PURPOSE: Polo-like kinase 1 (plk1) is a serine/threonine protein kinase essential for multiple mitotic processes. Previous observations have validated plk1 as a promising therapeutic target. Despite being conceptually attractive, the potency and specificity of current plk1-based therapies remain limited. We sought to develop a novel plk1-targeting strategy by constructing an oncolytic adenovirus to selectively silence plk1 in tumor cells. EXPERIMENTAL DESIGN: Two artificial features were engineered into one wild-type adenovirus type 5 (wt-Adv5) genome to generate a new oncolytic adenovirus (M1). First, M1 contains a 27-bp deletion in E1A region, which confers potent, oncolytic efficacy. Second, M1 is armed with a fragment of antisense plk1 cDNA that substitutes the E3 region encoding 6.7K and gp19K. In this design, tumor-selective replication of M1 would activate the native adenovirus E3 promoters to express the antisense plk1 cDNA preferentially in tumor cells and silence tumor-associated plk1 protein. RESULTS: By virtue of combining oncolysis with plk1 targeting, M1 exhibited potent antitumoral efficacy in vitro and in vivo. Systemic administration of M1 plus cisplatin induced complete tumor regression in 80% of orthotopic hepatic carcinoma model mice that were otherwise resistant to cisplatin and disseminated metastases. CONCLUSIONS: Coupling plk1 targeting with oncolysis had shown superior antitumor efficacy. Present findings would benefit the development of novel oncolytic adenoviruses generally applicable to a wide range of molecule-based therapeutics.
PURPOSE: Polo-like kinase 1 (plk1) is a serine/threonine protein kinase essential for multiple mitotic processes. Previous observations have validated plk1 as a promising therapeutic target. Despite being conceptually attractive, the potency and specificity of current plk1-based therapies remain limited. We sought to develop a novel plk1-targeting strategy by constructing an oncolytic adenovirus to selectively silence plk1 in tumor cells. EXPERIMENTAL DESIGN: Two artificial features were engineered into one wild-type adenovirus type 5 (wt-Adv5) genome to generate a new oncolytic adenovirus (M1). First, M1 contains a 27-bp deletion in E1A region, which confers potent, oncolytic efficacy. Second, M1 is armed with a fragment of antisense plk1 cDNA that substitutes the E3 region encoding 6.7K and gp19K. In this design, tumor-selective replication of M1 would activate the native adenovirus E3 promoters to express the antisense plk1 cDNA preferentially in tumor cells and silence tumor-associated plk1 protein. RESULTS: By virtue of combining oncolysis with plk1 targeting, M1 exhibited potent antitumoral efficacy in vitro and in vivo. Systemic administration of M1 plus cisplatin induced complete tumor regression in 80% of orthotopic hepatic carcinoma model mice that were otherwise resistant to cisplatin and disseminated metastases. CONCLUSIONS: Coupling plk1 targeting with oncolysis had shown superior antitumor efficacy. Present findings would benefit the development of novel oncolytic adenoviruses generally applicable to a wide range of molecule-based therapeutics.
Authors: Kathryn Ottolino-Perry; Jean-Simon Diallo; Brian D Lichty; John C Bell; J Andrea McCart Journal: Mol Ther Date: 2009-12-22 Impact factor: 11.454
Authors: Markus Moehler; Maike Sieben; Susanne Roth; Franziska Springsguth; Barbara Leuchs; Maja Zeidler; Christiane Dinsart; Jean Rommelaere; Peter R Galle Journal: BMC Cancer Date: 2011-10-26 Impact factor: 4.430