Multiple myeloma: an update

Exceptional Manifestation of Multiple Myeloma

Despite being a rare occurrence, multiple myeloma (MM) has been reported as an alternative cause of pleurisy, with approximately 50 documented cases in the literature so far. In this case report, we present the clinical scenario of a patient who sought medical attention due to symptoms of dyspnea, chest pain, and weight loss. Through a comprehensive diagnostic evaluation, it was determined that the patient's pleural involvement was attributable to MM, a hematological malignancy. This case highlights the importance of considering MM as a potential etiology in patients presenting with pleural manifestations, even in settings where tuberculosis is the prevailing cause.

Multiple myeloma with plasmacytoma of the clivus bone presenting with multiple cranial nerve III, IV, and VI palsy: A diagnostic dilemma

Central nervous system (CNS) manifestation with cranial nerve palsy in multiple myeloma (MM) is a rare manifestation. Plasmacytoma originates from the bones of the skull base in 3% patients with MM but rarely develops from the soft tissues of the nasal cavity and paranasal sinuses. Here, we present a case of 68-year-old male patient with multiple myeloma, clivus bone plasmacytoma, and cavernous sinus syndrome.

The Burden of a Multiple Myeloma Diagnosis on Patients and Caregivers in the First Year: Western European Findings

Background

This research aimed to quantify the burden of illness (BoI) in transplant eligible (TE) and transplant non-eligible (TNE) newly diagnosed multiple myeloma (NDMM) patients and their caregivers, in the first year after diagnosis: at months 0, 3, and 12.

Methods

Prospective, cross-sectional, observational NDMM study of TE and TNE patients and their caregivers from France, Germany, Italy, and Spain was conducted between May 2019 and January 2021. A structured, online questionnaire measuring disease burden, direct and costs, out-of-pocket expenses, and health-related quality of life (HRQoL) was used. Descriptive statistics were performed.

Results

A total of 164, 160, and 190 NDMM patients [>65 years; self-described healthy; not working; living with caregiver] answered at months 0, 3, and 12. Patients lost independence to perform daily activities; mean pain intensity rose and opioid utilization increased, more significantly among TNE patients. Overall health status and HRQoL remained stable. Median 3-month direct medical costs peaked at month 3. Specialist consultations and hospital admissions were the greatest cost amongst TE and TNE patients. Home adaptations increased out-of-pocket expenditures amongst TNE patients. Patients describing themselves as working spent a median 0 hours in the office at all time points. A total of 131, 122, and 124 caregivers answered at months 0, 3, and 12. Mean self-rated burden score rose. By month 12, half of caregivers developed stress, anxiety or depression. Most employed caregivers continued working. Productivity was low at month 0 with a trend of recovering at month 12. Caregivers of TNE compared to TE patients reported greater time burden. Caregivers' HRQoL was stable over time.

Conclusion

NDMM is burdensome for patients and caregivers in the first year after diagnosis. TNE patients are more dependent on caregivers and incur higher care costs than TE patients. Despite the financial, physical, and emotional burden, HRQoL remains stable possibly indicating resilience and illness adjustment amongst patients and caregivers.

Causal relationships between inflammatory factors and multiple myeloma: A bidirectional Mendelian randomization study

