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Biomedical subjects

N Satake

Publications and source records attributed to N Satake.

At least 37 records · Page 2Linked to original sources

Role of copper accumulation in spontaneous renal carcinogenesis in Long-Evans Cinnamon rats.

Spontaneous renal cell tumors in totals of 223 male and female Long-Evans Cinnamon (LEC) rats of 51-120 weeks old, 157 male F344 rats of 51-120 weeks old, and 14 male Long-Evans Agouti (LEA) rats of 51-70 weeks old were examined histologically. The incidences of renal cell tumors increased with age in male and female LEC rats, but no tumors developed in F344 or LEA rats. Dilated atypical tubules of the kidneys were observed at high incidence in aged LEC rats. Copper staining of LEC rat kidneys showed a positive reaction in proximal tubules of the cortex and the outer stripe of the medulla. The renal copper concentration of LEC rats reached a peak in the period of necrotizing hepatitis with renal tubular necrosis, and was higher than that in F344 rats for up to 106 weeks. In contrast, the renal iron concentration of LEC rats was lower than that in F344 rats except in the period of necrotizing hepatitis. Long-term treatment of LEC rats with D-penicillamine, a copper-chelating agent, inhibited accumulation of copper, but not iron, in the kidneys, and inhibited the development of karyomegaly of proximal tubules and dilated atypical tubules. These results suggest that persistent copper accumulation after toxic necrosis of tubules is the major cause of spontaneous renal carcinogenesis in LEC rats.

Adenoma↗

Proinflammatory or regulatory cytokines released from BALF macrophages of healthy smokers.

BACKGROUND: Chronic smoking influences bronchoalveolar lavage fluid (BALF) cell profiles in healthy subjects, which may alter profiles of inflammatory and regulatory cytokines. OBJECTIVE: We focused on the evaluation of smoking-related changes in the amounts of cytokines released from BALF macrophages. METHODS: We measured the amounts of immunoreactive culture supernatants by using ELISA. RESULTS: The amounts of IL-1 receptor antagonist (IL-1ra) were lower in smokers [n = 10, median 22.1 ng/ml, 25th and 75th percentiles (18.7-39.1)] than in nonsmokers [n = 10, 48.6 (39.2-66.1), p = 0.010]. In smokers, lipopolysaccharide stimulation revealed decreases in the amounts of interleukin-6 (IL-6) [nonsmokers: 2.1 ng/ml (0.68-5.4 vs. smokers: 0.5 (0.03-0.87), p = 0.049] as well as IL-1ra [nonsmokers: 69.2 ng/ml (48.3-83.8) vs. smokers: 27.3 (17.2-56.7), p = 0.028]. A delay in release from intracellular storage was not the cause of the reduced amounts of IL-1ra. In addition, interleukin-1beta (IL-1beta) was positively correlated with IL-6 and granulocyte macrophage colony-stimulating factor in nonsmokers, but not in smokers. Furthermore, the decreases in IL-1ra and interleukin-8 were correlated with the increase in the number of BALF macrophages in smokers, but not in nonsmokers. CONCLUSIONS: Chronic smoking caused changes in the profiles of cytokines released from BALF macrophages in healthy subjects. Decreases in the amounts of regulatory cytokines, but not prominent changes in the amounts of inflammatory ones, were characteristic.

Adult↗

Angiotensin II receptor on BALF macrophages from Japanese patients with active sarcoidosis.

BACKGROUND: Serum angiotensin converting enzyme (ACE) activity and its changes are important markers for disease activity in patients with sarcoidosis. We earlier reported that ACE and its enzymatic product, angiotensin II (A-II), might play a role in maintaining macrophage/T lymphocyte alveolitis by enhancing an accessory function of macrophages in chronic active cases with sarcoidosis. AIM OF THE WORK AND METHODS: We examined whether A-II receptor is present on BALF macrophages by a receptor binding assay using 125I-labeled A-II, and by amplification of A-II receptor gene transcripts using RT-PCR methods and quantification of the amounts of transcripts by HPLC. RESULTS: The receptor binding assay suggested that specific binding of A-II to BALF macrophages was somewhat more prevalent in active sarcoidosis than in controls. A specific band for A-II receptor was detected by RT-PCR. A-II receptor gene expression was standardized as the ratio to beta-actin. An increased ratio was shown in active sarcoidosis (0.70 +/- 0.19; n = 14) compared to inactive cases (0.14 +/- 0.06; n = 5; p = 0.023) and healthy subjects (0.15 +/- 0.09; n = 5, p = 0.029). The ratio correlated positively with the percentage of BALF T lymphocytes (r = 0.60, p = 0.0056), and negatively with BALF macrophages (r = 0.60, p = 0.0055). No difference was detected between nonsmokers and smokers. CONCLUSION: The amounts of A-II receptor gene expression of BALF macrophages correlated with disease activity in patients with pulmonary sarcoidosis.

