Experimental treatment of transfusion dependent 5q- syndrome with leucovorin

Candido E Rivera, Lisa A. Krueger

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The 5q- syndrome is a myelodysplastic disorder characterized by refractory macrocytic anemia with dyserythropoiesis, low or low normal WBC counts, hypolobulated megakaryocytes with normal to high platelet counts, and acquired deletion of part of the long arm of chromosome 5 usually as the sole marrow karyotypic abnormality. The majority of patients are female; the median age is 65 years. The three most common deletions are del(5)(q!3q33), del(5)(q!4q33) and del(5)(q!5q33); however, all bands between 5qll.2 and 5q35 have been implicated as breakpoints. The dihydrofolate reductase (DHFR) gene has been mapped to band 5ql 3. We hypothesized that one copy of the DHFR gene may be deleted in some 5q- patients, leaving only an abnormal DHFR allele and causing cytopenias that could potentially be normalized by leucovorin. To test this hypothesis, N1H protocol 98-CC-0101 was designed to study up to 14 patients with transfusion dependent 5qsyndrome. To date, six patients have been enrolled. Patients were treated with 25 mg of leucovorin orally daily for three months. Bone marrow samples were obtained from all patients prior to therapy, and from five of the six patients after treatment. Pretreatment karyotypes were: 46,XX,del(5)(ql5q35.1)[20], 46,XX,del(5)(q13q33)[27]/47,XX,+8[3], 46.XX,del(5)(q13q33)[5]/46,XX[15], 46,XX,del(5)(ql5q35)[3]/46,XX[3], 46.XY,del(5)(q31q35)[8]/46,XY[13], 46,XX,del(5)(q22q33)[10]/46,XX[10]. Metaphase FISH analysis was performed on bone marrow from patients 2-6 using a reporter probe to 5pl5.2 (D5S23, VYSIS) and a BAC clone, 325J23, for DHFR (gift from Dr. Larry Mesner, PNAS 97(141:7921-6) that we mapped to 5q13.3. DHFR was retained on both the normal and deleted chromosomes 5 in all cases. All patients had a normal sequence of the DHFR gene amplified from bone marrow RNA. Colony assays showed markedly decreased CFUE and moderately decreased CFU-G and CFU-M as compared with controls, with and without leucovorin supplementation of the bone marrow culture media. All patients remained transfusion dependent after 3 months' treatment with leucovorin, with no significant increase in their reticulocyte counts, and no significant change in their marrow morphology or cytogenetics. Although eight additional patients are needed to confirm the preliminary results, these data suggest the DHFR gene does not play a role in the etiology of the 5q- syndrome, and leucovorin does not reverse the refractory anemia of patients with this disorder.

Original languageEnglish (US)
JournalBlood
Volume96
Issue number11 PART II
StatePublished - 2000
Externally publishedYes

Fingerprint

Tetrahydrofolate Dehydrogenase
Leucovorin
Bone
Genes
Bone Marrow
Chromosomes
Refractory materials
Therapeutics
Refractory Anemia
Chromosomes, Human, Pair 5
Platelets
Chromosome 5q Deletion Syndrome
Culture Media
Macrocytic Anemia
Assays
Reticulocyte Count
Gift Giving
RNA
Megakaryocytes
Metaphase

ASJC Scopus subject areas

  • Hematology

Cite this

Experimental treatment of transfusion dependent 5q- syndrome with leucovorin. / Rivera, Candido E; Krueger, Lisa A.

In: Blood, Vol. 96, No. 11 PART II, 2000.

