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Multiple myeloma is an entity of cytogenetically and genetically heterogenous plasma cell neoplasms. Despite recent improvement in the treatment outcome of multiple myeloma by novel molecular-targeted chemotherapeutics, multiple myeloma remains incurable. The identification of a therapeutic target molecule in which various signaling for cell-survival converge is a core component for the development of new therapeutic strategies against multiple myeloma. RSK2 is an essential mediator of the ERK1/2 signaling pathway for cell survival and proliferation. In this study, we discovered that RSK2Ser227, which is located at the N-terminal kinase domain and is one site responsible for substrate phosphorylation, is activated through phosphorylation regardless of the type of cytogenetic abnormalities or upstream molecular signaling in all 12 multiple myeloma–derived cell lines examined and 6 of 9 patient-derived CD138-positive primary myeloma cells. The chemical inhibition of RSK2Ser227 by BI-D1870 or gene knockdown of RSK2 inhibits myeloma cell proliferation through apoptosis induction, and this anti-myeloma effect was accompanied by downregulation of c-MYC, cyclin D, p21WAF1/CIP1, and MCL1. RSK2Ser227 inhibition resulting from BI-D1870 treatment restored lenalidomide-induced direct cytotoxicity of myeloma cells from interleukin-6–mediated cell protection, showed no cross-resistance to bortezomib, and exerted additive/synergistic antiproliferative effects in conjunction with the mTOR, histone deacetylase, and BH3-mimicking BCL2/BCLXL inhibitors. These results suggest that RSK2Ser227 is a potential therapeutic target not only for newly diagnosed but also for patients with later phase multiple myeloma who are resistant or refractory to currently available anti-myeloma therapies. Mol Cancer Ther; 11(12); 2600–9. ©2012 AACR.

PDF file - 62K, Chromosomal abnormalities and signaling molecule expression in myeloma-derived cell lines

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PDF file - 75K, Clinical information for patient-derived primary myeloma cells

Supplementary Figure S3. AMO-1 cells and NCI-H929 cells were co-cultured with HS-5 cells for 48 hours, and then were treated by BX-912 at its IC50s for 3 hours. The activities of PDPK1Ser241, RSK2Ser227 and AKTThr308 were examined by Western blotting. Ctl. indicates cells cultured without the co-culture.

Supplemental Methods and Legends

Supplementary Table S1. Clinical information of patients whose myeloma cells were subjected to Western blotting and in vitro treatment with BX-912.

Three types of chromosomal translocations, t(4;14)(p16;q32), t(14;16)(q32;q23), and t(11;14)(q13;q32), are associated with prognosis and the decision making of therapeutic strategy for multiple myeloma (MM). In this study, we developed a new diagnostic modality of the multiplex FISH in immunophenotyped cells in suspension (Immunophenotyped-Suspension-Multiplex (ISM)-FISH). For the ISM-FISH, we first subject cells in suspension to the immunostaining by anti-CD138 antibody and, then, to the hybridization with four different FISH probes for genes of IGH, FGFR3, MAF, and CCND1 tagged by different fluorescence in suspension. Then, cells are analyzed by the imaging flow cytometry MI-1000 combined with the FISH spot counting tool. By this system of the ISM-FISH, we can simultaneously examine the three chromosomal translocations, i.e, t(4;14), t(14;16), and t(11;14), in CD138-positive tumor cells in more than 2.5 × 104 nucleated cells with the sensitivity at least up to 1%, possibly up to 0.1%. The experiments on bone marrow nucleated cells (BMNCs) from 70 patients with MM or monoclonal gammopathy of undetermined significance demonstrated the promising qualitative diagnostic ability in detecting t(11;14), t(4;14), and t(14;16) of our ISM-FISH, which was more sensitive compared with standard double-color (DC) FISH examining 200 interphase cells with its best sensitivity up to 1.0%. Moreover, the ISM-FISH showed a positive concordance of 96.6% and negative concordance of 98.8% with standard DC-FISH examining 1000 interphase cells. In conclusion, the ISM-FISH is a rapid and reliable diagnostic tool for the simultaneous examination of three critically important IGH translocations, which may promote risk-adapted individualized therapy in MM.

For this study, we investigated comprehensive expression of conjoined genes (CGs) in non-Hodgkin B-cell lymphoma (B-NHL) cell line KPUM-UH1 by using paired-end RNA sequencing. Furthermore, we analyzed the expression of these transcripts in an additional 21 cell lines, 37 primary samples of various malignancies and peripheral blood mononuclear cells of four normal individuals. Seventeen CGs were detected in KPUM-UH1: CTBS-GNG5, SRP9-EPHX1, RMND5A-ANAPC, OTX1-EHBP1, ATF2-CHN1, PRKAA1-TTC33, LARP1-MRPL22, LOC105379697-BAK1, TIAM2-SCAF8, SPAG1-VPS13B, WBP1L-CNNM2, NARS2-GAB2, CTSC-RAB38, VAMP1-CD27-AS1, LRRC37A2-NSF, UBA2-WTIP and ZNF600-ZNF611. To our knowledge, 10 of these genes have not been previously reported. The various characteristics of the CGs included in- and out-of-frame fusions, chimeras involving non-coding RNA and transcript variants. A finding of note was that LARP1-MRPL2 was characterized as in-frame fusion and was recurrently expressed in B-NHL samples. In this study, variety of CGs was expressed both in malignant and normal cells, some of which might be specific to lymphoma.

RSK2 is a serine/threonine kinase downstream signaling mediator in the RAS/ERK signaling pathway and may be a therapeutic target in mantle cell lymphoma (MCL), an almost incurable disease subtype of non‐Hodgkin lymphoma. In this study, serine‐227 (RSK2Ser227) in the N‐terminal kinase domain (NTKD) of RSK2 was found to be ubiquitously active in five MCL‐derived cell lines and in tumor tissues derived from five MCL patients. BI‐D1870, an inhibitor specific to RSK2‐NTKD, caused RSK2Ser227 dephosphorylation, and thereby, induced dose‐dependent growth inhibition via G2/M cell cycle blockade and apoptosis in four of the five cell lines, while one cell line showed only modest sensitivity. In addition, RSK2 gene knockdown caused growth inhibition in the four BI‐D1870‐sensitive cell lines. Comparative gene expression profiling of the MCL‐derived cell lines showed that inhibition of RSK2Ser227 by BI‐D1870 caused downregulation of oncogenes, such as c‐MYC and MYB; anti‐apoptosis genes, such as BCL2 and BCL2L1; genes for B cell development, including IKZF1, IKZF3, and PAX5; and genes constituting the B cell receptor signaling pathway, such as CD19, CD79B, and BLNK. These findings show that targeting of RSK2Ser227 enables concomitant blockade of pathways that are critically important in B cell tumorigenesis. In addition, we found favorable combinatory growth inhibitory effects of BI‐D1870 with inhibitors of BTK (ibrutinib), AKT (ipatasertib), and BCL2 (venetoclax) in cell characteristic‐dependent manners. These results provide a rationale for RSK2Ser227 in the NTKD as a potential therapeutic target in MCL and for future development of a novel bioavailable RSK2 NTKD‐specific inhibitor., RSK2Ser227 in the N‐terminal kinase domain (NTKD) of RSK2 was found to be ubiquitously active in mantle cell lymphoma (MCL). RSK2 concomitantly regulates series of genes involved in oncogenesis, apoptosis, B cell development, and B cell receptor signaling. RSK2Ser227 in the NTKD is a potential therapeutic target in MCL.

