Chikashi Yoshida

Long range interaction of cis‐DNA elements mediated by architectural transcription factor Bach1

A central question in vertebrate transcriptional regulation is how cis‐regulatory modules, including enhancers, silencers and promoters, communicate with each other over long distances to mandate proper gene expression. In order to address this question we analysed protein/DNA interactions in the human β‐globin locus control region (LCR). One of the many proteins that are potentially implicated in LCR function is Bach1. Bach1 possesses a basic leucine zipper (bZip) domain, as well as a BTB/POZ domain that has been shown to be involved in the regulation of chromatin structure. Bach1 forms heterodimers with small Maf proteins through its leucine zipper and binds to Maf recognition elements (MARE).

Shorter halving time of BCR-ABL1 transcripts is a novel predictor for achievement of molecular responses in newly diagnosed chronic-phase chronic myeloid leukemia treated with dasatinib: Results of the D-first study of Kanto CML study group

To investigate the factors that affect molecular responses on dasatinib treatment in patients with chronic‐phase chronic myeloid leukemia (CML‐CP), we performed a clinical trial named the “D‐First study.” Fifty‐two patients with newly diagnosed CML‐CP were enrolled in this study and received 100 mg dasatinib once daily. A deep molecular response (DMR) was defined as <50 copies/μg RNA of BCR‐ABL1 transcript value corrected by GAPDH, which ensures <0.01% of BCR‐ABL1 transcript value according to International Scale (BCR‐ABL1IS). The halving time for BCR‐ABL1 transcripts was calculated using transcript levels before dasatinib treatment, transcript levels after 3 months of treatment, and the treatment time between these two points. In terms of molecular response, 38 of 51 (75%) patients reached major molecular response (MMR) by 12 months, and the rate of DMR by 18 months was 59% (30/51). While both BCR‐ABL1 transcript levels before treatment and a shorter halving time of BCR‐ABL1 transcripts (≤14 days) were significant factors affecting achievement of MMR by 12 months, the Sokal score at diagnosis was not associated with MMR. Importantly, the halving time was the only factor that predicted achievement of DMR by 18 months. We showed that patients with CML‐CP treated with dasatinib can be stratified according to the early treatment response as determined by the halving time of BCR‐ABL1 transcripts. These data emphasize the significance of the early response from dasatinib treatment in achieving a DMR. (ClinicalTrials.gov; NCT01464411) Am. J. Hematol. 90:282–287, 2015.

Adherence to the standard dose of imatinib, rather than dose adjustment based on its plasma concentration, is critical to achieve a deep molecular response in patients with chronic myeloid leukemia

The correlation between imatinib (IM) trough plasma concentration (Cmin) and clinical response was assessed in patients with chronic-phase chronic myeloid leukemia. The Cmin correlated with neither the achievement of complete cytogenetic response (977 vs. 993 ng/ml, P = 0.48) nor a major molecular response (1,044 vs. 818 ng/ml, P = 0.17). Although this was significantly higher in patients with complete molecular response (CMR) than in those without (1,430 vs. 859 ng/ml, P = 0.04), the difference was not significant in the sub-population treated with a standard dose of IM (400 mg/day). Finally, multivariate analysis showed that the IM standard dose, but not Cmin, was predictive of the achievement of CMR. We thus suggest that, in practical clinics at least, adherence to the standard dose is the most important factor for the achievement of CMR.

Association of pyoderma gangrenosum and sterile osteomyelitis in a patient having myelodysplastic syndrome with der(1;7)(q10;q10)

Neutrophilic dermatoses such as Sweets disease and pyoderma gangrenosum (PG) are occasionally associated with myelodysplastic syndrome (MDS). We present here a 67‐yr‐old male having PG and sterile osteomyelitis in association with underlying MDS (refractory anemia) and Crohns disease. To establish the diagnosis of MDS, sternal bone marrow puncture was performed, which showed chromosomal abnormality containing der(1;7)(q10;q10). After the puncture, he suffered from gradually progressive skin ulceration, flare, and bone pain. Magnetic resonance imaging (MRI) of the sternum showed severe inflammation in the sternum and the overlying subcutaneous tissue. All of the cultures obtained from the wound were negative for both bacteria and fungus. Biopsy was performed from the antero‐sternal skin lesion, which showed epidermal ulceration with prominent infiltration of neutrophils. He was thus diagnosed as having PG and sterile osteomyelitis, and was treated with prednisolone, which completely resolved the symptoms. We consider that the bone marrow aspiration in the present patient provoked PG and sterile osteomyelitis. As was previously reported by others, certain chromosomal abnormalities in MDS may be related with the development of neutrophilic dermatoses.

