Lemongrass essential oil and citral inhibit Src/Stat3 activity and suppress the proliferation/survival of small-cell lung cancer cells, alone or in combination with chemotherapeutic agents.

Small-cell lung cancer (SCLC) is intractable due to its high propensity for relapse. Novel agents are thus needed for SCLC treatment. Lemongrass essential oil (LG-EO) and its major constituent, citral, have been reported to inhibit the proliferation and survival of several types of cancer cells. However, the precise mechanisms through which LG-EO and citral exert their effects on SCLC cells have not been fully elucidated. SCLC cells express Src and have high levels of Src-tyrosine kinase (Src-TK) activity. In most SCLC cell lines, constitutive phosphorylation of Stat3(Y705), which is essential for its activation, has been detected. Src-TK can phosphorylate Stat3(Y705), and activated Stat3 promotes the expression of the anti-apoptotic factors Bcl-xL and Mcl-1. In the present study, LG-EO and citral prevented Src-TK from phosphorylating Stat3(Y705), resulting in decreased Bcl-xL and Mcl-1 expression, in turn suppressing the proliferation/survival of SCLC cells. To confirm these findings, the wild-type-src gene was transfected into the LU135 SCLC cell line (LU135­wt-src), in which Src and activated phospho-Stat3(Y705) were overexpressed. The suppression of cell proliferation and the induction of apoptosis by treatment with LG-EO or citral were significantly attenuated in the LU135-wt-src cells compared with the control LU135-mock cells. The signal transducer and activator of transcription 3 (Stat3) signaling pathway is also associated with intrinsic drug resistance. LU135-wt-src cells were significantly resistant to conventional chemotherapeutic agents compared with LU135-mock cells. The combined effects of citral and each conventional chemotherapeutic agent on SCLC cells were also evaluated. The combination treatment exerted additive or more prominent effects on LU135-wt-src, LU165 and MN1112 cells, which are relatively chemoresistant SCLC cells. These findings suggest that either LG-EO or citral, alone or in combination with chemotherapeutic agents, may be a novel therapeutic option for SCLC patients.

Cbl negatively regulates erythropoietin-induced growth and survival signaling through the proteasomal degradation of Src kinase.

We examined the biological functions of the gene Cbl in erythropoietin (EPO) signaling using Cbl-deficient F-36P human erythroleukemia cells by the introduction of the Cbl siRNA expression vector. Knockdown of Cbl promoted EPO-dependent proliferation and survival of F-36P cells, especially at a low concentration of EPO (0.01U/mL), similar to serum concentrations of EPO in healthy volunteers (0.005-0.04U/mL). We found that Src was degraded mainly by the proteasomal pathway because the proteasome inhibitor MG-132 but not the lysosome inhibitor NH4Cl suppressed the EPO-induced degradation of Src in F-36P cells and that knockdown of Cbl inhibited EPO-induced ubiquitination and degradation of Src in F-36P cells. The experiments using the Src inhibitor PP1 and co-expression experiments further confirmed that Cbl and the kinase activity of Src are required for the EPO-induced ubiquitination of Src. In addition, the co-expression experiments and in vitro kinase assay demonstrated that the EPO-induced tyrosine phosphorylation and ubiquitination of Cbl were dependent on the kinase activity of Src but not Jak2. Thus, Cbl negatively regulates EPO signaling mainly through the proteasome-dependent degradation of Src, and the E3 ligase activity of Cbl and its tyrosine phosphorylation are regulated by Src but not Jak2.

Synchronous adenocarcinoma and follicular lymphoma of the stomach.

A 73-year-old Japanese man with synchronous follicular lymphoma and adenocarcinoma of the stomach underwent curative surgical resection. The follicular lymphoma lesion was preoperatively diagnosed as extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) according to biopsy samples. However, postoperative pathological evaluations revealed components of CD10-positive and CD10-negative lymphoma cells within the lymphoma lesion. This case highlights the potential difficulty of diagnosing gastric follicular lymphoma. In such cases, conducting repeat pathological examinations of biopsy samples or resected specimens is required to obtain a correct diagnosis of follicular lymphoma.

Primary follicular lymphoma of the duodenum with erosions as atypical macroscopic features.

