Low Beta2-microglobulin Levels Research Articles

Tumor beta2-microglobulin and HLA-A expression is increased by immunotherapy and can predict response to CIT in association with other biomarkers.

Downregulation of MHC class I expression and/or defects in the antigen presentation pathways are commonly reported in human cancers. Numerous studies previously have explored extensively the molecular mechanisms that underlie HLA-class I and Beta2-Microglobulin (B2M) downregulation. However, the techniques presently available to detect expression of MHC class I proteins lack the robustness, specificity and sensitivity needed for systematic integration and analysis in clinical trials. Furthermore, the dynamics of HLA-class I and B2M expression have not been comprehensively studied as a potential biomarker for immunotherapy. Using novel, validated, immunohistochemistry (IHC)-based methods for quantifying B2M and HLA-A in tumor samples from diverse cancer types, we have determined loss of B2M and HLA-A proteins in 336 archived, primary specimens and 329 biopsies from metastatic patients collected during Roche-sponsored Phase 1 clinical trials investigating novel immunotherapy candidates as monotherapy or in combination with CPI. Up to 56% of cases with B2M or HLA-A loss were noted in the investigated tumor types. The frequency of loss was dependent on indication and stage of disease and revealed heterogeneous expression patterns across patients. B2M and HLA-A loss was increased in metastatic lesions compared to primary tumors, indicating selection of MHC class I low clones in metastatic and refractory tumor cells. High on-treatment B2M expression correlated with successful clinical outcome (RECIST), while high baseline B2M did not. A treatment-induced increase of B2M expression was noted in most of the patients with low B2M levels at baseline. The triple biomarker combination of B2M, CD8 and PDL1 strongly improved response prediction to cancer immunotherapy. Our results indicate that B2M and HLA-A loss occurs frequently in tumors and is reversed in most instances following immunotherapy which supports the conclusion that MHC class I loss is not the dominant resistance mechanism to CPI treatment. This investigation reveals a highly dynamic expression of HLA-A and B2M in tumors affected by indication, metastatic status, immunophenotype and immunotherapy treatment. Baseline expression levels of B2M on tumors may be of utility as a constituent of a biomarker panel used for selecting patients for immunotherapy clinical trials.

Single-Center Real-World Experience with Primary Central Nervous System Lymphoma in the 21st Century

Background/Aims: In Korea, the incidence of primary diffuse large B-cell lymphoma of the central nervous system (PCNSL) is increasing and autologous stem cell transplantation (ASCT) has improved the survival of younger patients. We explored our real-world experience with PCNSL at Asan Medical Center (AMC).Methods: We used the AMC lymphoma registry to collect patient data prospectively. We analyzed 279 patients diagnosed from 2002 until August 2019.Results: The PCNSL incidence at AMC increased progressively and comprised 7.4-8.9% of new non-Hodgkin lymphoma patients annually during the most recent 4 years. The median age was 60 years (range, 17-85) and males comprised 55%. Patients under 65 years of age (n = 183) had no significant differences in characteristics compared to those aged 65 years or over, with the exception of less occipital lobe involvement and lower beta-2 microglobulin levels. Rituximab, methotrexate, procarbazine, and vincristine (R-MPV) combination induction had the best overall response, of 95%. The median overall survival was 3.8 years with 5- and 10-year survival rates of 41.5% and 30.2%, respectively. Survival was better in younger patients and those treated with ASCT. Thiotepa, busulfan, and cytoxan (TBC) conditioning chemotherapy had better survival than other combinations. The International Extranodal Lymphoma Study Group and Memorial Sloan Kettering Cancer Center prognostic score systems were valid in this cohort. Age and performance status were independent prognostic factors. Exclusive extra-central nervous system failure occurred in six patients (5.6%) among 107 failures.Conclusions: The incidence of PCNSL is rising. R-MPV induction therapy followed by ASCT with TBC has improved the survival of young, fit PCNSL patients.

