Bone-targeted Therapy Research Articles

The endocrine influence on the bone microenvironment in early breast cancer.

Multiple factors influence the survival of disseminated breast tumour cells (DTCs) in bone. Whereas gene signature studies have identified genes that predict a propensity of tumours to metastasise to bone, the bone environment is key in determining the fate of these tumour cells. Breast cancer cells locate to specific niches within the bone that support their survival, regulated by host factors within the bone microenvironment including bone cells, cells of the bone micro vasculature, immune cells and the extracellular matrix. Reproductive endocrine hormones that affect bone and clinical studies across the menopausal transition have provided comprehensive understanding of the changes in the bone microenvironment during this time. Menopause is characterized by a decrease in ovarian oestradiol and inhibins, with an increase in pituitary follicle-stimulating hormone and this review will focus on the role of these three hormones in determining the fate of DTCs in bone. Both in vivo and clinical data suggest that premenopausal bone is a conducive environment for growth of breast cancer cells in bone. Adjuvant cancer treatment aims to reduce the risk of tumour recurrence by affecting DTCs. Drugs targeting the bone resorbing osteoclasts, such as bisphosphonates, have therefore been evaluated in this setting. Both preclinical and adjuvant clinical studies have shown that bisphosphonates' ability to decrease tumour growth in bone is influenced by the levels of endocrine hormones, with enhanced effects in a postmenopausal bone microenvironment. The challenge is to understand the molecular mechanisms behind this phenomenon and to evaluate if alternative adjuvant bone-targeted therapies may be effective in premenopausal women.

Prevention and management of osteonecrosis of the jaw secondary to bone-targeted therapy in patients with kidney cancer.

The aim of this revision is prevention and management of osteonecrosis of the jaw (ONJ) secondary to bone-targeted therapy in patients with kidney cancer. Patients with kidney cancer treated with zoledronate suffered from ONJ earlier compared with patients with breast cancer or multiple myeloma; among men, ONJ occurred at 24 months of zoledronic acid treatment in more than 80% of the patients and much earlier, in respect to patients with prostate cancer or multiple myeloma. Protective factors against an ONJ can be sequential prescription of different bisphosphonates and female sex. Less data are available on ONJ secondary to denosumab administration in patients with kidney cancer. Bone metastases, developing in about 30% of the patients with metastatic renal cell carcinoma, are typically osteolytic on imaging and cause significant morbidity and poor quality of life. Incidence of skeletal-related events has been reported to reach 3.38 per year in such patients. To decrease the incidence of ONJ, a maxillofacial examination must be performed in all patients before treatment with bisphosphonates, in particular in patients with metastatic renal cell carcinoma treated with sunitinib alone or in association with zoledronate. The management of ONJ consider a conservative approach.

Breast cancer and bone metastases: a call for appropriate treatment.

The aim of this study is to provide an overview of the potential barriers to uptake of bone-targeted agents for the prevention of skeletal-related events (SREs) in patients with breast cancer and bone metastases. A top-line literature review was conducted to identify trends in and barriers to initiating bone-targeted therapy in patients with metastatic breast cancer. The majority of patients with bone metastases that are secondary to breast cancer clearly benefit from treatment with a bone-targeted agent such as the RANK ligand inhibitor denosumab or the bisphosphonate zoledronic acid, because both delay the onset of SREs. Evidence suggests, however, that these agents are not being used in these patients as per European guideline recommendations. Adoption of a number of behavioral changes may help to overcome barriers to earlier initiation of treatment with bone-targeted agents in these patients. This includes raising awareness of the guidelines that are available for bone-targeted therapies, providing physician and patient education on the appropriate use of these agents, and highlighting to physicians the importance of early treatment and regular monitoring for adverse events. Earlier initiation of treatment should help to reduce the risk of SREs and thus lessen the burden that these debilitating skeletal complications place on patients and healthcare systems.

