Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report a 65-year-old patient who presented a rapid eruption of keratoses on sun-exposed areas and an explosive transformation into several squamous-cell carcinomas, occurring during the accelerated phase of a chronic granulocytic leukemia. Clinical findings resembled those usually described in xeroderma pigmentosum. The role of immunosuppression, chemotherapy and possible genetic predisposition is discussed.
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PMID:Rapid development of multiple squamous-cell carcinomas during chronic granulocytic leukemia. 176 15

We demonstrated previously that the nucleoside of fludarabine (F-ara-A), a clinically effective agent against chronic lymphocytic leukemia and low-grade lymphoma, produces synergistic cytotoxicity against cisplatin-resistant CP2.0 human colon tumor cells when administered in combination with cisplatin. The purpose of this study was 2-fold: (i) to determine whether the synergy occurs in K562 human chronic myelogenous leukemia cells, which, unlike CP2.0 cells, are relatively resistant to drug-induced apoptosis because they express P210(bcr-abl) and (ii) to study the underlying mechanism for the synergy if the enhancement of cytotoxicity occurs in K562 cells. When K562 cells were treated with fludarabine nucleoside and cisplatin as single agents for 4 hr, IC50 values for fludarabine and cisplatin were 3.33 and 2.28 microM, respectively, as measured by a clonogenic survival assay. The simultaneous treatment of K562 cells with the two agents resulted in synergistic cell killing as determined by median-effect analysis. Such synergistic cell killing by combined cisplatin and fludarabine could not be detected in repair-deficient human xeroderma pigmentosum cell lines. Within the range of cytotoxic concentrations, fludarabine (2.5-15 microM) and cisplatin (3-30 microM) as single agents produced no detectable internucleosomal DNA fragmentation as revealed by gel electrophoresis, nor did the combination of the two drugs induce apoptotic DNA degradation. The effects of fludarabine on the repair of cisplatin-induced DNA adducts and interstrand cross-links in K562 cells were analyzed to determine their correlation with the cytotoxic synergy. The interstrand cross-links were measured by the ethidium bromide binding fluorescence assay and quantitative Southern blotting technique. Repair of the intrastrand adducts was detected with whole-cell extracts using a cisplatin-damaged plasmid as the substrate for the in vitro repair assay. Fludarabine at clinically achievable concentrations (1.5-4.5 microM fludarabine nucleoside; 20-100 microM fludarabine triphosphate) inhibited the repair of the DNA lesions induced by cisplatin in a dose-dependent fashion in K562 cells but not in xeroderma pigmentosum cells. Cotreatment with fludarabine preferentially increased the number of interstrand cross-links induced by cisplatin in actively transcribed genes in K562 cells. These data demonstrate the DNA-repair-inhibitory effect of fludarabine and suggest that this effect may contribute to the synergistic cytotoxicity of the fludarabine/cisplatin combination that resulted in decreased clonogenic survival of apoptosis-resistant K562 cells.
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PMID:Fludarabine-mediated repair inhibition of cisplatin-induced DNA lesions in human chronic myelogenous leukemia-blast crisis K562 cells: induction of synergistic cytotoxicity independent of reversal of apoptosis resistance. 935 70

