Acute accumulation of PIM2 and NRF2 and recovery of β5 subunit activity mitigate multiple myeloma cell susceptibility to proteasome inhibitors.

Resistance to proteasome inhibitors (PIs) has emerged as an important clinical issue. We investigated the mechanisms underlying multiple myeloma (MM) cell resistance to PIs. To mimic their pharmacokinetic/pharmacodynamic (PK/PD) profiles, MM cells were treated with bortezomib and carfilzomib for 1 h at concentrations up to 400 and 1,000 nM, respectively. Susceptibility to these PIs markedly varied among MM cell lines. Pulsatile treatments with PIs suppressed translation, as demonstrated by incorporation of puromycin at 24 h in PI-susceptible MM.1S cells, but not PI-resistant KMS-11 cells. Inhibition of β5 subunit activity decreased at 24 h in KMS-11 cells, even with the irreversible PI carfilzomib, but not under suppression of protein synthesis with cycloheximide. Furthermore, the proteasome-degradable pro-survival factors PIM2 and NRF2 acutely accumulated in MM cells subjected to pulsatile PI treatments. Accumulated NRF2 was trans-localized into the nucleus to induce the expression of its target gene, HMOX1, in MM cells. PIM and Akt inhibition restored the anti-MM effects of PIs, even against PI-resistant KMS-11 cells. Collectively, these results suggest that increased synthesis of β5 proteasome subunit and acute accumulation of PIM2 and NRF2 reduce the anti-MM effects of PIs.


Novel antimyeloma therapeutic option with inhibition of the HDAC1-IRF4 axis and PIM kinase

Multiple myeloma (MM) preferentially expands and acquires drug resistance in the bone marrow (BM). We herein examined the role of histone deacetylase 1 (HDAC1) in the constitutive activation of the master transcription factor IRF4 and the prosurvival mediator PIM2 kinase in MM cells. The knockdown or inhibition of HDAC1 by the class I HDAC inhibitor MS-275 reduced the basal expression of IRF4 and PIM2 in MM cells. Mechanistically, the inhibition of HDAC1 decreased IRF4 transcription through histone hyperacetylation and inhibiting the recruitment of RNA polymerase II at the IRF4 locus, thereby reducing IRF4-targeting genes, including PIM2. In addition to the transcriptional regulation of PIM2 by the HDAC1-IRF4 axis, PIM2 was markedly upregulated by external stimuli from BM stromal cells and interleukin-6 (IL-6). Upregulated PIM2 contributed to the attenuation of the cytotoxic effects of MS-275. Class I HDAC and PIM kinase inhibitors cooperatively suppressed MM cell growth in the presence of IL-6 and in vivo. Therefore, the present results demonstrate the potential of the simultaneous targeting of the intrinsic HDAC1-IRF4 axis plus externally activated PIM2 as an efficient therapeutic option for MM fostered in the BM.


Motivation for physical activity before and after allogeneic hematopoietic stem cell transplantation.

This study aimed to identify patient motivation for physical activity before and after allogeneic hematopoietic stem cell transplantation (HSCT). We conducted 14 semi-structured interviews of seven patients (two of each patient): one before starting a conditioning regimen and one after leaving the protected environment. All interviews were recorded and analyzed using the inductive content analysis method. The data collection period was May to December 2018. The participants comprised three men and four women aged 40-70 years. The patients underwent bone marrow, umbilical cord blood, or peripheral HSCT. The patients' motivation for physical activity before and after HSCT was classified into six categories and categorized into five themes including "to overcome HSCT," "to look after myself," "to respond to the donor," "the existence of supporters," and "encouragement from supporters." The categories and themes developed here based on patient responses provide an important perspective that should be promoted among healthcare providers who care for patients undergoing HSCT.


徳島県におけるHIV感染症および後天性免疫不全症候群患者の臨床的特徴と今後の課題

【Introduction】The survival rate in patients with HIV infection and acquired immunodeficiency syndrome (AIDS) has been improved dramatically due to the advances in anti-HIV drug therapy, while aging-associated complications become a critical issue. The incidence of sudden occurrence of AIDS without prior detection of HIV infection, so called ``Ikinari AIDS'', still remains high. 【Objective】We retrospectively analyzed the incidence and clinical characteristics of HIV/AIDS patients in both Tokushima University Hospital and Tokushima Prefectural Central Hospital. 【Results】Eighty four patients (74 males and 10 females) with a median age of 39 years old (range 16 - 85) were enrolled. Thirty-four patients (40.5%) were diagnosed with ``Ikinari AIDS'' from 2001 to 2020. All 4 patients were diagnosed with ``Ikinari AIDS'' after 2020. AIDS-defining illnesses were diagnosed as follows ; pneumocystis pneumonia in 21 cases, CMV infection in 8 cases and candidiasis in 6 cases. All patients over 60 years old were suffered from AIDS. Other complications included syphilis in 17 cases, hepatitis B infection in 12 and herpes zoster in 7. 【Discussion/Conclusion】In Tokushima, the incidence rate of ``Ikinari AIDS'' appeared to be higher than that of national average. COVID - 19 pandemic hampered the public health care services of awareness-raising activity for HIV infection and telephone consultations about HIV, which may become more lease asymptomatic HIV patients without diagnosis. For early diagnosis of HIV/AIDS, it is becoming more important to share information to make early screening of HIV infection among medical staffs, such as medical doctors, dentists, nurses, pharmacists and MSWs.


