Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0035412 (rhabdomyosarcoma)
 6,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Insulin-like growth factor-II (IGF-II) is an autocrine growth and motility factor for human rhabdomyosarcoma. It interacts with three different receptors: the IGF-I, the IGF-II, and the insulin receptor. A specific function of the IGF-II receptor in mediating IGF-II responses has not been defined. In this report we investigate the mechanism of IGF-II-mediated motility in rhabdomyosarcoma cells. We demonstrate that IGF-II and [Leu27]IGF-II, an analog selective for the IGF-II receptor, stimulate motility at concentrations in which they interact only with their own receptor. An antibody that blocks the IGF-I receptor does not inhibit either peptide activity, while an antibody specific for the IGF-II receptor suppresses the IGF-II-induced motility. This antibody does not interfere with rhabdomyosarcoma cell proliferation. We conclude that in rhabdomyosarcoma cells IGF-II stimulates two different responses mediated by distinct receptors: 1) a mitogenic response through the type I receptor and 2) a motility response through the type II receptor.
 ...
PMID:The insulin-like growth factor II (IGF-II)/mannose 6-phosphate receptor mediates IGF-II-induced motility in human rhabdomyosarcoma cells. 131 46

Insulin-like growth factor II (IGF-II) belongs to the insulin family of peptides and acts as a growth factor in many fetal tissues and tumors. The gene expression of IGF-II is initiated at three different promoters which gives rise to multiple transcripts. In a human rhabdomyosarcoma cell line IN 157 IGF-II mRNAs of 6.0-kb, 4.8-kb, and 4.2-kb are present. Fractionation of cellular extracts on sucrose gradients and Northern blot analysis showed that only the 4.8-kb mRNA was associated with polysomes, whereas the other transcripts cosedimented with monosomal particles. This suggests that only the 4.8-kb mRNA is translated to IGF-II. The cell line secretes two forms of immunoreactive and bioactive IGF-II to the medium of molecular size 10 kd and 7.5 kd which may be involved in autocrine control of cell growth. IGF-II binds to two receptors on the surface of many cell types: the IGF-I receptor and the mannose-6-phosphate (Man-6-P)/IGF-II receptor. There is consensus that the cellular effects of IGF-II are mediated by the IGF-I receptor via activation of its intrinsic tyrosine kinase. The Man-6-P/IGF-II receptor is involved in endocytosis of lysosomal enzymes and IGF-II. In selected cell types, however, Man-6-P induces cellular responses. We have studied rat brain neuronal precursor cells where Man-6-P acted as a mitogen suggesting that phosphomannosylated proteins may act as growth factors via the Man-6-P/IGF-II receptor. In conclusion, the gene expression and mechanism of action of IGF-II is very complex suggesting that its biological actions can be regulated at different levels including the transcription, translation, posttranslational processing, receptor binding and intracellular signalling.
 ...
PMID:Insulin-like growth factor II: complexity of biosynthesis and receptor binding. 172 20

Multiple transforming growth factors (TGFs) capable of conferring the neoplastic phenotype on NRK-49F cells without the addition of any other exogenous growth factor in the soft agar assay, were purified from two human solid malignant neoplasms: a squamous lung carcinoma and a pectoral rhabdomyosarcoma. In both tumors, low-molecular-weight transforming activities (4000-6000) that were not potentiated by epidermal growth factor (EGF), competed for binding to the EGF receptor, possessed mitogenic activity on NRK fibroblasts arrested in serum-deprived medium, and did not show inhibitory effects on DNA synthesis induced by EGF and insulin in NRK cells. Other TGFs with molecular weights 9000 to 48,000, were also found in the malignant tissues examined; these TGFs, were not potentiated by EGF, did not compete for binding to the EGF receptor, were not mitogenic for NRK cells, and acted as potent inhibitors of DNA synthesis induced by EGF and insulin in NRK cells. These results demonstrate that growth-promoting activities, and modulating agents that can act as either enhancers or inhibitors of cell proliferation, are present in neoplastic tissues of different embryologic origin and histologic type.
 ...
PMID:Alpha-transforming growth factorlike activities and bifunctional regulators of cell growth in human malignant neoplasms. 220 63

