Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Many cancers have been cured by chemotherapeutic agents. However, other cancers are intrinsically drug resistant, and some acquire resistance following chemotherapy. Cloning of the cDNA for the human MDR1 gene (also known as PGY1), which encodes the multidrug efflux protein P-glycoprotein, has made it possible to measure levels of MDR1 RNA in human cancers. We report the levels of MDR1 RNA in greater than 400 human cancers. MDR1 RNA levels were usually elevated in untreated, intrinsically drug-resistant tumors, including those derived from the colon, kidney, adrenal gland, liver, and pancreas, as well as in carcinoid tumors, chronic myelogenous leukemia in blast crisis, and cell lines of non-small cell carcinoma of the lung (NSCLC) with neuroendocrine properties. MDR1 RNA levels were occasionally elevated in other untreated cancers, including neuroblastoma, acute lymphocytic leukemia (ALL) in adults, acute nonlymphocytic leukemia (ANLL) in adults, and indolent non-Hodgkin's lymphoma. MDR1 RNA levels were also increased in some cancers at relapse after chemotherapy, including ALL, ANLL, breast cancer, neuroblastoma, pheochromocytoma, and nodular, poorly differentiated lymphoma. Many types of drug-sensitive and drug-resistant tumors, including NSCLC and melanoma, contained undetectable or low levels of MDR1 RNA. The consistent association of MDR1 expression with several intrinsically resistant cancers and the increased expression of the MDR1 gene in certain cancers with acquired drug resistance indicate that the MDR1 gene contributes to multidrug resistance in many human cancers. Thus, evaluation of MDR1 gene expression may prove to be a valuable tool in the identification of individuals whose cancers are resistant to specific agents. The information may be useful in designing or altering chemotherapeutic protocols in these patients.
 ...
PMID:Expression of a multidrug resistance gene in human cancers. 256 56

Marrow transplantation is effective treatment for a number of hematological diseases in patients under the age of 50 who have an HLA-identical sibling donor. It is successful in the treatment of aplastic anemia with 70-85% long-term survival. It offers 10-30% apparent cures for patients with acute leukemia who have relapsed at least once, and for those with chronic myelocytic leukemia in blast crisis. Although still somewhat controversial, it appears to be the treatment of choice for patients with acute nonlymphoblastic leukemia in first chemotherapy induced remission, and for those with chronic myelogenous leukemia in the chronic phase since approximately 50-60% of these patients experience long-term, disease-free survival. Patients with acute lymphoblastic leukemia grafted in second or subsequent remission may expect a 30% "cure" of their disease. Marrow grafting is the only effective treatment for many patients with inherited immunologic deficiencies and certain genetic storage diseases. Cures of congenital Fanconi's anemia, Blackfan-Diamond anemia, osteopetrosis, paroxysmal nocturnal hemoglobinuria and thalassemia major have been achieved. Marrow transplantation is being explored for the therapy of patients with lymphoma, Hodgkin's disease, preleukemia, multiple myeloma, hairy cell leukemia, small cell lung cancer, testicular cancer, ovarian cancer and neuroblastoma. Marrow transplantation has been limited by the fact that many patients do not have HLA-identical siblings and very few have monozygotic twins. More recently, marrow transplants from HLA-nonidentical family members and even from unrelated donors have been successfully explored.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Marrow transplantation: the Seattle experience. 391 47

A monoclonal antibody designated PI153/3, which reacts with neuroblastoma and fetal brain, is shown to identify also a cell surface determinant shared by pre-B and mature B cells and their corresponding leukemias including chronic lymphocytic leukemia, non-Hodgkin's lymphoma, B acute lymphoblastic leukemia, and hairy cell leukemia, but not plasmacytoma. Almost all non-T, non-B acute "lymphoid" leukemias bind PI153/3. The latter includes 71 of 74 common ALL tested, most but not all "unclassified" or "null" ALL and cases of both acute undifferentiated leukemia and Ph1 positive chronic myeloid leukemia in blast crisis with common ALL phenotypes. The antigen is absent or present at very low density on normal and leukemic T lymphocyte, myeloid and erythroid cells. The determinant appears to co-redistribute with cell surface immunoglobulin in B lymphocytes and segregates independently of other cell surface antigens associated with B cells and/or cALL including HLA-DR (Ia-like antigens) and the cALL (gp 100) antigen.
 ...
PMID:A monoclonal antibody identifying a cell surface antigen shared by common acute lymphoblastic leukemias and B lineage cells. 696 98

The activity of IMP dehydrogenase (EC 1.2.1.14), the key enzyme of de novo guanylate biosynthesis, was shown to be increased in tumor cells. Tiazofurin (TR), a potent and specific inhibitor of this enzyme, proved to be effective in the treatment of refractory granulocytic leukemia in blast crisis. We examined the effects of tiazofurin as a single agent and in combination with hypoxanthine and allopurinol in six different neuroectodermal tumor cell lines, the STA-BT-3 and 146-18 human glioblastoma cell lines, the SK-N-SH, LA-N-1 and LA-N-5 human neuroblastoma cell lines, and the STA-ET-1 Ewing tumor cell line. Tiazofurin inhibited tumor cell growth with IC50 values between 2.2 microM (LA-N-1 cell line) and 550 microM (LA-N-5 cells) and caused a significant decrease of intracellular GTP pools (GTP concentrations decreased to 39-79% of control). Incorporation of [8-14C]guanine into GTP pools was determined as a measure of guanylate salvage activity; incubation with 100 microM hypoxanthine caused a 62-96% inhibition of the salvage pathway. Incubation with tiazofurin (100 microM) and hypoxanthine (100 microM) synergistically inhibited tumor cell growth, and the addition of allopurinol (100 microM) strengthened these effects. Therefore, this drug combination, inhibiting guanylate de novo and salvage pathways, may prove useful in the treatment of human neuroectodermal tumors.
 ...
PMID:Synergistic action of tiazofurin with hypoxanthine and allopurinol in human neuroectodermal tumor cell lines. 790 33

