Arsenite suppresses the transcriptional activity of EVI1 through the binding to CCHC-type Zn finger domain.

Transcription factor EVI1 is essential for normal hematopoiesis in embryos but is aberrantly elevated in bone marrow cells of myelodysplastic syndrome (MDS) patients. EVI1 and its downstream GATA-2 appear to be a possible therapeutic target of MDS. Here we found that treatment of EVI1-expressing K562 cells with arsenite (As(III)) reduced the mRNA and protein levels of EVI1 and GATA-2. A gel shift assay using the nuclear extract of K562 cells showed that As(III) suppressed the DNA-binding activity of EVI1. The DNA-binding activity of the recombinant EVI1 protein was also suppressed by As(III) but was recovered by excess amounts of dithiothreitol, suggesting the involvement of cysteine residues of EVI1. Since the 7th Zn finger domain of EVI1, having a motif of CCHC, is known to be involved in DNA-binding, the synthetic peptide of 7th Zn finger domain was reacted with As(III) and subjected to MALDI-TOF-MS analysis. The results showed that As(III) binds to this peptide via three cysteine residues. As(III)-induced reduction of the DNA-binding activity of the recombinant EVI1 was abolished by the mutations of each of three cysteine residues to alanine in the 7th Zn finger domain. These results demonstrate that As(III) causes the down-regulation of EVI1 and GATA-2 by inhibiting the transcriptional activity of EVI1 through the binding to the cysteine residues of CCHC-type Zn finger domain.

A phase 1 study of ramucirumab in Japanese patients with advanced solid tumors.

OBJECTIVE: Ramucirumab is a recombinant human immunoglobulin G1 monoclonal antibody targeting the vascular endothelial growth factor receptor-2. The aim of this phase 1 study was to evaluate the safety and tolerability of ramucirumab monotherapy in Japanese patients with advanced solid tumors. METHODS: Patients with solid tumors who had not responded to standard therapy or for whom no standard therapy was available received escalating doses of ramucirumab, administered once every 2 (Q2W) or 3 (Q3W) weeks. The primary objective was to establish the safety and pharmacokinetic profiles of ramucirumab. Secondary and exploratory objectives included assessment of immunogenicity and antitumor activity. ClinicalTrials.gov: NCT01005355. RESULTS: Fifteen patients were treated with ramucirumab at a dose of 6 mg/kg Q2W (N = 3), 8 mg/kg Q2W (N = 6) or 10 mg/kg Q3W (N = 6). There were no dose-limiting toxicities and the maximum tolerated dose was not reached. The most common ramucirumab-related adverse events were headache, pyrexia, hypertension and increased aspartate aminotransferase. Following single-dose administration of ramucirumab, there appeared to be a dose-proportional increase in maximum observed drug concentration but not in area under the curve. Treatment-emergent anti-ramucirumab antibodies were not detected in any patient. CONCLUSIONS: Ramucirumab monotherapy was well tolerated and feasible at the doses and schedules used in this study population of Japanese patients with advanced solid tumors.

[Abiraterone acetate(ZYTIGA®)-development and literature review].

Abiraterone acetate(AA)has been approved in more than 80 countries for the treatment of patients with metastatic castration-resistant prostate cancer(mCRPC). In July 2013, a marketing approval application for AA was submitted to the Japanese Ministry of Health, Labour, and Welfare. AA is a selective inhibitor of CYP17A1, a crucial enzyme for androgen biosynthesis. AA exerts its anti-tumor activity by directly inhibiting androgen production at all three sources, i. e., the testes, adrenal glands, and tumor itself. Data from international phase III studies and phase I and II studies in Japan have indicated that AA improves the overall survival and quality of life(QoL)of patients with mCRPC. Herein, we have summarized the development of AA and the results of important international and local clinical trials in Japan. In addition, the effect of food on AA bioavailability, concomitant steroid use, and liver function test abnormalities have been discussed regarding the appropriate use of AA.

Outcome after first relapse in adult patients with Philadelphia chromosome-negative acute lymphoblastic leukaemia.

