• Journal of Life Science
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• v.28 no.12
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• pp.1432-1437
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• 2018

Clara cell secretory protein (CCSP) plays an important role in protecting the lungs from inflammation. This research focuses on identifying the cis-element for binding the repressor of CCSP gene expression. A DNase I footprinting experiment revealed three protected regions between -812 and -768 bp (45 bp) of the mCCSP promoter. One motif (D3: GCCTGGGAA) was 100% conserved across rat, hamster, and human. The addition of excess amounts of the D3 motif exhibited high competition within that 45 bp range in an electrophoretic mobility shift assay. However, when mutated D3 ($G{\underline{AA}}TG{\underline{TT}}AA$) was used, the competition was significantly reduced. This demonstrates that the D3 motif within that 45 bp region of the mCCSP promoter is an important site for the protein-DNA interaction. Transient transfection assays with -756 Luc resulted in highly decreased expression of CCSP than those with -812 Luc, suggesting that the 45 bp could function as a binding site for the repressor. Co-transfection of KLF4 exhibited significant repression of the -812 Luc but not the -768 Luc which clearly shows that KLF4 might function as a repressor for the CCSP gene and also suggests that the D3 motif is strongly involved in the binding of KLF4. In addition, when anti-KLF4 antibody was added, super-shifted bands were observed. This result demonstrates that KLF4 could function as a repressor by binding to this 45 bp region of the CCSP promoter and that the D3 motif might be involved in the specific binding of KLF4.

• Journal of Life Science
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• v.25 no.12
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• pp.1439-1444
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• 2015

Steroid receptor coactivators (SRC) are transcriptional coactivators. Among SRCs, SRC-3 is the most studied in relation to different types of tumors. However, the role of SRC-3 in early lung development and lung cancer has not been well studied. The expression profiles of SRC-3 showed that SRC-3 contributed to bronchial and alveolar development in embryonic lung development. SRC-3 was strongly expressed in Clara cells and type II alveolar cells during fetal lung development (E17.5- E18.5), and SRC-3 was expressed in both cell types in the adult lung. TTF-1 was expressed in the lungs of heterozygote SRC-3 mice and Clara cell-specific-CCSP-TAg tumor mice, along with SRC-3 expression. The expression of TTF-1 was localized at transformed Clara cells and multifocal adenocarcinomas in lung cancer mice. However, SRC-3 was not expressed in the multifocal adenocarcinomas, suggesting that SRC-3 might not be involved in the invasiveness of lung cancer. Cotransfection of TTF-1 in Clara cell-specific mtCC cell lines resulted in significant activation of CCSP expression. However, cotransfection of SRC-3 had no significant effects on transient transfection. These in vivo and in vitro results suggest that SRC-3 does not play a significant role in lung tumor progression. In conclusion, SRC-3 is involved in bronchial and alveolar development in fetal and adult lungs, but it does not play an important role in the progression of Clara cell-derived lung cancer.

• Journal of Power Electronics
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• v.19 no.1
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• pp.158-167
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• 2019

This research comparatively studies three kinds of flux regulation methods, namely, stored capacitor discharge pulse (SCDP), constant current source pulse (CCSP), and quantitative flux regulation pulse (QFRP), which are used for hybrid permanent magnet (PM) axial field flux-switching memory machines (HPM-AFFSMMs). Through an analysis of the operation principle and the series hybrid PM flux regulation mechanism of the objective machine, the circuit topologies and flux regulation process of these flux regulation methods are addressed in detail. On the basis of a simulation, the flux regulation characteristics of the researched machine during the magnetization and demagnetization processes are comparatively evaluated. Then, machine performance, including back EMF, direct and quadrature axis inductances, and magnetization and demagnetization characteristics, is quantitatively investigated. Results show that the QFRP enables the HPM-AFFSMM to achieve a less harmonic component of back EMF by approximately 7.28% and 7.97% at the magnetization and demagnetization states, respectively, and a more complete magnetization process than the SCDP and CCSP.

• Tuberculosis and Respiratory Diseases
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• v.57 no.4
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• pp.336-344
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• 2004

Background : Immunotherapy for cancer has not been successful because of several obstacles in tumor and its environment. Inappropriate secretions of cytokines and growth factors by tumors cause substantial changes in the immune responses against tumors, affording the tumors some degree of protection from immune attack. Uteroglobin (UG, Clara cell secretory protein) has been known to have anti-inflammatory, immunomodulatory and anti-cancer activities. However, in lung cancer cells, UG expression is decreased. This study investigated the role of UG in the immunomodulation of lung cancer. Methods : The UG protein was overexpressed by Adenovirus(Ad)-UG transduction in non-small cell lung cancer cell lines. The concentration of Prostaglandin $E_2$ ($PGE_2$) was measured by Enzyme Immunoassay (EIA). Peripheral blood mononuclear cells (PBMC) from whole blood were prepared with Ficoll. PBMC were cultured in RPMI 1640, supernatant of A549, or A549 with UG or NS-398. Concentration of Th 1 type and Th 2 type cytokines from PBMC were measured by ELISA. Results : UG suppressed $PGE_2$, Cyclooxygenase-2 (COX-2) product. Both Th1 type such as Interleukin-2 (IL-2), Interferon-${\gamma}$ (IFN-${\gamma}$) and Tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and Th2 type cytokines such as IL-10 and Tumor growth factor-${\beta}$ (TGF-${\beta}$) were increased when PBMC were cultured with supernatant of non small lung cancer cells. UG and COX-2 inhibitor, NS-398 induced normal immune response of PBMC. Although Th 1 type cytokines were increased, Th 2 type cytokines were reduced by UG. Conclusion : UG suppressed PGE2, COX-2 product. Supernatant of NSCLC induced imbalance of immune response of PBMC. However, UG reversed this imbalance. These results suggest that UG may be used in the development of immunotherapy for lung cancer.