Identification of genes whose expression is upregulated in lung adenocarcinoma cells in comparison with type II alveolar cells and bronchiolar epithelial cells in vivo
ONCOGENE
Authors: Kobayashi, K; Nishioka, M; Kohno, T; Nakamoto, M; Maeshima, A; Aoyagi, K; Sasaki, H; Takenoshita, S; Sugimura, H; Yokota, J
Abstract
To identify genes whose expression is upregulated in lung adenocarcinoma (AdC) cells in comparison with noncancerous peripheral lung epithelial cells, type II alveolar cells and bronchiolar epithelial cells, as well as AdC cells, were isolated by laser capture microdissection, and subjected to cDNA microarray analysis of 637 human cancer-related genes. Each of the component cells was obtained from several different individuals and analysed independently. As a comparison, two lung AdC cell lines and two primarily cultured normal lung epithelial cell lines were also subjected to cDNA microarray analysis. Four genes, TOP2A, MMP15, MX2 and KOC1, were commonly upregulated in microdissected AdC cells in comparison with microdissected epithelial cells. Hierarchical clustering analysis revealed that differences in gene-expression profiles were more evident between cultured and uncultured cells than between cancerous and noncancerous cells. To further identify the common molecular targets of AdC cells in vivo, quantitative real-time RT-PCR was performed against the four genes upregulated by cDNA microarray analysis. The TOP2A, MMP15, MX2 and KOC1 genes were overexpressed in 10/10 (100%), 8/10 (80%), 5/10 (50%) and 3/10 (30%) microdissected AdC cell samples, respectively, in comparison with any of nine independently microdissected noncancerous epithelial cell samples. The TOP2A gene was commonly overexpressed in lung AdC cells, as previously reported. In addition, the MMP15 and MX2 genes were identified, for the first time, as being commonly overexpressed in lung AdC cells. These results strongly indicate that the MMP15 and MX2 genes could be novel markers for molecular diagnosis and therapy of lung AdC.
Nuclear Progestin Receptor Phosphorylation by Cdk9 Is Required for the Expression of Mmp15, a Protease Indispensable for Ovulation in Medaka
CELLS
Authors: Ogiwara, Katsueki; Takahashi, Takayuki
Abstract
Ovulation denotes the discharge of fertilizable oocytes from ovarian follicles. Follicle rupture during ovulation requires extracellular matrix (ECM) degradation at the apex of the follicle. In the teleost medaka, an excellent model for vertebrate ovulation studies, LH-inducible matrix metalloproteinase 15 (Mmp15) plays a critical role during rupture. In this study, we found that follicle ovulation was inhibited not only by roscovitine, the cyclin-dependent protein kinase (CDK) inhibitor, but also by CDK9-inhibitor II, a specific CDK9 inhibitor. Inhibition of follicle ovulation by the inhibitors was accompanied by the suppression of Mmp15 expression in the follicle. In follicles treated with the inhibitors, the formation of the phosphorylated nuclear progestin receptor (Pgr) was inhibited. Roscovitine treatment caused a reduction in the binding of Pgr to the promoter region of mmp15. The expression of Cdk9 and cyclin I (Ccni), and their association in the follicle was demonstrated, suggesting that Cdk9 and Ccni may be involved in the phosphorylation of Pgr in vivo. LH-induced follicular expression of ccni/Ccni was also shown. This study is the first to report the involvement of CDK in ECM degradation during ovulation in a vertebrate species.