Diagnosis and risk stratification in multiple myeloma

Antibody therapies for multiple myeloma

Introduction: Multiple myeloma (MM) is characterized by the uncontrollable proliferation of plasma cells and the excessive production of a specific type of immunoglobulin. Immune system is deregulated in MM and, thus, immunotherapy is a promising therapeutic strategy.Areas covered: The first approach is to use monoclonal antibodies that recognize specific antigens on the surface of myeloma cells, such as CD38 and B-cell maturation antigen. Upon binding to their target, monoclonal antibodies activate the immune cells to destroy the malignant cell. Anti-CD38 molecules as part of highly effective combination regimens have been approved in both newly diagnosed and relapsed/refractory patients and have significantly changed the myeloma treatment landscape in the recent years. Another strategy is to use antibodies that bind both to a molecule on the surface of the myeloma cell and another molecule on the surface of a T-cell (bispecific antibodies). Consecutively, the T-cell comes close to and recognizes the myeloma cell. These have shown promising results in heavily pre-treated patients.Expert opinion: Antibody therapy has significantly enhanced the armamentarium against MM. Further research should focus on tailoring the combination regimens based on disease and patient characteristics in order to optimize the efficacy and safety.

Disease staging according to international scoring system in newly diagnosed patients with multiple myeloma

Objective:

To determine the frequency of disease staging according to international scoring system in patients who are newly diagnosed with Multiple Myeloma (MM) at a tertiary care hospital at Karachi.

Methods:

This single center, non probability consecutive, cross sectional study was conducted from Nov 11, 2015 to May 11, 2016. After taking informed written consent, detailed history was taken and serum β2 microglobulin and albumin levels were checked to assess the study outcome variable i.e. stage of MM. All the collected information was entered in the prescribed performa.

Results:

Eighty newly diagnosed patients with multiple myeloma as per inclusion criteria were included. Sixty seven (83.75%) were male and 13(16.25) were females, with mean age of 58.35+10.077 years. Twenty seven patients (33.75%) were found to have stage-I disease, in 23 (28.75%) stage-II and stage-III in 30 (37.5%).

Conclusion:

Multiple myeloma is relatively common in 5^th decade, with male predominance. International Staging System have great potential for characterizing and stratifying multiple myeloma and revealed a predominance of advanced stage III disease in our setting.

Influence of Clonal Plasma Cell Contamination of Peripheral Blood Stem Cell Autografts on Progression and Survival in Multiple Myeloma Patients After Autologous Peripheral Blood Stem Cell Transplantation in Long-term Observation

BACKGROUND

High-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (auto-PBSCT) remains the mainstay of treatment of eligible patients diagnosed multiple myeloma. The role of clonal plasma cell (CPC) contamination was found as a reason for relapse, but results in terms of survival, progression, and purging were ambiguous. Therefore, the aim of the study was to explore the influence of CPC contamination in the autograft on survival and progression after auto-PBSCT.

STUDY DESIGN

The study included 59 patients diagnosed and treated for multiple myeloma in 1998-2004. Cells with coexpression of CD38⁺⁺⁺CD138⁺⁺CD56⁺ and lacking the expression of CD45, CD19, CD10, CD20, and CD23 were considered CPC in flow cytometry.

RESULTS

The risk of death and progression after auto-PBSCT increased significantly by 10% (P < .021) and 8% (P < .034) per 1 × 10⁶/kg of the CPC number, respectively. For CPC number above 2.96 × 10⁶/kg overall survival achieved clinical significance. Two years after auto-PBSCT, the risk of death was independent of CPC number among the patients who survived (P = .70). Analogous conclusions concerned results of progression-free survival at 1 year after auto-PBSCT.

CONCLUSIONS

High clonal plasma cell contamination (>2.96 ×1 0⁶/kg; 90th percentile of CPC number) is associated with the worst progression-free survival and overall survival. Therefore purging in vitro might be considered for the patients with the highest CPC contamination. Negative consequences of CPC contamination on the risk of death are observed for only 2 years after auto-PBSCT. Thereafter only those patients who had lower CPC contamination survived.

