Iwasa Yoichi, Mizokami Atsushi, Miwa Sotaro, Koshida Kiyoshi, Namiki Mikio
Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Sciences, 13-1 Takara-machi, Kanazawa-city 929-8640, Japan.
Int J Urol. 2007 Mar;14(3):233-9. doi: 10.1111/j.1442-2042.2007.01532.x.
To investigate the mechanisms of androgen-independent growth in prostate cancer (PCa), we established two PCa cell lines, LN-REC4 and LNCaP-SF, from the androgen-dependent PCa cell line, LNCaP.
LN-Pre and LN-REC4 cells were generated from LNCaP tumors grown on intact and castrated severe combined immunodeficient (SCID) mouse, respectively. After we cultured LNCaP cells under a steroid-free conditions for 6 months in vitro, LNCaP-SF cells were established. To show the character of LN-REC4 and LNCaP-SF cells, androgen sensitivity was investigated through examination of growth rate, and prostate-specific antigen (PSA), androgen receptor (AR), p21, p27, and cyclin D1 expression were examined by reverse transcription-polymerase chain reaction (RT-PCR). Angiogenesis assay in vitro was carried out using conditioned medium. To examine the expression level of vascular endothelial growth factor (VEGF), RT-PCR and enzyme-linked immunosorbent assay were also done.
LN-REC4 cells proliferated better than LNCaP cells in castrated mice and did well irrespective of castration, although responsiveness for androgen of LN-REC4 cells attenuated less than that of LNCaP cells in vitro. LNCaP-SF cells in castrated mice proliferated more rapidly than in normal mice. The PSA expression in LNCaP-SF cells was still induced by androgen. Expression of AR, p21, p27 and cyclin D1 were not changed in LN-REC4 and LNCaP-SF cells. Angiogenesis assay showed that both cells stimulated angiogenesis. LN-REC4 induced VEGF more than LNCaP and LN-Pre cells. However, expression of VEGF per cell in LNCaP-SF was lower than LNCaP cells, suggesting that other factors might be involved in angiogenesis. These cell lines might be a useful tool for researching androgen-independent growth and treatments of recurred PCa.
为研究前列腺癌（PCa）雄激素非依赖性生长的机制，我们从雄激素依赖性PCa细胞系LNCaP建立了两个PCa细胞系，LN-REC4和LNCaP-SF。
LN-Pre和LN-REC4细胞分别从在完整和去势的严重联合免疫缺陷（SCID）小鼠上生长的LNCaP肿瘤中产生。在体外无类固醇条件下培养LNCaP细胞6个月后，建立了LNCaP-SF细胞。为显示LN-REC4和LNCaP-SF细胞的特性，通过检测生长速率研究雄激素敏感性，并通过逆转录聚合酶链反应（RT-PCR）检测前列腺特异性抗原（PSA）、雄激素受体（AR）、p21、p27和细胞周期蛋白D1的表达。使用条件培养基进行体外血管生成测定。为检测血管内皮生长因子（VEGF）的表达水平，还进行了RT-PCR和酶联免疫吸附测定。
在去势小鼠中，LN-REC4细胞比LNCaP细胞增殖更好，且无论去势与否都生长良好，尽管在体外LN-REC4细胞对雄激素的反应性比LNCaP细胞减弱程度小。去势小鼠中的LNCaP-SF细胞比正常小鼠中增殖更快。LNCaP-SF细胞中的PSA表达仍受雄激素诱导。AR、p21、p27和细胞周期蛋白D1在LN-REC4和LNCaP-SF细胞中的表达未改变。血管生成测定表明两种细胞均刺激血管生成。LN-REC4比LNCaP和LN-Pre细胞诱导更多的VEGF。然而，LNCaP-SF中每个细胞的VEGF表达低于LNCaP细胞，提示血管生成可能涉及其他因素。这些细胞系可能是研究雄激素非依赖性生长和复发性PCa治疗的有用工具。