Ruxolitinib is a selective JAK1/2 inhibitor that is widely used for the treatment of myeloproliferative neoplasms (MPNs), including myelofibrosis and polycythemia vera (PV). Despite its clinical efficacy for MPNs, ruxolitinib possesses immunosuppressive properties that potentially increase the risks for opportunistic infection, such as mycobacterium tuberculosis (MTB) infection, and reactivation of occult viral infection. Herein, we report the case of a 76-year-old male with PV who developed tuberculosis peritonitis under ruxolitinib therapy for 28 weeks. While previous studies and case reports have suggested an increased risk of MTB infection of various organs during ruxolitinib treatment of MPNs, this case is apparently the first of tuberculosis peritonitis in a patient with MPN treated with ruxolitinib. A review of previous case reports suggests the need for careful observation for MTB from the relatively early phase of ruxolitinib treatment, given that the median duration from the start of ruxolitinib treatment to the emergence of MTB was 20 weeks (range: 3-88 weeks). Clinicians should consider tuberculosis peritonitis as a differential diagnosis when patients with MPN treated with ruxolitinib develop infectious abdominal symptoms.

Background Combinatory strategies with carfilzomib (CFZ), a second‐generation proteasome inhibitor, plus dexamethasone (DEX) with or without lenalidomide (LEN) have shown promising efficacy for patients with relapsed/refractory multiple myeloma (RRMM) in pivotal clinical trials. However, their effects on patients who were resistance to bortezomib (BTZ) and/or LEN have not been fully evaluated in a daily practice setting. Aims To evaluate the real‐world efficacy and safety of CFZ‐based treatments; that is, CFZ with LEN plus DEX (KRD therapy) and CFZ with DEX (KD therapy), in Asian patients, we conducted a multicenter pilot prospective observational study in the Kyoto Clinical Hematology Study Group. Methods and Results All 50 patients with RRMM enrolled in this study were treated with CFZ‐based treatments between 2017 and 2019. KRD and KD were administered to 31 and 19 patients, respectively. The overall response rates (ORRs) were 80.6% with KRD and 73.7% with KD. Two‐year progression‐free survival (PFS) and overall survival (OS) were 58.5% and 79.7% with KRD, and 23.1% and 52.6% with KD. By multivariate analysis, refractoriness to BTZ and to LEN were identified as independent unfavorable factors for both PFS and OS. The common non‐hematologic AEs included hypertension (42.0%), fever (24.0%), fatigue (24.0%), and infection (16.0%). No serious heart failure was observed. This study is registered as UMIN000025108. Conclusion This study suggests the need of the development of novel CFZ‐containing strategy which can overcome the refractoriness to BTZ and/or LEN, while both KRD and KD were shown to be mostly feasible in Asian patients in a daily practice setting.

Primary infection with human herpesvirus-6 (HHV-6) commonly occurs at an early age in children, most often at 3 years of age, and is associated with childhood diseases, such as exanthema subitum, hepatitis, febrile convulsions, or encephalitis. However, the virus occasionally reactivates from its latent state in immunosuppressed adults, especially post-transplant, resulting in serious disseminated, sometimes life-threatening end-organ complications. Herein, we report a case of a 68-year-old man with relapsed follicular lymphoma who developed HHV-6 pneumonitis. Eighteen months after achieving second complete remission by salvage immunochemotherapy with rituximab, the patient was complicated by pneumonia, with chest computed tomography finding showing disseminated nodular shadows with ground-glass opacity in both lungs. While empiric antibiotic and antifungal therapies did not improve the pneumonia, polymerase chain reaction–based viral screening tests on his bronchoalveolar lavage fluid detected the presence of HHV-6 DNA, and ganciclovir treatment quickly resolved the pneumonia, indicating that he suffered from HHV-6 pneumonitis. He had no other HHV-6–related end-organ damage, such as encephalitis. This case suggests that, although extremely rare, HHV-6 reactivation should be considered as one of the candidate pathogens for pulmonary complications of uncertain etiology in patients who have been treated with intensive immunosuppressive chemotherapy, even without hematopoietic stem cell transplantation. Furthermore, polymerase chain reaction–based viral screening testing on bronchoalveolar lavage fluid is a powerful diagnostic tool for pneumonitis due to viral reactivation, including HHV-6 reactivation.