Changes in serum inflammatory factors occur throughout the onset and multiple myeloma (MM) progression, the feedback loops make it harder to distinguish between causes and effects. In the present study, we performed a bidirectional summary-level Mendelian randomization (MR) analysis to elucidate the causal relationships of C-reactive protein (CRP) and inflammatory regulators with MM. Summary-level data of genetic variants associated with inflammation were extracted from two genome-wide association studies (GWASs) on CRP and human cytokines, while data on MM was from large meta-analyses of GWASs among 372 617 UK Biobank participants. The inverse-variance weighted (IVW) method was used as the primary MR analysis and MR-Egger, weighted median, and MR-pleiotropy residual sum and outlier (MR-PRESSO) were used as the sensitivity analyses. Our results suggested that higher levels of monocyte-specific chemokine-3 (IVW estimate odds ratio [OR_IVW ] per SD genetic cytokines change: 1.24; 95% confidence interval [CI]: 1.03-1.49; P = .02), vascular endothelial growth factor (1.14, 1.03-1.27; P = .02), interleukin-10 (1.33, 1.01-1.75; P = .04) and interleukin-7 (1.24, 1.03-1.48; P = .02) were associated with increased risk of MM, while lower levels of tumor necrosis factor-β (0.84, 0.74-0.92; P < .001) was strongly associated with an increased risk of MM. And conversely, genetically predicted MM was related to increased levels of interleukin-17 (IVW estimate β: 0.051, 95% CI: 0.018-0.085; P = 2.7 × 10^-3 ). Besides, we observed no such significant associations for other inflammatory factors in our study. Overall, our study provides genetic evidence on the relationships of CRP and systemic inflammatory regulators with MM. Targeted interventions of specific inflammatory factors may have implications to alleviate MM cancer risk.

Is comprehensive geriatric testing guiding in the identification of multiple myeloma patients who are candidates for autologous stem cell transplantation? A prospective analysis

Multiple myeloma (MM) is a hematological malignancy of older adults. This study aimed to investigate the differences in performance, comorbidity scores, and comprehensive geriatric assessment (CGA) before and after induction therapy in newly diagnosed MM patients, as well as the factors that may be associated with improved performance status after induction therapy. Thirty-seven consecutive patients aged 50 years and older, who were newly diagnosed with MM, were included in the study. The patients underwent performance status evaluation and CGA when first diagnosed and after 4 cycles of induction chemotherapy. The performance status of 11 patients (40.7%) changed after induction therapy. Improvement in performance status was significantly lower in patients who were frail according to the Fried frailty criteria and IMWG scores (60% vs. 25%, p = 0.04), (30.0% vs. 6.2%, p = 0.02), taking more than 2 medications due to comorbidities (p = 0.01, confidence interval 0.06-0.09) and those with renal involvement (80.0% vs. 18.7%, p = 0.002). Those with bone involvement were more prevalent among the patients whose performance status improved (87.5% and 50.0%, p = 0.03). This study demonstrated that performance status might improve after induction therapy. Results suggest that CGA before induction therapy can predict performance status change. These results might have implications for predicting at the time of diagnosis, whether an MM patient can be a transplant candidate after induction therapy.

Atypical multiple myeloma in 3 young dogs

Three dogs under 12 months old were diagnosed with atypical multiple myeloma (MM), having an aggressive multifocal anaplastic round cell sarcoma in bone marrow, viscera, and/or peripheral blood, which were confirmed by cytology and immunohistochemistry to be of plasma cell origin. The intramedullary sarcomas caused myelophthisis, osteolysis, and hypercalcemia. Complete or free light chain monoclonal gammopathy in the serum and/or urine was demonstrated by protein electrophoresis and immunofixation. The polymerase chain reaction for antigen receptor rearrangement assay performed on 2 cases identified a clonally rearranged immunoglobulin gene. Neoplastic cells lacked expression of CD45, CD3, CD18, CD21, CD34, and MHCII by flow cytometry. Immunohistochemistry revealed MUM1 immunoreactivity of the neoplastic cells. Combining all data, the diagnosis was MM. An aggressive form of MM in young dogs should be a differential diagnosis for patients with an immunoglobulin-productive, B cell-clonal, CD45-negative, MUM1-positive discrete cell neoplasm arising from the bone marrow.

