Characteristics of chronic lymphocytic leukemia in Japan: Comprehensive analysis of the CLLRSG-01 study

Chronic lymphocytic leukemia (CLL) is rare in Japan. We conducted the nationwide, prospective observational study CLLRSG-01 to clarify the current state of CLL in Japan and to make accurate international comparisons by preparing naturally air-dried smears like those used in other countries. Of the 201 untreated patients enrolled and evaluated, 119 were diagnosed with CLL and 82 with non-CLL mature B-cell neoplasms, based on the WHO classification. Of the 119 CLL patients, 90 were classified as typical and 29 as atypical according to FAB classification morphology, with the proportion of atypical CLL consistent with reports from other countries. Immunophenotypic analyses by flow cytometry showed that 55% of Japanese CLL patients had a Matutes score of 4 or higher, which is lower than the rate of about 90% in Europeans. Mutated IGHV was identified in 80% of Japanese CLL patients, which is a higher rate than in Western patients. The most frequent IGHV gene was VH3-30 (15%), followed by VH3-23 (12%) and VH4-34 (10%). VH1-69, the most common gene in Western countries, was identified in only one patient. These results indicate that the pattern of immunophenotypes and IGHV gene usage in Japanese CLL patients differs from that in Western patients.

Anti-CD38 antibody isatuximab monotherapy for Japanese individuals with relapsed/refractory multiple myeloma: An update of the phase 1/2 ISLANDs study

The primary analysis of the phase 1/2 ISLANDs study in Japanese individuals with relapsed/refractory multiple myeloma (RRMM) showed that isatuximab monotherapy was well tolerated and effective, even in participants with high-risk cytogenetic abnormalities. Here, we report a prespecified second analysis conducted 20 months after the first dosing of the last participant (ClinicalTrials.gov identifier: NCT02812706). The primary objectives were to evaluate the safety and tolerability of isatuximab in phase 1 and to evaluate the efficacy of isatuximab, including assessment of overall response rate (ORR) at the recommended dose (RD), in phase 2. In phase 1, three participants received isatuximab 10 mg/kg every week (QW) for 4 weeks/cycle followed by every 2 weeks (Q2W) and five participants received 20 mg/kg QW/Q2W. Since no dose-limiting toxicities occurred in phase 1, 20 mg/kg QW/Q2W was identified as the RD for the phase 2 study (n = 28). At the time of data cut-off, three participants (one in phase 1 and two in phase 2) continued to receive isatuximab; disease progression and treatment-related adverse events were the most common reasons for treatment discontinuation. The overall safety profile was consistent with the primary analysis. One death, not related to isatuximab treatment, was reported since the first analysis. The ORR and clinical benefit rate remained unchanged from the primary analysis at 36.4% (95% confidence interval [CI]: 20.4%-54.9%) and 54.5% (95% CI: 36.4%-71.9%), respectively. The median progression-free survival (PFS) was 5.6 months, longer than the median PFS reported in the primary analysis (4.7 months), whereas median overall survival was not reached. Overall, isatuximab 20 mg/kg QW/Q2W had an acceptable safety and tolerability profile and showed promising antitumor activity in Japanese individuals with RRMM.

Outcomes of methotrexate-associated lymphoproliferative disorders in rheumatoid arthritis patients treated with disease-modifying anti-rheumatic drugs

Recently, the use of targeted synthetic or biological disease-modifying anti-rheumatic drugs (ts/bDMARDs) in addition to conventional synthetic (cs)DMARDs including methotrexate (MTX) for rheumatoid arthritis (RA) has increased. However, whether ts/bDMARDs are associated with the development and clinicopathological features of MTX-associated lymphoproliferative disorder (MTX-LPD) in patients with RA remains unknown. Therefore, we evaluated the clinical outcomes of 121 patients with MTX-LPD. Results showed that prior use of ts/bDMARDs was not associated with the different histopathological subtypes of MTX-LPD. Patients with polymorphic-type LPD had a better event-free survival than those with diffuse large B-cell lymphoma (DLBCL), classical Hodgkin lymphoma and peripheral T-cell lymphoma. The pathological subtype of lymphoma could predict the clinical outcome of MTX-LPD. In patients with DLBCL, the use of tumour necrosis factor-alpha (TNF-α) inhibitors prior to MTX-LPD onset was associated with a higher non-relapse mortality. Further, patients with RA previously treated with Janus kinase (JAK) inhibitors more commonly required chemotherapy than those treated with csDMARDs alone, indicating disease aggressiveness. Hence, special caution should be observed when managing patients with MTX-LPD previously treated with JAK or TNF-α inhibitors for RA.

Isatuximab monotherapy in relapsed/refractory multiple myeloma: A Japanese, multicenter, phase 1/2, safety and efficacy study

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.

Clinicopathological significance of CD79a expression in classic Hodgkin lymphoma

Classic Hodgkin lymphoma (CHL) is a lymphoid neoplasia characterized by the presence of large tumor cells, referred to as Hodgkin and Reed-Sternberg (HRS) cells, originating from B-cells in an inflammatory background. As the clinical significance of B-cell markers has yet to be fully elucidated, this study aimed to clarify the clinicopathological significance of CD79a in 55 patients with CHL. They were immunohistochemically divided into two groups, comprising of 20 CD79a-positive and 35 CD79a-negative patients. There was no significant correlation between CD79a and CD20 expression (r_^s = 0.125, P = 0.362). CD79a-positive patients were significantly older at onset (P = 0.011). There was no significant correlation between CD79a-positivity and clinical stage (P = 0.203), mediastinal involvement (P = 0.399), extranodal involvement (P = 0.749), or laboratory findings, including serum levels of lactate dehydrogenase (P = 1) and soluble interleukin-2 receptor (P = 0.251). There were significant differences in overall survival (OS) (P = 0.005) and progression-free survival (PFS) (P = 0.007) between CD79a-positive and CD79a-negative patients (5-year OS: 64.6% and 90.5%; 5-year PFS: 44.0% and 76.6%, respectively). Five patients in whom the majority (> 80%) of HRS cells expressed CD79a consisted of 4 males and 1 female aged between 52 and 81 years; 4 of them were in a limited clinical stage. We concluded that CD79a-positive CHL may have unique clinicopathological features.

