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)

Alpha1-fetoprotein (AFP) is an alpha1-glycoprotein which can be found in high concentration during fetal development in many mammals, birds, sharks and, also, man. The alpha-fetoproteins of various species have similar physico-chemical properties and often common antigenic determinants. Differences of microheterogeneity depend on a different content of sialin-acid. During human fetal development the serum AFP concentration falls with increasing gestational age. 4-5 weeks after birth AFP can be detected usually in low serum concentrations. Using more sensitive immunulogic techniques e.g. radioimmunoassay there was shown that AFP is present in sera of normal adults in concentrations of 10-20 ng/ml. AFP serum concentrations rise physiologically during pregnancy up to 500-550 ng/ml. During fetal development liver, yolk sac and gastrointestinal tract are the major sites of synthesis. In primary liver cell carcinoma, hepatoblastoma and in teratoblastoma containing yolk sac tissue AFP synthesis rises in tumor cells; the AFP serum concentration increases above 2 microgram/ml. In patients with benign liver diseases e.g. virus hepatitis, a transient rise of AFP serum concentrations was seen. Moreover, increased levels of AFP were found in hereditary diseases e.g. congenital tyrosinemia, ataxia-telangiectasia and in the amniotic fluid in congenital nephrosis of Finnish type. AFP assay in serum is clinically important for the control of course and treatment of primary liver cell carcinoma and teratoblastoma. AFP assay in amniotic fluid is a method for the prenatal detection of neural tube defects and the fetal distress syndrome, especially.
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PMID:[Alpha1-fetoprotein: physiology, pathology and diagnosis especially in childhood (author's transl)]. 7 May 46

The biologic peculiarities of tumors of early life are elucidated. The oncogenic grace period is emphasized, wherein infantile tumors tend to behave in a relatively benign fashion up until 3-6 months of age. A review of the types of congenital malformations associated with the development of neoplasms is presented. These associations appear to be of fundamental importance in developmental pathobiology. They are illustrated by the tendency for neoplasms to develop in anomalous or dysplastic tissues, such as developmental vestiges, undescended testes, dysgenic gonads and certain hamartoses. There is an increased incidence of tumor occurrence in: (1) specific teratologic disorders: aniridia, hemihypertrophy, Beckwith's syndrome, basal cell nevus syndromes and others; (2) cytogenetic abnormalities: Down's syndrome, 13q- syndrome (D-deletion), trisomy 18; (3) chromosomal instability syndromes: Fanconi's anemia, ataxia-telangiectasia, Bloom's syndrome. Finally, many agents, known to be carcinogenic when administered postnatally to animals, are teratogenic in the fetus. A few agents--urethan, alkylnitrosoureas, estrogens--are both teratogenic and carcinogenic when administered to the fetus transplacentally. It is suggested that the timing of intrauterine insult is important in determining whether the effect on the offspring is teratogenic, oncogenic or both. Teratogenesis appears to be the more primitive response. Other theories explaining the concurrence of tumors and anomalies are offered.
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PMID:Neoplasia of early life and its relationships to teratogenesis. 18 28

Cellular and humoral immunity, and lymphoid organ pathology, have been investigated in 10 institutionalized patients with tuberous sclerosis and 10 institutionalized matched controls without the disease. Type and incidence of infections and tumours were reviewed for each group, as was current medication. Elevated serum IgM levels were found in the patients with tuberous sclerosis, but no immunological deficiency of either cellular of humoral immunity was found, nor was there a difference in infection between the groups. Only patients with tuberous sclerosis had evidence of neoplasia. No morphological or histological abnormalities of lymph nodes, spleen or thymus were present. Explanations for the difference between tuberous sclerosis and ataxia telangiectasia are discussed, together with the effect of immuno-surveillance on the development of malignancy.
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PMID:Immunological status in tuberous sclerosis. 95 13