First reported case of Lachnoanaerobaculum gingivalis bacteremia in an acute myeloid leukemia patient with oral mucositis during high dose chemotherapy.

During chemotherapy in patients with oral mucositis, we should consider the possibility of L. gingivalis bacteremia.


A machine learning model using SNPs obtained from a genome-wide association study predicts the onset of vincristine-induced peripheral neuropathy

Vincristine treatment may cause peripheral neuropathy. In this study, we identified the genes associated with the development of peripheral neuropathy due to vincristine therapy using a genome-wide association study (GWAS) and constructed a predictive model for the development of peripheral neuropathy using genetic information-based machine learning. The study included 72 patients admitted to the Department of Hematology, Tokushima University Hospital, who received vincristine. Of these, 56 were genotyped using the Illumina Asian Screening Array-24 Kit, and a GWAS for the onset of peripheral neuropathy caused by vincristine was conducted. Using Sanger sequencing for 16 validation samples, the top three single nucleotide polymorphisms (SNPs) associated with the onset of peripheral neuropathy were determined. Machine learning was performed using the statistical software R package "caret". The 56 GWAS and 16 validation samples were used as the training and test sets, respectively. Predictive models were constructed using random forest, support vector machine, naive Bayes, and neural network algorithms. According to the GWAS, rs2110179, rs7126100, and rs2076549 were associated with the development of peripheral neuropathy on vincristine administration. Machine learning was performed using these three SNPs to construct a prediction model. A high accuracy of 93.8% was obtained with the support vector machine and neural network using rs2110179 and rs2076549. Thus, peripheral neuropathy development due to vincristine therapy can be effectively predicted by a machine learning prediction model using SNPs associated with it.


Allogeneic haematopoietic stem cell transplantation and patient falls: impact of lower extremity muscle strength.

Pretransplant LEMS was a significant predictor of post-transplant falls. The results of this study may help to prevent falls in patients undergoing allo-HSCT.


A genome-wide association study predicts the onset of dysgeusia due to anti-cancer drug treatment

Dysgeusia is a major side effect of anti-cancer drug treatment. Since dysgeusia significantly lowers the patient's QOL, predicting and avoiding its onset in advance is desirable. Accordingly, aims of the present study were to use a genome-wide association study (GWAS) to identify genes associated with the development of dysgeusia in patients taking anti-cancer drugs and to predict the development of dysgeusia using associated single nucleotide polymorphisms (SNPs). GWAS was conducted on 76 patients admitted to the Department of Hematology, Tokushima University Hospital. Using Sanger sequencing for 23 separately collected validation samples, the top two SNPs associated with the development of dysgeusia were determined. GWAS identified rs73049478 and rs41396146 SNPs on the retinoic acid receptor beta (RARB) gene associated with dysgeusia development due to the administration of anti-cancer drugs. Evaluation of the two SNPs using 23 validation samples indicated that the accuracy rate of rs73049478 was relatively high (87.0%). Thus, the findings of the present study suggest that the rs73049478 SNP of RARB can be used to predict the onset of dysgeusia caused by the administration of anti-cancer drugs.


Allogeneic haematopoietic stem cell transplantation-clinical outcomes: impact of leg muscle strength.

Pre-transplant LEMS was a significant factor in predicting OS and NRM.


TAK1 is a pivotal therapeutic target for tumor progression and bone destruction in myeloma

Along with the tumor progression, the bone marrow microenvironment is skewed in multiple myeloma (MM), which underlies the unique pathophysiology of MM and confers aggressiveness and drug resistance in MM cells. TGF-β-activated kinase-1 (TAK1) mediates a wide range of intracellular signaling pathways. We demonstrate here that TAK1 is constitutively overexpressed and phosphorylated in MM cells, and that TAK1 inhibition suppresses the activation of NF-κB, p38MAPK, ERK and STAT3 to decrease the expression of critical mediators for MM growth and survival, including PIM2, MYC, Mcl-1, IRF4, and Sp1, along with a substantial reduction in the angiogenic factor VEGF in MM cells. Intriguingly, TAK1 phosphorylation was also induced along with upregulation of vascular cell adhesion molecule-1 (VCAM-1) in bone marrow stromal cells (BMSCs) in cocultures with MM cells, which facilitated MM cell-BMSC adhesion while inducing IL-6 production and receptor activator of nuclear factor κ-Β ligand (RANKL) expression by BMSCs. TAK1 inhibition effectively impaired MM cell adhesion to BMSCs to disrupt the support of MM cell growth and survival by BMSCs. Furthermore, TAK1 inhibition suppressed osteoclastogenesis enhanced by RANKL in cocultures of bone marrow cells with MM cells, and restored osteoblastic differentiation suppressed by MM cells or inhibitory factors for osteoblastogenesis overproduced in MM. Finally, treatment with the TAK1 inhibitor LLZ1640-2 markedly suppressed MM tumor growth and prevented bone destruction and loss in mouse MM models. Therefore, TAK1 inhibition may be a promising therapeutic option targeting not only MM cells but also the skewed bone marrow microenvironment in MM.


Acute Myeloid Leukemia Developing with Acute Pancreatitis Mimicking Autoimmune Pancreatitis.

