The magnitude of CXCR4 signaling regulates resistance to quizartinib in FLT3/ITD+ cells via RUNX1.

CXCR4 antagonists sensitize FLT3/ITD+ AML cells to FLT3 inhibitors; however, CXCR4 signaling can induce apoptosis in AML cells, raising the question of whether CXCR4 signaling exerts divergent effects on FLT3/ITD+ cells. The present study investigated the paradoxical function of CXCR4 in resistance to FLT3 inhibitors. The FLT3 inhibitor quizartinib significantly decreased the number of FLT3/ITD+ Ba/F3 cells, whereas 1 ng/ml CXCL12 showed a significant protective effect against quizartinib. In contrast, CXCL12 over 100 ng/ml significantly decreased FLT3/ITD+ cell viability with concomitant downregulation of Runx1. Moreover, the survival of FLT3/ITD+ Ba/F3 or MOLM13 cells with low surface CXCR4 expression incubated with quizartinib was significantly enhanced by 100 ng/ml CXCL12; however, this protective effect of CXCL12 against quizartinib was barely detected in cells with high surface CXCR4 expression. Although silencing Runx1 downregulated CXCR4 expression, RUNX1 expression levels were significantly higher in CXCR4LOW FLT3/ITD+ Ba/F3 cells incubated with 100 ng/ml CXCL12 than in CXCR4HIGH cells, coincident with an increase in FLT3 phosphorylation. Silencing RUNX1 partially abrogated resistance to quizartinib in CXCR4LOW cells incubated with CXCL12, whereas ectopic RUNX1 significantly restored resistance in CXCR4HIGH cells. These results indicate that CXCR4 signaling of different magnitudes paradoxically regulates resistance to quizartinib in FLT3/ITD+ cells via RUNX1.

Lymphoma during pregnancy in Japan: a multicenter retrospective cohort study.

OBJECTIVE: This study was conducted to characterize lymphoma occurring during pregnancy and to investigate the outcomes of the patients and the fetuses. METHODS: Clinical data were gathered retrospectively from 29 patients at 13 participating institutions, and data from 28 eligible patients were analyzed. RESULTS: Six (21%) patients had Hodgkin lymphoma (HL) and 22 (79%) patients had non-Hodgkin lymphoma (NHL). All patients with HL presented with lymphadenopathy, but 15 (68%) of the 22 patients with NHL presented with extranodal sites only. At the median follow-up period of 1325 (range 6-4461) days, the 5-year overall survival rate was 63% for patients with NHL and 100% for patients with HL. Three of the 13 patients who received chemotherapy during pregnancy (23%) developed Pneumocystis jiroveci pneumonia (PCP). There was 1 intrauterine fetal death, 1 spontaneous abortion in the first trimester, and 15 (54%) preterm births. CONCLUSION: This study showed a higher proportion of NHL than HL during pregnancy in Japan, which was inconsistent with the proportions observed in Western countries. The high incidence of maternal PCP and preterm birth suggested the need for improvements in our management of lymphoma during pregnancy.

Differential gene expression analysis of dasatinib-induced colitis in a patient with chronic myeloid leukemia followed for 3 years: a case report.

BACKGROUND: Dasatinib is a second-generation tyrosine kinase inhibitor (TKI) developed for treatment of patients with chronic myeloid leukemia (CML). The drug has been shown to act as a potent multikinase inhibitor by blocking not only the BCR-ABL1 gene sequence but also the SRC kinase family, though unexpected adverse events such as pleural effusion have recently been reported in patients undergoing treatment with dasatinib. Hemorrhagic colitis is a unique gastrointestinal adverse events associated with dasatinib and its pathogenesis remains poorly understood. CASE PRESENTATION: We report here a case of dasatinib-induced asymptomatic colitis in a patient with CML, who showed no exacerbation in careful observations and maintained deep molecular response (DMR) during a 3-year period. In addition, we performed transcriptome analysis of inflamed colonic mucosa specimens to clarify the possible mechanism of colitis that develops in association with dasatinib administration. Our results demonstrated that differential gene expression, especially lymphocyte-associated genes and chemokines, is substantially involved in inflammation of colonic mucosa in affected patients. CONCLUSION: Dasatinib induces immune-mediated colitis following lymphocyte infiltration.

