RNA methylation analysis of HNSCC

• Project/Area Number: 17K16903
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Otorhinolaryngology
• Research Institution: Hamamatsu University School of Medicine
• Principal Investigator: Mochizuki Daiki 浜松医科大学, 医学部附属病院, 助教 (40467246)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: RNAメチル化 / DNAメチル化 / METTLE3 / m6A / methylation / 頭頸部癌 / N6-メチルアデノシン

Outline of Final Research Achievements

In this study, we analyzed m6A levels in a well-characterized dataset of 44 matched pairs of HNSCC tissues and normal tissues. m6A levels were examined via relative quantification assay using ELISA. Cancer tissues had significantly lower levels of m6A than matched normal mucosa (P < 0.01). m6A levels were evaluated according to various clinical characteristics and prognostic implications. Notably, we found that m6A levels were significantly correlated with recurrence (P = 0.031). Low levels of m6A were correlated with poor survival (DFS; log-rank test, P = 0.031). In multivariate analysis, low levels of m6A were evaluated as a significant independent prognostic factor of DFS (hazard ratio: 3.606, 95% confidence interval: 1.262&#8211;10.306; P = 0.017). HNSCC cells treated with METTL3 siRNA showed a reduction in growth and a decrease in m6A levels. Taken together, our findings showed that low levels of m6A and subsequent overexpression of METTL3 may affect the development of HNSCC.

Academic Significance and Societal Importance of the Research Achievements

DNAメチル化などの可逆的な塩基修飾が、癌化機構に影響を与えていることが解明されている。RNAにもアデノシン6位窒素原子へのメチル基の付加反応（m6A）という塩基修飾が、DNAよりも動的に存在しており、癌とRNAメチル化について研究を行ってきた。頭頸部癌では、m6Aの増加は予後不良群に認めた。さらにRNAメチル化メチルトランスフェラーゼであるMETTL3遺伝子を頭頸部細胞株でノックダウンを施行し、癌細胞増殖性の抑制とm6Aの減少を認めた。これらの結果は、頭頸部発癌におけるm6Aの重要性を示すものである。今後の展開として、治療後の腫瘍モニタリング、リキッドバイオプシーへの応用などが期待される。

Research Products

• [Journal Article] Genes locating 18q23 are epigenetic markers and prognostic significance in patients with head and neck cancer (2019)
  • Author(s): Misawa K, Kanazawa T, Mochizuki D, Imai A, Mima M, Yamada S, Morita K, Misawa Y, Shinmura K and Mineta H
  • Journal Title: Cancers (Basel) Volume: 11(3) Pages: 401-401
  • Peer Reviewed / Open Access
• [Journal Article] SALL2 Is a Novel Prognostic Methylation Marker in Patients with Oral Squamous Carcinomas: Associations with SALL1 and SALL3 Methylation Status. (2019)
  • Author(s): Imai A, Mochizuki D, Misawa Y, Nakagawa T, Endo S, Mima M, Yamada S, Kawasaki H, Kanazawa T, Misawa K.
  • Journal Title: DNA and Cell Biology Volume: 38 Issue: 7 Pages: 678-687
  • DOI: 10.1089/dna.2018.4597
  • Peer Reviewed / Open Access
• [Journal Article] 5-Hydroxymethylcytosine and ten-eleven translocation dioxygenases in head and neck carcinoma (2019)
  • Author(s): Misawa K, Yamada S, Mima M, Nakagawa T, Kurokawa T, Imai A, Mochizuki D, Morita K, Ishikawa R, Endo S and Misawa Y
  • Journal Title: Journal of Cancer Volume: 10(21) Issue: 21 Pages: 5306-5314
  • DOI: 10.7150/jca.34806
  • Peer Reviewed / Open Access
• [Journal Article] Epigenetic modification of SALL1 as a novel biomarker for the prognosis of early stage head and neck cancer (2018)
  • Author(s): Misawa Kiyoshi、Misawa Yuki、Imai Atsushi、Mochizuki Daiki、Endo Shiori、Mima Masato、Ishikawa Ryuji、Kawasaki Hideya、Yamatodani Takashi、Kanazawa Takeharu
  • Journal Title: Journal of Cancer Volume: 9 Issue: 6 Pages: 941-949
  • DOI: 10.7150/jca.23527
  • Peer Reviewed / Open Access
• [Journal Article] Analysis of Site-Specific Methylation of Tumor-Related Genes in Head and Neck Cancer: Potential Utility as Biomarkers for Prognosis (2018)
  • Author(s): Misawa Kiyoshi、Mochizuki Daiki、Imai Atsushi、Mima Masato、Misawa Yuki、Mineta Hiroyuki
  • Journal Title: Cancers Volume: 10 Issue: 1 Pages: 27-27
  • DOI: 10.3390/cancers10010027
  • Peer Reviewed / Open Access
• [Journal Article] The neuropeptide genes SST, TAC1, HCRT, NPY, and GAL are powerful epigenetic biomarkers in head and neck cancer: A site-specific analysis (2018)
  • Author(s): Misawa K, Mima M, Imai A, Mochizuki D, Misawa Y, Endo S, Ishikawa R, Kanazawa T and Mineta H
  • Journal Title: Clinical Epigenetics Volume: 10 Issue: 1 Pages: 52-52
  • DOI: 10.1186/s13148-018-0485-0
  • Peer Reviewed / Open Access
• [Journal Article] Genes encoding neuropeptide receptors are epigenetic markers in patients with head and neck cancer: a site-specific analysis (2017)
  • Author(s): Misawa K, Imai A, Mochizuki D, Misawa Y, Endo S, Hosokawa S, Ishikawa R, Mima M, Shinmura K, Kanazawa T, Mineta H
  • Journal Title: Oncotarget Volume: 8(44) Issue: 44 Pages: 76318-76328
  • DOI: 10.18632/oncotarget.19356
  • Peer Reviewed / Open Access
• [Journal Article] Evaluation of epigenetic inactivation of vascular endothelial growth factor receptors in head and neck squamous cell carcinoma. (2017)
  • Author(s): Misawa Y, Misawa K, Kawasaki H, Imai A, Mochizuki D, Ishikawa R, Endo S, Mima M, Kanazawa T, Iwashita T, Mineta H.
  • Journal Title: Tumour Biol. Volume: 39 Issue: 7 Pages: 1-15
  • DOI: 10.1177/1010428317711657
  • Peer Reviewed / Open Access
• [Presentation] "Genes encoding neuropeptide receptors are epigenetic markers in patients with head and neck cancer: a site-specific analysis " (2018)
  • Author(s): Daiki Mochizuki, Kiyoshi Misawa, Atsushi Imai, Takeharu Kanazawa, Hiroyuki Mineta
  • Organizer: 109rd AACR Annual Meeting 2018
  • Int'l Joint Research