GENE EXPRESSION PROFILING IN MULTIDRUG RESISTANT KB CELLS USING cDNA MICROARRAYS

Objective: A single mechanistic pathway cannot explain the genesis of drug resistance in cancer. Drug resistance in cancer is a major obstacle to successful chemotherapy. KB cells provide a useful starting point for selection of the multidrug resistant (MDR) cell lines. Methods: We used cDNA microarrays containing 12,720 sequences of known genes, expressed sequence tags and unknown clones to monitor gene expression profiles in MDR KB cells. Results: Preliminary data analysis showed that 18 genes were up-regulated and 18 genes were down-regulated by comparison of expression patterns between KB 3-1 and MDR KB-V1 cells. Furthermore, the highly over-expressed CGA, CLU genes in MDR KB-V1 cell were verified with conventional Northern blot analysis. These genes contain information predictive of drug resistance of cancer cells. Conclusion: Our study demonstrates that genome-wide gene expression profiling by using cDNA microarray technique is a valuable approach in obtaining molecular mechanism of drug resistance in cancer cells.

超高速细胞分选平台结合cDNA microarray技术筛查宫颈癌细胞潜在分子标志物

目的:通过超高速细胞分选平台结合cDNA microarray技术,筛查宫颈癌细胞可能潜在的分子标志物。方法:采用MoFlo XDP型超高速细胞分选平台纯化细胞膜表面表达CD38和不表达CD38的宫颈癌细胞,利用RNAlater技术得到cDNA microarray实验所需RNA,然后进行基因芯片分析。结果:利用MoFlo XDP型超高速细胞分选平台可以获得纯度为99.0%以上的CD38阳性表达宫颈癌细胞。结论:cDNA microarray分析发现了RORA、PLIN4、AUTS2、IFITM1等宫颈癌细胞潜在分子标志物,为宫颈癌研究提供了新的技术方法。

Analysis of gene expression profiles in pancreatic carcinoma by using cDNA microarray

OBJECTIVES: To survey the gene expression profiles in pancreatic carcinoma by using cDNA microarray and detect target genes for further study. METHODS: Three mixed samples from 2 cases of normal pancreatic tissue and 4 cases of moderate-differentiated pancreatic carcinoma were studied by means of cDNA microarray consisting of 18 000 genes. RESULTS: 1484 and 1353 different expressed genes were observed in two cancer samples respectively. We identified 455 genes altered with the same tendency in both samples, including 102 up-regulated and 353 down-regulated genes. There were 274 known genes and 181 unknown genes; 27.8% and 52.0% genes respectively had an expression level in cancer that was 2-fold higher or lower than that in normal samples. Tumor suppressor genes, growth factors and receptor genes, signal conduction genes, transcription factor genes were identified. CONCLUSIONS: cDNA microarray is an efficient and high-throughout method to investigate gene expression profiles in pancreatic carcinoma. MBD1, EDG1 and gene hypermethylation mechanism would play an important role in the pathogenesis of pancreatic carcinoma.

Development of a Porcine cDNA Microarray:Analysis of Clenbuterol Responding Genes in Pig(Sus scrofa) Internal Organs

Pig （Sus scrofa） fat accumulation can be reduced by feeding with high dosages of clenbuterol, but the molecular mechanism has not yet been explained. In our study, a porcine cDNA microarray representing 3 358 pig genes was successfully developed. This microarray is the first porcine DNA microarray in China and its false positive rate is 0.98%, which means the microarray platform is reliable. The microarray can be used to study gene expression profiles in multiple pig tissues because the present genes percentage of adipose, skeletal muscle, heart, liver, lung, kidney, and spleen were all more than 60%. This microarray was used to identify the genes responding to clenbuterol stimulation in pig internal organs, including heart, liver, lung, spleen, and kidney. Many genes were identified including enzymes involved in lipids metabolism （lipoprotein lipase up-regulated in liver, heart and lung, ATP-citrate lyase and carnitine palmitoyltransferase II precursor up-regulated in liver, succinyl-CoA up-regulated in lung, mitochondrial malate dehydrogenase down-regulated in spleen）, and signaling pathway genes （cAMP-protein kinase A signaling pathway was found up-regulated in liver, heart, lung, and kidney as reported previously, while transforming growth factor was found down-regulated in heart and lung）. However, no common gene responding to clenbuterol administration was found in all tissues. The expression levels of 14 genes were analyzed using real-time PCR with 82.1% of them induced to express similar magnitudes as in the microarray analyses. This work offers some understanding of how clenbuterol so effectively reduces pig adipose accumulation on the molecular level.

