Midkine-Promoter based Conditionally Replicative Adenovirus expressing siRNA against EGFR for Head and Neck Cancer

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H05481
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Otorhinolaryngology
• Research Institution: Kobe University
• Principal Investigator: Nibu Ken-ichi 神戸大学, 医学研究科, 教授 (20251283)
• Co-Investigator(Kenkyū-buntansha): 大月 直樹 神戸大学, 医学研究科, 准教授 (40343264) ; 上原 奈津美 神戸大学, 医学部附属病院, 助教 (40570502)
• Research Collaborator: SHIRAKAWA toshiro
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 頭頸部癌 / Midkine / EGFR / siRNA / 制限増殖型アデノウイルス

Outline of Final Research Achievements

Background: Epidermal growth factor receptor (EGFR) is overexpressed in head and neck squamous cell carcinomas (HNSCCs). Midkine expression is restricted in adult tissues, but is increased in several malignant tumors, including HNSCCs. Here we evaluated the antitumor effect of Midkine-promoter based conditionally replicative adenovirus expressing siRNA against EGFR for targeting HNSCCs expressing Midkine. Methods: A conditionally replicative adenovirus vector controlled by the Midkine promoter, Ad-MK-siEGFR, was generated by integrating gene-expressing siRNA against EGFR. Antitumor effect of Ad-MK-siEGFR was tested in vitro using established HNSCC cell line, T891 with strong Midkine expression. Results: Expression of EGFR in T891 infected with Ad-MKsiEGFR was significantly lower than that of T891 infected with control. Cytotoxicity assays showed significant growth suppression of Ad-MK-siEGFR in T891 cells.

Free Research Field

耳鼻咽喉科頭頸部外科

Academic Significance and Societal Importance of the Research Achievements

今回我々はMidkineプロモーターをつけて腫瘍特異的に増殖する制限増殖型アデノウイルスAd-MKを作成し、さらにこのアデノウイルスに頭頸部扁平上皮癌に高発現している上皮成長因子受容体EGFRに対するsiRNAの遺伝子を組み込んだAd-MKsiEGFRを作成した。in vitroではAd-MK、Ad-MKsiEGFRともに頭頸部癌細胞の増殖を著明に抑制できた。Ad-MKsiEGFRのsiRNAの効果もmRNAおよび蛋白レベルで確認でき、２重の抗腫瘍効果が確認された。本方法は、再発率が高く予後不良である進行性頭頸部癌の新たなより効果的な治療の開発に向けた基礎的な研究となった。