MDSCs in bone metastasis: Mechanisms and therapeutic potential.

Bone metastasis (BM) is a frequent complication associated with advanced cancer that significantly increases patient mortality. Myeloid-derived suppressor cells (MDSCs) play a pivotal role in BM progression by promoting angiogenesis, inhibiting immune responses, and inducing osteoclastogenesis. MDSCs induce immunosuppression through diverse mechanisms, including the generation of reactive oxygen species, nitric oxide, and immunosuppressive cytokines. Within the bone metastasis niche (BMN), MDSCs engage in intricate interactions with tumor, stromal, and bone cells, thereby establishing a complex regulatory network. The biological activities and functions of MDSCs are regulated by the microenvironment within BMN. Conversely, MDSCs actively contribute to microenvironmental regulation, thereby promoting BM development. A comprehensive understanding of the indispensable role played by MDSCs in BM is imperative for the development of novel therapeutic strategies. This review highlights the involvement of MDSCs in BM development, their regulatory mechanisms, and their potential as viable therapeutic targets.

Recurrent severe hypocalcemia following chemotherapy regimen changes in advanced breast cancer: two case reports.

BACKGROUND: As an oncologic emergency related to abnormalities in calcium metabolism, hypercalcemia associated with paraneoplastic syndrome and bone metastases is well known. Meanwhile, the incidence of hypocalcemia is low, except in cases associated with bone-modifying agents used for bone metastases. Hypocalcemia induced by bone-modifying agents typically occurs early after the initial administration, and its incidence can be significantly reduced by preventive administration of calcium and vitamin D3 supplements. CASE REPORT: We report two cases of recurrent severe hypocalcemia occurring during chemotherapy for metastatic breast cancer with multiple bone metastases. Case 1: A 35-year-old Japanese woman developed metastases in the bone, liver, and ovaries during postoperative endocrine therapy for invasive lobular carcinoma of the breast. She underwent chemotherapy and treatment with denosumab. She experienced recurrent episodes of severe hypocalcemia subsequent to a change in the chemotherapy regimen. Case 2: A 65-year-old Japanese woman encountered multiple bone metastases after postoperative anti-human epidermal growth factor receptor 2 therapy and during endocrine therapy for invasive ductal carcinoma of the breast. She underwent anti-human epidermal growth factor receptor 2 therapy and treatment with denosumab. She experienced recurrent severe hypocalcemia subsequent to a change in the chemotherapy regimen to letrozole + lapatinib, trastuzumab emtansine, and lapatinib + capecitabine. CONCLUSIONS: We observed two cases of recurrent severe hypocalcemia in patients with advanced breast cancer and bone metastases after modifications to their therapy regimens. These cases differed from the typical hypocalcemia induced by bone-modifying agents. It is possible that antitumor drugs affect calcium and bone metabolism associated with bone metastases. While these cases are rare, it is crucial for oncologists to be aware of hypocalcemia not only at the initiation of bone-modifying agents but also throughout the entire antitumor therapy, as hypocalcemia can lead to fatal outcomes.

Clinical effectiveness of combined whole body hyperthermia and external beam radiation therapy (EBRT) versus EBRT alone in patients with painful bony metastases: A phase III clinical trial study.

PURPOSE: To evaluate the response rate, pain relief duration, and time it took for pain to decline or resolve after radiation therapy (RT) with or without fever-range Whole Body Hyperthermia (WBH) in bony metastatic patients with mainly primary tumor of prostate and breast cancer leading to bone pain. MATERIALS & METHODS: Bony metastatic patients with pain score ≥4 on the Brief Pain Inventory (BPI) underwent RT of 30 Gy in 10 fractions in combination with WBH with nursing care under medical supervision versus RT-alone. WBH application time was 3-4 h in three fractions with at least 48-h intervals. All patients were stratified primary site, breast or prostate cancer vs others, BPI score, and exclusion criteria. The primary endpoint was complete response (CR) (BPI equal to zero with no increase of analgesics) within two months of follow-up. RESULTS: Based on this study, the RT-alone group showed the worst pain. The study was terminated after the enrollment of a total of 61 patients, 5 years after the first enrollment (April 2016 to February 2021). Finally, the CR rate in RT + WBH revealed the most significant difference with RT-alone, 47.4% versus 5.3% respectively within 2 months post-treatment (P-value <0.05). The time of complete pain relief was 10 days for RT + WBH, while the endpoint was not reached during the RT-alone arm. Pain progression or stable disease was observed in half of the patients in RT-alone group within 4 weeks after treatment. However, this score was near zero in RT + WBHT patients in two months post-treatment. CONCLUSIONS: WBH plus RT showed significant increases in pain relief and shorter response time in comparison with RT-alone for patients with bone metastatic lesions.

