expressed Rheb increased the level of glycolytic metabolism and cell viability inhibited by DHA. These results suggested that DHA-suppressed glycolytic metabolism might be associated with mTOR activation and GLUT1 expression. Besides, we showed GLUT1 overexpression significantly attenuated DHA-triggered NSCLC cells apoptosis. Notably, DHA synergized with 2-Deoxy-D-glucose (2DG, a glycolysis inhibitor) to reduce cell viability and increase cell apoptosis in A549 and PC-9 cells. However, the combination of the two compounds displayed minimal toxicity to WI-38 cells, a normal lung fibroblast cell line. More importantly, 2DG synergistically potentiated DHA-induced activation of caspase-9, -8 and -3, as well as the levels of both cytochrome c and AIF of cytoplasm. However, 2DG failed to increase the reactive oxygen species (ROS) levels elicited by DHA. Overall, the data shown above indicated DHA plus 2DG induced apoptosis was involved in both extrinsic and intrinsic apoptosis pathways in NSCLC cells.

Prognostic value of SATB2 expression in patients with esophageal squamous cell carcinoma.

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.

[Relationship between AKAP95, cyclin E1, cyclin D1, and clinicopathological parameters in lung cancer tissue].

OBJECTIVE: To investigate the correlation between expression of A-kinase anchoring protein 95 (AKAP95) and protein expression of cyclin E1 and cyclin D1 in lung cancer tissue. METHODS: Fifty-one cases of lung cancer were included in the study. The protein expression of AKAP95, cyclin E1, and cyclin D1 were measured by immunohistochemistry. RESULTS: The protein expression of cyclin E1 in lung cancer tissues was significantly higher than that in para-cancerous tissues (positive rate: 75.56%vs 20%, P < 0.01); its expression showed no relationship with histopathological type, lymph node metastasis, and cellular differentiation (P > 0.05). The protein expression of cyclin D1 in lung cancer tissues was higher than that in para-cancerous tissues (positive rate: 69.39% vs 14.29%); its expression showed a significant relationship with histopathological type (P < 0.05). The expression of AKAP95 was correlated with the protein expression of cyclin E1 and cyclin D1 in lung cancer tissues (P < 0.01). CONCLUSION: Cyclin E1 and cyclin D1 are highly expressed in lung cancer tissue, suggesting that they play an important role in the development and progression of lung cancer. The protein expression of cyclin E1 has no relationship with cellular differentiation, lymph node metastasis, and histopathological type of lung cancer, and the protein expression of cyclin D1 has a significant relationship with histopathological type. The expression of AKAP95 is correlated with the protein expression of cyclin E1 and cyclin D1 in lung cancer tissue.

[Expression of A-kinase anchor protein 95, cyclin E2, and connexin 43 in lung cancer tissue, clinical significance of their expression, and their expression correlation].

OBJECTIVE: To study the expression of A-kinase anchor protein 95 (AKAP95), cyclin E(2), and connexin 43 (Cx43) in lung cancer tissue, the clinical significance of their expression, and the expression correlation among the three proteins. METHODS: Fifty-one samples of lung cancer tissue were examined by immunohistochemistry to measure the expression of AKAP95, cyclin E2, and Cx43. RESULTS: The positive rate of AKAP95 expression in lung cancer tissue was significantly higher than that in paracancerous tissue (82.35% vs 33.33%, P < 0.05); AKAP95 expression was associated with the cell differentiation and histopathological type of lung cancer (P < 0.05). The positive rate of cyclin E(2) expression in lung cancer tissue was significantly higher than that in paracancerous tissue (43.14% vs 13.33%, P < 0.05); cyclin E(2) expression was associated with the lymph node metastasis and histopathological type of lung cancer (P < 0.05). The positive rate of Cx43 expression in lung cancer tissue was lower than that in paracancerous tissue (60.78% vs 80.00%); Cx43 expression was associated with the cell differentiation, lymph node metastasis, and histopathological type of lung cancer (P < 0.05). There was correlation between each two of AKAP95 expression, cyclin E(2) expression, and Cx43 expression in lung cancer tissue. CONCLUSION: High expression of AKAP95 and cyclin E(2) plays an important role in the occurrence and development of lung cancer. AKAP95 expression is associated with the cell differentiation and histopathological type of lung cancer, and cyclin E2 expression is associated with lymph node metastasis and histopathological type. There is correlation between each two of AKAP95 expression, cyclin E(2) expression, and Cx43 expression in lung cancer tissue.

[Development study on model WY multi-functional thoracic cavity closed drainage system].

Based on the improved design of the existing thoracic cavity closed drainage system, a new multi-functional device is developed and is described here in detail. The device is more convenient and more efficient than the existing system. Besides, it has a function of autotransfusion. Animal experimental results show that it has attained the goal of the improved design.