A Conditional Variational Framework for Dialog Generation

Deep latent variable models have been shown to facilitate the response generation for open-domain dialog systems. However, these latent variables are highly randomized, leading to uncontrollable generated responses. In this paper, we propose a framework allowing conditional response generation based on specific attributes. These attributes can be either manually assigned or automatically detected. Moreover, the dialog states for both speakers are modeled separately in order to reflect personal features. We validate this framework on two different scenarios, where the attribute refers to genericness and sentiment states respectively. The experiment result testified the potential of our model, where meaningful responses can be generated in accordance with the specified attributes.Comment: Accepted by ACL201

Down-regulation of microRNA-151a-5p inhibits proliferation, migration and invasion and enhances chemosensitivity of lung cancer A549 cells

Objective To investigate the effects of mir-151a-5p down-regulation on the proliferation, migration, invasion and chemosensitivity of A549 cells. Methods RT-qPCR was used to detect the expression of mir-151a-5P in 16 surgical specimens of lung adenocarcinoma and in different lung adenocarcinoma cell lines (H1975, H1299, H2228, A549 and HBE). CCK-8 assay, Transwell test and clonogenic assay were used to assess the changes in the proliferation, migration, invasion and clonogenic ability of A549 cells after transfection with a mir-151a-5p inhibitor. Western blotting was performed to detect the expression of epithelial-mesenchymal transition (EMT)-related proteins in the transfected cells; CCK-8 assay and flow cytometry were used to evaluate the changes in cisplatin sensitivity of A549 cells after the transfection. Results The expression of mir-151a-5p was significantly increased in human lung adenocarcinoma tissues as compared with normal lung tissues (P < 0.01). Among the 4 lung adenocarcinoma cell lines, A549 cells expressed the highest levels of mir-151a-5p (P < 0.01). Transfection with the mir-151a-5p inhibitor, compared with the negative control, significantly attenuated the proliferation, migration, invasion and clonogenic ability of A549 cells (P < 0.05). Western blotting revealed a significant enhancement of E-cadherin expression and obviously lowered expressions of N-candherin, vimentin and Notch1 in A549 cells transfected with the mir-151a-5p inhibitor (P < 0.01). CCK-8 assay showed that the IC50 of cisplatin was significantly lowered in mir-151a-5p inhibitor-transfected cells as compared with the negative control group (P < 0.01); the transfection also resulted in a significantly increased apoptotic rate of the cells in response to cisplatin treatment (P < 0.01). Conclusion Down-regulation of mir-151a-5p expression can significantly inhibit the proliferation, migration and invasion of A549 cells and increase their chemosensitivity to cisplati

Advanced glycation end products enhance invasion and migration of colon cancer HCT116 cells in hypoxic microenvironment

Objective To investigate the effects of advanced glycation end products (AGEs) on the proliferation, invasion, migration and epithelial-mesenchymal transition (EMT) of colon cancer HCT116 cells in hypoxic microenvironment. Methods The optimal AGEs concentration (200 μg/mL) and treatment time (48 h) for promoting the proliferation of HCT116 cells were determined through a screening test with CCK-8 assay and used in subsequent experiment. HCT116 cells were treated with AGEs, hypoxia, or their combination, and the cell cycle changes were detected using flow cytometry; the changes in the invasive and migration abilities of the cells in vitro were assessed using Transwell chamber invasion and migration assays. The expressions of HIF-1α, RAGE, E-cadherin, N-cadherin, vimentin and MMP2 proteins in the treated cells were determined with Western blotting. Results Compared with the blank control cells, HCT116 cells exposed to a hypoxic microenvironment showed an increased proliferative activity, but AGEs alone did not significantly affect the cell proliferation. The cells treated with AGEs, hypoxia, and their combination all exhibited enhanced invasion and migration abilities compared with the blank control cells. The results of Western blotting showed that the expression level of HIF-1α, which was low in HCT116 cells in normoxic condition, was increased significantly in a hypoxic condition, and increased further after exposure of the cells to both AGEs and hypoxia. The expression of RAGE was increased after AGEs exposure of the cells in both normal and hypoxic environments, and the increase was more prominent in a hypoxic condition. Exposure to AGEs, hypoxia, and both all resulted in increased expressions of MMP2, N-cadherin and vimentin but lowered expression of E-cadherin in the cells. Conclusion AGEs can further enhance the invasive and migration abilities but has little effect on the proliferation of HCT116 cells exposed to a hypoxic environment