Epiberberine inhibits bone metastatic breast cancer-induced osteolysis.

ETHNOPHARMACOLOGICAL RELEVANCE: The anti-tumor related diseases of Coptidis Rhizoma (Huanglian) were correlated with its traditional use of removing damp-heat, clearing internal fire, and counteracting toxicity. In the recent years, Coptidis Rhizoma and its components have drawn extensive attention toward their anti-tumor related diseases. Besides, Coptidis Rhizoma is traditionally used as an anti-inflammatory herb. Epiberberine (EPI) is a significant alkaloid isolated from Coptidis Rhizoma, and exhibits multiple pharmacological activities including anti-inflammatory. However, the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis has not been demonstrated clearly. AIM OF THE STUDY: Bone metastatic breast cancer can lead to osteolysis via inflammatory factors-induced osteoclast differentiation and function. In this study, we try to analyze the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis. METHODS: To evaluate whether epiberberine could suppress bone metastatic breast cancer-induced osteolytic damage, healthy female Balb/c mice were intratibially injected with murine triple-negative breast cancer 4T1 cells. Then, we examined the inhibitory effect and underlying mechanism of epiberberine on breast cancer-induced osteoclastogenesis in vitro. Xenograft assay was used to study the effect of epiberberine on breast cancer cells in vivo. Moreover, we also studied the inhibitory effects and underlying mechanisms of epiberberine on RANKL-induced osteoclast differentiation and function in vitro. RESULTS: The results show that epiberberine displayed potential therapeutic effects on breast cancer-induced osteolytic damage. Besides, our results show that epiberberine inhibited breast cancer cells-induced osteoclast differentiation and function by inhibiting secreted inflammatory cytokines such as IL-8. Importantly, we found that epiberberine directly inhibited RANKL-induced differentiation and function of osteoclast without cytotoxicity. Mechanistically, epiberberine inhibited RANKL-induced osteoclastogensis via Akt/c-Fos signaling pathway. Furthermore, epiberberine combined with docetaxel effectively protected against bone loss induced by metastatic breast cancer cells. CONCLUSIONS: Our findings suggested that epiberberine may be a promising natural compound for treating bone metastatic breast cancer-induced osteolytic damage by inhibiting IL-8 and is worthy of further exploration in preclinical and clinical trials.

c-MET pathway in human malignancies and its targeting by natural compounds for cancer therapy.

BACKGROUND: c-MET is a receptor tyrosine kinase which is classically activated by HGF to activate its downstream signaling cascades such as MAPK, PI3K/Akt/mTOR, and STAT3. The c-MET modulates cell proliferation, epithelial-mesenchymal transition (EMT), immune response, morphogenesis, apoptosis, and angiogenesis. The c-MET has been shown to serve a prominent role in embryogenesis and early development. The c-MET pathway is deregulated in a broad range of malignancies, due to overexpression of ligands or receptors, genomic amplification, and MET mutations. The link between the deregulation of c-MET signaling and tumor progression has been well-documented. Overexpression or overactivation of c-MET is associated with dismal clinical outcomes and acquired resistance to targeted therapies. Since c-MET activation results in the triggering of oncogenic pathways, abrogating the c-MET pathway is considered to be a pivotal strategy in cancer therapeutics. Herein, an analysis of role of the c-MET pathway in human cancers and its relevance in bone metastasis and therapeutic resistance has been undertaken. Also, an attempt has been made to summarize the inhibitory activity of selected natural compounds towards c-MET signaling in cancers. METHODS: The publications related to c-MET pathway in malignancies and its natural compound modulators were obtained from databases such as PubMed, Scopus, and Google Scholar and summarized based on PRISMA guidelines. Some of the keywords used for extracting relevant literature are c-MET, natural compound inhibitors of c-MET, c-MET in liver cancer, c-MET in breast cancer, c-MET in lung cancer, c-MET in pancreatic cancer, c-MET in head and neck cancer, c-MET in bone metastasis, c-MET in therapeutic resistance, and combination of c-MET inhibitors and chemotherapeutic agents. The chemical structure of natural compounds was verified in PubChem database. RESULTS: The search yielded 3935 publications, of which 195 reference publications were used for our analysis. Clinical trials were referenced using ClinicalTrials.gov identifier. The c-MET pathway has been recognized as a prominent target to combat the growth, metastasis, and chemotherapeutic resistance in cancers. The key role of the c-MET in bone metastasis as well as therapeutic resistance has been elaborated. Also, suppressive effect of selected natural compounds on the c-MET pathway in clinical/preclinical studies has been discussed.