A 33-year-old man was admitted to our hospital for fever and abdominal pain. A blood analysis revealed pancytopenia and increased serum pancreatic enzymes with disseminated intravascular coagulation. A detailed examination revealed acute pancreatitis, with diffuse swelling of the pancreas and diffuse beaded dilatation of the main pancreatic duct, which mimicked autoimmune pancreatitis complicated by acute myeloid leukemia. Systemic cytotoxic chemotherapy led to the remission of leukemia and pancreatitis. We hypothesized that the etiology of acute pancreatitis was invasion of leukemia cells. Acute pancreatitis is rare as a symptom of leukemia; however, we should consider the possibility of leukemia during the differential diagnosis of acute pancreatitis.


Association analysis between adverse drug reactions to cytarabine therapy and single nucleotide polymorphisms in cytarabine metabolic genes in patients with hematopoietic tumor


Intravenous busulfan-based conditioning with autologous stem cell transplantation for refractory B-cell lymphoma with central nervous system involvement.

The prognosis of relapsed or refractory lymphoma with central nervous system (CNS) involvement remains poor because of the lack of anticancer drugs with sufficient CNS penetration. [Case 1] A 65-year-old man was diagnosed with Stage IV mantle cell lymphoma. After two courses of chemotherapy and autologous hematopoietic stem cell (HSC) collection, urinary retention with fever developed. Cerebrospinal fluid analysis revealed leptomeningeal involvement, which was refractory to high-dose methotrexate therapy. Autologous peripheral blood stem cell transplantation (ASCT) was performed, followed by intravenous busulfan (ivBU), cyclophosphamide, and etoposide ; thereafter, no relapse has been detected for over six years. [Case 2] A 40-year-old woman with right lower hemiplegia was diagnosed with primary CNS lymphoma. Although four courses of high-dose methotrexate therapy were administered, the cerebral tumor increased in size. HSCs were collected after methotrexate therapy, and ASCT was performed in addition to conditioning using ivBU, cyclophosphamide, and etoposide, followed by whole-brain and local boost irradiation. She achieved complete remission, but relapsed two years after ASCT. High-dose ivBU-containing conditioning regimens with ASCT may be useful for refractory B-cell lymphoma with CNS involvement. J. Med. Invest. 68 : 196-201, February, 2021.

The Journal of Medical Investigation : JMI


The Roles of ROS Generation in RANKL-Induced Osteoclastogenesis: Suppressive Effects of Febuxostat.

Receptor activator of NF-κB ligand (RANKL), a critical mediator of osteoclastogenesis, is upregulated in multiple myeloma (MM). The xanthine oxidase inhibitor febuxostat, clinically used for prevention of tumor lysis syndrome, has been demonstrated to effectively inhibit not only the generation of uric acid but also the formation of reactive oxygen species (ROS). ROS has been demonstrated to mediate RANKL-mediated osteoclastogenesis. In the present study, we therefore explored the role of cancer-treatment-induced ROS in RANKL-mediated osteoclastogenesis and the suppressive effects of febuxostat on ROS generation and osteoclastogenesis. RANKL dose-dependently induced ROS production in RAW264.7 preosteoclastic cells; however, febuxostat inhibited the RANKL-induced ROS production and osteoclast (OC) formation. Interestingly, doxorubicin (Dox) further enhanced RANKL-induced osteoclastogenesis through upregulation of ROS production, which was mostly abolished by addition of febuxostat. Febuxostat also inhibited osteoclastogenesis enhanced in cocultures of bone marrow cells with MM cells. Importantly, febuxostat rather suppressed MM cell viability and did not compromise Dox's anti-MM activity. In addition, febuxostat was able to alleviate pathological osteoclastic activity and bone loss in ovariectomized mice. Collectively, these results suggest that excessive ROS production by aberrant RANKL overexpression and/or anticancer treatment disadvantageously impacts bone, and that febuxostat can prevent the ROS-mediated osteoclastic bone damage.


Successful treatment of progressive multifocal leukoencephalopathy with mirtazapine and mefloquine in refractory myeloma


Polyclonal Immunoglobulin Recovery after Autologous Stem Cell Transplantation Is an Independent Prognostic Factor for Survival Outcome in Patients with Multiple Myeloma

We retrospectively analyzed multiple myeloma (MM) patients who underwent autologous stem cell transplantation (ASCT) without maintenance therapy to assess the impact of recovery of normal immunoglobulin (Ig) on clinical outcomes. The recovery of polyclonal Ig was defined as normalization of all values of serum IgG, IgA, and IgM 1 year after ASCT. Among 50 patients, 26 patients showed polyclonal Ig recovery; 14 patients were in ≥complete response (CR) and 12 remained in non-CR after ASCT. The patients with Ig recovery exhibited a significantly better progression-free survival (PFS, median, 46.8 vs 26.7 months, = 0.0071) and overall survival (OS, median, not reached vs 65.3 months, < 0.00001) compared with those without Ig recovery. The survival benefits of Ig recovery were similarly observed in ≥CR patients (median OS, not reached vs 80.5 months, = 0.061) and non-CR patients (median OS, not reached vs 53.2 months, = 0.00016). Multivariate analysis revealed that non-CR and not all Ig recovery were independent prognostic factors for PFS (HR, 4.284, 95%CI (1.868-9.826), = 0.00059; and HR, 2.804, 95%CI (1.334-5.896), = 0.0065, respectively) and also for OS (HR, 8.245, 95%CI (1.528-44.47), = 0.014; and HR, 36.55, 95%CI (3.942-338.8), = 0.0015, respectively). Therefore, in addition to the depth of response, the recovery of polyclonal Ig after ASCT is a useful indicator especially for long-term outcome and might be considered to prevent overtreatment with maintenance therapy in transplanted patients with MM.


