Determination of breath isoprene in 109 suspected lung cancer patients using cavity ringdown spectroscopy

Background:Lung cancer is one of the most common malignant tumors worldwide.Currently,effective screening methods for early lung cancer are still scarce.Breath analysis provides a promising method for the pre-screening or early screening of lung cancer.Isoprene is a potential and important breath biomarker of lung cancer.Material and Methods:To investigate the clinical value of isoprene for diagnosing lung cancer patients,a cavity ringdown spectroscopy(CRDS)based near-real time,sensitive analysis method of breath isoprene is developed in our lab.In this paper,92 breath samples from lung cancer patients,17 breath samples from patients with benign lesions,and 107 breath samples from healthy people were collected.Results:Research indicates that breath isoprene concentration is significantly higher in healthy individuals(221:3±122:2 ppbv)than in patients with lung cancer(112:0±36:6 ppbv)and benign lung lesions(127:9±41:2 ppbv).The result of Receiver Operating Characteristic(ROC)curve suggests that the concentration of isoprene is meaningful for the diagnosis of lung cancer(AUC=0:822,sensitivity=63:6%,specificity=90:2%,P<0:01).Conclusion:This study demonstrates that the CRDS breath isoprene analysis system can effectively analyze a large sample of human breath isoprene,and preliminarily confirms the use of breath isoprene as a biomarker for lung diseases.

Early Diagnostic Value of Circulating MiRNA-21 in Lung Cancer: A Meta-Analysis

To evaluate the early diagnostic value of circulating miRNA-21 in diagnosis of lung cancer, databases such as Wan Fang, VIP, PubMed, and Elsevier were systematically searched from 2005 to 2013 to collect relevant references in which the diagnostic value had been evaluated. The statistics were consolidated and the qualities of the studies were classified. The data were analyzed using Meta Disc1.4 software. The diagnostic value of circulating miRNA-21 in lung cancer was assessed by pooling sensitivity, specificity, the likelihood ratio, and the Summary Receiver Operating Characteristic（SROC） curve. Publication biases of the studies involved were analyzed using Stata 11.0 software. A total of 143 papers were collected of which 8 were included, which contained 600 cases and440 controls. A heterogeneity test proved the existence of homogeneity in this study. Upon analysis using random effects models, the weighted sensitivity was 0.68, the specificity 0.77, the positive likelihood ratio 2.84, the negative likelihood ratio 0.40, and the SROC Area Under the Curve（AUC） was 0.8133. Further analysis by subgroup showed that the 5 indicators mentioned above were 0.72, 0.84, 4.50, 0.27, and 0.8987, respectively, for the serum group and 0.63, 0.70, 1.95, 0.53, and 0.7318, respectively, for the plasma group. We conclude that circulating miRNA-21can be regarded a valuable reference in diagnosis of lung cancer. This research showed that in lung cancer the early diagnostic value of miRNA-21 in serum was better than that in plasma.

Application of serum surface-enhanced laser desorption/ionization proteomic patterns in distinguishing lung cancer patients from healthy people

Screening and early diagnosis of lung cancer relies mainly on chest X-ray, low-dose computed tomography, bronchoscopy, sputum cytology, and measurement of tumor markers such as carcinoembryonic antigen (CEA), cytokeratin-19 fragments (Cyfra21-1), and neuron-specific enolase (NSE). However, all these methods lack adequate sensitivity and/or specificity. 1-3 Better methods are therefore urgently needed in screening and early diagnosis of lung cancer, and proteomic fingerprinting represents a promising approach. Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS), an innovative proteomic technology, has overcome many of the limitations of two-dimensional electrophoresis (2D) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). 4,5 Recently, this technology has been successfully used to distinguish pancreatic, ovarian and prostate cancer patients from healthy control subjects. 5-7 The aim of the current study was to investigate the application of serum SELDI protein profiling in distinguishing lung cancer patients from healthy persons.