Unsuppressed serum albumin levels may jeopardize the clinical relevance of the international staging system to patients with light chain myeloma

The international staging system (ISS) is the most commonly used risk-stratification system for patients with multiple myeloma (MM) and is determined by serum albumin and β2-microglobulin levels. In the two determinants, β2-microglobulin levels are frequently observed to be elevated in patients with myeloma, particularly in those with renal impairment. In comparison with patients with intact immunoglobulin myeloma, patients with LC myeloma do not necessarily show decreased levels of serum albumin. The clinical impact of ISS in patients with LCMM, in particular the distinction between ISS I and II, may be complicated due to non-decreased levels of serum albumin in both stages. Accordingly, we have attempted to assess clinical relevance of the ISS in patients with LC myeloma. The clinical data of 1899 patients with MM diagnosed between January 2001 and December 2012 were collected from 38 affiliated hospitals of the Japanese Society of Myeloma. Significant difference was not found between stage I (n = 72) and stage II (n = 92) in LC myeloma patients (n = 307). The mean serum albumin concentration of patients with LC myeloma was within the reference range but higher than that of patients with IgG + IgA myeloma (n = 1501), which complicates the distinction between ISS stage I and II myeloma. Patients with LC myeloma had low frequencies of t(4; 14) and high frequency of elevated lactate dehydrogenase, and despite a relevant amount of missing data in our registry (R-ISS stage I; n = 11, stage II; n = 32, and stage III: n = 18), the information included in the R-ISS scoring system seems to be more accurate than ISS to obtain a reliable risk stratification approach in non-ISS stage III LC myeloma patients.

Watch-and-wait policy versus rituximab-combined chemotherapy in Japanese patients with intestinal follicular lymphoma

BACKGROUND AND AIM

Few reports have demonstrated the effectiveness of treatments for intestinal follicular lymphoma (FL) because of the limited number of patients who undergo comprehensive small intestinal examinations. This study compared the efficacy of rituximab-combined chemotherapy in patients with asymptomatic and low tumor burden (LTB) intestinal FL, according to the criteria of the Groupe d'Etude des Lymphomes Folliculaires, with that of a "watch and wait" (W&W) approach.

METHODS

The endoscopic examination for entire gastrointestinal tracts was performed in 29 Japanese patients with intestinal FL. These patients had CD21-positive follicular dendritic cells arranged in a duodenal pattern. In a prospective, two-center, open-label trial, this study evaluated the efficacy of rituximab-combined chemotherapy ([cyclophosphamide, doxorubicin, vincristine, and prednisone] or [cyclophosphamide, vincristine, and prednisone]) and prolonged treatment with rituximab (R-Chemo+prolongedR) in 14 patients and compared their outcomes with those of 15 patients managed with a W&W approach.

RESULTS

Four patients managed with the W&W plan showed worsening macroscopic findings, lesion area enlargement, or clinical stage progression but stayed on this plan because they had LTB and experienced no changes in bowel function. In the R-Chemo+prolongedR group, all patients achieved complete remission; recurrence occurred in one patient, who was subsequently managed with the W&W plan because of LTB. There were no significant differences in progression-free survival between the two groups (P = 0.1045). Overall survival was 100% in both groups.

CONCLUSIONS

The prognoses of patients with asymptomatic intestinal FL and LTB who were managed with a W&W strategy were comparable with those of patients receiving R-Chemo+prolongedR.

[Philadelphia chromosome-positive acute lymphoblastic leukemia complicated by concomitant Achromobacter xylosoxidans and Corynebacterium striatum bacteremia following allogeneic hematopoietic stem cell transplantation]

A 54-year-old woman with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) underwent hematopoietic stem cell transplantation from an HLA-matched sibling. Subsequently, she suffered from chronic graft versus host disease (GvHD) and received medical treatment. Fever developed on day 697 and resulted in a shock state at 10 h after the visit. Achromobacter xylosoxidans was detected in the initial blood culture on day 699. General conditions exacerbated even after the start of meropenem hydrate (MEPM, Meropen^®) administration, with Corynebacterium striatum detected as an additional species in the initial blood culture on day 701. Although vancomycin hydrochloride (VCM, Vancomycin^®) was administered, the conditions did not improve. She died on day 702. Between January 2012 and December 2016, A. xylosoxidans was detected only in nine cases in our hospital, which included five with hematological malignancies and only one (present) with sepsis. At the same time, Corynebacterium species were detected in blood cultures from 39 cases in our hospital, which included 31 with hematological malignancies. Some reports on drug-resistant A. xylosoxidans and C. striatum have been published. Infections with these species may become fatal when complicated by sepsis in immunocompromised patients with hematological malignancies. More cases should be accumulated for detailed investigation.

[Acute leukemia recurring as extramedullary tumors of the ovary following allogeneic hematopoietic stem cell transplantation]

The poor prognosis of extramedullary recurrence of acute leukemia following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a therapeutic challenge, and thus far no effective treatment method has been established. Here, we report two patients who presented with relapsed leukemia as extramedullary tumor in the ovary following allo-HSCT. Case 1: A 23-year-old female underwent unrelated allogeneic bone marrow transplantation during the second remission of acute myeloid leukemia. After 706 days post-transplant, bilateral ovarian tumors were detected during the pelvic ultrasound, and extramedullary recurrence in the bilateral ovaries was subsequently established on right salpingo-oophorectomy and biopsy of the left ovary. Following completed systemic chemotherapy and total body irradiation, the patient underwent unrelated cord blood transplantation (CBT) and remission was maintained without recurrence for 7 years after second transplantation. Case 2: A 49-year-old female underwent unrelated CBT during the second remission of acute lymphocytic leukemia. At 372 days post-transplant, a pelvic tumor was detected by FDG-PET/CT, and extramedullary recurrence in the right ovary was diagnosed on examination of the resected pelvic mass. Chemotherapy and radiation were performed, but the tumor recurred on day 1,027 and the patient died on day 1,603. Extramedullary recurrence of adult acute leukemia as a mass in the ovary following allo-HSCT has been rarely reported. Therefore, further accumulation of related case reports is desired.

Successful haploidentical stem cell transplantation with prophylactic administration of liposomal amphotericin B after invasive pulmonary zygomycosis

A 54-year-old woman with acute myeloid leukemia (AML) achieved complete remission by induction chemotherapy, but developed zygomycosis after consolidation therapy. As zygomycosis could not be cured by liposomal amphotericin B and micafungin, left lower lobectomy was performed. As AML relapsed 7 months after onset, she received haploidentical stem cell transplantation under administration of liposomal amphotericin B. Despite experiencing severe acute graft-versus-host disease, she remains alive with no relapse of either zygomycosis or AML.