A phase 2 trial exploring the clinical and correlative effects of combining doxycycline with bone-targeted therapy in patients with metastatic breast cancer

BackgroundBone-targeting agents (BTAs), such as bisphosphonates and denosumab, have demonstrated no discernable effects on tumour response or disease free/overall survival in patients with bone metastases from breast cancer. Doxycycline is both osteotropic and has anti-cancer effects. When combined with zoledronate in animal models, doxycycline showed significantly increased inhibition of tumour burden and increased bone formation. We evaluated the effects of adding doxycycline to ongoing anti-cancer therapy in patients with metastatic breast cancer. MethodsBreast cancer patients with bone metastases and ≥3 months of BTA use, entered this single-arm study. Patients received doxycycline 100mg orally, twice a day for 12 weeks. The co-primary endpoints were; effect on validated pain scores (FACT-Bone pain and Brief Pain Inventory) and bone resorption markers (serum C-telopeptide, [sCTx]). All endpoints (pain scores, sCTx, bone-specific alkaline phosphatase, skeletal-related events, toxicity) were evaluated at baseline, 4, 8 and 12 weeks. Bone marrow was sampled at baseline and week 12 for exploratory biomarker analysis. ResultsOut of 37 enroled patients, 27 (73%) completed 12 weeks of therapy. No significant changes were seen in pain scores or bone turnover markers. Failure to complete treatment: drug toxicity (70%) and disease progression (30%). Sixteen (43%) patients had GI adverse events. ConclusionsDoxycycline 100mg twice daily for 12 weeks had no significant effects on either bone pain or bone turnover markers. Its toxicity profile in this patient population would make further evaluation challenging.

TRAPEZE: a randomised controlled trial of the clinical effectiveness and cost-effectiveness of chemotherapy with zoledronic acid, strontium-89, or both, in men with bony metastatic castration-refractory prostate cancer

Bony metastatic castration-refractory prostate cancer is associated with a poor prognosis and high morbidity. TRAPEZE was a two-by-two factorial randomised controlled trial of zoledronic acid (ZA) and strontium-89 (Sr-89), each combined with docetaxel. All have palliative benefits, are used to control bone symptoms and are used with docetaxel to prolong survival. ZA, approved on the basis of reducing skeletal-related events (SREs), is commonly combined with docetaxel in practice, although evidence of efficacy and cost-effectiveness is lacking. Sr-89, approved for controlling metastatic pain and reducing need for subsequent bone treatments, is generally palliatively used in patients unfit for chemotherapy. Phase II analysis confirmed the safety and feasibility of combining these agents. TRAPEZE aimed to determine the clinical effectiveness and cost-effectiveness of each agent. Patients were randomised to receive six cycles of docetaxel plus prednisolone: alone, with ZA, with a single Sr-89 dose after cycle 6, or with both. Primary outcomes were clinical progression-free survival (CPFS: time to pain progression, SRE or death) and cost-effectiveness. Secondary outcomes were SRE-free interval (SREFI), total SREs, overall survival (OS) and quality of life (QoL). Log-rank test and Cox regression modelling were used to determine clinical effectiveness. Cost-effectiveness was assessed from the NHS perspective and expressed as cost per additional quality-adjusted life-year (QALY). An additional analysis was carried out for ZA to reflect the availability of generic ZA. 757 randomised (median age 68.7 years; Eastern Cooperative Oncology Group scale score 0, 40%; 1, 52%; 2, 8%; prior radiotherapy, 45%); median prostate-specific antigen 143.78 ng/ml (interquartile range 50.8-353.9 ng/ml). Stratified log-rank analysis of CPFS was statistically non-significant for either agent (Sr-89, p = 0.11; ZA, p = 0.45). Cox regression analysis adjusted for stratification variables showed CPFS benefit for Sr-89 [hazard ratio (HR) 0.845, 95% confidence interval (CI) 0.72 to 0.99; p = 0.036] and confirmed no effect of ZA (p = 0.46). ZA showed a significant SREFI effect (HR 0.76; 95% CI 0.63 to 0.93; p = 0.008). Neither agent affected OS (Sr-89, p = 0.74; ZA, p = 0.91), but both increased total cost (vs. no ZA and no Sr-89, respectively); decreased post-trial therapies partly offset costs [net difference: Sr-89 £1341; proprietary ZA (Zometa(®), East Hanover, NJ, USA) £1319; generic ZA £251]. QoL was maintained in all trial arms; Sr-89 (0.08 additional QALYs) and ZA (0.03 additional QALYs) showed slight improvements. The resulting incremental cost-effectiveness ratio (ICER) for Sr-89 was £16,590, with £42,047 per QALY for Zometa and £8005 per QALY for generic ZA. Strontium-89 improved CPFS, but not OS. ZA did not improve CPFS or OS but significantly improved SREFI, mostly post progression, suggesting a role as post-chemotherapy maintenance therapy. QoL was well maintained in all treatment arms, with differing patterns of care resulting from the effects of Sr-89 on time to progression and ZA on SREFI and total SREs. The addition of Sr-89 resulted in additional cost and a small positive increase in QALYs, with an ICER below the £20,000 ceiling per QALY. The additional costs and small positive QALY changes in favour of ZA resulted in ICERs of £42,047 (Zometa) and £8005 for the generic alternative; thus, generic ZA represents a cost-effective option. Additional analyses on the basis of data from the Hospital Episode Statistics data set would allow corroborating the findings of this study. Further research into the use of ZA (and other bone-targeting therapies) with newer prostate cancer therapies would be desirable. Current Controlled Trials ISRCTN12808747. This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 53. See the NIHR Journals Library website for further project information.

