Physical association of the patient-specific GATA1 mutants with RUNX1 in acute megakaryoblastic leukemia accompanying Down syndrome.

Mutations of the GATA1 gene on chromosome X have been found in almost all cases of transient myeloproliferative disorder and acute megakaryoblastic leukemia (AMKL) accompanying Down syndrome (DS). Although most GATA1 mutations lead to the expression of GATA1s lacking the N-terminal activation domain, we recently found two novel GATA1 proteins with defects in another N-terminal region. It has been suggested that loss of the N-terminal portion of GATA1 might interfere with physiological interactions with the critical megakaryocytic transcription factor RUNX1, and this would imply that GATA1s is not able to interact properly with RUNX1. However, the interaction domain of GATA1 remains controversial. In this study, we show that GATA1 binds to RUNX1 through its zinc-finger domains, and that the C-finger is indispensable for synergy with RUNX1. All of the patient-specific GATA1 mutants interacted efficiently with RUNX1 and retained their ability to act synergistically with RUNX1 on the megakaryocytic GP1balpha promoter, whereas the levels of transcriptional activities were diverse among the mutants. Thus, our data indicate that physical interaction and synergy between GATA1 and RUNX1 are retained in DS-AMKL, although it is still possible that increased RUNX1 activity plays a role in the development of leukemia in DS.

Cerebral venous thrombosis in adult nephrotic syndrome due to systemic amyloidosis.

Although venous thrombosis is one of the common complications in nephrotic patients, cerebral venous thrombosis (CVT) is rarely reported. CVT is so difficult to be detected by conventional diagnostic methods that it is sometimes overlooked despite its potential severity. We report a 79-year-old female with nephrotic syndrome due to systemic amyloidosis who suddenly altered mental status during her hospitalization. The underlying etiology had been not identified by physical examinations, various laboratory data, and repeated computed tomography, and finally she died. The post-mortem examination showed a massive thrombus impacted in intracranial left-sided transverse and sigmoid sinus. This case suggests that CVT can occur in a nephrotic patient who presents unexplained neurological signs and symptoms, which might not be detected only through conventional diagnostic tests.

Human small Maf proteins form heterodimers with CNC family transcription factors and recognize the NF-E2 motif.

The transcription factor NF-E2, a heterodimeric protein complex composed of p45 and small Maf family proteins, is considered crucial for the regulation of erythroid gene expression and platelet formation. To facilitate the characterization of NF-E2 functions in human cells, we isolated cDNAs encoding two members of the small Maf family, MafK and MafG. The human mafK and mafG genes encode proteins of 156 and 162 amino acid residues, respectively, whose deduced amino acid sequences show approximately 95% identity to their respective chicken counterparts. Expression of mafK mRNA is high in heart, skeletal muscle and placenta, whereas mafG mRNA is abundant in skeletal muscle and is moderately expressed in heart and brain. Both are expressed in all hematopoietic cell lines, including those of erythroid and megakaryocytic lineages. In electrophoretic gel mobility shift assays binding to NF-E2 sites was found to depend on formation of homodimers or heterodimers with p45 and p45-related CNC family proteins. The results suggest that the small Maf family proteins function in human cells through interaction with various basic-leucine zipper-type transcription factors.

Cloning and expression of human B cell-specific transcription factor BACH2 mapped to chromosome 6q15.

The transcription factor Bach2, a member of the BTB-basic region leucine zipper (bZip) factor family, binds to a 12-O-tetradecanoylphorbol-13-acetate (TPA)-responsive element and the related Maf-recognition element (MARE) by forming homodimers or heterodimers with Maf-related transcription factors. Bach2 regulates transcription by binding to these elements. To understand the function in hematopoiesis, we isolated a cDNA clone for human Bach2 (BACH2) encoding a protein of 841 amino acid residues with a deduced amino acid sequence having 89.5% identity to mouse homolog. Among human hematopoietic cell lines, BACH2 is expressed abundantly only in some B-lymphocytic cell lines. RT-PCR analysis of hematopoietic cells revealed that BACH2 mRNA is expressed in primary B-cells. Enforced expression of BACH2 in a human Burkitt cell line, RAJI that does not express endogenous BACH2, resulted in marked reduction of clonogenic activity, indicating that BACH2 possesses an inhibitory effect on cell proliferation. By fluorescent in situ hybridization, the BACH2 gene was localized to chromosome 6q15. Because deletion of the long arm of chromosome 6 (6q) is one of the commonest chromosomal alterations in human B-cell lymphoma, we examined for the loss of heterozygosity (LOH) of the BACH2 gene in human B-cell non-Hodgkin's lymphomas (NHL). Among 25 informative cases, five (20%) showed LOH. These results indicate that BACH2 plays important roles in regulation of B cell development.