芽球様の形態を示した肝脾型T細胞リンパ腫の一症例

芽球様の形態を示した肝脾型T細胞リンパ腫の一症例


PD-L1 upregulation in myeloma cells by panobinostat in combination with interferon-γ.

gene silencing abolished the PD-L1 upregulation by panobinostat and IFN-γ in combination, indicating a critical role for STAT1. These results suggest that panobinostat enhances PD-L1 expression by facilitating the IFN-γ-STAT1 pathway in a ligand-dependent manner in MM cells with ambient IFN-γ. PD-L1 upregulation should be taken into account when combining immunotherapies with panobinostat.


De novo CD 20-negative diffuse large B-cell lymphoma developed with sustained fever and markedly high C-reactive protein level

不明熱と著明な高CRP血症で発症したde novo CD20陰性びまん性大細胞型B細胞リンパ腫の1例

A 68-year-old woman presented with sustained fever for more than 1 month and admitted due to hematemesis and systemic edema. Computed tomography scan revealed swelling of the cervical, paraaortic lymph nodes. Blood test results showed severe anemia, elevation of white blood cell count, elevation of liver enzyme and coagulopathy with high C-reactive protein. Biopsy of the right cervical lymph node showed proliferation of abnormal lymphoid cells with necrosis and hemorrhage, which are positive for CD79α, CD30, MUM-1, and bcl-6 and negative for CD20, CD5, CD10, ALK, CD38, CD138, and EBER. Gene rearrangement of immunoglobulin heavy chain was detected in tumor cells. Bone marrow aspiration showed tumor involvement. The patient was diagnosed with de novo CD20-negative diffuse large B-cell lymphoma(DLBCL)stage IV B. Reduced CHOP therapy was performed under artificial respiration due to pulmonary edema and takotsubo cardiomyopathy. Although her general condition and high CRP levels temporarily improved, she died 47 days after admission due to rapid relapse. De novo CD20-negative DLBCL was rare and presented with high CRP levels and rapid progression, and was thought to be clinically different from the existing DLBCL. It is imperative to elucidate molecular pathophysiology and establish new treatment strategy for de novo CD20-negative DLBCL.


Class 1 HDAC and HDAC6 inhibition inversely regulates CD38 induction in myeloma cells via interferon-α and ATRA.


Pim-2 is a critical target for treatment of osteoclastogenesis enhanced in myeloma.


Unique anti-myeloma activity by thiazolidine-2,4-dione compounds with Pim inhibiting activity.

Proviral Integrations of Moloney virus 2 (PIM2) is overexpressed in multiple myeloma (MM) cells, and regarded as an important therapeutic target. Here, we aimed to validate the therapeutic efficacy of different types of PIM inhibitors against MM cells for their possible clinical application. Intriguingly, the thiazolidine-2,4-dione-family compounds SMI-16a and SMI-4a reduced PIM2 protein levels and impaired MM cell survival preferentially in acidic conditions, in contrast to other types of PIM inhibitors, including AZD1208, CX-6258 and PIM447. SMI-16a also suppressed the drug efflux function of breast cancer resistance protein, minimized the sizes of side populations and reduced in vitro colony-forming capacity and in vivo tumourigenic activity in MM cells, suggesting impairment of their clonogenic capacity. PIM2 is known to be subject to ubiquitination-independent proteasomal degradation. Consistent with this, the proteasome inhibitors bortezomib and carfilzomib increased PIM2 protein levels in MM cells without affecting its mRNA levels. However, SMI-16a mitigated the PIM2 protein increase and cooperatively enhanced anti-MM effects in combination with carfilzomib. Collectively, the thiazolidine-2,4-dione-family compounds SMI-16a and SMI-4a uniquely reduce PIM2 protein in MM cells, which may contribute to their profound efficacy in addition to their immediate kinase inhibition. Their combination with proteasome inhibitors is envisioned.


Development of adult T-cell leukemia/lymphoma during immunosuppressive Therapy for human T-cell leukemia virus type 1 associated arthropathy

リウマチ様関節炎に対する免疫抑制療法中に発症した成人T細胞性白血病/リンパ腫の1例

A 64-year-old woman presented with lower leg edema, fever, and bilateral joint pain, involving the wrists, fingers, and knees, in April 201X. Serological test results were negative for rheumatoid factor, antinuclear antibody, and anti-cyclic citrullinated peptide antibody. A diagnosis of remitting seronegative symmetrical synovitis with pitting edema syndrome, a type of seronegative rheumatoid arthritis, was made and prednisolone was administered. The joint pain was refractory to prednisolone therapy. In February, 201X+2, the patient presented with right cervical lymphadenopathy. The CT scan revealed swelling of the cervical, axillary, and inguinal lymph nodes bilaterally and rapidly enlarged. In April, 18F-fluorodeoxyglucose PET/CT scan showed an abnormal collection in the enlarged lymph nodes. The patient subsequently developed hoarseness with dyspnea and attended our department. Blood test results showed high levels of lactate dehydrogenase (547U/L) and soluble interleukin‐2 receptor (34200 IU/L) and were positive for anti-human T-cell leukemia virus type1 (HTLV‐1) antibody. Biopsy of the right cervical lymph node showed proliferation of abnormal lymphoid cells positive for CD3, CD4, and CD25 and negative for CD7. Monoclonal integration of HTLV‐1 proviral DNA was detected in the lymph node. A diagnosis of adult T-cell leukemia/lymphoma (ATLL), lymphoma type was made. The pain involving multiple joints was attributed to HTLV‐1associated arthropathy. Immunosuppressive therapy for HTLV‐1 carrier status may have played a role in the development of ATLL.