Pancreatic tumors are rare in children. Over a 20-year period we have treated 13 children with pancreatic neoplasms. There were eight boys and five girls (age range, 4 months to 12 years). Seven tumors were benign, including five insulinomas, and two cystadenomas. Six lesions were malignant (rhabdomyosarcoma, 2; pancreatic carcinoma, 4). Children with insulinoma presented with hypoglycemia and irrational behavior. Three had abnormal insulin:glucose ratios ( greater than 1.0). The tumor was detected by computed tomography scan in three cases, at the time of surgery in one, and with intraoperative ultrasound in one. Surgical treatment included tumor enucleation in four cases and 80% pancreatectomy in one. Mucinous cystadenomas were observed in two patients, ages 4 months and 10 months. Tha latter infant underwent cyst excision alone, resulting in malignant recurrence at 18 months of age and death. The 4-month-old child had a distal pancreatectomy and is alive at 6 years. Two of the four children with pancreatic cancer had unresectable tumors at diagnosis, and were treated by biopsy (ductal adenocarcinoma), irradiation, and chemotherapy. Length of survival was 6 months and 9 months. Two others (ages 4 and 12 years) underwent 85% distal pancreatic resection for pancreatoblastoma and a pancreatoduodenectomy for papillary carcinoma, respectively. The latter is alive and tumor-free at 20 years of follow-up. The former underwent hepatic lobectomy for a 3.0 x 3.0 cm solitary liver metastases and is alive at 6 years with no evidence of disease. One child with rhabdomyosarcoma died of progressive disease, the other is alive with residual disease despite resection and chemotherapy. Most insulinomas can be treated by enucleation.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Pancreatic tumors in childhood: analysis of 13 cases. 226 58

The ability of tumor cells to develop simultaneous resistance to structurally different cytotoxic drugs constitutes a major problem in cancer chemotherapy. We previously described that a nitrosourea, chlorozotocin (CZT), increased in vivo the pulmonary metastatic dissemination of a rat rhabdomyosarcoma and enhanced in vitro the cloning efficiency (CE) of the same tumor cell line. The selection procedure for chlorozotocin-selected cell lines (R1 to R9 lines), by in vitro CZT-treatment and cloning assay, indicated that 2.5% of the parental cell line was a CZT-resistant subpopulation. This subset acquired, in the course of the selection steps in semi solid medium, a multidrug-resistant phenotype. In a stem cell assay, the resistance of the R9 line was increased 10-fold for adriamycin (ADR) and up to 2 fold for cisplatinum. In comparison, C8 control line sensitivity to ADR did not change significantly. This resistance did not affect the non clonogenic population, as shown in a monolayer proliferation assay. Re-exposure of R (R1-R9) lines to CZT or initial CZT contact with C lines transiently but consistently increased the CE; however, clonogenicity remained stable, and this was also observed when deticene, another alkylating drug, was used instead of CZT. Moreover, the CZT-selected R9 line easily proliferated in serum-free medium in the presence of transferrin and insulin, whereas serum was necessary to maintain the growth of the parental cell line or C lines. Finally, we show that in vitro selection of variants, by both resistance to CZT and cloning, led to the isolation of a multi-drug resistant subpopulation, serum independent for its proliferation - two properties associated with progressive malignancy.
 ...
PMID:Chlorozotocin-induced selection of autocrine and multidrug resistant variants from a rat rhabdomyosarcoma. 296 63

p57KIP2 is a potent tight-binding inhibitor of several G1 cyclin/Cdk complexes, and is a negative regulator of cell proliferation. The gene encoding human p57KIP is located on chromosome 11p15.5 (ref. 2), a region implicated in both sporadic cancers and Beckwith-Wiedemann syndrome, a familial cancer syndrome, marking it a tumour suppressor candidate. Several types of childhood tumours including Wilm's tumour, adrenocortical carcinoma and rhabdomyosarcoma display a specific loss of maternal 11p15 alleles, suggesting that genomic imprinting plays an important part. Genetic analysis of the Beckwith-Wiedemann syndrome has indicated maternal carriers as well as suggested a role in genomic imprinting. Here, as a first step towards elucidating the genesis of human cancers in this region, we showed that a mouse homologue of p57KIP2 is genomically imprinted. The paternally inherited allele is transcriptionally repressed and methylated. This murine gene maps to the distal region of chromosome 7, within a cluster of imprinted genes, including insulin-2, insulin-like growth factor-2, H19 and Mash2 (refs 14-18).
 ...
PMID:Genomic imprinting of p57KIP2, a cyclin-dependent kinase inhibitor, in mouse. 755 Mar 51