Interferon-gamma in mobilized stem cells: A possible prognostic marker in early post-transplant management in multiple myeloma

INTRODUCTION

A complex network of cytokines in the bone marrow microenvironment has been implicated as an important factor in the pathogenesis of multiple myeloma (MM). Different cytokines have been studied in MM, both in peripheral blood and/or bone marrow, but there are few data correlating cytokines in leukapheresis product with post-transplant response depth to treatment.

MATERIALS AND METHODS

In a retrospective cross-sectional study, levels of tumor necrosis factor alpha (TNF-α), transforming growth factor beta-1 (TGF-β1) and interferon gamma (IFN-γ) in peripheral hematopoietic stem cells/leukapheresis product (PHSC) of patients with MM eligible for transplantation were evaluated. Association of these cytokines with certain factors such as mobilized CD34 + cells/kg, staging, response to treatment and outcome were analyzed.

RESULTS

The median baseline IFN-γ level was 826.4 pg/mL. IFN-γ levels in the leukapheresis product were significantly lower in patients who achieved complete response (CR) three months post-transplant when compared to patients with very good partial response (VGPR) (674.75 ± 80.32 pg/mL versus 939.6 ± 106.8 pg/mL, p = 0.02), respectively. Patients who lost depth of response at the third-month post-transplant had a median level of IFN-γ 1133, being considered "high-expressors" of IFN-γ, while those reaching improved response were called "low-expressors" (median level IFN-γ 485 pg/mL). Overall and progression-free survival did not have a statistically significant correlation with TNF-α, TGF-β1 or IFN-γ, as well as TNF-α and TGF-β1 levels in post-transplant response assessment.

CONCLUSION

IFN-γ in PHSC seems to be an important biomarker of loss of response in MM, suggesting a role in early post-transplant therapeutic management.

CD38-targeting antibodies in multiple myeloma: mechanisms of action and clinical experience

INTRODUCTION

Multiple myeloma (MM) is generally an incurable hematological malignancy with heterogeneous overall survival rates ranging from a few months to more than 10 years. Survival is especially poor for patients who developed disease that is refractory to immunomodulatory drugs and proteasome inhibitors. Areas covered: This review will discuss the importance of CD38-targeting antibodies for the treatment of MM patients to improve their outcome. Expert commentary: Intense immuno-oncological laboratory research has resulted in the development of functionally active monoclonal antibodies against cell surface markers present on MM cells. In this respect, CD38-targeting antibodies such as daratumumab, MOR202, and isatuximab, have high single agent activity in heavily pretreated MM patients by virtue of their pleiotropic mechanisms of action including Fc-dependent effector mechanisms and immunomodulatory activities. Importantly, CD38-targeting antibodies are well tolerated, with infusion reactions as most frequent adverse event. Altogether, this makes them attractive combination partners with other anti-MM agents. Daratumumab is already approved as monotherapy and in combination with lenalidomide-dexamethasone as well as bortezomib-dexamethasone in pretreated MM patients. Furthermore, results from studies evaluating CD38-targeting antibodies in newly diagnosed MM patients are also promising, indicating that CD38-targeting antibodies will be broadly used in MM, resulting in further improvements in survival.

Immunoparesis in newly diagnosed Multiple Myeloma patients: Effects on overall survival and progression free survival in the Danish population