Effective impairment of myeloma cells and their progenitors by hyperthermia.

Multiple myeloma (MM) remains incurable, and MM-initiating cells or MM progenitors are considered to contribute to disease relapse through their drug-resistant nature. In order to improve the therapeutic efficacy for MM, we recently developed novel superparamagnetic nanoparticles which selectively accumulate in MM tumors and extirpate them by heat generated with magnetic resonance. We here aimed to clarify the therapeutic effects on MM cells and their progenitors by hyperthermia. Heat treatment at 43°C time-dependently induced MM cell death. The treatment upregulated endoplasmic reticulum (ER) stress mediators, ATF4 and CHOP, while reducing the protein levels of Pim-2, IRF4, c-Myc and Mcl-1. Combination with the proteasome inhibitor bortezomib further enhanced ER stress to potentiate MM cell death. The Pim inhibitor SMI-16a also enhanced the reduction of the Pim-2-driven survival factors, IRF4 and c-Myc, in combination with the heat treatment. The heat treatment almost completely eradicated "side population" fractions in RPMI8226 and KMS-11 cells and suppressed their clonogenic capacity as determined by colony formation and tumorigenic capacity in SCID mice. These results collectively demonstrated that hyperthermia is able to impair clonogenic drug-resistant fractions of MM cells and enhance their susceptibility to chemotherapeutic drugs.


TAK1 inhibition subverts the osteoclastogenic action of TRAIL while potentiating its antimyeloma effects.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) agonists induce tumor-specific apoptosis indicating that they may be an attractive therapeutic strategy against cancers, including multiple myeloma (MM). Osteoclastogenesis is highly induced in MM, which in turn enhances MM growth, thereby forming a vicious cycle between MM tumor expansion and bone destruction. However, the effects of TRAIL on MM-enhanced osteoclastogenesis remain largely unknown. Here, we show that TRAIL induced apoptosis in MM cells, but not in osteoclasts (OCs), and that it rather facilitated receptor activator of NF-B ligand-induced osteoclastogenesis along with upregulation of cellular FLICE inhibitory protein (c-FLIP). TRAIL did not induce death-inducing signaling complex formation in OCs, but formed secondary complex (complex II) with the phosphorylation of transforming growth factor -activated kinase-1 (TAK1), and thus activated NF-B signaling. c-FLIP knockdown abolished complex II formation, thus permitting TRAIL induction of OC cell death. The TAK1 inhibitor LLZ1640-2 abrogated the TRAIL-induced c-FLIP upregulation and NF-B activation, and triggered TRAIL-induced caspase-8 activation and cell death in OCs. Interestingly, the TRAIL-induced caspase-8 activation caused enzymatic degradation of the transcription factor Sp1 to noticeably reduce c-FLIP expression, which further sensitized OCs to TRAIL-induced apoptosis. Furthermore, the TAK1 inhibition induced antiosteoclastogenic activity by TRAIL even in cocultures with MM cells while potentiating TRAIL's anti-MM effects. These results demonstrated that osteoclastic lineage cells use TRAIL for their differentiation and activation through tilting caspase-8-dependent apoptosis toward NF-B activation, and that TAK1 inhibition subverts TRAIL-mediated NF-B activation to resume TRAIL-induced apoptosis in OCs while further enhancing MM cell death in combination with TRAIL.


Synergistic targeting of Sp1, a critical transcription factor for myeloma cell growth and survival, by panobinostat and proteasome inhibitors.

Panobinostat, a pan-deacetylase inhibitor, synergistically elicits cytotoxic activity against myeloma (MM) cells in combination with the proteasome inhibitor bortezomib. Because precise mechanisms for panobinostat's anti-MM action still remain elusive, we aimed to clarify the mechanisms of anti-MM effects of panobinostat and its synergism with proteasome inhibitors. Although the transcription factor Sp1 was overexpressed in MM cells, the Sp1 inhibitor terameprocol induced MM cell death in parallel with reduction of IRF4 and cMyc. Panobinostat induced activation of caspase-8, which was inversely correlated with reduction of Sp1 protein levels in MM cells. The panobinostat-mediated effects were further potentiated to effectively induce MM cell death in combination with bortezomib or carfilzomib even at suboptimal concentrations as a single agent. Addition of the caspase-8 inhibitor z-IETD-FMK abolished the Sp1 reduction not only by panobinostat alone but also by its combination with bortezomib, suggesting caspase-8-mediated Sp1 degradation. The synergistic Sp1 reduction markedly suppressed Sp1-driven prosurvival factors, IRF4 and cMyc. Besides, the combinatory treatment reduced HDAC1, another Sp1 target, in MM cells, which may potentiate HDAC inhibition. Collectively, caspase-8-mediated post-translational Sp1 degradation appears to be among major mechanisms for synergistic anti-MM effects of panobinostat and proteasome inhibitors in combination.


