Multiple myeloma (MM) is a cancer characterized by the expansion of plasma cells in the bone marrow. Survival times of patients with MM have increased due to the development of novel therapeutic ...agents. We herein highlight three MM cases that had a poor prognosis despite treatment with novel therapeutic agents. Of note, all patients presented with hyperammonemia that led to a consciousness disorder. The outcome for patients with MM showing high levels of serum ammonia continues to be poor, even with the use of novel therapies. For such patients showing a consciousness disorder, hyperammonemia should be considered as a possible cause.
Aberrant reactivation of hedgehog (Hh) signaling has been described in a wide variety of human cancers and in cancer stem cells. However, the contribution of Hh signaling to leukemic cell regulation ...has remained unclear. In this study, we assessed the possibility that Hh pathway activation contributes to the survival and drug resistance of cluster of differentiation (CD)34+ leukemia cells. Hh signaling in leukemic cell lines and primary leukemic cells was screened by reverse transcription – polymerase chain reaction (RT‐PCR) and a Hh signaling reporter assay. We found that Hh signaling is active in several human acute myeloid leukemia (AML) cells, especially primary CD34+ leukemic cells and cytokine‐responsive CD34+ cell lines such as Kasumi‐1, Kasumi‐3 and TF‐1. These CD34+ cells express the downstream effectors glioma‐associated oncogene homolog (GLI)1 or GLI2, indicative of active Hh signaling. Moreover, inhibition of Hh signaling with the naturally derived Smoothened antagonist cyclopamine, endogenous Hh inhibitor hedgehog‐interacting protein or anti‐hedgehog neutralizing antibody induced apoptosis after 48 h of exposure, although these CD34+ cell lines exhibited resistance to cytarabine (Ara‐C). In contrast, cyclopamine failed to affect growth or survival in U937 and HL‐60 cell lines that lack expression of Hh receptor components, confirming that the effect of Hh inhibition is specific. Furthermore, combination with 10 µM cyclopamine significantly reduced drug resistance of CD34+ cell lines and primary CD34+ leukemic cells to Ara‐C. These results suggest that aberrant Hh pathway activation is a feature of some CD34+ myeloid leukemic cells and Hh inhibitors may have a therapeutic role in the treatment of AML. (Cancer Sci 2009; 100: 948–955)
Isatuximab, an anti‐CD38 monoclonal antibody, targets cells that strongly express CD38 including malignant plasma cells. This open‐label, single‐arm, multicenter, phase 1/2 trial investigated the ...tolerability/safety and efficacy of isatuximab monotherapy in Japanese patients with heavily pretreated, relapsed/refractory multiple myeloma (RRMM). In Phase 1, patients were sequentially assigned to receive isatuximab once weekly (QW) in cycle 1 (4 weeks) and every 2 weeks (Q2W) in subsequent cycles. Cohort 1 (n = 3) received 10 mg/kg QW/Q2W; cohort 2 (n = 5) received 20 mg/kg QW/Q2W. No dose‐limiting toxicities occurred; the recommended dose for the single‐arm phase 2 study (n = 28) was 20 mg/kg QW/Q2W. The overall safety profile was consistent with the current knowledge of isatuximab. The most common adverse events were infusion reactions (42.9%; 12/28); all were grade 1/2 and generally occurred during the first infusion. The overall response rate with 20 mg/kg QW/Q2W isatuximab was 36.4% (12/33); patients with high‐risk cytogenetic abnormalities had comparable results. In phase 2, the median progression‐free survival was 4.7 (95% confidence interval, 3.75 to not reached) months. Median overall survival was not reached. Isatuximab monotherapy was well tolerated and effective in patients with heavily pretreated RRMM including high‐risk cytogenetic patients. This trial is registered at ClinicalTrials.gov as NCT02812706.
This open‐label, single‐arm, multicenter phase 1/2 trial investigated the tolerability/safety and efficacy of isatuximab monotherapy in Japanese patients with heavily pretreated, relapsed/refractory multiple myeloma (RRMM). The results demonstrated that isatuximab monotherapy was well tolerated and effective in patients with heavily pretreated RRMM, including high‐risk cytogenetic patients.