The neuropathologic findings in a 17-year-old boy with ataxia-telangiectasia are described. In agreement with previous reports, pathologic changes were present in the cerebellum, spinal cord, dorsal root ganglia, and straited muscle. The lesions in the spinal cord and dorsal root ganglia were more severe than previously described. Abnormalities were also seen in several brain stem nuclei, including the mesencephalic nucleus of the trigeminus and the substantia nigra. In addition, a small hamartomatous tumor was found in that thalamus.
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PMID:Neuropathologic changes in ataxia-telangiectasia. 98 86

Although neoplasms are unusually frequent in patients with ataxia-telangiectasia, the occurrence of primary tumors of the ovary in such patients is exceedingly rare. This report describes a 17-year-old phenotypic female with ataxia-telangiectasia, who was found to harbor an ovarian gonadoblastoma and a contralateral dysgerminoma. The latter tumor has occurred in only one other patient with ataxia-telangiectasia, while an association with gonadoblastoma has never been documented previously. Additional unusual features rarely encountered in patients with gonadoblastoma included origin of the tumor within a histologically proven ovary, and a 46,XX karyotype. The possibility that the dysgerminoma also arose from a gonadoblastoma is discussed.
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PMID:Ataxia-telangiectasia with ovarian gonadoblastoma and contralateral dysgerminoma. 119 68

We established a clonal T-cell line with a reciprocal chromosomal translocation t(14;18)(q11;q23) from a patient with ataxia telangiectasia (AT) and T-cell chronic lymphocytic leukemia (T-CLL). The tumor cells and the derived T-cell line were compared with respect to phenotype, karyotype, and rearrangement pattern. Restriction fragment analyses of the T-cell receptor (TCR)-delta gene, which is located within the TCR-alpha gene on chromosome 14q11, indicated that the breakpoint is located within the TCR-delta locus, splitting the TCR-delta gene between the variable and joining segments. This specific chromosomal translocation was only detected in the derived T-cell line and may be involved in the genesis of T-cell malignancies in AT.
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PMID:Molecular analysis of an ataxia telangiectasia T-cell clone with a chromosomal translocation t(14;18)--evidence for a breakpoint in the T-cell receptor delta-chain gene. 135 32

The familial occurrence of head and neck cancers supports the role of heredity in this disease group. The roles of environmental and genetic factors are difficult to separate. There are several well-characterized entities, however, that are associated with risk and prognosis of head and neck cancer, including Lynch-II syndrome, Bloom syndrome, Fanconi's anemia, xeroderma pigmentosum, ataxia telangiectasia, and Li-Fraumeni syndrome. Mutagen-induced chromosomal damage is associated with an increased risk of multiple primary neoplasms and upper aerodigestive tract cancers. A possible reduction of genotoxicity, mediated by micronutrients, was demonstrated in vitro. Sister chromatid exchanges and micronuclei are useful exposure and disease markers. Metabolic changes (acetylation, DBQ phenotype, and the AH locus polymorphism) have been found to be associated with cancer of the upper aerodigestive tract. Most associations between histocompatibility antigens and solid tumors are relatively weak, probably because of the masking effects of environmental factors. Infections by HPV, EBV, and HSV have a causative or predisposing role in several types of head and neck cancer. Amplification and rearrangement of oncogenes may also play a role in carcinogenesis, and oncogene amplification may be associated with aggressive tumor behavior and unfavorable clinical prognosis. Ploidy of tumors seems to be an important determinant of survival and response to therapy.
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PMID:Hereditary and environmental factors associated with risk and progression of head and neck cancer. 140 93