A 52-year-old Japanese woman who was eventually diagnosed with primary follicular lymphoma of the duodenum showed atypical endoscopic features, namely, erosions with peripheral whitish edematous mucosa. Initial biopsy specimens taken from the erosions revealed insufficient numbers of lymphoma cells for histological diagnosis. Subsequent biopsy specimens from the peripheral mucosa containing the whitish enlarged villi showed infiltration of the lymphoma cells forming lymphoid follicles, which led us to the appropriate diagnosis. This case indicates that endoscopists should take biopsy samples from the peripheral mucosa with whitish enlarged villi rather than erosions in the rare instances that erosions appear as the main macroscopic feature of intestinal follicular lymphoma.

S-1 induced secondary acute erythroid leukemia with a chromosome inv(12)(p13;q13).

Adjuvant chemotherapy by S-1 following gastrectomy is considered standard treatment in Japan. Analysis of follow-up data have proved the efficacy of S-1 administration, and that hematological adverse events were relatively rare. Pyrimidine anti-metabolites, including S-1, have shown relatively lower risks for secondary hematological malignancies in comparison to alkylating agents and topoisomerase-II inhibitors. We here report a case of therapy-related leukemia after S-1 administration. A patient who had received S-1as the sole adjuvant chemotherapy was diagnosed with acute erythroid leukemia. To the best of our knowledge, our patient represents the first report of S-1 induced acute leukemia.

Expression of CD38 with intracellular enzymatic activity: a possible explanation for the insulin release induced by intracellular cADPR.

CD38 is a transmembrane glycoprotein expressed in multiple cell types, including pancreatic ß cells. It can serve as an enzyme that catalyzes the metabolism of two different Ca(2+)-mobilizing compounds, cyclic adenosine diphosphoribose (cADPR) and nicotinic acid adenine dinucleotide phosphate. One of these metabolites, cADPR, is known to be involved in glucose-induced insulin secretion from pancreatic ß cells. Although the essential role of CD38 for endogenous cADPR synthesis has been established, the relationship between the proposed extracellular enzymatic activity of CD38 and the intracellular Ca(2+) modulation caused by the intracellular cADPR accumulation has not yet been fully explained. For a better understanding of the role of CD38 in the insulin secretion machinery, analysis of the intracellular localization of this molecule in pancreatic ß cells is essential. In an attempt to provide a method to probe the N-terminal and C-terminal of CD38 separately, we generated an insulin-secreting MIN6 murine pancreatic ß cell line expressing a human CD38 bearing an N-terminal FLAG epitope tag. We found a weak but consistent expression of the FLAG epitope outside of the cells, indicating the presence of a small amount of CD38 with cytoplasmic enzymatic activity. MIN6 cells transfected with human CD38 exhibited increased glucose-induced insulin release. In addition, anti-FLAG cross-linking further enhanced the insulin release, suggesting that the N-terminal of CD38 expressed on the cell surface functions as a receptor for an unknown ligand and triggers positive signals for insulin secretion.

Medical cost analysis for antifungal prophylaxis in neutropenic patients with hematological malignancies: a systematic simulation analysis.

GOALS OF WORK: We assessed the medical costs of different antifungal agents for prophylaxis of invasive fungal infections in neutropenic patients in Japan with a cost simulation model designed for the study. PATIENTS AND METHODS: We used probabilities of prophylaxis failure, possible cases for empiric therapy, probable proportions of infections caused by fungus species among prophylaxis failure patients, and incidence of adverse events caused by any reason, based on systematic analysis of previously reported randomized trials identified by a computerized search of the PubMed database. Antifungal agents were limited to oral fluconazole, oral itraconazole, micafungin, and liposomal amphotericin B. The range of the expected medical cost was simulated as a sensitivity analysis using 95% of confidence interval of a mean. MAIN RESULTS: Fifteen studies were identified for our analysis. The prophylactic efficacy was comparable between the four agents. The simulated expected cost for invasive fungal infection prophylaxis and treatment of the infection was $1,035.74 when oral itraconazole was used for prophylaxis, $1,552.81 with oral fluconazole, $2,245.96 with micafungin, and $3,028.10 with liposomal amphotericin B. The total cost including treatment cost for adverse events related to each drug was $2,742.14, $3,547.91, $3,034.57, and $3,028.10, respectively. This result was confirmed in a sensitivity analysis in which IFI incidence and therapy duration were tested as parameters. CONCLUSIONS: Our analysis results suggest that oral itraconazole is the most cost-effective prophylactic antifungal agent for invasive fungal infections in neutropenic patients with hematological malignancies, and this result was robust by sensitivity analysis.

The immature platelet fraction is a useful marker for predicting the timing of platelet recovery in patients with cancer after chemotherapy and hematopoietic stem cell transplantation.