Osteoclast Cancer Cell Metabolic Cross-talk Confers PARP Inhibitor Resistance in Bone Metastatic Breast Cancer.

The majority of patients with late-stage breast cancer develop distal bone metastases. The bone microenvironment can affect response to therapy, and uncovering the underlying mechanisms could help identify improved strategies for treating bone metastatic breast cancer. Here, we observed that osteoclasts reduced the sensitivity of breast cancer cells to DNA damaging agents, including cisplatin and the PARP inhibitor (PARPi) olaparib. Metabolic profiling identified elevated glutamine production by osteoclasts. Glutamine supplementation enhanced the survival of breast cancer cells treated with DNA damaging agents, while blocking glutamine uptake increased sensitivity and suppressed bone metastasis. GPX4, the critical enzyme responsible for glutathione oxidation, was upregulated in cancer cells following PARPi treatment through stress-induced ATF4-dependent transcriptional programming. Increased glutamine uptake and GPX4 upregulation concertedly enhanced glutathione metabolism in cancer cells to help neutralize oxidative stress and generate PARPi resistance. Analysis of paired patient samples of primary breast tumors and bone metastases revealed significant induction of GPX4 in bone metastases. Combination therapy utilizing PARPi and zoledronate, which blocks osteoclast activity and thereby reduces the microenvironmental glutamine supply, generated a synergistic effect in reducing bone metastasis. These results identify a role for glutamine production by bone-resident cells in supporting metastatic cancer cells to overcome oxidative stress and develop resistance to DNA-damaging therapies. SIGNIFICANCE: Metabolic interaction between osteoclasts and tumor cells contributes to resistance to DNA-damaging agents, which can be blocked by combination treatment with PARP and osteoclast inhibitors to reduce bone metastatic burden.

[Osteoprotection in patients with bone metastatic castration-resistant prostate cancer (mCRPC): real-world data from Germany, presented by d-uo]. / Osteoprotektion beim ossär metastasierten kastrationsresistenten Prostatakarzinom (mCRPC): Aktuelle Daten aus Deutschland, vorgelegt von d-uo.

INTRODUCTION: Patients with bone metastasis due to prostate cancer often present allover reduced bone mineral density. Additionally, patients with bone metastatic castration-resistant prostate cancer (mCRPC) have a relevant risk for skeletal-related events (SRE). We herein present real-world data (RWD) regarding osteoprotection in mCRPC patients with bone metastasis treated by German urologists in private practice. MATERIAL AND METHODS: This is a questionnaire-based study including members of d-uo ("Deutsche Uro-Onkologen", German uro-oncologists). All patients with histologically confirmed prostate cancer seen at least once in the surveyed urology practice between July 2019 and June 2020 were included. Questions included start, type and duration of osteoprotection as well as supplementation with calcium and vitamin D. RESULTS: Between July 2019 and June 2020, a total of 3,692 patients with prostate cancer were seen at least once in 15 urology practices. There were 410 mCRPC patients (11.1%) with bone metastasis. Osteoprotection with denosumab or a bisphosphonate to prevent SRE was applied in 274/410 mCRPC patients (66.4%) with bone metastasis. In patients receiving osteoprotection, denosumab was chosen for 67.9% of patients and a bisphosphonate was chosen for 32.1%. Supplementation with calcium and vitamin D was performed in 93.4% of the patients. The median duration of treatment was 25.3 months for denosumab compared with 39.6 months for bisphosphonates. CONCLUSIONS: Patients with mCRPC with bone metastasis received osteoprotection in 2/3 of cases. Of these, 2/3 received denosumab and 1/3 received a bisphosphonate. The majority of patients were also treated with calcium and vitamin D. According to guideline recommendations regarding osteoprotection in mCRPC patients with bone metastasis, our RWD data showed some lack of guideline adherence.