A vicious cycle between acid sensing and survival signaling in myeloma cells: acid-induced epigenetic alteration.

Myeloma (MM) cells and osteoclasts are mutually interacted to enhance MM growth while creating acidic bone lesions. Here, we explored acid sensing of MM cells and its role in MM cell response to acidic conditions. Acidic conditions activated the PI3K-Akt signaling in MM cells while upregulating the pH sensor transient receptor potential cation channel subfamily V member 1 (TRPV1) in a manner inhibitable by PI3K inhibition. The acid-activated PI3K-Akt signaling facilitated the nuclear localization of the transcription factor Sp1 to trigger the expression of its target genes, including TRPV1 and HDAC1. Consistently, histone deacetylation was enhanced in MM cells in acidic conditions, while repressing a wide variety of genes, including DR4. Indeed, acidic conditions deacetylated histone H3K9 in a DR4 gene promoter and curtailed DR4 expression in MM cells. However, inhibition of HDAC as well as either Sp1 or PI3K was able to restore DR4 expression in MM cells suppressed in acidic conditions. These results collectively demonstrate that acid activates the TRPV1-PI3K-Akt-Sp1 signaling in MM cells while inducing HDAC-mediated gene repression, and suggest that a positive feedback loop between acid sensing and the PI3K-Akt signaling is formed in MM cells, leading to MM cell response to acidic bone lesions.


Expansion of Th1-like V9V2T cells by new-generation IMiDs, lenalidomide and pomalidomide, in combination with zoledronic acid.


Human immunodeficiency virus-positive secondary syphilis mimicking cutaneous T-cell lymphoma.

Malignant syphilis or lues maligna is a severe form of secondary syphilis that was commonly reported in the pre-antibiotic era, and has now reemerged with the advent of the human immunodeficiency virus (HIV) epidemic. However, the characteristic histopathological findings of malignant syphilis remain controversial. The aim of this case report was to clarify the clinical and histopathological findings of HIV-positive malignant secondary syphilis. A Japanese man in his forties complained of fever, skin lesions, headache, and myalgia without lymphadenopathy during the previous 4 weeks. The skin lesions manifested as erythematous, nonhealing, ulcerated papules scattered on his trunk, extremities, palm, and face. Although the skin lesions were suspected to be cutaneous T-cell lymphomas on histological analyses, they lacked T-cell receptor Jγ rearrangement; moreover, immunohistochemical analyses confirmed the presence of spirochetes. The patient was administered antibiotics and anti-retroviral therapy, which dramatically improved the symptoms. On the basis of these observations of the skin lesions, we finally diagnosed the patient with HIV-associated secondary syphilis that mimicked cutaneous T-cell lymphoma. The patient's systemic CD4+ lymphocyte count was very low, and the infiltrate was almost exclusively composed of CD8+ atypical lymphocytes; therefore, the condition was easily misdiagnosed as cutaneous lymphoma. Although the abundance of plasma cells is a good indicator of malignant syphilis on skin histological analyses, in some cases, the plasma cell count may be very low. Therefore, a diagnosis of malignant secondary syphilis should be considered before making a diagnosis of primary cutaneous peripheral T-cell lymphoma or lymphoma associated with HIV infection.


Susceptibility to bendamustine considerably varies among myeloma cells, but is enhanced in acidic conditions


Induction of endoplasmic reticulum stress by bortezomib sensitizes myeloma cells to DR5-mediated cell death

TNF-related apoptosis-including ligand/Apo2 (TRAIL)-mediated immunotherapy is an attractive anti-tumor modality with high tumor specificity. In order to improve its therapeutic efficacy, we further need to implement a novel maneuver for sensitization of malignant cells to TRAIL. Bortezomib (BTZ), a novel anti-myeloma (MM) agent, potently induces endoplasmic reticulum (ER) stress to cause apoptosis. Here, we explored the roles of BTZ in the cytotoxicity of anti-TRAIL receptor agonistic antibodies against MM cells with special reference to ER stress. BTZ enhanced the expression of death receptor 5 (DR5) but not DR4 in MM cells at surface protein as well as mRNA levels. However, the DR5 expression was not affected by BTZ without ER stress induction in MM cells with a point mutation in a BTZ-binding proteasome β5 subunit. Tunicamycin, an ER stress inducer, was able to enhance the DR5 expression even in the BTZ-resistant MM cells, suggesting the role of ER stress in up-regulation of DR5 expression. Interestingly, BTZ facilitated extrinsic caspase-mediated apoptosis by anti-DR5 agonistic antibody in MM cells along with reducing c-FLICE-like interleukin protein, a caspase 8 inhibitor. These results suggest that BTZ enhances DR5 expression and its downstream apoptotic signaling through ER stress to sensitize MM cells to TRAIL-mediated immunotherapy.


