Clinical Utility of Biochemical Markers of Bone Metabolism for Improving the Management of Patients with Advanced Multiple Myeloma

Risk of Early Mortality in Patients With Newly Diagnosed Multiple Myeloma

The overall survival of patients with multiple myeloma (MM) has been improved greatly over the last 2 decades with the broader use of novel drugs and autologous tandem transplantation. However, more than one tenth of myeloma patients still die shortly after diagnosis. We therefore aim to investigate the risk factors of early mortality (death within 60 days after diagnosis) in patients with MM. We included in this study 451 consecutive patients with MM, newly diagnosed at an Asian tertiary medical center between January 1, 2002 and April 30, 2015. A total of 57 subjects who experienced early mortality were identified. Risk factors for early mortality in myeloma patients were collected and analyzed. Early mortality occurred in 57 (12.6%) of the myeloma patients. In the multivariate analysis, being male (adjusted OR 2.93, 95% CI 1.17-7.31), serum albumin < 3.5  g/dL (adjusted OR 2.71, 95% CI 1.09-6.74), primary plasma cell leukemia (adjusted OR 17.61, 95% CI 1.01-306.05), serum albumin (adjusted OR 2.70, 95% CI 1.15-6.38), corrected serum calcium ≥ 12  mg/dL (adjusted OR 2.94, 95% CI 1.21-7.14), and LDH ≥ 250  U/L (adjusted OR 3.07, 95% CI 1.50-6.27) were identified as independent risk factors of early mortality. Pneumonia with other infections contributed most to early mortality (n = 36, 65%), followed by renal failure and cardiac failure. The early mortality rate is high (12.6%) in patients with MM. Patients who are male and those with primary plasma cell leukemia, low serum albumin, high-corrected serum calcium, or LDH are at risk of early mortality. Nearly two thirds of the myeloma patients who experienced early mortality in our study (37 of 57, 65%) died of infection. Once a high-risk group is identified, much effort is required to target new approaches for prevention, early detection, and treatment of infections.

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.

Zoledronic acid in the management of bone disease as a consequence of multiple myeloma: a review

BACKGROUND

Multiple myeloma (MM) is a haematological cancer associated with organ damage, essentially bone damage. MM continues to be considered an incurable disease and requires significant therapeutic resources.

AIM

This manuscript presents a literature review of the utility of zoledronic acid (zoledronate) in the management of bone disease in MM.

DISCUSSION

The clinical benefit of bisphosphonates in the prevention and treatment of bone disease in MM has been demonstrated in the last 10 years. A recent network meta-analysis has evaluated 20 randomised clinical trials with nearly 7000 patients with myeloma enrolled and confirms the role of these agents in the prevention of pain, bone fractures and other skeletal-related events (SRE) in MM. However, their role on survival remains unclear. Zoledronate has shown significant reductions in SRE compared with placebo or other agents with acceptable tolerability, and recent studies have shown antitumoural effects for this agent, with a marginal survival benefit demonstrated in MM.

CONCLUSIONS

Zoledronate prevents SRE in MM and presents a marginal survival benefit that deserves further investigation in controlled studies. Current clinical guidelines should be followed regarding the appropriate use of zoledronate in MM, to enhance its effects and to minimise its potential toxicity.

Targeting bone as a therapy for myeloma

Myeloma bone disease (BD) not only impairs quality of life, but is also associated with impaired survival. Studies of the biology underlying BD support the notion that the increased osteoclastogenesis and suppressed osteoblastogenesis, is both a consequence and a necessity for tumour growth and clonal expansion. Survival and expansion of the myeloma clone is dependent on its interactions with bone elements, thus targeting these interactions should have antimyeloma activities. Indeed both experimental and clinical findings indicate that bone-targeted therapies not only improve BD, but also create an inhospitable environment for myeloma cell growth and survival, favouring improved clinical outcome. This review summarizes recent progress in our understandings of the biology of myeloma BD, highlighting the role of osteoclasts and osteoblasts in this process and how they can be targeted therapeutically. Unravelling the mechanisms underlying myeloma-bone interactions will facilitate the development of novel therapeutic agents to treat BD, which as a consequence are likely to improve the clinical outcome of myeloma patients.