Immunoparesis (hypogammaglobulinemia) is associated to an unfavorable prognosis in newly diagnosed Multiple myeloma (MM) patients. However, this finding has not been validated in an unselected population-based cohort. We analyzed 2558 newly diagnosed MM patients in the Danish Multiple Myeloma Registry representing the entire MM population in Denmark from 2005–2013. Two-thousand two hundred and fifty three patients (90%) presented with reduction below lower normal levels of at least one uninvolved immunoglobulin. Using multivariable Cox regression we found that high age, high ISS score, high LDH and IgA MM were associated to both shorter overall survival and progression free survival. Furthermore, bone marrow plasma cell % was associated to short progression free survival. Immunoparesis had no independent significant effect on OS (HR 0.9 (95%CI: 0.7;1.0; p = 0.12)). Likewise, the number of suppressed immunoglobulins or the relative degree of suppressed uninvolved immunoglobulins from lower normal level (quantitative immunoparesis) was not associated to OS in the multivariable analysis. However, quantitative immunoparesis with at least 25% reduction (from lower normal level) of uninvolved immunoglobulins was associated to shorter PFS for the entire population. The impact of quantitative immunoparesis on PFS was present irrespective of calendar periods 2005–2008 and 2009–2013. Our population-based study does not confirm that immunoparesis at diagnosis is an independent prognostic factor regarding OS. However, quantitative immunoparesis is associated to a shorter PFS.

Identification and expression of MMSA-8, and its clinical significance in multiple myeloma

In our previous studies, we identified 12 multiple myeloma (MM)-associated antigens by serological analysis of tumor-associated antigens with a recombinant cDNA expression library (SEREX) on MM. MM-associated antigen-8 (MMSA-8) was one of the new antigens identified. We determined the 3′- and 5′-ends of MMSA-8 using SMART-rapid amplification of cDNA ends (RACE) and then cloned its full-length cDNA in the U266 cell line. The full cDNA sequence revealed that MMSA-8 is RPS27A-related transcript variant 1 that is specifically associated with MM. We examined its prognostic significance for the first time, by investigating the correlations between MMSA-8 expression and definite clinicopathological features. We quantitatively assessed MMSA-8 expression using qRT-PCR and western blot analysis in healthy donors and MM patients. The expression levels of MMSA-8 were upregulated with statistical significance in MM patients in contrast to those in healthy donors. The expression of MMSA-8 was also upregulated in relapsed patients compared with that in the complete remission (CR) group. Contrasting MMSA-8 expression levels in different patients with definite clinicopathological features suggested an association between MMSA-8 with unfavorable clinicopathological characteristics, such as international staging system (ISS) stage III, higher lactate dehydrogenase (LDH) levels and higher C-reactive protein (CRP) levels. The expression of MMSA-8 was also increased in patients with unfavorable cytogenetic and genetic abnormalities, including the presence of t(11;14), t(4;14), t(14;16), del(17p), del(13q) and p53 deletion, which was statistically significant. The expression of MMSA-8 exhibited significant variance in the treatment responses of the CR, PR, progression and relapse groups. Univariate and multivariate analyses revealed that high MMSA-8 values were associated with poorer progression-free survival (PFS) and overall survival (OS) in MM patients independently. In conclusion, our data indicated that MMSA-8 is an independent and unfavorable prognostic risk factor in MM; MMSA-8 is also a promising diagnostic and therapeutic target in MM patients, but further validation is needed.

Geriatric assessment in multiple myeloma patients: validation of the International Myeloma Working Group (IMWG) score and comparison with other common comorbidity scores

This first validation of the International Myeloma Working Group geriatric assessment in 125 newly diagnosed multiple myeloma patients was performed using the International Myeloma Working Group score based on age, the Charlson Comorbidity Index and cognitive and physical conditions (Activities of Daily Living / Instrumental Activities of Daily Living) to classify patients as fit, intermediate-fit or frail. We verified the International Myeloma Working Group score's impact on outcome, and whether additional tools complement it. Since our prior analyses determined renal, lung and Karnofsky performance impairment as multivariate risks, and the inclusion of frailty, age and cytogenetics complements this, we included the revised myeloma comorbidity index, the Charlson Comorbidity Index, the Hematopoietic Cell Transplantation-Comorbidity Index and the Kaplan-Feinstein Index in this assessment. Multivariate analysis confirmed cytogenetics, Activities of Daily Living, Instrumental Activities of Daily Living and the Charlson Comorbidity Index as risks: 3-year overall survival for fit, intermediate-fit and frail patients was 91%, 77% and 47%, respectively. Using the Charlson Comorbidity Index, the Hematopoietic Cell Transplantation-Comorbidity Index, the Kaplan-Feinstein Index and the revised Myeloma Comorbidity Index allowed us to define fit and frail patients with distinct progression-free and overall survival rates, with the most pronounced differences evidenced via the International Myeloma Working Group score, the Charlson Comorbidity Index and the revised Myeloma Comorbidity Index. Since the Charlson Comorbidity Index is included in the International Myeloma Working Group score, we propose the latter and the revised Myeloma Comorbidity Index for future frailty measurements. Both are useful instruments for identifying myeloma patients with a geriatric risk profile and have a strong prognostic value for functional decline and overall survival. The study was registered as: (clinicaltrials.gov Identifier: 00003686).

