Involvement of PLAGL2 in activation of iron deficient- and hypoxia-induced gene expression in mouse cell lines

We searched iron-deficient inducible cDNA, using subtraction cloning and mRNA from desferrioxamine-treated mouse macrophage Raw264.7 cells. We identified a pleomorphic adenoma gene like 2 (PLAGL2), one of PLAG superfamily proteins exhibiting antiproliferative properties on tumor cells. Mouse PLAGL2 consists of 496 amino acids with seven C2H2 zinc-fingers. PLAGL2 mRNA was induced in RAW264.7 cells, mouse erythroleukemia cells and Balb/c 3T3 cells when they were treated with desferrioxamine. Hypoxia also increased PLAGL2 mRNA. Expression of PLAGL2 in COS-7 cells led to nuclear localization. PLAGL2 had potential binding ability to GC-rich oligonucleotide and activated transcription of a gene with the binding sequence in transient reporter assay, a finding consistent with a case seen in a PLAGL2 homolog, ZAC-1. Transient co-transfection of PLAGL2 or ZAC1 cDNA and a reporter containing a lactate dehydrogenase A (LDHA) promoter carrying the hypoxia inducible factor-1 responsive element led to an increase in the basal transcription in Balb/c 3T3 and HepG2 cells. Activation in transcription from the LDHA promoter increased by desferrioxamine treatment or hypoxia was further enhanced when PLAGL2 was expressed. We propose that PLAGL2 is involved in the cell cycle arrest and apoptosis of tumor cells by regulating iron depletion- or hypoxia-inducible gene expression.

[The clinical significance of M proteins]

M protein refers to a monoclonal gammaglobulin that is produced by the monoclonal proliferation of plasma cells. More than 50% of M proteinemia is classified as MGUS, but lymphoproliferative disorders such as multiple myeloma and Waldenström's macroglobulinemia may also develop from MGUS. Therefore, in patients with MGUS it is very important to observe the clinical course. MGUS develops in many disorders including chronic infection, autoimmune disease, various type of neoplasm, neurological disease and skin disease. In general, no treatment is required for MGUS and smoldering type myeloma in which the clinical course and laboratory data are stable. However, in progressive myeloma or cases of plasmacytoma chemotherapy, radiation and/or surgery are indicated. Some factors are known to predict the prognosis of multiple myeloma, and poly(A) polymerase may be a useful indicator for predicting the prognosis of multiple myeloma.

Pleiotropic functions and tissue-specific expression of erythropoietin

Erythropoietin (EPO) is produced in the brain, uterus, and oviduct. Brain EPO plays a neuroprotective role, and uterine EPO is likely involved in estrogen-dependent angiogenesis. Hypoxic induction of brain EPO markedly differs from that in the kidney. EPO in the uterus and oviduct is estrogen inducible.

Clinical significance of serum pulmonary surfactant proteins a and d for the early detection of radiation pneumonitis

PURPOSE

Radiation pneumonitis (RP) is one of the most serious complications for patients who receive thoracic irradiation. To avoid this, early diagnosis of radiation pneumonitis is extremely important. The purpose of the present study is to investigate whether serum pulmonary surfactant proteins A and D (SP-A and SP-D, respectively) could be useful markers for RP.

METHODS AND MATERIALS

Eighty-six patients (lung cancer: 42 [primary: 39, metastatic: 3], breast cancer: 23, esophageal cancer: 21) who underwent radiation therapy were prospectively studied. Radiation doses ranged from 30-76 Gy (median, 58 Gy). Serum SP-A and SP-D levels were evaluated sequentially by a sandwich enzyme-linked immunosorbent assay (ELISA) method before, during, and throughout the follow-up period until the development of symptomatic RP or until one year after completion of radiotherapy. Specificity of the ELISA results was confirmed by Western blot analysis. Patients symptomatic for RP were graded according to the Common Toxicity Criteria.