This paper commemorates the multiple contributions of Dirk Bootsma to human genetics. During a scientific 'Bootsma' cruise on his sailing-boat 'de Losbol', we visit a variety of scenery locations along the lakes and canals in Friesland, passing the highlights of Dirk Bootsma's scientific oeuvre. Departing from 'de Fluessen', his homeport, with his PhD work on the effect of X-rays and UV on cell cycle progression, we head for the pioneering endeavours of his team on mapping genes on human chromosomes by cell hybridization. Next we explore the use of cell hybrids by the Bootsma team culminating in the molecular cloning of one of the first chromosomal breakpoints involved in oncogenesis: the bcr-abl fusion gene responsible for chronic myelocytic leukemia. This seminal achievement enabled later development of new methods for early detection and very promising therapeutic intervention. A series of highlights at the horizon constitute the contributions of his team to the field of DNA repair, beginning with the discovery of genetic heterogeneity in the repair syndrome xeroderma pigmentosum (XP) followed later by the cloning of a large number of human repair genes. This led to the discovery that DNA repair is strongly conserved in evolution rendering knowledge from yeast relevant for mammals and vice versa. In addition, it resolved the molecular basis of several repair syndromes and permitted functional analysis of the encoded proteins. Another milestone is the discovery of the surprising connection between DNA repair and transcription initiation via the dual functional TFIIH complex in collaboration with Jean-Marc Egly et al. in Strasbourg. This provided an explanation for many puzzling clinical features and triggered a novel concept in human genetics: the existence of repair/transcription syndromes. The generation of many mouse mutants carrying defects in repair pathways yielded valuable models for assessing the clinical relevance of DNA repair including carcinogenesis and the identification of a link between DNA damage and premature aging. His team also opened a fascinating area of cell biology with the analysis of repair and transcription in living cells. A final surprising evolutionary twist was the discovery that photolyases designed for the light-dependent repair of UV-induced DNA lesions appeared to be adopted for driving the mammalian biological clock. The latter indicates that it is time to return to 'de Fluessen', where we will consider briefly the merits of Dirk Bootsma for Dutch science in general.
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PMID:From xeroderma pigmentosum to the biological clock contributions of Dirk Bootsma to human genetics. 1134 93

Previous studies have demonstrated that p210 BCR/ABL1 interacts directly with the xeroderma pigmentosum group B (XPB) protein, and that XPB is phosphorylated on tyrosine in cells that express p210 BCR/ABL1. In the current study, we have constructed a p210 BCR/ABL1 mutant that can no longer bind to XPB. The mutant has normal kinase activity and interacts with GRB2, but can no longer phosphorylate XPB. Loss of XPB binding is associated with reduced expression of c-MYC and reduced transforming potential in ex-vivo clonogenicity assays, but does not affect nucleotide excision repair in lymphoid or myeloid cells. When examined in a bone marrow transplantation (BMT) model for chronic myelogenous leukemia, mice that express the mutant exhibit attenuated myeloproliferation and lymphoproliferation when compared with mice that express unmodified p210 BCR/ABL1. Thus, the mutant-transplanted mice show predominantly neutrophilic expansion and altered progenitor expansion, and have significantly extended lifespans. This was confirmed in a BMT model for B-cell acute lymphoblastic leukemia, wherein the majority of the mutant-transplanted mice remain disease free. These results suggest that the interaction between p210 BCR/ABL1 and XPB can contribute to disease progression by influencing the lineage commitment of lymphoid and myeloid progenitors.
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PMID:Loss of the xeroderma pigmentosum group B protein binding site impairs p210 BCR/ABL1 leukemogenic activity. 2395 90

The genetic polymorphisms of X-ray repair cross complementing group 1 (XRCC1), X-ray repair cross complementing group 3 (XRCC3), and xeroderma pigmentosum complementation group D (XPD) repair genes may lead to genetic instability and leukemogenesis. The purpose of the study was to evaluate the association between XRCC1 Arg399Gln, Arg280His and Arg194Trp, XRCC3 Thr241Met, and XPD Lys751Gln polymorphisms and the risk of developing CML in Romanian patients. A total of 156 patients diagnosed with CML and 180 healthy controls were included in this study. We found no association between CML and XRCC1 or XRCC3 variant genotypes in any of the investigated cases. A significant difference was observed in the variant genotype frequencies of the XPD Lys751Gln polymorphism between the patients with CML and control group (for variant homozygous genotypes, OR = 2.37; 95% CI = 1.20-4.67; P value = 0.016 and for combined heterozygous and variant homozygous genotypes, OR = 1.72; 95% CI = 1.10-2.69; P value = 0.019). This was also observed when analyzing the variant 751Gln allele (OR = 1.54; 95% CI = 1.13-2.11; P value = 0.008). Our results suggest that the XPD Lys751Gln variant genotype increases the risk of CML.
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PMID:Polymorphism of XRCC1, XRCC3, and XPD genes and risk of chronic myeloid leukemia. 2495 48