Post-allogeneic stem cell transplant extramedullary relapse of acute megakaryoblastic leukemia initially detected by elevated WT1 mRNA levels in peripheral blood

An 18-year-old male was admitted to our hospital for fever, and was diagnosed with acute megakaryoblastic leukemia (AML M7) based on the presence of CD42a and CD61 positive myeloblasts in peripheral blood (PB). Induction chemotherapy at our hospital resulted in complete remission (CR). Subsequently, he underwent unrelated HLA-DR one locus-mismatched allogeneic bone marrow (BM) transplantation. Although CR was maintained without development of graft-versus-host disease (GvHD), the WT1 mRNA level in PB was elevated on post-transplant day 134. As BM aspiration performed 1 week later confirmed maintenance of CR, and because the WT1 mRNA level in BM was not high in comparison with PB, we suspected extramedullary relapse. PET-CT demonstrated a thymic tumor and a gastric tumor with abnormal accumulation of FDG, and biopsy confirmed both to be extramedullary relapse of AML M7. Induction chemotherapy following local radiation therapy achieved a second CR, following which he received HLA haploidentical peripheral blood stem cell transplantation on day 256 after the first transplant. The patient is currently surviving free from both relapse and GvHD. High WT1 mRNA levels in PB as compared with BM should raise suspicion of extramedullary relapse, and PET-CT is very useful for whole body evaluation in such cases.

Prognostic Significance of New-Onset Atrial Fibrillation in Patients With Non-Hodgkin's Lymphoma Treated With Anthracyclines

Cancer therapeutics-related cardiac dysfunction induced by anthracycline is highly problematic, and its early recognition is of importance. Atrial fibrillation (AF) is sometimes seen after anthracycline chemotherapy. We aimed to test whether new-onset AF predicts anthracycline-induced heart failure. We prospectively studied 249 lymphoma patients who received anthracyclines. The patients were followed up with a frequent electrocardiographic examination. Fifteen patients (6%) newly developed AF after the chemotherapy, and during a mean follow-up of 34 months, they had a higher incidence of acute heart failure (40% vs 3.8%; p <0.001) and greater all-cause mortality (60% vs 14.1%; p <0.001) than those without AF. The onset of AF preceded the development of heart failure by a mean of 2.4 months. New-onset AF was independently associated with both acute heart failure (hazard ratio 12.78; p <0.001) and all-cause mortality (hazard ratio 4.77; p <0.001). The cumulative anthracycline dose did not differ between the patients with and without heart failure, yet it was another independent predictor of the mortality. In conclusion, new-onset AF may predict unfavorable outcomes after anthracycline chemotherapy in patients with malignant lymphoma.

The role of "watch and wait" in intestinal follicular lymphoma in rituximab era

OBJECTIVE

There is no consensus regarding the best treatment for intestinal follicular lymphoma (FL). We used "watch and wait" for patients with intestinal FL with low-tumor-burden (LTB) criteria and without mass formation causing bowel obstruction. We investigated the overall survival (OS) and time to treatment required (TTR).

METHODS

Thirty-three intestinal FL patients [clinical stage (CS) I:16, II1:0, II2:7, IV:10; median observation period: 45.5 months, range: 13-110 months] were diagnosed via endoscopy. Detailed clinical and pathological examinations were performed, and neoplastic process behavior was monitored.

RESULTS

All of the 33 patients were WHO grade 1. FL lesions in the digestive tract were found frequently in the second-fourth portion of the duodenum in 91% of the patients; 87% of those patients had lesions in a broader area including the small intestine. Two patients had an enlargement of the area of the lesions and a worsening of the macroscopic findings. Three patients had CS progression; however, these remained within the indication for "watch and wait." Two patients with transformation into diffuse large B-cell lymphoma received rituximab and chemotherapy, which led to complete remission. The OS was 100%. The time to treatment required (TTR) was 49 months in one patient and 37 months in one patient.

CONCLUSION

Intestinal FL in CS I-IV with broad infiltration of the digestive tract meeting the criteria for LTB had a remarkably slow course. This study suggests that "watch and wait" is appropriate for the treatment of LTB intestinal FL even in the era of rituximab.

Survival of multiple myeloma patients aged 65-70 years in the era of novel agents and autologous stem cell transplantation. A multicenter retrospective collaborative study of the Japanese Society of Myeloma and the European Myeloma Network

Novel agents such as thalidomide, lenalidomide and bortezomib have dramatically changed the treatment paradigm of multiple myeloma (MM). However, it is not clear whether these agents improve the prognosis of elderly patients who have undergone autologous stem cell transplantation (auto-SCT). We retrospectively analyzed the outcome of 318 newly diagnosed patients aged 65–70 years who were treated between January 1, 2004, and December 31, 2009. As initial therapy, 192 patients were treated with conventional chemotherapy,88 with novel agent-containing regimens, 21 with conventional chemotherapy plus auto-SCT and the remaining 17 with novel agents plus auto-SCT. The median progression-free survival was 19.1, 24.5, 26.8 and 35.2 months, respectively, and the 5-year overall survival (OS) was 40, 62, 63 and 87%, respectively. Initial therapy with novel agents (p < 0.001) or auto-SCT (p < 0.02) significantly improved OS compared with the group without these treatment modalities. Salvage therapy with novel agents also significantly improved survival after relapse compared with conventional chemotherapy alone (p < 0.04). In a multivariate analysis, the use of novel agents was an independent prognostic factor significantly associated with extended OS(p < 0.003). These results indicate that novel agents and auto-SCT had a major impact on OS in eligible patients in this subgroup of MM.

Clinical significance of sIL-2R levels in B-cell lymphomas

Elevated soluble interleukin-2 receptor (sIL-2R) in sera is observed in patients with malignant lymphoma (ML). Therefore, sIL-2R is commonly used as a diagnostic and prognostic marker for ML, but the mechanisms responsible for the increase in sIL-2R levels in patients with B-cell lymphomas have not yet been elucidated. We first hypothesized that lymphoma cells expressing IL-2R and some proteinases such as matrix metalloproteinases (MMPs) in the tumor microenvironment can give rise to increased sIL-2R in sera. However, flow cytometric studies revealed that few lymphoma cells expressed IL-2R α chain (CD25) in diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL), and most CD25-expressing cells in the tumor were T-cells. Distinct correlations between CD25 expression on B-lymphoma cells and sIL-2R levels were not observed. We then confirmed that MMP-9 plays an important role in producing sIL-2R in functional studies. Immunohistochemical (IHC) analysis also revealed that MMP-9 is mainly derived from tumor-associated macrophages (TAMs). We therefore evaluated the number of CD68 and CD163 positive macrophages in the tumor microenvironment using IHC analysis. A positive correlation between the levels of sIL-2R in sera and the numbers of CD68 positive macrophages in the tumor microenvironment was confirmed in FL and extranodal DLBCL. These results may be useful in understanding the pathophysiology of B-cell lymphomas.