Iron Polymaltose Infusion Effects on Bone Scintigraphy and Remodeling.

ABSTRACT: A 73-year-old woman with metastatic breast cancer and known widespread skeletal metastases was referred for bone scintigraphy. Delayed images acquired at 2 and 5 hours postinjection of 30 mCi (1089 MBq) 99mTc-HDP demonstrated markedly reduced bony uptake, markedly increased renal activity, and significantly increased soft tissue accumulation. By contrast, appropriate skeletal uptake of 99mTc-HDP was seen in prior bone scans. The patient had been treated for iron deficiency anemia with an infusion of 1 g of iron polymaltose approximately 22 hours before injection of 99mTc-HDP. This phenomenon may be due to transient reduced bone resorption with increased FGF23 release secondary to IV iron supplementation.

Addressing Pain Associated with Bone Metastases: Oncology Nursing Roles in a Multidisciplinary Rapid-Access Palliative Radiotherapy Clinic.

OBJECTIVES: We provide a review of external beam radiotherapy for pain associated with bone metastases, to summarize evidence associated with different radiotherapy fraction prescriptions, and outline the oncology nursing roles in a rapid-access palliative radiotherapy clinic. Additionally, we describe the clinical capacity contributed by a nurse practitioner working at full clinical scope. DATA SOURCES: Data derived from literary databases (PubMed, CINAHL); an ethics-approved, prospective data set; and clinical expertise. CONCLUSION: Nursing provides essential contributions in the treatment and holistic symptom management in patients undergoing radiation therapy for painful bone metastases. IMPLICATIONS FOR NURSING PRACTICE: The roles of nursing in radiation oncology have been poorly elucidated within the existing literature. This evaluation provided valuable insights into the contribution of oncology nursing roles in providing timely access for individuals with painful metastasis.

Bone Metastases: From Mechanisms to Treatment.

OBJECTIVES: Bone metastases are of high clinical relevance because they are a frequent complication of most types of common cancers, such as breast and prostate. The metastatic process is complex, requiring the completion of several different steps to allow successful dissemination and homing. In addition, preparation of the metastatic niche changes the constant cycle of bone matrix formation and degradation, leading to the clinical phenotypes of lytic and sclerotic lesions. We review our current knowledge on this topic and briefly explain the current treatment landscape of bone metastasis. DATA SOURCES: These include PubMed, international guidelines, and clinician experience. CONCLUSION: Bone metastases remain a clinical challenge that negatively impacts patients prognosis and quality of life. A comprehensive understanding of the complex molecular mechanisms that results in bone metastasis is the basis for successful treatment of affected patients. The disruption of bone matrix metabolism is already recognized as the prerequisite for metastasis formation, but many open questions remain that need to be addressed in future research to establish individually tailored treatment approaches. IMPLICATIONS FOR NURSING PRACTICE: Patient-centered therapy of bone metastases requires suitable pharmacological options, and importantly a holistic approach in care delivery across the multidisciplinary team. Nurses provide the cornerstone of the multidisciplinary team and provide the closest and the most frequent contact to the patient and their families to provide timely intervention. Nurses require a basic understanding of the complex physiology of metastasis to inform practice.

Expression Profiling of Selected Immune Genes and Trabecular Microarchitecture in Breast Cancer Skeletal Metastases Model: Effect of α-Tocopherol Acetate Supplementation.