RESULTS

RP occurred in 19 patients. Serum SP-D levels of patients with RP were sequentially higher than those in patients without RP. In the monitoring, serum SP-D levels at 50-60 Gy showed greater sensitivity and positive predictive values for RP detection (74% and 68%, respectively) than SP-A (26% and 21%, respectively). Western blot analysis showed that the development of RP was due to overproduction, but not proteolysis of surfactant proteins.

CONCLUSION

We confirm that serum SP-A and SP-D monitoring is a practical and useful diagnostic method for the early detection of RP.

Prognostic significance of lymph node involvement in middle and distal bile duct cancer

BACKGROUND

Although lymph node involvement is considered an important prognostic factor, a detailed analysis has not been conducted in middle (Bm) and distal (Bi) bile duct cancer.

METHODS

The histopathology of resections taken from 59 patients with Bm and Bi disease (Bm, 33 patients; Bi, 26 patients) was examined. The prevalence of lymph node involvement and its relationship to recurrence and prognosis were investigated. Survival rates were investigated according to the number of metastatic lymph nodes found, the TNM nodal stages, and the nodal stage classifications of The General Rules of the Japanese Society of Biliary Surgery.

RESULTS

The frequency of nodal involvement in Bm and Bi was 45.5% and 30.8%, respectively. A significant correlation existed between a patient's prognosis and his TNM nodal stage, Japanese Society of Biliary Surgery nodal stage, and the number of metastatic lymph nodes found (P <.0001, respectively). Among 8 sites of postoperative recurrence, metastasis occurred most frequently in the liver (16/23). Patients with nodal involvement had a significantly higher rate of liver metastasis (10/23) than those without it (6/36) (P =.024).

CONCLUSIONS

The number of metastatic lymph nodes found in patients with Bm or Bi cancer, and the nodal stage of their nodes, are significant prognostic indicators. Patients with nodal involvement are at high risk for liver metastasis in Bm and Bi disease.

Familial amyotrophic lateral sclerosis and parkinsonism-dementia complex of the Kii Peninsula of Japan: clinical and neuropathological study and tau analysis

We report the first case of neuropathologically verified parkinsonism-dementia complex of the Kii peninsula, together with the patient's brother, who had amyotrophic lateral sclerosis. The propositus woman developed parkinsonism and dementia at 63 years of age and died at 70 without displaying clinical features of amyotrophic lateral sclerosis. The brain exhibited marked atrophy of the frontal and temporal lobes. Microscopically, there were many neurofibrillary tangles in the central nervous system, most markedly in the mesial temporal lobe and deep nuclei, as well as changes of amyotrophic lateral sclerosis but no senile plaques or Lewy bodies. Neurofibrillary tangles exhibited twisted tubule structures on electon microscopic examination, and an analysis of insoluble tau protein extracted from the fresh brain revealed a 60-, 64-, 68-kD triplet. The tau gene exhibited no mutations. Her brother developed progressive bulbar palsy-type amyotrophic lateral sclerosis at 45 years of age and died at 49 without presenting with dementia or parkinsonism. Neuropathological examination revealed not only pathologic features of amyotrophic lateral sclerosis but also a moderate number of neurofibrillary tangles in the temporal cortex and deep nuclei. The siblings were neuropathologically similar despite their different clinical manifestations. These findings suggest that amyotrophic lateral sclerosis and parkinsonism-dementia complex of this family may be phenotypic variants of a tauopathy caused by genetic abnormalities.

Pilot study of local radiotherapy for portal vein tumor thrombus in patients with unresectable hepatocellular carcinoma

BACKGROUND

Patients suffering from hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) generally have a poor prognosis. We therefore conducted a prospective pilot trial of combined transcatheter arterial chemoembolization (TACE) and local radiotherapy (RT) for PVTT in unresectable HCC. The aim of the study was to investigate the efficacy and toxicity of this preliminary trial regime and to explore RT guidelines for cirrhosis.