Usefulness of positron emission tomography in primary intestinal follicular lymphoma

Double-balloon enteroscopy (DBE) and video capsule endoscopy are useful for the diagnosis of lymphoma in the small intestine. However, DBE cannot be safely performed in cases with passage disturbance due to wall thickening and stenosis. Additionally, video capsule endoscopy cannot be performed in such cases because of the risk of retention. Here, we report 4 cases of primary follicular lymphoma of the gastrointestinal tract that could be detected using ¹⁸F-fluorodeoxyglucose positron emission tomography combined with computed tomography (PET-CT). The endoscopic findings of these 4 cases included lesions with wall thickening, which comprised macroscopically clusters of nodules, dense clusters of whitish granules or small nodules, fold thickening and ulcers with irregular margins that occupied the whole lumen with edematous mucosa. All patients fulfilled the World Health Organization grade 1 criteria. ¹⁸F-fluorodeoxyglucose PET-CT can help predict the risks that may result from certain endoscopic examinations, such as DBE and video capsule endoscopy.

Genomic vulnerability to LINE-1 hypomethylation is a potential determinant of the clinicogenetic features of multiple myeloma

BACKGROUND

The aim of this study was to clarify the role of global hypomethylation of repetitive elements in determining the genetic and clinical features of multiple myeloma (MM).

METHODS

We assessed global methylation levels using four repetitive elements (long interspersed nuclear element-1 (LINE-1), Alu Ya5, Alu Yb8, and Satellite-α) in clinical samples comprising 74 MM samples and 11 benign control samples (7 cases of monoclonal gammopathy of undetermined significance (MGUS) and 4 samples of normal plasma cells (NPC)). We also evaluated copy-number alterations using array-based comparative genomic hybridization, and performed methyl-CpG binding domain sequencing (MBD-seq).

RESULTS

Global levels of the repetitive-element methylation declined with the degree of malignancy of plasma cells (NPC>MGUS>MM), and there was a significant inverse correlation between the degree of genomic loss and the LINE-1 methylation levels. We identified 80 genomic loci as common breakpoints (CBPs) around commonly lost regions, which were significantly associated with increased LINE-1 densities. MBD-seq analysis revealed that average DNA-methylation levels at the CBP loci and relative methylation levels in regions with higher LINE-1 densities also declined during the development of MM. We confirmed that levels of methylation of the 5' untranslated region of respective LINE-1 loci correlated strongly with global LINE-1 methylation levels. Finally, there was a significant association between LINE-1 hypomethylation and poorer overall survival (hazard ratio 2.8, P = 0.015).

CONCLUSION

Global hypomethylation of LINE-1 is associated with the progression of and poorer prognosis for MM, possibly due to frequent copy-number loss.

Clinical features of gastrointestinal follicular lymphoma: comparison with nodal follicular lymphoma and gastrointestinal MALT lymphoma

We retrospectively compared the clinicopathological features of primary intestinal follicular lymphomas (FL-GIs), nodal follicular lymphomas (FL-LNs) and gastrointestinal MALT lymphomas (MALT-GIs), and investigated the distribution and the endoscopic appearances of FL-GI to evaluate the effectiveness of treatment modality. The subjects were 28 FL-GI patients, 135 FL-LN patients and 70 MALT-GI patients. In FL-LNs the clinical stage III-IV was 83%, while in FL-GIs clinical stage I-II was 68%. In MALT-GIs clinical stage I-II was 87%. The overall survival was significantly better in MALT-GI patients than in FL-LN patients. All FL-GI patients were alive at the time of evaluation. Regarding the histological grade (WHO), grade 1 was 81% in FL-GI, whereas in FL-LN grade 2 was 28% and grade 3 was 11%. The Follicular Lymphoma International Prognostic Index was low in 61% of FL-GIs, while in FL-LNs it was equally distributed to low, intermediate and high, suggesting that the prognosis is better in FL-GIs than in FL-LNs. The clinicopathological studies revealed the FL-GI has intermediate characteristics between FL-LN and MALT-GI. We recommend a 'watch-and-wait' policy or chemotherapy with rituximab for the therapy of FL-GIs because the lesions are often located in broader areas from the lower duodenum to the small intestine.

Phase II study of ABVd therapy for newly diagnosed clinical stage II-IV Hodgkin lymphoma: Japan Clinical Oncology Group study (JCOG 9305)

Although ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine) therapy has been regarded as a standard of care for advanced-stage Hodgkin lymphoma (HL) since 1992, there has been no prospective data of ABVD therapy in Japan. To investigate the efficacy and safety of ABVd therapy with the lower dose of dacarbazine (250 mg/m(2)) in patients with newly diagnosed stage II-IV HL, Lymphoma Study Group of Japan Clinical Oncology Group conducted a phase II study. The primary endpoints were complete response rate (%CR) and progression-free survival (PFS). A total of 128 patients with age less than 70 years were enrolled and received 6-8 cycles of ABVd followed by radiation to initial bulky mass. The %CR in 118 eligible patients was 81.4% [95% confidence interval (CI) 73.1-87.9%]. Major toxicity was grade 4 neutropenia (45.3%). Grade 3 nausea/vomiting was the most frequent non-hematological toxicity (10.9%). Transient grade 4 constipation, infection (abscess), hypoxemia and hyperbilirubinemia were observed in 4 patients. No treatment-related death was observed. PFS and overall survival at 5 years were 78.4% (95% CI 70.9-85.9%) and 91.3% (95% CI 86.1-96.5%), respectively. In conclusion, ABVd is effective in Japanese patients with stage II-IV HL with acceptable toxicities (UMIN-CTR Number: C000000092).