Lower serum beta-2 microglobulin levels are associated with worse survival in incident peritoneal dialysis patients.

There is a general consensus that elevated serum beta-2 microglobulin (B2M) levels measured at a single time-point are significantly associated with mortality in patients on maintenance dialysis. To date, the majority of prior studies that have examined B2M-associated mortality have been conducted in prevalent hemodialysis patients with little residual renal function (RRF). However, studies in incident peritoneal dialysis (PD) patients are lacking. Moreover, changes in serum B2M levels over time have not been considered in this population. We examined the association of time-updated and baseline serum B2M levels with mortality in a 10-year cohort of 725 incident PD patients who were maintained on dialysis between January 2006 and December 2011 using Cox proportional hazards regression analyses. Patients were categorized into tertiles according to B2M levels. During a median follow-up of 38 (interquartile range 23-64) months, 258 (35.4%) deaths occurred, including 106 (14.6%) and 86 (11.9%) deaths from cardiovascular and infectious causes, respectively. The lowest B2M tertile was associated with a higher risk of all-cause and infectious mortality compared with the middle tertile: the hazard ratios (95% confidence interval) for all-cause deaths were 2.12 (1.38-3.26) and 2.20 (0.96-5.05) in time-varying analyses and 1.52 (1.07-2.17) and 2.41 (1.19-4.88) in baseline analyses. Subgroup analyses showed that this association was particularly observed in females, older patients, those with comorbidities such as diabetes, a lower body mass index, lower albumin levels or those with higher RRF (all P for interactions <0.05). In incident PD patients, lower B2M levels were independently associated with overall and infectious mortality. These associations can be potentially modified by malnutrition, inflammation and RRF.

Clinical Relevance of Circulating Poly-Ubiquitin as a Prognostic Indicator in Chronic Lymphocytic Leukemia.

Abstract 1240Poster Board I-262The ubiquitin-proteasome pathway is implicated in the pathogenesis of many hematological malignancies. We have reported that proteasome activities in plasma samples can be detected in patients with chronic lymphocytic leukaemia (CLL). Here we examined the correlation of plasma ubiquitin protein levels with clinical behavior in CLL patients. Using the Meso Scale Discovery (MSD) platform, we quantified poly-ubiquitin levels in plasma samples from 138 patients with CLL and 101 healthy control subjects, and examined the associations of ubiquitin levels with various clinical and laboratory variables and overall survival. Patients with CLL had significantly higher levels of poly-ubiquitin proteins (median=158.2; range=35.0-281.2) than did normal control subjects (median=57.3; range=22.0-160.2) (P<0.001). Poly-ubiquitin levels showed no correlation with Rai stage, performance status, beta-2 microglobulin (B2M), or the mutation status of IgVH. However, when considered as a continuous variable, poly-ubiquitin levels correlated negatively with survival. Higher levels of poly-ubiquitin were associated with longer survival (P=0.04). In a multivariate model incorporating poly-ubiquitin, B2M, and IgVH mutation status only B2M (P=0.00004) and poly-ubiquitin P=0.04) levels, but not IgVH mutation status (P=0.12), were independent predictors of survival. When a cut- point corresponding to the upper quartile was used, patients with poly-ubiquitin levels >193 ng/mL had significantly better survival than did those with lower levels. Using B2M and poly-ubiquitin in combination allowed us to stratify patients into 3 different groups : survival was greatest in patients with high poly-ubiquitin and low B2M levels, lowest in those with low poly-ubiquitin and high B2M levels, and intermediate in those with high levels of B2M and ubiquitin or low levels of both (P<0.00001). In conclusion, these findings confirm the importance of the proteasome-ubiquitin system in the pathophysiology of CLL. Moreover, our data also suggest that plasma levels of poly-ubiquitin, along with B2M, should be explored as a prognostic factor in CLL. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Predictive factors for survival in myeloma patients who undergo autologous stem cell transplantation: a single-centre experience in 211 patients