Bone-Targeted Bortezomib Inhibits Bortezomib-Resistant Multiple Myeloma in Mice by Providing Higher Levels of Bortezomib in Bone

Limited treatment options exist for cancer within the bone, as demonstrated by the inevitable, pernicious course of metastatic and blood cancers. The difficulty of eliminating bone-residing cancer, especially drug-resistant cancer, necessitates novel, alternative treatments to manipulate tumor cells and their microenvironment, with minimal off-target effects. To this end, bone-targeted conjugate (BP-Btz) was generated by linking bortezomib (Btz, an anticancer, bone-stimulatory drug) to a bisphosphonate (BP, a targeting ligand) through a cleavable linker that enables spatiotemporally controlled delivery of Btz to bone under acidic conditions for treating multiple myeloma (MM). Three conjugates with different linkers were developed and screened for best efficacy in mouse model of MM. Results demonstrated that the lead candidate BP-Btz with optimal linker could overcome Btz resistance, reduced tumor burden, bone destruction, or tumor metastasis more effectively than BP or free Btz without thrombocytopenia and neurotoxicity in mice bearing myeloma. Furthermore, pharmacokinetic and pharmacodynamic studies showed that BP-Btz bound to bone matrix, released Btz in acidic conditions, and had a higher local concentration and longer half-life than Btz in bone. Our findings suggest the potential of bone-targeted Btz conjugate as an efficacious Btz-resistant MM treatment mechanism. © 2021 American Society for Bone and Mineral Research (ASBMR).

Multiple myeloma in Lebanon: Trend analysis, 10-year projections and comparisons to other countries

BACKGROUND

Multiple myeloma (MM) is a common hematological malignancy in aging populations. This study aims to inspect the trends from 2005 to 2016 and future projections of MM in Lebanon and to compare its incidence-rates to other MENA and non-MENA countries.

METHODS

The data concerning MM cases over the studied period was extracted from the National Cancer Registry (NCR) of Lebanon. The online database "Cancer Incidence in Five Continents" was screened and data of other countries were collected. The age-specific and age-standardized incidence rates (ASR(w)) were computed and analyzed using Joinpoint regression. 10 year projections were predicted by employing a logarithmic model.

RESULTS

During the time period 2005-2016, MM was significantly more common in males. Both genders had a cancer peak in patients older than 75 years. MM demonstrated a significantly increasing trend in both genders over the 12 years of study. Compared to other countries in the MENA region, Lebanon ranked first in females and second in males, while it came among the lowest when compared to randomly selected developed countries from non-MENA regions. Projecting to 2026, incidence rates of MM in Lebanon are expected to rise in both males and females.

CONCLUSION

Incidence of MM in Lebanon is continually rising. The elderly population, especially males, is much more affected than the younger one. Different risk factors, specifically obesity and toxic exposures, can explain the escalating burden of MM among the population. A collaboration of efforts between the government and health organization is expected for an effective disease control.

Hematuria - Look beyond the Urinary Tract - A Rare Case Report

The major causes of hematuria in a middle-aged female include infections, renal calculi, or structural abnormalities of the urinary tract. Most patients are investigated and treated on an outpatient basis. While a possibility of malignancy of the bladder or kidneys may also be considered, hematological malignancy is an uncommon cause of hematuria. Detailed evaluation is important to rule out malignancy in new-onset hematuria. We report a case of a 49-year-old female who presented with gross hematuria, later diagnosed to have multiple myeloma (MM), despite the absence of its classical symptoms. This unusual presentation reaffirms its status as “The Great Masquerader.” The case is worth highlighting because gross hematuria as the first presentation of MM is uncommon. The author wishes to stress that the clinician should also suspect blood dyscrasias with associated coagulation abnormalities in the workup of gross hematuria.

Bisphosphonates for delivering drugs to bone

Advances in the design of potential bone-selective drugs for the treatment of various bone-related diseases are creating exciting new directions for multiple unmet medical needs. For bone-related cancers, off-target/non-bone toxicities with current drugs represent a significant barrier to the quality of life of affected patients. For bone infections and osteomyelitis, bacterial biofilms on infected bones limit the efficacy of antibiotics because it is hard to access the bacteria with current approaches. Promising new experimental approaches to therapy, based on bone-targeting of drugs, have been used in animal models of these conditions and demonstrate improved efficacy and safety. The success of these drug-design strategies bodes well for the development of therapies with improved efficacy for the treatment of diseases affecting the skeleton. LINKED ARTICLES: This article is part of a themed issue on The molecular pharmacology of bone and cancer-related bone diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.9/issuetoc.