Central nervous system involvement in intravascular large B-cell lymphoma: a retrospective analysis of 109 patients

Intravascular large B-cell lymphoma (IVLBCL) is a rare disease entity with a high incidence of central nervous system (CNS) involvement at diagnosis. To evaluate CNS involvement, particularly recurrence including progression on therapy and relapse of IVLBCL, we retrospectively analyzed 109 patients with IVLBCL receiving chemotherapies with or without rituximab. In 82 patients (75%) without CNS involvement at initial diagnosis, risk of CNS recurrence at 3 years was 25% with a median follow-up in survivors of 39 months (range, 2-158 months). In 27 patients (25%) with CNS involvement at initial diagnosis, risk of CNS recurrence at 1 year was 25% with a median follow-up in survivors of 18 months (range, 10-77 months). Duration from diagnosis to CNS recurrence tended to be short in patients with CNS involvement at diagnosis. No significant difference in risk of CNS recurrence was found between patients receiving chemotherapies with or without rituximab. On multivariate analysis skin involvement at initial diagnosis was identified as a predictive factor for CNS recurrence in patients without CNS involvement at diagnosis (hazard ratio, 5.27; 95% confidence interval, 1.59-17.4; P = 0.007). Survival rate after CNS recurrence at 2 years was 12% in patients without CNS involvement at diagnosis. Central nervous system recurrence is a serious complication in IVLBCL patients and optimal strategies for CNS involvement should be established to obtain further improvements to clinical outcomes in the rituximab era.

Predictive value of endoscopy and endoscopic ultrasonography for regression of gastric diffuse large B-cell lymphomas after Helicobacter pylori eradication

BACKGROUND

Some gastric diffuse large B-cell lymphomas have been reported to regress completely after the successful eradication of Helicobacter pylori. The aim of this study was to investigate the clinical characteristics of gastric diffuse large B-cell lymphomas without any detectable mucosa-associated lymphoid tissue (MALT) lymphoma that went into complete remission after successful H. pylori eradication.

PATIENTS AND METHODS

We examined the effect of H. pylori eradication in 15 H. pylori-positive gastric diffuse large B-cell lymphoma patients without any evidence of an associated MALT lymphoma (clinical stage I by the Lugano classification) by endoscopic examination including biopsies, endoscopic ultrasonography, computed tomography, and bone marrow aspiration.

RESULTS

H. pylori eradication was successful in all the patients and complete remission was achieved in four patients whose clinical stage was I. By endoscopic examination, these gastric lesions appeared to be superficial. The depth by endoscopic ultrasonography was restricted to the mucosa in two patients and to the shallow portion of the submucosa in the other two patients. All four patients remained in complete remission for 7-100 months.

CONCLUSION

In gastric diffuse large B-cell lymphomas without a concomitant MALT lymphoma but associated with H. pylori infection, only superficial cases and lesions limited to the shallow portion of the submucosa regressed completely after successful H. pylori eradication. The endoscopic appearance and the rating of the depth of invasion by endosonography are both valuable for predicting the efficacy of H. pylori eradication in treating gastric diffuse large B-cell lymphomas.

Genomic screening for genes silenced by DNA methylation revealed an association between RASD1 inactivation and dexamethasone resistance in multiple myeloma

PURPOSE

Epigenetic changes such as DNA methylation play a key role in the development and progression of multiple myeloma. Our aim in the present study was to use genomic screening to identify genes targeted for epigenetic inactivation in multiple myeloma and assess their role in the development of resistance to dexamethasone.

EXPERIMENTAL DESIGN

Gene expression was examined using microarray screening, reverse transcription-PCR, and real-time quantitative PCR. DNA methylation was examined using bisulfite PCR, bisulfite sequencing, and bisulfite pyrosequencing in 14 multiple myeloma cell lines, 87 multiple myeloma specimens, and 12 control bone marrow samples. WST-8 assays were used to assess cell viability after treatment with 5-aza-2'-deoxycytidine and/or dexamethasone.

RESULTS

Microarray analysis was done to screen for genes up-regulated by 5-aza-2'-deoxycytidine. In RPMI8226 cells, 128 genes were up-regulated, whereas 83 genes were up-regulated in KMS12PE cells. Methylation of 22 genes with CpG islands in their 5' regions, including RASD1, was confirmed. Methylation of RASD1 was associated with its inactivation, which correlated with resistance to dexamethasone. Treating multiple myeloma cells with 5-aza-2'-deoxycytidine restored sensitivity to dexamethasone. Methylation of RASD1 was also detected in a subset of primary multiple myeloma specimens, and the levels of methylation were increased after repeated antitumor treatments. Gene signature analysis revealed various genes to be synergistically induced by treatment with a combination of 5-aza-2'-deoxycytidine plus dexamethasone.

CONCLUSION

Our findings indicate that epigenetic inactivation of genes, including RASD1, plays a key role in the development of dexamethasone resistance in multiple myeloma. Moreover, they show the utility of demethylation therapy in cases of advanced multiple myeloma.

Serum soluble interleukin-2 receptor level and immunophenotype are prognostic factors for patients with diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma is the most common form of non-Hodgkin lymphoma. Although many studies have attempted to identify prognostic factors, most have focused on conventionally treated patients. The influence of anti-CD20 antibody (rituximab) should be considered now. We evaluated the prognostic significance of serum soluble interleukin-2 receptor levels and germinal center B-cell-like or non-germinal center B-cell like subgroups in 80 patients with diffuse large B-cell lymphoma, who had been treated with rituximab. Serum soluble interleukin-2 receptor levels ranged from 322 to 39900 U/mL (median 1365 U/mL). Sixteen (20%) were germinal center B-cell-like subgroups, and the remainder (80%) non-germinal center B-cell-like. Survival analysis associated lower serum soluble interleukin-2 receptor level and germinal center B-cell-like phenotype with better overall survival (P = 0.015), whereas multivariate analysis, including International Prognostic Index factors, revealed that only higher performance status score and higher serum lactate dehydrogenase levels significantly affected survival. However, serum soluble interleukin-2 receptor levels were elevated in patients with higher International Prognostic Index scores as well as in the non-germinal center B-cell-like subgroup. Serum soluble interleukin-2 receptor levels, International Prognostic Index, and subphenotypes were strongly correlated with each other. Our study showed that soluble interleukin-2 receptor is quite useful and may serve as a substitute for the International Prognostic Index, especially for patients undergoing treatment. Moreover, the differentiation between the germinal center B-cell-like and non-germinal center B-cell-like phenotypes is also useful for predicting patients with diffuse large B-cell lymphoma, even among those treated with rituximab.