METHODS

Eight patients with unresectable HCC accompanied by first branch PVTT were entered into the study from February 1998 to December 1999. TACE was performed using Lipiodol, epirubicin hydrochloride and mytomycin followed by gelatin sponge cubes. RT was started 10-14 days following TACE. A total delivered dose of 60 Gy was given as daily 2 Gy fractions, with the clinical target volume defined as PVTT only. We observed a relationship between deterioration of liver function and the percent volume of the total liver receiving a dose exceeding 30 Gy (V30).

RESULTS

An objective response was observed in three of the eight patients. However, on follow-up angiograms the protrusion of PVTT into the main portal trunk was decreased in all cases. Deterioration of liver function was observed in all patients with V30 >40%.

CONCLUSION

It is possible that this combined therapy prevents PVTT from spreading to the main trunk and that indicates a further benefit of TACE. Our results indicate that V30 constitutes a predictive test for the development of liver failure. More detailed evaluations of liver function and determination of the safe irradiation volume are necessary.

Prenatal ionizing radiation-induced apoptosis of the developing murine brain with special references to the expression of some proteins

Apoptosis induced by ionizing irradiation of the developing mouse brain was investigated by using histology, analysis of DNA fragmentation on agarose gel and electron microscopy. A TUNEL-labeled index (L.I.) was calculated from the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) assay in 4 specific regions, cortical plate, intermediate zone, subependymal zone, and subependymal germinal matrix. The kinetics of apoptosis associated protein was examined by western blotting and immunofluorescence. C57BL/6J mice pregnant on embryonic day 14 (E14) were exposed to a single dose of 1.5-Gy irradiation. Irradiated fetal brains at E15 and E17 showed extensive apoptosis with morphological characteristics. In all 4 regions, L.I. was greater in irradiated brains than in control brains at E15 and E17. Most of TUNEL-labeled cells expressed a mature neuronal marker (NeuN) and Bax protein, which is up-regulated in irradiation-induced apoptosis. Ionizing radiation moderately enhanced expression of Bax, Bcl-xL, and Cpp32 proteins. Postnatal irradiated mice showed microencephaly as compared to age-matched mice and the weight of whole body including brain decreased moderately.

Expression of human brain carboxypeptidase B, a possible cleaving enzyme for beta-amyloid precursor protein, in peripheral fluids

Human brain carboxypeptidase B (HBCPB) is a novel brain protease that processes native brain beta-amyloid precursor protein (APP) in vitro. Immunoblot analysis of human serum and cerebrospinal fluid (CSF) using anti C14-module antibody, which recognizes the C-terminal peptide unique to HBCPB, detected the 30 and 40 kDa immunoreactive bands. Analysis of HBCPB prepared from both serum and CSF demonstrated proteolytic activities for brain APP. Protease inhibitor spectrum analysis also supports that these bands correspond to the mature form and and prepro form of HBCPB, respectively. As is the case in brain parenchyma, the prepro-form is dominant in CSF. In serum, however, the majority of HBCPB exists in the mature form, possibly due to an abundant trypsin-like proteolytic activity in serum. HBCPB expressed in serum and CSF, therefore, may have a significance as a peripheral marker of the brain protease, which participates in APP processing in human brain.

Inhibition of erythropoietin signalling destroys xenografts of ovarian and uterine cancers in nude mice

We have recently shown that malignant tumours from the ovary and uterus expressed erythropoietin (Epo) and its receptor (EpoR), and that deprivation of Epo signal in tumour blocks induced death of malignant cells and capillary endothelial cells in vitro (Yasuda et al, submitted). These in vitro results prompted us to examine the effect of Epo-signal withdrawal on tumours in vivo. RT-PCR analysis demonstrated the expression of mRNAs for Epo and EpoR in the transplants of uterine and ovarian tumours in nude mice. Then we injected locally anti-Epo antibody or soluble form of EpoR into the transplants. At 12 h, 1, 7 or 14 days after the injection, all transplants were resected and examined macro- and microscopically. Tumour size was reduced in Epo signal-deprived transplants. Immunohistochemical examinations revealed destruction of Epo-responding malignant and capillary endothelial cells through apoptotic death. The degree of tumour regression correlated well with the dose and frequency of the injections. Control xenografts with saline injection or needle insertion showed well-developed tumour masses. This Epo response pathway will have profound implications for our understanding of the development and progression of malignant tumours and for the use of Epo-signal deprivation as an effective therapy.

