Identification of putative noncanonical driver mutations in patients with essential thrombocythemia

Essential thrombocythemia (ET) cases without canonical JAK2, CALR, or MPL mutations, that is, triple-negative (TN) ET, have been found in 10%-20% of ET cases. Owing to the limited number of TN ET cases, its clinical significance remains unclear. This study evaluated TN ET's clinical characteristics and identified novel driver mutations. Among 119 patients with ET, 20 (16.8%) had no canonical JAK2/CALR/MPL mutations. Patients with TN ET tended to be younger and had lower white blood cell counts and lactate dehydrogenase values. We identified putative driver mutations in 7 (35%): MPL S204P, MPL L265F, JAK2 R683G, and JAK2 T875N were previously reported as candidate driver mutations in ET. Moreover, we identified a THPO splicing site mutation, MPL*636Wext*12, and MPL E237K. Four of the seven identified driver mutations were germline. Functional studies on MPL*636Wext*12 and MPL E237K revealed that they are gain-of-function mutants that increase MPL signaling and confer thrombopoietin hypersensitivity with very low efficiency. Patients with TN ET tended to be younger, although this was thought to be due to the inclusion of germline mutations, hereditary thrombocytosis. Accumulating the genetic and clinical characteristics of noncanonical mutations may help future clinical interventions in TN ET and hereditary thrombocytosis.

[Adult T-cell leukemia-lymphoma with severe hepatic damage and fluid retention successfully treated with mogamulizumab]

Adult T-cell leukemia-lymphoma (ATL) is a peripheral T-cell malignancy caused by the human T-cell lymphotropic virus, type I and it has an extremely poor prognosis. A 66-year-old man with severe hepatic damage, massive pleural effusion and ATL cell infiltration-induced ascites was referred to our department. Reduced-intensity cytotoxic chemotherapy was attempted, but could not continue due to persistent hyperbilirubinemia. Laboratory results also showed elevated lactate dehydrogenase (LDH) and serum albumin levels were profoundly decreased. A humanized monoclonal antibody against chemokine receptor type 4 (CCR4), mogamulizumab (Moga), was thereby challenged and it successfully resolved the hepatic damage. Finally, a standard dose of chemotherapy could be administered, and it induced a complete remission. The patient is still in remission more than three years after the final dosage of standard chemotherapy. These results indicate that Moga, whose pharmacokinetics are not significantly influenced by hepatic function or serum albumin, could be a promising treatment option for patients with ATL complicated by severe hepatic damage due to infiltration of ATL cells.

Development of a cascade arc discharge source for an atmosphere-vacuum interface device

To realize a novel vacuum-atmosphere interface that does not require a large differential pumping system, a robust cascade arc discharge source called a plasma window is constructed and tested for long-term operation. By modifying a test plasma with a direct current discharge, a vacuum interface with a high gas pressure ratio of 1/407 between the discharge and expansion sections is demonstrated for currents as high as 20 A. No significant damage to the electrodes is observed during the operation. Analysis of the visible emission spectra reveals that a stationary, stable argon plasma having a temperature of 1 eV and a density of 1.5 × 10(16) cm(-3) is generated in the plasma channel.

A new ATL xenograft model and evaluation of pyrrolidine dithiocarbamate as a potential ATL therapeutic agent

Adult T-cell leukemia/lymphoma (ATL) is caused by human T-lymphotrophic virus type 1 infection and is one of the most refractory malignant T-cell lymphomas. Improvement of ATL therapy options requires the establishment of appropriate ATL animal models. In this study, we successfully generated an ATL mouse model by xenotransplantation of primary peripheral blood mononuclear cells (PBMCs) isolated from ATL patients (ATL cells) into nonobese diabetic/severe combined immunodeficiency/Jak3-null mice (NOJ mice). To generate the model, the ATL S1T cell line was subcutaneously injected into mice. Primary ATL cells were then transplanted subcutaneously, intraperitoneally, or intravenously. ATL cells infiltrated multiple organs, and elevated human soluble interleukin 2 receptor (IL-2R) levels were detected in peripheral blood. Injection of one million primary ATL cells was needed for successful engraftment into host mice. Thawed cells, frozen long-term in liquid nitrogen, could also be transplanted; however, more cells were required to achieve similar results. The median mouse survival time was proportional to the number of cells injected. Successful secondary transplantation of ATL cells from one NOJ mouse into another was achieved and confirmed by T-cell receptor analysis. Finally, we examined the effects of the antioxide pyrrolidine dithiocarbamate (PDTC) as an antitumor agent in vivo. PDTC administration inhibited the increase of soluble IL-2R and improved mouse survival, suggesting that this compound has potential as an anti-ATL agent. We demonstrated that ATL cells could be stably xenotransplanted into NOJ mice using primary cells. This model will be useful in the establishment of novel therapies to treat ATL.

Origin of heterogeneity of interleukin-6 (IL-6) levels in malignant pleural effusions

We measured interleukin-6 (IL-6) concentrations from 48 malignant pleural effusions by an enzyme immunoassay and found a marked heterogeneity of the concentrations. The histological type of the malignant cells and total counts or differentials of the cells in effusions could not account for the heterogeneity. We newly established five malignant cell lines and found that the amounts of IL-6 produced by them were well correlated with IL-6 concentrations of the effusions from which these lines were derived (r=0.96; p<0.01). These results suggest that a marked heterogeneity of IL-6 concentrations in malignant effusions reflects the differential production of IL-6 by malignant cells in pleural space.

