Bisphosphonates inhibit phosphorylation of signal transducer and activator of transcription 3 and expression of suppressor of cytokine signaling 3: implications for their effects on innate immune function and osteoclastogenesis

Management of bone metastasis with zoledronic acid: A systematic review and Bayesian network meta-analysis

Background

While considered the mainstay of treatment for specific bone metastases, ZA is used predominantly to treat osteolytic lesions. The purpose of this network meta-analysis is to compare ZA to other treatment options in its ability to improve specific clinical outcomes in patients with bone metastases secondary to any primary tumor.

Methods

PubMed, Embase and Web of Science were systematically searched from inception to May 5th, 2022. Keywords used were solid tumor, lung neoplasm, kidney neoplasm, breast neoplasm, prostate neoplasm, ZA and bone metastasis. Every randomized controlled trial and non-randomized quasi-experimental study of systemic ZA administration for patients with bone metastases and any comparator were included. A Bayesian network meta-analysis was done on the primary outcomes including number of SREs, time to developing a first on-study SRE, overall survival, and disease progression-free survival. Secondary outcome was pain at 3, 6 and 12 months after treatment.

Results

Our search yielded 3861 titles with 27 meeting inclusion criteria. For the number of SRE, ZA in combination with chemotherapy or hormone therapy was statistically superior to placebo (OR 0.079; 95 % CrI: 0.022-0.27). For the time to the first on study SRE, the relative effectiveness of ZA 4 mg was statistically superior to placebo (HR 0.58; 95 % CrI:0.48-0.77). At 3 and 6 months, ZA 4 mg was significantly superior to placebo for reducing pain with a SMD of -0.85 (95 % CrI:-1.6, -0.0025) and -2.6 (95 % CrI:-4.7, -0.52) respectively.

Conclusions

This systematic review shows the benefits of ZA in decreasing the incidence of SREs, increasing the time to the first on-study SRE, and reducing the pain level at 3 and 6 months.

Medication-Related Osteonecrosis of the Jaws

Medication-related osteonecrosis of the jaw is an oral complication in cancer patients being treated with either antiresorptive or antiangiogenic drugs. The first reports of MRONJ were published in 2003. Hundreds of manuscripts have been published in the medical and dental literature describing the complication, clinical and radiographic signs and symptoms, possible pathophysiology, and management. Despite this extensive literature, the pathobiological mechanisms by which medication-related osteonecrosis of the jaw develops have not yet been fully delineated. The aim of this manuscript is to present current knowledge about the complication ragarding to the definition, known risk factors, and clinical management recommendations. Based on this current state of the science, we also propose research directions that have potential to enhance the management of future oncology patients who are receiving these agents.

Low-dose zoledronate for the treatment of bone metastasis secondary to prostate cancer

Background

Bisphosphonates (BPs) including zoledronate (zol) have become standard care for bone metastases as they effectively inhibit tumor-induced osteolysis and associated pain. Several studies have also suggested that zol has direct anti-tumor activity. Systemic administration at high doses is the current approach to deliver zol, yet it has been associated with debilitating side effects. Local therapeutic delivery offers the ability to administer much lower total dosage, while at the same time maintaining sustained high-local drug concentration directly at the target treatment site. Here, we aimed to assess effects of lower doses of zol on bone metastases over a longer time.

Methods

Prostate cancer cell line LAPC4 and prostate-induced bone metastasis cells were treated with zol at 1, 3 and 10 µM for 7 days. Following treatment, cell proliferation was assessed using Almarblue^®, Vybrant MTT^®, and Live/Dead^® viability/cytotoxicity assays. Additionally, cell migration and invasion were carried out using Falcon™ cell culture inserts and Cultrex^® 3D spheroid cell invasion assays respectively.

Results

We show that treatment with 3–10 µM zol over 7-days significantly decreased cell proliferation in both the prostate cancer cell line LAPC4 and cells from spine metastases secondary to prostate cancer. Using the same low-dose and longer time course for treatment, we demonstrate that 10 µM zol also significantly inhibits tumor cell migration and 3D-cell growth/invasion.

Conclusions

This project harnesses the potential of using zol at low doses for longer treatment periods, which may be a viable treatment modality when coupled with biomaterials or biodevices for local delivery.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0745-x) contains supplementary material, which is available to authorized users.