To analyse the outcome of adult patients who developed a first relapse of acute lymphoblastic leukaemia (ALL), we collected the clinical data of 332 patients with Philadelphia-chromosome (Ph) negative ALL, aged 16-65 years, who relapsed after first complete remission (CR1) between 1998 and 2008 in 69 institutions all over Japan, including 58 patients who relapsed after allogeneic haematopoietic stem cell transplantation (Allo-HSCT) in CR1. The overall survival (OS) was 43·4% at 1 year, and 16·3% at 5 years from relapse in patients who received chemotherapy alone in CR1. Among patients who relapsed after chemotherapy alone in CR1, 123 (52·5%) achieved a second remission (CR2) following salvage chemotherapy, of whom 62 subsequently underwent Allo-HSCT during CR2. Allo-HSCT in CR2 was significantly associated with better OS. Moreover, the type of salvage chemotherapy influenced OS from relapse. A doxorubicin, vincristine, and predonisone-based (AdVP-type) regimen was related to better OS in patients with longer CR1 (more than 1 year), but was related to worse OS in patients with shorter CR1. In conclusion, the prognosis of patients with relapsed Ph-negative ALL is poor. Allo-HSCT after a first relapse could improve the prognosis. Selection of the optimal salvage chemotherapy might depend on the duration of CR1.

[Acute myeloid leukemia possibly originating from the same clone of testicular germ cell tumor].

This report describes a 30-year-old man with a testicular germ cell tumor, which later developed into acute myeloid leukemia (AML) with a common chromosomal abnormality. Testicular germ cell tumors had developed at the age of 26. He was successfully treated with surgery followed by chemotherapy.Four years after the onset of the germ cell tumor, he developed pancytopenia with elevated serum LDH. More than 95% of the bone marrow was occupied by blastic cells. These cells were CD13+, CD34+ but CD45- and MPO-. Amplification of the short arm of chromosome 12 was recognized by fluorescence in situ hybridization using the blastic cells in the bone marrow and the previous testicular tumor specimen. Because testicular germ cell tumor recurrence and other malignant tumors could be ruled out pathologically, he was diagnosed as having AML.Allogeneic stem cell transplantation from a HLA-matched sibling donor was performed after chemotherapy. As of 19 months after the transplantation, recurrence of neither AML nor testicular tumors has been observed. Because the same genetic abnormality was observed in the testicular germ cell tumor and AML in this case, the possibility of AML having a common origin with the testicular germ cell tumor is indicated.

[Autoimmune hemolytic anemia in a patient with idiopathic interstitial pneumonia].

We report a rare case of autoimmune hemolytic anemia (AIHA) complicated by idiopathic interstitial pneumonia (IIP). A sixty-year-old man was diagnosed as having IIP in January 2009. In March, when he was hospitalized for the introduction of home oxygen therapy, severe anemia was detected. Based on the findings showing elevated levels of lactate dehydrogenase and indirect bilirubin, a decreased level of haptoglobin, positive Coombs test, and splenomegaly, a diagnosis of AIHA was made. Although anti-DNA antibody was found, diagnostic criteria for systemic lupus erythematosus and other collagen diseases were not fulfilled. Therefore, we concluded that AIHA coexisted with IIP. Treatment with prednisolone led to improvement of both AIHA and IIP. There has not been any exacerbation even after a gradual reduction of prednisolone to 7.5 mg/day. Coexistence of AIHA and IIP is rare, and accumulation of case reports is needed to gain a better understanding of this condition.

[Successful treatment with rituximab in a patient with refractory thrombotic thrombocytopenic purpura refractory to plasma exchange].

We report a patient with refractory idiopathic thrombotic thrombocytopenic purpura (TTP) who was successfully treated with rituximab. A 50-year-old woman was referred to our hospital with progressive psychoneurotic symptoms, hemolytic anemia and thrombocytopenia. The diagnosis of TTP was confirmed by the absence of ADAMTS13 activity with the presence of circulating ADAMTS13 inhibitor. High-dose steroid therapy and plasma exchange were performed. Despite 21 sessions of plasma exchange, however, there was no remarkable improvement. We then administered rituximab. Fifteen days after the first infusion of rituximab, she achieved complete remission and ADAMTS13 activity increased up to 14%. The patient has remained in remission for more than 9 months.