Adult↗

Biallelic mutations of the Tsc2 gene in chemically induced rat renal cell carcinoma.

A number of cancer genes have been identified by the study of hereditary human cancers and shown to be involved in sporadic genesis of the same tumors. We have identified a germline mutation in the rat homologue of the human tuberous sclerosis (TSC2) predisposing gene in the Eker rat model. In this study, we searched for mutations of the Tsc2 gene in chemically induced non-Eker rat renal cell carcinomas (RCs). N-ethyl-N-hydroxyethylnitrosamine (EHEN)- and diethylnitrosamine (DEN)-induced non-Eker rat primary RCs were subjected to polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis using specific primers covering all exons of the Tsc2 gene (41 coding exons and 1 non-coding exon). We simultaneously searched for mutations in the Vhl gene, a rat homologue of von Hippel-Lindau disease (VHL) gene, as well as the Tsc2 gene. Mutations in the Vhl gene were not detected in any rat RCs (0/8). In contrast, Tsc2 gene mutations were detected at a high frequency in EHEN-induced RCs (2/3) and DEN-induced RCs (3/5) (total 5/8) (p < 0.05). By a direct cloning approach utilizing PCR analysis in 2 applicable cases, we could demonstrate the presence of intragenic somatic mutations in both alleles of the Tsc2 gene. Our results suggest that Tsc2 gene inactivation plays an important role in EHEN- and DEN-induced RCs as well as in Eker rat RCs.

Alleles↗

Amplification of the TCL1 flanking region at 14q32.1 with no TCL1 gene transcription in a patient with peripheral T cell lymphoma.

Cytogenetic and molecular-genetic characteristics in peripheral T cell lymphoma (PTL) have not been well defined, except for those in adult T cell leukemia/lymphoma (ATL/L). Translocations and inversions involving a chromosome band 14q32 were extremely common abnormalities reported in PTL and ATL/L. We studied the involvement of TCL1, a recently isolated gene located in 14q32.1, in tumor tissues from 20 patients with PTL including three with 14q32 translocations by two color fluorescent in situ hybridization (FISH) using two cosmid probes flanking the TCL1 gene. The two cosmid signals were separated in none of them, but much increased in number in one tumor without 14q32 translocation, indicating that the TCL1 genomic region was amplified in this tumor. Reverse transcription-polymerase chain reaction (RT-PCR), however, failed to detect the TCL1 transcript in the tumor. These findings suggest that an oncogene other than TCL1 may be located in 14q32.1, and its amplification may be involved in the neoplastic process of PTL.

Aged↗

Abnormalities of the FHIT transcripts in osteosarcoma and Ewing sarcoma.

In a study of FHIT gene abnormalities by reverse transcription-polymerase chain reaction (RT-PCR) and sequence analysis of the PCR products, we found normal and abnormal PCR products in 11 osteosarcomas, one osteosarcoma cell line and 3 Ewing sarcomas, and a normal PCR product only in 5 osteosarcomas and 8 Ewing sarcomas. Sequence analysis of the abnormal PCR products revealed 7 osteosarcomas lacking exons 4 to 6, 7, 8 or 9, two lacking exons 5 to 7 or 10, and two lacking exons 6 to 8 or 10. In the aberrant transcripts of the 11 osteosarcomas, fusion had occurred in the exon/intron junctions in 2 tumors, between a segment within an exon and a complete exon in 3, and between segments within exons in 6. The 3 Ewing sarcomas had lost exon 4 or 5 to exon 6 or 10, and fusion had occurred in the exon/intron junction in one, and between segments within exons in 2. These findings suggest that both abnormal or variant splicing and other mechanisms such as genomic instabilities in the FHIT locus may have resulted in the expression of aberrant transcripts. One osteosarcoma and one cell line established from this osteosarcoma showed different abnormal FHIT transcripts, indicating that the tumor cells with the initial aberrant transcripts may not have had a selective advantage for proliferation. The FHIT abnormalities did not seem to be correlated with lung metastasis or a poor clinical outcome in our patients with osteosarcoma or Ewing sarcoma.

