Expression and effect of microRNA-214 in advanced hypopharyngeal carcinoma / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the expression of microRNA-214(miR-214) in advanced hypopharyngeal carcinoma tissues and its effects on the invasion, migration and colone formation of FaDu cells.</p><p><b>METHODS</b>miR-214 expression in 30 cases of advanced hypopharyngeal carcinoma tissues and normal hypopharyngeal mucosa tissues was detected by real-time quantitative polymerase chain reaction (RT-qPCR). miR-214 was upregulated through transfecting the overexpression vector hsa-mir-214 into FaDu cells. The influences of miR-214 upregulation on the invasion, migration, clone formation and Twist expression were measured by Transwell invasion, Transwell migration, plate clone formation and Western blot assays, respectively.</p><p><b>RESULTS</b>The expression of miR-214 in advanced hypopharyngeal carcinoma tissues (0.311 ± 0.206) was significantly less than normal hypopharyngeal mucosa tissues (1.620 ± 1.394; t = 5.09, P < 0.05) . The expression of miR-214 was notably upregulated after tranfected with hsa-mir-214 compared with the negative control group (t = 6.347, P < 0.05). The migration and invasion ability of FaDu cells transfeced with hsa-mir-214 was decreased by comparison with negative control cells (t = 11.6, P < 0.01; t = 6.499, P < 0.05). There was no significant difference of the average clony number and the cloning efficiency between the experimental and negative control groups (t = 0.592, P > 0.05).</p><p><b>RESULTS</b>of Western blot assay showed that, Twist expression in the miR-214-overexpressed group was apparently decreased compared with that in the control group (t = 6.545, P < 0.05).</p><p><b>CONCLUSIONS</b>miR-214 is expressed at a low level in advanced hypopharyngeal carcinoma tissues, and can obviously inhibit the invasion and migration abilities of FaDu cells, possibly because of its inhibiting effect on Twist expression. Additionally, miR-214 plays no significant role in the proliferation of FaDu cells.</p>

Paclitaxel-resistant HeLa cells have up-regulated levels of reactive oxygen species and increased expression of taxol resistance gene 1

This study is to establish a paclitaxel [PTX]-resistant human cervical carcinoma HeLa cell line [HeLa/PTX] and to investigate its redox characteristics and the expression of taxol resistance gene 1 [Txr1]. HeLa cells were treated with PTX and effects of PTX on cell proliferation were detected through cell counting and the MTT assay. Levels of cellular reactive oxygen species [ROS], reduced glutathione [GSH], and oxidized glutathione [GSSG] as well as the ratio of GSH to GSSG were measured by the 2,7-difluorescein diacetate [DCFH-DA] method and the 5,5?-dithiobis[2- nitrobenzoic acid] [DTNB] method. Activities of superoxide dismutase [SOD], catalase [CAT], and glutathione peroxidase [GPx] were determined by the nitrite formation method, the molybdate colorimetric method, and the DTNB colorimetric method, respectively. The level of Txr1 mRNA was determined by real-time PCR. Compared with the regular HeLa cells, HeLa/PTX cells were larger in size and had more cytoplasmic granules. The population doubling time for HeLa/PTX cells was 1.32 times of that of HeLa cells [P < 0.01]. HeLa/PTX cells showed stronger resistance to PTX than HeLa cells with a resistance index of 122.69. HeLa/PTX cells had higher levels of ROS [P < 0.01] and Txr1 mRNA [P < 0.01], lower level of GSH [P < 0.05], and lower activities of SOD [P < 0.01] and GPx [P < 0.05] than HeLa cells. HeLa/PTX cells, with higher levels of ROS and Txr1 mRNA expression, are more resistant to PTX than HeLa cells