Singh Ravibhushan, Browning Jeff L, Abi-Habib Ralph, Wong Kevin, Williams Simon A, Merchant Rosemina, Denmeade Samuel R, Buckley Thomas J, Frankel Arthur E
Cancer Research Institute, Scott & White Memorial Hospital, 5701 South Airport Road, Temple, TX 76502, USA.
Anticancer Drugs. 2007 Aug;18(7):809-16. doi: 10.1097/CAD.0b013e3280bad82d.
Native proaerolysin is a channel-forming bacterial protoxin that binds to cell-surface receptors and then is activated by furin or furin-like proteases. We genetically engineered proaerolysin by replacing the furin-cleavage sequence with a prostate-specific antigen-selective sequence. The recombinant modified proaerolysin was expressed and purified from Aeromonas salmonicida in good yields and purity. Recombinant modified proaerolysin had no furin sensitivity and markedly increased prostate-specific antigen sensitivity relative to wild-type proaerolysin. Human prostate cancer cells were significantly more sensitive to recombinant modified proaerolysin in the presence of active prostate-specific antigen when compared with the absence of prostate-specific antigen or the presence of potent prostate-specific antigen inhibitors. Most normal human cells with the exception of prostate and renal epithelial cells showed very low sensitivity to recombinant modified proaerolysin. Our results suggest that recombinant modified proaerolysin is a potent prostate-specific antigen-sensitive protoxin that deserves further development for regional therapy of benign and malignant prostate growths.
天然前气单胞菌溶素是一种形成通道的细菌原毒素，它与细胞表面受体结合，然后被弗林蛋白酶或类弗林蛋白酶激活。我们通过用前列腺特异性抗原选择性序列替换弗林蛋白酶切割序列，对前气单胞菌溶素进行了基因工程改造。重组修饰的前气单胞菌溶素以高产量和高纯度从杀鲑气单胞菌中表达并纯化出来。重组修饰的前气单胞菌溶素对弗林蛋白酶不敏感，相对于野生型前气单胞菌溶素，其对前列腺特异性抗原的敏感性显著增加。与不存在前列腺特异性抗原或存在强效前列腺特异性抗原抑制剂相比，在存在活性前列腺特异性抗原的情况下，人前列腺癌细胞对重组修饰的前气单胞菌溶素明显更敏感。除前列腺和肾上皮细胞外，大多数正常人类细胞对重组修饰的前气单胞菌溶素表现出极低的敏感性。我们的结果表明，重组修饰的前气单胞菌溶素是一种强效的前列腺特异性抗原敏感原毒素，值得进一步开发用于良性和恶性前列腺增生的区域治疗。