Early Diagnosis of Epithelial Ovarian Cancer with cDNA Microarry

Objective： To investigate the roles of tumor suppressor genes- PTEN, nm23H1, VEGF165, Tiaml, MMP-2, Timp2, HE4 and S 100A4 in tumorigenesis and progression of epithelial ovarian cancer（EOC） and develop a novel method for the early diagnosis of EOC. Methods： We observed the different expression profiles of those genes in normal ovary（n=5） and ovarian cancer tissue （n=20） by cDNA microarray. Results： In EOC, PTEN, Timp2 and nm23Hl genes were down-regulated （CY-3/CY-5〈0.5）, compared with the normal ovary, whereas Tiaml, VEGFI65, MMP-2, HE4 and S100A4 genes were up-regulated （CY-3/CY-5〉2.0）. Among them, HE4 gene was remarkably elevated （CY-3/CY-5〉5.0）. Their expression was correlated with clinicopathological staging of EOC（P〈0.01）. Conclusion： Those genes are closely linked to the pathogenesis and progression of EOC. cDNA microarray is an effective technique to screen molecular biological markers and predict the metastastic potential of EOC in early diagnosis.

A cDNA microarray analysis of the molecular control of poplar wood properties

Molecular biological research into wood development and formation has been the focus in recent years, but the pace of discovery of related genes and their functions in the control of wood properties has been slow. The microarray technique--with its advantages of high throughput capacity, sensitivity, and reliability over other tools developed for investigating genes expression patterns-is capable of rapidly assaying thousands of genes. In this study, a cDNA microarray prepared from two cDNA libraries of developing poplar xylem tissues was used to assay gene expression patterns in immature xylem tissues at different heights from the main stem of Populus deltoides （15 years old）, which was confirmed to have distinct wood properties （microfibrillar angle, woody density） by X-ray. Two hundred seventy-four transcripts with differ- ential expression profles between the chips were screened out, and the individual clones were subjected to 5＇ sequencing. Using bioinformatic analysis, we identified candidate genes that may influence poplar wood properties, many of which belong to various regulatory and signal transduction gene families, such as zinc finger protein transcription factor, DNA-binding transcription factor, ethylene response factors, and so on. The results suggest that these genes may regulate enzymes involved in wood formation. Further work will be performed to clone these genes and determine how they influence poplar wood properties.

Gene expression in retinoic acid-induced neural tube defects A cDNA microarray analysis

BACKGROUND： Neural tube defects can be induced by abnormal factors in vivo or in vitro during development. However, the molecular mechanisms of neural tube defect induction, and the related gene expression and regulation are still unknown. OBJECTIVE： To compare the differences in gene expression between normal embryos and those with neural tube defects. DESIGN, TIME AND SETTING： A neural development study was performed at the Department of Neurobiology, Third Military Medical University of Chinese PLA between January 2006 and October 2007. MATERIALS： Among 120 adult Kunming mice, 60 pregnant mice were randomly and evenly divided into a retinoic acid group （n = 30） and a normal control group （n =30）. The retinoic acid was produced by Sigma, USA, the gene microarray by the Amersham Pharmacia Company, Hong Kong, and the gene sequence was provided by the Incyte database, USA. METHODS： Retinoic acid was administered to prepare models of neural tube defects, and corn oil was similarly administered to the normal control group. Total RNA was extracted from embryonic tissue of the two groups using a Trizol kit, and a cDNA microarray containing 1 100 known genes was used to compare differences in gene expression between the normal control group and the retinoic acid group on embryonic （E） day 10.5 and 11.5. Several differentially expressed genes were randomly selected from the two groups for Northern blotting, to verify the results of the cDNA microarray. MAIN OUTCOME MEASURES： Morphological changes and differential gene expression between the normal control group and the retinoic acid group. RESULTS： Anatomical microscopy demonstrated that an intact closure of the brain was formed in the normal mouse embryos by days E10.5 and E11.5. The cerebral appearance was full and smooth, and the surface of the spine was intact. However, in the retinoic acid group on days E10.5 and E11.5, there were more dead embryos. Morphological malformations typically included non-closure at the top of the cranium and abnormal changes of the metencephalon and face. cDNA microarray analysis suggested that the changes in expression of seven different genes were similar on both days E10.5 and E11.5. These were downregulation of NekT, Igfbp5, Zw10, Csf3r, Psmc6 and Rb 1, and upregulation of Apoa-4. This study also indicated that Cdk5 expression was downregulated in the retinoic acid group on day E11.5. The results of the cDNA microarray analysis were partly confirmed by Northern blotting. CONCLUSION： Cdk5, Nek7, Igfbp5, Zw10, Csf3r, Psmc6, Rb1 and Apoa-4 may be key factors in retinoic acid-induced neural tube defects.