Rethinking end-points for bone-targeted therapy in advanced cancer

The principal objective for any medical therapy is to improve either the duration of life and/or its quality. Metastases in bone can lead to clinically defined events termed skeletal-related events (SREs) which are a quantifiable measure of skeletal morbidity. Avoidance and/or delay of SREs have become the principal objective in trials exploring the efficacy of bone-targeted therapy in patients with skeletal metastases. Despite reductions in the frequency or rate of SRE occurrence, trials of bone-targeted therapy have failed to show any effect on either progression-free or overall survival when compared with placebo or other bone-targeting agents. Similarly, trials of bone-targeted therapy have not shown consistent effects on quality of life. The validity of SRE-based primary outcome measures in cancer clinical trials is therefore, questionable. More novel end-point selection for trials of bone-targeted therapy seems warranted. Composite measures comprising occurrence of symptomatic skeletal events and patient reported outcomes may be an effective solution and warrants further investigation.

Adjuvant Bone-Targeted Therapies for Postmenopausal Breast Cancer.

Adjuvant Bone-Targeted Therapies for Postmenopausal Breast Cancer.

Editorial comment on ‘Effects of neoadjuvant chemotherapy with or without zoledronic acid on pathological response: A meta-analysis of randomised trials’

In this issue of the European Journal of Cancer, Kroep et al. present their meta-analysis of randomised trials of adding zoledronic acid (ZOL) to neoadjuvant therapy in breast cancer [1]. In their well written paper, they have pooled the individual patient data of 750 patients from four randomised clinical trials. For some, the overall result may be disappointing: In essence, the addition of ZOL overall did not increase complete pathological remission (pCR), which is viewed as the surrogate parameter of choice in the neoadjuvant treatment of breast cancer. Interestingly, however the addition of the bisphosphonate nearly doubled pCR rates in the subgroup of postmenopausal patients, a striking parallelism to the differential menopausal effect of adjuvant bisphosphonate therapy [2]. While it may be considered unlikely that neoadjuvant ZOL will become part of routine clinical practice, this paper raises interesting scientific questions: What is the mechanism of action? And why is there an activity signal in postmenopausal patients only? In any case, the long and winding road of bone-targeted therapy in breast cancer with respect to outcome benefit is enriched with another interesting facet.

Metastatic bone disease in the era of bone-targeted therapy: clinical impact.

Advances in the diagnosis and treatment of tumors by surgery, chemotherapy, biotherapy, radiotherapy and other modalities have increased the survival of cancer patients over the last 20 years. As a consequence, bone now represents the third most common site of metastatic involvement after the lung and liver. Approximately 20-25% of patients with neoplastic disease develop clinically evident bone metastases (BMs) during the natural course of their illness, with a further 50% of such lesions being identified during autopsy. BMs are the major cause of morbidity in cancer patients because of their epidemiological and clinical impact. Pain is the most frequent symptom in about 75% of patients but other serious complications can also occur, such as pathological fractures, spinal cord compression, hypercalcemia and bone marrow suppression. These complications worsen the patient's general condition and reduce patients' mobility, facilitating the development of lung infections, skin ulcers, deep vein thrombosis, etc., and ultimately reducing prognosis and quality of life. The frequency of serious complications depends on the site and type of lesions and the treatment administered. Over the last 10 years, the introduction of bisphosphonates for the treatment of patients with BMs has led to a marked decrease in the frequency of complications, thus improving quality of life and clinical outcome. Furthermore, progress in understanding the pathophysiology of bone metastases has resulted in the development of new bone-targeted molecules such as denosumab. We therefore felt it would be useful to report on the epidemiological, clinical and economic impact of bone disease in a cancer setting.