Tumours of the odontoid peg revisited

Introduction

Tumours of the odontoid peg are rare but can potentially cause significant morbidity and mortality.

Methods

A retrospective review of oncology and radiology database of tertiary orthopaedic oncology centre for all lesions affecting the odontoid peg over the last 12 years was performed.

Results

We identified a total of 15 tumours involving the odontoid peg, majority being malignant. Myeloma was the most common tumour.

Conclusion

Tumours of the odontoid peg are rare. Spinal surgeons and Radiologists need to be aware of them.

Toxicities of Chimeric Antigen Receptor T Cell Therapy in Multiple Myeloma: An Overview of Experience From Clinical Trials, Pathophysiology, and Management Strategies

In the last few years, monoclonal antibodies (mAbs) such as elotuzumab and daratutumab have brought the treatment of multiple myeloma (MM) into the new era of immunotherapy. More recently, chimeric antigen receptor (CAR) modified T cell, a novel cellular immunotherapy, has been developed for treatment of relapsed/refractory (RR) MM, and early phase clinical trials have shown promising efficacy of CAR T cell therapy. Many patients with end stage RRMM regard CAR T cell therapy as their “last chance” and a “hope of cure”. However, severe adverse events (AEs) and even toxic death related to CAR T cell therapy have been observed. The management of AEs related to CAR T cell therapy represents a new challenge, as the pathophysiology is not fully understood and there is still no well-established standard of management. With regard to CAR T cell associated toxicities in MM, in this review, we will provide an overview of experience from clinical trials, pathophysiology, and management strategies.

Prognosis of medication-related osteonecrosis of the jaws in cancer patients using antiresorptive agent zoledronic acid

BACKGROUND/PURPOSE

Anti-resorptive agents are commonly used in cancer patients with bone metastasis or multiple myeloma (MM). An adverse event termed medication-related osteonecrosis of the jaws (MRONJ) was discovered in patients using these agents but relatively little attention has been paid to its prognosis. Our aims were to find out the treatment outcomes and prognostic indicators of MRONJ in cancer patients who received zoledronic acid as antiresorptive therapy.

METHODS

We retrospectively surveyed a cohort of 133 cancer patients who received zoledronic acid. A total of 150 MRONJ lesions were included for investigation. Cumulative complete response rate after treatment was calculated with the Kaplan-Meier method, and significance was examined with the log-rank tests. Cox regression was used for univariate and multivariate analyses of prognostic factors.

RESULTS

The cumulative complete response rate of all patients at 24 months was 53.2%, and those of patients with MM, breast cancer and prostate cancer were 27.8%, 60.7% and 68.0%, respectively. Having MM was identified as an independent prognostic factor in a multivariate analysis with adjusted hazard ratios of 0.28 (95% confidence interval, 0.09-0.83).

CONCLUSION

For cancer patients with ONJ related to zoledronic acid, patients with MM endure a worse treatment outcome.

Development of Label-Free Impedimetric Immunosensors for IKZF1 and IKZF3 Femtomolar Detection for Monitoring Multiple Myeloma Patients Treated with Lenalidomide

Lenalidomide is an immunomodulatory drug (IMiD) used to treat multiple myeloma (MM) patients. Lenalidomide destroys MM cells by inducing ubiquitination and the consequent degradation of Ikaros family zinc finger proteins 1 and 3 (IKZF1 and IKZF3). High expression of IKZF1 and IKZF3 in MM results in less sensitivity to lenalidomide treatment and possible cytotoxic effect. Therefore, detecting the expression of IKZF1 and IKZF3 proteins is of utmost importance in the treatment of MM. Here, we report the fabrication of a novel label-free electrochemical immunosensor for the rapid detection and quantification of IKZF1 and IKZF3 using electrochemical impedance spectroscopy (EIS). Gold electrodes were used to fabricate the immunosensors by immobilizing IKZF1 and IKZF3 specific antibodies using cysteamine and PDITC crosslinkers. The immunosensors were able to detect IKZF1 and IKZF3 protein levels with respective low detection limits of 0.68 and 0.97 pg/ml (11.8 and 16.7 fM). Furthermore, the immunosensors’ successful application in human serum and their high selectivity and sensitivity enables their possible application in other biofluids as simple point-of-care devices for monitoring multiple myeloma patients treated with lenalidomide, to prevent the drug’s cytotoxicity and minimize its side effects.