GENE EXPRESSION PROFILING OF GANGLIOGLIOMA MALIGNANT PROGRESSION BY cDNA ARRAY

Objective: To establish gene expression profiles associated with malignant progression of ganglioglioma. Methods: The primary and two recurrent glioma specimens were collected intraoperatively from the same patient who experienced tumor transformation into anaplastic astrocytoma and glioblastoma multiform for the first and second recurrence respectively. Gene expression was assayed through cDNA array and bioinformatics analysis. Results: A total of 197 differentially expressed genes with differential ratio value more than 3 compared with normal brain tissue were obtained. Among 109 functionally denned genes, those associated with development ranked the first by frequency, followed by genes associated with metabolism, differentiation, signal transduction and so on. As a result of cluster analysis among 368 genes, eleven genes were up regulated with malignant progression, while six genes were down regulated. Conclusion: Gene expression profiles associated with malignant progression of glioma were successfully established, which provides a powerful tool for research on molecular mechanisms of malignant progression of gliomas.

Gene Expression Patterns in Different Wool Densities of Rex Rabbit Using cDNA Microarray

This study was carried out to identify gene expression patterns in different wool densities of rex rabbit. The mid-dorsal skin samples from 8 rex rabbits were studied. They were divided into two groups according to different wool densities. Total RNA was isolated and labeled by reverse transcription reaction with Cy5-dCTP and Cy3-dCTP for cDNA probe. The cDNA probe was hybridized with cDNA microarrays containing 14 601 rabbit’s genes. The differently expressed genes were analysed with the Gene Ontology （GO） classification and the pathway analysis. Hierarchical clustering was performed to clarify genes in association with different wool densities. The 2 657 differentially expressed genes were identified. Among them, 1 103 genes were functionally known genes, 687 genes were up-regulated and 419 were down-regulated. GO analysis indicated that these altered genes were associated with metabolism, signal transduction, cell cycle, cell adhesion, cell proliferation, cell division, apoptosis, and other processes. KEGG analysis showed that 95 signal pathways associated with up-regulated genes and 87 signal pathways associated with down-regulated genes had changed significantly （P0.05）. Some important differentially expressed genes in different wool densities of rex rabbit were identified, such as MMP2, TGF-β1, TGF-β2, IGF-1, ITGB1, RPS6KB1, BMP2, ActRIIB, CDK2, and CCNA2. Hierarchical clustering analysis separated the differentially expressed genes into 5 main characteristic groups. Data from cDNA microarray experiments clearly distinguished between group A and group B. Some important genes were identified, which might be useful in further study on wool density markers of rex rabbit.

Monitoring the Expression Profiles of Cereal Crops Seedlings by Using Rice cDNA Microarray

Through exploiting the high homology of cereal crop genes, membranous cDNA microarrays containing 3 311 unique rice transcripts (including 1 639 endosperm-derived transcripts and 1 672 mature stem-derived transcripts) were used for monitoring the expression profiles of 1-leaf stage seedlings of 4 cereal crop species: rice, maize, sorghum and barley. After hybridizing with [α-33P| labeled probes, 73.6 % of the arrayed genes generated reliable signals in all of the four cercal crops. Further analysis revealed that among the arrayed genes, a higher percentage of the endosperm-derived transcripts (86.6 %) expressed than that of the mature stem-derived genes (60.9 %), indicating that most of the endosperm expressed genes functioned in young seedlings while considerable amount of mature stem tissue expressed genes did not express. These results also inferred that some genes might function only at certain developmental stages. By comparing the obtained profiles, 84 genes were identified constantly expressed in all me four cereal crops. Many housekeeping genes, such as polyubiquitin, ubiquitin conjugating enzyme and ribosomal proteins were included in this catalogue. The experiment also identified 14 rice seedling specifically expressed genes, including 3 biotic and abiotic stress induced genes and 1 apoptosis suppressor encoding gene Bax inhibitor-1. This investigation provided invaluable information for comparative genomics of gramineae members.