Prediction of the timing of platelet recovery after chemotherapy and hematopoietic stem cell transplantation (HSCT) allows for optimal platelet transfusion. We assessed the clinical utility of the percentage value of the immature platelet fraction (IPF%) monitored using an XE-2100 automated hematology analyzer to predict the timing of platelet recovery after chemotherapy and HSCT. The IPF% was serially monitored in 31 patients with cancer who received 66 courses of chemotherapy and HSCT. In patients with cancer undergoing chemotherapy and HSCT, a transient increase in IPF% was observed 1-11 days prior to platelet recovery (>30 × 109 /l). In patients undergoing chemotherapy with a peak IPF% >10%, platelet recovery occurred significantly earlier than in those with IPF% peak values ≤10% (median periods were 2 and 5 days; P < 0.05). Platelet recovery appears to occur earlier in patients undergoing HSCT with a peak IPF% >10% than in those with IPF% peak values ≤10% (median periods were 2 and 6 days). Thus, the IPF% peak value is a useful parameter for predicting the timing of platelet recovery after chemotherapy and HSCT and has the potential to facilitate optimal platelet transfusion.

Automated assay for determining cellular cholesterol using a random access chemistry analyser.

BACKGROUND: We have previously reported an ultrasensitive fluorometric assay for measuring cellular cholesterol. Although this technique is reliable, the use of the assay has limitations due to the requirement for special equipment. It is therefore difficult to apply this assay for the routine determination of cellular cholesterol. METHODS: A colorimetric assay to measure cellular cholesterol was established that utilizes reagents widely used for the measurement of cholesterol in blood samples in conjunction with a random access chemistry analyser ARCHITECT c8000 that is also common in clinical laboratories. RESULTS: This colorimetric assay showed excellent linearity and recovery. The within-run coefficients of variation were less than 2.5%. The sensitivity of this method, with its detection limit of 1.29 mumol/L, was found to be superior to that of the fluorometric assay we have developed previously. In platelets obtained from patients with diabetes, both the free cholesterol and cholesterol ester content were significantly increased. CONCLUSIONS: Using this technique, measurement of cellular cholesterol could be performed routinely without the requirement for special reagents and equipment.

Lineage switch from precursor B cell acute lymphoblastic leukemia to acute monocytic leukemia at relapse.

A lineage switch in leukemia, in which the leukemic cell lineage at onset converts to another lineage at a later time, is an uncommon type of hybrid (mixed) leukemia regarded as a variation of bilineage leukemia. We present a case of a 60-year-old female diagnosed with precursor B cell acute lymphoblastic leukemia (ALL), whose markers in flow cytometry shifted from their original status of CD19+, 22+, 79a+, 13+, HLA-DR+, and TdT+. Although her bone marrow achieved remission after induction therapy, there was a small residual population of leukemic cells in the liver. Residual disease was proved by biopsy and pathologically shown to have an immature phenotype of CD5+, CD10-, CD20-, CD79a- and myeloperoxidase negativity. Two weeks after liver biopsy, blast cells progressively appeared in the peripheral blood; these cells had a monocytoid morphology and phenotype (CD13, 14) but were accompanied by myeloid (CD33) and lymphoid (CD2, 4, 20) cells. Markers CD7, 10 and 19 were negative by flow cytometry. This phenotypical conversion from B-ALL to hybrid leukemia featuring monocytoid characteristics is known as a lineage switch. This case suggests that leukemic subclones tend to carry out dedifferentiation, occasionally in extramedullary sites, which serve as a hotbed for the selection of resistant clones.

Tec protein tyrosine kinase inhibits CD25 expression in human T-lymphocyte.

The Tec protein tyrosine kinase (PTK) belongs to a group of structurally related nonreceptor PTKs that also includes Btk, Itk, Rlk, and Bmx. Previous studies have suggested that these kinases play important roles in hematopoiesis and in the lymphocyte signaling pathway. Despite evidence suggesting the involvement of Tec in the T-lymphocyte activation pathway via T-cell receptor (TCR) and CD28, Tec's role in T-lymphocytes remains unclear because of the lack of apparent defects in T-lymphocyte function in Tec-deficient mice. In this study, we investigated the role of Tec in human T-lymphocyte using the Jurkat T-lymphoid cell line stably transfected with a cDNA encoding Tec. We found that the expression of wild-type Tec inhibited the expression of CD25 induced by TCR cross-linking. Second, we observed that LFM-A13, a selective inhibitor of Tec family PTK, rescued the suppression of TCR-induced CD25 expression observed in wild-type Tec-expressing Jurkat cells. In addition, expression of kinase-deleted Tec did not alter the expression level of CD25 after TCR ligation. We conclude that Tec PTK mediates signals that negatively regulate CD25 expression induced by TCR cross-linking. This, in turn, implies that this PTK plays a role in the attenuation of IL-2 activity in human T-lymphocytes.