Transformative therapy in hypophosphatasia

Hypophosphatasia (HPP) is a rare, potentially life-threatening disease characterised by hypomineralisation of bones and teeth.1 The fundamental defect is reduced functional activity of the enzyme tissue-nonspecific alkaline phosphatase (usually just...

Current Controversies in the Management of Myeloma Bone Disease.

Recent significant advances in the treatment of multiple myeloma have resulted in an improvement in median overall survival from 4.6 years, for patients diagnosed between 2001 and 2005, to 6.1 years, for those diagnosed between 2006 and 2010 (Kumar et al., 2014). However, myeloma bone lesions persist in the absence of active disease and continue to be frequent and significant causes of patient morbidity and contribute to mortality. While bisphosphonate therapy in combination with anti-myeloma therapy remains the cornerstone of skeletal disease management in myeloma, open questions regarding the optimal management of patients with myeloma bone disease remain. This article will address when to initiate and stop bone-targeted therapy in patients with monoclonal gammopathies, duration of bisphosphonate treatment in the era of more effective anti-myeloma treatment, the role of bone resorption markers in determining the dosing schedule for anti-resorptive therapy, risks and benefits of long term anti-resorptive therapy, and whether anti-resorptive therapies should be stopped to enhance the potential anabolic effects of proteasome antagonists and other anabolic agents. J. Cell. Physiol. 231: 2374-2379, 2016. © 2016 Wiley Periodicals, Inc.

Skeletal metastases and impact of anticancer and bone-targeted agents in patients with castration-resistant prostate cancer.

Incidence of bone metastases is very high in advanced prostate cancer patients. Bone metastases likely have a significant impact on functional status and quality of life, not only related to pain, but also to the relevant risk of skeletal-related events. A better understanding of mechanisms associated with bone metastatic disease secondary to prostate cancer and more specifically to the cross-talk between tumor cells and bone microenvironment in metastatic progression represented the background for the development of new effective bone-targeted therapies. Furthermore, a better knowledge of biological mechanisms driving disease progression led to significant advances in the treatment of castration-resistant prostate cancer, with the development and approval of new effective drugs. Aim of this review is to outline the physiopathology of bone metastases in prostate cancer and summarize the main results of clinical trials conducted with different drugs to control morbidity induced by skeletal metastases and bone disease progression. For each agent, therapeutic effect on bone metastases has been measured in terms of pain control and/or incidence of skeletal-related events, usually defined as a composite endpoint, including the need for local treatment (radiation therapy or surgery), spinal cord compression, pathological bone fractures. In details, data obtained with chemotherapy (mitoxantrone, docetaxel, cabazitaxel), new generation hormonal agents (abiraterone, enzalutamide), radium-223, bone-targeted agents (zoledronic acid, denosumab) and with several experimental agents (cabozantinib, dasatinib, anti-endothelin and other agents) in patients with castration-resistant prostate cancer are reviewed.

Potential Involvement of Jagged1 in Metastatic Progression of Human Breast Carcinomas.