Research output: Contribution to journalArticle

@article{bef74c58e9384e4ab36687af85730846,
title = "Experimental treatment of transfusion dependent 5q- syndrome with leucovorin",
abstract = "The 5q- syndrome is a myelodysplastic disorder characterized by refractory macrocytic anemia with dyserythropoiesis, low or low normal WBC counts, hypolobulated megakaryocytes with normal to high platelet counts, and acquired deletion of part of the long arm of chromosome 5 usually as the sole marrow karyotypic abnormality. The majority of patients are female; the median age is 65 years. The three most common deletions are del(5)(q!3q33), del(5)(q!4q33) and del(5)(q!5q33); however, all bands between 5qll.2 and 5q35 have been implicated as breakpoints. The dihydrofolate reductase (DHFR) gene has been mapped to band 5ql 3. We hypothesized that one copy of the DHFR gene may be deleted in some 5q- patients, leaving only an abnormal DHFR allele and causing cytopenias that could potentially be normalized by leucovorin. To test this hypothesis, N1H protocol 98-CC-0101 was designed to study up to 14 patients with transfusion dependent 5qsyndrome. To date, six patients have been enrolled. Patients were treated with 25 mg of leucovorin orally daily for three months. Bone marrow samples were obtained from all patients prior to therapy, and from five of the six patients after treatment. Pretreatment karyotypes were: 46,XX,del(5)(ql5q35.1)[20], 46,XX,del(5)(q13q33)[27]/47,XX,+8[3], 46.XX,del(5)(q13q33)[5]/46,XX[15], 46,XX,del(5)(ql5q35)[3]/46,XX[3], 46.XY,del(5)(q31q35)[8]/46,XY[13], 46,XX,del(5)(q22q33)[10]/46,XX[10]. Metaphase FISH analysis was performed on bone marrow from patients 2-6 using a reporter probe to 5pl5.2 (D5S23, VYSIS) and a BAC clone, 325J23, for DHFR (gift from Dr. Larry Mesner, PNAS 97(141:7921-6) that we mapped to 5q13.3. DHFR was retained on both the normal and deleted chromosomes 5 in all cases. All patients had a normal sequence of the DHFR gene amplified from bone marrow RNA. Colony assays showed markedly decreased CFUE and moderately decreased CFU-G and CFU-M as compared with controls, with and without leucovorin supplementation of the bone marrow culture media. All patients remained transfusion dependent after 3 months' treatment with leucovorin, with no significant increase in their reticulocyte counts, and no significant change in their marrow morphology or cytogenetics. Although eight additional patients are needed to confirm the preliminary results, these data suggest the DHFR gene does not play a role in the etiology of the 5q- syndrome, and leucovorin does not reverse the refractory anemia of patients with this disorder.",
author = "Rivera, {Candido E} and Krueger, {Lisa A.}",
year = "2000",
language = "English (US)",
volume = "96",
journal = "Blood",
issn = "0006-4971",
publisher = "American Society of Hematology",
number = "11 PART II",

}

TY - JOUR

T1 - Experimental treatment of transfusion dependent 5q- syndrome with leucovorin

AU - Rivera, Candido E

AU - Krueger, Lisa A.

PY - 2000

Y1 - 2000

N2 - The 5q- syndrome is a myelodysplastic disorder characterized by refractory macrocytic anemia with dyserythropoiesis, low or low normal WBC counts, hypolobulated megakaryocytes with normal to high platelet counts, and acquired deletion of part of the long arm of chromosome 5 usually as the sole marrow karyotypic abnormality. The majority of patients are female; the median age is 65 years. The three most common deletions are del(5)(q!3q33), del(5)(q!4q33) and del(5)(q!5q33); however, all bands between 5qll.2 and 5q35 have been implicated as breakpoints. The dihydrofolate reductase (DHFR) gene has been mapped to band 5ql 3. We hypothesized that one copy of the DHFR gene may be deleted in some 5q- patients, leaving only an abnormal DHFR allele and causing cytopenias that could potentially be normalized by leucovorin. To test this hypothesis, N1H protocol 98-CC-0101 was designed to study up to 14 patients with transfusion dependent 5qsyndrome. To date, six patients have been enrolled. Patients were treated with 25 mg of leucovorin orally daily for three months. Bone marrow samples were obtained from all patients prior to therapy, and from five of the six patients after treatment. Pretreatment karyotypes were: 46,XX,del(5)(ql5q35.1)[20], 46,XX,del(5)(q13q33)[27]/47,XX,+8[3], 46.XX,del(5)(q13q33)[5]/46,XX[15], 46,XX,del(5)(ql5q35)[3]/46,XX[3], 46.XY,del(5)(q31q35)[8]/46,XY[13], 46,XX,del(5)(q22q33)[10]/46,XX[10]. Metaphase FISH analysis was performed on bone marrow from patients 2-6 using a reporter probe to 5pl5.2 (D5S23, VYSIS) and a BAC clone, 325J23, for DHFR (gift from Dr. Larry Mesner, PNAS 97(141:7921-6) that we mapped to 5q13.3. DHFR was retained on both the normal and deleted chromosomes 5 in all cases. All patients had a normal sequence of the DHFR gene amplified from bone marrow RNA. Colony assays showed markedly decreased CFUE and moderately decreased CFU-G and CFU-M as compared with controls, with and without leucovorin supplementation of the bone marrow culture media. All patients remained transfusion dependent after 3 months' treatment with leucovorin, with no significant increase in their reticulocyte counts, and no significant change in their marrow morphology or cytogenetics. Although eight additional patients are needed to confirm the preliminary results, these data suggest the DHFR gene does not play a role in the etiology of the 5q- syndrome, and leucovorin does not reverse the refractory anemia of patients with this disorder.