Breast cancer bone metastases (BCBM) result in serious skeletal morbidity. Although there have been important advances in cancer treatment methods such as surgery and chemotherapy, the complementary treatments, such as α-tocopherol acetate (ATA), still remain of key role via complementary and/or synergistic effects. The aim of this work was to study immune response in a rat model of BCBM due to Walker 256/B cells inoculation and the effect of ATA alone. Compared to the control group (CTRL), rat injected with Walker 256/B cells (5 × 104) in the medullar cavity (W256 group) showed osteolytic damages with marked tumor osteolysis of both cancellous and trabecular bone as assessed by X-ray radiology, micro-computed tomography, and histology. Rats inoculated with Walker 256/B cells and treated with ATA (45 mg/kg BW, W256ATA group) presented marked less tumor osteolysis, less disturbance of Tb.Th and Tb.Sp associated with conversion of rods into plates, and increased structure model index and trabecular pattern factor (Tb.Pf). Elsewhere, 3D frequency distributions of Tb.Th and Tb.Sp were highly disturbed in metastatic W256 rats. Overexpression of some genes commonly associated with cancer and metastatic proliferation: COX-2, TNF-α, and pro-inflammatory interleukins 1 and 6 was outlined. ATA alleviated most of the Walker 256/B cells-induced microarchitectural changes in the target parameters without turning back to normal levels. Likewise, it alleviates the BCSM-induced overexpression of COX-2, TNF-α, IL-1, and IL-6. In silico approach showed that ATA bound these proteins with high affinities, which satisfactory explain its beneficial effects. In conclusion, BCBM is associated with bone microarchitectural disorders and an immune response characterized by an overexpression of some key role genes in cancer proliferation and invasion. ATA exerted favorable effects on trabecular bone distribution and morphology, which may involve the COX-2, TNF-α, and ILs pathways.

Targeting Bone Metastases Signaling Pathway Using Moringa oleifera Seed Nutri-miRs: A Cross Kingdom Approach.

Moringa oleifera is a medicinally important plant that has various medical and nutritional uses. Plant miRNAs are a class of non-coding endogenous small RNAs that regulate human-specific mRNA but the mechanistic actions are largely unknown. Here, in this study, we aim to explore the mechanistic action and influence of M. oleifera seed miRNAs on vital human target genes using computer based approaches. The M. oleifera seed miRNAs sequence was taken from published data and identified its human gene targets using a psRNA target analysis server. We identified 94 miRNAs that are able to significantly regulate 47 human target genes, which has enormous biological and functional importance. Out of 47 human targeted genes, 23 genes were found to be associated with PI3K-AKT, RUNX, and MAPK1/MAPK3 signaling pathway which has shown to play key roles in bone metastases during cancer progression. The M. oleifera seed miRNAs hold a strong potential for future research that might uncover the possibility of miRNA-facilitated cross-kingdom regulation and therapeutic targets for bone metastases.

Perillaldehyde inhibits bone metastasis and receptor activator of nuclear factor-κB ligand (RANKL) signaling-induced osteoclastogenesis in prostate cancer cell lines.

Perillaldehyde (PAH), one of the active ingredients of the traditional Chinese medicine (TCM) plant Perilla frutescens, is widely used and exerts crucial anti-cancer activities. The aim of current study is to illustrate the potential mechanisms of PAH-mediated regulation of bone metastasis and osteoclastogenesis in prostate cancer (PCa) cell lines. Effects of PAH on proliferation, invasion and migration of PC-3 cells were assessed with the Cell Counting Kit-8 (CCK-8) assay and Transwell assays, respectively. Effects of PAH on stem cell characteristics of PC-3 cells were evaluated by cell-matrix adhesion assay, colony formation assay, spheroid formation assay, as well as western blot . The anti-metastasis and anti-osteoclastogenesis activity of PAH in RAW264.7 cells was examined by osteoclast differentiation assay and western blot. The protein levels of CD133 and CD44 in PC-3 cells and the activity of nuclear factor kappa B (NF-κB) signaling pathway in RAW264.7 cells were measured by western blot. PAH suppressed proliferation, invasion and migration of PC-3 cells, prevented stem cell characteristics including cell-matrix adhesion, colony formation, spheroid formation as well as CD133 and CD44 expression. PAH inhibited bone metastasis and osteoclastogenesis via repressing the activation of NF-κB pathway as well as (RANKL) - and cancer cell-induced osteoclastogenesis in PCa cells. These findings suggested the potential therapeutic effects of PAH on the metastasis of patients with PCa.

