Medication-Related Osteonecrosis of the Jaw in Cancer Patients: Result from the OneFlorida Clinical Research Consortium

Precursor Radiographic Findings in Patients With Medication-Related Osteonecrosis of the Jaw

BACKGROUND

Oral surgical treatment, such as tooth extraction, has been identified as a risk factor for the onset of medication-related osteonecrosis of the jaw (MRONJ). However, MRONJ may already be latent, and its manifestation may be triggered by extraction.

PURPOSE

The purpose of this study was to examine the association between pre-extraction imaging and MRONJ.

STUDY DESIGN, SETTING, SAMPLE

We performed a multicenter case-control analysis of patients receiving antiresorptive agents (ARAs) who underwent extraction between 2012 and 2016. We enrolled patients who had undergone tooth extraction in the setting of ARA exposure.

PREDICTOR VARIABLES

The predictor variables comprised preoperative radiographic findings associated with MRONJ stage 0. These findings included alveolar bone loss, thickening or obscuring of the periodontal ligament, and osteosclerosis involving the alveolar bone. They were coded as present or absent before tooth extraction.

MAIN OUTCOME VARIABLE

The primary outcome variable was MRONJ status coded as present or absent.

COVARIATES

Sex, age, underlying diseases necessitating the administration of ARA, the type of ARA used, corticosteroid use, extraction region, and wound closure were analyzed.

ANALYSES

Mann-Whitney U test, χ2 test, Fisher's exact test for univariate analysis, and multiple logistic regression analysis were performed. P values < .05 were significant.

RESULTS

The subjects consisted of 26 patients and 110 controls (male: 8/36, female: 18/74). The mean ages of the MRONJ group and the control group were 77.0 ± 11.9 and 63.0 ± 15.8, respectively (P value = .001). The prevalence of osteosclerosis was significantly higher in the MRONJ group than in the control group (14/72, 53.9%/29.3%, P < .01). Multivariate analysis identified osteosclerosis (odds ratio: 8.4, 95% confidence interval: 2.133.9, P < .01) as a significant independent predictor associated with the development of MRONJ after extraction.

CONCLUSION AND RELEVANCE

These findings suggest that a precursor to MRONJ is highly likely to be present in patients with osteosclerosis at the time of extraction. The majority of patients who developed MRONJ after extraction had imaging findings that suggested infection in the surrounding alveolar bone.

Erianin serves as an NFATc1 inhibitor to prevent breast cancer-induced osteoclastogenesis and bone destruction

INTRODUCTION

Breast cancer-related bone metastasis can lead to skeletal-related events (SREs), which decrease patient quality of life. Inhibition of osteoclastogenesis is a key treatment for SREs; however, the availability of clinical drugs remains limited, and all existing ones disrupt physiological bone formation, while exhibiting no effect on patient survival time.

OBJECTIVES

This study aimed to identify a novel osteoclast inhibitor for the treatment of breast cancer-induced SREs.

METHODS

The MDA-MB-231 breast cancer cell-induced bone loss model was used to investigate the therapeutic effects of erianin in vivo. Then, we evaluated the inhibitory effects of erianin on osteoclastogenesis and signalling in bone marrow-derived macrophages (BMMs) induced by conditioned medium from MDA-MB-231 breast cancer cells (231 CM) and receptor activator of nuclear factor-κB ligand (RANKL) in vitro. Next, a Cellular Thermal Shift Assay and siRNA-mediate knockdown were performed, to investigate the target of erianin during osteoclast formation. The effects of erianin on human osteoclastogenesis were evaluated using CD14+ monocytes obtained from patients with breast cancer.

RESULTS

Erianin effectively improved breast cancer cells-induced bone destruction at doses of 2 and 20 mg/kg/day in vivo, while suppressing osteoclastogenesis and the upregulation of SRC-NFATc1, INTEGRIN β3-MMP9 signals induced by 231 CM and RANKL in vitro. Furthermore, erianin interacted with NFATc1 but not SRC, and Nfatc1 knockdown eliminated the inhibitory effects of erianin on osteoclastogenesis. Notably, lower expression of NFATc1 positively correlated with longer survival in patients with cancer and a high risk of bone metastasis. We further revealed that 62.5-250 nM erianin suppresses NFATc1 and excessive osteoclastogenesis in CD14+ monocytes from patients with breast cancer.

CONCLUSION

Erianin acts as an NFATc1 inhibitor that attenuates breast cancer-induced osteoclastogenesis and bone destruction.

Highlights on the Effects of Non-Coding RNAs in the Osteonecrosis of the Jaw

Osteonecrosis of the jaw is the progressive loss and destruction of bone affecting the maxilla or mandible in patients treated with antiresorptive and antiangiogenic agents without receiving prior radiation therapy. The pathogenesis involves the inflammatory pathway of receptor activator of nuclear factor NF-kB ligand and the macrophage colony-stimulating factor, essential for osteoclast precursors survival and proliferation and acting through its receptor c-Fms. Evidence has shown the role of non-coding RNAs in the pathogenesis of osteonecrosis of the jaw and this finding might be useful in diagnosis since these small RNAs could be considered as biomarkers of apoptotic activity in bone. Interestingly, it has been proved that miR-29 and miR-31-5p, acting on specific targets such as CALCR and RhoA, promote programmed-cell death and consequently the necrosis of bone tissue. Specific long non-coding RNAs, instead, have been detected both at reduced levels in patients with multiple myeloma and osteonecrosis, and associated with suppression of osteoblast differentiation, with consequences in the progression of mandible lesions. Among non-coding genic material, circular RNAs have the capability to modify the expression of specific mRNAs responsible for the inhibition of bisphosphonates activity on osteoclastogenesis.

New insights into the role of long non-coding RNAs in osteoporosis

Osteoporosis is a common disease in elderly individuals, and osteoporosis can easily lead to bone and hip fractures that seriously endanger the health of elderly individuals. At present, the treatment of osteoporosis is mainly anti-osteoporosis drugs, but there are side effects associated with anti-osteoporosis drugs. Therefore, it is very important to develop early diagnostic indicators and new therapeutic drugs for the prevention and treatment of osteoporosis. Long noncoding RNAs (lncRNAs), noncoding RNAs longer than 200 nucleotides, can be used as diagnostic markers for osteoporosis, and lncRNAs play an important role in the progression of osteoporosis. Many studies have shown that lncRNAs can be the target of osteoporosis. Therefore, herein, the role of lncRNAs in osteoporosis is summarized, aiming to provide some information for the prevention and treatment of osteoporosis.