Clinical Cancer Research, Vol 4, Issue 9 2169-2177, Copyright © 1998 by American Association for Cancer Research

ARTICLES

Reduced folate carrier gene expression in childhood acute lymphoblastic leukemia: relationship to immunophenotype and ploidy

L Zhang, JW Taub, M Williamson, SC Wong, B Hukku, J Pullen, Y Ravindranath and LH Matherly
Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, MI 48201, USA.

Reduced folate carrier (RFC) transcripts in human leukemias were measured by a competitive PCR assay. Total RNAs were reverse transcribed and amplified in the presence of competitive templates for RFC and beta-actin. RFC transcripts were normalized to transcripts for beta-actin. In a series of K562 sublines, a approximately 30-fold range of RFC transcripts measured by PCR assay closely agreed with results of Northern analysis and varied in proportion to RFC protein on Western blots and [3H]methotrexate transport. RFC transcripts varied over a 88-fold range in 49 specimens from 48 children with acute lymphoblastic leukemia (ALL). Median RFC transcripts were similar for 15 T-cell and 33 B-precursor ALL samples (RFC/beta-actin = 6.13 x 10(-3) and 7.92 x 10(-3), respectively) and for 41 diagnostic (7.20 x 10(-3)) and 8 relapse (5.58 x 10(-3)) samples. Whereas PCR measurements of RFC transcripts approximated changes in methotrexate transport in B-precursor ALL blasts (n = 10), for T-ALL blasts (n = 12) there was no apparent relationship between these parameters. For hyperdiploid B-precursor blasts (n = 11) with greater than 52 chromosomes and three to five copies of chromosome 21, the median RFC transcript level was approximately 3-fold higher than that for diploid B-precursor blasts. RFC transcripts were also elevated for two of three B-precursor specimens with acquired trisomy 21. Our results suggest that RFC gene expression is far more predictive of methotrexate uptake capacity in B-precursor than T-ALL and that increased copies of chromosome 21 in B-precursor ALL blasts are generally associated with increased RFC transcripts. Hence, the good prognosis for children with hyperdiploid B-precursor ALL treated with antimetabolite-based chemotherapy and the high levels of methotrexate and methotrexate polyglutamates accumulated may, in part, reflect elevated RFC gene expression and capacities for methotrexate transport.

This article has been cited by other articles:

				Y. Ge, C. L. Haska, K. LaFiura, M. Devidas, S. B. Linda, M. Liu, R. Thomas, J. W. Taub, and L. H. Matherly Prognostic Role of the Reduced Folate Carrier, the Major Membrane Transporter for Methotrexate, in Childhood Acute Lymphoblastic Leukemia: A Report from the Children's Oncology Group Clin. Cancer Res., January 15, 2007; 13(2): 451 - 457. [Abstract] [Full Text] [PDF]

				M. Liu, Y. Ge, S. G. Payton, A. Aboukameel, S. Buck, R. M. Flatley, C. Haska, R. Mohammad, J. W. Taub, and L. H. Matherly Transcriptional Regulation of the Human Reduced Folate Carrier in Childhood Acute Lymphoblastic Leukemia Cells Clin. Cancer Res., January 15, 2006; 12(2): 608 - 616. [Abstract] [Full Text] [PDF]

				J Wolf, T Stranzl, M Filipits, G Pohl, R Pirker, B Leeb, and J S Smolen Expression of resistance markers to methotrexate predicts clinical improvement in patients with rheumatoid arthritis Ann Rheum Dis, April 1, 2005; 64(4): 564 - 568. [Abstract] [Full Text] [PDF]

				K. Fotoohi, G. Jansen, Y. G. Assaraf, L. Rothem, M. Stark, I. Kathmann, J. Gregorczyk, G. J. Peters, and F. Albertioni Disparate mechanisms of antifolate resistance provoked by methotrexate and its metabolite 7-hydroxymethotrexate in leukemia cells: implications for efficacy of methotrexate therapy Blood, December 15, 2004; 104(13): 4194 - 4201. [Abstract] [Full Text] [PDF]

				R. M. Flatley, S. G. Payton, J. W. Taub, and L. H. Matherly Primary Acute Lymphoblastic Leukemia Cells Use a Novel Promoter and 5'Noncoding Exon for the Human Reduced Folate Carrier That Encodes a Modified Carrier Translated from an Upstream Translational Start Clin. Cancer Res., August 1, 2004; 10(15): 5111 - 5122. [Abstract] [Full Text] [PDF]

				C. Laverdiere, S. Chiasson, I. Costea, A. Moghrabi, and M. Krajinovic Polymorphism G80A in the reduced folate carrier gene and its relationship to methotrexate plasma levels and outcome of childhood acute lymphoblastic leukemia Blood, November 15, 2002; 100(10): 3832 - 3834. [Abstract] [Full Text] [PDF]