Acute leukemia of ambiguous lineage, biphenotype, without CD34, TdT or TCR-rearrangement.

Biphenotypic acute leukemia (BAL) is a rare entity that comprises 0.5-3% of all acute leukemias and probably arises from multipotent progenitor cells. The optimal approach for BAL therapy is unknown. Thus, it is important to elucidate the origin of the neoplastic cells for determination of the appropriate therapy. We report the case of a 41-year-old man with BAL having myeloid and T-lymphoid lineage phenotypes. Strangely, neither CD34 nor TdT expression nor rearrangement of TCR-alpha/beta, delta/gamma genes were shown. This pattern is rarely encountered and suggests that the blast cells were possibly considered immature with aspects of differentiation indicating myeloid lineage, rather than T-lymphoid lineage.

Gab1 transduces PI3K-mediated erythropoietin signals to the Erk pathway and regulates erythropoietin-dependent proliferation and survival of erythroid cells.

In this study, we examined the biological functions of Gab1 in erythropoietin receptor (EPOR)-mediated signaling in vivo. Knockdown of Gab1 by the introduction of the Gab1 siRNA expression vector into F-36P human erythroleukemia (F-36P-Gab1-siRNA) cells resulted in a reduction of cell proliferation and survival in response to EPO. EPO-induced activation of Erk1/2 but not of Akt was significantly suppressed in F-36P-Gab1-siRNA cells compared with mock-transfected F-36P cells. The co-immunoprecipitation experiments revealed an EPO-enhanced association of Gab1 with the Grb2-SOS1 complex and SHP-2 in F-36P cells. A selective inhibitor of phosphatidylinositol 3-kinase (PI3K) LY294002 and short interfering RNA (siRNA) duplexes targeting the p85 regulatory subunit of PI3K (p85-siRNA) independently suppressed tyrosine phosphorylation of Gab1; its association with Grb2, SHP-2 and p85; and the activation of Erk in EPO-treated F-36P cells. LY294002 inhibited EPO-induced tyrosine phosphorylation of Gab1 and its association with Grb2 in human primary EPO-sensitive erythroid cells. The co-immunoprecipitation experiments using the Jak inhibitor AG490 or siRNA duplexes targeting Jak2 and in vitro binding experiments demonstrated that Jak2 regulated Gab1-mediated Erk activation through tyrosine phosphorylation of Gab1. Taken together, these results suggest that Gab1 couples PI3K-mediated EPO signals with the Ras/Erk pathway and that Gab1 plays an important role in EPOR-mediated signal transduction involved in the proliferation and survival of erythroid cells.

Fludarabine and melphalan conditioning with tacrolimus as GVHD prophylaxis for allogeneic stem cell transplant recipients is an effective reduced-intensity combination regimen compared to the conventional regimen.

BACKGROUND: As a reduced-intensity stem-cell transplantation (RIST) regimen, the combination of fludarabine and melphalan (FM) with an appropriate immunosuppressant reduces nonrelapse mortality (NRM). METHODS: We retrospectively compared the efficacy of a RIST regimen with FM with that of a conventional stem cell transplantation (CST) regimen. Eighty-two consecutive hematological patients who underwent allogeneic stem-cell transplantation (SCT) at our hospital were enrolled. Preparation for RIST consisted of 25 mg/m(2) fludarabine and melphalan 70 mg/m(2). The conventional regimen employed high-dose cyclophosphamide and total-body irradiation (12 Gy) or busulfan and high-dose cyclophosphamide. Graft-versus-host disease (GVHD) prophylaxis for RIST consisted of tacrolimus alone or in conjunction with short-term methotrexate for unrelated donors. RESULTS: Of the 82 patients, 42 received the conventional CST regimen (median age, 35 years) and 40 received the RIST regimen (median age, 51 years). The probability of NRM was 17% (7/42) in the CST group and 8% (3/40) in the RIST group. Grade II to IV GVHD occurred in significantly more CST patients (38%) than RIST patients (28%). However, the overall survival was the same in the two groups (43%). CONCLUSION: The RIST regimen with FM incorporating tacrolimus and methotrexate demonstrated low TRM incidence and moderate control of GVHD and had efficacy comparable to that of the CST regimen, despite the advanced age of the RIST patient group.

