Aplog-1 is a unique analog of tumor-promoting aplysiatoxin that inhibits tumor-promotion by phorbol diesters and proliferation of tumor cells. While the structural features relevant to the biological activities of Aplog-1 remain to be identified, recent studies by us have suggested that local hydrophobicity around the spiroketal moiety of Aplog-1 is a crucial determinant of its anti-proliferative activity. This hypothesis led us to design 12,12-dimethyl-Aplog-1 (3), in which a hydrophobic geminal dimethyl group is installed proximal to the spiroketal moiety to improve biological potency. As expected, 3 was more effective than Aplog-1 in inhibiting cancer cell growth and binding to protein kinase Cδ, a putative receptor responsible for the biological response of Aplog-1. Moreover, an induction test on Epstein-Barr virus early antigen demonstrated 3 to be a better anti-tumor promoter than Aplog-1. These results indicate that 3 is a superior derivative of Aplog-1, and thus a more promising lead for anti-cancer drugs.
Aplog-1是一种独特的促肿瘤阿普唑啉类似物,它能抑制
磷酸二酯对肿瘤的促进作用和肿瘤细胞的增殖。虽然与 Aplog-1
生物活性相关的结构特征仍有待确定,但我们最近的研究表明,Aplog-1 的螺酮分子周围的局部疏
水性是决定其抗增殖活性的关键因素。根据这一假设,我们设计出了 12,12-二甲基-Aplog-1(3),其中在螺旋酮基的近端安装了一个疏
水性二甲基基团,以提高
生物效力。不出所料,3 在抑制癌细胞生长和与蛋白激酶 Cδ 结合方面比 Aplog-1 更有效,蛋白激酶 Cδ 是 Aplog-1
生物反应的受体。此外,对 Epstein-Barr 病毒早期抗原的诱导测试表明,3 比 Aplog-1 具有更好的抗肿瘤促进作用。这些结果表明,3 是 Aplog-1 的高级衍
生物,因此更有希望成为抗癌药物的先导。