High-dose therapy with autologous stem cell therapy (ASCT) has become the treatment of choice for eligible patients with myeloma. We analysed retrospectively the prognostic influence of pre-transplant characteristics and transplant modalities on response and survival in 211 myeloma patients who were transplanted in our centre between 1994 and 2004. All patients received peripheral blood stem cell support after conditioning with melphalan alone (183 patients), or melphalan and total blood irradiation (28 patients). We evaluated the influence of age, type of multiple myeloma, status prior and post ASCT, previous treatment regimens, time of ASCT from diagnosis, year of autograft, dose of re-infused CD34(+) cells, plasma cell infiltration and beta2-microglobulin at diagnosis on overall survival (OS) and event-free survival (EFS) to define patients with better prognosis. Median OS and EFS from transplantation were 50.9 and 20.1 months, respectively. Median OS from diagnosis was 68.8 months. Transplant-related mortality was 1.4%. Lower beta2-microglobulin levels, achievement of complete remission (CR) post transplant and lower plasma cell infiltration at diagnosis and transplant correlated with longer EFS and OS, whereas CR at transplant and low international prognostic index at transplant correlated with better EFS. Higher CD34(+) cell dose correlated with improved OS. We conclude that ASCT is safe and effective and the outcome is independent of age, time from diagnosis, previous treatment and conditioning regimen.

Management of musculoskeletal complications in endstage renal disease: an update

People treated with prolonged hemodialysis now survive longer and increasingly develop musculoskeletal complications. Significant advances have been made in the management of musculoskeletal manifestations in patients undergoing hemodialysis for endstage renal disease. Noncalcium-based phosphate binders are preferred for the management of hyperphosphatemia. Vitamin D therapy is based on intact parathyroid hormone levels. Newer Vitamin D sterols and calcimimetic agents seem to control secondary hyperparathyroidism without increasing the calcium-phosphorous product. Use of biocompatible dialyzers for hemodialysis may delay articular manifestations of beta-2 microglobulin amyloidosis. Beta-2 microglobulin adsorption columns when used along with hemodialysis may lead to lower beta-2 microglobulin levels and improvement in articular manifestations of beta-2 microglobulin amyloidosis. In this review, we focus on the latest advancements in the management of secondary hyperparathyroidism and beta-2 microglobulin amyloidosis.

Waldenström's macroglobulinemia.

Waldenström's macroglobulinemia (WM) is a clinical syndrome with diverse prognoses, and not all patients require therapy at diagnosis. Serum beta2 microglobulin is a major prognostic determinant, and asymptomatic patients with low beta2 microglobulin levels and preserved hemoglobin can be observed over long periods without therapy. Low-dose alkylating agents and purine analogs are commonly employed as initial therapy but rarely yield complete remissions. Patients who are refractory to or have relapse after alkylator or purine analogue therapy can be salvaged with purine analogs. Improvement in outcome demands a comprehensive approach aimed at increasing and sustaining complete remissions. Such an approach should probably employ Rituxan (IDEX Pharmaceuticals, La Jolla, CA) in conjunction with induction therapy, peripheral stem cell procurement before purine analog therapy, and high-dose therapy followed by maintenance therapy with interferon.

Clinical Features and Outcome of Multiple Myeloma Arising from the Transformation of a Monoclonal Gammapathy of Undertermined Significance