LD-RTPCR:A NEW METHOD FOR LABELLING TRACE cDNA MICROARRAY PROBE

Objective: To explore the usefulness of long distance reverse transcript combining linear amplification (LD-RTPCR) in labeling slight trace probe used for cDNA microarray. Methods: Total RNA from BEP2D cells was extracted and labeled by two different methods, LD-RTPCR with Cy3-dCTP as fluorescent dye and traditionally used RNA reverse transcript (RT) with Cy5-dCTP as fluorescent dye. Then, the probes labeled by two methods were mixed equally and hybridized with the cDNA microarray. Results: Scan and analysis of the microarray showed that the two methods labeled probes had consistent results. Conclusion: LD-RTPCR was proved useful for labeling cDNA microarray probe, especially for limited RNA material.

cDNA Microarray Analysis of Insulin Resistance-associated Genes in Fructose-fed Rats

This study was conducted to investigate the gene expression in fructose-fed rat skeletal muscle by cDNA chip which could provide support to elucidate the molecular mechanisms underlying insulin resistance. The rats were divided into two groups, one of which was normal control and the other was fed with fructose-rich diet. The mRNA was isolated and purified from the skeletal muscle of two groups. The mRNA from two kinds of tissue was reverse transcribed to cDNA with Cy3-dUTP and Cy5-dUTP separately to prepare hybridization probes. The mixed probes were hybridized to cDNA microarray. The microarray was scanned, analyzed and repeated for two times. Among the total 4 096 tested genes, 140 genes were differently expressed, 62 up-regulated,78 down-regulated, the expression of Ptprd and Gilz and multiple genes of oxidative metabolism is associated in insulin resistance. The differential expression of gene may be related to the pathogenesis of insulin resistance.

Study on Wusan Granule Anti-tumor Related Target Gene Screened by cDNA Microarray

To screen Wusan Granule anti-tumor related target gene using cDNA microarray technique, both mRNA from Lewis lung carcinoma tissues treated by Wusan Granule and untreated control are reversibly transcribed to prepare cDNA probes which are labeled by Cy5 and Cy3. Then, the probes are hybridized to the mice cDNA microarray type MGEC-20S. After hybridization, the cDNA microarray is scanned by ScanArray 3 000 scanner and the data is analyzed by ImaGene 3 software to screen the differentially expressed genes. There are 45 differentially expressed genes including 18 known genes and 27 unknown genes between the two groups, and among them, 20 elevated genes and 25 reduced genes are identified. Additionally, the genes related to invasion and metastasis of malignant carcinomas are down-regulated and the genes related to apoptosis are up-regulated. The cDNA microarray technique is a high-throughput approach to screen the Wusan Granule anti-tumor related target genes, which allow us to explore the molecular biological mechanism on a genomic scale.

AnalysisofdifferencesofgeneexpressionsinkeloidandnormalskinwiththeaidofcDNAmicroarray

Background:Microarray analysis is a popular tool to investigate the function of genes that are responsi-ble for the phenotype of the disease.Keloid is a intricate lesion which is probably modulated by interplay of manygenes.We ventured to study the differences of gene expressions between keloids and normal skins with the aid ofcDNA microarray in order to explore the molecular mechanism underlying keloid formation.Methods:The PCRproducts of 8400 human genes were spotted on a chip in array.The DNAs were t...

Screening of differentially expressed genes related to differentiation and proliferation by gene expression profiling of different grade astrocytoma cell lines

