4. Laryngoscope, 127:921-926, 2017.

PurposeAlthough follicular thyroid cancer (FTC) has a relatively fair prognosis, distant metastasis sometimes results in poor prognosis and survival. There is little understanding of the mechanisms contributing to the aggressiveness potential of thyroid cancer. We showed that hypoxia inducible factor-1α (HIF-1α) induced aggressiveness in FTC cells and identified the underlying mechanism of the HIF-1α-induced invasive characteristics.Materials and MethodsCells were cultured under controlled hypoxic environments (1% O2) or normoxic conditions. The effect of hypoxia on HIF-1α, and epithelial-to-mesenchymal transition (EMT) related markers were evaluated by quantitative real-time PCR, Western blot analysis and immunocytochemistry. Invasion and wound healing assay were conducted to identify functional character of EMT. The involvement of HIF-1α and Twist in EMT were studied using gene overexpression or silencing. After orthotopic nude mouse model was established using the cells transfected with lentiviral shHIF-1α, tissue analysis was done.ResultsHypoxia induces HIF-1α expression and EMT, including typical morphologic changes, cadherin shift, and increased vimentin expression. We showed that overexpression of HIF-1α via transfection resulted in the aforementioned changes without hypoxia, and repression of HIF-1α with RNA interference suppressed hypoxia-induced HIF-1α and EMT. Furthermore, we also observed that Twist expression was regulated by HIF-1α. These were confirmed in the orthotopic FTC model.ConclusionHypoxia induced HIF-1α, which in turn induced EMT, resulting in the increased capacity for invasion and migration of cells via regulation of the Twist signal pathway in FTC cells. These findings provide insight into a possible therapeutic strategy to prevent invasive and metastatic FTC.

The endolymphatic sac (ES) is a cystic organ that is a part of the inner ear and is connected to the cochlea and vestibule. The ES is thought to be involved in inner ear ion homeostasis and fluid volume regulation for the maintenance of hearing and balance function. Many ion channels, transporters, and exchangers have been identified in the ES luminal epithelium, mainly in animal studies, but there has been no functional study investigating ion transport using human ES tissue. We designed the first functional experiments on electrogenic transport in human ES and investigated the contribution of K+ channels in the electrogenic transport, which has been rarely identified, even in animal studies, using electrophysiological/pharmacological and molecular biological methods. As a result, we identified functional and molecular evidence for the essential participation of K+ channels in the electrogenic transport of human ES epithelium. The identified K+ channels involved in the electrogenic transport were KCNN2, KCNJ14, KCNK2, and KCNK6, and the K+ transports via those channels are thought to play an important role in the maintenance of the unique ionic milieu of the inner ear fluid.

Robot-assisted SMG resection was feasible without any significant complications and satisfactory cosmetic results. The safety and oncologic outcome of the procedure should be verified with larger number of patients and longer follow up period.

Abstract-Many have recognized the need to restructure the current internetwork into a much more dynamic networking environment. It is difficult for today's inflexible infrastructure to cope with the fast changing demands of the users. As a result, Software-Defined Network (SDN) was introduced around 2005 to transform today's network to have centralized management, rapid innovation, and programmability by decoupling the control and data planes. This study focuses on developing a firewall application that runs over an OpenFlow-based SDN controller to show that most of the firewall functionalities are able to be built on software, without the aid of a dedicated hardware. Among many OpenFlow controllers that already exist for the public, we have chosen POX written in Python for the experiment; and to create the SDN network topology, we have used VirtualBox and Mininet. In this study, we cover the implementation detail of our firewall application, as well as the experimentation result.