Desferrioxamine, an iron chelator, upregulates cyclooxygenase-2 expression and prostaglandin production in a human macrophage cell line.

Prostaglandins (PGs) play regulatory roles in a variety of physiological and pathological processes, including the immune response, cytoprotection and inflammation. Desferrioxamine (DFX), an iron chelator, is known to reduce free radical-mediated cell injury and to upregulate certain inflammatory mediators. We investigated the effects of DFX on the production of PGs and the expression of cyclooxygenase-2 (COX-2), the rate-limiting enzyme in the synthesis of PGs, using a human macrophage cell line, U937. Our results showed that COX-2 expression and PGE(2) production are upregulated by DFX treatment and that this upregulation is dependent on both COX-2 promoter activity and alteration of mRNA stability. COX-2 promoter activity may be, at least in part, mediated by activation of the extracellular signal-regulated kinase pathway. These findings suggest that iron metabolism may regulate inflammatory processes by modulating PGs as well as other inflammatory mediators.

Functional characterization of the two alternative promoters of human p45 NF-E2 gene.

OBJECTIVE: The transcription factor NF-E2, a heterodimeric protein complex composed of p45 and small Maf family proteins, is considered crucial for the proper differentiation of erythrocytes and megakaryocytes in vivo. We report the results of studies aimed at understanding the regulatory mechanisms controlling p45 gene expression in erythroid cells. MATERIALS AND METHODS: Human p45 mRNAs have two alternative isoforms, aNF-E2 and fNF-E2, and these isoforms are transcribed from the alternative promoters. We investigated lineage-specific expression of both isomers in human erythroid and megakaryocytic cells by reverse transcriptase polymerase chain reaction or Northern blot analysis. For functional characterization of both promoters, plasmids in which reporter genes were placed under the control of a series of truncated or mutated promoter fragments were transfected to human hematopoietic cell lines. RESULTS: When CD34(+) cells isolated from human cord blood were induced to unilineage erythroid or megakaryocytic differentiation in liquid suspension culture, both transcripts, although barely detected at day 0, were induced in both erythroid and megakaryocytic cultures. fNF-E2 mRNA was found to be more abundant in erythroid cells than megakaryocytic cells at day 7 of culture. Although both isomers were expressed in human erythroid-megakaryocytic cell lines, megakaryocytic maturation with loss of erythroid phenotype induced by phorbol 12-myristate 13-acetate (PMA) resulted in exclusive downregulation of fNF-E2, suggesting that fNF-E2 promoter is more erythroid specific. Functional analysis of fNF-E2 promoter showed that the promoter is active only in erythroid-megakaryocytic cells and that the double GATA site in the proximal region is necessary for its efficient activity. CONCLUSION: These results suggest that GATA proteins, which govern the differentiation of erythroid lineage cells, are required for full promoter activity of the p45 gene.

Basaloid and warty carcinomas of the vulva. Distinctive types of squamous cell carcinoma frequently associated with human papillomaviruses.

