| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Advances in Brief |
Cancer Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, Maryland 20892
| ABSTRACT |
|---|
|
|
|---|
| Introduction |
|---|
|
|
|---|
70% of GISTs, can also be found in mesenchymal cells within the gut wall (1
, 2)
. A large proportion of GISTs are characterized by mutations in the KIT gene, predominantly in exon 11, which cause ligand-independent activation of its tyrosine kinase function and capacity to induce malignant transformation in vitro (1
, 4)
. Remarkably, the tyrosine kinase inhibitor STI571, which is active against the BCR-ABL fusion protein in CML, was recently shown to be highly effective in GISTs (5, 6, 7)
. To better understand the molecular basis of GIST tumorigenesis, we determined the gene expression profile of GIST, using 13,826-element cDNA microarrays. | Materials and Methods |
|---|
|
|
|---|
|
IHC.
We performed IHC with a rabbit polyclonal anti-KIT (CD117) antibody (A-4502, 1:50 dilution; DAKO Corporation, Carpinteria, CA) on paraffin-embedded tissue sections, using the avidin-biotin-peroxidase complex method (ABC Kit; Vector Laboratories, Burlingame, CA). To increase specificity and sensitivity, we used microwave antigen retrieval and an overnight incubation at 4°C with KIT.
cDNA Microarrays and Image Analysis.
The 13,826 human cDNAs used in this study were obtained under a Cooperative Research and Development Agreement with Research Genetics (Huntsville, AL). Gene names are according to build 138 of the Unigene human sequence collection.4
PCR products generated from these clones were printed onto glass slides as described previously (11)
. Microarrays were hybridized and scanned, and image analysis was performed as described previously (12
, 13)
. Briefly, fluorescently labeled cDNA was synthesized from
90 µg of tumor RNA or
45 µg of cell line RNA by oligo(dT)-primed polymerization in the presence of Cy3 or Cy5 dUTP, respectively (Amersham Pharmacia Biotech, Piscataway, NJ). The reference cell line was included in each hybridization to allow for normalization of each clones expression relative to the reference for each sample. Image analyses were performed with DeArray software (13)
.5
The two fluorescent images (red and green channels) obtained constituted the raw data from which differential gene expression ratio values were calculated. All data were entered into a database, using Filemaker Pro software.
Statistical Analyses.
The hierarchical clustering analyses and the MDS plot were generated as described previously (14
, 15)
. To filter the data set and select genes significantly expressed in GISTs, we required the average natural logarithm (ln) of the relative red (tumor) intensity (16)
for the mutation positive samples to exceed ln(1.5) for each clone. The genes were ranked according to the signal-to-noise ratio, and a weighted list of genes was generated as follows (17)
: Let [µ+(g),
+(g)] and [µ-(g),
-(g)] denote the means and SDs of the natural logarithm of the expression levels (calibrated ratios) of the gene g in the samples from mutation-positive GISTs and spindle cell tumors, respectively. The weight for each gene is defined as: w(g, ±) = |µ+(g) - µ-(g)|/[
+(g) +
-(g)]. When [µ+(g) -µ-(g)] is positive, the gene g is more highly expressed in the mutation-positive group, whereas when it is negative, the gene g is more highly expressed in the spindle cell group. A random permutation test was used to determine whether a gene was significantly associated with distinguishing the two classes. We randomly permuted the labels of the samples 100,000 times and for each gene calculated the probability
of obtaining a larger weight for a random permutation than for the separation of the two groups.