A novelCLCN1 mutation: P480T in a Japanese family with Thomsen's myotonia congenita

At least 50 disease-causing mutations in the skeletal muscle voltage-gated chloride channel gene (CLCN1), almost all of which originate from Caucasian families, have been identified. We investigated a Japanese family with Thomsen's myotonia congenita that included 16 affected individuals (8 men and 8 women) through five generations. Polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) screening of 11 members showed an aberrant conformer in exon 13 of CLCN1 complementary DNA (cDNA) in 8 affected and 1 unaffected members. By sequence analysis, we identified a C-to-A transition at nucleotide position 1438, resulting in a substitution of proline for threonine at amino acid position 480 (P480T), the same position of the original mutation (P480L) in Thomsen's disease. The P480T mutation was novel and absent in 100 normal controls. Seven of the 8 affected individuals were heterozygous; another, from affected parents, was homozygous. Clinically, myotonia in the homozygous patient was more severe than that in heterozygous patients, probably due to the gene dosage effect. On a long-train nerve-stimulation test at a rate of 3 Hz, M-wave responses in the homozygous patient showed marked decrement followed by recovery. In contrast, the heterozygous patients showed just a slight decrement or no changes, and none of 2 patients with myotonic muscular dystrophy or 2 normal controls revealed any decrement. Thus, the long-train nerve-stimulation test at a low stimulus frequency may be a useful tool to assess the disease-severity/genotype relationship in myotonia congenita.

In vivo gene electroporation in skeletal muscle with special reference to the duration of gene expression

To determine the limits of the duration of in vivo transferred foreign gene expression, we conducted electroporation (EP), a powerful non-viral means of gene transfer for living animals, into skeletal muscle of rats and mice with a luciferase, GFP or erythropoietin (EPO)-encoding reporter plasmid. The luciferase reporter plasmid was used for optimization of EP conditions, while GFP and EPO plasmids were used for monitoring the duration of gene expression. In the rat, increased hematocrit levels were maintained for at least 9 weeks with approximately a 3-fold increase in plasma EPO protein concentration at 4 weeks post-transfection. In the mouse, the GFP plasmid transfer confirmed that the reporter gene expression lasted as long as 3 months post-transfection. By introducing the EPO gene in vivo in the mouse, increased hematocrit levels revealed that duration of reporter gene expression was at least 14.5 months after in vivo gene EP into skeletal muscle. These results implicate an excellent potential of in vivo gene EP, applicable to both experimental and therapeutic purposes.

Growth and secretion of erythropoietin of Chinese hamster ovary cells coexpressing epidermal growth factor receptor and erythropoietin genes: Design of cells for cell culture matrix

Chinese hamster ovary (CHO) cells were transfected withboth genes encoding erythropoietin (Epo) and epidermal growthfactor receptor (EGFR). The transfection of the Epo gene wasconfirmed by an enzyme-linked immunoassay. Overexpression ofEGFR was confirmed by Western blotting of EGFR. Thetransfected CHO cells were cultured in serum-free medium inthe presence of soluble epidermal growth factor (EGF) orimmobilized EGF. The CHO cells overexpressing EGFR grew in thepresence of less EGF than the cells not overexpressing EGFR.In addition, the growth of EGFR-overexpressing CHO cells wasenhanced in the presence of immobilized EGF more efficientlythan in the presence of soluble EGF. The amount of Eposecreted from the cells increased linearly with the increaseof growth rate. Consequently, culture of CHO cellscoexpressing Epo and EGFR on EGF-immobilized matrix was themost efficient for Epo production.