[Cooperation between Clinics and Hospitals Using a Critical Path for G-CSF Prophylaxis in Cancer Chemotherapy].

BACKGROUND: Prophylactic granulocyte-colony stimulating factor(G-CSF)is necessary for some cancer patients receiving anti-cancer drugs. However, it is difficult for cancer patients in rural areas to receive G-CSF as outpatients because of inconvenient official transport, lack of public support, and low activity levels due to age. To resolve this problem, we began conducting a critical path(G-path)with regional medical institutions from 2011. METHODS: We retrospectively surveyed the clinical records of cancer patients receiving prophylactic G-CSF using G-path at our hospital. RESULTS: Eighty-two patients who were administered a total of 254 cycles of chemotherapy were examined between January 2011 and December 2016. Diseases included malignant lymphoma(n=64), pancreatic cancer(n=7), soft tissue sarcoma(n=5), and others(n=6). The median age of the patients was 70(range: 24-94)years. Fifty-three patients visited medical offices, and 31 patients visited regional hospitals. In 245 of 254(96%)cycles, planned G-CSF administration was performed. In 37 of 254(15%)cycles, infectious episodes developed, but patients needed hospitalization for only 5 cycles(2%). CONCLUSION: Cooperation between clinics and hospitals using G-path reduced ambulatory burden and prevented severe infection. Cooperation in supportive care may allow for equal accessibility to cancer treatment.

A prospective study of palonosetron for prevention of chemotherapy-induced nausea and vomiting in malignant lymphoma patients following highly emetogenic chemotherapy.

BACKGROUND: Chemotherapy-induced nausea and vomiting (CINV) is a troublesome issue in chemotherapy for cancer patients. A second-generation 5HT3 receptor antagonist (5HT3RA), palonosetron, is effective and safe for the prevention of CINV in breast cancer patients treated with cyclophosphamide and anthracycline, but there is little data for malignant lymphoma. We conducted a prospective phase 2 study at a single institution to clarify the efficacy and safety of palonosetron in lymphoma patients. METHODS: Chemotherapy-naïve lymphoma patients who were treated with highly emetogenic chemotherapy (HEC) received a single intravenous bolus of palonosetron, 0.75 mg/body, before chemotherapy on day 1 during the first course of chemotherapy. The occurrence of CINV was assessed using the Multinational Association for Supportive Care in Cancer (MASCC) antiemesis tool, which was recorded by patients during the first course of chemotherapy. RESULTS: A total of 59 patients were enrolled, and 49 patients were eligible and evaluated. The complete response (CR) rate was 93.9% (95% confidence interval 83.1-98.7%) at 0-120 h post-chemotherapy. The proportion of patients who developed nausea of any grade and vomiting at 0-120 h post-chemotherapy was 34.7 and 6.1%, respectively. Although treatment-related adverse events were observed in 36 (73.5%) patients, these were mild and they recovered by the next cycle of chemotherapy. CONCLUSION: The present study demonstrated that a single dose of palonosetron was highly effective and safe for the prevention of CINV in lymphoma patients.

Internal Tandem Duplication in FLT3 Attenuates Proliferation and Regulates Resistance to the FLT3 Inhibitor AC220 by Modulating p21Cdkn1a and Pbx1 in Hematopoietic Cells.