| Results and Discussion |
|---|
|
|
|---|
|
|
ln(1.5) to select for genes having a significant expression in GISTs. This requirement yielded a list of 1987 cDNAs (available on-line at the National Human Genome Research Institute web site5
). These genes were ranked to generate a weighted gene list (17)
, and a random permutation test was used to determine how many top-ranked genes significantly distinguished the two classes. We used
, the probability of a larger weight for a random permutation than for separation of GISTs versus spindle cell tumors, to assess the most significant discriminatory genes. We found 113 cDNAs with
0.0001. These 113 clones represented 77 unique cDNA sequences from 69 different genes (Fig. 3)
|
(PRKCQ) were highly expressed in GISTs and clustered tightly with KIT. Both G-protein-coupled receptors and protein kinase C are suggested as mediators of tyrosine kinase function (19)
, which suggests a possible relationship of PRKCQ and GPR20 to the KIT pathway. Genes encoding ion channels that were highly expressed in GISTs included the potassium channel genes KCNK3 and KCNH2. We also detected expression of the gene encoding secretogranin II (SCG2), the precursor of the neuropeptide secretoneurin, which is suggested to have a role in modulation of gastrointestinal motility (20)
. We believe that these observations together support the hypothesis that GISTs originate from a stem cell with the ability to differentiate toward an ICC phenotype (3
, 4)
. We also found uniform and high expression of the gene encoding tumor necrosis factor receptor subfamily 6b (TNFRSF6B), also known as DcR3 or M68, which recently was shown to be overexpressed in gastrointestinal adenocarcinomas (21)
.
Traditional immunohistochemical staining patterns of GISTs show CD34 positivity in
70% of the tumors, which helps narrow the differential diagnosis of GIST from other mesenchymal tumors (1
, 3)
. Our cDNA array data showed high expression of CD34 mRNA in 9 of our 13 studied tumors (data not shown), a proportion in total agreement with previous observations. The CD34 gene was the 376th discriminator on our weighted list (weight, 0.9;
0.008).5
One striking observation is the remarkable consistency of the gene expression pattern within the GIST group. When we applied hierarchical clustering (14
, 15)
based on the 1987 cDNAs as described above, all GIST samples were placed into one branch, with a Pearson correlation >0.84. The Pearson correlation increased to >0.91, as illustrated by the dendrogram in Fig. 3
, when we applied a hierarchical clustering analysis using the subset of 113 cDNAs with
0.0001. The extremely high correlation between different tumor samples contrasts with that observed in the more common epithelial cancers (22, 23, 24)
. This observation is consistent with a model for the pathogenesis of GIST based on the expansion of an ICC clone with an activating mutation in KIT (4)
, but without the extreme genetic instability commonly seen in epithelial cancers.
A recent report showed a remarkable effect of the tyrosine kinase inhibitor STI571 in a patient with GIST and multiple intra-abdominal, mesenteric, and liver tumors (7) . This drug was recently approved for the treatment of CML, where it acts through inhibition of the BCR-ABL tyrosine kinase characteristic of CML (5 , 6) . GIST is defined by its KIT protein overexpression, which frequently is accompanied by activating mutations (1) . The reported effectiveness of STI571 also in a case with advanced (mutation-positive) GIST (7) suggests that the uncontrolled cell growth in GIST is primarily driven by its KIT overexpression. Like chronic phase CML, GIST may represent clonal expansion of a progenitor cell that has acquired an activating kinase mutation and relatively few additional genetic changes. The great similarity in gene expression pattern among our GIST samples is consistent with this concept. Previous reports have shown that GISTs frequently can acquire specific secondary genetic changes, especially loss of chromosomes 14q and 22q (25, 26, 27) . The effects of these changes on gene expression and clinical behavior have not been fully elucidated, and further studies are needed to address these questions. Because our sample set primarily included large tumors with an aggressive clinical behavior, it is possible that very small tumors or benign GISTs differ in their gene expression patterns. Nonetheless, our data suggest that mutation-positive GISTs display a uniform expression profile consistent with a relatively simple pattern of genetic alterations. These observations lead us to believe that STI571 may be active in a high proportion of KIT mutation-positive GISTs. Our gene expression data are also consistent with the clinical behavior of GIST, which is almost invariably confined to the abdomen without distant metastases (1) , and may bode well for a high rate of response to STI571.