Introduction: Tyrosine kinase inhibitors (TKIs) dramatically improved the prognosis of chronic myelogenous leukemia (CML), as nearly half of CML patients presenting with a deep molecular response (DMR) over several years could achieve treatment-free remission. DASISION study reported dasatinib (DAS), a second-generation TKI was superior to imatinib to achieve faster and deeper response in treating newly-diagnosed chronic CML. However, standard initial dosage of 100 mg DAS/day might be too potent for patients aged >70 years with CML, possibly owing to the presence of other health conditions that threaten the life spans (e.g., lung and cardiovascular disease), thereby preventing TKI continuation. In this open-label, multicenter, single-arm, phase 2 study (DAVLEC), we evaluated the efficacy and safety of a reduced initial dose of DAS (20 mg/day) in the elderly with chronic CML. Patients and Methods: We included CML patients aged >70 years with an ECOG performance status of 0-2 and adequate organ function. After diagnosis, they began orally taking 20 mg of DAS per day. BCR-ABL mRNA values were measured and aligned to an international scale at a central laboratory to evaluate the drug's efficacy at 3, 6, 9, and 12 mo of therapy, per recommendations by European LeukemiaNet. The dosage was maintained in case of the optimal, increased by 20 mg/day when the warning appeared and could be decreased when an adverse event (AE) > grade 3 appeared. Patients were excluded if the respond was the failure or disease progression was detected. Primary endpoint was the cumulative major molecular response (MMR) rate at 12 mo. Secondary endpoints included the rates of the cumulative DMR, treatment discontinuation due to AEs, and failure to DAS treatment or disease progression. The non-inferiority of primary endpoint MMR (non-inferiority limit of 38%) was evaluated by binomial test with normal approximation. Other differences were investigated by Mann-Whitney tests, with p < 0.05 indicating significance. Results: Among the 56 patients enrolled from 25 centers, 4 declined participation, and so 52 (median age, 77.5 years) began taking 20 mg/day of DAS. In total, 73.1% of the patients had comorbidities. Median BCR-ABL values at 3, 6, and 12 mo were 1.47%, 0.23%, and 0.03%, respectively; cumulative MMR rate at 3, 6, 9, and 12 mo were 11.5%, 36.5%, 40.4%, and 59.6%, respectively. Calculated MMR at 12 mo was higher than 38%, a value selected based upon findings from the DASISION trial, accounting for a non-inferiority margin of 10% (p=0.047). At 12 mo, among the 31 patients achieving MMR, 23 were only given 20 mg DAS/day, and 14 and 7 respectively achieved MR4.0 and 4.5. Patients discontinued the study due to treatment failure (n=3), content withdrawal (n=2), drug-related AEs (Long QT Syndrome; n=1), or others (n=2). No patient discontinued it due to disease progression. Treatment-related AEs of all grades were noted in 96.2%and that of grade 3 or 4 events in 23.1% of the patients. Median dose interruptions for a median of 7 days (range: 5-36) were respectively noted in 3 and 2 patients due to hematological and non-hematological AEs. Furthermore, 4 patients experienced pleural effusion < grade 2, and 1 had lymphocytosis. Patients who achieved MMR at 12 mo (n=31) had a significantly lower BCR-ABL value at 3 mo (0.41% vs. 4.26%, p=0.0020) and a lower halving time from diagnosis to 3 mo (11.35 vs. 18.34 days, p=0.0050) than those who did not (n=21). Patients who achieved MMR by 12 mo with only 20 mg/day of DAS (n=23) had lower BCR-ABL values at 1 and 3 mo (25.51 vs. 63.63 %, p=0.00028; 0.33 vs. 5.89%, p Patients who achieved MMR at 12 mo (n=31) had higher plasma DAS concentration (23.5 vs. 8.0 ng/mL, p Conclusion: This study discovered that prescribing a starting very-low dose DAS (20 mg/day) while monitoring IS and AEs was a successful initial therapeutic strategy for the elderly with chronic CML comparable to previous studies using standard-dose. Notably, rapid BCR-ABL downregulation, early molecular responses at 1 and 3 mo, a shortened halving time from diagnosis to 3 mo, and sufficient increase in plasma DAS concentrations 2 h post-intake after 12 mo of treatment were key indicators for successful low-dose therapy. Disclosures Kumagai: Bristol-Myers Squibb: Honoraria; Novartis: Honoraria, Speakers Bureau; Pfizer: Honoraria; Otsuka Pharmaceuticals: Honoraria, Speakers Bureau. Murai: Bristol Myers Squibb: Honoraria; Otsuka Pharmaceutical Co., Ltd.: Honoraria; Novartis Pharma: Honoraria; Pfizer: Honoraria; CHUGAI Pharmaceutical Co., Ltd.: Honoraria; TAKEDA Pharmaceutical Co., Ltd.: Honoraria; DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; ONO PHARMACEUTICAL CO., LTD.: Honoraria; Asahi Kasei Pharma Corporation.: Honoraria. Tanaka: Bristol-Myers Squibb: Honoraria; Novartis: Honoraria; Pfizer: Honoraria; Otsuka Pharmaceuticals: Honoraria. Nishiwaki: Kyowa-Kirin: Research Funding; Alexion: Honoraria. Inokuchi: Bristol-Myers Squibb: Research Funding. Yoshida: Bristol-Myers Squibb: Honoraria, Research Funding; Novartis KK,: Honoraria; Pfizer Japan Inc.: Honoraria; Otsuka Pharmaceutical.: Honoraria; AbbVie GK: Honoraria; Janssen Pharmaceutical KK: Honoraria; Nippon Shinyaku: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria. Uoshima: Janssen: Honoraria; Eisai: Honoraria. Usuki: MSD K.K.: Research Funding, Speakers Bureau; Eisai Co., Ltd.: Speakers Bureau; Alexion Pharmaceuticals, Inc.: Research Funding, Speakers Bureau; Pfizer Japan Inc.: Research Funding, Speakers Bureau; Kyowa-Kirin Co., Ltd.: Research Funding, Speakers Bureau; Nippon-Shinyaku Co., Ltd.: Research Funding, Speakers Bureau; Amgen-Astellas Biopharma K.K.: Research Funding; Mundipharma K.K.: Research Funding; Nippon-Boehringer-Ingelheim Co., Ltd.: Research Funding; Takeda Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Celgene K.K.: Research Funding, Speakers Bureau; Janssen Pharmaceutical K.K.: Research Funding; Ono Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Novartis Pharma K.K.: Research Funding, Speakers Bureau; Otsuka Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Sumitomo-Dainippon Pharma Co., Ltd.: Research Funding; Daiichi Sankyo Co., Ltd.: Research Funding, Speakers Bureau; SymBio Pharmaceuticals Ltd.: Research Funding, Speakers Bureau; Gilead Sciences, Inc.: Research Funding; AbbVie GK: Research Funding, Speakers Bureau; Astellas Pharma Inc.: Research Funding, Speakers Bureau; PharmaEssentia Japan KK: Research Funding, Speakers Bureau; Yakult Honsha Co., Ltd.: Research Funding, Speakers Bureau; Bristol-Myers-Squibb K.K.: Research Funding, Speakers Bureau; Apellis Pharmaceuticals, Inc.: Research Funding; Incyte Biosciences Japan G.K.: Research Funding; Chugai Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Sanofi K.K.: Speakers Bureau; Amgen K.K.: Research Funding. Kuroda: Otsuka Pharmaceutical: Honoraria, Research Funding; Astellas Pharma: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; MSD: Research Funding; Abbvie: Consultancy, Honoraria; Ono Pharmaceutical: Honoraria, Research Funding; Eisai: Honoraria, Research Funding; Sysmex: Research Funding; Pfizer: Honoraria, Research Funding; Fujimoto Pharmaceutical: Current Employment, Honoraria, Research Funding; Taiho Pharmaceutical: Research Funding; Asahi Kasei: Research Funding; Shionogi: Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Janssen Pharmaceutical K.K: Consultancy; Bristol-MyersSquibb: Consultancy, Honoraria, Research Funding; Chugai Pharmaceutical: Honoraria, Research Funding; Dainippon Sumitomo Pharma: Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Kyowa Kirin: Honoraria, Research Funding. Ono: Chugai Pharmaceutical Co., Ltd.: Honoraria, Research Funding; Kyowa Kirin Co., Ltd.: Honoraria, Research Funding; Novartis Pharma KK: Honoraria; Otsuka Pharmaceutical Co., Ltd.: Honoraria; DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; Mundipharma K.K.: Honoraria; TAIHO PHARMACEUTICAL CO., LTD.: Research Funding; Merck Sharp & Dohme: Honoraria, Research Funding; Astellas Pharma Inc.: Honoraria; Eisai Co., Ltd.: Honoraria; Janssen Pharmaceutical K.K: Honoraria; Takeda Pharmaceutical Company Limited.: Honoraria; ONO PHARMACEUTICAL CO., LTD.: Honoraria, Research Funding; Pfizer Japan Inc.: Honoraria; Bristol-Myers Squibb Company: Honoraria; Celgene: Honoraria, Research Funding. Fujimaki: CSL Behring K.K.: Honoraria; Mundipharma K.K.: Honoraria; Takeda Pharmaceutical Company Limited: Honoraria; Meiji Seika Pharma Co., Ltd.: Honoraria; Janssen Pharmaceutical KK: Honoraria; AbbVie GK: Honoraria; Bristol-Myers Squibb: Honoraria; Novartis KK: Honoraria; Nippon Shinyaku: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria; Pfizer Japan Inc.: Honoraria; Otsuka Pharmaceutical.: Honoraria. Shibayama: Chugai: Research Funding; Eizai: Speakers Bureau; Nippon Shinyaku: Speakers Bureau; Kyowa Kirin: Speakers Bureau; AbbVie: Research Funding; Celgene: Research Funding; Novartis: Research Funding, Speakers Bureau; Ono: Research Funding, Speakers Bureau; Janssen: Research Funding, Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau; Mundi Pharma: Speakers Bureau; Otsuka: Speakers Bureau; Sanofi: Research Funding, Speakers Bureau; AstraZeneca: Research Funding, Speakers Bureau; Takeda: Speakers Bureau. Kondo: Abbvie: Honoraria; Astellas Pharma Inc.: Consultancy, Honoraria; Otsuka Pharmaceutical: Consultancy, Honoraria, Research Funding; Novartis Pharma KK: Honoraria; Bristol-Myers Squibb Company: Honoraria; Sumitomo Dainippon Pharma: Honoraria; Sanwa Kagaku Kenkyusho CO.,LTD: Consultancy; Pfizer: Honoraria. Minami: Bristol-Myers Squibb Company: Honoraria; Novartis Pharma KK: Honoraria; Pfizer Japan Inc.: Honoraria; Takeda: Honoraria; Astellas: Honoraria; Ono: Research Funding; CMIC: Research Funding. Kimura: Eisai: Speakers Bureau; Kyowa-Kirin: Research Funding, Speakers Bureau; PharmaEssentia: Speakers Bureau; Astellas: Speakers Bureau; Sanifi: Speakers Bureau; Gilead: Research Funding; Nippon-Boehringer-Ingelheim: Research Funding; Celgene: Research Funding, Speakers Bureau; Sumitomo-Dainippon: Research Funding; Chugai: Research Funding, Speakers Bureau; Mundi: Research Funding; Yakult: Research Funding, Speakers Bureau; MSD: Research Funding, Speakers Bureau; Ono: Research Funding, Speakers Bureau; SymBio: Research Funding, Speakers Bureau; Daiichi-Sankyo: Research Funding, Speakers Bureau; Janssen: Research Funding; Astellas-Amgen-Biopharma: Research Funding; Takeda: Research Funding, Speakers Bureau; Nippon-Shinyaku: Research Funding, Speakers Bureau; Amgen: Research Funding; Alexion: Research Funding, Speakers Bureau; Incyte: Research Funding; Novartis: Honoraria, Research Funding, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Research Funding, Speakers Bureau; Pfizer: Honoraria, Research Funding, Speakers Bureau; Otsuka Pharmaceutical: Honoraria, Research Funding, Speakers Bureau; Ohara Pharmaceutical: Research Funding; Astellas Pharma: Research Funding; AbbVie: Research Funding, Speakers Bureau; Apellis: Research Funding.

