二氢丹参酮I对多药耐药结肠癌及胃肠肿瘤活化成纤维细胞中代谢重编程的调控作用及机制研究

“Warberg effect” and “Epithelial stromal metabolic coupling” are two typical characteristics of tumor metabolic reprogramming. In our previous work, dihydrotanshinone I (DHTS) was found potent reactive oxygen stress (ROS) dependent anti-colon cancer activity and efficient reverse of multi-drug resistance (MDR) in colon cancer cells. Especially, DHTS significantly decreased mRNA expression of Pyruvate dehydrogenase enzyme complex kinase (PDK) both in HCT116 cells and xenograft tumor in nude mice. In this project, we will investigate the regulation of tumor metabolic reprogramming by DHTS on several multi-drug resistant colon cancer cell and xenograft tumor developed by inoculating MDR colon cancer cells subcutaneously into NOD/SCID mice. The regulation of signaling pathways of ROS/Akt/mTOR/HIF1α and PDK4/CREB/RHEB/mTORC1 by DHTS will be studied for the reverse of metabolic reprogramming in MDR colon cancer. In addition, co-culture model of CAF and MDR colon cancer cells in Transwell will be established to evaluate the reversion of drug resistance by DHTS through CAF in MDR colon cancer cells. This study will offer important theoretical basis for the development of cancer adjuvant based on metabolism regulation and valuable information for the structure optimization of DHTS.

"瓦博格效应"及“上皮基质代谢耦联”均为肿瘤代谢的重要特征，也是促使肿瘤耐药及转移的主要原因。申请者前期发现，二氢丹参酮I（dihydrotanshinone I，DHTS）具有活性氧依赖的抗结肠癌及结肠癌多药耐药活性，并对结肠癌细胞及相应荷瘤裸鼠中丙酮酸脱氢酶酶复合体激酶基因表达具有显著的抑制作用。本项目将以结肠癌多药耐药细胞株、结肠癌活化成纤维细胞（colon cancer activating fibroblasts, CAF）及相应的耐药荷瘤裸鼠模型为对象考察DHTS抗结肠癌耐药是否通过ROS/Akt/mTOR/HIF1α与PDK4/CREB/RHEB/mTORC1信号通路实现对代谢重编程的调控；建立耐药结肠癌细胞与CAF共培养模型，探讨DHTS是否通过CAF而间接调控耐药结肠癌细胞有氧糖酵解。本项目研究成果将为DHTS的结构优化及基于代谢调控的肿瘤治疗佐剂开发提供重要理论基础。

代谢重构是肿瘤的重要特征，也是肿瘤耐药发生的主要原因之一。二氢丹参酮I（dihydrotanshinone I，DHTS）被报道具有活性氧依赖的抗结肠癌及结肠癌多药耐药活性。 本项目通过细胞能量代谢检测、基因表达谱分析、类流式组织蛋白检测及其它多种检测方式证明DHTS可有效逆转结肠癌5-FU敏感及耐药细胞株及相应的荷瘤裸鼠中的糖脂代谢重构。对于5-FU敏感结肠癌，DHTS可通过抑制Sirt3/HIF1α及促进PTEN表达，降低有氧糖酵解及脂肪酸β氧化。对于线粒体氧化磷酸化旺盛的5-FU耐药结肠癌，DHTS可通过抑制Nrf2/Nox1/Sirt3信号通路提高耐药结肠癌组织中ROS含量，激活AMPK/ACC1/ACC2信号通路，抑制脂肪酸合成及脂肪酸释放及β氧化，使游离脂肪酸降低，抑制线粒体氧化磷酸化及ATP含量，同时代偿性促进有氧糖酵解。同时，本研究证实DHTS显著抑制结肠癌活化成纤维细胞（colon cancer activating fibroblasts, CAF）增殖，并逆转CAF对结肠癌细胞迁移和侵袭的促进作用。综合以上结果，本研究为丹参酮以脂肪酸代谢为靶点逆转结肠癌耐药提供了理论基础，并对Nrf2/Nox1/Sirt3及AMPK/ACC1/ACC2信号通路对耐药结肠癌中糖脂代谢重构的调控作用提供了重要的启示性线索，具有较好的应用前景和研究意义。