| ACKNOWLEDGMENTS |
|---|
| FOOTNOTES |
|---|
1 S. V. A. was partly supported by a fellowship grant from the Swedish Medical Research Council, M. R. was supported by a postdoctoral fellowship from the Swedish Research Council, and N. N. was supported in part by the Finnish Cultural Foundation. ![]()
2 To whom requests for reprints should be addressed, at National Human Genome Research Institute, NIH, 49 Convent Drive, Bethesda, MD 20892. Phone: (301) 594-5283; Fax: (301) 402-3281; E-mail: pmeltzer{at}nhgri.nih.gov ![]()
3 The abbreviations used are: GIST, gastrointestinal stromal tumor; ICC, interstitial cells of Cajal; CML, chronic myeloid leukemia; IHC, immunohistochemistry; MDS, multidimensional scaling. ![]()
4 http://www.ncbi.nlm.nih.gov/UniGene/build.html. ![]()
5 http://www.nhgri.nih.gov/DIR/microarray. ![]()
Received 8/13/01. Accepted 10/30/01.
| REFERENCES |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
U. Yamaguchi, R. Nakayama, K. Honda, H. Ichikawa, T. Hasegawa, M. Shitashige, M. Ono, A. Shoji, T. Sakuma, H. Kuwabara, et al. Distinct Gene Expression-Defined Classes of Gastrointestinal Stromal Tumor J. Clin. Oncol., September 1, 2008; 26(25): 4100 - 4108. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Vogt, A. Zernecke, M. Beckner, N. Krott, A.-K. Bosserhoff, R. Hoffmann, M. A.M.J. Zandvoort, T. Jahnke, M. Kelm, C. Weber, et al. Blockade of Angio-Associated Migratory Cell Protein Inhibits Smooth Muscle Cell Migration and Neointima Formation in Accelerated Atherosclerosis J. Am. Coll. Cardiol., July 22, 2008; 52(4): 302 - 311. [Abstract] [Full Text] [PDF] |
||||
![]() |
H E Lee, M A Kim, H S Lee, B L Lee, and W H Kim Characteristics of KIT-negative gastrointestinal stromal tumours and diagnostic utility of protein kinase C theta immunostaining J. Clin. Pathol., June 1, 2008; 61(6): 722 - 729. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Hase, T. Yokomizo, T. Shimizu, and M. Nakamura Characterization of an Orphan G Protein-coupled Receptor, GPR20, That Constitutively Activates Gi Proteins J. Biol. Chem., May 9, 2008; 283(19): 12747 - 12755. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Thouennon, A. G. Elkahloun, J. Guillemot, A.-P. Gimenez-Roqueplo, J. Bertherat, A. Pierre, H. Ghzili, L. Grumolato, M. Muresan, M. Klein, et al. Identification of Potential Gene Markers and Insights into the Pathophysiology of Pheochromocytoma Malignancy J. Clin. Endocrinol. Metab., December 1, 2007; 92(12): 4865 - 4872. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Bozulic, P. J. Morin, T. Hunter, and B. A. Hemmings Meeting Report: Targeting the Kinome--20 Years of Tyrosine Kinase Inhibitor Research in Basel Sci. Signal., February 20, 2007; 2007(374): pe8 - pe8. [Abstract] [Full Text] [PDF] |
||||
![]() |
L Tornillo and L M Terracciano An update on molecular genetics of gastrointestinal stromal tumours. J. Clin. Pathol., June 1, 2006; 59(6): 557 - 563. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Baird, S. Davis, C. R. Antonescu, U. L. Harper, R. L. Walker, Y. Chen, A. A. Glatfelter, P. H. Duray, and P. S. Meltzer Gene Expression Profiling of Human Sarcomas: Insights into Sarcoma Biology Cancer Res., October 15, 2005; 65(20): 9226 - 9235. [Abstract] [Full Text] [PDF] |
||||
![]() |
