Development of innovative biopharmaceuticals for refractory bladder cancer

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K09681
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56030:Urology-related
• Research Institution: Hyogo Medical University
• Principal Investigator: Gotoh Akinobu 兵庫医科大学, 医学部, 教授 (70283885)
• Co-Investigator(Kenkyū-buntansha): 松永 渉 兵庫医科大学, 医学部, 助教 (20415300)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: CRISPRA-Cas9 / Midkine / Adenovirus Vector / Lentiviral Vector

Outline of Final Research Achievements

The CRISPR-Cas9 is thought to have promising clinical potential. However, the off-target effects of Cas9 are a major concern for its application. Therefore, we hypothesized that the adverse effects of off-target gene editing might be minimized if the human codon-optimized Cas9 (hCas9) could be specifically expressed in cancer cells.
We constructed a chimeric adenoviral vector, Ad5F35-MKp-hCas9, and infected human bladder cancer cell lines with this vecto.The hCas9 gene expression was observed in Ad5F35-MKp-hCas9 infected bladder cancer cells but not in non-malignant cells. On the other hand, the cytotoxicity of the adenovirus vector hindered the experiment, we also developed a lentiviral vector for hCas9. Our study showed that the Ad5F35-MKp-hCas9 vector is capable of expressing the hCas9 gene with high specificity in bladder cancer cells. These findings may help in minimizing the risk of off-target effects of gene editing.

Free Research Field

泌尿器系がん治療

Academic Significance and Societal Importance of the Research Achievements

膀胱がんの症例の7割は筋層非浸潤性膀胱がんであり、難治性で再発を繰り返して悪性度を高める性質があるが、現行の治療法は副作用のため患者のQOL低下が著しいため、効果的で副作用の低い膀胱がん治療法開発は大きな意義がある。
本研究で開発したミドカインプロモーターとCas9遺伝子の組み合わせは、Cas9遺伝子の発現を悪性細胞に限定することを可能とするため、CRISPA-Cas9のオフターゲット効果による懸念を払しょくするとともに、血管内皮増殖因子を標的とするガイドRNAとの組み合わせによって、腫瘍に対する特異性を欠く現行の血管新生阻害療法の欠点を克服できるものと考える。