The IMP dehydrogenase inhibitor, tiazofurin (TR)-2-beta-D-ribofuranosylthiazole-4-carboxamide, which exhibited oncolytic activity in patients with chronic myelogenous leukaemia (CML) in blast crisis was found to inhibit the growth of human neuroblastoma SK-N-SH cells with an IC50 of 4.2 microM. TR treatment of cells perturbed nucleic acid and catecholamine pathways. As biochemical markers of TR action decreased cellular GTP pools, increased inosine and hypoxanthine concentrations and depleted dopamine content were found. Incubation of tumour specimens obtained from paediatric patients with grade-IV neuroblastoma with TR resulted in the formation of the active metabolite, thiazole-4-carboxamide adenine dinucleotide, in concentrations sufficient to inhibit tumour growth. Cytotoxic and biochemical effects of TR were enhanced by combining it with allopurinol (an inhibitor of xanthine dehydrogenase), and hypoxanthine (an alternate substrate for hypoxanthine-guanine phosphoribosyltransferase). Induction of transdifferentiation of SK-N-SH cells from a neuroblast to an epitheloid, substrate-adherent phenotype was more pronounced with TR than with all-trans-retinoic acid. Transdifferentiating treatment with TR resulted in a 2-fold-enhanced sensitivity towards adriamycin. However, differentiation with all-trans-retinoic acid rendered the cells more resistant to adriamycin. Our results suggest that TR might be a promising agent for the treatment of children suffering from neuroblastoma.
 ...
PMID:Cytotoxicity, differentiating activity and metabolism of tiazofurin in human neuroblastoma cells. 834 56

The PARK2 gene, previously identified as a mutated target in patients with autosomal recessive juvenile parkinsonism (ARJP), has recently been found to be a candidate tumor suppressor gene in ovarian, breast, lung and hepatocellular carcinoma that maps to the third common fragile site (CFS) FRA6E. PARK2 is linked to a novel described PACRG gene by a bidirectional promoter containing a defined CpG island in its common promoter region. We have studied the role of promoter hypermethylation in the regulation of PARK2 and PACRG expression in different tumor cell lines and primary patient samples. Abnormal methylation of the common promoter of PARK2 and PACRG was observed in 26% of patients with acute lymphoblastic leukemia and 20% of patients with chronic myelogenous leukemia (CML) in lymphoid blast crisis, but not in ovarian, breast, lung, neuroblastoma, astrocytoma or colon cancer cells. Abnormal methylation resulted in downregulation of PARK2 and PACRG gene expression, while demethylation of ALL cells resulted in demethylation of the promoter and upregulation of PARK2 and PACRG expression. By FISH, we demonstrated that a lack of PARK2 and PACRG expression was due to biallelic hypermethylation and not to deletion of either PARK2 or PACRG in ALL. In conclusion, our results demonstrate for the first time that the candidate tumor suppressor genes PARK2 and PACRG are epigenetically regulated in human leukemia, suggesting that abnormal methylation and regulation of PARK2 and PACRG may play a role in the pathogenesis and development of this hematological neoplasm.
 ...
PMID:Abnormal methylation of the common PARK2 and PACRG promoter is associated with downregulation of gene expression in acute lymphoblastic leukemia and chronic myeloid leukemia. 1628 63

In metastatic cancer cells, the process of invasion is regulated by several transcription factors that induce changes required for migration and resistance to apoptosis. Slug (SNAI2, Snail2) is involved in epithelial mesenchymal transition in physiological and in pathological contexts. We show here that in embryonic kidney, colon carcinoma, chronic myeloid leukemia-blast crisis, and in neuroblastoma cells, expression of Slug is transcriptionally regulated by c-Myb via Myb binding sites in the 5'-flanking region and in the first intron of the slug gene. In embryonic kidney and neuroblastoma cells, c-Myb induced vimentin, fibronectin, and N-cadherin expression and membrane ruffling via actin polymerization consistent with the acquisition of a mesenchymal-like phenotype. Furthermore, down-regulation of endogenous c-Myb levels in colon carcinoma cells led to increased expression of E-cadherin and reduced levels of vimentin. Some of these changes are predominantly Slug-dependent as Slug silencing via RNA interference (RNAi) reverts the cells to a quasi-parental condition. Changes in gene expression and morphology induced by c-Myb-activated Slug correlated with increased ability to migrate (embryonic kidney) and to invade through a Matrigel membrane (embryonic kidney, colon carcinoma, neuroblastoma). c-Myb-dependent Slug expression was also essential for the homing of chronic myeloid leukemia K562 cells to the bone marrow. In summary, we show here that the proto-oncogene c-Myb controls Slug transcription in tumor cells of different origin. Such a regulatory pathway contributes to the acquisition of invasive properties that are important for the metastatic process.
 ...
PMID:Expression of Slug is regulated by c-Myb and is required for invasion and bone marrow homing of cancer cells of different origin. 2062 60