Patients with a monoclonal gammapathy of undertermined significance (MGUS) are usually submitted to a periodical clinical follow-up, but it is not known if this surveillance can ameliorate the prognosis of a plasma cell malignancy that will be eventually detected. We compared the clinical and laboratory characteristics at onset, the response to chemotherapy and the survival, of 21 cases of newly diagnosed multiple myeloma (MM) arising from the malignant transformation of MGUS and 41 cases without a previous history of MGUS, recruited to the same first-line treatments over a 3-ears period. The former group showed a significant lower frequency of advanced stages as well as other several prognostic factors of high risk including anemia, renal failure, bone lesions and increase of beta2 microglobulin and C-reac-tive protein levels. Despite a similar response to treatment of the two groups, MM arising from MGUS showed a significantly longer median survival than MM without prior MGUS. This was particularly true for stage I, while stages II and III behaved similarly. We conclude that the regular clinical monitoring of MGUS patients allowed the identification of earlier malignant transformation, when tumor burden is lower, as indicated by lower beta2 microglobulin levels and marrow plasmacytosis of stage I MM arising from MGUS. Moreover, a slower proliferation rate of myeloma cells, as suggested by lower C-reactive protein levels, may be considered so as to explain the longer survival of these patients.

Characterization of Myeloma Cells by Means of Labeling Index, Bone Marrow Histology, and Serumβ2-Microglobulin

The relationship between two cellular prognostic parameters of multiple myeloma, the plasma cell labeling index (LI%) and bone marrow histology was studied. The LI% as the percentage of monoclonal plasma cells in the S-phase was measured by bromodeoxyuridine incorporation using the anti-bromodeoxyuridine antibody BU-1. The histologic classification was based on six plasma cell types that allow prognostic grading as the Marschalko, small cell, cleaved, polymorphous, asynchronous, and blastic types. The biopsies also were used for estimating the degree of infiltration. Beta 2-microglobulin (IMx assay, Abbott, North Chicago, IL), the most significant serum parameter for myeloma also was measured for comparison. Bone marrow specimens and sera were obtained from 50 myeloma patients. Fourteen patients with smoldering myeloma were characterized by well-differentiated Marschalko or small cell type cells, a low LI% and a low beta 2-microglobulin concentration. Considering all myeloma patients, plasma cell type and degree of infiltration showed a significant correlation with LI% and beta 2-microglobulin concentration. Patients with plasma cells that were not mature cells of the Marschalko or small cell type revealed a high LI% or high beta 2-microglobulin level in 16 of 19 cases. However, a high LI% or high beta 2-microglobulin level could be detected in only 8 of 31 patients with plasma cells of the Marschalko or small cell type. Three of 21 stage I patients did not show the typical finding of a low LI%, low beta 2-microglobulin level, and a favorable grade. Stage II patients were not uniformly characterized by LI%, beta 2-microglobulin and plasma cell morphology. The percentage of nucleolated plasma cells was not associated with the LI%. Bone marrow histology, LI%, and beta 2-microglobulin concentration appear to be supplementary prognostic factors. If LI% and beta 2-microglobulin levels are not measured, a higher risk could be overlooked in cases with mature plasma cells.

6The role of haematopoietic stem cell-supported myeloablative therapy for the management of multiple myeloma

Haematopoietic stem cell-supported myeloablative therapy appears to be a promising treatment modality for MM. It yields increased overall response and CR rates when compared with conventional chemotherapy, and seems to prolong the duration of survival. These conclusions, while encouraging, have mostly been drawn from uncontrolled studies carried out in select groups of patients and, obviously, need to be confirmed in controlled clinical trials. While the results of these studies are still awaited, the wider application of BMT should probably be encouraged. As in other malignancies, the best candidates appear to be those less heavily pre-treated, with chemosensitive disease, low tumour cell mass and other favourable prognostic features, for example low beta 2-microglobulin levels. Under these conditions, the chance of entering CR following BMT, be it autologous or allogeneic, is currently estimated to be of at least 50%, and the long-term probability of survival averages approximately 30%. However, while it appears that a plateau for progression-free survival cannot be ascertained following a single ABMT, reported observations of patients with continued disease-free survivals up to and beyond 10 years after allografting suggest that this latter procedure may be curative. It seems likely therefore that the higher mortality related to allogeneic BMT (which in recent years decreased from 50% to approximately 30% as the results of a better selection of patients and increasing experience in their management) may be offset by more durable control of the disease and cure in a certain proportion of patients. Recurrence of underlying malignant disease remains, however, a major problem and is the most common cause of treatment failure following BMT. For this reason, attempts to improve the impact of transplantation are warranted. Options currently under investigation include the development of more effective conditioning regimens, as applied in double auto-transplant or with targeted therapy using antibody-radionuclide conjugates, as well as post-transplant immunomodulation with either IFN-alpha, interleukin-2 or idiotype vaccines. In addition, many other problems regarding BMT for MM are still unresolved and could be properly addressed only in future clinical trials. The most important of these issues include the choice of the best conditioning regimen and the optimal source of haematopoietic stem cells, the nature of relapse after autografting, the need to purge or not to purge the autologous marrow, the existence of a 'graft-versus-myeloma' effect and its role in prolonging the duration of disease control and, finally, the likelihood of cure, especially for patients with molecularly-defined CR.