Bleeding diathesis in canine multiple myeloma and prognostic implications: A cohort study in 156 dogs

Multiple myeloma (MM) is a tumor of plasma cells representing approximately 1% of all canine tumors. Clinical evident bleeding is often referred to as the main finding. The aim of the study was to evaluate the occurrence of clinical bleedings in dogs with MM and its prognostic implications compared to a population of dogs not affected by MM. Two groups of dogs (# 78 each) individually matched for breed, age and gender were considered. Group-1 (exposed) was affected by MM and group-2 (unexposed) was affected by other diseases. They were compared for bleeding and mortality at 90 days after diagnosis (relative risk, RR; attributable risk, AR). Among group-1, bleeding patients (B) were compared with non-bleeding patients (NB) in terms of mortality at 90 days (RR, AR). Incident cases of MM were 78/57,694 (0.13%). Signs of bleeding up to 30 days before the referral presentation were found in 33 (42.3%) group-1 dogs in comparison to 6 (7.7%) group-2 dogs (RR, 5.50, CI 95% 2.55-12.3, p = 0.0001; AR, 0.34, CI 95% 0.22-0.47, p = 0.0001). Epistaxis was the most frequent sign of bleeding recorded. Nineteen dogs from group-1 (24.3%) and eight from group-2 (10.2%) were non-survivors (RR = 2.37, CI 95% 1.14-5.06, p = 0.01; AR = 0.14, CI 95% 0.02-0.26, p = 0.01). Among the group-1, the B dogs, 4/33 (12.1%) were non-survivors, while 15/45 NB dogs (33.3%) were non-survivors (RR = 2.75, CI 95% 1.08-7.44, p = 0.03; AR = 0.21, CI 95% 0.20-0.38, p = 0.03). Epistaxis at diagnosis was frequent in MM dogs, and signs of bleeding were associated with a more favorable 90-day prognosis.

Autologous Peripheral Blood Stem Cell Transplantation Among Lymphoproliferative Disease Patients: Factors Influencing Engraftment

Objectives

Autologous peripheral blood stem cells transplantation (APBSCT) is a therapeutic option which can be used in various hematological, neoplastic disorders including lymphoproliferative disease (LPD). Differences in patient populations and treatment modalities in different transplant centers mean it is important to improve the knowledge of the different factors affecting engraftment after APBSCT for the success of this procedure. We sought to determine the factors influencing neutrophil and platelet engraftment after APBSCT in patients with LPD.

Methods

We conducted a retrospective review of 70 patients with LPD (35 with lymphoma and 35 with multiple myeloma) who had undergone APBSCT between January 2008 and December 2016. Data obtained included disease type, treatment, and stem cell characteristics. Kaplan-Meier analysis was performed for probabilities of neutrophil and platelet engraftment occurred and was compared by the log-rank test. The multivariate Cox proportional hazards regression model was used for the analysis of potential independent factors influencing engraftment. A p-value < 0.050 was considered statistically significant.

Results

Most patients were ethnic Malay, the median age at transplantation was 49.5 years. Neutrophil and platelet engraftment occurred in a median time of 18 (range 4–65) and 17 (range 6–66) days, respectively. The majority of patients showed engraftment with 65 (92.9%) and 63 (90.0%) showing neutrophil and platelet engraftment, respectively. We observed significant differences between neutrophil engraftment and patient’s weight (< 60/≥ 60 kg), stage of disease at diagnosis, number of previous chemotherapy cycles (< 8/≥ 8), and pre-transplant radiotherapy. While for platelet engraftment, we found significant differences with gender, patient’s weight (< 60/≥ 60 kg), pre-transplant radiotherapy, and CD34+ dosage (< 5.0/≥ 5.0 × 10⁶/kg and < 7.0/≥ 7.0 × 10⁶/kg). The stage of disease at diagnosis (p = 0.012) and pre-transplant radiotherapy (p = 0.025) were found to be independent factors for neutrophil engraftment whereas patient’s weight (< 60/≥ 60 kg, p = 0.017), age at transplantation (< 50/≥ 50 years, p = 0.038), and CD34+ dosage (< 7.0/≥ 7.0 × 10⁶/kg, p = 0.002) were found to be independent factors for platelet engraftment.

