葡萄糖皮质体受体 (GR) 激活与割抗性前列腺癌中增加的cAMP/PKA信号相关
Lynda Bennett1, Praveen Kumar Jaiswal1, Ryan V Harkless1
1Division of Hematology and Oncology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas.
Molecular cancer therapeutics
|November 29, 2023
概括
在抵抗割的前列腺癌中,葡萄糖皮质体受体 (GR) 活性驱动循环腺单酸盐 (cAMP) 信号传递. 通过选择性调制剂和雄激素受体对抗剂一起抑制GR,可以通过向这种途径来延缓癌症的进展.
科学领域:
- 在瘤学瘤学.
- 分子生物学分子生物学
- 内分泌学 在内分泌学.
背景情况:
- 抗化前列腺癌 (CRPC) 可能会对雄激素受体信号抑制 (ARSi) 产生抗性.
- 增加的葡萄糖皮质体受体 (GR) 表达和活性被认为是CRPC的抵抗机制.
- 在AR抑制的CRPC中,GR活动与下游信号通路之间的联系需要进一步阐明.
研究的目的:
- 在ARSi下调查GR转录活性与循环腺单酸盐 (cAMP) 相关的CRPC基因表达之间的关联.
- 评估选择性GR调节剂 (SGRMs) 与CRPC治疗中的AR抗体结合的治疗潜力.
主要方法:
- 在CRPC模型和患者样本中分析GR介导的基因表达.
- 评估cAMP信号通路的激活,包括蛋白激酶抑制剂β (PKIB) 和蛋白激酶A (PKA) 的活性.
- 在体内研究中,使用CRPC异种移植模型治疗了恩扎胺和SGRMs.
- 在患者衍生的异种移植和转移性CRPC样本中对GR活性和cAMP通路基因表达的相关性分析.
主要成果:
- 在ARSi下GR激活可提高cAMP相关基因表达的调节,包括PKIB,导致PKA活性增加.
- 与恩扎胺和SGRMs的联合治疗延迟了小鼠的CRPC进展,并降低了瘤PKIB mRNA水平.
- 转移的CRPC样本和患者衍生的异种移植显示了cAMP通路信号的丰富和高GR活性.
结论:
- GR转录活性促进了AR-对抗CRPC中的cAMP信号,代表了一种新的致癌机制.
- 将SGRM与AR抗剂结合的向GR可能提供一种治疗策略,通过抑制瘤cAMP/PKA通路来延迟CRPC复发.
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