Acid Anhydride Hydrolases↗

Anaplastic large cell lymphoma associated with Sjögren's syndrome.

We report a case of a 20-year-old Japanese female with recurrent anaplastic large cell lymphoma (ALCL) associated with Sjögren's syndrome (SjS). She was first diagnosed to have ALCL presenting with axillary lymphadenopathy, which within a month underwent spontaneous remission, at the age of 12 years. Eight years later she developed left inguinal lymphadenopathy with clinical overt sicca symptoms associated with elevated serum IgG, interleukin (IL)-1beta and IL-6 levels. Lymph node biopsy was now diagnostic of ALCL characterized by large pleomorphic CD30+ blast cells with the specific chromosomal abnormality, t(2;5)(p23;q35). In contrast to this the salivary gland and renal biopsy revealed infiltration of small lymphocytes, morphologically and cytogenetically distinct from the ALCL cells. Interestingly, SjS symptomatology correlated with disease activity of ALCL and based on an association with elevated IgG and IL-6 levels, suggesting that the concurrence of these two diseases could be more than coincidental. To the best of our knowledge, this is the first reported case of ALCL presenting concurrently with SjS.

Adult↗

Lipocortin I gene expression is higher in blood monocytes than in BAL fluid macrophages in patients with pulmonary sarcoidosis.

BACKGROUND AND AIM OF WORK: Lipocortin I, induced by corticosteroids in vivo is considered to be related to cell activation and differentiation in mononuclear phagocytes, key cells in the process of epithelioid cell granuloma formation in sarcoidosis. Therefore, we focused on the expression of lipocortin I gene in mononuclear phagocytes in patients with sarcoidosis. METHOD: The amounts of transcripts of lipocortin I gene obtained from both BAL fluid macrophages and blood monocytes were measured by RT-PCR and HPLC, and then standardized as the ratio of lipocortin I/beta-actin for comparison. RESULTS: 1. Smoking did not affect the expression of lipocortin I gene in BAL fluid macrophages and monocytes. 2. There were no differences in the amounts of expression in BAL fluid macrophages between patient groups (nonsmokers and smokers), or between patients and healthy subjects. 3. The gene expression in BAL fluid macrophages was higher than that in monocytes in patients with IPF (macrophages 1.23 +/- 0.48, vs monocytes 0.50 +/- 0.38, p < 0.05) and healthy subjects (nonsmokers: 1.66 +/- 1.17, vs 0.34 +/- 0.26, p < 0.05, smoker: 1.98 +/- 0.96, vs 0.34 +/- 0.48, p < 0.05, but sarcoidosis patients showed a higher expression of lipocortin I gene even in monocytes (2.62 +/- 1.87, vs 2.66 +/- 2.21). CONCLUSION: The increase in lipocortin I gene expression in monocytes was a disease-related finding in sarcoidosis.

Annexin A1↗

Minimal residual disease in acute monocytic leukemia patient with trisomy 11 and partial tandem duplication of MLL.

We studied MLL rearrangements in five patients with myeloid hematologic malignancies with trisomy 11. Two had acute monocytic leukemia (AMoL), one had chronic myelomonocytic leukemia, one had refractory anemia, and the other had juvenile chronic myelogenous leukemia. Only one patient, a 15-year-old boy with AMoL and simple trisomy 11, showed rearrangement of MLL. He did not respond to chemotherapy, and successfully underwent bone marrow transplantation, but suffered a relapse 22 months later. Reverse transcription-polymerase chain reaction (RT-PCR) and sequencing analyses of bone marrow cells revealed a tandem duplication of MLL, and his relapse was predictable by sequential RT-PCR studies before it was clinically evident. Of 16 acute myeloid leukemia patients with trisomy 11 and rearrangement of MLL reported, our patient was the youngest in age and the only one with AMoL.

Adolescent↗

Endothelium- and cytochrome P-450-dependent relaxation induced by isoproterenol in rat aortic rings.