Internal tandem duplication (ITD) mutations in the Fms-related tyrosine kinase 3 (FLT3) gene (FLT3-ITD) are associated with poor prognosis in patients with acute myeloid leukemia (AML). Due to the development of drug resistance, few FLT3-ITD inhibitors are effective against FLT3-ITD+ AML. In this study, we show that FLT3-ITD activates a novel pathway involving p21Cdkn1a (p21) and pre-B cell leukemia transcription factor 1 (Pbx1) that attenuates FLT3-ITD cell proliferation and is involved in the development of drug resistance. FLT3-ITD up-regulated p21 expression in both mouse bone marrow c-kit+-Sca-1+-Lin- (KSL) cells and Ba/F3 cells. The loss of p21 expression enhanced growth factor-independent proliferation and sensitivity to cytarabine as a consequence of concomitantly enriching the S+G2/M phase population and significantly increasing the expression of Pbx1, but not Evi-1, in FLT3-ITD+ cells. This enhanced cell proliferation following the loss of p21 was partially abrogated when Pbx1 expression was silenced in FLT3-ITD+ primary bone marrow colony-forming cells and Ba/F3 cells. When FLT3-ITD was antagonized with AC220, a selective inhibitor of FLT3-ITD, p21 expression was decreased coincident with Pbx1 mRNA up-regulation and a rapid decline in the number of viable FLT3-ITD+ Ba/F3 cells; however, the cells eventually became refractory to AC220. Overexpressing p21 in FLT3-ITD+ Ba/F3 cells delayed the emergence of cells that were refractory to AC220, whereas p21 silencing accelerated their development. These data indicate that FLT3-ITD is capable of inhibiting FLT3-ITD+ cell proliferation through the p21/Pbx1 axis and that treatments that antagonize FLT3-ITD contribute to the subsequent development of cells that are refractory to a FLT3-ITD inhibitor by disrupting p21 expression.

A retrospective study of R-CHOP/CHOP therapy-induced nausea and vomiting in non-Hodgkin's lymphoma patients: a comparison of intravenous and oral 5-HT3 receptor antagonists.

Chemotherapy-induced nausea and vomiting (CINV) is a serious problem for cancer patients receiving chemotherapy. The CHOP regimen is the standard treatment for non-Hodgkin's lymphoma (NHL) and is categorized as highly or moderately emetogenic in the CINV guidelines. The efficacy of oral 5-HT3 receptor antagonists is equivalent to that of the intravenous form in patients with solid tumors, but there is no clear comparative data for the use of these agents NHL patients receiving CHOP. We analyzed retrospective CINV data from medical records of 72 NHL patients who received CHOP or rituximab-combined CHOP therapy (R-CHOP). All patients received 5-HT3 receptor antagonists alone for prevention of CINV; 39 of the patients received an intravenous form (mostly granisetron) and 33 an oral form (all ramosetron). Complete response (CR: defined as no vomiting and no rescue therapy) was observed in 58 of 72 patients (80.6 %) overall (0-120 h post-CHOP). The CR rate was not statistically different in patients treated with oral or intravenous 5-HT3 receptor antagonists (82.1 vs 78.8 %, P = 0.77). These findings suggest that oral 5-HT3 receptor antagonists represent a good alternative to intravenous forms in NHL receiving CHOP/R-CHOP chemotherapy. Further studies are needed to identify the optimal anti-emetic supportive therapy for NHL.

Internal tandem duplication of FLT3 deregulates proliferation and differentiation and confers resistance to the FLT3 inhibitor AC220 by Up-regulating RUNX1 expression in hematopoietic cells.

Internal tandem duplication in the FLT3 gene (FLT3/ITD), which is found in patients with acute myeloid leukemia (AML), causes resistance to FLT3 inhibitors. We found that RUNX1, a transcription factor that regulates normal hematopoiesis, is up-regulated in patients with FLT3/ITD(+) AML. While RUNX1 can function as a tumor suppressor, recent data have shown that RUNX1 is required for AML cell survival. In the present study, we investigated the functional role of RUNX1 in FLT3/ITD signaling. FLT3/ITD induced growth factor-independent proliferation and impaired G-CSF mediated myeloid differentiation in 32D hematopoietic cells, coincident with up-regulation of RUNX1 expression. Silencing of RUNX1 expression significantly decreased proliferation and secondary colony formation, and partially abrogated the impaired myeloid differentiation of FLT3/ITD(+) 32D cells. Although the number of FLT3/ITD(+) 32D cells declined after incubation with the FLT3/ITD inhibitor AC220, the cells became refractory to AC220, concomitant with up-regulation of RUNX1. Silencing of RUNX1 abrogated the emergence and proliferation of AC220-resistant FLT3/ITD(+) 32D cells in the presence of AC220. Our data indicate that FLT3/ITD deregulates cell proliferation and differentiation and confers resistance to AC220 by up-regulating RUNX1 expression. These findings suggest an oncogenic role for RUNX1 in FLT3/ITD(+) cells and that inhibition of RUNX1 function represents a potential therapeutic strategy in patients with refractory FLT3/ITD(+) AML.