Successful treatment of refractory severe aplastic anemia with bone marrow transplantation from a genetically identical twin

同系骨髄移植が著効した最重症再生不良性貧血の1例

Aplastic anemia is a bone marrow failure caused by severely curtailed hematopoietic stem cells (HSCs) and dysregulation of ambient immune cells. Immumo-suppressive conditioning followed by allogeneic HSC transplantation is currently a mainstay in treatment for patients at a younger age or those refractory to conventional immunosuppressive remedies. Syngeneic HSC transplantation appears to be promising, but has been very rarely performed ; therefore, its impact on a long-term outcome as well as the best preparative measures for HSC engraftment and immune amelioration are still largely unknown. Here, we reported a successful and beneficial syngeneic HSC transplantation for a refractory case with very severe aplastic anemia. A 30-year-old female presented high fever after tooth extraction, and was diagnosed with very severe aplastic anemia. Cyclosporine and anti-thymocyte globulin were initiated, but showed no hematological effects. After obtaining an informed consent, she underwent bone marrow transplantation from a genetically identical twin following an non-myeloablative conditioning regimen consisted of cyclophosphamide (750mg/m2, 4 days), fludarabine phosphate (25mg/m2, 4 days). Cyclosporine was given for acute GvHD prophylaxis. Her neutrophils recovered over 500/μl on 12 days after the transplantation, and her blood counts have been maintained in a normal range over 7 years thereafter. Although a fate of HSCs from a genetically identical twin and an immune response of ambient cells in the bone marrow in recipients remains largely unknown, from the present case and previously reported cases, we dare to recommend immunoablative conditioning and acute GvHD prophylaxis in syngeneic HSC transplantation for a refractory case with aplastic anemia for better engraftment and sustained onward recovery of hematopoiesis.


Pim-2 kinase is an important target of treatment for tumor progression and bone loss in myeloma.

Pim-2 kinase is overexpressed in multiple myeloma (MM) cells to enhance their growth and survival, and regarded as a novel therapeutic target in MM. However, the impact of Pim-2 inhibition on bone disease in MM remains unknown. We demonstrated here that Pim-2 expression was also upregulated in bone marrow stromal cells and MC3T3-E1 preosteoblastic cells in the presence of cytokines known as the inhibitors of osteoblastogenesis in MM, including interleukin-3 (IL-3), IL-7, tumor necrosis factor-, transforming growth factor- (TGF-) and activin A, as well as MM cell conditioned media. The enforced expression of Pim-2 abrogated in vitro osteoblastogenesis by BMP-2, which suggested Pim-2 as a negative regulator for osteoblastogenesis. Treatment with Pim-2 short-interference RNA as well as the Pim inhibitor SMI-16a successfully restored osteoblastogenesis suppressed by all the above inhibitory factors and MM cells. The SMI-16a treatment potentiated BMP-2-mediated anabolic signaling while suppressing TGF- signaling. Furthermore, treatment with the newly synthesized thiazolidine-2,4-dione congener, 12a-OH, as well as its prototypic SMI-16a effectively prevented bone destruction while suppressing MM tumor growth in MM animal models. Thus, Pim-2 may have a pivotal role in tumor progression and bone loss in MM, and Pim-2 inhibition may become an important therapeutic strategy to target the MM cell-bone marrow interaction.Leukemia advance online publication, 30 May 2014; doi:10.1038/leu.2014.147.


Combination with a Defucosylated Anti-HM1.24 Monoclonal Antibody plus Lenalidomide Induces Marked ADCC against Myeloma Cells and Their Progenitors

The immunomodulatory drug lenalidomide (Len) has drawn attention to potentiate antibody-dependent cellular cytotoxicity (ADCC)-mediated immunotherapies. We developed the defucosylated version (YB-AHM) of humanized monoclonal antibody against HM1.24 (CD317) overexpressed in multiple myeloma (MM) cells. In this study, we evaluated ADCC by YB-AHM and Len in combination against MM cells and their progenitors. YB-AHM was able to selectively kill via ADCC MM cells in bone marrow samples from patients with MM with low effector/target ratios, which was further enhanced by treatment with Len. Interestingly, Len also up-regulated HM1.24 expression on MM cells in an effector-dependent manner. HM1.24 was found to be highly expressed in a drug-resistant clonogenic "side population" in MM cells; and this combinatory treatment successfully reduced SP fractions in RPMI 8226 and KMS-11 cells in the presence of effector cells, and suppressed a clonogenic potential of MM cells in colony-forming assays. Collectively, the present study suggests that YB-AHM and Len in combination may become an effective therapeutic strategy in MM, warranting further study to target drug-resistant MM clonogenic cells.


Activating transcription factor 4, an ER stress mediator, is required for, but exce ssive ER stress suppresses osteoblastogenesis by bortezomib.

Endoplasmic reticulum (ER) stress is induced in matrix-producing osteoblasts and plays an essential role in osteoblastogenesis. Although the bone anabolic activity of proteasome inhibitors has been demonstrated, the roles of ER stress induced by proteasome inhibition in osteoblastogenesis remain largely unknown. Here we show that bortezomib translationally increases protein levels of activating transcription factor 4 (ATF4), a downstream mediator of ER stress, in bone marrow stromal cells and MC3T3-E1 preosteoblastic cells. The suppression of ATF4 expression by siRNA abrogated osteocalcin expression and mineralized nodule formation by MC3T3-E1 cells induced by bortezomib, indicating a critical role for ATF4 in bortezomib-mediated osteoblastogenesis. However, bortezomib at 20 nM or higher abolished the mineralized nodule formation along with reductions in the expression of osteoblastogenesis mediators β-catenin and Osterix. Furthermore, at 50 nM, bortezomib induced the expression of C/EBP homologous protein (CHOP), suggesting activation of the ATF4-CHOP pro-apoptotic pathway. These results suggest that a low dose of bortezomib induces osteogenic activity, but that, in contrast, excessive ER stress caused by bortezomib at higher doses hampers osteoblastogenesis. Therefore, dosing schedules for proteasome inhibitors warrant further study to maximize anabolic actions without compromising anti-MM activity in patients with multiple myeloma (MM).


