Investigation Of Oligo-chip Related Molecular Classification Of Lung Cancer On The Basis Of Individual Therapy

Objection: To identify genes that relate the molecular classification of lung cancer, we developed an oligo-chip on the basis of individual therapy.Method: (1)Based on extensive literature search and our experimental results, 332 genes related to lung cancer genotyping, staging, drug-resistance and diagnosis were selected and designed as probes by the software with the length of 60bp. These oligonucleotide probes were spotted by microarrayer onto the amination modified glass slides, composing 4 blocks with 18×17 matrix;(2)Total RNA of 95D cell and tissues of lung adenocarcinoma and squamous cancer was isolated and reversely transcribed into cDNA with the incorporation of cy3 or cy5-labeled dUTP;(3)Fluorescently-labeled cDNA were hybridized with the oligo-chip. Fluorescence signals were scanned by ScanarrayLite laser scanner and farther analyzed by GeneSpring 5.1 software. The difference of gene expression was judged by the ratio of fluorescence intensity. Meanwhile, clustering methods was used to analyze the correlation of the gene expression profiles of lung adenocarcinoma and squamous cancer.Result: (1)The reliability of the chip technique: 332 oligonucleotide probes was spotted in the chip and divided into 4 blocks. Every block has 5 negative control genes. The low expression of negative control gene by hybridization proved the reliability of data;(2)The repeatability of the chip: the replicative experiments in 95D cell demonstrated >98.2% repeatability of the chip;(3)The consistency of the expressions of 332 genes in 7 samples of lung adenocarcinoma and 8 tissues of lung squamous cancer were 52-92% and 55-97%, respectively;(4)In our experiment results, the expressions of 29 genes were different in 7 tissues of lung adenocarcinoma comparing with lung squamous cancer. In 8 samples of lungsquamous cancer, there were 46 genes with different expression quantity comparing with lung adenocarcinom;(5)The freshly cut lung cancer tissues and paired normal tumor-adjacent tissues of the same patients (n=2) were collected. The up-expression was discovered genes that include s pro-alpha-1 type 3 collagen. TP,et al.And down-expression genes that CK19, PAI-1, wnt-4, et al.Conclusion: (1)The oligonucleotide chip method presented here for lung cancer genotyping is a rapid, accurate, sensitive and attractive high throughput biochemical way.(2)According to the results of our experiment, DCTN2, Stst2, CENPM represent lung adenocarcinoma, and CCT6A, HMGB2, EEF1A1 may be representative in lung squamous cancer.(3 )There were 22 genes that expressed in not only lung adenocarcinoma but also lung squamous cancer.This truth illuminated that cells of these tumor had similar biological behaviors.(4)In addition, the genes with different expression quantity in homoplastic tumor suggest that subgroups exist in lung adenocarcinoma and lung squamous cancer.