odanacatib and Breast-Neoplasms

It has been long recognized that skeleton represents one of the most favored metastatic sites for common cancers like breast and prostate. During the last decade the molecular mechanisms that are responsible for the development of bone metastasis have been gradually illuminated. It appears that the bone microenvironment has a pivotal role in this process. Metastatic tumor cells interact with bone triggering a cascade of molecular events that produce osteolytic and/or osteoblastic phenomena. In this review, we summarize and discuss the most significant factors and signaling pathways implicated in bone colonization. Moreover, based on the recent literature and data, we foresee the need for designing novel agents that will efficiently disrupt these interactions among cancer cells and bone microenvironment, bringing hope for more effective treatments.

Topics: Animals; beta Catenin; Biphenyl Compounds; Bone Neoplasms; Bone Remodeling; Breast Neoplasms; Cathepsin K; Chemokine CXCL12; Diphosphonates; Endothelin-1; Female; Humans; Hypoxia; Male; Neoplastic Stem Cells; Osteoblasts; Osteoclasts; Osteolysis; Parathyroid Hormone-Related Protein; Prostatic Neoplasms; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Receptors, CXCR4; Signal Transduction; Urokinase-Type Plasminogen Activator; Wnt Proteins

Cancer cells that metastasize to the skeleton are, on their own, rarely able to destroy bone. Instead, they stimulate the function of bone-degrading cells, the osteoclasts, leading to the formation of osteolytic lesions. The purpose of this review is to consider cathepsin K, a cysteine protease produced by osteoclasts, as a therapeutic target for the treatment of patients with osteolytic bone metastases.. Cathepsin K plays a key role in osteoclast-mediated bone degradation. It is also produced by cancer cells that metastasize to bone where it functions in proteolytic pathways that promote cancer cell invasion. Highly selective and potent cathepsin K inhibitors have been recently developed and shown to be useful antiresorptive agents to treat osteoporosis. Moreover, preclinical studies show that cathepsin K inhibitors reduce breast cancer-induced osteolysis and skeletal tumor burden. This reduction of skeletal tumor burden is due to the antiresorptive activity of cathepsin K inhibitors, which in turn, deprive cancer cells of bone-derived growth factors that are required for tumor growth.. Cathepsin K inhibitors are appropriate drugs to treat diseases associated with increased bone loss. However, their chronic use in treating osteoporosis may result in adverse effects because basic nitrogen-containing cathepsin K inhibitors accumulate within acidic organelles such as lysosomes, thereby inhibiting the activity of other cathepsins. These adverse effects should not, however, preclude the use of these drugs in life-threatening diseases such as bone metastasis.

Topics: Azepines; Benzamides; Biphenyl Compounds; Bone Neoplasms; Bone Remodeling; Bone Resorption; Breast Neoplasms; Cathepsin K; Cathepsins; Female; Humans; Male; Osteoclasts; Piperazines; Prostatic Neoplasms; Sulfones; Thiazoles

Metastatic bone disease (MBD) is a frequent complication in patients with breast cancer and is associated with significant morbidity. This study assessed the pharmacokinetics, efficacy, and safety of odanacatib, a selective Cat K inhibitor, in reducing markers of bone resorption in women with breast cancer and MBD.. Women with breast cancer and MBD were randomized 2:1 (double-blind) to oral odanacatib 5 mg daily for 4 weeks or intravenous (I.V.) zoledronic acid (ZA) 4 mg given once at study initiation. Plasma samples were collected for pharmacokinetic analysis. Bone resorption was assessed by measuring urinary N-telopeptide of type I collagen corrected for creatinine (uNTx; primary objective, pmol BCE/µmol creatinine). Adverse events (AEs) were monitored throughout the 4-week study and up to 14 days after last dose.. A total of 43 patients (mean age, 60 years) received odanacatib (n = 29) or ZA (n = 14); 40 patients completed 4 weeks of treatment. The mean percent change in uNTx values at week 4 was -77% (95% CI, -82 to -71; odanacatib) and -73% (95% CI, -80 to -62; ZA). Mean (standard deviation) plasma concentration of odanacatib was 511.7 (202.9) nM; the range was 63.7-844.8 nM. The most common AEs were nausea, vomiting, headache, and bone pain, which were generally not attributed to study drug.. Odanacatib suppressed uNTx similarly to ZA after 4 weeks of treatment in women with breast cancer and MBD. Odanacatib was generally safe and well tolerated. These results suggest that Cat K inhibition is a potentially important, novel therapeutic approach for treating MBD.

