提升非小細胞肺癌檢體EGFR (epidermal growth factor receptor) 基因之突變診斷率

Enhance the Detection Rate of EGFR Mutations in Lung Cancer

蔡明心(Meen-shin Tsai)

指導教授 ： 李憲明 ； 張基晟

中臺科技大學/健康科學院/生命科學研究所/碩士(2012年)

摘要

肺癌治療中，肺癌細胞之EGFR (epidermal growth factor receptor )基因突變對於酪氨酸基酶抑制劑(tyrosine kinase inhibitor) 等標靶藥物之療效扮演著相當重要的角色。目前臨床之EGFR 基因 突變診斷以直接基因定序(direct sequencing)為標準方法，但其偵測的效能受限於突變細胞所佔的比例。比例需達25%以上，才可測得突變訊號。為了提高檢測率，本論文開發PNA (Peptide Nucleic Acid )-ZNA (Zip nucleic acids) Clamp PCR以應用於EGFR之突變檢測。此方法利用PNA 探針抑制野生型對偶基因之複製，並以ZNA探針針對突變型對偶基因進行專一性的增幅，以提升偵測靈敏度。突變的訊號則依TaqMan® Real-Time PCR 進行偵測。測試的結果顯示PNA-ZNA Clamp PCR 之偵測靈敏度可達0.1%(突變型/野生型)。在突變比例為1%時，只需1.56-4.16 ng 之模版DNA即可偵得突變訊號。此外，依據臨床檢體測試結果顯示，PNA-ZNA Clamp PCR 偵測突變之能力較DxS EGFR Mutation Test Kit 更佳。

關鍵字

肺癌

並列摘要

Mutations in the epidermal growth factor receptor (EGFR) gene are suggested to be strongly correlated with sensitivity to EGFR tyrosine kinase inhibitor, and play an important role in the targeted therapy for lung cancer. Nowadays direct sequencing is the gold standard for the detection of EGFR mutations, but its sensitivity is limited by the ratio of mutation cells in the specimen. Only when the percentage of tumor cells is above 25%, can direct sequencing detect mutations. To improve the detection efficiency, a novel method, PNA (Peptide Nucleic Acid )-ZNA (Zip nucleic acids) Clamp Clamp PCR, which was based on TaqMan® Real-Time PCR with the use of ZNA probes to amplify mutant alleles specifically and a PNA probe to block the amplification of wild type allele, was developed in this study. The experimental results demonstrated that PNA-ZNA Clamp PCR could increase the detection sensitivity to 0.1% (mutant allele/wild type allele). And when the ratio was 1%, 1.56-4.16 ng genomic DNA was sufficient for mutations detection. In addition, the clinical application assessment showed that PNA-ZNA Clamp PCR detection was more sensitive than DxS EGFR Mutation Test.

並列關鍵字

EGFR

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