In vitro evaluation of dry powder inhaler devices of corticosteroid preparations

BACKGROUND

Although investigations of the drug aerosols generated from inhaled corticosteroid (ICS) preparations and combined drug preparations provide basic information about inhalation therapy, many clinicians have one-sided data about the precision of drug aerosols from the manufacturer. The present study was conducted to analyze and compare the performances of dry powder inhaler (DPI) devices of ICS and combined drug preparations.

METHODS

The particle size of individual aerosols was measured according to the time-of-flight principle in terms of their aerodynamic diameter by using the aerodynamic particle sizer spectrometer Model 3321. Percent aerosolization was measured using only stage #0 and backup filters of the Andersen non-viable sampler model AN-200.

RESULTS

The particle size distribution of aerosols generated from a Turbuhaler™ and Twisthaler™ showed a mono-modal distribution of less than 5 μm. In contrast, Diskus™ showed a polydisperse distribution, ranging from 0.5 to 20 μm. The percentages of DPI preparations converted into aerosols with a particle size less than 11 μm at a suction flow rate of 28.3 L/min were 5.7-6.2% for Diskus, 37.5-47.0% for Turbuhaler, and 19.8% for Twisthaler. At a suction flow rate of 60 L/min, the conversion percentages for DPI preparations into aerosols with a particle size less than 7.6 μm were 5.9-7.5%, 78.2-86.7%, and 43.5%, respectively.

CONCLUSIONS

Because in vitro differences in the aerosolization among different DPI devices containing ICS and combined drug preparations were observed, prescribers of these preparations should consider whether the patients will benefit more from the treatment of the central airways versus the peripheral airways.

Down-scattered neutron imaging detector for areal density measurement of inertial confinement fusion

A custom developed (6)Li glass scintillator (APLF80+3Pr) for down-scattered neutron diagnostics in inertial confinement fusion experiments is presented. (6)Li provides an enhanced sensitivity for down-scattered neutrons in DD fusion and its experimentally observed 5-6 ns response time fulfills the requirement for down-scattered neutron detectors. A time-of-flight detector operating in the current mode using the APLF80+3Pr was designed and its feasibility observing down-scattered neutrons was demonstrated. Furthermore, a prototype design for a down-scattered neutron imaging detector was also demonstrated. This material promises viability as a future down-scattered neutron detector for the National Ignition Facility.

[A study of drug aerosols generated by various devices for inhaled steroids]

PURPOSE

To evaluate the performances of various devices for inhaled steroid.

METHODS

Aerosol particle diameters were determined using the Aerodynamic Particle Sizer Spectrometer. Conversion ratios to fine particle aerosol were determined using an Andersen non-bubble sampler.

RESULTS

The mass median aerodynamic diameter was between 1 and 4 microm for all devices examined, tending to decrease with the increase in a suction flow rate. The percent of drug aerosolized less than 11 microm in diameter at a suction flow rate of 28.3 L/min was 100% for BDP-HFA and CIC-HFA, 87.5% for FP-HFA, 47.0% for BUD-DPI, 6.2% for FP-DPI, and 4.9% for SFC-DPI. The percent of drug aerosolized less than 7.6 microm in diameter at a suction flow rate of 60 L/min was 78.2% for BUD-DPI, 5.9% for FP-DPI, and 6.5% for SFC-DPI.

DISCUSSION

For MDI preparations, devices permitting easy synchronization of drug atomization and inspiration exhibited higher inhalation efficiency. For DPI preparations, the BUD-DPI device exhibited higher inhalation efficiency, which was enhanced by increasing the suction flow rate.

A phase II study of nedaplatin (CDGP) and docetaxel (TXT) in patients with advanced non-small cell lung cancer (NSCLC)

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Background: Nedaplatin (CDGP) is a cisplatin derivative developed in Japan. In non-small cell lung cancer (NSCLC), its response as monotherapy has been reported to be 20.5%, while when used in combination with vindesine, its efficacy is similar to cisplatin (CDDP). With respect to adverse effects, it causes less nausea/vomiting and nephrotoxicity compared to CDDP. By these data, we conducted a phase II study of combination treatment with CDGP and docetaxel (TXT) in advanced NSCLC. Methods: Forty six patients (Male/Female 39/7, median age 65 years (40–79), IIIB/IV 20/26) were enrolled from March 2004 to March 2006. Eligibility criteria included signed informed consent, age over 20 and under 80, measurable disease, ECOG PS 0–1, adequate bone marrow reserve, no previous chemotherapy or radiotherapy, and life-expectancy of at least 12 weeks. Treatment consisted of 80 mg/m2 CDGP and 60 mg/m2 TXT on day one with about 1,000 ml of hydration every 3–4 weeks. Results: One hundred and forty four cycles were given to 46 pts (mean cycles 3.1) and the mean dosages actually administered were 75.5±6.1 mg/m2 for CGDP and 57.7±4.6 mg/m2 for TXT. An over all response rate was 52.2% (squamous cell carcinoma 66.7%, adenocarcinoma 44.0%), median survival time was 12 months and 1-year survival rate was 50%. NCI-CTC grades 3–4 leukopenia, neutropenia, nausea/vomiting and appetite loss occurred in 44 (29.2%), 50 (34.7%), 5 (3.5%), 6 (4.2%) cycles, respectively. There was no grade 3–4 anemia, thrombocytopenia and neuropathy. Conclusions: This combination of chemotherapy was well tolerated, and its activity and survival for advanced NSCLC were acceptable. The update data will be presented at the meeting.

No significant financial relationships to disclose.