Section E6.1-6.4 of the ACMG technical standards and guidelines: chromosome studies of neoplastic blood and bone marrow-acquired chromosomal abnormalities

DISCLAIMER

These American College of Medical Genetics and Genomics standards and guidelines are developed primarily as an educational resource for clinical laboratory geneticists to help them provide quality clinical laboratory genetic services. Adherence to these standards and guidelines is voluntary and does not necessarily ensure a successful medical outcome. These standards and guidelines should not be considered inclusive of all proper procedures and tests or exclusive of other procedures and tests that are reasonably directed to obtaining the same results. In determining the propriety of any specific procedure or test, the clinical laboratory geneticist should apply his or her own professional judgment to the specific circumstances presented by the individual patient or specimen. Clinical laboratory geneticists are encouraged to document in the patient's record the rationale for the use of a particular procedure or test, whether or not it is in conformance with these standards and guidelines. They also are advised to take notice of the date any particular guideline was adopted, and to consider other relevant medical and scientific information that becomes available after that date. It also would be prudent to consider whether intellectual property interests may restrict the performance of certain tests and other procedures.Cytogenetic analyses of hematological neoplasms are performed to detect and characterize clonal chromosomal abnormalities that have important diagnostic, prognostic, and therapeutic implications. At the time of diagnosis, cytogenetic abnormalities assist in the diagnosis of such disorders and can provide important prognostic information. At the time of relapse, cytogenetic analysis can be used to confirm recurrence of the original neoplasm, detect clonal disease evolution, or uncover a new unrelated neoplastic process. This section deals specifically with the standards and guidelines applicable to chromosome studies of neoplastic blood and bone marrow-acquired chromosomal abnormalities. This updated Section E6.1-6.4 has been incorporated into and supersedes the previous Section E6 in Section E: Clinical Cytogenetics of the 2009 Edition (Revised 01/2010), American College of Medical Genetics and Genomics Standards and Guidelines for Clinical Genetics Laboratories.Genet Med 18 6, 635-642.

Monoclonal antibodies targeting CD38 in hematological malignancies and beyond

CD38 is a multifunctional cell surface protein that has receptor as well as enzyme functions. The protein is generally expressed at low levels on various hematological and solid tissues, while plasma cells express particularly high levels of CD38. The protein is also expressed in a subset of hematological tumors, and shows especially broad and high expression levels in plasma cell tumors such as multiple myeloma (MM). Together, this triggered the development of various therapeutic CD38 antibodies, including daratumumab, isatuximab, and MOR202. Daratumumab binds a unique CD38 epitope and showed strong anti-tumor activity in preclinical models. The antibody engages diverse mechanisms of action, including complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, programmed cell death, modulation of enzymatic activity, and immunomodulatory activity. CD38-targeting antibodies have a favorable toxicity profile in patients, and early clinical data show a marked activity in MM, while studies in other hematological malignancies are ongoing. Daratumumab has single agent activity and a limited toxicity profile, allowing favorable combination therapies with existing as well as emerging therapies, which are currently evaluated in the clinic. Finally, CD38 antibodies may have a role in the treatment of diseases beyond hematological malignancies, including solid tumors and antibody-mediated autoimmune diseases.

