Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ataxia-telangiectasia (AT) is an autosomal recessive disorder characterized by cerebellar ataxia, oculocutaneous telangiectasia, immune deficiency, genome instability and predisposition to malignancies, particularly T-cell neoplasms. The responsible gene, designated ataxia-telangiectasia mutated (ATM), was recently identified by positional cloning in the chromosomal region 11q22.3-23.1 (ref. 4, 5) ATM is 150 kb in length, consists of 66 exons and encodes a nuclear phosphoprotein of approximately 350 kDa (ref. 4-9). Although ATM is considered to be a tumorigenic factor in several human cancers, it has not yet been found mutated in tumors of non-AT patients. Given the marked predisposition of AT patients to develop neoplasms of the T-cell lineage, we analyzed a series of T-cell leukemias (T-prolymphocytic leukemia, or T-PLL) in non-AT patients in search of genomic changes associated with the development of this disease. Among the recurrent aberrations identified, deletion of the chromosome arm 11q was very frequent. Subsequent molecular cytogenetic analyses allowed us to define a small commonly deleted segment at 11q22.3-23.1 in 15 of 24 T-PLLs studied. Since this critical region contained ATM, we further analyzed the remaining copy of the gene in six cases showing deletions affecting one ATM allele. In all six cases, mutations of the second ATM allele were identified, leading to the absence, premature truncation or alteration of the ATM gene product. Thus, our study demonstrates disruption of both ATM alleles by deletion or point mutation in T-PLL, suggesting that ATM functions as a tumor-suppressor gene in tumors of non-AT individuals.
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PMID:Biallelic mutations in the ATM gene in T-prolymphocytic leukemia. 933 31

Paraneoplastic cerebellar degeneration is a rare remote effect of ovarian and breast carcinoma especially, and is characterised clinically by rapidly evolving pancerebellar symptoms. A woman aged 83 developed progressive vertigo, cerebellar ataxia, nystagmus and dysarthria. The cerebrospinal fluid showed slight mononuclear pleocytosis, elevated total protein and IgG concentrations, and oligoclonal bands. A magnetic resonance investigation performed within the first month of symptoms was normal. A left pelvic mass was found, possibly a carcinoma of the colon or the left ovary. Cancer antigen 125 was elevated in the serum and antibodies against Purkinje cells (anti-Yo antibodies) were demonstrated in the serum and cerebrospinal fluid. These results suggested a carcinoma of the ovary as primary site of cancer. Autopsy revealed a left ovarian adenocarcinoma and marked loss of Purkinje cells in the cerebellum. The case illustrates that anti-Yo antibodies may serve as a marker not only for paraneoplastic cerebellar degeneration, but also for the nature of the neoplasm that caused it.
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PMID:[Paraneoplastic cerebellar degeneration. A case report]. 934 Aug 52

Ataxia telangiectasia (AT) is an autosomal recessive disorder characterized by growth retardation, cerebellar ataxia, oculocutaneous telangiectasias, and a high incidence of lymphomas and leukemias. In addition, AT patients are sensitive to ionizing radiation. Atm-deficient mice recapitulate most of the AT phenotype. p21(cip1/waf1 )(p21 hereafter), an inhibitor of cyclin-dependent kinases, has been implicated in cellular senescence and response to gamma-radiation-induced DNA damage. To study the role of p21 in ATM-mediated signal transduction pathways, we examined the combined effect of the genetic loss of atm and p21 on growth control, radiation sensitivity, and tumorigenesis. As might have been expected, our data provide evidence that p21 modifies the in vitro senescent response seen in AT fibroblasts. Further, it is a downstream effector of ATM-mediated growth control. In addition, however, we find that loss of p21 in the context of an atm-deficient mouse leads to a delay in thymic lymphomagenesis and an increase in acute radiation sensitivity in vivo (the latter principally because of effects on the gut epithelium). Modification of these two crucial aspects of the ATM phenotype can be related to an apparent increase in spontaneous apoptosis seen in tumor cells and in the irradiated intestinal epithelium of mice doubly null for atm and p21. Thus, loss of p21 seems to contribute to tumor suppression by a mechanism that operates via a sensitized apoptotic response. These results have implications for cancer therapy in general and AT patients in particular.
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PMID:Loss of p21 increases sensitivity to ionizing radiation and delays the onset of lymphoma in atm-deficient mice. 940 57