Early cytotoxic lymphocyte expansion contributes to a deep molecular response to dasatinib in patients with newly diagnosed chronic myeloid leukemia in the chronic phase: results of the D-first study.

Dasatinib is one of the key treatment options for chronic myeloid leukemia (CML) patients. Increase in lymphocyte counts has been known to be predictive of a good treatment response under dasatinib treatment as a second line therapy. However, clinical significance of lymphocyte dynamics in the upfront setting has yet to be clarified. To investigate the significance of lymphocyte dynamics in newly diagnosed chronic phase (CP)‐CML, patient data of D‐First study (ClinicalTrials.gov NCT01464411) were analyzed. Fifty‐two CML‐CP patients enrolled to this study were treated with dasatinib (100 mg day−1) and all were followed‐up for 18 months. The incidence of lymphocyosis was observed in 14 (27%), but it was not associated with deep molecular response achievement. However, natural killer (NK) cell or cytotoxic T lymphocyte (CTL) counts at 1 month were significantly higher in patients with deep molecular response (DMR) by 18 months compared to those without DMR. When the patients were divided into two groups according to those calculated thresholds by receiver operating characteristic curve (407/μL for NK cells and 347/μL for CTLs), the cumulative DMR rates by 18 months were significantly better in higher value group compared to lower value group. In contrast, regulatory T cell counts were significantly lower at 12 and 15 months in patients achieved DMR. These results suggest the presence of dual effects of dasatinib on immune system through the cytotoxic lymphocytes activation and Treg deregulation in different periods in newly diagnosed CML‐CP. Am. J. Hematol. 90:819–824, 2015.

Cytotoxic T-cell lymphoma arising in Behçet disease.

The case of a 49-year-old man with peripheral T-cell lymphoma arising in Behçet disease (BD) is reported. A diagnosis of incomplete BD was made, and the patient was treated with immunosuppressive agents for 9 months. A left perirenal mass emerged, and a computed tomography-guided needle biopsy of the tumor revealed the infiltration of small- and medium-sized lymphoma cells.The cells were positive for CD3, CD8, CD45RO, CD43, granzyme B, and T-cell intracellular antigen-1.A diagnosis of non-Hodgkin’s lymphoma (diffuse medium, T-cell) was made.A left orbital mass also appeared. Standard combination chemotherapy diminished the perirenal and orbital lesions.Lymphoma cell infiltration in the esophagus was detected after chemotherapy, and the patient died of massive bleeding from the gastrointestinal tract. Non-Hodgkin’s lymphoma is rarely associated with BD, and only 7 cases have been reported in the literature.We have summarized the published case reports of malignant lymphoma arising in BD.To our knowledge, this case report is the first to describe cytotoxic T-cell lymphoma arising in Behçet disease.

Association of non-alcoholic steatohepatitis (NASH) with chronic neutrophilic leukemia.

A 54‐yr‐old female having chronic neutrophilic leukemia (CNL) associated with severe liver injury is presented. Physical examination on admission showed severe jaundice, hepatosplenomegaly, massive ascites, and pretibial edema. Complete blood count showed a hemoglobin level of 9.1 g/dL, platelet count of 25.8 × 104/μL, and white blood cell count of 36.6 × 103/μL with 89.7% neutrophils. Blood chemistry showed hyperbilirubinemia (21.9 mg/dL) with normal transaminase levels. There was no abnormality in serum cholesterol, triglyceride, or glucose levels. Neutrophil alkaline phosphatase activity was significantly elevated. Bone marrow aspiration showed myeloid hyperplasia with normal karyotype. Rearrangement of the bcr/abl was not detected by either polymerase chain reaction or fluorescence in situ hybridization. Human androgen receptor gene assay (HUMARA) of the bone marrow cells showed clonal proliferation of neutrophils. The patient was diagnosed as having CNL. To evaluate the pathogenesis of the liver injury, a needle biopsy was performed, which showed steatohepatitis with infiltration of neutrophils. As the patient had no history of alcohol abuse, a diagnosis of non‐alcoholic steatohepatitis (NASH) was made. Assuming that the infiltration of abnormal neutrophils into the liver contributed to the development of NASH, she was treated with cytoreductive chemotherapy (cytosine arabinoside: 100 mg/d, 1–3 doses/wk). With decreases in white blood cell counts, serum bilirubin levels decreased gradually to 1.5 mg/mL. A postchemotherapy liver biopsy specimen showed marked improvement of the fatty degenerative change. To our knowledge, this is the first report describing the development of NASH in a myeloproliferative disorder. We believe that the infiltration of leukemic cells contributed to the development of NASH in this patient.