In 1979, 2 species of pond frogs (Rana nigromaculata and Rana plancyi plancyi) were imported from China, and hybrids were made between these and Japanese, Korean, and Taiwanese pond frogs (R. nigromaculata, Rana plancyi fukienensis and Rana brevipoda) that had been kept for a number of years in the Laboratory for Amphibian Biology of Hiroshima University. From 1982, development of tumors, especially in the peritoneal cavity, was noticed frequently in the hybrids and also later, although rarely, in the Japanese pond frogs. Such tumors had never previously been observed among pond frogs in the laboratory. Histological and immunohistochemical studies identified the i.p. tumors to be pancreatic carcinomas with occasional production of insulin and/or somatostatin. Ultrastructural investigation revealed both endocrine and exocrine secretion granules together with C-type retrovirus particles in the carcinoma cells. Other tumors included a retroperitoneal rhabdomyosarcoma, liver adenomas, and an unclassifiable mesenchymal tumor of the foot pad.
 ...
PMID:Frequent development of pancreatic carcinomas in the Rana nigromaculata group. 764 Nov 93

Insulin-like growth factors are abnormally expressed in some pediatric solid tumors. In addition, tumors that do not show significant alterations in pattern of expression are responsive to and may be dependent upon insulin-like growth factors for proliferation. These can be produced by the tumor cells (autocrine), surrounding stromal cells (paracrine), or at a distance (endocrine). Insulin-like growth factor-II plays a role in Wilm's tumor, neuroblastoma, and rhabdomyosarcoma, either as a proliferation factor, a motility factor, or both. Insulin-like growth factor-I may regulate osteosarcoma and the Ewing's family of tumors (primitive neuroectodermal tumors). Understanding the biology of these growth factors and their receptors can lead to new therapeutic approaches.
 ...
PMID:Diverse roles of insulin-like growth factors in pediatric solid tumors. 805 16

The expression of the insulin-like growth factors (IGFs) and their receptors has been linked to cellular proliferation and tumorigenicity in a number of model systems. Since rhabdomyosarcoma cells express IGF-I receptors, an autocrine or paracrine loop involving this receptor and its ligands could be responsible in part for the growth characteristics of this tumor. To assess directly the role of the IGF-I receptor in rhabdomyosarcoma cell growth and tumorigenicity, a human alveolar rhabdomyosarcoma cell line with high IGF-I receptor expression was transfected with an amplifiable IGF-I receptor antisense expression vector. Four unique, transfected clones were analyzed and found to have reduced IGF-I receptor expression relative to the parental line. Integration of the antisense sequence was demonstrated by Southern blot analysis, and expression of antisense message in these clones was shown by S1 nuclease protection assay. Reduced IGF-I receptor surface expression in the transfectants was shown by decreased immunofluorescence with an IGF-I receptor monoclonal antibody and by decreased IGF-I binding as measured by Scatchard analysis. These clones had markedly reduced growth rates in vitro, impaired colony formation in soft agar, and failed to form tumors in immunodeficient mice when compared with vector-transfected clones. These results demonstrate that reduction of IGF-I receptor expression can inhibit both the in vitro and in vivo growth of a human rhabdomyosarcoma cell line and suggest a role for the IGF-I receptor in mediating neoplastic growth in this mesenchymally derived tumor.
 ...
PMID:Antisense-mediated reduction in insulin-like growth factor-I receptor expression suppresses the malignant phenotype of a human alveolar rhabdomyosarcoma. 808 65

The polymerase chain reaction was used to amplify protein tyrosine phosphatase (PTPase)-related cDNA from a template of total RNA isolated from human skeletal muscle. A novel PTPase, which we term PTP-PEST, was detected by this method. The polymerase chain reaction fragment was used to screen two different HeLa cell libraries to obtain full length cDNA clones. The cDNA predicts a protein of 510 amino acids, approximately 60 kDa, that does not contain an obvious signal sequence or transmembrane segment suggesting it is a nonreceptor type enzyme. The PTPase domain is located in the N-terminal portion of the molecule and displays approximately 35% identity to other members of this family of enzymes. The C-terminal segment is rich in Pro, Glu, Asp, Ser, and Thr residues, possessing features of PEST motifs which have previously been identified in proteins with very short intracellular half-lives. The protein was expressed in Escherichia coli as a fusion product with glutathione S-transferase. Intrinsic activity was demonstrated in vitro against a variety of phosphotyrosine-containing substrates including BIRK, the autophosphorylated cytoplasmic kinase domain of the insulin receptor beta subunit. It did not dephosphorylate phosphoseryl-phosphorylase a. PTP-PEST mRNA is broadly distributed in a variety of cell lines. Stimulation of human rhabdomyosarcoma A204 cells, a transformed muscle line, with insulin led to an approximately 4-fold induction of PTP-PEST mRNA within 36 h.
 ...
PMID:Cloning and expression of PTP-PEST. A novel, human, nontransmembrane protein tyrosine phosphatase. 834 45


1 2 3 4 5 Next >>