Cytogenetic/molecular heterogeneity is the hallmark of multiple myeloma (MM). However, we recently showed that the serine/threonine kinase PDPK1 and its substrate RPS6KA3 (also termed RSK2) are universally active in MM, and play pivotal roles in myeloma pathophysiology. In this study, we assessed involvement of aberrant miR-375 repression in PDPK1 overexpression in MM. An analysis of plasma cells from 30 pre-malignant monoclonal gammopathies of undetermined significance and 73 MM patients showed a significant decrease in miR-375 expression in patient-derived plasma cells regardless of the clinical stage, compared to normal plasma cells. Introduction of miR-375 reduced PDPK1 expression in human myeloma cell lines (HMCLs), indicating that miR-375 is the dominant regulator of PDPK1 expression. In addition, miR-375 introduction also downregulated IGF1R and JAK2 in HMCLs. CpG islands in the MIR375 promoter were pathologically hypermethylated in all 8 HMCLs examined and in most of 58 patient-derived myeloma cells. Treatment with SGI-110, a hypomethylating agent, and/or trichostatin A, a histone deacetylase inhibitor, increased miR-375 expression, but repressed PDPK1, IGF1R and JAK2 in HMCLs. Collectively, these results show the universal involvement of overlapping epigenetic dysregulation for abnormal miR-375 repression in MM, which is likely to contribute to myelomagenesis and to subsequent myeloma progression by activating oncogenic signalling pathways.

