Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fanconi anemia, an autosomal recessive and X-linked disorder, is known to be associated with a variety of neoplasms. Liver tumors are one of the most frequently observed neoplasms but the association between the two disorders remains obscure. We present a case of a 27-year old female Fanconi anemia patient diagnosed with a mass on the right lobe of the liver measuring 90x75x60 mm. Histopathological examination of the mass after right hepatic lobectomy revealed focal nodular hyperplasia. This appears to be the first reported case of a hepatic focal nodular hyperplasia of such proportion associated with Fanconi anemia. Previously reported cases of liver tumors in association with Fanconi anemia in the English Literature were either hepatocellular carcinomas or hepatic adenomas.
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PMID:Hepatic focal nodular hyperplasia developing in a Fanconi anemia patient: a case report and literature review. 1692 23

Fanconi anemia (FA) is a rare autosomal recessive and X-linked chromosomal instability disorder. At least eight FA proteins (FANCA, B, C, E, F, G, L, and M) form a nuclear core complex required for monoubiquitination of a downstream protein, FANCD2. The human FANCF protein reportedly functions as a molecular adaptor within the FA nuclear complex, bridging between the subcomplexes A:G and C:E. Our x-ray crystallographic studies of the C-terminal domain of FANCF reveal a helical repeat structure similar to the Cand1 regulator of the Cul1-Rbx1-Skp1-Fbox(Skp2) ubiquitin ligase complex. Two C-terminal loops of FANCF are essential for monoubiquitination of FANCD2 and normal cellular resistance to the DNA cross-linking agent mitomycin C. FANCF mutants bearing amino acid substitutions in this C-terminal surface fail to interact with other components of the FA complex, indicating that this surface is critical for the proper assembly of the FA core complex.
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PMID:Structural determinants of human FANCF protein that function in the assembly of a DNA damage signaling complex. 1708 80

CD40 ligand (CD40L) deficiency is an X-linked combined immunodeficiency characterized by impaired class switch recombination. We analyzed clinical and molecular findings in 11 Argentinian patients from seven unrelated families. The mean age at onset of symptoms was 1.1 years (0.5-3.0 years) and the 10 alive patients have a median age of 17 years. We identified two nonsense mutations, including R11X reported as a "hypomorphic" defect, four missense mutations, and one point deletion. Although R11X was associated herein with parvovirus B19-anemia and higher Igs levels as previously described, histoplasmosis and Pneumocystis jiroveci pneumonia were also present. Other so-called "milder" mutation, T254M, was present in three related patients clinically and immunologically undistinguishable from the rest of the cohort. Furthermore, 10 of the 11 patients, having heterogeneous mutations, never had persistent neutropenia, none presented Cryptosporidium sp. infection nor developed liver-biliary tract disease, highlighting the debatable concept of "milder" mutations.
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PMID:Clinical follow-up of 11 Argentinian CD40L-deficient patients with 7 unique mutations including the so-called "milder" mutants. 1735 59

Fanconi anemia (FA) is a recessively inherited syndrome with predisposition to bone marrow failure and malignancies. Hypersensitivity to cross-linking agents is a cellular feature used to confirm the diagnosis. The mode of inheritance is autosomal recessive (12 subtypes) as well as X-linked (one subtype). Most genetic subtypes have initially been defined as "complementation groups" by cell fusion studies. Here we report a comprehensive genetic subtyping approach for FA that is primarily based on mutation screening, supplemented by protein expression analysis and by functional assays to test for pathogenicity of unclassified variants. Of 80 FA cases analyzed, 73 (91%) were successfully subtyped. In total, 92 distinct mutations were detected, of which 56 were novel (40 in FANCA, eight in FANCC, two in FANCD1, three in FANCE, one in FANCF, and three in FANCG). All known complementation groups were represented, except D2, J, L, and M. Three patients could not be classified because proliferating cell cultures from the probands were lacking. In cell lines from the remaining four patients, immunoblotting was used to determine their capacity to monoubiquitinate FANCD2. In one case FANCD2 monoubiquitination was normal, indicating a defect downstream. In the remaining three cases monoubiquitination was not detectable, indicating a defect upstream. In the latter four patients, pathogenic mutations in a known FA gene may have been missed, or these patients might represent novel genetic subtypes. We conclude that direct mutation screening allows a molecular diagnosis of FA in the vast majority of patients, even in cases where growing cells from affected individuals are unavailable. Proliferating cell lines are required in a minority (<15%) of the patients, to allow testing for FANCD2 ubiquitination status and sequencing of FANCD2 using cDNA, to avoid interference from pseudogenes.
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PMID:Genetic subtyping of Fanconi anemia by comprehensive mutation screening. 1792 55