Multiple Myeloma: Treatment is Getting Individualized

Multiple myeloma (MM) is a heterogeneous disease with varied outcome. The novel agents including two major classes of drugs; the immunomodulatory drugs and the proteasome inhibitors with unprecedented response rates, have replaced conventional chemotherapy. With monoclonal antibodies on the horizon, outcome of this disorder will further improve. Progression in risk stratification systems has made it possible to predict the disease course as well as outcome in myeloma patients with disease categorization into low to high risk. In addition, detection of minimal residual disease by serum free light chain assay, flow cytometry, molecular techniques like polymerase chain reaction and positron emission tomography scan is playing an important role in modifying the treatment. An extensive research in the disease biology has improved our knowledge regarding interplay between myeloma cells and elements of the bone marrow microenvironment which contribute to sustain proliferation and survival as well as de novo drug resistance. Again, insight into the role of genetic and epigenetic interactions in MM has exposed new molecular targets. All these have opened the gateway for novel therapeutic strategies with focus on risk based individualized therapy.

MMSA-1 expression pattern in multiple myeloma and its clinical significance

Multiple myeloma-associated antigen-1 (MMSA-1) is a novel multiple myeloma (MM)-associated antigen which has been recently identified. Herein, we have tried to examine its clinical significance by studying the relationship between its expression and selected clinicopathological features. We extracted mononuclear cells from the bone marrow of MM patients and healthy donors and compared the MMSA-1 expression by RT-PCR and Western blot analysis. In addition, we also analyzed MMSA-1 expression in patients that were grouped based on selected clinical parameters. Moreover, the impact of MMSA-1 on patients' survival was also explored. MMSA-1 mRNA and protein were significantly upregulated in MM patients in comparison with healthy donors. Moreover, among the newly diagnosed and relapsed/refractory patients, the MMSA-1 expression was higher in relapsed/refractory patients. In addition, MMSA-1 mRNA expression not only showed significantly higher correlation with clinical parameters such as age, Durie and Salmon stage, bone lesion condition, albumin, creatinine and lactate dehydrogenase but also has a close relationship with myeloma bone disease-related cytokines, genetic abnormalities and treatment response. Multivariate COX analysis predicted MMSA-1 and LDH levels to be independently associated with a poor progression-free survival and overall survival in myeloma patients. Our findings provide initial proof of concept that MMSA-1 is a potent gene that is specifically expressed in MM patients and could be a feasible biomarker and independent prognostic factor.

Anti-tumor activity of the proteasome inhibitor BSc2118 against human multiple myeloma

Introduction of bortezomib, the first generation of proteasome inhibitor, has significantly improved the median overall survival of patients with multiple myeloma (MM). However, the dose-limiting adverse events and acquired drug resistance limit its long-term usage. Here, we report in vitro and in vivo anti-MM activity of the irreversible proteasome inhibitor BSc2118. BSc2118 inhibited the chymotrypsin-like (CT-L) proteasome activity, accompanied by accumulation of ubiquitinated proteins. BSc2118 suppressed tumor cell growth through induction of G2/M phase arrest and induced apoptosis via activation of the apoptotic signaling cascade, in association with up-regulation of p53 and p21. Importantly, BSc2118 was active in vitro against MM cells' acquired bortezomib resistance. Of note, BSc2118 also displayed a novel anti-angiogenesis activity both in vitro and in vivo. Lastly, BSc2118 exhibited a broader safety dose range and higher anti-tumor efficacy in vivo in a human MM xenograft mouse model, compared to bortezomib. Together, these findings indicate the in vitro and in vivo anti-MM activities of BSc2118 through induction of cell cycle arrest and apoptosis, as well as inhibition of tumor angiogenesis. They also suggest that BSc2118 might, at least in vitro, partially overcome acquired bortezomib resistance, likely associated with inhibition of autophagy.