Extranodal marginal zone lymphoma (EMZL) of mucosa-associated lymphoid tissue (MALT) of the uterus is rare, and the etiology, pathophysiology and cytogenetic features remain unknown at present. The present study reports a case of a 71-year-old female with EMZL of the uterine cervix that was 80 mm in diameter and invaded directly into the rectal serosa. Complete remission was successfully induced by 6 courses of immunochemotherapy with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisolone. Although the metaphase spread of the tumor cells was unavailable for whole cytogenetic analysis, fluorescence in situ hybridization (FISH) detected triple signals for MALT1 and B-cell lymphoma 2, located at chromosome 18q21, and the centromere of chromosome 18, which was suggestive of trisomy 18, and in combination with previous studies, suggested a possible association between trisomy 18 and the large tumor at initial presentation in the present patient. In addition, FISH examination detected immunoglobulin heavy chain gene rearrangement, although the translocation partner was unconfirmed. A total of 18 previously-studied patients with EMZL of the uterus, including that of the present study, were reviewed with respect to their clinical features and treatment and cytogenetic abnormality. In the evaluation of the English scientific literature, this is the first reported patient with EMZL of the uterus with partly determined cytogenetic abnormalities.

Background Since bromodomain-containing protein 4 (BRD4) facilitates the transcription of genes important for neoplastic cells in a cancer-type specific manner, BRD4-regulated molecules may also include therapeutic targets for mantle cell lymphoma (MCL), a treatment-refractory subtype of malignant lymphoma. Materials and methods In order to uncover direct BRD4-regulated targets in MCL, we performed integrated analysis using the pathway database and the results of both gene-expression profiling and chromatin immunoprecipitation with parallel sequencing for BRD4. Results Treatment with BRD4 inhibitor I-BET151 exerted a dose-dependent inhibitory effect on cell proliferation in MCL cell lines. BRD4 was found to directly regulate series of genes involved in the B-cell receptor (BCR) signaling pathway, including B-cell linker (BLNK), paired box 5 (PAX5), and IKAROS family zinc finger 3 (IKZF3), and several oncogenes, such as MYB. Indeed, the combinatory inhibition of BCR pathway and IKZF showed an additive antitumor effect. Conclusion Concomitant targeting multiple BRD4-regulated molecules may constitute a rational therapeutic strategy for MCL.

Imatinib mesylate (IM) is a first generation ATP-competitive selective inhibitor for tyrosine kinases (TK) such as ABL, ARG, PDGFRα and b, and c-KIT.[1][1] While use of IM has markedly improved treatment outcomes of Philadelphia chromosome (Ph)-positive leukemias, including chronic myeloid leukemia

Background: Acute graft-vs-host disease (aGVHD) is a common complication of allogenic hematopoietic stem-cell transplantation (allo-HSCT) and skin is the most common and often the 1st site at which aGVHD develops. Cutaneous aGVHD is usually treated with oral and/or topical corticosteroids as the 1st-line treatment; however, steroid-refractory aGVHD not only impairs patients’ quality of life but also causes significant morbidity and mortality after allo-HSCT. Narrow-band ultraviolet B (NB-UVB) phototherapy has been utilized for a wide range of immunologic inflammatory skin diseases, but there is limited information on the efficacy, safety, and biomarkers for response prediction of NB-UVB for cutaneous aGVHD. Aims: The purpose of this study is to investigate the efficacy and safety of NB-UVB phototherapy for steroid-refractory cutaneous aGVHD. Patients and methods: A total of 40 subjects aged from 16 to 70 years with steroid-refractory cutaneous aGVHD after allo-HSCT will be included in the trial. Patients with worse than stage 2 intestine/liver aGVHD will be excluded. Eligible patients will undergo NB-UVB phototherapy until resolution or further worsening of rash or occurrence of an unmanageable adverse event. The primary endpoint is the overall response rate. The secondary outcomes include rates for complete response, partial response, stable disease, progressive disease, duration of response, sparing effect on calcineurin inhibitors and/or corticosteroids, safety, and predictive biomarkers for treatment response. Ethics and dissemination: The protocol has been approved by the institutional Clinical Research Review Board of Kyoto Prefectural University of Medicine. Written informed consent will be obtained from all patients before registration, in accordance with the Declaration of Helsinki. Results of the study will be disseminated via publications in peer-reviewed journals. Trial registration: Trial registration numbers UMIN000032426 and jRCTs052180005.

A 62-year-old man exhibiting nasal obstruction and glomerulonephritis with proteinase 3-antineutrophil cytoplasmic antibodies (PR3-ANCAs) was diagnosed with extranodal NK/T-cell lymphoma, nasal type (ENKL) with infiltration of neutrophils with apoptosis. Chemoradiotherapy reduced the tumor, improved the renal function, and decreased the PR3-ANCA levels. ANCA-positivity is observed in immunoinsufficient diseases, in which neutrophils lead to apoptosis and translocate intracellular granules, such as PR3, to the cell surface, triggering the production of ANCAs. In our case, the PR3-ANCA production was derived from the expression of PR3 on the cell surface of apoptotic neutrophils. This is the first report on ENKL describing the mechanism of ANCA development.

Several novel fusion transcripts were identified by next-generation sequencing in gastric cancer; however, the breakpoint junctions have yet to be characterized. The present study characterized a plethora of APIP-FGFR2 genomic breakpoints in the SNU-16 gastric cancer cell line, which harbored homogeneously staining regions (hsrs) and double minute chromosomes. Oligonucleotide microarrays revealed high-level amplifications at chromosomes 8q24.1 (0.8 Mb region), 10q26 (1.1 Mb) and 11p13 (1.1 Mb). These amplicons contained MYC and PVT1 at chromosome 8q24.1, BRWD2, FGFR2 and ATE1 at chromosome 10q26, and 24 genes, including APIP, CD44, RAG1 and RAG2, at chromosome 11p13. Based on these findings, reverse transcription-polymerase chain reaction (PCR) was performed using various candidate gene primers to detect possible fusion transcripts, and several products using primer sets for the APIP and FGFR2 genes were detected. Eventually, three in-frame and two out-of-frame fusion transcripts were detected. Notably, PCR analysis of the entire genomic DNA detected three distinct genomic junctions. The breakpoints were within intron 5 of APIP, which contained three distinct breakpoints, and introns 5, 7 and 9 of FGFR2. Fluorescence in situ hybridization showed several fusion signals within hsrs using two short probes (~10-kb segments of a bacterial artificial chromosome clone) containing exons 2-5 of APIP or exons 11-13 of FGFR2. Although, for any given fusion, a multiplicity of transcripts is thought to be created by alternative splicing of one rearranged allele, the results of the present study suggested that genomic fusions of APIP and FGFR2 are generated in hsrs with a diversity of breakpoints that are then faithfully transcribed.

