癌症治療方法分為手術、放射線治療和化學治療，接受放射線治療的患者約佔 50%；台灣癌症登記報告中指出主要使用放射線治療的癌症為頭頸癌和大腸直腸癌。放射線治療雖然是有效的治療，但部分患者對此治療的反應效果不佳使癌症易復發。 微型核糖核酸（miRNA）藉由調控基因而影響癌症的生成機制。最近研究顯示miRNA 會參與DNA 損傷反應，此反應被報導與腫瘤對於放射線反應具有相關性；此外miRNA 被發現會存在於人的體液中且可作為預後生物標記，因而希望開發一個有效且快速便利的生物標記。此實驗使用先前研究已篩選出的候選miRNA，增加病人數並使用簡易的萃取RNA 方法以開發放射線治療的預後生物標記並研究候選miRNA 是否會影響頭頸癌細胞的放射線敏感性。 此研究收集經放射線治療前的頭頸癌和大腸直腸癌患者的血液並在治療完後追蹤六個月和一年的預後反應。即時定量系統偵測候選miRNA 表現量並由訓練集挑選出潛在標記；候選miRNA 表現量和臨床資料做多重邏輯斯回歸得到生物標記。六個月預後標記AUC為0.9083 (n=52)；一年預後標記AUC為0.8235 (n=49)。藉由細胞集落形成實驗證實miR-130a-3p 會增加頭頸癌細胞對放射線敏感性。 希望此研究在未來可以預測病人的放射線預後反應，提升病人預後效果；並深入了解miR-130a-3p 會如何調控放射線敏感性相關的機制。;Cancer treatments are commonly categorized into surgery, radiotherapy and chemotherapy. There are about 50% of cancer patients receiving radiotherapy. The Taiwan cancer registration reported that the majority of head and neck cancer and colorectal cancer patients were treated with radiotherapy. Radiotherapy is effective but a part of patients occurs radioresistance due to poor prognosis. microRNA (miRNA) is a non-coding RNA containing about 21-24 nucleotides, which affects cancer development by regulating post-transcriptional gene expression. Recent studies showed that miRNAs are involved in DNA damage responses (DDR), which has been reported to relate to tumor cell radiosensitivity or radioresistance. Furthermore, miRNA is found in human body fluids and can play as a prognosis biomarker. We hope to develop an biomarker with convenience and rapid, and this prognosis biomarker of radiotherapy can be applied in the clinic. Therefore, this study focused on several candidate miRNAs that have been found in previous study but more plasma samples from head and neck cancer and colorectal cancer patients were collected in this study compared to previous study. In addition, a novel simple RNA extraction protocol was applied in this study. We devoted to develop candidate miRNA expressions as the prognostic biomarker for radiotherapy and to study whether these candidate miRNAs can affect the radiation sensitivity of head and neck cancer cells. In this study, plasma samples were collected from patients of head and neck cancer and colorectal cancer before radiation treatment. These patients were tracked clinical responses after six months or one year of radiotherapy. These candidate miRNA expression levels were detected by real-time polymerase chain reaction (qRT-PCR). The miRNA combination ratios and clinical responses were developed to the classifier as the prognostic biomarker for radiotherapy by multiple logistic regression analysis. The area under the curve (AUC) of the classifier for the prediction after six-month of radiation was 0.9083 (n = 52). The AUC of the classifier for the prediction after one-year of radiation was 0.8235 (n = 49). In addition, we confirmed that miR-130a-3p increased radiosensitivity in head and neck cancer cells by colony formation assay. We hope the results of this research could be applied to predict the response of patients to radiotherapy and improve the survival of patients. We will devote to knowing how miR- 130a-3p regulates the DNA damage responses in the future.