BACKGROUND： The detection of differential gene expression in brain is possible by cDNA microarray technology, and the screening of differentially expressed genes might provide a biological basis for gene-targeted therapy for tumors. OBJECTIVE： To detect the differential expression of genes among astrocytoma SHG-44 （WHO grade Ⅳ）, CHG-5 （WHO grade Ⅱ）, and ATRA-treated SHG-44 cell lines by cDNA microarray. DESIGN： Laboratory experiments in vitro. SETTING： Department of Neurobiology, the Third Military Medical University. MATERIALS： The experiment was performed at the Department of Neurobiology in the Third Military Medical University of the Chinese PLA from January to October 2007. The SHG-44 cell line （WHO grade Ⅳ） was established by Prof. Ziwei Du, and the CHG-5 cell line （WHO grade Ⅱ） was set up by Prof. Xiuwu Bian from the Third Military Medical University of the Chinese PLA. The cDNA microarray containing 9182 known genes was prepared and provided by Dr. Yang Zhong at the City University of Hong Kong. METHODS： To screen differentially expressed genes from the gene expression profiles detected by cDNA microarray comparisons were made between CHG-5 and SHG-44 cells and between SHG-44 cells with or without treatment with 10 μmol/L ATRA. Some differentially expressed genes were selected randomly for Northern Blot analysis to confirm the results of the microarray. The determination criteria for differential gene expression were as follows. ① The ratio of Cy5 signal to Cy3 was greater than 2.0 or less than 0.5. ② The results of the triplicate microarray hybridizations showed the same trend in three experiments. ③ A gene appeared at least two times on the triplicate microarray hybridizations, and the 3^rd value did not show a contradictory trend. A normalized ratio of Cy5 intensity to Cy3 greater than 2.0 or less than 0.5 was considered to represent up-regulated or down-regulated gene expression, respectively. MAIN OUTCOME MEASURES： The identification of genes that were similarly regulated （overlapping） during tumor progression and differentiation, by comparison of gene expression profiles between CHG-5 and SHG-44 cells, and between SHG-44 cells with or without treatment with ATRA. RESULTS： Thirty-one overlapping genes were found to have similar regulatory effects on astrocytomas; among them, twenty genes were up-regulated and eleven were down-regulated in both comparisons between CHG-5 and SHG-44 cells, and between SHG-44 cells with or without treatment with ATRA. The four reported genes, SERPINFI, MAPKI 1, HIFIA and SOD2, were up-regulated in this study. CONCLUSION： The differentially expressed genes in different grade astrocytoma cell lines were revealed primarily by cDNA microarray; among them, five identified overlapping genes, SERPINF1, MAPK11, DCTN2, HIF1 A and SOD2, were related to the malignant progression of astrocytoma cells.

Expression and significance of Rap1A in testes ofazoospermic subjects

Aim: To evaluate the Rap1A mRNA expression and its significance in the testes of normal and azoospermic subjects. Methods: A cDNA microarray that contained Rap1A and some other genes such as RBM, EIF1 AY was used to identify the differential gene expression profiles between the normal and azoospermic testes. cDNA probes were prepared by labeling mRNA from azoospermic and normal testicular tissues through reverse transcription with Cy5-dUTP and Cy3-dUTP, respectively. The mixed cDNA probes were then hybridized with cDNA microarray (each containing 4096 unique human cDNA sequences). The fluorescent signals were scanned and the values of Cy5-dUTP and Cy3-dUTP on each spot were analyzed and calculated. In situ hybridization was employed to detect the expression of RaplA in the testes of 10 fertile and 39 azoospermic subjects. Results: One hundred and twenty-eight differentially expressed genes were found to be possibly related to azoospermia, of which 56 were up-regulated and 72, down-regulated genes. The mRNA expression of RaplA in the spermatogenic cells of azoospermic was stronger than that in those of the fertile testes. Conclusion: Rap1A may play certain roles in the development of azoospermia.

GENE EXPRESSION PROFILING OF HUMAN PROMYELOCYTIC LEUKEMIA HL-60 CELL TREATED BY AJOENE

Objective: Ajoene, a major compound extracted from crashed garlic, has been shown to have antitumor, antimycotic, antimicrobial, antimutagenic functions in vivo or in vitro and treated as a potential antitumor drug. However, the molecular mechanisms underlying the tumor cytotoxicity of ajoene and even garlic substances are poorly defined. In the present study, we aimed to generate gene expression profiles of HL-60 cell treated by ajoene. Methods: A cDNA microarray presenting 2400 of genes amplified from human leukocyte cDNA library was constructed and the gene expression profiles of HL-60 cell induced by ajoene were generated. Results: After data analysis, 28 differentially expressed genes were identified and sequenced. These genes include 21 known genes and 7 ESTs. Most of the known genes are related to cell apoptosis, such as secretory granule (PRG1), beta-2 microglobulin (B2M), 16S ribosomal RNA gene and ribosomal protein S12. Several genes are related to cell differentiation, including the genes similar to H3 histone and ribosomal protein L31. Northern blot analysis was used to verify and quantify the expression of selected genes. Conclusion: Ajoene can induce HL-60 cell apoptosis significantly and may play a role in differentiation. cDNA microarray technology can be a valuable tool to gain insight into molecular events of pharmacological mechanism of herbal medicine.