Validity of the chemotherapy-induced peripheral neuropathy self-check sheet.

Objective Chemotherapy-induced peripheral neuropathy (CIPN) is a major dose-limiting side effect of some anti-cancer drugs. However, medical staff frequently encounter difficulties in ascertaining the severity of CIPN. We sought to develop a questionnaire in order to accurately assess CIPN. The validity of this questionnaire was compared with that of free-style interviews. Methods We developed the CIPN self-check sheet by analyzing existing self-assessment tools for CIPN and matching the National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) grades. From August to December 2011, 77 cancer patients participated in this study. In order to evaluate the validity of the CIPN self-check sheet compared with a free-style interview assessment, the cross-classification and κ coefficients between the CTCAE grades from each assessment and those from a comprehensive assessment were analyzed. The comprehensive assessment utilized information obtained from the medical examination, free-style interview and CIPN self-check sheet. Results Upon completion of the study, 248 CIPN self-check sheets were collected (median number of sheets per patient, 3; range, 1-14). The cross-classification analysis illustrated that the CIPN self-check sheet successfully identified all grade 3 cases. The coefficient of the CIPN self-check sheet was significantly higher than that of the free-style interviews [κ values: 0.988 (p<0.01) and 0.501 (p<0.01) for the self-check sheet and interviews, respectively]. Conclusion The CIPN self-check sheet can be used to assess the severity of CIPN based on the CTCAE grade more accurately than free-style interviews.

Synergistic combination therapy with cotylenin A and vincristine in multiple myeloma models.

Multiple myeloma is a malignant proliferative disease of plasma cells in the bone marrow and remains largely incurable. Cotylenin A, a fusicoccane diterpene glycoside with a complex sugar moiety, was isolated as a plant-growth regulator. Cotylenin A has been shown to inhibit the growth of various cancer cells. Herein, we examined the anti-myeloma effects of cotylenin A using five human myeloma cell lines (RPMI-8226, KMS-11, KMS-26, KMS-12 PE and KMS-12 BM) and xenografts in immunodeficient mice. Cotylenin A and vincristine synergistically inhibited the growth and induced apoptosis in myeloma cells. While other microtubule-disturbing agents also showed co-operative effects with cotylenin A, other anticancer agents, such as doxorubicin, cisplatin, camptothecin, methotrexate, gemcitabine and 5-fluorouracil, did not show such co-operation with cotylenin A. These differences might be attributed to the effects on autophagic responses. Combined treatment with cotylenin A and vincristine induced autophagy (formation of LC3-II and degradation of p62 protein). However, doxorubicin did not enhance the autophagy induced by cotylenin A. A colony-forming assay indicated that the combined treatment with cotylenin A and vincristine more effectively suppressed the formation of large colonies, which have higher self-renewal activity than vincristine alone. Expression of pluripotency-associated transcription factor Sox2 mRNA in RPMI-8226 myeloma cells was significantly suppressed by treatment with cotylenin A. Combined treatment with cotylenin A and vincristine significantly inhibited the growth of KMS-26 myeloma cells as xenografts. Our results suggest that the combination of cotylenin A and vincristine may have therapeutic value. Recently, it was reported that cotylenin A modulates the 14-3-3 intracellular signaling pathway. The 14-3-3 proteins may be novel targets in treating myeloma. However, our study could not explain how the sensitization to vincristine is related to the effects of cotylenin A on the 14-3-3 signaling pathway and further studies will be needed.

Spontaneous Regression of Intravascular Large B-Cell Lymphoma and Apoptosis of Lymphoma Cells: A Case Report.