Cell cycle checkpoints can enhance cell survival and limit mutagenic events following DNA damage. Primary murine fibroblasts became deficient in a G1 checkpoint activated by ionizing radiation (IR) when both wild-type p53 alleles were disrupted. In addition, cells from patients with the radiosensitive, cancer-prone disease ataxia-telangiectasia (AT) lacked the IR-induced increase in p53 protein levels seen in normal cells. Finally, IR induction of the human GADD45 gene, an induction that is also defective in AT cells, was dependent on wild-type p53 function. Wild-type but not mutant p53 bound strongly to a conserved element in the GADD45 gene, and a p53-containing nuclear factor, which bound this element, was detected in extracts from irradiated cells. Thus, we identified three participants (AT gene(s), p53, and GADD45) in a signal transduction pathway that controls cell cycle arrest following DNA damage; abnormalities in this pathway probably contribute to tumor development.
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PMID:A mammalian cell cycle checkpoint pathway utilizing p53 and GADD45 is defective in ataxia-telangiectasia. 142 16

Heterogeneity of response of tumor tissue to radiation clearly exists. Major parameters include histopathologic type, size (number of tumor rescue units (TRUs)), hemoglobin concentration, cell proliferation kinetics and immune rejection reaction by host. Further, normal and presumably tumor tissue response is altered in certain genetic diseases, e.g. ataxia telangiectasia. Any assessment of response of tumor tissue to a new treatment method or the testing of a new clinical response predictor is optimally based upon a narrow strata, viz., uniform with respect to known parameters of response, e.g. size, histological type. Even among tumors of such a clinically defined narrow strata, there will be residual heterogeneity with respect to inherent cellular radiation sensitivity, distributions of pO2, (SH), cell proliferation etc. The value of a response predictor of an individual tumor will be determined by the heterogeneity of values for these and or other characteristics and by the coefficient of variation (CV) of the measured values of the individual parameters. Heterogeneity of one or more parameters of response is reflected in the slope of the dose response curve for local control, viz. the greater the heterogeneity the less steep the slope. To examine for this effect, the slope of dose response curves for control of model tumors of 10(8) tumor rescue units (TRU) and the SF2 = 0.5 (survival fraction after a single dose of 2 Gy) has been used to assess the impact of inter- and intra-tumoral variation of SF2 on slope, defined as gamma 50 values. The gamma 50 is the increase in local control expressed in percent points for a one percentage increment in dose, at the mid-point on the dose-response curve. The gamma 50 was 6.5 for CV = 0.0. For inter-tumoral CVs of 10%, 20% and 40%, the gamma 50 rapidly decreased to 2.4, 1.3 and 0.7. Intra-tumoral variation was less important, viz., for CVs of 10%, 20%, and 40% the gamma 50 values were reduced to 5.3, 3.8 and 2.2. Combining inter- and intra-tumoral variation reduced the gamma 50 only slightly below that for inter-tumoral variation alone. For example, were the CV 10% for inter- and intra-tumoral variation, the gamma 50 would be 2.1 as compared to 2.4 for inter-tumoral variation alone. The number of TRUs also affects slope, viz. gamma 50 increased from 1 to 9.7 as the TRU number increased from 10(1) to 10(12).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Clinical implications of heterogeneity of tumor response to radiation therapy. 148 Jul 70

Hereditary breast cancer is common and accounts for approximately 10-14% of all breast cancers. Knowledge of a family history of breast cancer may significantly influence diagnosis and therapy. Genetic heterogeneity has been demonstrated in familial breast cancer. Recently inherited mutations in the tumor suppressor gene p53, have been shown to be the underlying defect in the Li-Fraumeni syndrome. We have shown that defects in this gene also play a role in the predisposition to other familial breast cancers. The gene responsible for early onset familial breast and ovary cancer has recently been mapped to chromosome 17q21. For most of the sporadic breast cancers a multifactorial model, including variable genetic and environmental factors, has been considered. Two genetic risk factors which may predispose for a considerable portion of breast cancers are the gene causing ataxia telangiectasia (AT) and the gene that gives rise to proliferative breast disease (PBD). Identification of distinct genes enhancing the risk of breast cancer will give us the opportunity to identify high risk individuals. Such individuals may benefit from periodic examination affording the possibility of early diagnosis and treatment.
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PMID:Role of genetic factors in breast cancer susceptibility. 162 29


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