An activated AKT pathway underlies the pathogenesis of soft tissue sarcoma (STS), with over-expressed phosphorylated AKT (p-AKT) correlating with a poor prognosis in a subset of STS cases. Recently, ...eribulin, a microtubule dynamics inhibitor, has demonstrated efficacy and is approved in patients with advanced/metastatic liposarcoma and breast cancer. However, mechanisms of eribulin resistance and/or insensitivity remain largely unknown. In this study, we demonstrated that an increased p-AKT level was associated with eribulin resistance in STS cells. We found a combination of eribulin with the AKT inhibitor, MK-2206, synergistically inhibited STS cell growth in vivo as well as in vitro. Mechanistically, eribulin plus MK-2206 induced G1 or G2/M arrest by down-regulating cyclin-dependent kinases, cyclins and cdc2, followed by caspase-dependent apoptosis in STS cells. Our findings demonstrate the significance of p-AKT signaling for eribulin-resistance in STS cells and provide a rationale for the development of an AKT inhibitor in combination with eribulin to treat patients with STS.
SMARCA4‐deficient thoracic sarcoma (SMARCA4‐DTS) is a new clinical entity characterized by SMARCA4 inactivation and has a dismal prognosis because of rapid growth. Effective treatments for ...SMARCA4‐DTS have not yet been developed. Most recently, anti‐programmed cell death 1 receptor (PD‐1) blockade has been effective for SMARCA4‐deficient lung cancer and malignant rhabdoid tumor‐like tumors. Here, we describe a patient with SMARCA4‐DTC who experienced a marked response to the administration of pembrolizumab. A 70‐year‐old female was referred to our department for treatment of SMARCA4‐DTC. Positron emission tomography‐computed tomography had revealed a left mediastinal tumor, peritoneal dissemination and multiple cutaneous metastases at diagnosis. Immunohistochemical analyses revealed 60% of tumor cells expressed programmed cell death ligand 1 (PD‐L1). The patient was given pembrolizumab as first‐line treatment. Pembrolizumab suppressed tumor growth dramatically, with only one dose leading to a partial response. Our case suggests the immunohistochemical analysis of PD‐L1 expression be undertaken for patients with SMARCA4‐DTS and that pembrolizumab treatment may be a promising strategy for PD‐L1‐positive SMARCA4‐DTS.
The failure of normal hematopoiesis is observed in myeloid neoplasms. However, the precise mechanisms governing the replacement of normal hematopoietic stem cells in their niche by myeloid neoplasm ...stem cells have not yet been clarified. Primary acute myeloid leukemia and myelodysplastic syndrome cells induced aberrant expression of multiple hematopoietic factors including Jagged-1, stem cell factor and angiopoietin-1 in mesenchymal stem cells even in non-contact conditions, and this abnormality was reverted by extracellular vesicle inhibition. Importantly, the transfer of myeloid neoplasm-derived extracellular vesicles reduced the hematopoietic supportive capacity of mesenchymal stem cells. Analysis of extracellular vesicle microRNA indicated that several species, including miR-7977 from acute myeloid leukemia cells, were higher than those from normal CD34(+)cells. Remarkably, the copy number of miR-7977 in bone marrow interstitial fluid was elevated not only in acute myeloid leukemia, but also in myelodysplastic syndrome, as compared with lymphoma without bone marrow localization. The transfection of the miR-7977 mimic reduced the expression of the posttranscriptional regulator, poly(rC) binding protein 1, in mesenchymal stem cells. Moreover, the miR-7977 mimic induced aberrant reduction of hematopoietic growth factors in mesenchymal stem cells, resulting in decreased hematopoietic-supporting capacity of bone marrow CD34(+)cells. Furthermore, the reduction of hematopoietic growth factors including Jagged-1, stem cell factor and angiopoietin-1 were reverted by target protection of poly(rC) binding protein 1, suggesting that poly(rC) binding protein 1 could be involved in the stabilization of several growth factors. Thus, miR-7977 in extracellular vesicles may be a critical factor that induces failure of normal hematopoiesis via poly(rC) binding protein 1 suppression.