A 61-year-old Japanese woman presented with hemophagocytic syndrome (HPS) and suffered from intravascular large B-cell lymphoma (IVLBCL). After a few days of supportive care, her condition improved without any anti-cancer drugs or steroids. She experienced recurrences of HPS at 15 mon and 21 mon after first presentation, but lymphoma cells were not observed. Relapse of IVLBCL with pulmonary involvement occurred 27 mon after first presentation. She underwent R-CHOP therapy followed by autologous stem cell transplantation. She is currently alive and without lymphoma. Immunostaining by anti-ssDNA suggested that spontaneous regression may have been due to apoptosis of the lymphoma cells.

Internal tandem duplication mutations in FLT3 gene augment chemotaxis to Cxcl12 protein by blocking the down-regulation of the Rho-associated kinase via the Cxcl12/Cxcr4 signaling axis.

Internal tandem duplication mutations in the Flt3 gene (ITD-FLT3) enhance cell migration toward the chemokine Cxcl12, which is highly expressed in the therapy-protective bone marrow niche, providing a potential mechanism underlying the poor prognosis of ITD-FLT3(+) acute myeloid leukemia. We aimed to investigate the mechanisms linking ITD-FLT3 to increased cell migration toward Cxcl12. Classification of the expression of Cxcl12-regulated genes in ITD-FLT3(+) cells demonstrated that the enhanced migration of ITD-FLT3(+) cells toward Cxcl12 was associated with the differential expression of genes downstream of Cxcl12/Cxcr4, which are functionally distinct from those expressed in ITD-FLT3(-) cells but are independent of the Cxcr4 expression levels. Among these differentially regulated genes, the expression of Rock1 in the ITD-FLT3(+) cells that migrated toward Cxcl12 was significantly higher than in ITD-FLT3(-) cells that migrated toward Cxcl12. In ITD-FLT3(-) cells, Rock1 expression and Mypt1 phosphorylation were transiently up-regulated but were subsequently down-regulated by Cxcl12. In contrast, the presence of ITD-FLT3 blocked the Cxcl12-induced down-regulation of Rock1 and early Mypt1 dephosphorylation. Likewise, the FLT3 ligand counteracted the Cxcl12-induced down-regulation of Rock1 in ITD-FLT3(-) cells, which coincided with enhanced cell migration toward Cxcl12. Rock1 antagonists or Rock1 shRNA abolished the enhanced migration of ITD-FLT3(+) cells toward Cxcl12. Our findings demonstrate that ITD-FLT3 increases cell migration toward Cxcl12 by antagonizing the down-regulation of Rock1 expression. These findings suggest that the aberrant modulation of Rock1 expression and activity induced by ITD-FLT3 may enhance acute myeloid leukemia cell chemotaxis to the therapy-protective bone marrow niche, where Cxcl12 is abundantly expressed.

Asian variant of intravascular large B cell lymphoma causes patients to frequently develop the syndrome of inappropriate antidiuretic hormone secretion.

The Asian variant of intravascular large B cell lymphoma is a special type of intravascular lymphoma with hemophagocytic syndrome and hypercytokinemia including interleukin-6, which stimulates antidiuretic hormone synthesis in the hypothalamus. We present here that the syndrome of inappropriate antidiuretic hormone secretion frequently occurs in patients with the Asian variant of intravascular large B cell lymphoma. The syndrome of inappropriate antidiuretic hormone secretion was found in eight of 118 (6.8%) lymphoma patients at the first diagnosis. Although there were six (5.1%) among 118 lymphoma patients with the Asian variant of intravascular large B cell lymphoma, four of the six patients (66.7%) developed the syndrome of inappropriate antidiuretic hormone secretion. In four patients with the Asian variant of intravascular large B cell lymphoma with the syndrome of inappropriate antidiuretic hormone secretion, elevated serum interleukin-6 and low sodium levels were almost normalized after chemotherapy. The Asian variant of intravascular large B cell lymphoma patients frequently develop the syndrome of inappropriate antidiuretic hormone secretion, and interleukin-6 might play a role in the occurrence of this disease. We should pay attention to hyponatremia caused by the syndrome of inappropriate antidiuretic hormone secretion in patients with the Asian variant of intravascular large B cell lymphoma.

Survivin selectively modulates genes deregulated in human leukemia stem cells.