Prognostic factors in allogeneic bone marrow transplantation for multiple myeloma.

To analyze prognostic factors for allogeneic bone marrow transplantation (BMT) in multiple myeloma. One hundred sixty-two reports of allogeneic matched sibling-donor transplants in multiple myeloma received by the European Group for Blood and Marrow Transplantation (EBMT) registry between 1983 and early 1993 were analyzed for prognostic factors. End points were complete remission, survival, and duration of complete remission. Following BMT, 44% of all patients and 60% of assessable patients entered complete remission. The overall actuarial survival rate was 32% at 4 years and 28% at 7 years. The overall relapse-free survival rate of 72 patients who were in complete remission after BMT was 34% at 6 years. Favorable pretransplant prognostic factors for survival were female sex (41% at 4 years), stage I disease at diagnosis (52% at 4 years), one line of previous treatment (42% at 4 years), and being in complete remission before conditioning (64% at 3 years). The subtype immunoglobulin A (IgA) myeloma and a low beta 2-microglobulin level (< 4 g/L) also tended to have a favorable prognostic impact. The most important post-transplant prognostic factor was to enter a complete remission. Grade III to IV graft-versus-host disease (GVHD) was associated with poor survival. Patients with a low tumor burden who respond to treatment before BMT and are transplanted after first-line therapy have the best prognosis following BMT.

Salvage Therapy for Multiple Myeloma: The University of Arkansas Experience

To summarize a spectrum of salvage regimens for multiple myeloma (MM) developed during the past decade. We reviewed the experience at the University of Arkansas in the management of patients with MM who failed to achieve remission ("primary unresponsive") or had a relapse despite myelosuppressive doses of chemotherapy ("resistant relapse"). Results with use of the various chemotherapeutic protocols are presented, and multivariate regression analysis was applied to determine the independent contributions of certain factors toward event-free and overall survival. The VAD regimen (vincristine sulfate, Adriamycin [doxorubicin hydrochloride], and dexamethasone) yielded responses in 29% of previously unresponsive and 46% of relapsed cases of MM, in comparison with 25% and 21%, respectively, with use of dexamethasone only. Responses occurred more frequently when tumor cell RNA content was high, tumor burden was low, and duration of drug resistance was less than 1 year. The duration of survival in patients who received high doses of melphalan was decreased in those with increased serum levels of lactate dehydrogenase. EDAP (etoposide, dexamethasone, ara-C, and cisplatin) produced 75% or more tumor cytoreduction in 8 of 20 patients. Overall in patients with an increasing number of adverse factors, response rates and survival decreased progressively with less intensive therapy but were unaffected when more intensive therapy was used. In the multivariate analysis, the most important features for extended survival were a low beta 2-microglobulin level before transplantation and application of two bone marrow transplants within 6 months. Variables relative to the patient's overall medical condition, prior treatment, characteristics of MM at diagnosis, and response history should be carefully assessed to determine a plan for salvage therapy that will maximize the opportunity for sustained remission and survival.