In a previous study, we described an elevated prevalence of human papillomavirus (HPV) in two specific types of squamous cell carcinoma of the vulva designated basaloid carcinoma (BC) and warty carcinoma (WC) compared with the conventional type of keratinizing squamous cell carcinoma (KSC). To determine whether there were other differences in their clinical presentation or behavior, we examined 100 cases of squamous cell carcinoma of the vulva classified as BC (28 cases), WC (seven cases), and KSC (65 cases). We included only cases in which tissue adjacent to the tumor was present so that the presence of intraepithelial lesions (squamous hyperplasia, lichen sclerosus, and vulvar intraepithelial neoplasia [VIN]) could be correlated with the different types of invasive carcinomas. Microscopically, BC was characterized by a relatively uniform population of small, ovoid cells with a high nuclear-cytoplasmic ratio resembling VIN 3. Although WC was similar to typical squamous cell carcinoma, it contained many squamous cells that displayed marked nuclear pleomorphism, enlargement, atypia, and multinucleation in conjunction with cytoplasmic cavitation resembling koilocytotic atypia in intraepithelial lesions. The majority of the women with BC and WC were less than 60 years of age, and the proportion of black women was higher as compared with the women with KSC, the majority of whom were white and over 65 years of age. On crude comparison, women with BC appeared to have a survival advantage compared with women with KSC; however, through multivariate modelling, when all possible confounding variables were taken into account, there was little residual impression of a survival advantage of women with BC compared with those having KSC. Substantial differences were found among the three types of carcinoma with regard to the prevalence of adjacent intraepithelial lesions. Squamous hyperplasia was found adjacent to KSC in 54 (83%) of the 65 cases, whereas 27 (77%) of 35 cases of BC and WC had adjacent basaloid or warty VIN. These findings suggest that VIN is a precursor of BC and WC. In view of the high frequency of HPV-DNA detected in VIN and in BC and WC, the findings support the view that HPV has a role in the development of these tumors. In addition, a difference was found in the distribution of associated cervical and vaginal tumors with the three types of vulvar carcinomas.(ABSTRACT TRUNCATED AT 400 WORDS)

A new view of the so-called adenoma malignum of the uterine cervix.

Adenoma malignum of the uterine cervix (mucinous type of minimal deviation adenocarcinoma, mucinous MDA), is a unique neoplasm that is difficult to diagnose owing to the deceptively benign appearance of the tumour cells. The present study was undertaken to explore the phenotypic expression of this tumour compared with those of non-neoplastic cervical tissues and of cervical carcinomas of various types. Ten cases of mucinous MDA, 50 cases with non-neoplastic cervical tissues, 13 of cervical adenocarcinoma including the mucinous (endocervical or intestinal type) and endometrioid types, and 2 of mucoepidermoid carcinoma were examined by various histochemical staining methods, including those for gastric mucins, pepsinogen, lysozyme, chromogranin A and carcinoembryonic antigen. The results revealed that mucinous MDA characteristically exhibited gastric phenotypes. The presence of gastric metaplasia was also demonstrated in 9 cases of mucinous MDA and in 5 of the other cases examined. The 7 endocervical-type adenocarcinomas also included 4 that expressed gastric phenotypes, and 2 of the 3 intestinal-type adenocarcinomas showed the same properties focally. These results indicate the presence of a group of lesions expressing gastric phenotypes in the uterine cervix and suggest a close relationship between these lesions. Cervical adenocarcinomas expressing gastric phenotypes are probably derived from MDA.

Progression from myelodysplastic syndrome with monosomy 7 to acute monoblastic leukemia with MLL gene rearrangement.

We report a case of myelodysplastic syndrome (MDS) with the 11q23 translocation at its leukemic transformation. Southern blot analysis demonstrated that the MLL gene on chromosome 11 was rearranged during the progression from MDS to acute leukemia. The clinical observation in this case supports the notion that leukemic transformation involves multiple cytogenetic evolutionary progresses, and that MLL gene rearrangement corresponds to the final step of leukemogenesis.

Expression of erythroid-specific genes in megakaryoblastic disorders.

Currently available data indicate that erythroid and megakaryocytic differentiation pathways are closely related to each other, and there may exist progenitor cells common to those two lineages may exist. Acute megakaryoblastic leukemia (AML-M7) and transient myeloproliferative disorder in Down's syndrome (TMD) are characterized by rapid growth of abnormal blast cells which express megakaryocytic markers. These blast cells express lineage-specific transcription factors such as GATA-1 common to these lineages and frequently express erythroid-specific mRNAs such as gamma-globin and erythroid delta-aminolevulinate synthase (ALAS-E), indicating that most of the blasts in M7 and TMD cases have erythroid and megakaryocytic phenotypes. These results suggest that blasts in M7 and TMD may correspond to progenitors of both erythroid and megakaryocytic lineages.

New multi-disciplinary treatment modality with RALS for patients with esophageal cancer.

