Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report a 16-year-old growth deficient boy with craniosynostosis, radial hypoplasia and hypoplastic thumbs. These findings are consistent with the autosomal recessively inherited Baller-Gerold syndrome (BGS) which furthermore shows a great variability of concomitant occasional anomalies. At the age of 16 years our patient suffered from an osteosarcoma of the left distal femur. The occurrence of malignancies has not yet been reported in the hitherto described 22 patients with BGS.
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PMID:Osteosarcoma in a 16-year-old boy with Baller-Gerold syndrome. 760 24

Mutations in a human RecQ helicase homologue, RECQL4, have been identified in patients with Type II Rothmund-Thomson syndrome (RTS) with osteosarcoma predisposition, RAPADILINO syndrome, and Baller-Gerold syndrome. A role in DNA replication initiation has been demonstrated and mapped to the amino terminus upstream of the helicase domain; however, no nuclear localization signal (NLS) has been identified by sequence analysis. Here, we show both endogenous and green fluorescent protein (GFP)-tagged RECQL4 are nuclear and cytoplasmic in transformed cell lines. Using GFP-tagged constructs we identified a major nuclear localization domain within amino acids (aa) 363-492 (exons 5-8) sufficient for nuclear localization of GFP and necessary for nuclear localization of RECQL4 as GFP-RECQL4 deleted for aa 363-492 is entirely cytoplasmic. Additional mapping within this domain revealed that a conserved block of 22 basic amino acids (aa 365-386; exons 5-6) is sufficient for nuclear localization of GFP, but not required for nuclear import of RECQL4. Conversely, even though the region encoded by exon 7-8 is not sufficient for nuclear import of GFP, GFP-RECQL4 deleted for exon 7 (aa 420-463), a mutation found in all reported patients with RAPADILINO syndrome, is cytoplasmic. Nuclear localization of the exon 7 deletion construct is increased in cells treated with leptomycin B suggesting that exon 7 encodes a domain required for nuclear retention of RECQL4. This retention activity is partially conveyed by a conserved VLPLY motif (aa 450-454) in exon 7 of the human sequence. In summary, unlike other RecQ proteins with carboxyl terminal NLS, RECQL4 nuclear localization and retention activities are amino terminal. This location would provide nuclear transport of putative truncated proteins encoded by RTS mutant alleles consistent with the proposed essential replication function in the amino terminus of RECQL4.
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PMID:Nuclear import and retention domains in the amino terminus of RECQL4. 1725 Sep 75

Mutations in the RECQL4 gene can lead to three clinical phenotypes with overlapping features. All these syndromes, Rothmund-Thomson (RTS), RAPADILINO and Baller-Gerold (BGS), are characterized by growth retardation and radial defects, but RAPADILINO syndrome lacks the main dermal manifestation, poikiloderma that is a hallmark feature in both RTS and BGS. It has been previously shown that RTS patients with RECQL4 mutations are at increased risk of osteosarcoma, but the precise incidence of cancer in RAPADILINO and BGS has not been determined. Here, we report that RAPADILINO patients identified as carriers of the c.1390+2delT mutation (p.Ala420_Ala463del) are at increased risk to develop lymphoma or osteosarcoma (6 out of 15 patients). We also summarize all the published RECQL4 mutations and their associated cancer cases and provide an update of 14 novel RECQL4 mutations with accompanying clinical data.
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PMID:The mutation spectrum in RECQL4 diseases. 1871 13

Rothmund-Thomson syndrome (RTS) is a genodermatosis presenting with a characteristic facial rash (poikiloderma) associated with short stature, sparse scalp hair, sparse or absent eyelashes and/or eyebrows, juvenile cataracts, skeletal abnormalities, radial ray defects, premature aging and a predisposition to cancer. The prevalence is unknown but around 300 cases have been reported in the literature so far. The diagnostic hallmark is facial erythema, which spreads to the extremities but spares the trunk, and which manifests itself within the first year and then develops into poikiloderma. Two clinical subforms of RTS have been defined: RTSI characterised by poikiloderma, ectodermal dysplasia and juvenile cataracts, and RTSII characterised by poikiloderma, congenital bone defects and an increased risk of osteosarcoma in childhood and skin cancer later in life. The skeletal abnormalities may be overt (frontal bossing, saddle nose and congenital radial ray defects), and/or subtle (visible only by radiographic analysis). Gastrointestinal, respiratory and haematological signs have been reported in a few patients. RTS is transmitted in an autosomal recessive manner and is genetically heterogeneous: RTSII is caused by homozygous or compound heterozygous mutations in the RECQL4 helicase gene (detected in 60-65% of RTS patients), whereas the aetiology in RTSI remains unknown. Diagnosis is based on clinical findings (primarily on the age of onset, spreading and appearance of the poikiloderma) and molecular analysis for RECQL4 mutations. Missense mutations are rare, while frameshift, nonsense mutations and splice-site mutations prevail. A fully informative test requires transcript analysis not to overlook intronic deletions causing missplicing. The diagnosis of RTS should be considered in all patients with osteosarcoma, particularly if associated with skin changes. The differential diagnosis should include other causes of childhood poikiloderma (including dyskeratosis congenita, Kindler syndrome and Poikiloderma with Neutropaenia), other rare genodermatoses with prominent telangiectasias (including Bloom syndrome, Werner syndrome and Ataxia-telangiectasia) and the allelic disorders, RAPADILINO syndrome and Baller-Gerold syndrome, which also share some clinical features. A few mutations recur in all three RECQL4 diseases. Genetic counselling should be provided for RTS patients and their families, together with a recommendation for cancer surveillance for all patients with RTSII. Patients should be managed by a multidisciplinary team and offered long term follow-up. Treatment includes the use of pulsed dye laser photocoagulation to improve the telangiectatic component of the rash, surgical removal of the cataracts and standard treatment for individuals who develop cancer. Although some clinical signs suggest precocious aging, life expectancy is not impaired in RTS patients if they do not develop cancer. Outcomes in patients with osteosarcoma are similar in RTS and non-RTS patients, with a five-year survival rate of 60-70%. The sensitivity of RTS cells to genotoxic agents exploiting cells with a known RECQL4 status is being elucidated and is aimed at optimizing the chemotherapeutic regimen for osteosarcoma.
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PMID:Rothmund-Thomson syndrome. 2011 79