Bisphosphonate-Generated ATP-Analogs Inhibit Cell Signaling Pathways

Bisphosphonates are a major class of drugs used to treat osteoporosis, Paget's disease, and cancer. They have been proposed to act by inhibiting one or more targets including protein prenylation, the epidermal growth factor receptor, or the adenine nucleotide translocase. Inhibition of the latter is due to formation in cells of analogs of ATP: the isopentenyl ester of ATP (ApppI) or an AppXp-type analog of ATP, such as AMP-clodronate (AppCCl2p). We screened both ApppI as well as AppCCl2p against a panel of 369 kinases finding potent inhibition of some tyrosine kinases by AppCCl2p, attributable to formation of a strong hydrogen bond between tyrosine and the terminal phosphonate. We then synthesized bisphosphonate preprodrugs that are converted in cells to other ATP-analogs, finding low nM kinase inhibitors that inhibited cell signaling pathways. These results help clarify our understanding of the mechanisms of action of bisphosphonates, potentially opening up new routes to the development of bone resorption, anticancer, and anti-inflammatory drug leads.

Zoledronate as effective treatment for minimal trauma fractures in a child with STAT3 deficiency and osteonecrosis of the hip

Signal transducer and activator of transcription 3 (STAT3) deficiency is a primary immunodeficiency characterized by eczema, complicated recurrent infections, elevated serum immunoglobulin E (IgE), osteopenia, and minimal trauma fractures. Zoledronic acid (ZA) is a long-acting bisphosphonate that has been successfully used in children with secondary osteoporosis and osteogenesis imperfecta. We describe the case of a 7-year-old male with STAT3 deficiency and minimal trauma fractures, who also developed osteonecrosis of the hip. He responded well to intravenous ZA every 6 months for 18 months. Three years later, he walks independently and unaided, and has not suffered any other fractures. Although more studies are needed, ZA might help reduce minimal trauma fractures in patients with STAT3 deficiency.

Zoledronic acid increases the antitumor effect of gefitinib treatment for non-small cell lung cancer with EGFR mutations

Non-small cell lung cancer (NSCLC) patients with epithelial growth factor receptor (EGFR) mutations and bone metastases are often concurrently administered tyrosine kinase inhibitors (TKIs) and bisphosphonates. Yet, the effects and mechanisms of these agents are unclear. In the present study, we aimed to ascertain whether zoledronic acid (ZA) increases the antitumor effects of gefitinib treatment on NSCLC with EGFR mutations and the related mechanisms of action. The effects of ZA and gefitinib on NSCLC tumor cells with EGFR mutations (HCC827, HCC827 GR and H1975) in regards to proliferation, apoptosis, cell cycle and signaling pathways were detected. ZA increased the antitumor effects of gefitinib on NSCLC with EGFR activating mutations and TKI resistance in vitro. Gefitinib caused cell cycle arrest in the G0/G1 phase, ZA induced S phase accumulation and the effect of the combined treatment was neutralization. Combined treatment obviously inhibited STAT3 and/or p‑STAT3 protein expression compared with treatment with each single drug in vitro and in vivo, and it also significantly inhibited TKI resistance NSCLC tumor growth in vivo. In conclusion, ZA increased the antitumor effects of gefitinib on NSCLC with EGFR activating mutations and TKI resistance by regulating the cell cycle, inducing caspase-3 expression and inhibiting STAT3 expression.

Zoledronic acid enhances lipopolysaccharide-stimulated proinflammatory reactions through controlled expression of SOCS1 in macrophages

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a serious side effect of nitrogen-containing bisphosphonate (NBP) use. Many studies have shown that BRONJ is limited to the jawbone and does not occur in the other bones. We hypothesized that BRONJ is related to local bacterial iections and involves the innate immune system. To examine the relationship between BRONJ and innate immunity, we examined the effects of NBPs on macrophages, one of the important cell types in innate immunity. The expression of toll-like receptor-4 (TLR4) in cells after pretreatment with zoledronic acid (ZOL) did not considerably differ from that in untreated control cells. However, cytokine levels and nitric oxide (NO) production increased after pretreatment with ZOL. Furthermore, ZOL induced NF-κB activation by enhancing IκB-α degradation. Lipopolysaccharide (LPS)-induced apoptosis also increased after pretreatment with ZOL. This effect was mediated by a reduction of suppressor of cytokine signaling-1 (SOCS1), which is a negative regulator of myeloid differentiation primary response gene 88 (MyD 88)-dependent signaling. These results suggest that ZOL induced excessive innate immune response and proinflammatory cytokine production and that these processes may be involved in the bone destruction observed in BRONJ.