Extramedullary (EM) relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute myeloid leukemia (AML) is rare and causes systemic relapse. Consequently, the prognosis is ...very poor because limited treatment is feasible in post-transplant patients. The efficacy and safety of venetoclax (VEN), a newly developed oral inhibitor of B-cell leukemia/lymphoma-2, plus azacytidine (AZA) in patients newly diagnosed with AML who are ineligible for intensive chemotherapy have been reported. We report a case in which VEN + AZA salvage treatment following radiation therapy and donor lymphocyte infusion afforded promising results in a patient with AML who showed post-allo-HSCT EM relapse.
We and others have demonstrated that various abnormalities of the bone marrow (BM) mesenchymal stromal cells (MSCs) such as aberrant cytokine expression, abnormal hedgehog signaling, and impaired ...miRNA biogenesis are observed in patients with acute myeloid leukemia (AML). However, underlying mechanisms to induce the dysfunction of BM MSCs have not yet been clarified. We previously showed that AML cells release abundant exosomal miR-7977, which, in turn, enters BM mesenchymal stromal cells (MSCs). However, the precise function of miR-7977 is not known. In this study, we performed transduction of a miR-7977 mimic into MSCs, compared transcriptomes between control-transduced (n = 3) and miR-7977-transduced MSCs (n = 3), and conducted pathway analysis. The array data revealed that the expression of 0.05% of genes was reduced 2-fold and the expression of 0.01% of genes was increased 2-fold. Interestingly, approximately half of these genes possessed a miR-7977 target site, while the other genes did not, suggesting that miR-7977 regulates the gene expression level directly and indirectly. Gene set enrichment analysis showed that the gene sets of Yes-associated protein 1 (YAP1) _up were significantly enriched (p<0.001, q<0.25), suggesting that miR-7977 modulates the Hippo-YAP signaling pathway. Visualization of pathway and network showed that miR-7977 significantly reduced the expression of Hippo core kinase, STK4. miR-7977 inactivated the Hippo-YAP signaling pathway as proven by GFP-tagged YAP nuclear trans localization and TEAD reporter assay. The miR-7977-transduced MSC cell line, HTS-5, showed elevated saturation density and enhanced entry into the cell cycle. These results suggest that miR-7977 is a critical factor that regulates the Hippo-YAP signaling pathway in BM-MSCs and may be involved in the upregulation of leukemia-supporting stroma growth.
•We report a series of SCI patients treated with intravenous infusion of MSCs.•Autologous MSCs cultured with auto-serum were used.•The results document observed functional changes and provide support ...for the safety and tolerability of this procedure.
Although spinal cord injury (SCI) is a major cause of disability, current therapeutic options remain limited. Recent progress in cellular therapy with mesenchymal stem cells (MSCs) has provided improved function in animal models of SCI. We investigated the safety and feasibility of intravenous infusion of MSCs for SCI patients and assessed functional status after MSC infusion.
In this phase 2 study of intravenous infusion of autologous MSCs cultured in auto-serum, a single infusion of MSCs under Good Manufacturing Practice (GMP) production was delivered in 13 SCI patients. In addition to assessing feasibility and safety, neurological function was assessed using the American Spinal Injury Association Impairment Scale (ASIA), International Standards for Neurological and Functional Classification of Spinal Cord (ISCSCI-92). Ability of daily living was assessed using Spinal Cord Independence Measure (SCIM-III). The study protocol was based on advice provided by the Pharmaceuticals and Medical Devices Agency in Japan. The trial was registered with the Japan Medical Association (JMA-IIA00154).
No serious adverse events were associated with MSC injection. There was neurologic improvement based on ASIA grade in 12 of the 13 patients at six months post-MSC infusion. Five of six patients classified as ASIA A prior to MSC infusion improved to ASIA B (3/6) or ASIA C (2/6), two ASIA B patients improved to ASIA C (1/2) or ASIA D (1/2), five ASIA C patients improved and reached a functional status of ASIA D (5/5). Notably, improvement from ASIA C to ASIA D was observed one day following MSC infusion for all five patients. Assessment of both ISCSCI-92, SCIM-III also demonstrated functional improvements at six months after MSC infusion, compared to the scores prior to MSC infusion in all patients.
While we emphasize that this study was unblinded, and does not exclude placebo effects or a contribution of endogenous recovery or observer bias, our observations provide evidence supporting the feasibility, safety and functional improvements of infused MSCs into patients with SCI.