Consensus on the utility of bone markers in the malignant bone disease setting

Biochemical markers of bone turnover provide insight into ongoing rates of skeletal metabolism and tumor-bone interactions in patients with malignant bone disease. This article reviews the available recent evidence assessing the potential of bone markers for detecting and monitoring malignant bone lesions in patients with advanced cancers, and for assessing overall skeletal health and response to antiresorptive therapies in patients at all stages of cancer progression. Most data thus far are for urinary N-terminal cross-linked telopeptide of type I collagen (NTX) in predicting risks of skeletal morbidity and death and monitoring response to zoledronic acid in patients with bone metastases. Ongoing studies are evaluating such correlations for other markers and therapies. Emerging evidence suggests that bone markers may help identify patients at high risk for bone metastasis or bone lesion progression, thereby allowing improved follow-up. Results from ongoing clinical trials evaluating such potential applications of bone markers are awaited.

Serum C-telopeptide levels predict the incidence of skeletal-related events in cancer patients with secondary bone metastases

INTRODUCTION

We evaluated serum C-telopeptides (CTX) to see whether they may be useful as predictive markers for disease progression in cancer patients with bone metastases who are being treated with zoledronic acid (ZA).

PATIENTS AND METHODS

This was a prospective, nonrandomised study in which 26 patients with solid tumours and confirmed bone metastases were treated with ZA (4 mg every 3-4 weeks) for 24 months or until a skeletal-related event (SRE) was observed. Serum CTX levels were determined at baseline and 6, 12, 18 and 24 months after study initiation. SRE were evaluated using bone scintigraphy.

RESULTS

Study participants had prostate (50%), breast (31%), lung (11%) or bladder (8%) tumours. Mean age was 69 (range 52-84) years, and 65% men. At baseline, overall mean CTX levels were 562.47 ± 305.17 pg/dl. Patients who showed disease progression during the study period showed significantly higher CTX levels at baseline and after 18 months of ZA treatment than patients who did not progress (p = 0.040 and p = 0.006, respectively). Patients with ≥ 5 bone metastases at diagnosis had significantly higher CTX levels after 18 months of ZA treatment than patients with < 5 bone metastasis (p = 0.001). Similarly, at 12 and 18 months, patients without SRE had significantly lower CTX levels than patients in whom a SRE was observed (p = 0.005 and p = 0.001, respectively).

CONCLUSIONS

Changes in serum CTX levels seem to predict the potential for tumour control and the likelihood of developing an SRE in a sample of patients with solid tumours and bone metastases treated with ZA.

Transcriptional regulation of inducible nitric oxide synthase gene therapy: targeting early stage and advanced prostate cancer

BACKGROUND

Using the tumour type specific human osteocalcin (hOC) promoter, we have previously reported strong promoter activation in hormone independent prostate cancer cells in vitro. In the present study, we present a comparative study of the tissue specific promoter prostate specific membrane antigen (PSMA), and the tumour-type specific hOC promoter driving the inducible nitric oxide synthase (iNOS) transgene using both in vitro and in vivo models.

METHODS

In vitro cytotoxicity was assessed by clonogenic assay. Quantification of nitric oxide expression was determined by the Griess test. In vivo anti-tumour efficacy was determined by tumour growth delay following direct intra-tumoural injection of the constructs into PC3 xenografts. In addition, tumours were dissected post mortem and examined for morphological differences as well as changes in apoptotic protein expression.

RESULTS

PSMA/iNOS produced cytotoxicity in both androgen dependant and independent cell lines. Nitric oxide quantification confirmed that increased cytotoxicity was directly associated with nitric oxide production. Tumour growth delays were observed in all groups treated with the iNOS-expressing constructs ranging from 10.7 days for the hOC/iNOS single dose treatment group to a maximum of 52.2 days for the hOC/iNOS multiple dose group. Intra-tumoural assessment of iNOS and cleaved poly (ADP-ribose) polymerase protein expression demonstrated a significant up-regulation of both proteins, indicating cytotoxicity mediated through the intrinsic apoptotic pathway.

CONCLUSIONS

Highly significant tumour growth delay coupled with no detrimental side-effects were observed following treatment with the PSMA/iNOS and hOC/iNOS constructs. We consider that these findings provide a basis for the development of systemically delivered PSMA/iNOS or hOC/iNOS targeting early stage and advanced prostate cancer.

First-line treatment with zoledronic acid as compared with clodronic acid in multiple myeloma (MRC Myeloma IX): a randomised controlled trial

BACKGROUND

Bisphosphonates reduce the risk of skeletal events in patients with malignant bone disease, and zoledronic acid has shown potential anticancer effects in preclinical and clinical studies. We aimed to establish whether bisphosphonates can affect clinical outcomes in patients with multiple myeloma.