Esophageal cancer is frequently found when it is already in the advanced stage and curative surgery for such cases is consequently difficult to perform. The new multi-disciplinary treatment for esophageal cancer presented here was, therefore, conceived to improve both the survival rate and quality of life of these patients. This combined treatment modality consists of limited surgery, external irradiation, intracavitary irradiation with remote-controlled after-loading system (RALS) and peri-operative chemotherapy. In the present series, 45 patients with esophageal cancer received esophagectomy and on another 11 patients bypass operation was performed. All patients were treated with this multi-disciplinary treatment after operation. A 3 cm-wide thin gastric tube was made from the greater curvature of the stomach of the patient using an autosuture apparatus (PLC55 or GIA). In the bypass operation, the jejunum was anastomosed to the original esophagus in the Roux-en Y fashion and jejunostomy was performed on the oral side of the Roux loop. A silastic tube of 9 mm inner diameter was inserted from the jejunostomy and placed into the original esophagus for the purpose of postoperative intracavitary irradiation with RALS. For the patients receiving esophagectomy, a similar silastic tube was also placed in the posterior mediastinum for intracavitary irradiation with RALS. The indication of the bypass operation was i) a tumor length longer than 9 cm on the X-ray film and/or ii) direct invasion to the aortic wall evident by CT or MRI examination. Two weeks after the operation, external irradiation to the mediastinum with Linac 10 MV X-ray, and to the bilateral cervical regions with Linac 15 MeV electron beam, was started. The irradiation doses were 30 Gy (2 Gy/day, 5 times/ week) and 48 Gy (4 Gy/day, 3 times/week), respectively. The intracavitary irradiation with RALS was started shortly before the end of the external irradiation period and was delivered from a 60Co source. The total dose was 24 Gy (6 Gy/day, once a week) for the esophagectomized cases, and 18 Gy for the bypassed cases. Two or three weeks after the termination of the radiotherapy, chemotherapy with cisplatinum and 5-fluorouracil was performed and repeated every 6 months for 2 years. All patients could eat normally and were discharged after finishing the first chemotherapy session. The overall 5-year survival rate was 49% for the esophagectomized cases and 11% for the bypassed cases. The longest survival time in the bypassed cases was 5 years and 4 months. Neither operative death nor severe complications were experienced during the treatment period. The results indicate that this newly developed multi-disciplinary treatment with RALS can improve the prognosis and the quality of life not only in the esophagectomized patients but also in the bypassed patients with advanced esophageal cancer.

The well-balanced nucleoside-nucleotide mixture "OG-VI" for special medical purposes.

Nucleotides and nucleosides are essential components in all cells. However, nucleotides have not been supplied in parenteral nutrition regimens. We developed a well-balanced nucleoside-nucleotide mixture "OG-VI" and examined its effect in animals under some stressed conditions. OG-VI was composed of 30 mmol/l of inosine, 30 mmol/l of guanosine monophosphate, 30 mmol/l of cytidine, 22.5 mmol/l of uridine and 7.4 mmol/l of thymidine. The whole body protein turnover increased significantly in rats receiving total parenteral nutrition (TPN) with OG-VI solution after 70% hepatectomy, compared with rats receiving normal TPN without OG-VI (122.1 +/- 20.9 mgN.kg-1.h-1 vs. 97.4 +/- 10.1 mgN.kg-1.h-1, P < 0.01, n = 10). OG-VI significantly enhanced protein synthesis while it did not decrease protein breakdown. The effect of OG-VI on myocardium after hypoxic challenge was also examined in rats. The creatine phosphate (PCr)/inorganic phosphate (Pi) was decreased in normal rat myocardium after hypoxic challenge. However, in the rats administered OG-VI, PCr/Pi was maintained at baseline level and did not decrease after hypoxia. There was no significant change in the level of adenosine triphosphate (ATP) between before and after hypoxic challenge in myocardium of the rats administered OG-VI. In the rats receiving normal saline, instead of OG-VI, the ATP level decreased significantly after hypoxic challenge (4132 +/- 276 nmol/g tissue, n = 3, vs. 3439 +/- 465 nmol/g tissue, n = 5, P < 0.05). These data suggested that the well-balanced nucleoside-nucleotide mixture, OG-VI improved nitrogen metabolism and might stimulate synthesis of high-energy phosphate in recovery after severe surgical stress.