AB - The 5q- syndrome is a myelodysplastic disorder characterized by refractory macrocytic anemia with dyserythropoiesis, low or low normal WBC counts, hypolobulated megakaryocytes with normal to high platelet counts, and acquired deletion of part of the long arm of chromosome 5 usually as the sole marrow karyotypic abnormality. The majority of patients are female; the median age is 65 years. The three most common deletions are del(5)(q!3q33), del(5)(q!4q33) and del(5)(q!5q33); however, all bands between 5qll.2 and 5q35 have been implicated as breakpoints. The dihydrofolate reductase (DHFR) gene has been mapped to band 5ql 3. We hypothesized that one copy of the DHFR gene may be deleted in some 5q- patients, leaving only an abnormal DHFR allele and causing cytopenias that could potentially be normalized by leucovorin. To test this hypothesis, N1H protocol 98-CC-0101 was designed to study up to 14 patients with transfusion dependent 5qsyndrome. To date, six patients have been enrolled. Patients were treated with 25 mg of leucovorin orally daily for three months. Bone marrow samples were obtained from all patients prior to therapy, and from five of the six patients after treatment. Pretreatment karyotypes were: 46,XX,del(5)(ql5q35.1)[20], 46,XX,del(5)(q13q33)[27]/47,XX,+8[3], 46.XX,del(5)(q13q33)[5]/46,XX[15], 46,XX,del(5)(ql5q35)[3]/46,XX[3], 46.XY,del(5)(q31q35)[8]/46,XY[13], 46,XX,del(5)(q22q33)[10]/46,XX[10]. Metaphase FISH analysis was performed on bone marrow from patients 2-6 using a reporter probe to 5pl5.2 (D5S23, VYSIS) and a BAC clone, 325J23, for DHFR (gift from Dr. Larry Mesner, PNAS 97(141:7921-6) that we mapped to 5q13.3. DHFR was retained on both the normal and deleted chromosomes 5 in all cases. All patients had a normal sequence of the DHFR gene amplified from bone marrow RNA. Colony assays showed markedly decreased CFUE and moderately decreased CFU-G and CFU-M as compared with controls, with and without leucovorin supplementation of the bone marrow culture media. All patients remained transfusion dependent after 3 months' treatment with leucovorin, with no significant increase in their reticulocyte counts, and no significant change in their marrow morphology or cytogenetics. Although eight additional patients are needed to confirm the preliminary results, these data suggest the DHFR gene does not play a role in the etiology of the 5q- syndrome, and leucovorin does not reverse the refractory anemia of patients with this disorder.

UR - http://www.scopus.com/inward/record.url?scp=26344474284&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=26344474284&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:26344474284

VL - 96

JO - Blood

JF - Blood

SN - 0006-4971

IS - 11 PART II

ER -