METHODS

Patients of age 18 years or older with newly diagnosed multiple myeloma were enrolled from 120 centres in the UK. Computer-generated randomisation sequence was used to allocate patients equally, via an automated telephone service, to receive 4 mg zoledronic acid as an infusion every 3-4 weeks or 1600 mg oral clodronic acid daily. Patients also received intensive or non-intensive induction chemotherapy. No investigators, staff, or patients were masked to treatment allocation, and bisphosphonate and maintenance therapy continued at least until disease progression. The primary endpoints were overall survival, progression-free survival, and overall response rate. We assessed between-group differences with Cox proportional hazards models for progression-free survival and overall survival, and with logistic regression models for overall response rate. Analysis was by intention to treat. This trial is registered, number ISRCTN68454111.

FINDINGS

1970 patients were enrolled between May, 2003, and November, 2007, of whom 1960 were eligible for intention-to-treat analysis: 981 in the zoledronic acid group (555 on intensive chemotherapy, 426 on non-intensive chemotherapy); and 979 on clodronic acid (556 on intensive chemotherapy, 423 on non-intensive chemotherapy). The treatment cutoff was Oct 5, 2009, with patients receiving bisphosphonates for a median of 350 days (IQR 137-632) before disease progression, with a median of 3·7 years' follow-up (IQR 2·9-4·7). Zoledronic acid reduced mortality by 16% (95% CI 4-26) versus clodronic acid (hazard ratio [HR] 0·84, 95% CI 0·74-0·96; p=0·0118), and extended median overall survival by 5·5 months (50·0 months, IQR 21·0 to not reached vs 44·5 months, IQR 16·5 to not reached; p=0·04). Zoledronic acid also significantly improved progression-free survival by 12% (95% CI 2-20) versus clodronic acid (HR 0·88, 95% CI 0·80-0·98; p=0·0179), and increased median progression-free survival by 2·0 months (19·5 months, IQR 9·0-38·0 vs 17·5 months, IQR 8·5-34·0; p=0·07). Rates of complete, very good partial, or partial response did not differ significantly between the zoledronic acid and clodronic acid groups for patients receiving intensive induction chemotherapy (432 patients [78%] vs 422 [76%]; p=0·43) or non-intensive induction chemotherapy (215 [50%] vs 195 [46%]; p=0·18). Both bisphosphonates were generally well tolerated, with similar occurrence of acute renal failure and treatment-emergent serious adverse events, but zoledronic acid was associated with higher rates of confirmed osteonecrosis of the jaw (35 [4%]) than was clodronic acid (3 [<1%]).

INTERPRETATION

Consistent with the potential anticancer activity of zoledronic acid, overall survival improved independently of prevention of skeletal-related events, showing that zoledronic acid has treatment benefits beyond bone health. These findings support immediate treatment with zoledronic acid in patients with newly diagnosed multiple myeloma, not only for prevention of skeletal-related events, but also for potential antimyeloma benefits.

FUNDING

Medical Research Council (London, UK), with unrestricted educational grants from Novartis, Schering Health Care, Chugai, Pharmion, Celgene, and Ortho Biotech.

First-line treatment with bortezomib rapidly stimulates both osteoblast activity and bone matrix deposition in patients with multiple myeloma, and stimulates osteoblast proliferation and differentiation in vitro

OBJECTIVES

The aim of the study was to investigate the effect of bortezomib on osteoblast proliferation and differentiation, as well as on bone matrix deposition for the first time in bisphosphonate-naïve, previously untreated patients with myeloma.

METHODS

Twenty newly diagnosed patients received four cycles of bortezomib treatment, initially as monotherapy and then combined with a glucocorticoid from cycle two to four. Bone remodeling markers were monitored closely during treatment. Furthermore, the effects of bortezomib and a glucocorticoid on immature and mature osteoblasts were also studied in vitro.

RESULTS

Treatment with bortezomib caused a significant increase in bone-specific alkaline phosphatase and pro-collagen type I N-terminal propeptide, a novel bone formation marker. The addition of a glucocorticoid resulted in a transient decrease in collagen deposition. In vitro bortezomib induced osteoblast proliferation and differentiation. Differentiation but not proliferation was inhibited by glucocorticoid treatment.

CONCLUSIONS

Bortezomib used as first-line treatment significantly increased collagen deposition in patients with multiple myeloma and osteolytic lesions, but the addition of a glucocorticoid to the treatment transiently inhibited the positive effect of bortezomib, suggesting that bortezomib may result in better healing of osteolytic lesions when used without glucocorticoids in patients that have obtained remission with a previous therapy. The potential bone-healing properties of single-agent bortezomib are currently being explored in a clinical study in patients who have undergone high-dose therapy and autologous stem cell transplantation.