				J. R. Whetstine, T. L. Witt, and L. H. Matherly The Human Reduced Folate Carrier Gene Is Regulated by the AP2 and Sp1 Transcription Factor Families and a Functional 61-Base Pair Polymorphism J. Biol. Chem., November 8, 2002; 277(46): 43873 - 43880. [Abstract] [Full Text] [PDF]

				I. D. Goldman Membrane Transport of Chemotherapeutics and Drug Resistance: Beyond the ABC Family of Exporters to the Role of Carrier-mediated Processes Clin. Cancer Res., January 1, 2002; 8(1): 4 - 6. [Full Text] [PDF]

				C. M. Zwaan, G. J. L. Kaspers, R. Pieters, K. Hahlen, G. E. Janka-Schaub, C. H. van Zantwijk, D. R. Huismans, E. de Vries, M. G. Rots, G. J. Peters, et al. Different drug sensitivity profiles of acute myeloid and lymphoblastic leukemia and normal peripheral blood mononuclear cells in children with and without Down syndrome Blood, January 1, 2002; 99(1): 245 - 251. [Abstract] [Full Text] [PDF]

				J. R. Whetstine, A. J. Gifford, T. Witt, X. Y. Liu, R. M. Flatley, M. Norris, M. Haber, J. W. Taub, Y. Ravindranath, and L. H. Matherly Single Nucleotide Polymorphisms in the Human Reduced Folate Carrier: Characterization of a High-Frequency G/A Variant at Position 80 and Transport Properties of the His27 and Arg27 Carriers Clin. Cancer Res., November 1, 2001; 7(11): 3416 - 3422. [Abstract] [Full Text] [PDF]

				J. L. Wiemels, R. N. Smith, G. M. Taylor, O. B. Eden, F. E. Alexander, M. F. Greaves, and U. K. C. C. S. Investigators Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and risk of molecularly defined subtypes of childhood acute leukemia PNAS, March 7, 2001; (2001) 61408298. [Abstract] [Full Text]

				J. W. Taub, X. Huang, Y. Ge, J. A. Dutcher, M. L. Stout, R. M. Mohammad, Y. Ravindranath, and L. H. Matherly Cystathionine-{beta}-Synthase cDNA Transfection Alters the Sensitivity and Metabolism of 1-{beta}-D-Arabinofuranosylcytosine in CCRF-CEM Leukemia Cells in Vitro and in Vivo: A Model of Leukemia in Down Syndrome Cancer Res., November 1, 2000; 60(22): 6421 - 6426. [Abstract] [Full Text]

				N. A. Heerema, H. N. Sather, M. G. Sensel, T. Zhang, R. J. Hutchinson, J. B. Nachman, B. J. Lange, P. G. Steinherz, B. C. Bostrom, G. H. Reaman, et al. Prognostic Impact of Trisomies of Chromosomes 10, 17, and 5 Among Children With Acute Lymphoblastic Leukemia and High Hyperdiploidy (> 50 Chromosomes) J. Clin. Oncol., May 9, 2000; 18(9): 1876 - 1887. [Abstract] [Full Text] [PDF]

				J. W. Taub, X. Huang, L. H. Matherly, M. L. Stout, S. A. Buck, G. V. Massey, D. L. Becton, M. N. Chang, H. J. Weinstein, and Y. Ravindranath Expression of Chromosome 21-Localized Genes in Acute Myeloid Leukemia: Differences Between Down Syndrome and Non-Down Syndrome Blast Cells and Relationship to In Vitro Sensitivity to Cytosine Arabinoside and Daunorubicin Blood, August 15, 1999; 94(4): 1393 - 1400. [Abstract] [Full Text] [PDF]

				R. Zhao, I. G. Sharina, and I. D. Goldman Pattern of Mutations that Results in Loss of Reduced Folate Carrier Function under Antifolate Selective Pressure Augmented by Chemical Mutagenesis Mol. Pharmacol., July 1, 1999; 56(1): 68 - 76. [Abstract] [Full Text]

				J. R. Whetstine and L. H. Matherly The Basal Promoters for the Human Reduced Folate Carrier Gene Are Regulated by a GC-box and a cAMP-response Element/AP-1-like Element. BASIS FOR TISSUE-SPECIFIC GENE EXPRESSION J. Biol. Chem., February 23, 2001; 276(9): 6350 - 6358. [Abstract] [Full Text] [PDF]

				J. L. Wiemels, R. N. Smith, G. M. Taylor, O. B. Eden, F. E. Alexander, M. F. Greaves, and United Kingdom Childhood Cancer Study Investigator Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and risk of molecularly defined subtypes of childhood acute leukemia PNAS, March 27, 2001; 98(7): 4004 - 4009. [Abstract] [Full Text] [PDF]