Type 1 antineuronal nuclear autoantibody (ANNA-1, also known as "anti-Hu") is a marker of neurologic autoimmunity that is highly associated with small-cell lung carcinoma (SCLC). To determine the spectrum of symptoms and signs as well as the frequency of cancer in adult patients who are seropositive for ANNA-1, we reviewed 162 sequential patients (67% female) identified as ANNA-1-positive in a comprehensive immunofluorescence screening test. In 21% of these patients, the antibody test requested by the physician was not ANNA-1. By the end of the follow-up period, cancer had been found in 142 patients (88%). Ten of these lacked evidence of SCLC (4 had prostate carcinoma, 3 breast carcinoma, 1 both prostate carcinoma and melanoma, 1 lymphoma, and 1 squamous-cell lung carcinoma). Of the 132 patients (81%) with proven SCLC, 17 had one or more coexisting malignant neoplasms (6 had renal carcinoma, 4 another lung primary carcinoma, 3 prostate carcinoma, 3 breast carcinoma, and 4 assorted neoplasms). The diagnosis of SCLC in 128 patients (97%) followed the onset of paraneoplastic symptoms. SCLC was identified in 10 patients by chest MRI after an equivocal chest radiograph or CT; in 28 by bronchoscopy, mediastinoscopy, or thoracotomy; and in 7 at autopsy. Neurologic signs in decreasing frequency were neuropathy (sensory > mixed somatic > autonomic > cranial [especially cranial nerve VIII] > motor), cerebellar ataxia, limbic encephalitis, polyradiculopathy, associated Lambert-Eaton myasthenic syndrome, myopathy, myelopathy, opsoclonus/myoclonus, motor neuronopathy, brachial plexopathy, and aphasia. Nineteen patients had a solely gastrointestinal initial presentation, including gastroparesis, pseudo-obstruction, esophageal achalasia, or other dysmotility. We conclude that seropositivity for ANNA-1 can expedite the diagnosis and treatment of otherwise occult cancer in patients, especially tobacco abusers, with varied neurologic and gastroenterologic presentations. The search for SCLC should not end on discovering a different neoplasm.
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PMID:Paraneoplastic and oncologic profiles of patients seropositive for type 1 antineuronal nuclear autoantibodies. 952 Dec 51

Ataxia-telangiectasia is a multisystem recessive disease characterized clinically by cerebellar ataxia, oculocutaneous telangiectasias, immunodeficiency, sensitivity to radiomimetic agents and an increased predisposition to cancer. This pleiotropic disorder is caused by mutations in the ATM gene, which is located at the human chromosomal region 11q23. Loss of heterozygosity (LOH) at 11q22-q23 is a frequent event in ovarian cancer, suggesting the presence of a tumor suppressor gene in this region. We have found that LOH in the ATM gene occurred in 44% of informative cases in a series of 22 primary ovarian tumors. LOH of this region occurred at the same frequency during the advanced stages (III-IV; 3/9, 33%) as in the early stages (I-II; 4/13, 31%) of ovarian cancer. To investigate the role of ATM in ovarian cancer, we used a PCR-based single-strand conformation polymorphism assay for mutation detection of the entire coding sequence of the ATM gene (65 exons) in 22 ovarian tumors. No somatic alterations of the ATM gene were found in these ovarian cancer samples including those with LOH present in the ATM gene. Our study has identified a region (11q23) which probably contains a frequently altered tumor suppressor gene in ovarian cancer, and this gene does not appear to involve the coding sequences of the ATM gene.
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PMID:Ovarian cancer: loss of heterozygosity frequently occurs in the ATM gene, but structural alterations do not occur in this gene. 994 3

Paraneoplastic cerebellar degeneration (PCD) is a clinical syndrome and known to be occasionally associated with small cell carcinoma of the lung (SCLC). PCD usually affects patients before the cancer is evident. The disorder evolves subacutely, and causes severe pancerebellar dysfunction. In this paper, we report a case of PCD associated with SCLC. A 65-year-old man presenting with 2 weeks of progressive vertigo, gait ataxia, and speech disturbance, was readmitted to our hospital. He had earlier been given a diagnosis of SCLC, oat cell carcinoma, and had undergone high-dose chemotherapy with peripheral blood stem cell transplantation during his first admission. Following that treatment regimen, the tumor disappeared completely and the patient had been in remission. Based on neurological findings and the presence of anti-neuronal antibodies a diagnosis of PCD was made. Although cyclophosphamide (500 mg/m2) was administered, the patient experienced no relief of his cerebellar ataxia. Six months afer readmission, he died of cardiac tamponade due to malignant pericarditis. A histological examination at autopsy found few Purkinje cells and a proliferation of Bergmann's astrocytes in the cerebellar cortex. These findings were consistent with the diagnosis of PCD.
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PMID:[A case of paraneoplastic cerebellar degeneration associated with small cell lung cancer]. 1021 46