Topics: Adult; Biomarkers; Biphenyl Compounds; Bone Density Conservation Agents; Bone Neoplasms; Bone Resorption; Breast Neoplasms; Cathepsin K; Collagen Type I; Diphosphonates; Double-Blind Method; Female; Humans; Imidazoles; Middle Aged; Treatment Outcome; Zoledronic Acid

Approximately 90% of patients with advanced breast cancer develop bone metastases; an event that results in severe decrease of quality of life and a drastic deterioration in prognosis. Therefore, to increase the survival of breast cancer patients, the development of new therapeutic strategies to impair metastatic process and skeletal complications is critical. Previous studies on the role of cathepsin K (CTSK) in metastatic spreading led to several strategies for inhibition of this molecule such as MIV-711 (Medivir), balicatib and odanacatib (ODN) which were on trial in the past. The present study intended to assess the anti-metastatic efficacy of ODN in breast cancer cells. Human breast cancer cell lines MDA-MB-231 were treated with different concentrations of ODN and performed invasion, adhesion and migration assays and, RT-PCR and western blot to evaluate the effect of ODN on the metastatic potential of breast cancer cells. ODN markedly decreased wound healing cell migration, invasion and adhesion at a dose dependent manner. ODN inhibits cell invasion by decreasing the matrix metalloproteinase (MMP-9) with the upregulation of TIMP-1 expression. ODN effectively inhibited the phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal Kinase (JNK), and blocked the expression of β-integrins and FAK proteins. ODN also significantly inhibited PI3K downstream targets Rac1, Cdc42, paxillin and Src which are critical for cell adhesion, migration and cytoskeletal reorganization. ODN exerts anti-metastatic action through inhibition of signaling pathway for MMP-9, PI3K and MAPK. This indicates potential therapeutic effects of ODN in the treatment of metastatic breast cancer.

Topics: Benzamides; Biphenyl Compounds; Breast Neoplasms; Cathepsin K; Cell Adhesion; Cell Line, Tumor; Cell Movement; Cell Proliferation; Female; Gene Expression Regulation, Neoplastic; Humans; Matrix Metalloproteinase 9; Neoplasm Invasiveness; Neoplasm Metastasis; Neoplasm Proteins; Organic Chemicals; Phosphatidylinositol 3-Kinases; Piperazines; Tissue Inhibitor of Metalloproteinase-1

Breast cancer (BC) produces bone resorptive cytokines and growth factors that accelerate the development of osteoclasts (OCs), leading to osteolytic bone metastases. In the Long-term Odanacatib Fracture Trial (LOFT), the skeletal-metastasized breast cancer subjects who received odanacatib (ODN) had a delayed tumour progression and skeletal tumour burden as a result of anti-resorptive effects through inhibition of cathepsin K (CTSK). In this study, we explored the effect of ODN, a CTSK inhibitor, on the paracrine pro-osteoclast activity of breast cancer cells.. An immunohistochemistry study was performed to demonstrate CTSK and PTHrP expression in the samples of primary breast carcinoma. Expression of CTSK mRNA and protein was confirmed by the reverse transcription PCR and western blotting analysis in two human breast cancer cell lines, MDA-MB-231 and MCF-7 BC cell lines. Cells were incubated with sub-lethal amounts of ODN, and their conditioned supernatants were assessed for their capacity to differentiate PBMCs of healthy donors into osteoclast and its interference on bone-resorbing activities. We also measured the mRNA levels of major pro-osteoclast (pro-OC) factors in ODN-treated breast cancer cells and their secreted levels by semi-quantitative reverse transcription PCR and protein expression by immunoblotting.. Different staining intensity was observed in samples containing PTHrP and CTSK in various histological grades of breast carcinoma. A significant positive relationship was found between CTSK expression and histological grade of BC and presence or absence of distant metastasis. The present study results also indicate that ODN has no effects on OCs number, however, ODN decreases the mRNA expression of secreted pro-OC factors such as PTHrP, CXCR-4, and TNF-α. Immunoblot indicates that ODN treatment decreased the protein expression of CTSK, IL-6, and IL-1β, and thus lowered protein levels paralleled the defective phosphorylation of NF-κB. Moreover, there was a significant reduction in the level of growth factors such as IGF-1, PDGF, and TGFβ expression at transcriptional level after ODN treatment as compared to control.. ODN has shown to prevent osteolytic metastasis by interacting with the NF-κB pathway, inhibiting bone resorptive cytokines and growth factors. This effect can also be taken into account the delayed development of metastatic bone disease found in the long-term odanacatib fracture trial (LOFT) study.

Topics: Biphenyl Compounds; Breast Neoplasms; Cathepsin K; Female; Humans; Osteoclasts