Chromosome instability (CIN), the hallmarks of cancer, reflects ongoing chromosomal changes caused by chromosome segregation errors and results in whole chromosomal or segmental aneuploidy. In multiple myeloma (MM), CIN contributes to the acquisition of tumor heterogeneity, and thereby, to disease progression, drug resistance, and eventual treatment failure, however, the underlying mechanism of CIN in MM remains unclear. Faithful chromosomal segregation is tightly regulated by a series of mitotic checkpoint proteins, such as budding uninhibited by benzimidazoles 1 (BUB1). In this study, we found that BUB1 was overexpressed in patient-derived myeloma cells, and BUB1 expression was significantly higher in patients in an advanced stage compared to those in an early stage. This suggested the involvement of aberrant BUB1 overexpression in disease progression. In human myeloma-derived cell lines (HMCLs), BUB1 knockdown reduced the frequency of chromosome segregation errors in mitotic cells. In line with this, partial knockdown of BUB1 showed reduced variations in chromosome number compared to parent cells in HMCLs. Finally, BUB1 overexpression was found to promote the clonogenic potency of HMCLs. Collectively, these results suggested that enhanced BUB1 expression caused an increase in mitotic segregation errors and the resultant emergence of subclones with altered chromosome numbers and, thus, was involved in CIN in MM.

The combinations of melphalan, bortezomib, and prednisolone (VMP) and of lenalidomide and dexamethasone (Rd) are standard treatment strategies for transplant-ineligible newly diagnosed multiple myeloma (NDMM). To make the most of these two strategies, we investigated the efficacy and feasibility of first-line treatment with 4 cycles of VMP followed by continuous Rd therapy in a multi-institutional phase 2 study in Japanese patients with transplant-ineligible NDMM. Thirty-six patients of median age 74 years old with NDMM initially received 35-day cycles of VMP: oral melphalan (6 mg/m2) and prednisolone (60 mg/m2) on days 1 to 4 and bortezomib (1.3 mg/m2) on days 1, 8, 15, and 22. After 4 cycles of VMP, treatment was switched to 28-day cycles of Rd, which was continued until disease progression or emergence of an unacceptable adverse event (AE) in 33 patients, while one patient who achieved CR after VMP continued VMP at the physician's discretion. The overall response rates after VMP and after Rd were 66.7% and 86.1%, including CR rates of 5.6% and 36.1%, respectively. In a median follow-up period of 34.3 months, the progression-free survival and overall survival rates at 3 years were 43.2% and 81.3%, respectively. Grade 3-4 hematological AEs included neutropenia (39% with VMP and 24% with Rd) and thrombocytopenia (11% with VMP and 3% with Rd). There was no death due to an AE. In conclusion, sequential therapy with VMP followed by Rd is effective and mostly feasible for transplant-ineligible NDMM. The study is registered as UMIN000034815.

Cyclin D1 (CCND1) overexpression is an early and unifying oncogenic event in mantle cell lymphoma (MCL) and multiple myeloma (MM) with chromosome 11q13 abnormalities. Herein, we report newly discovered transcript variants of the CCND1 gene in MCL and MM cells with chromosome 11q13 abnormalities. These transcript variants, designated CCND1.tv., covered the full-length coding region of CCND1 with longer 5'-untranslated regions (5'-UTRs) of CCND1 and occasionally contained a novel exon. CCND1.tv. was specifically detectable in patient-derived primary MCL or MM cells with chromosomal translocation t(11;14)(q13;q32), but not in t(11;14)-negative cells. The lengths of the 5'-UTR sequences of CCND1.tv. differed among patients and cell lines. Introduction of CCND1.tv. led to increased expression of normal-sized CCND1 protein in HEK293 cells. Furthermore, mTOR inhibition by rapamycin or serum starvation reduced ectopic expression of CCND1.tv.-derived CCND1 protein, but not 5'-UTR less CCND1-derived CCND1 protein in HEK293 cells, suggesting that the protein expression of CCND1.tv. is regulated by the mTOR pathway. Our results suggest that the aberrant expression of CCND1.tv. may contribute to the understanding of the pathogenesis of MCL and MM with 11q13 abnormalities.

An individual with a twin who has developed leukemia or non-Hodgkin lymphoma (NHL) has an increased risk of developing the same disease, particularly with monozygotic twins. The few reported pairs of twins who developed NHL had similar primary sites and pathological subtypes. Here, we present the first reported cases of primary conjunctival NHL in both female monozygotic twins. Twin 1 was diagnosed with an extranodal marginal zone lymphoma (EMZL; Ann Arbor stage IE) in the right conjunctiva at 25 years old and a subsequent tumor in the left conjunctiva at 39 years, and was also histopathologically diagnosed as EMZL. No infiltration of other organs was detected and both lesions were surgically excised. At the age of 40 years, Twin 2 was diagnosed with an EMZL (Ann Arbor stage IE) in the right conjunctiva without infiltration of other organs and was treated with external beam radiation therapy rather than surgery. Complete remission was achieved in both twins; neither developed conjunctival recurrences. This study highlights the importance of examining the other, apparently healthy twin when one twin develops conjunctival lymphoma.

Background/Aim: Bendamustine hydrochloride (BH) is a key therapeutic agent for mantle cell lymphoma (MCL), while the mechanism underlying BH-resistance has not been verified. Materials and Methods: We compared molecular/biological characteristics of a newly-generated MCL-derived cell line KPUM-YY1 and its BH-resistant subline KPUM-YY1R. Results: The growth-inhibitory IC50 for BH was 20 μM in KPUM-YY1 cells, while cell proliferation was not inhibited by up to 60 μM BH in KPUM-YY1R cells. Compared to KPUM-YY1 cells, gene expression profiling in KPUM-YY1R cells revealed up-regulation of 312 genes, including ABCB1 encoding P-glycoprotein (P-gp), and microsomal glutathione S-transferase 1 (MGST1). Addition of either a P-gp inhibitor or a GST inhibitor, at least partly, restored sensitivity to BH in KPUM-YY1R cells. In addition, KPUM-YY1R cells showed cross-resistance against various anti-MCL chemotherapeutics. Conclusion: BH resistance is mediated by overlapping mechanisms with overexpression of ABCB1 and MGST1, and is potentially accompanied by multidrug resistance in MCL.

We herein report a rare case of Burkitt lymphoma (BL) preceded by autoimmune hemolytic anemia (AIHA) caused by autoantibodies against D antigen. After a partial response to AIHA with prednisolone (PSL) treatment for 7 months, the patient developed BL with a t(8;22)(q24;q11.2) chromosomal translocation. Intensive immunochemotherapy, including rituximab, led to a complete response (CR) of BL; however, anti-D antibody remained detectable in the plasma and antibody-dissociated solution from erythrocytes, thus continuous therapy with PSL was necessary even after achievement of the CR. BL with AIHA is extremely rare, with only one previously reported case in the literature.