Jagged1, the ligand of Notch, has been shown to be involved in formation of bone metastases in an experimental study. Here, clinical relevance of Jagged1 expression in tumor progression was assessed in human breast carcinomas. Jagged1 expression was evaluated by immunohistochemistry in 228 tumor tissue samples and compared to clinicopathologic parameters and patients' outcomes. Furthermore, circulating tumor cells (CTCs) from peripheral blood of 100 unmatched metastatic cancer patients with progressive disease were enriched using Ficoll density gradient centrifugation and detected by pan-keratin/Jagged1/CD45 immunofluorescent staining. Jagged1 expression was detected in 50% of 228 tumors. Jagged1 expression was correlated with higher tumor grade (P = 0.047), vascular invasion (P = 0.026), luminal B subtype (P = 0.016), overexpression of Her-2 (P = 0.001), high Ki-67 expression (P = 0.035), and aldehyde dehydrogenase 1 (ALDH1) positivity (P = 0.013). Jagged 1 expression indicated shorter disease-free survival (DFS) (P = 0.040) and metastasis-free survival (P = 0.048) in lymph node-negative breast cancer for which it was the only independent predictor of DFS (multivariate analysis, P = 0.046). Tumors characterized by the strongest Jagged1 staining intensity (7.5% of cases) correlated with lymph node positivity (P = 0.037), metastatic relapse (P = 0.049), and higher number of disseminated tumor cells in bone marrow aspirates (P = 0.041). Twenty-one unmatched metastatic breast cancer patients with progressive disease were positive for CTCs, and 85.7% of the CTCs also expressed Jagged1. The presence of Jagged1(+) CTCs was significantly associated with shorter progression-free survival in patients treated with bisphosphonates (P = 0.013). Jagged1 expression characterizes more aggressive breast carcinoma and might be involved in tumor cell dissemination, metastatic progression, and resistance to bone-targeting therapy in breast cancer patients.

Asfotase Alfa: A Review in Paediatric-Onset Hypophosphatasia.

Hypophosphatasia (HPP) is a rare inheritable disease that results from loss-of-function mutations in the ALPL gene encoding tissue-nonspecific alkaline phosphatase (TNSALP). Therapeutic options for treating the underlying pathophysiology of the disease have been lacking, with the mainstay of treatment being management of symptoms and supportive care. HPP is associated with significant morbidity and mortality in paediatric patients, with mortality rates as high as 100% in perinatal-onset HPP and 50% in infantile-onset HPP. Subcutaneous asfotase alfa (Strensiq(®)), a first-in-class bone-targeted human recombinant TNSALP replacement therapy, is approved in the EU for long-term therapy in patients with paediatric-onset HPP to treat bone manifestations of the disease. In noncomparative clinical trials in infants and children with paediatric-onset HPP, asfotase alfa rapidly improved radiographically-assessed rickets severity scores at 24weeks (primary timepoint) as reflected in improvements in bone mineralization, with these benefits sustained after more than 3years of treatment. Furthermore, patients typically experienced improvements in respiratory function, gross motor function, fine motor function, cognitive development, muscle strength (normalization) and ability to perform activities of daily living, and catch-up height-gain. In life-threatening perinatal and infantile HPP, asfotase alfa also improved overall survival. Asfotase alfa was generally well tolerated in clinical trials, with relatively few patients discontinuing treatment and most treatment-related adverse events being of mild to moderate intensity. Thus, subcutaneous asfotase alfa is a valuable emerging therapy for the treatment of bone manifestations in patients with paediatric-onset HPP.

Retrospective Audit: Does Prior Assessment by Oral And Maxillofacial Surgeons Reduce the Risk of Osteonecrosis Of the Jaw in Patients Receiving Bone-Targeted Therapies For Metastatic Cancers To the Skeleton? – Part II

Men who receive bone-targeted therapy for metastatic prostate cancer are at increased risk of osteonecrosis of the jaw (ONJ). Development of ONJ has been associated with the administration of bone-targeted therapies in association with other risk factors. ONJ can be distressing for a patient because it can cause pain, risk of jaw fracture, body image disturbance, difficultly eating, and difficulty maintaining good oral hygiene. The aim of this article is to report results of an audit of prior assessment by oral and maxillofacial surgeons (OMFS) before initiation of bone-targeted therapies and whether it may reduce the risk of ONJ in patients receiving bone-targeted therapies for advanced cancers.

Asfotase alfa: enzyme replacement for the treatment of bone disease in hypophosphatasia.