G Eisenhofer, T-T Huynh, K Pacak, F M Brouwers, M M Walther, W M Linehan, P J Munson, M Mannelli, D S Goldstein, and A G Elkahloun Distinct gene expression profiles in norepinephrine- and epinephrine-producing hereditary and sporadic pheochromocytomas: activation of hypoxia-driven angiogenic pathways in von Hippel-Lindau syndrome Endocr. Relat. Cancer, December 1, 2004; 11(4): 897 - 911. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. L. Corless, J. A. Fletcher, and M. C. Heinrich Biology of Gastrointestinal Stromal Tumors J. Clin. Oncol., September 15, 2004; 22(18): 3813 - 3825. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. L. Chen, J. C. Trent, E. F. Wu, G. N. Fuller, L. Ramdas, W. Zhang, A. K. Raymond, V. G. Prieto, C. O. Oyedeji, K. K. Hunt, et al. A Missense Mutation in KIT Kinase Domain 1 Correlates with Imatinib Resistance in Gastrointestinal Stromal Tumors Cancer Res., September 1, 2004; 64(17): 5913 - 5919. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Duensing, N. E. Joseph, F. Medeiros, F. Smith, J. L. Hornick, M. C. Heinrich, C. L. Corless, G. D. Demetri, C. D. M. Fletcher, and J. A. Fletcher Protein Kinase C {theta} (PKC{theta}) Expression and Constitutive Activation in Gastrointestinal Stromal Tumors (GISTs) Cancer Res., August 1, 2004; 64(15): 5127 - 5131. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. All-Ericsson, L. Girnita, A. Muller-Brunotte, B. Brodin, S. Seregard, A. Ostman, and O. Larsson c-Kit-Dependent Growth of Uveal Melanoma Cells: A Potential Therapeutic Target? Invest. Ophthalmol. Vis. Sci., July 1, 2004; 45(7): 2075 - 2082. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. B. West, C. L. Corless, X. Chen, B. P. Rubin, S. Subramanian, K. Montgomery, S. Zhu, C. A. Ball, T. O. Nielsen, R. Patel, et al. The Novel Marker, DOG1, Is Expressed Ubiquitously in Gastrointestinal Stromal Tumors Irrespective of KIT or PDGFRA Mutation Status Am. J. Pathol., July 1, 2004; 165(1): 107 - 113. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Strobel, M. Hartmann, A. Jakob, K. Mikesch, I. Brink, S. Dirnhofer, and A. Marx Thymic Carcinoma with Overexpression of Mutated KIT and the Response to Imatinib N. Engl. J. Med., June 17, 2004; 350(25): 2625 - 2626. [Full Text] [PDF] |
||||
![]() |
P. Blay, A. Astudillo, J. M. Buesa, E. Campo, M. Abad, J. Garcia-Garcia, R. Miquel, V. Marco, M. Sierra, R. Losa, et al. Protein Kinase C {theta} Is Highly Expressed in Gastrointestinal Stromal Tumors But Not in Other Mesenchymal Neoplasias Clin. Cancer Res., June 15, 2004; 10(12): 4089 - 4095. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. K. Lee, A. K. Hsu, J. Sajdak, J. Qin, and P. Pavlidis Coexpression Analysis of Human Genes Across Many Microarray Data Sets Genome Res., June 1, 2004; 14(6): 1085 - 1094. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Simon, S. Panussis, R. Maurer, H. Spichtin, K. Glatz, C. Tapia, M. Mirlacher, A. Rufle, J. Torhorst, and G. Sauter KIT (CD117)-Positive Breast Cancers Are Infrequent and Lack KIT Gene Mutations Clin. Cancer Res., January 1, 2004; 10(1): 178 - 183. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. L. Sawyers Opportunities and challenges in the development of kinase inhibitor therapy for cancer Genes & Dev., December 15, 2003; 17(24): 2998 - 3010. [Full Text] [PDF] |
||||
![]() |
S. C. Linn, R. B. West, J. R. Pollack, S. Zhu, T. Hernandez-Boussard, T. O. Nielsen, B. P. Rubin, R. Patel, J. R. Goldblum, D. Siegmund, et al. Gene Expression Patterns and Gene Copy Number Changes in Dermatofibrosarcoma Protuberans Am. J. Pathol., December 1, 2003; 163(6): 2383 - 2395. [Abstract] [Full Text] |
||||
![]() |