Expression of a novel pyridoxal kinase mRNA splice variant,PKH-T, in human testis

Aim: To identify the genes specifically expressed in human adult and fetal testes and spermatozoa. Methods: A human testis cDNA microarray was established. Then mRNAs of human adult and fetal testis and spermatozoa were purified and probes were prepared by a reverse transcription reaction with mRNA as the template. The microarray was hybridized with probes of adult and fetal testes and spermatozoa. The nucleic acid sequences of differentially expressed genes were determined and homologies were searched in the databases of GenBank. Results: A novel human testis-specific gene, PKH-T, was identified by hybridizing adult and fetal testis and spermatozoa probes with a human testis cDNA microarray. The cDNA of PKH-T was 1 069 bp in length. The cDNA sequence of this clone was deposited in the Genbank (AY303972) and PKH-T was also determined as Interim GenSymbol (Unigene, HS.38041). PKH-T contained most PKH conserved motif. The 239 amino acid sequences deduced from the 719 bp open reading frame (ORF) had a homology with the gene PKH (U89606). PKH-T was specifically and strongly expressed in the testis. Comparison of the differential expressions of PKH and PKH-T in testes of different develop-mental stages indicated that PKH-T was expressed in the adult testis and spermatozoa, while PKH, in the adult, fetal and aged testes. PKH-T had no expression in the testis of Sertoli cell only and partially spermatogenic arrest patients. Conclusion: PKH-T is a gene highly expressed in adult human testis and spermatozoa. It may play an important role in spermatogenesis and could be related to male infertility. (Asian J Androl 2004 Jun; 6: 83-91)

Identification of tumor invasion-related differentially expressed genes in different grades and all-trans retinoic acid-treated astrocytoma cell lines

BACKGROUND： Although several genetic aberrations and gene expressional changes have been shown to exist in tumors and different grades of astrocytomas, as well as in normal tissues, the gene profiling and genetic pathways associated with malignant transformation and progression remain unclear. OBJECTIVE： To identify differentially expressed genes related to tumor invasion from various grades and all-trans retinoic acid （ATRA）-treated astrocytoma cell lines by cDNA microarray. DESIGN, TIME AND SETTING： In vitro gene experiment was performed at the Department of Neurobiology, Third Military Medical University of Chinese PLA from January to October 2007. MATERIALS： Two different grades of astrocytoma cell lines CHG-5 （WHO grade II ） and SHG-44 （WHO grade IV） were developed by our laboratory; a cell differentiation-inducing agent ATRA and a human cDNA microarray technology were used to determine differentially expressed genes （City University of Hong Kong）. METHODS： Total RNA was extracted using the Trizol test kit. Reverse transcription was performed using Superscript 11 reverse transcriptase. The cDNA product （target DNA） was marked with fluorochromes Cy3 （normal SHG-44） and Cy5 （CHG-5 or ATRA-treated SHG-44）, followed by chip hybridization. MAIN OUTCOME MEASURES： Gene expression profiles of CHG-5 vs. SHG-44 and ATRA-treated vs. normal SHG-44 were performed to identify differentially expressed genes. Several of these genes were randomly selected for Northern Blot analysis. The identification of genes that were similarly regulated （overlapping） was performed by comparing gene expression profiles between CHG-5 and SHG-44 cells, and between SHG-44 cells with or without treatment with ATRA. RESULTS： No significant differences were observed between CHG5 and SHG-44 cell line morphology. Under confocal microscopy, GFAP staining intensity of CHG5 cells was greater than SHG-44 cells （t = 6.078 P = 0.004）. Growth curve analysis demonstrated that the speed of SHG-44 cell growth was greater than CHG5 cells. Flow cytometry analysis showed that the number of ATRA-treated SHG-44 cells at G0/G1 stage increased by 15%, compared with normal SHG-44 cells （P 〈 0.05）. A total of 31 known genes with altered expression were identified in this study. Among them, 20 genes were upregulated and 11 were downregulated in CHG-5 compared with SHG-44 cells, and ATRA-treated SHG-44 compared with untreated SHG-44 ceils. Four of these reported genes （CD151, G3BP, UGB, and CSTB） were shown to be involved in tumor invasion. Validation of a selection of differentially expressed genes was perfonlaed by Northern blot. CONCLUSION： A total of 31 known genes were demonstrated by cDNA microarray to relate to the malignant progression of astrocytomas, and four differentially expressed genes （CD151, G3BP, UGB, and CSTB） were shown to relate to tumor invasion.