Tissue-specific regulation of erythropoietin production in the murine kidney, brain, and uterus

Erythropoietin (Epo) produced by the kidney regulates erythropoiesis. Recent evidence suggests that Epo in the cerebrum prevents neuron death and Epo in the uterus induces estrogen (E(2))-dependent uterine angiogenesis. To elucidate how Epo expression is regulated in these tissues, ovariectomized mice were given E(2) and/or exposed to hypoxia, and the temporal patterns of Epo mRNA levels were examined. Epo mRNA levels in the kidney and cerebrum were elevated markedly within 4 h after exposure to hypoxia. Although the elevated level of Epo mRNA in the kidney decreased markedly within 8 h despite continuous hypoxia, the high level in the cerebrum was sustained for > or = 24 h, indicating that downregulation operates in the kidney but not in the brain. E(2) transiently induced Epo mRNA in the uterus but not in the kidney and cerebrum. Interestingly, the uterine Epo mRNA was hypoxia inducible only in the presence of E(2). Thus Epo expression appears to be regulated in a tissue-specific manner, endorsing the tissue-specific functions of Epo.

Complete genome sequence of the alkaliphilic bacterium Bacillus halodurans and genomic sequence comparison with Bacillus subtilis

The 4 202 353 bp genome of the alkaliphilic bacterium Bacillus halodurans C-125 contains 4066 predicted protein coding sequences (CDSs), 2141 (52.7%) of which have functional assignments, 1182 (29%) of which are conserved CDSs with unknown function and 743 (18. 3%) of which have no match to any protein database. Among the total CDSs, 8.8% match sequences of proteins found only in Bacillus subtilis and 66.7% are widely conserved in comparison with the proteins of various organisms, including B.subtilis. The B. halodurans genome contains 112 transposase genes, indicating that transposases have played an important evolutionary role in horizontal gene transfer and also in internal genetic rearrangement in the genome. Strain C-125 lacks some of the necessary genes for competence, such as comS, srfA and rapC, supporting the fact that competence has not been demonstrated experimentally in C-125. There is no paralog of tupA, encoding teichuronopeptide, which contributes to alkaliphily, in the C-125 genome and an ortholog of tupA cannot be found in the B.subtilis genome. Out of 11 sigma factors which belong to the extracytoplasmic function family, 10 are unique to B. halodurans, suggesting that they may have a role in the special mechanism of adaptation to an alkaline environment.

Identification of a sequential B-cell epitope on major allergen (Cry j 1) of Japanese cedar (Cryptomeria japonica) pollen in mice

BACKGROUND

Japanese cedar (Cryptomeria japonica; CJ) pollinosis is one of the most common allergic diseases in Japan. B cell epitopes on Cry j 1, a major allergen of CJ pollen, have been analyzed by the specific monoclonal antibodies to Cry j 1, and most of these epitopes may be conformational, but no previous report has addressed the analysis of sequential epitope mapping with synthetic peptides. The main purpose of the present study is to identify IgE and IgG B cell epitopes on Cry j 1 by using a synthetic peptide approach in mice.

METHODS

We synthesized 35 overlapping peptides that cover the entire length of Cry j 1 and examined whether mouse IgE and IgG antibodies produced by immunization with Cry j 1 reacted to the Cry j 1 peptides.

RESULTS AND CONCLUSION

We found that mouse IgE and IgG antibodies reacted strongly to Cry j 1 peptide No. 15 ((141)GVEPVHPQDGDALTLRTATN(160)), though those antibodies did not react with other peptides. IgE and IgG antibody binding to peptide No. 15 was completely inhibited by Cry j 1 and the peptide. To determine the minimum epitope in peptide No. 15, we conducted an ELISA inhibition test. IgE and IgG antibody binding to peptide No. 15 was inhibited by smaller peptides of this peptide. We found the core of the epitope to be (145)VHPQDGDA(152).

