Micrornas as Stable Circulating Biomarkers for Lung Cancer Diagnosis

Background: Lung cancer is the leading cause of cancer mortality in the world, but there are no satisfactory biomarkers for lung cancer detection. MicroRNAs are small non-coding RNAs that regulate the gene expressions at the posttranscription level. Many microRNAs are dysregulated and shows specific expression patterns in human cancer. The aim of this study is to profile circulating microRNAs in lung cancer patients and identify potential microRNA markers for lung cancer diagnosis. Method: Total RNAs from plasma of 5 non-small cell lung adenocarcinoma patients and 2 healthy volunteers were extracted and subjected to microRNA profiling with Illumina Human miRNA microarray. Microarray data were normalized with Global median and analyzed with One-Way ANOVA provided in Partek Genomics Suite. The microRNAs with significant higher level (p< 0.05 and fold change>4) in lung cancer patients were identified as marker candidates. Independent set of plasma samples (from 27 cancer patients and 27 volunteers) were used for validation of these markers with quantitative RT-PCR. Results: Principle Component Analysis (PCA) showed different profiles of plasma microRNA in lung cancer patients and healthy volunteers. Four microRNA candidates with higher level in lung cancer patients were identified. Further screening with clinical samples confirmed that the levels of two microRNAs, miR-148b* and miR-33a were significantly higher in lung cancer patients. Conclusion: Our results demonstrated that dysregulated microRNAs can be found in plasma of lung cancer patients and that these cancer-specific microRNAs may have potential to be used as diagnostic markers for lung cancer. MICRORNAS AS STABLE CIRCULATING BIOMARKERS FOR LUNG CANCER DIAGNOSIS Cheng-Chi Yen( )1, Chun-Liang Shih( )2, Chiuan-Chian Chiou( )1,2 1Department of Medical Biotechnology and Laboratory Science and 2Institute of Basic Medical Science Chang Gung University, Taiwan Background: Lung cancer is the leading cause of cancer mortality in the world, but there are no satisfactory biomarkers for lung cancer detection. MicroRNAs are small non-coding RNAs that regulate the gene expressions at the posttranscription level. Many microRNAs are dysregulated and shows specific expression patterns in human cancer. The aim of this study is to profile circulating microRNAs in lung cancer patients and identify potential microRNA markers for lung cancer diagnosis. Method: Total RNAs from plasma of 5 non-small cell lung adenocarcinoma patients and 2 healthy volunteers were extracted and subjected to microRNA profiling with Illumina Human miRNA microarray. Microarray data were normalized with Global median and analyzed with One-Way ANOVA provided in Partek Genomics Suite. The microRNAs with significant higher level (p< 0.05 and fold change>4) in lung cancer patients were identified as marker candidates. Independent set of plasma samples (from 27 cancer patients and 27 volunteers) were used for validation of these markers with quantitative RT-PCR. Results: Principle Component Analysis (PCA) showed different profiles of plasma microRNA in lung cancer patients and healthy volunteers. Four microRNA candidates with higher level in lung cancer patients were identified. Further screening with clinical samples confirmed that the levels of two microRNAs, miR148b* and miR-33a were significantly higher in lung cancer patients. Conclusion: Our results demonstrated that dysregulated microRNAs can be found in plasma of lung cancer patients and that these cancer-specific microRNAs may have potential to be used as diagnostic markers for lung cancer. Abstract