ITD-Flt3 mutations are detected in leukemia stem cells (LSCs) in acute myeloid leukemia (AML) patients. While antagonizing Survivin normalizes ITD-Flt3-induced acute leukemia, it also impairs hematopoietic stem cell (HSC) function, indicating that identification of differences in signaling pathways downstream of Survivin between LSC and HSC are crucial to develop selective Survivin-based therapeutic strategies for AML. Using a Survivin-deletion model, we identified 1,096 genes regulated by Survivin in ITD-Flt3-transformed c-kit(+), Sca-1(+), and lineage(neg) (KSL) cells, of which 137 are deregulated in human LSC. Of the 137, 124 genes were regulated by Survivin exclusively in ITD-Flt3(+) KSL cells but not in normal CD34(neg) KSL cells. Survivin-regulated genes in LSC connect through a network associated with the epidermal growth factor receptor signaling pathway and falls into various functional categories independent of effects on apoptosis. Pathways downstream of Survivin in LSC that are distinct from HSC can be potentially targeted for selective anti-LSC therapy.

L-asparaginase-induced complete response in a relapsed patient with Epstein-Barr virus and cytotoxic peripheral T-cell lymphoma not otherwise specified.

We present a patient with Epstein-Barr virus (EBV)-positive cytotoxic peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) who was successfully treated using only L-asparaginase. A 46-year-old Japanese man was diagnosed with EBV-positive cytotoxic PTCL-NOS. Although he underwent chemotherapy using multiple agents, he relapsed with hemophagocytic syndrome. L-asparaginase treatment was initiated at 6,000 U/m(2) on days 1, 3, 5, 10, and 12 together with prednisolone at 1 mg/kg. Although he developed grade 2 liver dysfunction and grade 2 coagulopathy, the patient achieved complete response status. Finally, he underwent allogeneic bone marrow stem cell transplantation, and he is currently still alive without disease at 24 months after the start of L-asparaginase therapy.

Small bowel perforation caused by Epstein-Barr virus-associated B cell lymphoma in a patient with angioimmunoblastic T-cell lymphoma.

On rare occasions, secondary Epstein-Barr virus (EBV)-associated B cell lymphoma can develop in a patient with angioimmunoblastic T-cell lymphoma (AITL). We report a case of a 66-year-old Japanese woman who developed diffuse large B-cell lymphoma (DLBCL) in her small intestine after chemotherapy for AITL. She was found to have panperitonitis due to perforation of the small intestine. Partial ileectomy specimen showed DLBCL cells infiltrating into the intestinal wall. In situ hybridization for EBV-encoded RNA revealed positivity in the lymphoma cells. The lymph nodes diagnosed as AITL were negative for EBV infection and there was no coexistence of B cell neoplasms in them. We thought small bowel perforation in this case was caused by EBV-associated B cell lymphoma secondary to AITL. Our case showed a remarkable deficiency of cellular immunity after chemotherapy, which we postulate was related to the cause of occurrence of B-cell lymphoma.

A high risk of life-threatening infectious complications in mycophenolate mofetil treatment for acute or chronic graft-versus-host disease.

We describe herein the clinical courses and outcomes of 26 patients who received oral mycophenolate mofetil (MMF) for the treatment of steroid-resistant refractory or steroid-dependent acute or chronic graft-versus-host disease (GVHD) in a single institution. In most cases, 1,500 mg/day of MMF is a median dose (range 500-3,000 mg/day) and administered for 116.5 days (range 9-584 days) along with calcineurin inhibitors and steroids. Although 20 patients (77%) showed rapid improvement of GVHD symptoms, of 15 patients, 13 (87%) showed acute GVHD; of 11 patients, 7 (64%) showed chronic GVHD; most patients (54%) experienced infection during MMF administration, including 5 cases with life-threatening infection. Positive cytomegalovirus (CMV) antigenemia was also observed in 19 patients (73%), but no patients developed CMV infection. Within the median follow-up of 12.5 months (range 0.5-67 months), 10 patients (39%) died. This small study demonstrates that MMF offers an alternative tool for rescuing steroid-refractory or steroid-dependent GVHD, but increases the risk of developing life-threatening infection.