Retinoic acid stimulates erythropoietin gene transcription in embryonal carcinoma cells through the direct repeat of a steroid/thyroid hormone receptor response element half-site in the hypoxia-response enhancer

We have previously reported that expression of the erythropoietin (Epo) gene in mouse embryonal cells was not induced by hypoxia, although hypoxia induced other hypoxia-inducible genes. This study identifies retinoic acid (RA) as an inducer for Epo production in the embryonal carcinoma cell lines P19 and F9. RA induced Epo production through the transcriptional activation of the Epo gene in an oxygen-independent manner. With the use of reporter assays in P19 cells, it is shown that a direct repeat of the nuclear hormone receptor-binding motif separated by a 2-bp spacer (DR-2) in the hypoxia-response enhancer was responsible for the transcriptional activation by RA. Electrophoretic mobility shift assays show that nuclear extracts from P19 cells contained RA receptor complexes that bound to DR-2. In human hepatoma Hep3B cells, an orphan receptor, hepatocyte nuclear factor-4, strongly augmented hypoxic induction of the Epo gene in cooperation with hypoxia-inducible factor-1 (HIF-1) by binding to DR-2, whereas in P19 cells, the interaction of RA receptors with DR-2 was sufficient for RA-induced transcriptional activation of the Epo gene without the requirement of the HIF-1 site. These results suggest that DR-2 regulates expression of the Epo gene by acting as the binding site for different transcription factors in different types of cells.

Increased risk of prostate cancer and benign prostatic hyperplasia associated with a CYP17 gene polymorphism with a gene dosage effect

The CYP17 gene (CYP17) codes for the cytochrome P450c17alpha enzyme, which mediates two key steps in the sex steroid synthesis. There is a polymorphism (a T-to-C substitution) in the 5'-untranslated region, which may influence the transcription level of CYP17 mRNA. There is a continuing controversy as to whether the variant allele is associated with a subset of breast cancer or polycystic ovary syndrome. In prostate cancer research, there are contradictory data concerning the CYP17 risk allele. We explored the association between CYP17 polymorphism and a risk of prostate cancer or benign prostatic hyperplasia (BPH) in a Japanese population. This study included 252 prostate cancer patients, 202 BPH patients, and 131 male controls. A 451-bp fragment encompassing the polymorphic site was amplified by PCR, treated with restriction enzyme MspA1, and electrophoresed on an agarose gel. The MspA1-undigested allele with the published sequence and the MspA1-digested variant allele were designated as A1 and A2, respectively. There was a significant difference (P < 0.05) in the genotypes between prostate cancer patients and male controls, and between BPH patients and male controls. Men with the A1/A1 CYP17 genotype had an increased risk of prostate cancer [odds ratio (OR), 2.57; 95% confidence interval (CI) = 1.39-4.78] and BPH (OR, 2.44; 95% CI = 1.26-4.72) compared with those with the A2/A2 genotype. Men with the A1/A2 genotype had an intermediate increased risk of prostate cancer (OR, 1.45; 95% CI = 0.84-2.54) and BPH (OR, 1.60; 95% CI = 0.89-2.87) compared with those with the A2/A2 genotype. The trend of an increasing risk of prostate cancer and BPH with an increasing number of the A1 allele was statistically significant (prostate cancer versus male control, P = 0.003; OR, 1.57; 95% CI = 1.16-2.12; BPH versus male control, P = 0.008; OR, 1.55; 95% CI = 1.12-2.13). There was no significant association between the CYP17 genotype and the tumor status (grade and stage) of prostate cancer. Our results suggest that the A1 allele of the CYP17 polymorphism is associated with an increased risk of prostate cancer and BPH, with a gene dosage effect. However, the CYP17 genotype does not seem to influence the disease status in prostate cancer.