应用MALDI-TOF-MS检测肺鳞癌患者血清多肽并分析其与化疗疗效相关性

背景与目的 晚期肺鳞癌(squamous cell carcinoma of lung,SCC)一线治疗以化疗为主,其标准铂二联方案化疗只能给患者带来有限的获益.并且不同的患者对于化疗药物的获益不同.所以实现化疗药物最优选择达到个体化预见性治疗尤为重要.本研究应用基质辅助激光解析电离飞行时间质谱(matrix-assisted laser desorp-tion/ionization-time of flight-mass spectrometry,MALDI-TOF-MS)检测初治晚期SCC患者接受紫杉醇类联合铂类化疗前血清多肽,并分析其与化疗疗效的相关性.方法 初治晚期SCC患者接受紫杉醇类联合铂类方案化疗,每两周期进行疗效评价.评效为完全缓解(complete response,CR)或部分缓解(partial response,PR)患者定义为化疗敏感组,疾病进展(progressive disease,PD)患者定义为耐药组.留取SCC患者化疗前血清样本,81例患者按照3:1的比例随机分为训练组(敏感组I与耐药组I)和验证组(敏感组II与耐药组II),预处理训练组血清样本并进行MALDI-TOF-MS检测,得到血清多肽指纹图谱.经ClinProTools软件系统分析处理,得到敏感组I与耐药组I的差异多肽.应用软件内置的3种不同的生物学算法分别建立疗效预测模型,选取最优算法建立疗效预测模型.运用验证组进行盲样验证.结果 训练组共纳入30例敏感组患者,31例耐药组患者;验证组共纳入敏感与耐药组患者各10例.训练组在敏感与耐药组有96个差异多肽,其中具有统计学意义的多肽有16个(P<0.001).由5个多肽(1,897.75 Da,2,023.93 Da,3,683.36 Da,4,269.56 Da,5,341.29 Da)建立疗效预测模型.该模型对化疗敏感组患者的识别率为95.11%,交叉验证率为89.18%.经验证组进行盲样验证,其模型的准确率为85%,灵敏度为90.0%,特异性为80.0%.敏感组I中位无进展生存期(progress free survival,PFS)为7.2个月(95%CI:4.4-14.5);耐药组I中位PFS为1.8个月(95%CI:0.7-3.5).结果发现:4,232.04 Da、4,269.56 Da的差异多肽与SCC患者PFS存在相关性(P<0.001).结论 应用MALDI-TOF-MS技术可检测到化疗敏感组及耐药组患者的血清多肽存在差异,初步建立的疗效预测模型可用于预测紫杉醇类联合铂类方案化疗疗效.但需进一步扩大样本量完善及验证模型.

Detection of Serum Peptides in Patients with Lung Squamous Cell Carcinoma by MALDI-TOF-MS and Analysis of Their Correlation with Chemotherapy Efficacy

Background and objective Treatment options for patients with squamous cell carcinoma of the lung (SCC) are limited in chemotherapy. However, not all patients could benefit form standard platinum regimen. Considering the dismal prognosis of patients with advanced SCC, a greater focus on selecting sensitive chemotherapy regimens remains of up-most importance to improve outcomes in this disease. In this study, we used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to detect pre-chemotherapy serum peptides in advanced lung squamous cell carcinoma patients accepting paclitaxel combined with platinum chemotherapy and to analyze the correlation between serum peptides and che-motherapy efcacy. Methods Patients with advanced lung squamous cell carcinoma received paclitaxel combining with plati-num chemotherapy and evaluated the efcacy every two cycles. Evaluation of complete response (CR) or partial response (PR) patients defined as sensitive group, progressive disease (PD) patients defined as resistant group. Serum samples were collected from patients with lung squamous cell carcinoma. Eighty-one patients were randomly divided into training group (sensitive group Ⅰ and resistant group Ⅰ) and validation group (sensitive group Ⅱ and resistant group Ⅱ) according to the ratio of 3:1. Se-rum samples were pretreated and Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used to detect serum peptide fingerprints. ClinProTools software was used to analyze the differences between the sensitive group Ⅰ and the resistant group Ⅰ. Three kinds of biological algorithms (SNN, GA, QC) built in CPT software were used to establish the curative effect prediction model respectively and the optimal algorithm was selected. The validation group was used for blind verification. Results Thirty sensitive patients and 31 resistant patients were enrolled in the training group. Ten sensitive patients and 10 resistant patients were included in the validation group. The training group had 96 differentially expressed peptides in the sensitive and resistant patients, with 16 statistically significant peptides (P<0.001). The predictive model was established by 5 polypeptides (1,897.75 Da, 2,023.93 Da, 3,683.36 Da, 4,269.56 Da, 5,341.29 Da). The recognition rate of this model was 89.18% and the cross validation rate was 95.11%. The accuracy of the model was 85%, the sensitivity was 90.0% and the specificity was 80.0%. The median PFS in the sensitive group was better than patients in the resistant group (7.2 months 95%CI: 4.4-14.5 vs 1.8 months 95%CI: 0.7-3.5). The results showed that the differential peptides 4,232.04 Da and 4,269.56 Da were correlated with PFS in patients with lung squamous cell carcinoma (P<0.001). Conclusion MALDI-TOF-MS was used to detect the difference of serum peptides between sensitive and resistant groups. The preliminary curative effect prediction model was used to predict the efcacy of paclitaxel combined with platinum regimen. However, this model need further investigations to verify the accuracy and the sensitivity.