Pemetrexed and carboplatin combination therapy followed by pemetrexed maintenance in Japanese patients with non-squamous non-small cell lung cancer: A subgroup analysis of elderly patients.

BACKGROUND: The combination of pemetrexed and carboplatin is commonly used for the treatment of advanced non-squamous non-small cell lung cancer (NSCLC), mainly because it is comparatively effective and less toxic than other platinum-doublet therapies. Using the JMII (JACAL) study, we report the efficacy and safety of this treatment followed by pemetrexed maintenance in the elderly population (≥70 years of age). METHODS: The JMII study was a multicenter, post-marketing study that assessed the efficacy and safety of carboplatin (AUC6) and pemetrexed (500 mg/m2, given on Day 1 of a 21-day cycle, 4 cycles) followed by pemetrexed (500 mg/m2) maintenance in advanced non-squamous NSCLC patients (n = 109). Retrospective subgroup analyses were performed in elderly patients aged ≥70. RESULTS: The study includes younger (<70 years, n = 84) and elderly (≥70 years, n = 25) patients who received induction therapy. Median progression-free survival and overall survival from the start of the induction phase were 5.2 (95% CI: 3.5, 8.2) and 16.8 (95% CI: 10.3, NC) months for the elderly patients compared with 5.8 (95% CI: 4.3, 7.4) and 20.5 (95% CI: 16.7, NC) months for the younger patients, respectively. Grade 3/4 hematologic toxicities were more frequent in the elderly patients. Non-hematologic toxicities in the elderly patients were comparable to those in younger patients. Dose reduction was more common in the elderly (44% vs 23%), due to hematologic toxicities. CONCLUSIONS: There was no difference in efficacy (evaluated by progression-free survival) between elderly and younger patients. Although grade 3/4 hematologic toxicities were frequently observed in the elderly patients, they were easily managed with dose adjustment.

Necitumumab plus gemcitabine and cisplatin versus gemcitabine and cisplatin alone as first-line treatment for stage IV squamous non-small cell lung cancer: A phase 1b and randomized, open-label, multicenter, phase 2 trial in Japan.

OBJECTIVES: This open-label, multicenter, phase 1b/2 study assessed necitumumab plus gemcitabine and cisplatin (GC + N) in patients with previously untreated squamous non-small cell lung cancer in Japan. MATERIALS AND METHODS: The phase 1b part determined the gemcitabine dose for the phase 2 part, in which patients were randomized 1:1 to GC + N or gemcitabine and cisplatin (GC) (gemcitabine 1250 mg/m2 on days 1 and 8; cisplatin 75 mg/m2 on day 1 of maximum four 3-week cycles; nectimumab 800 mg on days 1 and 8 of a 3-week cycle continued until progressive disease or unacceptable toxicity). The primary endpoint of the phase 2 part was overall survival. RESULTS: In the phase 2 part, 181 patients received GC + N (N = 90) or GC (N = 91). Overall survival was significantly improved with GC + N versus GC (median, 14.9 months vs 10.8 months; hazard ratio [HR] = 0.66, 95% CI: 0.47 - 0.93, p = 0.0161). Improvements were also observed in progression-free survival (median, 4.2 months vs 4.0 months; HR = 0.56; p = 0.0004) and objective response rate (51% vs 21%; p < 0.0001). Survival was also significantly prolonged with GC + N versus GC for patients with epidermal growth factor receptor-positive tumors. Grade ≥3 treatment-emergent adverse events at ≥5% higher incidence with GC + N than GC were neutrophil count decreased (42% vs 35%), febrile neutropenia (12% vs 3%), decreased appetite (11% vs 4%), and dermatitis acneiform (6% vs 0%). CONCLUSION: GC + N is well tolerated and has significant and clinically meaningful treatment benefit in the first-line treatment of patients with squamous non-small cell lung cancer in Japan. Clinicaltrials.gov identifier: NCT01763788.

Involvement of Ku80 in microhomology-mediated end joining for DNA double-strand breaks in vivo.