Homozygous loss of activity at the breast cancerpredisposing genes BRCA1 and BRCA2 (FANCD1) confers increased susceptibility to DNA double strand breaks, but this genotype occurs only in the tumor itself, following loss of heterozygosity at one of these loci. Thus, if these genes play a role in tumor etiology as opposed to tumor progression, they must manifest a heterozygous phenotype at the cellular level. To investigate the potential consequences of somatic heterozygosity for a BRCA1 mutation demonstrably associated with breast carcinogenesis on background somatic mutational burden, we applied the two standard assays of in vivo human somatic mutation to blood samples from a manifesting carrier of the Q1200X mutation in BRCA1 whose tumor was uniquely ascertained through an MRI screening study. The patient had an allele-loss mutation frequency of 19.4 x 10(-6) at the autosomal GPA locus in erythrocytes and 17.1 x 10(-6) at the X-linked HPRT locus in lymphocytes. Both of these mutation frequencies are significantly higher than expected from age-matched disease-free controls (P < 0.05). Mutation at the HPRT locus was similarly elevated in lymphoblastoid cell lines established from three other BRCA1 mutation carriers with breast cancer. Our patient's GPA mutation frequency is below the level established for diagnosis of homozygous Fanconi anemia patients, but consistent with data from obligate heterozygotes. The increased HPRT mutation frequency is more reminiscent of data from patients with xeroderma pigmentosum, a disease characterized by UV sensitivity and deficiency in the nucleotide excision pathway of DNA repair. Therefore, this BRCA1-associated breast cancer patient manifests a unique phenotype of increased background mutagenesis that likely contributed to the development of her disease independent of loss of heterozygosity at the susceptibility locus.
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PMID:Elevated levels of somatic mutation in a manifesting BRCA1 mutation carrier. 1815 61

Type 1 diabetes (T1D) is associated with autoimmune thyroid disease (AIT), celiac disease (CD), Addison's disease (AD), and other autoimmune diseases. These diseases can occur simultaneously in defined syndromes with distinct pathophysiology and characteristics: autoimmune polyendocrine syndromes (APSs) and the immunodysregulation polyendocrinopathy enteropathy X-linked syndrome (IPEX). APSs were initially defined as a multiple endocrine gland insufficiency associated to an autoimmune disease in a patient. APS-1 is characterized by the evidence of chronic candidiasis, chronic hypoparathyroidism, AD and T1D could be present as part of this syndrome. The combination of autoimmune adrenal insufficiency with AIT and/or type 1 autoimmune diabetes mellitus defines APS-2. AIT associated to other autoimmune diseases (excluding AD and/or hypoparathyroidism) are the main characteristics of APS-3. Different clinical combinations of autoimmune diseases which were not included in the previous groups are the characteristics of APS-4. IPEX is a recessive disorder characterized by the neonatal onset of T1D, infections, enteropathy, thrombocytopenia and anemia, as well as endocrinopathy, eczema and cachexia. These disorders are not common, but their consequences can be life threatening when the diagnosis is overlooked, and the treatment is the same prescribed for isolated disease presentation.
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PMID:[Type 1 diabetes and autoimmune polyendocrine syndromes]. 1843 30

Fanconi anaemia (FA) is an autosomal recessive and X-linked disease characterized by severe genetic instability and increased incidence of cancer. One explanation for this instability may be the cellular hypersensitivity to oxidative stress leading to chromosomal breaks. This study explored the possible oxidative damage to telomeres of FA lymphocyte cell line, HSC536/N, and its possible effect on telomere function. We postulated that combination of oxidative damage with overexpression of telomerase may provide a possible model for malignant transformation in FA. The cells were grown in the presence of telomerase inhibitor and exposed for 1 month to H(2)O(2) combined with various antioxidants. This exposure caused shortening of telomere length and damage to the telomere single stranded overhang, which was prevented by several oxidants. This shortening was associated with development of severe telomere dysfunction. Control cells did not exhibit this sensitivity to H(2)O(2). Telomere dysfunction did not evoke damage response in FA cells, in contrast to normal P53 upregulation in control cells. Reconstitution of telomerase activity protected FA telomeres from further oxidative damage. These results suggest a scenario in which oxidative stress causes telomere shortening and ensuing telomere dysfunction may form the basis for malignant transformation in FA cells. Upregulation of telomerase activity in sporadic FA cells may perpetuate that process, thus explaining the malignant character of FA cells in vivo.
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PMID:Oxidative stress causes telomere damage in Fanconi anaemia cells - a possible predisposition for malignant transformation. 1847 50