We investigated clinical and genetic characteristics of high-risk follicular lymphoma (FL), that lacked evidence of large cell transformation at diagnosis, in the rituximab era. First, we retrospectively analysed the clinical features of 100 patients with non-transformed FL that were consecutively treated with rituximab-containing therapies in a discovery cohort. The presence of either peripheral blood and/or bone involvement was associated with short progression-free survival. This was confirmed in a validation cohort of 66 FL patients. Then, whole exome sequencing was performed on randomly selected 5 high- and 9 standard-risk FL tumours. The most common mutational signature was a CG > TG substitution-enriched signature associated with spontaneous deamination of 5-methylcytosine at CpG, but mutations in WA and WRC(Y) motifs (so-called activation-induced cytidine deaminase (AID) motifs) were also enriched throughout the whole exome. We found clustered mutations in target sequences of AID in the IG and BCL2 loci. Importantly, high-risk FLs harboured more somatic mutations (mean 190 vs. 138, P = 0.04), including mutations in WA (33 vs. 22, P = 0.038), WRC (34 vs. 22, P = 0.016) and WRCY motifs (17 vs. 11, P = 0.004). These results suggest that genomic instability that allows for emergence of distinct mutations through AID activity underlies development of the high-risk FL phenotype.

Mantle cell lymphoma (MCL) is a relatively rare subtype of B-cell non-Hodgkin lymphoma (NHL) that has a poor prognosis despite recent advances in immunochemotherapy and molecular targeted therapeutics against NHL. Therefore, the development of a new therapeutic strategy for MCL is urgently needed. In this study, we show for the first time that 3-phosphoinositide-dependent protein kinase 1 (PDPK1), an oncogenic serine–threonine protein kinase, is commonly expressed in its phosphorylated active form in patient-derived tumor cells of various types of B-cell NHL cells, including diffuse large B-cell lymphoma, follicular lymphoma, and MCL. Blockade of PDPK1 activity by small-molecule inhibitors specific for PDPK1 (BX-912 and GSK2334470) or by RNA interference exerted antiproliferative effects in all four MCL-derived cell lines examined and these growth-inhibitory effects were mediated by both induction of apoptosis and G 2 /M cell cycle blockade. In addition, blockade of PDPK1 led to inactivation of its downstream effector kinase RSK2, but not AKT, suggesting the importance of the PDPK1/RSK2 signaling pathway in the proliferation and survival of MCL cells. Finally, when combined with anticancer agents, including genotoxic agents, a proteasome inhibitor, and a BH3 mimetic in vitro, the PDPK1 inhibitor BX-912 showed additive growth-inhibitory effects against MCL-derived cell lines in most settings. In particular, the combination of BX-912 and ABT-263, a BH3 mimetic, resulted in the enhancement of the induction of apoptosis. In conclusion, our results suggest that PDPK1 is a potential novel therapeutic target in MCL and indicate that clinical development of PDPK1-targeted therapy for MCL is desirable.

Azacitidine is the first-line therapeutic option for myelodysplastic syndrome (MDS). This report describes a case of MDS in a patient who developed fatal acute interstitial pneumonitis (AIP) after the first seven-day course of intravenous azacitidine (75 mg/m(2)/day) treatment. A review of previous and present studies of azacitidine-associated AIP suggests that azacitidine may cause life-threatening AIP during or after the first seven-day course of treatment, with pyrexia commonly preceding AIP. Although the non-hematologic adverse events associated with azacitidine are generally relatively mild, further accumulation of evidence may help to make an earlier diagnosis of azacitidine-associated AIP.

We report the case of a 72-year-old man who presented with non-producing multiple myeloma (MM) with three additional concomitant solid tumors that were identified by postmortem autopsy. The disease was refractory to anti-MM therapy including bortezomib and lenalidomide, and he finally died of bacterial pneumonia with diffuse alveolar damage 8 months after the diagnosis. An autopsy revealed that he was also affected by three other solid cancers, cholangiocellular carcinoma, medullary thyroid cancer and papillary thyroid cancer that were clinically asymptomatic and remained undiagnosed before death. A review of the literature suggests that primary quadruple cancers including MM are extremely rare.

Multiple myeloma is an entity of cytogenetically and genetically heterogenous plasma cell neoplasms. Despite recent improvement in the treatment outcome of multiple myeloma by novel molecular-targeted chemotherapeutics, multiple myeloma remains incurable. The identification of a therapeutic target molecule in which various signaling for cell-survival converge is a core component for the development of new therapeutic strategies against multiple myeloma. RSK2 is an essential mediator of the ERK1/2 signaling pathway for cell survival and proliferation. In this study, we discovered that RSK2Ser227, which is located at the N-terminal kinase domain and is one site responsible for substrate phosphorylation, is activated through phosphorylation regardless of the type of cytogenetic abnormalities or upstream molecular signaling in all 12 multiple myeloma–derived cell lines examined and 6 of 9 patient-derived CD138-positive primary myeloma cells. The chemical inhibition of RSK2Ser227 by BI-D1870 or gene knockdown of RSK2 inhibits myeloma cell proliferation through apoptosis induction, and this anti-myeloma effect was accompanied by downregulation of c-MYC, cyclin D, p21WAF1/CIP1, and MCL1. RSK2Ser227 inhibition resulting from BI-D1870 treatment restored lenalidomide-induced direct cytotoxicity of myeloma cells from interleukin-6–mediated cell protection, showed no cross-resistance to bortezomib, and exerted additive/synergistic antiproliferative effects in conjunction with the mTOR, histone deacetylase, and BH3-mimicking BCL2/BCLXL inhibitors. These results suggest that RSK2Ser227 is a potential therapeutic target not only for newly diagnosed but also for patients with later phase multiple myeloma who are resistant or refractory to currently available anti-myeloma therapies. Mol Cancer Ther; 11(12); 2600–9. ©2012 AACR.