In rat aortic rings, the mechanism of endothelium-dependent relaxation induced by isoproterenol is examined. Pretreatment with (+/-)-1-[2,3]-(dihydro-7-methyl-1H-inden-4-yl)oxy]-3-[(1-methyleth yl)amino] -2-butanol (ICI-118,551), a beta 2-adrenoceptor antagonist, or atenolol, a beta 1-adrenoceptor antagonist, partly inhibited the relaxing response to isoproterenol. The relaxing response to isoproterenol in the presence of ICI-118,551 or atenolol was markedly inhibited by removal of endothelium. In the aorta pretreated with ICI-118,551 or atenolol, residual relaxing response to isoproterenol was also inhibited by 2-methyl-1,2-di-3-pyridyl-1-propanone (metyrapone), alpha-naphthoflavone or 8-methoxypsoralen, cytochrome P-450 monoxygenase inhibitors, and methylene blue, but not by indomethacin, a cyclooxygenase inhibitor, 2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1, 4-benzoquinone (AA861), a 5-lipoxygenase inhibitor, NG-nitro-L-arginine (NOARG), a nitric oxide synthase inhibitor, Zn protoporphyrin IX, a heme oxygenase inhibitor, or yohimbine, a alpha 2-adrenoceptor antagonist. In the aorta denuded of endothelium, metyrapone did not affect the residual relaxing response to isoproterenol in the presence of atenolol. These results suggest that the cytochrome P-450 system may be involved in the endothelium-dependent relaxation induced by isoproterenol through beta 1- and beta 2-adrenoceptor activation.

Adrenergic beta-Agonists↗

The involvement of KCa, KATP and KV channels in vasorelaxing responses to acetylcholine in rat aortic rings.

1. In rat aortic rings contracted by phenylephrine, acetylcholine relaxation was partly inhibited by: iberiotoxin, a Ca(2+)-activated K(KCa) channel inhibitor; glyburide, an ATP-dependent K(KATP) channel inhibitor; and 4-aminopyridine, a voltage-dependent K(KV) channel inhibitor, and was almost abolished by the removal of endothelium. 2. NG-nitro-L-arginine (NOARG), a NO synthase inhibitor, markedly reduced acetylcholine relaxation and abolished the inhibitory effects of iberiotoxin and glyburide on the acetylcholine relaxation. The inhibitory effect of 4-aminopyridine on acetylcholine relaxation was partly reduced by NOARG. 3. Methylene blue, a guanylate cyclase inhibitor, markedly inhibited acetylcholine relaxation and also abolished the inhibitory effects of iberiotoxin and glyburide and partly inhibited that of 4-amino-pyridine on acetylcholine relaxation. 4. Metyrapone, a cytochrome P-450-dependent monooxygenase inhibitor, and AA861, a 5-lipoxygenase inhibitor, but not indomethacin, a cyclooxygenase inhibitor, partly inhibited acetylcholine relaxation and reduced the inhibitory effect of 4-aminopyridine on acetylcholine relaxation. 5. These results indicate that, in rat aortic rings, acetylcholine relaxation may be dependent on the activation of KCa, KATP and KV channels. The activations of KCa and KATP channels may also be dependent on NO synthesis and subsequent formation of cGMP. The activation of KV channels may also be dependent on NO synthesis and subsequent activation of guanylate cyclase. In addition, the activation of KV channels may be dependent on the metabolism of arachidonic acid through 5-lipoxygenase and cytochrome P-450-dependent on the monooxygenase pathways.

4-Aminopyridine↗

Potentiation of the relaxing action of isoproterenol by forskolin in rabbit aortic rings: the involvement of beta 2-adrenoceptors.

1. Forskolin, an activator of adenylate cyclase, potentiated the relaxing response to isoproterenol in rabbit aortic rings precontracted by phenylephrine (PE). 2. The potentiating effect of forskolin was inhibited by propranolol, a beta-adrenoceptor inhibitor, but not by methylene blue, a guanylate cyclase inhibitor. 3. The relaxing response to terbutaline, a beta 2-adrenoceptor agonist, but not lower concentrations of dobutamine, a beta 1-adrenoceptor agonist, also was potentiated by forskolin. Forskolin, however, potentiated the relaxing response to high concentrations of dobutamine, which activates both beta 1- and beta 2-adrenoceptors. 4. Yohimbine, an alpha 2-adrenoceptor inhibitor, glyburide, an ATP-sensitive K+ channel inhibitor, iberiotoxin, a Ca(2+)-activated K+ channel inhibitor, or endothelium-removal failed to affect the potentiating effect of forskolin. 5. Dibutyryl cyclic AMP (cAmp) also potentiated the relaxing response to terbutaline. 6. These results suggest that in rabbit aortic rings forskolin causes the apparent potentiation of isoproterenol-induced relaxation by mainly affecting the relaxing response due to the activation of beta 2-adrenoceptors by the forskolin-induced increase in the level of cAMP.

