Epigenetic research and liquid biopsy assays in HNSCC

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K20239
• 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: Endo Shiori 浜松医科大学, 医学部附属病院, 診療助教 (10625205)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: リキッドバイオプシー / 頭頸部癌 / メチル化解析

Outline of Final Research Achievements

A technique under development to facilitate monitoring is the serial measurement of circulating tumor DNA (ctDNA). RNA-sequencing of HPV-related cell lines treated with a demethylating agent and MethylCap-sequencing of palatine tonsil cancer tissue, were performed. By combining MethylCap- and RNA-sequencing data, we identified 21 potentially methylated genes. Multivariate Cox regression analysis of a panel of 21 genes, amplified using methylation specific PCR (MSP)was performed. We identified eight DNA methylation probes that were significantly associated with poor prognosis in HPV-related HNSCC patients. ctDNA samples from five HPV-related cancer patients were analyzed for evidence of DNA methylation. We identified a panel of four methylation probes for prediction of recurrence in HPV-related HNSCC patients. These results demonstrate that ctDNA analysis is a technically feasible method for detection of tumor specific DNA methylation in HPV-related HNSCC patients.

Free Research Field

耳鼻咽喉科

Academic Significance and Societal Importance of the Research Achievements

頭頸部癌には、診断、予後、治療効果判定に適した遺伝子マーカーはいまのところ見つかっていない。今回、血漿循環中DNAのメチル化解析による腫瘍再発の検出に有効な遺伝子の抽出を試みた。次世代シークエンサーによる解析から、21候補遺伝子を抽出し、そのうち8遺伝子がHPV関連頭頸部癌の予後と関連することがわかった。そして4遺伝子が、血漿循環中DNAメチル化解析に有効であることが判明した。HPV関連頭頸部癌におけるリキッドバイオプシーによる血漿循環中DNAメチル化解析は、腫瘍の検出に有効である可能性がある結果を得ることができた。