The role of microscopic bone marrow examination and [123I]MIBG scintigraphy in detection of bone marrow involvement in patients with neuroblastoma.

OBJECTIVES: For the detection of bone marrow (BM) metastases in patients with neuroblastoma, microscopic BM examination and [123I]MIBG scintigraphy are advised. The aims of this study were to assess the concordance of [123I]MIBG and microscopic BM examination (aspirate and biopsy) in detecting BM involvement and to compare invasive disease in BM biopsies and aspirates, both at diagnosis and before autologous stem cell collection (ASCC). METHODS: Fifty-five patients with stage 4 or stage 4S disease were included, and 37 of them received an autologous hematopoietic stem cell transplantation (AHSCT). The concordance rate was measured and paired binary data were analysed by the McNemar test to look for a systematic difference between diagnostic tests. RESULTS: At diagnosis and before ASCC, we found acceptable concordance rates for [123I]MIBG versus microscopic BM examination (77.1% and 85.3% respectively). Discordant results were found in both directions and at both time points. The concordance rate for biopsy versus aspirate at diagnosis was 80.6%, however, before ASCC a much higher concordance rate between both microscopic examinations was found (94.1%). While none of the aspirates showed neuroblastoma cells before ASCC, two biopsies still showed tumor invasion. CONCLUSION: For patients with neuroblastoma, a [123I]MIBG scintigraphy and a microscopic examination of BM aspirate and its biopsy should be used as complementary tools in the evaluation of BM involvement, and this both at diagnosis and during treatment (before ASCC).

Clinical and biological relevance of the transcriptomic-based prostate cancer metastasis subtypes MetA-C.

To improve treatment of metastatic prostate cancer, the biology of metastases needs to be understood. We recently described three subtypes of prostate cancer bone metastases (MetA-C), based on differential gene expression. The aim of this study was to verify the clinical relevance of these subtypes and to explore their biology and relations to genetic drivers. Freshly-frozen metastasis samples were obtained as hormone-naive (n = 17), short-term castrated (n = 21), or castration-resistant (n = 65) from a total of 67 patients. Previously published sequencing data from 573 metastasis samples were also analyzed. Through transcriptome profiling and sample classification based on a set of predefined MetA-C-differentiating genes, we found that most metastases were heterogeneous for the MetA-C subtypes. Overall, MetA was the most common subtype, while MetB was significantly enriched in castration-resistant samples and in liver metastases, and consistently associated with poor prognosis. By gene set enrichment analysis, the phenotype of MetA was described by high androgen response, protein secretion and adipogenesis, MetB by high cell cycle activity and DNA repair, and MetC by epithelial-to-mesenchymal transition and inflammation. The MetB subtype demonstrated single nucleotide variants of RB transcriptional corepressor 1 (RB1) and loss of 21 genes at chromosome 13, including RB1, but provided independent prognostic value to those genetic aberrations. In conclusion, a distinct set of gene transcripts can be used to classify prostate cancer metastases into the subtypes MetA-C. The MetA-C subtypes show diverse biology, organ tropism, and prognosis. The MetA-C classification may be used independently, or in combination with genetic markers, primarily to identify MetB patients in need of complementary therapy to conventional androgen receptor-targeting treatments.

Risk Analysis of Denosumab-Induced Hypocalcemia in Bone Metastasis Treatment: Renal Dysfunction Is Not a Risk Factor for Its Incidence in a Strict Denosumab Administration Management System with Calcium/Vitamin D Supplementation.