Adenylyl Cyclases↗

Minimal residual disease with TEL-AML1 fusion transcript in childhood acute lymphoblastic leukaemia with t(12;21).

We analysed the TEL-AML1 transcript using reverse transcription-polymerase chain reaction (RT-PCR) in order to detect minimal residual disease (MRD) in seven children with t(12;21)-associated B-lineage ALL. Leukaemic cells with the TEL-AML1 transcript appear to be very sensitive to chemotherapy, and may be eradicated in most patients if adequate chemotherapy is given. However, a small number of patients with t(12;21) ALL may relapse under the currently used chemotherapy, and we believe that RT-PCR for detecting MRD with the transcript is a suitable tool for monitoring the efficacy of chemotherapy or impending relapse in these patients. We analysed the TEL-AML1 transcript using reverse transcription-polymerase chain reaction (RT-PCR) in order to detect minimal residual disease (MRD) in seven children with t(12;21)-associated B-lineage ALL. Two sets of primers, TEL exon 5 and AML1 exon 3 or 4, detected two types of transcript in four patients and two other types in two other patients. The two different translocation breakpoints in the AML1 gene with or without splicing out of AML1 exon 3 seemed to result in these four types of transcript in leukaemia samples.

Child↗

Impaired relaxing response to isoprenaline in isolated thoracic aorta of nephrotic rats: decrease in release of EDRF from endothelial cells.

Isoprenaline-induced relaxation was investigated in aortas from control and daunomycin-induced nephrotic rats. In the endothelium-intact aortas precontracted with phenylephrine, the isoprenaline-induced relaxation and cyclic adenosine monophosphate (AMP) accumulation were significantly less in nephrotic rats than in control animals. Removal of the endothelium, pretreatment with methylene blue (MB), a guanylate cyclase inhibitor, or NW-nitro-L-arginine methyl ester (L-NAME), a nitric oxide (NO) synthase inhibitor, markedly reduced the relaxation induced by isoprenaline in nephrotic and control animals. The increase in cyclic AMP content induced by isoprenaline also was inhibited by these treatments. In addition, the difference in the isoprenaline-induced relaxation and cyclic AMP accumulation between nephrotic and control preparations was abolished by these treatments. The tissue cyclic guanosine monophosphate (GMP) level was not affected by isoprenaline. In the presence of zaprinast (Zap), a cyclic GMP phosphodiesterase inhibitor, the cyclic GMP level in the endothelium-intact tissues was significantly lower in nephrotic rats than in control animals. Removal of endothelium or pretreatment with MB or L-NAME markedly reduced cyclic GMP content in nephrotic and control animals. In the endothelium-denuded tissues, the isoprenaline-induced relaxation and cyclic AMP accumulation were markedly potentiated by a low concentration of nitroprusside (NP). In the endothelium-intact aortas precontracted with phenylephrine, relaxations induced by dobutamine, salbutamol, and forskolin in nephrotic rats were not significantly different from those in control animals. In the endothelium-intact aortas precontracted with KCl, the isoprenaline-induced relaxation also was significantly less in nephrotic rats than in control animals. Pretreatment with prazosin, but not yohimbine, abolished this difference. These results indicate that nephrosis decreases the relaxing response of the endothelium-intact aortas to isoprenaline. In addition, these results suggest that the endothelium-derived relaxing factor (EDRF) released from the endothelial cells markedly enhances isoprenaline-induced increase in the tissue level of cyclic AMP. The decreased relaxing response to isoprenaline in nephrotic rats may be caused by the decrease in the endothelial-dependent cyclic GMP release caused by alpha 1-adrenoceptor activation by isoprenaline.

Animals↗

The contractile mechanism of sodium metavanadate in isolated rat aortae.