皮膚ランダム生検が診断に有用であった血管内リンパ腫の一例

皮膚ランダム生検が診断に有用であった血管内リンパ腫の一例

A62‐year‐old woman was referred to our hospital for further examination of fever of unknownorigin, splenomegaly and pancytopenia. On admission, she had persistent fever and psychologicalsymptoms. Blood examination showed pancytopenia and elevated level of LDH, soluble IL‐2receptorand ferritin. Computed tomography showed multiple low density areas in the spleen, but no systemiclymphadenopathy. In magnetic resonance imaging of the pons, a low and high intensity area onT1‐and T2‐weighted image, respectively, was detected. Taken together these findings, she wassuspected to have hepatosplentic T-cell lymphoma or intravascular large B-cell lymphoma. To makea definite diagnosis, random skin biopsy was performed. Immunohistochemical stainings revealedthe massive infiltration of CD20‐and CD79α‐positive large lymphoid cells inside the vessels, whichyielded the diagnosis of intravascular large B-cell lymphoma.


KRN5500, a spicamycin derivative, exerts anti-myeloma effects through impairing both myeloma cells and osteoclasts.

The spicamycin analogue KRN5500 alters glycoprotein processing and induces damage in the endoplasmic reticulum (ER)-Golgi apparatus in cancer cells. In the present study, we explored the cytotoxic effects of KRN5500 on multiple myeloma (MM) cells and the bone marrow microenvironment with special reference to ER stress. Cell proliferation assay showed that KRN5500 induced G1 arrest and apoptosis in MM cells in a time- and dose-dependent manner. KRN5500 enhanced ER stress independently of caspase activation in MM cells. This cell death was observed even in the presence of bone marrow stroma cells or osteoclasts. Notably, KRN5500 induced cell death also in osteoclasts. In vivo effects of KRN5500 were evaluated using two xenograft models established in severe combined immunodeficient (SCID) mice by either subcutaneous injection of RPMI 8226 cells or intra-bone injection of INA-6 cells to subcutaneously implanted rabbit bones (SCID-rab model). KRN5500 significantly inhibited tumour growth in both animal models, and decreased the number of osteoclasts, which resulted in prevention of bone destruction in the SCID-rab model. These results suggest that KRN5500 exerts anti-MM effects through impairing both MM cells and osteoclasts. Therefore, this unique mechanism of KRN5500 might be a useful therapeutic option in patients with MM.


Targeting myeloma-osteoclast interaction with V9V2 T cells.

Multiple myeloma (MM) cells stimulate osteoclastogenesis, and osteoclasts (OCs) in turn enhance MM growth and drug resistance, resulting in a vicious cycle. V9V2 T cells exert potent anti-tumor effects, making T cell-based immunotherapies using these cells attractive candidates for currently incurable malignancies, such as MM. However, the impact of such treatments on the MM-OC interaction is largely unknown. We demonstrate here that V9V2 T cells expanded by zoledronic acid and IL-2 exerted potent cytotoxic effects on both MM cells and OCs, even in coculture settings, but showed no such effect on bone marrow stromal cells. V9V2 T cells marginally affected colony formation from normal hematopoietic progenitors, and furthermore migrated toward osteopontin and MIP-1, factors produced by the MM-OC interaction. These results suggest that V9V2 T cells expanded by zoledronic acid and IL-2 are able to migrate to MM bone lesions and preferentially target OCs as well as MM cells, thereby inhibiting both tumor expansion and bone destruction.


The serine/threonine kinase Pim-2 is a novel anti-apoptotic mediator in myeloma cells.

Bone marrow stromal cells (BMSCs) and osteoclasts (OCs) confer multiple myeloma (MM) cell survival through elaborating factors. We demonstrate herein that IL-6 and TNF family cytokines, TNF, BAFF and APRIL, but not IGF-1 cooperatively enhance the expression of the serine/threonine kinase Pim-2 in MM cells. BMSCs and OCs upregulate Pim-2 expression in MM cells largely via the IL-6/STAT3 and NF-B pathway, respectively. Pim-2 short interfering RNA reduces MM cell viability in cocultures with BMSCs or OCs. Thus, upregulation of Pim-2 appears to be a novel anti-apoptotic mechanism for MM cell survival. Interestingly, the mammalian target of rapamycin inhibitor rapamycin further suppresses the MM cell viability in combination with the Pim-2 silencing. The Pim inhibitor (Z)-5-(4-propoxybenzylidene) thiazolidine-2, 4-dione and the PI3K inhibitor LY294002 cooperatively enhance MM cell death. The Pim inhibitor suppresses 4E-BP1 phosphorylation along with the reduction of Mcl-1 and c-Myc. Pim-2 may therefore become a new target for MM treatment.Leukemia advance online publication, 8 April 2011; doi:10.1038/leu.2011.60.