Conclusions

Patients with LPD who presented at an early stage and with no history of radiotherapy had faster neutrophil engraftment after APBSCT, while a younger age at transplantation with a higher dose of CD34+ cells may predict faster platelet engraftment. However, additional studies are necessary for better understanding of engraftment kinetics to improve the success of APBSCT.

Abducens Nerve Palsy as Initial Presentation of Multiple Myeloma and Intracranial Plasmacytoma

Central Nervous System (CNS) involvement in multiple myeloma and/or multifocal solitary plasmacytoma is rare. Although they are unique entities, multiple myeloma (MM) and plasmacytoma represent a spectrum of plasma cell neoplastic diseases that can sometimes occur concurrently. Plasmacytomas very often present as late-stage sequelae of MM. In this case report, we report a 53-year-old female presenting with right abducens cranial nerve (CN) VI palsy as an initial presentation secondary to lesion of the right clivus.

Multiple Myeloma Baseline Immunoglobulin G Level and Pneumococcal Vaccination Antibody Response

Infections are a major cause of morbidity and mortality in multiple myeloma (MM), a cancer of the immune system. Vaccination clinical efficacy endpoints have not been demonstrated, and there are limited data on surrogate markers of efficacy. This pilot study evaluated sequential immunologic markers after standard pneumococcal vaccination (PV) in patients with MM and non-MM controls. Vaccination was standard for PV (PCV13 or PPV23), with laboratory testing at baseline and at 2, 4, 12 and 24 weeks after vaccination. Immunoglobulin G (IgG) antibodies to pneumococcal antigens were detected by ELISA. Prevaccination total IgG levels and IgG subclass levels were also measured by ELISA. Four of 6 controls responded with at least a 2-fold increase in antibody concentration; only 2 controls had a sustained increase in concentration. Six of 8 patients with MM had at least a 2-fold antibody increase; however, only 2 of these patients showed a sustained increase of antipneumococcal antibody. Response rate differences were not statistically significant in this small pilot, and there was no relationship between responsiveness to PV and initial serum total IgG levels or IgG subclasses at study entry. Future prospective studies are needed to ascertain the immunological and clinical efficacy and effectiveness of various vaccines and vaccination strategies in MM.

Relapse of Multiple Myeloma Presenting as Lower Lip Numbness

Multiple myeloma (MM) is an uncommon malignancy characterised by the proliferation of clonal plasma cells. There are few published reports describing the extramedullary presentation of MM manifesting primarily in the head and neck region. In addition, the occurrence of an isolated relapse of MM in these sites is exceedingly rare. We report a 56-year-old female who presented to the Sultan Qaboos University Hospital, Muscat, Oman, in 2010 with sudden-onset numbness of the lower lip. She had a history of MM in remission following chemotherapy and a bone marrow transplant. Clinical and radiographic examinations were indicative of a possible relapse of MM, which was subsequently confirmed by bone marrow aspiration and histopathological evaluation. This unique case highlights the unusual site of relapse of a haematolymphoid malignancy.

Vaccination in Multiple Myeloma: Review of Current Literature

Multiple myeloma is a cancer of the immune system. Infection is a major cause of morbidity and mortality in patients with multiple myeloma. Some of these infections are preventable by vaccines available to the general population. However, little is known about the clinical effectiveness of these vaccines in patients with multiple myeloma, and the cellular and humoral immune response to vaccination has not been well characterized, especially in conjunction with modern myeloma therapies. The present report reviews the basics of multiple myeloma and the immune system, the available evidence on the immunologic response of patients with multiple myeloma after vaccination, and current practice recommendations regarding specific vaccines. Understanding the immune response to vaccines could help us understand how immuno-oncology-based therapies work in multiple myeloma and provide future directions for research.