Mammalian cells have an activity of mutagenic repair for DNA double-strand breaks (DSBs), microhomology-mediated end joining (MMEJ), in which DNA ends are joined via microhomologous sequences flanking the breakpoint. MMEJ has been indicated to be undertaken without Ku proteins, which are essential factors for non-homologous end joining (NHEJ). On the other hand, recent studies with cell-free (in vitro) systems indicated the involvement of Ku proteins in MMEJ, suggesting that MMEJ could be also undertaken by a Ku-dependent pathway. To clarify whether Ku proteins are essential in MMEJ in vivo, linearized plasmid DNAs with microhomologous sequences of 10bp at both ends were introduced as repair substrates into Ku80-proficient and Ku80-deficient CHO cells, and were subjected to MMEJ and NHEJ. Activities of MMEJ and NHEJ, respectively, of the cells were evaluated by mathematical modeling for the increase in fluorescence of GFP proteins produced from repaired products. The Ku80 deficiency caused approximately 75% reduction of the MMEJ activity in CHO cells, while it caused is > or =90% reduction of the NHEJ activity. Therefore, it was indicated that there is a Ku-dependent pathway for MMEJ; however, MMEJ is less dependent on Ku80 protein than NHEJ. The fraction of MMEJ products increased in proportion to the increase in the amounts of substrates. The results suggest that the increase in DSBs makes the cell more predominant for MMEJ. MMEJ might function as a salvage pathway for DSBs that cannot be repaired by NHEJ.

The effects of beta(3)-adrenoceptor agonist CL-316,243 on adiponectin, adiponectin receptors and tumor necrosis factor-alpha expressions in adipose tissues of obese diabetic KKAy mice.

We investigated the effects of beta(3)-adrenoceptor agonist, 5-[(2R)-2-[[(2R)-2-(3-chlorophenyl)-2-hydroxyethyl]amino]propyl]-1,3-benzodioxole-2,2-dicarboxylate (CL-316,243) in obese diabetic KKAy mice. Two weeks' subcutaneous administration of CL-316,243 reduced serum levels of glucose, insulin, triglyceride, free fatty acid and tumor necrosis factor-alpha (TNF-alpha), and increased adiponectin. Adiponectin, adiponectin receptors and beta(3)-adrenoceptor mRNA expressions were reduced in epididymal white adipose tissue in KKAy mice, and CL-316,243 recovered these mRNA expressions. Meanwhile, CL-316,243 suppressed the overexpressed mRNA level of TNF-alpha in both epididymal white adipose tissue and brown adipose tissue. These data suggest that the normalization of adiponectin, adiponectin receptors and TNF-alpha may result in the amelioration of obesity-induced insulin resistance.

Detection of the STAT5B-RARA fusion transcript in acute promyelocytic leukemia with the normal chromosome 17 on G-banding.

Acute promyelocytic leukemia (APL) is characterized by chromosomal rearrangements of 17q21, leading to fusion of the gene-encoding retinoic acid receptor alpha (RARA) with a number of alternative partner genes. Signal transducer and activator of transcription 5 beta (STAT5B) is one of the alternative partners. We report a rare case of APL with STAT5B-RARA fusion transcript and the normal chromosome 17 on G-banding. Administration of all trans-retinoic acid improved disseminated intravascular coagulation without decrease of the leukemia cells in his peripheral blood and bone marrow. The molecular mechanism of fusion between STAT5B and RARA by chromosomal rearrangement is discussed based on the data from genome database. Clinical characteristics of APL with STAT5B-RARA are also discussed.

beta-adrenoceptor agonists downregulate adiponectin, but upregulate adiponectin receptor 2 and tumor necrosis factor-alpha expression in adipocytes.