IL-6-induced activation of MYC is responsible for the down-regulation of CD33 expression in CD33+ myeloma cells

Human myeloma cells from about 10% of cases with multiple myeloma expressed CD33 and had monocytoid morphology with convoluted nuclei, and all these patients had no increase in serum CRP values. In CD33(+) myeloma cells as well as myeloma cell lines, CD33 expression levels were correlated with the increased expression levels of CEBPA (C/EBPalpha). This correlation was confirmed by the finding that transfection with the CEBPA gene induced CD33 expression in a CD33(-) myeloma cell line. As suggested by the lack of an increase in serum CRP values in CD33(+) myelomas, IL-6 down-regulated the expression of CD33 in CD33(+) myeloma cell lines along with the down-regulation of CEBPA gene expression. Cucurbitacin I (STAT3 inhibitor), but not U0126 (MAPK inhibitor), could abolish the effect of IL-6. Furthermore, IL-6 up-regulated the expression of MYC via STAT3 phosphorylation and MYC bound to the promoter region of the CEBPA gene followed by the down-regulation of CEBPA expression. It was confirmed that introduction of shRNA for MYC into a CD33(+) myeloma cell line blocked the IL-6-induced down-regulation of CD33 and CEBPA expression. Therefore, these results indicate that IL-6 can reverse the expression level of CD33 by up-regulating MYC followed by the down-regulation of CEBPA expression.

Ectopic cyclin D1 overexpression increases chemosensitivity but not cell proliferation in multiple myeloma

We established a myeloma cell line (RPMI8226) with cyclin D1 overexpression in which the transfected cyclin D1 gene was stably expressed. D1 transfectants showed down-regulation of cyclin D2. Cell proliferation analysis did not show any differences among RPMI8226, mock control, and D1 transfectants. The number of S-phase cells increased while the number of G0/G1- and G2/M-phase cells decreased in D1 transfectants, which indicates a prolonged S-phase caused by cyclin D1 transfection. A decreased number of G2/M-phase cells was also detected in myeloma cells of patients with translocation t(11;14)(q13;q32). Western blot analysis revealed an increase in the hyperphosphorylated form of retinoblastoma (Rb) protein in D1 transfectants; however, the expression of p53, p16, Bax, Bad, Bcl-2, and Mcl-1 did not significantly change. Treatment with anti-myeloma drugs (melphalan, dexamethasone, bortezomib and immunomodulatory compounds) induced apoptosis earlier in D1 transfectants compared with RPMI8226 and mock control via the activation of both caspase-8 and -9. However, we could not detect a relationship between cyclin D1 expression and the response to treatment with VAD and bortezomib. Therefore, we assume that high sensitivity to anti-myeloma drugs depends on the duration of the S-phase, but a clinical response might depend on the number of myeloma cells with cyclin D1 overexpression.

Retrospective Analysis of Intravascular Large B-Cell Lymphoma Treated With Rituximab-Containing Chemotherapy As Reported by the IVL Study Group in Japan

Purpose

To evaluate the safety and efficacy of rituximab-containing chemotherapies for intravascular large B-cell lymphoma (IVLBCL).

Patients and Methods

We retrospectively analyzed 106 patients (59 men, 47 women) with IVLBCL who received chemotherapy either with rituximab (R-chemotherapy, n = 49) or without rituximab (chemotherapy, n = 57) between 1994 and 2007 in Japan. The median patient age was 67 years (range, 34 to 84 years). The International Prognostic Index was high-intermediate/high in 97% of patients.

Results

The complete response rate was higher for patients in the R-chemotherapy group (82%) than for those in the chemotherapy group (51%; P = .001). The median duration of follow-up for surviving patients was 18 months (range, 1 to 95 months). Progression-free survival (PFS) and overall survival (OS) rates at 2 years after diagnosis were significantly higher for patients in the R-chemotherapy group (PFS, 56%; OS, 66%) than for patients in the chemotherapy group (PFS, 27% with P = .001; OS, 46% with P = 0.01). Multivariate analysis revealed that the use of rituximab was favorably associated with PFS (hazard ratio [HR], 0.45; 95% CI, 0.25 to 0.80; P = .006) and OS (HR, 0.42; 95% CI, 0.21 to 0.85; P = .016). Treatment-related death was observed in three patients (6%) who received R-chemotherapy and in five patients (9%) who received chemotherapy.

Conclusion

Our data suggest improved clinical outcomes for patients with IVLBCL in the rituximab era. Future prospective studies of rituximab-containing chemotherapies are warranted.

Osteoprogenitor differentiation is not affected by immunomodulatory thalidomide analogs but is promoted by low bortezomib concentration, while both agents suppress osteoclast differentiation

We investigated the effects of bortezomib (PS-341) and immunomodulatory thalidomide analogs (immunomodulatory compounds; CC-4047, CC-6032, and CC-5013, or lenalidomide) on osteoblast and osteoclast differentiation in vitro using human mesenchymal stem cells (hMSC) to commit to osteoprogenitor cells and peripheral blood mononuclear cells (PBMCs) isolated from healthy donors, respectively. First, the concentration of bortezomib for an anti-myeloma effect was more than 1.0 nM in myeloma cells of multiple myeloma (MM) patients and more than 2.5 nM in myeloma cell lines. In contrast, anti-myeloma effects of immunomodulatory compounds on myeloma cells differed among myeloma cells and these compounds themselves. Subsequently, these agents (bortezomib; 0.5-5.0 nM, immunomodulatory compounds; 10 microM) were added to the osteoprogenitor cell culture media or the media for osteoclast differentiation. Low bortezomib concentrations (0.5 and 1.0 nM) increased ALP activity, and the delayed addition of bortezomib further increased ALP activity. Mineralized nodular formation with <2.5 nM bortezomib was not impaired. BMP2 expression on osteoprogenitor cells was found to increase in a time-dependent manner irrespective of treatment with bortezomib. On the other hand, the anti-osteoclast effect with low bortezomib concentration (< or =2.5 nM) depended on MM patients. In contrast, immunomodulatory compounds at 10 microM showed an anti-osteoclast effect without cytotoxicity to osteoblast differentiation, at which dose myeloma cells underwent apoptosis. These findings might improve the treatment strategy for MM patients without damaging BM stromal cells by combining bortezomib with immunomodulatory compounds.

[Biochemical and immunological findings of multiple myeloma]

Biochemical and immunological findings of multiple myeloma are reviewed. Rate of abnormal data of biochemical markers in monoclonal gammopathy of undetermined significance (MGUS), asymptomatic myeloma and symptomatic myeloma are reported. Serum albumin, beta2-microglobulin, lactate dehydrogenase, C-reactive protein, serum calcium and creatinine are prognostic factors. Free light chain (FLC) assay is useful for monitoring of intact immunoglobulin myeloma as well as nonsecretory and light chain only myeloma. In MGUS, serum FLC ratio is an independent risk factor for progression. Phenotypic analysis of plasma cells is useful for differential diagnosis and understanding of proliferative state in multiple myeloma.