Transient thrombocytopenia is common after autologous peripheral blood stem cell transplantation (auto-PBSCT). Although patients underwent auto-PBSCT usually show the recovery of peripheral leukocytes and platelets counts within a couple of weeks after auto-PBSCT, delayed platelet engraftment (DPE) is occasionally observed despite prompt neutrophil engraftment. However, there are few studies evaluating the risk factors for DPE. In this study, to investigate the association between clinical characteristics and duration required for post-auto-PBSCT platelet engraftment, we retrospectively analyzed 144 patients with B-cell non-Hodgkin lymphomas who underwent auto-PBSCT between January 2000 and December 2017 at 5 independent institutes involved in the Kyoto Clinical Hematology Study Group. Platelet recovery was defined as a recovery of platelet count greater than 50.0 × 109/L without transfusion support for 3 consecutive days, and the first day of 3 consecutive days was regarded as the day of platelet engraftment. The median observation period was 930 days (range, 25 - 5272 days). Median age at auto-PBSCT was 61, and 144 patients included 109 diffuse large B cell lymphoma, 11 follicular lymphoma, 22 mantle cell lymphoma. Ninety one patients were in complete remission at the time of auto-PBSCT. The mobilization regimens for stem cell collection were chemotherapy such as high-dose VP16 (46.5%), CHASE (cyclophosphamide, AraC, VP16, and dexamethasone) (40.3%), and high-dose AraC (8.3%) followed by G-CSF. All 144 patients except one achieved neutrophil engraftment with the median engraftment day of 10 days (range, 4-41 days), and 139 patients achieved platelet engraftment with the median engraftment day of 19 days (range, 10-1125 days). Multivariate analysis showed that infused CD34-positive cell number (≥ 2.0 × 106/kg vs. < 2.0 ×106/kg: HR 3.06: P < 0.001), pre-apheresis absolute lymphocyte count (PA-ALC), which was the mean number of lymphocytes during aphaeresis procedure (≥ 1.0 × 109/L vs. < 1.0 × 109/L: HR 2.62: P < 0.001), and the days required for apheresis procedure (≥ 3 days vs. 1 or 2 days: HR 0.49: P = 0.02) were independently associated with the duration for platelet engraftment after auto-PBSCT. Age, gender, diagnosis, Ann Arbor stages, previous history of bone marrow infiltration, performance status, international prognostic index (IPI)-defined disease risk, disease status at the time of transplant, the number of chemotherapy regimens, and mobilization regimen were not associated with platelet engraftment period. On the basis of these results, we next tried to create a new prediction system for post-transplant platelet recovery by incorporating the three factors, i.e., infused CD34-positive cell number, PA-ALC, and days required for apheresis procedure. Risk groups were determined by the sum of predictive factors for platelet recovery: favorable (3 factors), intermediate (2 factors), unfavorable (1 factor), and very unfavorable (no factor). As the results, the median duration for platelet engraftment with favorable, intermediate, unfavorable, and very unfavorable groups were 15, 19, 31, and 148 days, respectively (P < 0.001) (Figure). Furthermore, 14 of 144 patients did not achieve platelet engraftment by day 80 after auto-PBSCT. We defined those as patients with DPE. Median duration for platelet engraftment in patients with DPE was 137 days (range, 82-1125 days), while that for neutrophil engraftment was 11 days. Intriguingly, PA-ALC was less than 1.0 × 109/L in all 14 patients with DPE, while 6 required apheresis for ≥3 days, and 5 received Figure Figure. Disclosures Kuroda: Chugai Pharma: Honoraria, Research Funding.

The AML1 gene is frequently rearranged by chromosomal translocations in acute leukemia. We identified that the LAF4 gene on 2q11.2-12 was fused to the AML1 gene on 21q22 in a pediatric patient having T-cell acute lymphoblastic leukemia (T-ALL) with t(2;21)(q11;q22) using the bubble PCR method for cDNA. The genomic break points were within intron 7 of AML1 and of LAF4, resulting in the in-frame fusion of exon 7 of AML1 and exon 8 of LAF4. The LAF4 gene is a member of the AF4/FMR2 family and was previously identified as a fusion partner of MLL in B-precursor ALL with t(2;11)(q11;q23), although AML1-LAF4 was in T-ALL. LAF4 is the first gene fused with both AML1 and MLL in acute leukemia. Almost all AML1 translocations except for TEL-AML1 are associated with myeloid leukemia; however, AML1-LAF4 was associated with T-ALL as well as AML1-FGA7 in t(4;21)(q28;q22). These findings provide new insight into the common mechanism of AML1 and MLL fusion proteins in the pathogenesis of ALL. Furthermore, we successfully applied bubble PCR to clone the novel AML1-LAF4 fusion transcript. Bubble PCR is a powerful tool for detecting unknown fusion transcripts as well as genomic fusion points.

Multiple myeloma is a cytogenetically/molecularly heterogeneous hematologic malignancy that remains mostly incurable, and the identification of a universal and relevant therapeutic target molecule is essential for the further development of therapeutic strategy. Herein, we identified that 3-phosphoinositide–dependent protein kinase 1 (PDPK1), a serine threonine kinase, is expressed and active in all eleven multiple myeloma–derived cell lines examined regardless of the type of cytogenetic abnormality, the mutation state of RAS and FGFR3 genes, or the activation state of ERK and AKT. Our results revealed that PDPK1 is a pivotal regulator of molecules that are essential for myelomagenesis, such as RSK2, AKT, c-MYC, IRF4, or cyclin Ds, and that PDPK1 inhibition caused the growth inhibition and the induction of apoptosis with the activation of BIM and BAD, and augmented the in vitro cytotoxic effects of antimyeloma agents in myeloma cells. In the clinical setting, PDPK1 was active in myeloma cells of approximately 90% of symptomatic patients at diagnosis, and the smaller population of patients with multiple myeloma exhibiting myeloma cells without active PDPK1 showed a significantly less frequent proportion of the disease stage III by the International Staging System and a significantly more favorable prognosis, including the longer overall survival period and the longer progression-free survival period by bortezomib treatment, than patients with active PDPK1, suggesting that PDPK1 activation accelerates the disease progression and the resistance to treatment in multiple myeloma. Our study demonstrates that PDPK1 is a potent and a universally targetable signaling mediator in multiple myeloma regardless of the types of cytogenetic/molecular profiles. Cancer Res; 74(24); 7418–29. ©2014 AACR.

This report concerns a 62-year-old man with primary cutaneous diffuse large B-cell lymphoma (PCLBCL), leg type that developed during methotrexate (MTX) treatment for rheumatoid arthritis (RA). Several tumors were observed on the left lower leg. A histological analysis showed diffuse proliferation of large neoplastic B-cells that were immunophenotypically CD10-/MUM1+/BCL6-/BCL2+ and cytogenetically had IgH/c-MYC translocation without translocation involving BCL6 or IgH/BCL2. No evidence of Epstein-Barr virus (EBV) infection was found. The discontinuation of MTX resulted in a 20-month disease-free period. No previous cases of PCLBCL, leg type associated with RA or MTX therapy have been reported. The phenotypes of our patient were partly different from those of typical PCLBCL, leg type or RA/MTX-associated lymphoma.