Recently, the insulin-sensitizing adipokine adiponectin and the insulin resistance-inducing adipokine tumor necrosis factor-alpha (TNF-alpha) were reported to inhibit each other's production in adipocytes. We investigated the effects of two beta(3)-adrenoceptor agonists, 5-[(2R)-2-[[(2R)-2-(3-chlorophenyl)-2-hydroxyethyl]amino]propyl]-1,3-benzodioxole-2,2-dicarboxylate (CL-316,243) and (+/-)-(R(*),R(*))-[4-[2-[[2-(3-chlorophenyl)-2-hydroxyethyl]amino]propyl]phenoxy]acetic acid (BRL37344), on the gene expression of adiponectin, two adiponectin receptors, and TNF-alpha in adipose tissues of C57BL/6J mice. CL-316,243 and BRL37344 downregulated adiponectin, but upregulated adiponectin receptor 2 (not receptor 1) in epididymal or/and subcutaneous white adipose tissues and in brown adipose tissue. TNF-alpha expression was upregulated only in epididymal adipose tissue. To further explore these effects, we treated differentiated 3T3-L1 adipocytes with the non-selective beta-adrenoceptor agonist isoproterenol. As a result, adiponectin receptor 2 (but not receptor 1) gene expression and TNF-alpha protein expression increased, but gene expression and secretion of adiponectin decreased. The upregulation of adiponectin receptor 2 by isoproterenol is most likely via beta(2),beta(3)-adrenoceptors, adenylyl cyclases, and protein kinase A (PKA). However, the accompanying activation of AMP-activated protein kinase (AMPK) may inhibit this upregulation. Our results suggest that upregulation of TNF-alpha and downregulation of adiponectin by beta-adrenoceptor activation may contribute to the pathogenesis of catecholamine-induced insulin resistance, and that upregulation of adiponectin receptor 2 may be a feedback result of reduced adiponectin.

Novel germline mutations in the SDHB and SDHD genes in Japanese pheochromocytomas.

The SDHA, SDHB, SDHC, and SDHD genes code for subunits of succinate dehydrogenase (SDH), which forms part of the mitochondrial respiratory chain. Germline mutations in the genes encoding SDHB and SDHD have been reported in familial paragangliomas/pheochromocytomas and in apparently sporadic pheochromocytomas. SDHB and SDHD mutations are widely distributed along the genes with no apparent hot spots. SDHB mutations are often detected in malignant and extra-adrenal pheochromocytomas. SDHD mutations are also detected frequently in head and neck paragangliomas. We sequenced the entire coding regions of the SDHB and SDHD genes in 17 pheochromocytomas. We identified novel heterozygous G to A point mutations at the first base of intron 3 of the SDHB gene in a malignant extra-adrenal abdominal pheochromocytoma patient, and at the first base of codon 111 of the SDHD gene in an adrenal pheochromocytoma patient. Further, we confirmed the SDHD mutation by DHPLC. The prevalence of SDHB and SDHD mutations in pheochromocytomas we examined was 12% (2/17). Thus, we identified two novel SDH mutations in Japanese pheochromocytomas. Further studies will investigate the oncogenic potential of these mutations.

Successful treatment of a patient with POEMS syndrome by tandem high-dose chemotherapy with autologous CD34+ purged stem cell rescue.

A 36-year-old man was admitted because of numbness and muscle weakness in the lower extremities. He had gait disturbance, malaise, and body weight loss. Based on the existence of monoclonal gammopathy, the proliferation of abnormal plasma cells in the bone marrow, the presence of sclerotic bone lesion, polycythemia, mild splenomegaly, and an elevated level of serum vascular endothelial growth factor (VEGF) (14,900 pg/mL; normal, 62-707), he was diagnosed as having peripheral neuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome. Following 2 courses of conventional chemotherapy with doxorubicin and dexamethasone, peripheral blood stem cells were mobilized by high-dose etoposide (500 mg/m(2) x 3 days) and granulocyte colony-stimulating factor. After purging by CD34+ selection using the CliniMACS device, the selected cells (12.4 x 10(6)/kg) were cryopreserved. He was then treated with tandem high-dose chemotherapy (HDC) (melphalan 100 mg/m(2) x 2 days) with autologous stem cell rescue. After the first course of HDC, the serum level of VEGF normalized and the minimal residual disease in the bone marrow was reduced below the detection limit of CDR3 analysis by polymerase chain reaction. The patient has been in remission for more than 20 months. He has gradually recovered from the neurological symptoms and now has no impairments of daily living. Our experience suggests that autologous purged stem cell transplantation should be considered as the treatment of choice for POEMS syndrome.

Therapy-related acute myeloid leukemia 6 years after clonal detection of inv(11)(q21q23) and MLL gene rearrangement.

