Transcriptome analysis to identify the downstream genes of androgen receptor in dermal papilla cells.

BACKGROUND: Testosterone signaling mediates various diseases, such as androgenetic alopecia and prostate cancer. Testosterone signaling is mediated by the androgen receptor (AR). In this study, we fortuitously found that primary and immortalized dermal papilla cells suppressed AR expression, although dermal papilla cells express AR in vivo. To analyze the AR signaling pathway, we exogenously introduced the AR gene via a retrovirus into immortalized dermal papilla cells and comprehensively compared their expression profiles with and without AR expression. RESULTS: Whole-transcriptome profiling revealed that the focal adhesion pathway was mainly affected by the activation of AR signaling. In particular, we found that caveolin-1 gene expression was downregulated in AR-expressing cells, suggesting that caveolin-1 is controlled by AR. CONCLUSION: Our whole transcriptome data is critical resources for discovery of new therapeutic targets for testosterone-related diseases.

Human Derived Immortalized Dermal Papilla Cells With a Constant Expression of Testosterone Receptor.

Androgenetic alopecia (AGA) is the most common type of hair loss, and is mainly caused by the biological effects of testosterone on dermal papilla cells (DPCs). In vitro culturing of DPCs might be a useful tool for the screening of target molecule of AGA. However, primary DPCs cannot continuously proliferate owing to cellular senescence and cell culture stress. In this study, we introduced mutant cyclin-dependent kinase 4 (CDK4), Cyclin D1, and telomerase reverse transcriptase (TERT) into DPCs. We confirmed protein expression of CDK4 and Cyclin D1, and enzymatic activity of TERT. Furthermore, we found the established cell line was free from cellular senescence. We also introduced the androgen receptor gene using a recombinant retrovirus, to compensate the transcriptional suppressed endogenous androgen receptor in the process of cell proliferation. Furthermore, we detected the efficient nuclear translocation of androgen receptor into the nucleus after the treatment of dihydrotestosterone, indicating the functionality of our introduced receptor. Our established cell line is a useful tool to identify the downstream signaling pathway, which activated by the testosterone.

Smooth muscle cell outgrowth from coronary atherectomy specimens in vitro is associated with less time to restenosis and expression of a key Transcription factor KLF5/BTEB2.

Atherectomy specimens offer an opportunity to study the biology of coronary artery lesions. We cultured smooth muscle cells (SMCs) from specimens obtained from 24 patients with coronary restenosis after angioplasty to study the relationship between activity of SMCs (in vitro outgrowth) and the time course of restenosis. We also examined expression of a Kruppel-like zinc-finger transcription factor 5 (KLF; also known as BTEB2 and IKLF), which is markedly induced in activated SMCs, in the same specimens. SMC outgrowth was observed in 9 of 24 specimens (37.5%). Restenosis occurred sooner (p < 0.01) in patients whose specimens showed outgrowth compared to those whose specimens showed no outgrowth. Immunostaining for KLF5 was more common in specimens with outgrowth (89 vs. 20%, p < 0.01). These data suggest that the number of activated SMCs in lesions may determine in vitro outgrowth and also affect the time to restenosis.