用傳統的檢查方法，冀望能早期診斷肺癌，以減低死亡率，一直沒有顯著的進展。近年來，由於分子腫瘤學的迅速發展，或許可以提供早期診斷肺癌的一個有效工具。p53基因突變是肺癌的腫瘤化過程中最常見的突變。由於傳統的痰抹片檢查方法，其敏感度很低，所以在本研究中，我們嚐試建立用聚合酉每連鎖反應的模式，評估從肺癌患者的痰細胞抹片中，早期偵測p53基因突變，而這些痰的檢體都是他們尚未被診斷肺癌以前所收集的。 我們很成功的從這十個痰抹片中，萃取出足量的RNA，並經由反轉錄酉每的作用，將它們做成cDNA，再藉由聚合酉每連鎖反應將之放大，最後做直接定序的檢查。 研究結果發現在十個痰抹片檢體中，可以測得出其中一位在p53的codon 286位置有基因突變。這結果顯示出從痰的細胞學抹片偵測p53基因突變對於肺癌病人早期診斷提供了一個可行的方法與策略。 ABSTRACT Little progress has been made in decreasing lung cancer mortality by applying conventional methods to early diagnosis and screening. Recent advances in molecular oncology, however, have provided tools which may be of use in this area. p53 gene mutation is the most common gene alteration in the development of lung cancer. Conventional cytologic analysis of sputum is an insensitive test for the diagnosis of lung cancer. In this study, we attempted to establish a polymerase chain reaction (PCR)-based assay for assessing the possibility of early detection of p53 mutation in archival Papanicolaou-stained cytologic sputum smears. Ten sputum smear slides were collected prior to clinical diagnosis from 10 lung cancer patients who has been confirmed to have p53 mutations in surgically resected lung tumors. We successfully obtained sufficient amounts of RNA from each sputum smear specimen for amplification of PCR and direct sequencing. Only one patient was found to have p53 mutation at codon 286; the other nine patients had wild type p53 genes. This result supports the possibility that detection of p53 mutations in cytologic sputum smears is an available strategy for the early diagnosis of lung cancer.