Activated monocytes augment TRAIL-mediated cytotoxicity by human NK cells through release of IFN-γ

Natural killer (NK) cells are innate lymphocytes that are able to directly kill tumor cells through different mechanisms including ligation of TNF-related apoptosis-inducing ligand (TRAIL) receptors. Zoledronic acid (ZA) is a bisphosphonate known to upregulate the expression of TRAIL on human γδ T cells. Here, we investigated whether exposure to ZA would upregulate TRAIL expression on human NK cells and augment their cytotoxicity against tumor cells. When cocultured with monocytes, treatment with ZA and IL-2 resulted in a significant upregulation of TRAIL expression on human NK cells (p = 0.002). Consequently, ZA-primed NK cells were significantly more cytotoxic against TRAIL sensitive tumor cells (p < 0.0001). In the presence of ZA and IL-2, monocytes produced high levels of IFN-γ; when cultured in the presence of neutralizing antibodies to IFN-γ, TRAIL expression and TRAIL-mediated cytotoxicity of NK cells were significantly reduced. Furthermore, in tumor-bearing SCID/Beige mice, a significant delayed tumor progression and prolonged survival was observed after infusion of ZA-primed NK cells compared with that observed in mice infused with unprimed NK cells. These findings represent a novel approach to potentiate TRAIL-mediated apoptosis by adoptively infused NK cells that could improve the outcome in patients with cancer.

Intravenous bisphosphonate-related osteonecrosis of the jaw: long-term follow-up of 109 patients

OBJECTIVE

We report long-term follow-up of patients with intravenous bisphosphonate-related osteonecrosis of the jaw (BRONJ).

STUDY DESIGN

Medical and dental histories, including type and duration of bisphosphonate treatment and comorbidities, were analyzed and compared with clinical course of 109 patients with BRONJ at Memorial Sloan-Kettering Cancer Center Dental Service.

RESULTS

Median onset of BRONJ in months was 21 (zoledronic acid), 30 (pamidronate), and 36 (pamidronate plus zoledronic acid), with a significant difference between the pamidronate plus zoledronic acid and zoledronic acid groups (P = .01; Kruskal-Wallis). The median number of doses for BRONJ onset was significantly less with zoledronic acid (n = 18) than pamidronte plus zoledronic acid (n = 36; P = .001), but not pamidronate alone (n = 29). An association between diabetes (P = .05), decayed-missing-filled teeth (P = .02), and smoking (P = .03) and progression of BRONJ was identified through χ(2) test.

CONCLUSIONS

This long-term follow-up of BRONJ cases enhances the literature and contributes to the knowledge of BRONJ clinical course.

Zoledronic acid inhibits macrophage SOCS3 expression and enhances cytokine production

Suppressor of cytokine signaling-3 (SOCS3) has multiple functions including inhibition of Janus kinase (Jak) activity, regulation of protein degradation, and suppression of cytokine signaling. SOCS3 modulates macrophage response to cytokines such as IL-6 and leptin that are systemically induced in obesity. Obesity is a suspected risk factor for SOCS3-related pathology such as rheumatoid arthritis and Crohn's disease as well as zoledronic acid (ZA)-induced osteonecrosis of the jaw (ONJ). Thus, understanding the ability of bisphosphonates to modulate SOCS3 is necessary to qualify their contribution to these disorders. ONJ occurs in up to 10% of patients using intravenous bisphosphonates and has an unknown pathogenesis that may be linked to decreased bone turnover, altered vascularity, bacterial invasion, and compromised wound healing. Given the increased risk of ONJ with obesity and importance of macrophages in wound healing, we hypothesized that amino-bisphosphonates could contribute to the pathogenesis of ONJ by regulating macrophage responses to cytokines such as leptin and IL-6. We report that ZA is a novel inhibitor of SOCS3 in primary macrophages and human ONJ biopsy specimens. Inhibition of SOCS3 by ZA resulted in significant increases in IL-6 production. SOCS3 transcription is regulated by nuclear accumulation of phosphorylated-Stat3 (P-Stat3). We found that ZA decreased phosphorylation of Stat3 in a mevalonate-pathway dependent manner. However, restoration of P-Stat3 was not sufficient to correct SOCS3 inhibition. We propose that disruption of macrophage SOCS3 expression by amino-bisphosphonates such as ZA may be a novel contributor to inflammatory phenotypes in obesity and the pathogenesis of ONJ.