Activation of cGMP/PKG/p65 signaling associated with PDE5-Is downregulates CCL5 secretion by CD8+ T cells in benign prostatic hyperplasia
Activation of cGMP/PKG/p65 signaling associated with PDE5-Is downregulates CCL5 secretion by CD8+ T cells in benign prostatic hyperplasia
复制标题
与 PDE5 相关的 cGMP/PKG/p65 信号传导的激活下调良性前列腺增生中 CD8 T 细胞的 CCL5 分泌
DOI：
10.1002/pros.23801
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发表时间：
2019-06-01
期刊：
影响因子：
2.8
通讯作者：
Peng, Jing
中科院分区：
文献类型：
--
作者：
Jin, Song;Xian, Peng;Peng, Jing
背景良性前列腺增生症(BPH)是老年男性最常见的泌尿系疾病，但其潜在的病理生理机制复杂且尚未完全了解。用于治疗BPH的磷酸二酯酶5抑制剂(PDE5-IS)可以上调环鸟苷(CGMP)依赖的蛋白激酶G(PKG)信号，从而抑制前列腺癌的炎症。我们以前的发现表明，CD8(+)T细胞通过分泌CCL5促进低雄激素条件下BPH上皮细胞(BECs)的增殖；然而，cGMP/PKG通路在这一过程中的作用尚不清楚。方法采用免疫组织化学方法检测非那雄胺治疗前6个月以上的前列腺癌组织中CD8(+)T细胞、CCL5、细胞周期蛋白D1和PDE5蛋白的表达。将BPH-1细胞与CD8(+)T细胞或PDE5-IS在低雄激素条件下共培养4d。收集条件培养液、BPH-1细胞和CD8(+)T细胞，用于后续实验。定量聚合酶链式反应检测CCL5信使RNA表达水平。采用酶联免疫吸附试验检测条件培养液中CCL5的含量。用细胞计数试剂盒8检测PDE5-IS对BPH-1/CD8(+)T细胞增殖的影响。采用高脂饮食(HFD)诱导的大鼠前列腺增生症模型，观察cGMP/PKG在体内对CD8(+)T细胞的影响。结果CD8(+)T细胞在BPH组织中的表达与CCL5、Cyclin D1和PDE5的表达呈正相关，而在HFD诱导的大鼠前列腺增生症模型中，PDE5-I激活cGMP/PKG信号通路可抑制CD8(+)T细胞的浸润和CCL5、Cyclin D1的表达。此外，cGMP/PKG通路的激活通过下调核因子-kappaBp65的磷酸化来抑制CD8(+)T细胞分泌CCL5，进而通过CCL5/STAT5/CCND1信号通路抑制BPH-1的生长。结论cGMP/PKG/p65信号通路上调可减少CD8(+)T细胞分泌CCL5，从而抑制低雄激素状态下BECs的增殖，提示5α还原酶抑制剂与PDE5-IS联合应用可能是治疗BPH患者的一种新的、更有效的治疗方法。
Background Benign prostatic hyperplasia (BPH) is the most common urological disease in elderly men, but the underlying pathophysiological mechanisms are complex and not fully understood. Phosphodiesterase type 5 inhibitors (PDE5-Is) used to treat BPH could upregulate the cyclic guanosine monophosphate (cGMP)-dependent protein kinase G (PKG) signaling, which was shown to blunt inflammation in the prostate. Our previous findings indicate that CD8(+) T cells promote the proliferation of BPH epithelial cells (BECs) in low androgen conditions through secretion of CCL5; however, the role of the cGMP/PKG pathway in the process is unclear. Methods Paraffin-embedded tissues were used for expression quantity of CD8(+) T cells, CCL5, cyclin D1, and PDE5 protein by immunohistology in prostate specimens which were/were not treated with finasteride 5 mg daily for at least 6 months before surgery. BPH-1 cells were cocultured with or without CD8(+) T cells or PDE5-Is in low androgen conditions for 4 days. The conditioned media, BPH-1 cells, and CD8(+) T cells were harvested for the subsequent experiments. The quantitative polymerase chain reaction was used for assaying the level of messenger RNA expression of CCL5. CCL5 in the conditioned media was detected by the enzyme-linked immunosorbent assay. The effect of PDE5-Is on cocultured BPH-1/CD8(+) T-cell proliferation was detected by the cell counting kit-8. A high-fat diet (HFD)-induced prostatic hyperplasia rat model was used to investigate the effect of cGMP/PKG activation in CD8(+) T cells in vivo. Results CD8(+) T-cell infiltration into human BPH tissues was positively correlated with the expression of CCL5, cyclin D1, and PDE5, whereas in an HFD-induced prostatic hyperplasia rat model, the activation of the cGMP/PKG signaling by a PDE5-I could suppress the CD8(+) T-cell infiltration and the CCL5 and cyclin D1 expression. Furthermore, the activation of the cGMP/PKG pathway inhibited CCL5 secretion by CD8(+) T cells by downregulating nuclear factor-kappa B p65 phosphorylation, which reduced the growth of BPH-1 through CCL5/STAT5/CCND1 signaling. Conclusions Our results indicate that the upregulation of the cGMP/PKG/p65 signaling reduces CCL5 secretion in CD8(+) T cells, which in turn decreases the proliferation of BECs in low androgen conditions, suggesting that the combination of 5 alpha reductase inhibitors lowering androgen levels and PDE5-Is may be a novel, more effective treatment for BPH patients.