We have reported that a strict denosumab administration management system with oral calcium/vitamin D supplementation attenuates denosumab-induced hypocalcemia in 158 cancer patients with bone metastasis. In this report, 27.8% of the patients experienced hypocalcemia, including 0.6% with grade 2. So far, the risk factors for ≥grade 2 hypocalcemia incidence have been identified in denosumab-treated cancer patients, including patients without calcium/vitamin D supplementation. Therefore, the present study aimed to reveal the factors that affect all-grade hypocalcemia incidence with calcium/vitamin D supplementation and team medical care according to the management system. A receiver operating characteristic curve analysis suggested that the cutoff of baseline serum calcium level for all-grade hypocalcemia incidence was 9.3 mg/dL. Multivariate analysis revealed that age ≥65 years (odds ratio, 95% confidence interval: 2.57, 1.11-5.95, p = 0.03), grade 1 or higher serum alkaline phosphatase elevation (3.70, 1.71-8.00, p < 0.01), an adjusted serum calcium level of less than 9.3 mg/dL (3.21. 1.25-8.24, p = 0.02) at baseline, and co-administration of cytotoxic agents (2.33, 1.06-7.11, p = 0.03) are risk factors for the incidence of all-grade hypocalcemia. However, renal dysfunction, which has been suggested to be a risk factor in previous reports, was not a factor. In conclusion, we revealed the risk factors for all-grade hypocalcemia in calcium/vitamin D supplementation and awareness, as demonstrated by the management system. Moreover, renal dysfunction was not a risk factor in our strict denosumab administration management system. Our results support the value of early detection of hypocalcemia incidence to guide the selection of an appropriate management strategy.

Melatonin Inhibits Osteoclastogenesis and Osteolytic Bone Metastasis: Implications for Osteoporosis.

Osteoblasts and osteoclasts are major cellular components in the bone microenvironment and they play a key role in the bone turnover cycle. Many risk factors interfere with this cycle and contribute to bone-wasting diseases that progressively destroy bone and markedly reduce quality of life. Melatonin (N-acetyl-5-methoxy-tryptamine) has demonstrated intriguing therapeutic potential in the bone microenvironment, with reported effects that include the regulation of bone metabolism, acceleration of osteoblastogenesis, inhibition of osteoclastogenesis and the induction of apoptosis in mature osteoclasts, as well as the suppression of osteolytic bone metastasis. This review aims to shed light on molecular and clinical evidence that points to possibilities of melatonin for the treatment of both osteoporosis and osteolytic bone metastasis. It appears that the therapeutic qualities of melatonin supplementation may enable existing antiresorptive osteoporotic drugs to treat osteolytic metastasis.

Graves disease and metastatic hormonal-active Hürthle cell thyroid cancer: A case report.

RATIONALE: A hormone-active metastatic Hürthle cell thyroid carcinoma (HCTC) and Graves disease (GD) present a therapeutic challenge and is rarely reported. PATIENT CONCERNS: We present a 64-year-old male patient, who had dyspnea and left hip pain lasting 4 months. He had clinical signs of hyperthyroidism and a tumor measuring 9 cm in diameter of the left thyroid lobe, metastatic neck lymph node and metastases in the lungs, mediastinum, and bones. DIAGNOSIS: Laboratory findings confirmed hyperthyroidism and GD. Fine-needle aspiration biopsy and cytological investigation revealed metastases of HCTC in the skull and in the 8th right rib. A CT examination showed a thyroid tumor, metastatic neck lymph node, metastases in the lungs, mediastinum and in the 8th right rib measuring 20 × 5.6 × 4.5 cm, in the left acetabulum measuring 9 × 9 × 3 cm and parietooccipitally in the skull measuring 5 × 4 × 2 cm. Histology after total thyroidectomy and resection of the 8th right rib confirmed metastatic HCTC. INTERVENTIONS: The region of the left hip had been irradiated with concomitant doxorubicin 20 mg once weekly. When hyperthyroidism was controlled with thiamazole, a total thyroidectomy was performed. Persistent T3 hyperthyroidism, most likely caused by TSH-R-stimulated T3 production in large metastasis in the 8th right rib, was eliminated by rib resection. Thereafter, the patient was treated with 3 radioactive iodine-131 (RAI) therapies (cumulative dose of 515 mCi). Unfortunately, the tumor rapidly progressed after treatment with RAI and progressed 10 months after therapy with sorafenib. OUTCOMES: Despite treatment, the disease rapidly progressed and patient died due to distant metastases. He survived for 28 months from diagnosis. LESSONS: Simultaneous hormone-active HCTC and GD is extremely rare and prognosis is dismal. Concomitant external beam radiotherapy and doxorubicin chemotherapy, followed by RAI therapy, prevented the growth of a large metastasis in the left hip in our patient. However, a large metastasis in the 8th right rib presented an unresolved problem. Treatment with rib resection and RAI did not prevent tumor recurrence. External beam radiotherapy and sorafenib treatment failed to prevent tumor growth.