Loss of heterozygosity among tumor suppressor genes in invasive and in situ carcinoma of the uterine cervix.

The aim of the present study was to further clarify the histogenesis of cervical carcinoma by investigating loss of heterozygosity (LOH) among a number of tumor suppressor genes in invasive and in situ carcinoma of the cervix. Materials consisted of 16 in situ and 29 invasive carcinomas (16 squamous cell carcinomas, nine adenocarcinomas, and four adenosquamous carcinomas). DNA samples were collected by microdissection from ordinary formalin-fixed, paraffin-embedded tissues, both from the lesions and from normal tissues. LOH was analyzed using eight DNA polymorphic tumor suppressor markers. Of the 16 cases of carcinoma in situ, three cases exhibited LOH at one locus. Of the 29 cases of invasive carcinomas, six cases exhibited LOH at two loci and nine cases exhibited LOH at one locus. Overall, LOH was found more frequently in invasive carcinomas than in in situ carcinomas. LOH was most frequently detected at the PTCH (Drosophila patched gene) locus. There was no significant correlation between LOH at a specific site and either histologic subtype or clinical stage. These results suggest that LOH might already occur in a fraction of preinvasive squamous lesions and that accumulation of LOH may in part play a role in carcinogenesis of the cervix.

Dynamic MR appearance of benign phyllodes tumor of the breast in a 20-year-old woman.

We describe a 20-year-old woman with benign phyllodes tumor of the left breast. Dynamic MRI demonstrated a multi-lobulated lesion rapidly and markedly enhanced on dynamic studies of contrast-enhanced T1-weighted imaging without washout. Histological examination of an excisional biopsy specimen obtained under local anesthesia disclosed a well-circumscribed multi-lobulated lesion, confirming the diagnosis of benign phyllodes tumor of the breast.

[Severe aplastic anemia successfully treated with cyclosporin A and prednisolone].

A 7-year-old boy was admitted to our department complaining pale face and subcutaneous bleeding in August, 1987. Peripheral blood analysis showed pancytopenia of WBC 2,600/microliter, RBC 148 x 10(4)/microliter and platelets 5,000/microliter. Bone marrow biopsy revealed hypocellularity. Granulocytes 104/microliter, reticulocytes 4,290/microliter and platelets 5,000/microliter were compatible with the diagnosis of severe aplastic anemia based on the criteria of the Ministry of Public Welfare in Japan. Prednisolone (PDN) was initially indicated and bolus methylprednisolone, metenolone and ALG therapy followed with no hematological improvement. Fifteen months after admission, in addition to 0.5-1 mg/kg/day of metenolone, Cyclosporin A (CyA) was started at a dose of 12 mg/kg/day for a week and 6 mg/kg/day thereafter. After a week from administration of CyA, 1 mg/kg/day of PDN was given because his bleeding tendency became worse. But this combination was complicated with liver damage and hyperglycemia to discontinue both drugs. These adverse effects were subsided within 7 days by cessation of the drugs. CyA was started again at a dose of 6 mg/kg/day without any response for 4 weeks. Then PDN was added together at a reduced dose of 0.5-1 mg/kg/day. Hematological response was obtained promptly. Granulocytes reached 1,500/microliter, hemoglobin 10.2 g/dl and platelets 26,000/microliter after 3 months of therapy. Afterward the patient became transfusion independent. The most effective method of CyA administration for aplastic anemia is still controversial. Alternative use of CyA, considering combination of steroids or anabolic steroids, in patients who failed to respond to conventional immunosuppressive treatments should be further investigated.

Changes in significance of axillary lymph node dissection for patients with breast cancer.

Axillary lymph node dissection has been a routine part of breast cancer treatment for more than 100 years. As so few patients have been shown to have positive nodes, more consideration should be given to eliminating axillary node dissection for duct carcinoma in situ (DCIS) and T1a lesions. And for patients with T1/2N0M0 cancer of the breast, lumpectomy alone without axillary dissection followed by radiation therapy of the intact breast and regional lymph nodes should be a reasonable treatment without any arm morbidity. Between September 1989 and September 1994, we have treated 40 breast cancer patients with this method and no local recurrence nor distant metastasis has been encountered so far. Therefore, it is concluded that axillary dissection should be performed routinely only for N1b lesions and larger.