A. Frolov, S. Chahwan, M. Ochs, J. P. Arnoletti, Z.-Z. Pan, O. Favorova, J. Fletcher, M. von Mehren, B. Eisenberg, and A. K. Godwin Response Markers and the Molecular Mechanisms of Action of Gleevec in Gastrointestinal Stromal Tumors Mol. Cancer Ther., August 1, 2003; 2(8): 699 - 709. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. H. Segal, P. Pavlidis, C. R. Antonescu, R. G. Maki, W. S. Noble, D. DeSantis, J. M. Woodruff, J. J. Lewis, M. F. Brennan, A. N. Houghton, et al. Classification and Subtype Prediction of Adult Soft Tissue Sarcoma by Functional Genomics Am. J. Pathol., August 1, 2003; 163(2): 691 - 700. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Komdeur, H. J. Hoekstra, W. M. Molenaar, E. van den Berg, N. Zwart, E. Pras, I. Plaza-Menacho, R. M. W. Hofstra, and W. T. A. van der Graaf Clinicopathologic Assessment of Postradiation Sarcomas: KIT as a Potential Treatment Target Clin. Cancer Res., August 1, 2003; 9(8): 2926 - 2932. [Abstract] [Full Text] [PDF] |
||||
![]() |
U. R. Kees, J. Ford, M. Watson, A. Murch, M. Ringner, R. L. Walker, and P. Meltzer Gene Expression Profiles in a Panel of Childhood Leukemia Cell Lines Mirror Critical Features of the Disease Mol. Cancer Ther., July 1, 2003; 2(7): 671 - 677. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Grumolato, A. G. Elkahloun, H. Ghzili, D. Alexandre, C. Coulouarn, L. Yon, J.-P. Salier, L. E. Eiden, A. Fournier, H. Vaudry, et al. Microarray and Suppression Subtractive Hybridization Analyses of Gene Expression in Pheochromocytoma Cells Reveal Pleiotropic Effects of Pituitary Adenylate Cyclase-Activating Polypeptide on Cell Proliferation, Survival, and Adhesion Endocrinology, June 1, 2003; 144(6): 2368 - 2379. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. C. Borden, L. H. Baker, R. S. Bell, V. Bramwell, G. D. Demetri, B. L. Eisenberg, C. D. M. Fletcher, J. A. Fletcher, M. Ladanyi, P. Meltzer, et al. Soft Tissue Sarcomas of Adults: State of the Translational Science Clin. Cancer Res., June 1, 2003; 9(6): 1941 - 1956. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Hedenfalk, M. Ringner, A. Ben-Dor, Z. Yakhini, Y. Chen, G. Chebil, R. Ach, N. Loman, H. Olsson, P. Meltzer, et al. Molecular classification of familial non-BRCA1/BRCA2 breast cancer PNAS, March 4, 2003; 100(5): 2532 - 2537. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Sjogren, J. M. Meis-Kindblom, C. Orndal, P. Bergh, K. Ptaszynski, P. Aman, L.-G. Kindblom, and G. Stenman Studies on the Molecular Pathogenesis of Extraskeletal Myxoid Chondrosarcoma--Cytogenetic, Molecular Genetic, and cDNA Microarray Analyses Am. J. Pathol., March 1, 2003; 162(3): 781 - 792. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Adeyinka, E. Emberley, Y. Niu, L. Snell, L. C. Murphy, H. Sowter, C. C. Wykoff, A. L. Harris, and P. H. Watson Analysis of Gene Expression in Ductal Carcinoma in Situ of the Breast Clin. Cancer Res., December 1, 2002; 8(12): 3788 - 3795. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. van de Rijn and B. P. Rubin Gene Expression Studies on Soft Tissue Tumors Am. J. Pathol., November 1, 2002; 161(5): 1531 - 1534. [Full Text] [PDF] |
||||
![]() |
A. V. Moses, M. A. Jarvis, C. Raggo, Y. C. Bell, R. Ruhl, B. G. M. Luukkonen, D. J. Griffith, C. L. Wait, B. J. Druker, M. C. Heinrich, et al. Kaposi's Sarcoma-Associated Herpesvirus-Induced Upregulation of the c-kit Proto-Oncogene, as Identified by Gene Expression Profiling, Is Essential for the Transformation of Endothelial Cells J. Virol., July 17, 2002; 76(16): 8383 - 8399. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||