We report a case of cerebellar astrocytoma occurring 8 years after the second bone marrow transplantation (BMT) in 32-year-old man. The patient was admitted to our hospital in December 1997 because of dysarthria and gait disturbance. He had been treated earlier for acute myeloid leukemia (AML M2) with chemotherapy and cranial irradiation followed by allogeneic BMT from a sibling in december 1988. Three months after the first BMT, testicular relapse was observed and followed by systemic relapse. The patient received reinduction therapy and a second successful BMT. He had been well until about 1 month before admission to our hospital. Neurological examination revealed left cerebellar ataxia, and brain magnetic resonance imaging disclosed a left cerebellar tumor. The tumor was surgically resected and a histological diagnosis of cerebellar astrocytoma was made. The patient was further treated by irradiation for residual tumor and discharged without progression of the disease.
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PMID:[Development of cerebellar astrocytoma in a patient with acute myeloid leukemia 8 years after his second bone marrow transplant]. 1039 Aug 94

A 72-year-old man developed left facial palsy at age 14 and left-sided hearing loss at age 20. At the age of 59, he presented with gait disturbance, and a large left cerebellopontine angle tumor was detected, which had markedly destroyed the pyramidal bone. The tumor was subtotally resected, but he required two more operations at the ages of 64 and 69 because of tumor regrowth. At the present time, recurrent tumor has destroyed the occipital bone and is invading the scalp. However, even though he has several cranial nerve palsies and cerebellar ataxia, he remains in stable condition and demonstrates long-term survival. The patient's surgical specimens revealed a papillary adenoma, which was recently thought to be of endolymphatic sac origin, although the origin of this kind of tumor, whether arising from the middle ear or from the endolymphatic sac, has not been established with certainty so far. In this paper, we provide further evidence that this tumor originates from the endolymphatic sac, based on anatomical, histopathological, and embryological evidence.
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PMID:A case of endolymphatic sac tumor with long-term survival. 1074 63

An 11-year-old boy admitted with a right cervical mass was found to have Hodgkin disease. On admission, he also had right Homer syndrome and severe cerebellar ataxia. Cranial MRI revealed marked cerebellar atrophy. He was treated with chemotherapy consisting of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD), in addition to radiotherapy. Three months after initiation of therapy, he had a partial remission of tumor. Neurologic symptoms improved dramatically after chemotherapy started. Hodgkin disease should be included in the differential diagnosis of children with cerebellar findings and Horner syndrome.
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PMID:Paraneoplastic cerebellar degeneration and Horner syndrome: association of two uncommon findings in a child with Hodgkin disease. 1077 31

The human genetic disorder ataxia-telangiectasia is characterized by immunodeficiency, progressive cerebellar ataxia, radiosensitivity, cell cycle checkpoint defects, and cancer predisposition. The gene product [ataxia-telangiectasia mutation (ATM)] mutated in this syndrome is a component of the DNA damage detection pathway. Loss of ATM function in human and mouse cells causes defects in DNA repair and cell cycle checkpoint control and, not surprisingly, humans and mice with compromised ATM function are prone to cancers. An excess of breast cancer in the relatives of ataxia-telangiectasia patients has also been reported by epidemiological studies. Predisposition to breast and ovarian cancers is also observed in women with germline mutations in BRCA1, a tumor suppressor gene. BRCA1 is a nuclear protein with a cell cycle-regulated expression pattern and is hyperphosphorylated in response to DNA-damaging agents. Here we show that rapid ionizing radiation-induced in vivo phosphorylation of BRCA1 requires the presence of functional ATM protein. Furthermore, we show that ATM interacts with BRCA1, and this association is enhanced by radiation. We also demonstrate that BRCA1 is a substrate of ATM kinase in vitro and in vivo. Using phospho-specific antibodies against serines 1387, 1423, and 1457 of BRCA1, we demonstrate radiation-induced, ATM-dependent phosphorylation of BRCA1 at these sites. These findings show that BRCA1 is regulated by an ATM-dependent mechanism as a part of the cellular response to DNA damage. This interaction between ATM and BRCA1 argues in favor of the involvement of particular aspects of ATM function in breast cancer predisposition.
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PMID:Role for ATM in DNA damage-induced phosphorylation of BRCA1. 1086 24


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