Rapidly Progressive Lennert's Lymphoma Terminating in Fulminant Hepatic Failure

A 65-year-old male with rapidly progressive Lennerts lymphoma terminating in fulminant hepatic failure is presented. Staging radiological studies revealed that he had cervical and mediastinal lymph node swellings and multiple nodular lesions in the spleen. Lymph node biopsy specimens showed the proliferation of epithelioid cells interspersed with large blastic lymphocytes. These lymphocytes were CD3+, CD45RO (UCHL-1)+, CD4-, CD8+, CD56-, CD30-, CD15-, T-cell intracellular antigen-1+, granzyme B+ and perforin+, suggestive of the cytotoxic T-cell lineage. Under the diagnosis of Lennerts lymphoma, he was treated with standard CHOP chemotherapy. After two courses of the chemotherapy, despite the decreased size of cervical lymph nodes, high-grade fever and constitutional symptoms appeared. As multiple low-density nodules were observed in the liver by computed tomography, needle biopsy was performed. The biopsy specimens showed the proliferation of CD3+, CD4- and CD8+ lymphoma cells. Thereafter, the liver function deteriorated rapidly, and disseminated intravascular coagulation emerged. He died of rapidly progressive hepatic failure. This case is another example demonstrating that at least some of the Lennerts lymphomas phenotypically correspond with cytotoxic T-cell lymphomas, as was previously suggested by us [Am. J. Surg. Pathol24 (2000) 1627]. It should be also emphasized that Lennerts lymphomas containing cytotoxic proteins may have a fulminant clinical course, which cannot be rescued by the conventional chemotherapy.

Measurement of Proteasome Activity in Peripheral Blood Mononuclear Cells as an Indicator of Susceptibility to Bortezomib-Induced Severe Neurological Adverse Events in Patients with Multiple Myeloma

Aims: To explore the biomarker for predicting the occurrence of adverse events in myeloma patients treated by intravenous bortezomib, we measured proteasome activity in peripheral blood mononuclear cells. Methods: Samples were obtained from 34 bortezomib-naïve patients. Proteasome activity was measured at pre- and postchemotherapy phase by using a synthetic substrate. Results: Bortezomib injection resulted in a dramatic decrease in proteasome activity, reaching 32.4 ± 18.79% (mean ± SD) of the pretreatment level at 1 h, but it generally recovered at the end of the first course. In total, 6 patients manifested with severe bortezomib-induced peripheral neuropathy (sBIPN) in the second-third course. There was a nonsignificant trend for these patients to have lower levels of the relative proteasome activity at the end of the first course than those without sBIPN (median: 74.03 vs. 103.2%, p = 0.052). Moreover, in all of them, proteasome activity did not recover to the pretreatment level, whereas no patients with complete recovery manifested with sBIPN. Analysis with Fishers exact test demonstrated that incomplete recovery of proteasome activity is a significant risk factor for sBIPN (p = 0.014). Conclusion: Patients with incomplete recovery of proteasome activity are at high risk for developing sBIPN, and the susceptible patients can be indicated by monitoring proteasome activity.

Regulatory T cell inhibition by dasatinib is associated with natural killer cell differentiation and a favorable molecular response—The final results of the D-first study

We evaluated the effects of regulatory T cell (Treg) inhibition during dasatinib treatment on the anticancer immune response, particularly on natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). Fifty-two newly diagnosed Japanese patients with chronic myeloid leukemia (CML) in the chronic phase were enrolled in the D-first study; all received 100 mg of dasatinib once daily and were followed for at least 36 months. The cumulative deep molecular response (DMR, MR4) rate was 65% by 36 months; the 3-year overall survival was 96%. CD4+ T cell counts were stable, whereas the proportion of CD4+CD25+CD127low (Treg) cells decreased in a time-dependent manner. The DMR rate by18 months was significantly better in low Treg patients (<5.7% at 12 months) compared to the remaining patients (odds ratio 4.07). NK cell and CTL counts at several time points were inversely correlated with Treg counts. Furthermore, the degree of NK cell differentiation (CD3-CD57+/CD3-CD56+) was closely and inversely correlated with the proportion of Treg cells throughout the observation period, and showed a gradually increasing trend. In conclusion, our results demonstrate that Treg inhibition by dasatinib contributes to better treatment response through enhancement of the immune system, particularly via NK cell differentiation.