Hypophosphatasia (HPP) is a rare disease caused by loss-of-function mutations in the tissue-nonspecific alkaline phosphatase (TNAP, TNSALP) gene. HPP causes a multisystemic syndrome with a predominant bone phenotype. The clinical spectrum ranges from high lethality in early onset (<6 months) HPP to mild late-onset syndromes. HPP management so far has been only supportive. Subcutaneous asfotase alfa, a first-in-class bone-targeted human TNAP enzyme replacement therapy, is the first compound to be approved for long-term treatment of bone manifestations in pediatric-onset HPP. In noncomparative clinical trials (treatment up to 7 years), this treatment was associated with skeletal, respiratory and functional improvement in perinatal, infantile and childhood-onset HPP. Compared with age-matched historical controls, patients with life-threatening perinatal and infantile HPP treated with asfotase alfa had substantially improved bone mineralization, survival and ventilation-free survival. In childhood HPP, asfotase alfa improved growth, gross motor function, strength and agility and decreased pain. The compound was well tolerated and most adverse events were of mild to moderate intensity. To date, data and experience concerning its efficacy and safety in long-term treatment are not yet available. Further studies to evaluate risks and benefits of enzyme replacement therapy with asfotase alfa in adults are in progress and are also strongly needed.

Osteonecrosis of the Jaw In Patients Receiving Bone- Targeted Therapies: An Overview – Part I

Urologic patients receiving bone-targeted therapies are at risk of developing osteonecrosis of the jaw (ONJ). ONJ has historically been associated with bisphosphonate therapy. More recently, RANK-Ligand inhibitors (denosumab) have also been used to reduce the risk of skeletal-related events in patients who have advanced cancers with bone metastases. More than 65% of men with metastatic prostate cancer and nearly 75% of women with metastatic breast cancer are affected by bone metastases. The literature has described ONJ associated with bisphosphonate therapy as bisphosphonate-related osteonecrosis of the jaw (BRONJ). However, with evidence also linking the use of RANK-Ligand inhibitors with osteonecrosis of the jaw, we advocate use of the term "anti-bone resorption therapy-related osteonecrosis of the jaw" (ABRT-ONJ). The term "medication-related osteonecrosis of the jaw" (MRONJ) is now becoming more widespread. There is not a universally accepted definition of ABRT-ONJ, which may have hindered recognition and reporting of the condition. In Part I of this article, a review of current knowledge around the etiology of ABRT-ONJ and incidence data are provided. In Part II, we provide an audit of ONJ in a nurse consultant-led bone support clinic. In the article, we refer to zoledronic acid because this is the bisphosphonate of choice for use in men with prostate cancer in the United Kingdom.

New cancer therapies and jaw necrosis

Osteonecrosis of the jaw (ONJ) has a number of causes, the most familiar being radiation or bisphosphonate induced. Various other novel anti-neoplastic and bone-targeting therapies that can also cause jaw necrosis have recently become available. This has led to the suggested acronym MRONJ for medication-related osteonecrosis of the jaw. This article summarises the available information on these drugs and their implications for the dental surgeon.

Clinical nomogram to predict bone-only metastasis in patients with early breast carcinoma.

Background:Bone is one of the most common sites of distant metastasis in breast cancer. The purpose of this study was to combine selected clinical and pathologic variables to develop a nomogram that can predict the likelihood of bone-only metastasis (BOM) as the first site of recurrence in patients with early breast cancer.Methods:Medical records of patients with non-metastatic breast cancer were retrospectively collected. On the basis of the analysis of patient and tumour characteristics using the Cox proportional hazards regression model, a nomogram to predict BOM was constructed for a 4175-patient-training cohort. The nomogram was validated in an independent cohort of 579 patients.Results:Among 4175 patients with non-metastatic breast cancer, 314 developed subsequent BOM. Age, T classification, lymph node status, lymphovascular space invasion, and hormone receptor status were significantly and independently associated with subsequent BOM. The nomogram had a concordance index of 0.69 in the training set and 0.73 in the validation set.Conclusions:We have developed a clinical nomogram to predict subsequent BOM in patients with non-metastatic breast cancer. Selection of a patient population at high risk for BOM could facilitate research of more specific staging approaches or the selective use of bone-targeted therapy.

Bone metastases in patients with small cell lung carcinoma: Rate of development, modality of treatment, and their impact on survival.

e18559 Background: Previous data as regards the exact impact of BMs and bone-targeted therapies on the overall prognosis of patients with SCLC are extremely limited. The aim of the present study wa...