Introduction

The development of a new type of Thymidylate synthase (TS) inhibitor that could inhibit cancer cells' proliferation and anti-angiogenesis is of great significance for cancer's clinical treatment.

Objectives

Our research hopes to develop a TS inhibitor that is more effective than the current first-line clinical treatment of pemetrexed (PTX) and provide a new reference for the clinical treatment of non-small cell lung cancer (NSCLC).

Methods

We obtained a series of novel TS inhibitors by chemical synthesis. Moreover, TS assay and molecular docking to verify the target compound's inhibitory mode. Use MTT assay, colony-forming assay, flow cytometry, and western blot to verify the compound's inhibitory effect on cancer cell proliferation and its mechanism; and explore the compound’s effect on angiogenesis in vitro and in vivo. Further, explore the hit compound's anti-cancer ability through the xenograft tumor model and the orthotopic cancer murine model.

Results

A series of N-(3-(5-phenyl-1,3,4-oxadiazole-2-yl) phenyl)-2,4-dihydroxypyrimidine-5-sulfamide derivatives were synthesized as TS inhibitors for the first time. All target compounds significantly inhibited hTS enzyme activity and demonstrated significant antitumor activity against five cancer cell lines. Notably, 7f had a high selectivity index (SI) and unique inhibitory effects on eight NSCLC cells. In-depth research indicated that 7f could induce apoptosis by the mitochondrial pathway in A549 and PC-9 cells through the upregulation of wild-type P53 protein expression. Additionally, 7f was shown to inhibit angiogenesis in vitro and in vivo. In vivo studies, compared to PTX, 7f significantly inhibited tumor growth in A549 cell xenografts and had a higher therapeutic index (TGI). Moreover, 7f could prolong the survival of the orthotopic lung cancer murine model more effectively than PTX.

Conclusion

The anti-angiogenic effect of 7f provides a new reference for the development of TS inhibitors and the clinical treatment of NSCLC.

中文翻译：

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开发一种能够上调 P53 表达和抑制 NSCLC 血管生成的新型胸苷酸合酶 (TS) 抑制剂

介绍

开发一种新型的抑制癌细胞增殖和抗血管生成的胸苷酸合成酶（TS）抑制剂，对癌症的临床治疗具有重要意义。

目标

我们的研究希望开发出比目前临床一线治疗培美曲塞（PTX）更有效的TS抑制剂，为临床治疗非小细胞肺癌（NSCLC）提供新的参考。

方法

我们通过化学合成获得了一系列新型TS抑制剂。此外，TS检测和分子对接验证目标化合物的抑制模式。采用MTT法、集落形成法、流式细胞仪、western blot验证该化合物对癌细胞增殖的抑制作用及其作用机制；并探索该化合物在体外和体内对血管生成的影响。进一步通过异种移植肿瘤模型和原位癌鼠模型探索hit化合物的抗癌能力。

结果

首次合成了一系列N-(3-(5-苯基-1,3,4-恶二唑-2-基)苯基)-2,4-二羟基嘧啶-5-磺酰胺衍生物作为TS抑制剂。所有目标化合物均显着抑制 hTS 酶活性，并对五种癌细胞系表现出显着的抗肿瘤活性。值得注意的是，7 f对 8 个 NSCLC 细胞具有高选择性指数 (SI) 和独特的抑制作用。深入研究表明，7f可通过上调野生型P53蛋白表达，通过线粒体途径诱导A549和PC-9细胞凋亡。此外，7 f显示在体外和体内抑制血管生成。体内研究，与 PTX 相比，7f显着抑制 A549 细胞异种移植物中的肿瘤生长，并具有更高的治疗指数 (TGI)。此外，7 f可以比 PTX 更有效地延长原位肺癌小鼠模型的存活时间。

结论

7f的抗血管生成作用为TS抑制剂的开发和NSCLC的临床治疗提供了新的参考。