Connective tissue growth factor is an indicator of bone involvement in multiple myeloma, but matrix metalloproteinase-9 is not

Bone disease (BD) in multiple myeloma (MM) is because of the activation of osteoclasts and impairment of osteoblast differentiation. Connective tissue growth factor (CTGF) is known to participate in the differentiation of mesenchymal stem cells to committed osteoprogenitor cells. We analysed the concentration of circulating CTGF in 35 MM patients and 22 malignant lymphoma (ML) patients and 14 normal individuals. CTGF is protease-sensitive and thus is found as both an N-terminal half fragment (N-half CTGF) and whole (W-CTGF). Serum levels of W-CTGF and N-half CTGF + W-CTGF were determined by separate sandwich enzyme-linked immunosorbent assays. The level of W-CTGF was significantly lower (P < 0.005) in MM patients compared with ML patients and normal individuals, while N-half + W-CTGF was similar in all groups. Furthermore, W-CTGF was significantly lower in MM patients with BD compared with those without BD (P < 0.005) and this was independent of previous treatment. Matrix metalloproteinase (MMP)-9 is produced by myeloma cells and is thought to be related to BD in MM. However, MMP-9 does not cleave CTGF and serum MMP-9 level was not related to BD in MM. Thus, CTGF is an indicator of BD in MM; its metabolism and function in MM should be clarified.

Induction of multilineage markers in human myeloma cells and their down-regulation by interleukin 6

Human primary myeloma cells are well known to be heterogeneous with regard to morphology and surface phenotype. We confirmed the heterogeneous expression of such multilineage markers as CD33, CD7, CD56, CD4, and CD86 in primary myeloma cells from 20 patients with multiple myeloma and in 8 human myeloma cell lines. CD33 expression in the Liu01 cell line, a subclone of U266 cells, and in vitamin D3-treated ILKM3 cells, correlated with a monocytoid morphology featuring convoluted nuclei and with increased C/EBPalpha expression. CD56+ myeloma cells from some myeloma patients and the CD56+ (but not the CD56-) myeloma cell lines expressed neuronal cell markers, such as neuron-specific enolase and beta-tubulin III. CD7 expression in Liu01 cells and forskolin-stimulated U266 cells coincided with the presence of large cytoplasmic granules, and these cells featured increased expression of perforin messenger RNA and significant natural killer cell activity. Interleukin 6 (IL-6), a growth factor for myeloma cells, down-regulated CD33, CD7, or CD56 expression in primary myeloma cells, as well as in Liu01 cells. Therefore, these data suggest that human myeloma cells are capable of inducing the expression of multilineage markers and that IL-6 can down-regulate such expression.

The pharmacokinetics of low-dose thalidomide in Japanese patients with refractory multiple myeloma

Thalidomide has been used for the treatment of refractory multiple myeloma, the dosage in Japan is lower than in other countries; however, there is little information on the pharmacokinetics and their relationship with the drug response. The aim of this study was to characterize the pharmacokinetics of low-dose thalidomide in Japanese patients with refractory multiple myeloma, and to examine the relationship between pharmacokinetics and adverse events. On the first and second days, a 100 mg capsule was administered to 8 Japanese patients after breakfast and blood samples were obtained. The plasma concentrations were measured using HPLC and analyzed based on a one-compartment model. If intolerable adverse events were not observed for 14 d, the dose was increased to 200 mg. The average apparent volume of distribution (Vd/F), apparent total clearance (CL/F) and area under the plasma concentration-time curve from 0 to infinity (AUC0-infinity), which were 45.3 l, 5.5 l/h and 21.7 microg.h/ml, respectively, with smaller Vd/F and CL/F and larger AUC0-infinity than in Caucasian populations. This pharmacokinetic difference may explain the dose difference between Japan and other countries. Adverse events were associated with AUC0-infinity, which was best correlated with plasma concentration at 12 h after administration. The 12-h time point was suggested to be a capable indicator for "safety-oriented" therapeutic drug monitoring of thalidomide.

[A case of systemic amyloidosis treated by chemotherapy with autologous peripheral blood stem cell transplantation]

A 67-year-old woman was admitted to our hospital because of breathlessness. Systemic amyloidosis had been diagnosed 5 years previously. Her chest X-ray film showed multiple nodules in both lung fields. Chest computed tomography (CT) revealed some of the nodules had calcifications. Bronchoscopy demonstrated amyloid deposits in the bronchial walls. The serum titer of anti-SS-A antibody was high. Results of both the Schirmer Test and the Rose-Bengal Test were positive. The final diagnosis was systemic amyloidosis with Sjögren's syndrome. She was treated by chemotherapy using high dose melphalan with autologous peripheral blood stem cell transplantation (PBSCT). It was obvious that her chest X-ray film findings and bronchoscopic findings had improved 9 months after high dose chemotherapy with PBSCT. The disappearance of M protein and improvement of thirst, a symptom of Sjögren's syndrome, were also observed.

Heterogeneous expression of CD32 and CD32-mediated growth suppression in human myeloma cells

BACKGROUND AND OBJECTIVES

An increased level of serum M-protein IgG may affect the growth or survival of myeloma cells through the Fcgamma inverted exclamation mark receptor (FcgammaR) in human myelomas. We examined the expression of FcgammaR (CD32, CD16 and CD64) and compared the effect of anti-CD32 antibody on the viability of myeloma cells to that on the viability of normal plasma cells.

DESIGN AND METHODS

Surface antigen and gene expressions were examined by flow cytometry and reverse transcription polymerase chain reaction, respectively. We examined the effect of anti-CD32 antibody on the viability of CD19- myeloma cells (including immature and mature myeloma cells) and CD19+ normal plasma cells. In order to confirm the involvement of CD19 in the anti-CD32-mediated growth suppression, we used CD19 transfectants of myeloma, B-cell and erythroleukemia cell lines that we have already established.