Multiple myeloma: changes in serum C-terminal telopeptide of collagen type I and bone-specific alkaline phosphatase can be used in daily practice to detect imminent osteolysis

Objective: Monitoring of bone disease in multiple myeloma is becoming increasingly important because bone-protecting treatment with bisphosphonate is becoming restricted after the awareness of osteonecrosis of the jaw. Despite the potential of biochemical markers of bone remodeling to monitor dynamic bone turnover, they are not used in everyday practice. Here, we investigate their usefulness to detect imminent progressive osteolysis in relapsing patients with multiple myeloma. Methods: In an unselected cohort of 93 patients, we measured the bone resorption markers C-terminal telopeptide of collagen type I (CTX-I), C-terminal cross-linked telopeptide of type-I collagen generated by MMPs (ICTP), N-terminal cross-linked telopeptide of type-I collagen (NTX-I), and the bone formation marker bone-specific alkaline phosphatase (bALP) monthly for 2 yr. Retrospectively, we identified 40 cases where patients had progressive disease. We investigated how the bone markers developed prior to disease progression. Results: We observed that CTX-I and bALP changed significantly before progressive disease were recognized. More interestingly, these changes differed depending on whether concurrent progressive osteolysis was present. In patients with progressive osteolysis, there was a large increase in bone resorption which was not compensated by increased bone formation. In contrasts, patients with stable bone disease had only a slight increase in bone resorption which was compensated by concurrent increased bone formation. By calculating a patient-specific CTX-I/bALP ratio, we quantified the risk a patient experiences if the ratio increases. Conclusion: By analyzing patient-specific changes in the ratio of CTX-I/bALP, we might tailor treatment with bone-protecting agents in the individual patient.

Preserving functional independence in elderly patients with cancer-associated bone disease: the role of zoledronic acid

Increases in life expectancy in the developed world will inevitably lead to larger numbers of elderly patients with cancer-associated (malignant) bone disease. Most elderly patients with metastatic cancer also suffer from numerous comorbidities. The management of bone health in this setting requires special consideration. This article centers on malignant bone disease in the elderly and the role of bisphosphonates in geriatric oncology. The challenges involved in the treatment of older patients with bone metastases are described, and the potential utility of bisphosphonates, such as zoledronic acid, is discussed. Moreover, recent data from several large clinical trials suggest that zoledronic acid provides additional benefits, including antitumor effects that may extend beyond the preservation of bone health and prevention of skeletal-related events.

Effect of pathologic fractures on survival in multiple myeloma patients: a case control study

BACKGROUND

Multiple Myeloma (MM) is a B cell neoplasm characterized by the clonal proliferation of plasma cells. Skeletal complications are found in up to 80% of myeloma patients at presentation and are major cause of morbidity.

METHODS

49 patients were enrolled with MM admitted to Black Sea Technical University Hospital between 2002-2005. Pathologic fractures (PFs) were determined and the patients with or without PF were followed up minimum 3 years for survival analysis.

RESULTS

PF was observed in 24 patients (49%) and not observed in 25 patients (51%). The risk of death was increased in the patients with PF compared with patients who had no fractures. While overall survival was 17.6 months in the patients with PFs, it was 57.3 months in the patients with no PFs.

CONCLUSION

These findings suggest that PFs may induce reduced survival and increased mortality in the MM patients, however, larger sample size is essential to draw clearer conclusions added to these data.

BGLAP is expressed in pancreatic cancer cells and increases their growth and invasion

Background

Bone gamma-carboxyglutamate protein (BGLAP; osteocalcin) is a small, highly conserved molecule first identified in the mineralized matrix of bone. It has been implicated in the pathophysiology of various malignancies. In this study, we analyzed the expression and role of BGLAP in the normal human pancreas, chronic pancreatitis (CP), and pancreatic ductal adenocarcinoma (PDAC) using quantitative RT-PCR, immunohistochemistry, immunocytochemistry and enzyme immunoassays, as well as cell proliferation and invasion assays. Gene silencing was carried out using specific siRNA molecules.

Results

Compared to the normal pancreas, BGLAP mRNA and protein levels were not significantly different in CP and PDAC tissues. BGLAP was faintly present in the cytoplasm of normal acinar cells but was strongly expressed in the cytoplasm and nuclei of tubular complexes and PanIN lesions of CP and PDAC tissues. Furthermore, BGLAP expression was found in the cancer cells in PDAC tissues as well as in 4 cultured pancreatic cancer cell lines. TNFalpha reduced BGLAP mRNA and protein expression levels in pancreatic cancer cell lines. In addition, BGLAP silencing led to reduction of both cell growth and invasion in those cells.

Conclusion

BGLAP is expressed in pancreatic cancer cells, where it potentially increases pancreatic cancer cell growth and invasion through autocrine and/or paracrine mechanisms.