The mechanism of contractile effect of vanadate was investigated in rat aortae. Sodium metavanadate (NaVO3; 10(-5)-3 x 10(-3) M) induced contractile responses in a concentration-dependent manner. Removal of endothelium did not affect the response to NaVO3. The response to NaVO3 was inhibited by nifedipine, a voltage-operated Ca2+ channel (VOC) inhibitor; NCDC, a phospholipase C inhibitor; and H-7, a protein kinase C inhibitor, but not by prazosin, an alpha1-adrenoceptor antagonist; methysergide, a serotonin-receptor antagonist; tripelennamine, a histamine-receptor antagonist; glibenclamide, an adenosine triphosphate (ATP)-dependent K+-channel inhibitor; or iberiotoxin, a large-conductance Ca2+-activated K+-channel inhibitor. In addition, genistein or tyrphostin A48, tyrosine kinase inhibitors, did not affect the contraction induced by NaVO3. Mg2+ removal or antimycin A, a Ca2+-ATPase inhibitor, did not cause any contraction. Ouabain, a Na+, K+-ATPase inhibitor, or K+-free medium caused the contraction of the aortae. The maximal contraction induced by NaVO3 plus ouabain was similar to that induced by NaVO3 alone. In addition, the response to NaVO3 was inhibited by AA861, a 5-lipoxygenase inhibitor, and RHC-80267, a diacylglycerol (DAG) lipase inhibitor. In the presence of AA861, either H-7 or nifedipine further inhibited the residual response to NaVO3. In the presence of NCDC, however, AA861 failed further to affect the residual response to NaVO3. In rat aortae, NaVO3 increased the levels of inositol monophosphate (IP) and prostaglandin F2alpha (PGF2alpha). AA861 and NCDC inhibited the IP increase. In addition, NCDC inhibited the PGF2alpha increase. These results suggest that the response to NaVO3 in rat aortae may be mainly the result of the increased phosphoinositide metabolism.

Animals↗

Detection of the Der (21)t(12;21) chromosome forming the TEL-AML1 fusion gene in childhood acute lymphoblastic leukemia.

The t(12;21) (p13;q22) is observed in approximately 20-25% of childhood B-lineage acute lymphoblastic leukemia (ALL) cases in both Asian and Caucasian populations. This translocation results in the fusion of TEL, a recently described ETS-like gene on 12p13, and AML1, which was shown to be involved in the formation of fusion genes with ETO and EVI1 in myeloid leukemias. Fluorescence in situ hybridization (FISH) and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis are useful in detecting this translocation which is not readily identified with routine cytogenetic techniques. The t(12;21) is associated with a distinct subgroup of patients characterized by an age between 1 and 10 years, an early B immunophenotype, and a good prognosis. A high incidence of the deletion of non-translocated TEL is another characteristic of leukemic cells with this translocation. TEL-AML1 hybrid protein thought to be critical in leukemogenesis possesses the HLH domain of TEL fused to almost the entire AML1 protein, although the detailed mechanisms of leukemogenesis remain obscure. RT-PCR combined with FISH analysis of posttreatment samples appears to be useful in detecting early relapse or minimal residual disease and thus, is expected to optimize the treatment strategy for patients with t(12;21).

Biomarkers, Tumor↗

EWS-ERG fusion transcript produced by chromosomal insertion in a Ewing sarcoma.

The EWS gene is fused in Ewing sarcoma-like tumors by a chromosomal translocation to one of the four ETS-family genes: FLI1, ERG, ETV1, and E1AF. The orientation of EWS and FLI1 on chromosomes 22 and 11, respectively, is 5' centromeric and 3' telomeric, whereas that of ERG on chromosome 21 is the reverse. Although 10% of Ewing-family tumors express the EWS-ERG fusion transcript, there have been no reports on tumors with t(21;22)(q22;q12) identified by banding cytogenetics. We found the karyotype 50, XY, +8, +8, +12, +mar in all metaphase cells from a tumor. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis performed on the tumor and direct sequencing of the products identified the EWS-ERG fusion transcript. Subsequent two-color fluorescence in situ hybridization (FISH) analysis with EWS and ERG clones showed the fused signals on the der(21) chromosome, but no ERG signals on the chromosome 22 homologs. Thus, our RT-PCR and FISH analyses indicated that the chromosome 22 fragment containing the 5' portion of EWS had been inverted and inserted into chromosome 21 and had fused to the 3' portion of ERG. This subtle chromosome aberration could not be identified by routine cytogenetics. A chromosomal inversion/insertion has also been described in acute leukemia with the MLL-AF10 fusion gene, and this may be a common pathway for producing fusion of reverse-oriented genes in leukemias and solid tumors.

Bone Neoplasms↗