Results of recent studies with animal models suggest that expression of MLL fusion proteins promotes acute leukemogenesis. However, the most potent MLL fusion proteins are not sufficient for the development of acute myeloid leukemia (AML). The clinical data on the pathogenesis of this type of leukemia are limited. We analyzed the case of a patient with therapy-related AML with MLL rearrangement. The patient initially developed AML with t(8;21). Although the patient achieved complete remission with chemotherapy, an abnormal karyotype, inv(11)(q21q23), was detected. After 6-year persistence of a clone with the inversion 11 karyotype in the bone marrow, secondary AML developed. Results of fluorescence in situ hybridization analysis combined with magnet-activated cell sorting analysis showed that MLL rearrangement was detected in CD34+ and CD13+ fractions but not in a CD3+ fraction of the bone marrow. There were 2 important clinical findings. One was that MLL rearrangement was not sufficient for the development of leukemia. The other was that MLL rearrangement targets specific lineages.

Arsenic trioxide augments all-trans retinoic acid-induced differentiation of HL-60 cells.

AIMS: All-trans retinoic acid (ATRA) is used to treat patients with acute promyelocytic leukemia (APL) due to its ability to resume the differentiation of APL cells. Recently, clinical trials have been started to evaluate ATRA plus arsenic trioxide (ATO) as a combination treatment for APL patients. However, little is known about the detailed mechanisms underlying its efficacy. We therefore investigated the effects of this combination on the differentiation and differentiation-related gene expression. MAIN METHODS: Human leukemia HL-60 cells differentiation was examined using nitro blue tetrazolium and CD11b. The levels of mRNA and protein were determined by RT-qPCR, microarray, western blot and ELISA, respectively. The promoter activity was assessed by luciferase activity. The arsenic concentration was determined by ICP-MS. KEY FINDINGS: ATRA-induced HL-60 differentiation was augmented by co-treatment with ATO. A microarray analysis showed that ATRA plus ATO treatment markedly down-regulated the expression of proteinase 3 (PRTN3), which is involved in the differentiation arrest of leukemia cells, compared with treatment with ATRA alone. The PRTN3 mRNA level was suppressed by treatment with ATRA alone, and then further suppressed by co-treatment with ATO, accompanied by a concomitant increase in Sp1 protein, which is known to facilitate differentiation. The expression levels of azurocidin, telomerase reverse transcriptase, ferritin, and interleukin-1ß were also altered by co-treatment with ATO. SIGNIFICANCE: Co-treatment with ATO enhances ATRA-induced HL-60 differentiation by altering the expression of genes involved in cell differentiation, providing the molecular basis for a combination therapy using ATO plus ATRA to treat leukemia patients.

AP-1 transrepressing retinoic acid does not deplete coactivators or AP-1 monomers but may target specific Jun or Fos containing dimers.

Retinoic acid (RA) inhibits tumor promotion in many models in vivo and in vitro, among them mouse epidermal JB6 cells. RA treatment suppresses 12-O-tetradecanoylphorbol-13-acetate (TPA) induced AP-1 activity, an activity that is required for transformation of JB6 P+ cells. The molecular mechanism of AP-1 transrepression by retinoids is unclear, especially as related to inhibition of transformation. Overexpression of AP-1 components did not rescue TPA induced AP-1 activation nor did a GST pull down experiment implicate direct binding, thus rendering unlikely both a Jun/Fos-RA-RAR direct interaction and a Jun/Fos sequestration mechanism. Overexpression of p300, SRC-1 or pCAF did not abrogate AP-1 suppression by RA, thus arguing against coactivator competition. Overexpression of the corepressor silencing mediator for retinoic acid and thyroid hormone receptors (SMRT) suppressed AP-1 activity. However, SMRT but not RA inhibited cJun transactivation, suggesting SMRT does not mediate RA transrepression. RA treatment also did not block TPA induced ERK phosphorylation, Jun/Fos family protein expression except for cFos, or DNA binding of the AP-1 complex. The transcriptional activities of full-length JunB and full-length Fra-1, but not the transactivation domain fusions, were increased by TPA treatment and suppressed by RA. Since these full-length fusions have bzip domains, the results suggest that JunB and/or Fra-1-containing dimers may constitute one target of RA for transrepression of AP-1.