RESULTS

CD32 was significantly expressed on primary myeloma cells, but immature, MPC-1- myeloma cells expressed CD32 more weakly than mature, MPC-1+ cells. Treatment with anti-CD32 antibody decreased the viability of normal plasma cells (CD38++ CD19+) more than that of myeloma cells (CD38++ CD19-); CD32-mediated growth suppression was greater in mature MPC-1+ cells than in immature MPC-1- cells. The introduction of CD19 into CD19- cell lines significantly increased the sensitivity of the cells to treatment with anti-CD32 antibody as well as addition of IgG complex; furthermore, increased phosphorylation of CD32 and SHIP was detected in CD19-transfected cell lines.

INTERPRETATION AND CONCLUSIONS

Myeloma cells lacking CD19 expression are less sensitive to CD32-mediated growth suppression than are CD19+ normal plasma cells.

An increase in MPC-1- and MPC-1-CD45+ immature myeloma cells in the progressive states of bone marrow plasmacytosis: the revised phenotypic classification of monoclonal marrow plasmacytosis (MOMP-2005)

The heterogeneity of bone marrow plasmacytosis is clearly analyzed by multicolor staining with anti-CD38 antibody. To date, at least 5 subpopulations of plasma cells have been identified in the bone marrow of multiple myeloma (MM) patients with regard to the expression of MPC-1, CD49e (VLA-5), and CD45: MPC-1(-)CD49e(-)CD45(+) proliferative immature cells, MPC-1(-)CD49e(-)CD45(-) immature myeloma cells, MPC-1(+)CD49e(-)CD45(-) and MPC-1(+)CD49e(-)CD45(+) intermediate myeloma cells, and MPC-1(+)CD49e(+)CD45(+) mature myeloma cells. We performed phenotypic analyses in 75 cases of monoclonal bone marrow plasmacytosis, including 46 cases of MM and 29 cases of monoclonal gammopathy of undetermined significance (MGUS). In 31 cases of progressive MM disease, MPC-1(-) immature and MPC-1(-)CD45(+) proliferative immature myeloma cells were significantly increased up to >25% and >10%, respectively, of the plasma cell fractions (CD38(++) cells), whereas there were no increases in MPC-1(-) or MPC-1(-)CD45(+) proliferative immature myeloma cells in 15 cases of stable disease. Interestingly, the proportions of MPC-1(-) and MPC-1(-)CD45(+) immature monoclonal plasma cells also increased in the 7 progressive cases of MGUS. Finally, we present the revised (2005) phenotypic classification of monoclonal marrow plasmacytosis (MOMP-2005).

Humanized anti-interleukin-6 receptor antibody treatment of multicentric Castleman disease

Multicentric Castleman disease (MCD) is an atypical lymphoproliferative disorder characterized by systemic lymphadenopathy and constitutional inflammatory symptoms. Dysregulated overproduction of interleukin-6 is responsible for the clinical abnormalities. This multicenter prospective study was undertaken to evaluate the safety and efficacy of a humanized anti-human interleukin-6 (IL-6) receptor monoclonal antibody (MRA) in patients with MCD. We report here results of the first 60 weeks of the study enrolling 28 patients. The initial dosing period consisted of 8 infusions of 8 mg/kg MRA administered biweekly. Adjustments in the dose and treatment interval were allowed for each patient in an extension phase after 16 weeks. Within 16 weeks, treatment with MRA consistently alleviated lymphadenopathy and all the inflammatory parameters. Hemoglobin, albumin, and total cholesterol levels, high-density lipoprotein cholesterol values, and body mass index all increased significantly. In addition, fatigue diminished. Chronic inflammatory symptoms were successfully managed over 60 weeks. In 8 (28.6%) patients, the MRA dose was decreased or the treatment interval was extended without exacerbation. Eleven (73.3%) of 15 patients who had received oral corticosteroids before study entry were able to do well on a reduced corticosteroid dose. Most adverse events were mild to moderate in severity. MRA was tolerated well and significantly alleviated chronic inflammatory symptoms and wasting in patients with MCD.

Reduced-Intensity Conditioning Allogeneic Stem Cell Transplantation for Multiple Myeloma: Results from the Japan Myeloma Study Group

We conducted a retrospective survey of multiple myeloma (MM) patients who underwent reduced-intensity conditioning allogeneic stem cell transplantation (RIST) at 11 hospitals participating in the Japan Myeloma Study Group. Forty-five patients (median age, 53 years) were included in this study. The conditioning regimen consisted of a fludarabine-based regimen in 24 patients and a regimen based on total body irradiation (1-2 Gy) in 18 patients. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and tacrolimus in 28 and 17 patients, respectively. All patients showed myeloid engraftment. Complete chimerism was obtained in 42 patients. Grade II to IV acute GVHD developed in 28 (65%) of 43 patients evaluated, and chronic GVHD developed in 31 (76%) of 41 patients. Early death before day 100 was observed in 4 patients (8.8%). A complete response (CR) was obtained in 12 patients. The factors affecting overall survival were severe acute GVHD and the response after RIST. To date, 18 patients are alive, with 9 patients remaining in CR at a median follow-up of 25 months. The overall and progression-free survival rates at 3 years were 38.5% and 18.8%, respectively. These observations suggest that RIST is feasible with reliable donor engraftment and relatively low transplantation-related mortality in Japanese MM patients.

Dehydroepiandrosterone can inhibit the proliferation of myeloma cells and the interleukin-6 production of bone marrow mononuclear cells from patients with myeloma

The serum levels of an adrenal sex hormone, dehydroepiandrosterone sulfate (DHEA-S), are significantly more decreased in human myelomas compared with the reduction brought by physiologic decline with age. In order to clarify the effect of DHEA on myeloma cells, we investigated whether DHEA and DHEA-S could inhibit interleukin-6 (IL-6) production of bone marrow mononuclear cells and the proliferation of myeloma cells from patients with myeloma. DHEA-S and DHEA suppressed IL-6 production from a bone marrow stromal cell line, KM-102, as well as in bone marrow mononuclear cells from patients with myeloma. Furthermore, DHEA inhibited in vitro growth of the U-266 cell line and primary myeloma cells from the patients, as well as the in vivo growth of U-266 cells implanted i.p. in severe combined immunodeficiency-hIL6 transgenic mice. DHEA up-regulated the expression of peroxisome proliferator-activated receptor (PPAR), PPAR beta, but not PPARgamma or PPARalpha, and the expression of IkappaBalpha gene in myeloma cells and bone marrow stromal cells, which could explain the suppressive effect of DHEA on IL-6 production through the down-regulation of NF-kappaB activity. Therefore, these data revealed that DHEA-S, as well as DHEA, had a direct effect on myeloma and bone marrow stromal cells to inhibit their proliferation and IL-6 production, respectively.