PTTG1 expression is associated with hyperproliferative disease and poor prognosis in multiple myeloma

Background

Multiple myeloma (MM) is an incurable haematological malignancy characterised by the clonal proliferation of malignant plasma cells within the bone marrow. We have previously identified pituitary tumour transforming gene 1 (Pttg1) as a gene that is significantly upregulated in the haematopoietic compartment of the myeloma-susceptible C57BL/KaLwRij mouse strain, when compared with the myeloma-resistant C57BL/6 mouse. Over-expression of PTTG1 has previously been associated with malignant progression and an enhanced proliferative capacity in solid tumours.

Methods

In this study, we investigated PTTG1 gene and protein expression in MM plasma cells from newly diagnosed MM patients. Gene expression profiling was used to identify gene signatures associated with high PTTG1 expression in MM patients. Additionally, we investigated the effect of short hairpin ribonucleic acid (shRNA)-mediated PTTG1 knockdown on the proliferation of the murine myeloma plasma cell line 5TGM1 in vitro and in vivo.

Results

PTTG1 was found to be over-expressed in 36–70 % of MM patients, relative to normal controls, with high PTTG1 expression being associated with poor patient outcomes (hazard ratio 2.49; 95 % CI 1.28 to 4.86; p = 0.0075; log-rank test). In addition, patients with high PTTG1 expression exhibited increased expression of cell proliferation-associated genes including CCNB1, CCNB2, CDK1, AURKA, BIRC5 and DEPDC1. Knockdown of Pttg1 in 5TGM1 cells decreased cellular proliferation, without affecting cell cycle distribution or viability, and decreased expression of Ccnb1, Birc5 and Depdc1 in vitro. Notably, Pttg1 knockdown significantly reduced MM tumour development in vivo, with an 83.2 % reduction in tumour burden at 4 weeks (p < 0.0001, two-way ANOVA).

Conclusions

This study supports a role for increased PTTG1 expression in augmenting tumour development in a subset of MM patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-015-0209-2) contains supplementary material, which is available to authorized users.

The prognostic role of bone turnover markers in multiple myeloma patients: The impact of their assay. A systematic review and meta-analysis

BACKGROUND

Multiple myeloma (MM) is characterized by the progressive destruction of bone tissue due to the uncontrolled proliferation of the immunoglobulins. The detection of bone turnover markers (BTMs) may represent a non-invasive method to assess the bone involvement and to predict the risk of bone morbidity. This systematic review evaluates clinical utility of changes in BTMs levels in MM patients and their prognostic role.

METHODS

We searched Medline, Embase, WOS and Scopus. All eligible articles were examined and the risk of bias was evaluated. Results about PICP, PINP, ICTP, OC, CTX, NTX, RANKL and OPG were extracted. Weighted mean difference, risk ratio and hazard ratio were pooled.

RESULTS

Thirty studies and more than 2500 patients were included in this systematic review. The majority of them (50%) used ELISA to quantify BTMs, 10 of them used RIA and only 4 did not report the information regarding the type of immunoassays. In MM patients, the concentration of NTX and ICTP increased, instead the concentrations of BAP and OC lowered when compared to healthy subjects. High levels of ICTP were predictive of bone events (RR 1.18) and they were associated to poor survival (HR 1.08). Most of the included studies were considered at high risk of bias, in fact the reporting of the results was often incomplete. Between-studies heterogeneity was high.

CONCLUSIONS

BTMs measurement may be very useful in the management of MM patients, especially to evaluate the bone disease progression. They could help clinicians to identify patients at high risk of bone events and to opt for more appropriate therapy; nevertheless their high biological and analytical variability limit their implementation in clinical practice.