GATA-1 is one of the six members of the GATA gene family, a group of related transcription factors discovered in the 1980s. In the past few decades, the crucial role of GATA-1 in normal human hematopoiesis has been delineated. As would be expected, mutations in GATA-1 have subsequently been found to have important clinical significance, and are directly linked to deregulated formation of certain blood cell lineages. This paper reviews the functional consequences of GATA-1 mutations by linking specific errors in the gene, or its downstream protein products, to documented human diseases. These five human diseases are: X-linked thrombocytopenia (XLT), X-linked thrombocytopenia with thalassemia (XLTT), congenital erythropoietic porphyria (CEP), transient myeloproliferative disorder (TMD) and acute megarakaryoblastic leukemia (AMKL) associated with Trisomy 21, and, lastly, a particular subtype of anemia associated with the production of GATA-1s, a shortened, mutant isoform of the wild-type GATA-1. The different phenotypic expressions associated with GATA-1 mutations illustrate the integral function of the transcription factor in overall body homeostasis. Furthermore, these direct genotype-phenotype correlations reinforce the importance of unraveling the human genome, as such connections may lead to important therapeutic or preventive therapies.
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PMID:Human phenotypes associated with GATA-1 mutations. 1893 Jan 24

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder of hematopoietic stem cells. PNH is related to a somatic mutation in the phosphatidylinositol glycan class A (PIG-A), X-linked gene, responsible for a deficiency in glycosylphosphatidylinositol-anchored proteins (GPI-AP). The lack of one of the GPI-AP complement regulatory proteins (CD59) leads to haemolysis. The disease is diagnosed with haemolytic anemia, marrow failure or episodes of venous thrombosis. The diagnosis is based on flow cytometry, which allowed direct quantification of the GPI-AP-deficient cells. From earlier descriptions, the clinical polymorphism of PNH has been recognized by two presentations; one form, predominantly haemolytic without overt marrow failure, referred to classic PNH and the other one, with marrow failure, was often described as the aplastic anemia PNH syndrome (AA-PNH). Thromboses remain a major life threatening complication affecting outcomes in both disease subcategories. Thrombotic events are characterized by involvement of unusual sites (hepatic, mesenteric, cerebral, dermal veins). In classic PNH, recent studies have focused on inhibiting the complement cascade with encouraging clinical results using eculizumab, a C5-inhibitor humanized monoclonal antibody. Concerning the AA-PNH syndrome, bone marrow transplantation (BMT) is the reference treatment in young patients with a sibling donor. Immunosuppressive therapy remains an important treatment modality in this subcategory for patients without a donor or ineligible for BMT. Recurrent thrombotic events remains even now associated with bad prognosis, whatever the form of the disease.
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PMID:[Paroxysmal nocturnal hemoglobinuria]. 1930 77

Fanconi anemia (FA) is a rare autosomal recessive or X-linked disorder characterized by aplastic anemia, cancer susceptibility and cellular sensitivity to DNA-crosslinking agents. Eight FA proteins (FANCA, -B, -C, -E, -F, -G, -L and -M) and three non-FA proteins (FAAP100, FAAP24 and HES1) form the FA nuclear core complex that is required for monoubiquitination of the FANCD2-FANCI dimer upon DNA damage. The other three FA proteins, FANCD1/BRCA2, FANCJ/BACH1/BRIP1 and FANCN/PALB2, act in parallel or downstream of the FANCD2-FANCI dimer. Despite the isolation and characterization of several FA proteins, the mechanism by which these proteins protect cells from DNA interstrand crosslinking agents has been unclear. This is because a majority of the FA proteins lack any recognizable functional domains that can provide insight into their function. The recently discovered FANCM (Hef) and FANCJ (BRIP1/BACH1) proteins contain helicase domains, providing potential insight into the role of FA proteins in DNA repair. FANCM with its partner, FAAP24, and FANCJ bind and metabolize a variety of DNA substrates. In this review, we focus on the discovery, structure, and function of the FANCM-FAAP24 and FANCJ proteins.
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PMID:FANCM-FAAP24 and FANCJ: FA proteins that metabolize DNA. 1937 63


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