Bone recurrence in early breast cancer patients: The paradox of aromatase inhibitors induced bone resorption.

BACKGROUND: Despite the increase in chances of cure for early breast cancer (EBC) patients, approximately 20-45% of them will experience a disease recurrence, particularly bone metastases in 60-80% of cases, which occur more frequently in luminal subtypes. Endocrine therapy (ET) has always been the milestone of adjuvant treatment for hormone receptor-positive EBC patients, leading to indubitable reduction of disease recurrence risk. However, adjuvant aromatase inhibitors (AIs) therapy may promote a progressive decrease in bone mineral density (BMD), which can lead to osteoporosis. The increased bone resorption associated with osteoporosis may provide fertile soil for cancer growth and accelerate the development of bone metastases. PATIENTS AND METHODS: In this single-institution cohort study, we performed a retrospective analysis of "luminal-like" EBC patients who experienced bone recurrence after a subsequent disease free interval. The aim of the study was to evaluate the median time to skeletal recurrence (TSkR). RESULTS: 143 patients experienced bone recurrence. Median TSkR was 54 months (95%CI: 45-65). Among patients who received adjuvant AIs median TSkR was 35 months (95%CI: 25-54), while among patients who did not was 61 months (95%CI: 50-80) (HR = 1.45 [95%CI: 0.97-2.17], p = 0.0644). After adjusting for TNM stage (AJCC 8th edition), adjuvant AIs treatment was significantly related to a shorter TSkR (HR = 1.60 [95%CI: 1.06-2.42], p = 0.0244). Adjuvant Tamoxifen, adjuvant AIs/Tamoxifen and no-treatment did not revealed to be associated to TSkR. CONCLUSIONS: In this cohort of EBC patients with bone recurrence, AIs treatment seems to be related to a shorter TSkR. AIs-induced bone resorption might represent the underlying mechanism.

Bone-modifying Agents (BMAs) in Breast Cancer.

Bone-modifying agents (BMAs) are mainstays in breast cancer and prevent and treat osteoporosis in early-stage disease and reduce skeletal metastases complications in advanced disease. There is some evidence to support that BMA also prevents skeletal metastases and improves overall survival. Bone loss occurs with chemotherapy-induced ovarian failure, gonadotrophin-releasing hormone (GnRH) agonists, and aromatase inhibitors. In some women, the bone loss will be of sufficient magnitude to increase the risks of osteoporosis or fractures. Recommended steps in osteoporosis prevention or treatment include risk factor assessment, taking adequate amounts of calcium and vitamin D3, and periodic evaluations with dual-energy x-ray absorptiometry scanning. If clinically indicated by the T-scores and fracture-risk prediction algorithms treat with oral, IV bisphosphonates or subcutaneous denosumab (DEN). Zoledronic acid (ZA) or DEN reduces skeletal metastases complications, including pathological fracture, spinal cord compression, or the necessity for radiation or surgery to bone. Also, both of these drugs have the side-effect of osteonecrosis at a similar incidence. Monthly administration of ZA or DEN is standard, but several recent randomized trials show noninferiority between ZA monthly and every 3-month ZA. Every 3-month ZA is a new standard of care. Similar trials of the schedule of DEN are ongoing. ZA anticancer effect is only in postmenopausal women or premenopausal women rendered postmenopausal by GnRH agonists or bilateral oopherectomy. High-risk women, either postmenopausal or premenopausal, receiving GnRH/oopherctomy should consider adjuvant ZA. There are insufficient data to support DEN in this setting. Herein, this narrative review covers the mechanism of action of BMA, randomized clinical trials, and adverse events, both common and rare.