Usefulness of immature platelet fraction for the clinical evaluation of myelodysplastic syndromes.

Ratios of young platelets or reticulated platelets can be routinely obtained as an immature platelet fraction (IPF) with the XE-2100 automated hematology analyzer (Sysmex, Kobe, Japan). We combined IPF analysis of 31 patients with myelodysplastic syndrome (MDS) with a complete blood count, a bone marrow examination, and a chromosome analysis. The patients with >40 x 10(9)/L platelets were classified as group A, and those with > or =40 x 10(9)/L were placed in group B. The 2 groups were subclassified as A1 or B1 for patients with an IPF of <10% and as A2 or B2 for those with an IPF > or =10%. Categories A1, A2, B1, and B2 comprised 12 patients, 6 patients, 7 patients, and 6 patients, respectively. Patients with a relatively high IPF (>10%) (category A2 or B2) showed distinctive characteristics. Group B2 showed a higher frequency of chromosomal abnormalities than B1 (P = .029), and group A2 tended to show a higher incidence of clinical improvement than A1 (P = .08). IPF determination may be clinically useful for the assessment of prognosis for MDS patients.

[Long-term remission of non-Hodgkin lymphoma secondary to the treatment for essential thrombocythemia].

A 45-year-old woman was diagnosed with essential thrombocythemia (ET) in August 1987 and received treatment with alkylating agents (total administration dose, busulfan 378 mg, MCNU 700 mg) because of a history of myocardial infarction. In June 2000, anemia gradually progressed. A few blast cells were detected in the peripheral blood at that time. Since bone marrow biopsy revealed myelofibrosis, she received anabolic hormone therapy. She was admitted to our hospital for an evaluation of abdominal distension in February 2003. Swelling of a large paraaortic lymph node of 6 cm in diameter was detected by CT scan. Lymph node biopsy revealed diffuse large B-cell lymphoma. Lymphoma cells were positive for CD10, CD19, CD20 and kappa-chain. The clinical stage was I. Complete remission has been achieved for 57 months after treatment with combination chemotherapy combined with rituximab followed by local radiation therapy. Non-Hodgkin lymphoma secondary to ET is a rare event. Such cases should therefore be accumulated to evaluate the mechanism of onset and clinical characteristics of lymphoma secondary to ET.

Intravascular large B-cell lymphoma with FDG accumulation in the lung lacking CT/(67)gallium scintigraphy abnormality.

Intravascular large B-cell lymphoma (IVLBCL) is a rare lymphoma characterized by the presence of large tumour cells within the blood vessels. It has been considered that IVLBCL is a highly malignant disease with poor prognosis. However, it has been shown that a therapeutic effect resembling that of conventional B-cell lymphomas may be obtained with the application of systemic chemotherapy at the early stage of this disease. Although involvement in the lung is often detected at autopsy, early diagnosis is quite difficult. In this report, we present a case of IVLBCL with pulmonary involvement where 18-fluoro-deoxyglucose positron emission tomography (FDG-PET) was useful in the early diagnosis. Neither computed tomography (CT) nor (67)gallium scintigraphy could reveal the presence of disease in the lung. Histological evidence of IVLBCL was obtained by TBLB after FDG uptake in the lung was confirmed by FDG-PET. The patient exhibited a good response to the subsequent combination chemotherapy. We propose that FDG-PET is a powerful tool for the early diagnosis of IVLBCL with pulmonary involvement, if the possibility of this disease presents in the patient with respiratory symptoms without abnormal findings by CT and (67)gallium scintigraphy.

Pancytopenia complicated with peripheral neuropathy due to copper deficiency: clinical diagnostic review.

Only a dozen cases of pancytopenia caused by copper deficiency have been reported. We report the case of an 81-year-old man who underwent total gastrectomy for gastric cancer. He received total parenteral nutrition without trace element supplementation for 6 months. Serum levels of copper and ceruloplasmin were low, but serum zinc was normal. The administration of copper into TPN led to rapid improvement in anemia and neutropenia. We review 11 previous cases of copper-deficient cytopenia, categorized into two groups according to etiology, and define the characteristic symptom of copper malabsorption caused by excess Zn as peripheral neuropathy.