| Abstract: | 非小細胞肺癌在全世界及台灣都是發生率佔前五名，致死率第一名的癌症；目前鉑金類藥物搭配第三代化療藥，包括pemetrexed及taxane類藥物之雙重療法為建議之非小細胞肺癌第一線治療。而在我們的團隊中發現，使用pemetrexed加上cisplatin作為第一線治療的病患，雖然腫瘤不像taxane類藥物加上cisplatin治療時會有顯著的減小，但有較少的副作用、較好的生活品質及較長的存活期。而在這個現象背後的分子機轉還沒有被全面性的探討過。在此我們使用蛋白質體學的手法，包括膜蛋白萃取技術、iTRAQ定量技術及逆向Stage-Tip層析，最後使用液相層析串聯質譜儀分析非小細胞肺癌病人之周邊血單核球。
1850, 2093及2166個蛋白質在三個實驗中從六個病人當中被分析出來，四個病人為接受pemetrexed搭配cisplatin療法及兩名病人為接受taxane搭配cisplatin療法。分析四個pemetrexed治療病人有相同調控的蛋白質得到這些蛋白質可能與血小板活化、細胞附著及免疫反應有關；而用同樣的手法分析兩個taxane治療病人得到能與蛋白質轉譯及下降的免疫反應有關。比較腫瘤復發存活期特別長的病人及特別短的病人發現，存活期特別短的病人身上發現上升的CD3, CD4, CD45, MHC class II接受器, LCK及PI3K分子，可能和上調的表意反應有關；而在存活期特別長的病人上得到上升的CD3及CD4，下調的CD45、ZAP70及PI3K，顯示一個較平較平衡的免疫狀態。另外在EGFR突變接受taxane治療的病人身上偵測到下降的MHC class I和II及integrin分子，暗示免疫反應在這樣病人的下調。由本次研究中發現許多從未被發表過化療藥物對病人單核球細胞的影響，形成新的假說值得作進一步的探討。
Non-small-cell lung cancer (NSCLC) is the most common type of lung cancer worldwide. Currently, pemetrexed, combining with casplatin, has been used as the first-line treatment for patients carrying wild-type EGFR with locally advanced or metastatic NSCLC. Taxanes are another commonly used drugs for chemotherapy. Our team found that patients received pemetrexed treatment showed better clinical outcome and survival rate; however, the underlying perturbed mechanism has not yet been examined in the proteomic scope of view. To unravel the perturbed mechanism upon pemetrexed and paclitaxel treatment, we performed membrane proteomics analysis on patient’s purified peripheral blood mononuclear cells (PBMCs) by iTRAQ labeling, reversed-phase StageTip fractionation and LC-MS/MS analysis.
1850, 2093 and 2166 membrane proteins were identified in three sets of experiments from 6 patients’ PBMCs. Four of them were treated by pemetrexed plus cisplatin first-line treatment while two of them were treated by taxane plus cisplatin first line treatment. The molecular function analysis of the 120 and 44 proteins that had common expression profile in at least three patients in pemetrexed group and all two taxane treated patient respectively were conducted. Platelet and integrin activating functions were enriched in pemetrexed group and increased transcription activities were over-represented in taxane group. Immunophenotyping and pathway analysis results correlating with the clinical outcomes suggested that increased CD45RA, CD3, MHC class II molecule and unchanged integrins after first line treatment might suggest a disrupted immune status and linking to unfavorable outcomes. Up-regulated CTLA4 and integrin levels but unchanged CD45RA, CD3, MHC class II molecule after first line treatment might predict favorable effects. These new hypotheses are worth further investigation in more eligible patients. |
