De novo biosynthesis of pyrimidine in tumor microenvironment.

• Project/Area Number: 19K16719
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 50010:Tumor biology-related
• Research Institution: Nagasaki University
• Principal Investigator: SAKURA Takaya 長崎大学, 熱帯医学研究所, 助教 (60816726)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2020: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000); Fiscal Year 2019: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: ピリミジン生合成 / ジヒドロオロト酸脱水素酵素 / フマル酸呼吸 / がん微小環境 / ピリミジン生合成経路

Outline of Research at the Start

DNAやRNAを構成するピリミジンの生合成はジヒドロオロト酸脱水素酵素(DHODH)が担っており、ピリミジンを多量に必要とするがん細胞の標的酵素となっている。しかし血流からの前駆体および酸素供給が不十分ながん微小環境におけるピリミジン生合成のメカニズムは不明な点が多い。本研究では阻害剤を用いた逆ケミカルバイオロジーと分子生物学的手法を組み合わせ、がん細胞特異的な新規ピリミジン生合成経路のメカニズムを明らかにする。

Outline of Final Research Achievements

Pyrimidine de novo biosynthesis is an important metabolic pathway for cancer cell proliferation under tumor microenvironment. Dihydroorotate dehydrogenase (DHODH), the rate-limiting enzyme, is one of the targets for the cancer drug development. Cancer cells utilize fumarate respiration for the energy metabolism instead of conventional oxygen respiration due to limited metabolic precursors and oxygen under tumor microenvironment. Metabolome analysis using inhibitors against enzymes of electron transport chain showed that human DHODH likely contributes to fumarate respiration under tumor microenvironment. We also analyze activities of ferulenol and its derivatives against human DHODH and cancer cells, structure-activity relationship (SAR), and several co-crystal structures. This fundamental information might contribute to anti-cancer drug development targeting human DHODH.

Academic Significance and Societal Importance of the Research Achievements

低酸素条件下におけるエネルギー代謝に重要なフマル酸呼吸とヒトDHODHが共役する可能性を示す今回の結果は、がん微小環境で増殖するがん細胞の増殖機構の解明に重要な科学的知見であると言える。さらに複数のFL誘導体のヒトDHODH およびがん細胞に対する阻害活性、構造活性相関、複合体結晶構造解析の結果はヒトDHODHを標的とした抗がん剤の効率的な設計に有益な基盤情報となる。

Research Products

• [Journal Article] Structural and Biochemical Features of Eimeria tenella Dihydroorotate Dehydrogenase, a Potential Drug Target (2020)
  • Author(s): Sato D, Hartuti ED, Inaoka DK, Sakura T, Amalia E, Nagahama M, Yoshioka Y, Tsuji N, Nozaki T, Kita K, Harada S, Matsubayashi M, Shiba T.
  • Journal Title: Genes (Basel) Volume: 11(12) Issue: 12 Pages: 1468-1468
  • DOI: 10.3390/genes11121468
  • Peer Reviewed / Open Access
• [Presentation] Identification of new antimalarial drug candidate that inhibit Plasmodium falciparum mitochondrial dihydroorotate dehydrogenase (2020)
  • Author(s): Hartuti Endah D, Sakura Takaya, Wang Xinying, Mochizuki Kota, Acharjee Rajib, Matsuo Yuichi, Mori Mihoko, Shiomi Kazuro, Nozaki Tomoyoshi, Hamano Shinjiro, Kita Kiyoshi, Inaoka Daniel Ken
  • Organizer: 日本寄生虫学会
• [Presentation] Ascofuranone suppresses cancer cells growth under microenvironment conditions through blockage of the de novo pyrimidine biosynthesis pathway (2020)
  • Author(s): Mohammed S. O. Tagod, Takaya Sakura, Yukiko Miyazaki, Daniel Ken Inaoka, Kiyoshi Kita
  • Organizer: 日本生体エネルギー研究会