Bone cancer pain: from mechanism to therapy

Liu-Shen-Wan inhibits PI3K/Akt and TRPV1 signaling alleviating bone cancer pain in rats

Patients with advanced-stage cancers often suffer from severe pain caused by bone metastasis and destruction, for which effective treatment options are limited. Liu-Shen-Wan (LSW) is a widely recognized herbal formula utilized for pain relief. This study aims to elucidate the effects of LSW on bone cancer pain (BCP). In this study, the pharmacology of LSW on BCP was screened by network pharmacology. A BCP model was conducted using Walker 256 cells. Paw withdrawal threshold and paw withdrawal latency were employed as measures to assess the pain threshold in rats. The pathways and cell types of LSW against BCP were explored. Next, the impact of LSW on Walker 256 cells was evaluated, and UPLC-MS was utilized to identify the active ingredients of LSW. Furthermore, the effects of the key active ingredient, Bufalin, on the BCP rats were evaluated. There were 275 shared targets between LSW and BCP, which were enriched in neural tissue ligand-receptor interaction pathway. LSW increased pain threshold and decreased inflammatory cytokines levels in BCP rats by inhibiting PI3K/Akt and transient receptor potential vanilloid 1 (TRPV1) signaling through astrocytes and microglia. LY294002 further alleviated BCP in rats, while the effects were reversed after treatment with insulin-like growth factor 1 (IGF-1). Both LSW and its active ingredient Bufalin were shown to inhibit the viability and migration of Walker 256 cells and induce apoptosis. Bufalin appears to be the key active ingredient of LSW and exerts its pain-relieving effects by suppressing PI3K/Akt and TRPV1 signaling in BCP.

Curcumin analog C16 attenuates bone cancer pain induced by MADB 106 breast cancer cells in female rats and inhibits the CREB/NLGN2 signaling axis by targeting CaMKⅠα

Bone cancer pain (BCP) is one of the most severe complications faced by patients with cancer; however, current pharmacological options are limited. Curcumin has been demonstrated to possess anti-inflammatory and analgesic properties; however, our preliminary research found that the analgesic efficiency of curcumin is not high in BCP. Consequently, curcumin analogs have emerged as a significant focus of our research. This study aimed to systematically investigate the analgesic effects of C16 in rats with BCP induced by MADB 106 breast cancer cells (MADB 106-induced BCP) and elucidate the underlying molecular mechanisms. A range of experimental methods, including kinase profiling, transcriptome sequencing, behavioral tests, immunofluorescence, and biochemical analyses, were employed to comprehensively assess the role of C16 in the MADB 106-induced BCP model. The results indicated that C16 significantly alleviated bone cancer pain induced by Luciferin-MADB 106 cells (10^6 cells) in a dose-dependent manner. Importantly, kinase profiling and validation experiments identified CaMKIα in spinal dorsal horn neurons as the primary target of C16's analgesic effect on MADB 106-induced BCP. Continuous intrathecal administration of C16 markedly suppressed the expression of CREB and P-CREB and reduced the expression of neuroligin 2 in the spinal cords of BCP rats, thereby clarifying the mechanism of action of C16 in alleviating MADB 106-induced BCP. These findings suggest that C16 possesses significant therapeutic potential for mitigating MADB 106-induced BCP nociceptive hypersensitivity, providing a foundation for the future development of novel drugs targeting MADB 106-induced BCP.

Ossifying fibroma and juvenile ossifying fibroma: A systematic review on clinical and radiological parameters, treatment modalities and recurrence

Ossifying fibroma (OF) is a rare benign fibro-osseous neoplasm developing mostly in maxillo-facial bones. OF is divided in cemento-ossifying fibroma (COF), juvenile trabecular ossifying fibroma (JTOF) and psammomatoid ossifying fibroma (PSOF). The aim of this systematic review was to synthetize the existing literature on OF, investigating the clinical and radiological parameters related to the different forms of the disease, and to compare the treatment modalities according to their associated recurrence rate. Three databases were searched in March 2024, with an update in September 2024. Eligibility criteria included studies reporting on patients with OF, surgical treatment and follow-up data. Of the 2016 studies identified, 22 were retained after eligibility assessment. A total of 492 patients were included. Most OF presented with painless swelling. COF affected 61.1 % of women with a mean age of 29.5, JTOF presented in 55.7 % of male children, and PSOF had no predilection for sex with a mean age of 19.5 years. Enucleation and curettage were associated with an elevated recurrence rate in JTOF (12/30) and PSOF (10/16). PSOF (6 cases) and JTOF (15 cases) showed no recurrence with radical surgery. Same recurrence rates in COF were seen for conservative and radical surgery. Although radical surgery seemed to avoid recurrence in JTOF and PSOF, conservative surgery such as enucleation and curettage with additional peripheral ostectomy should be considered primarily to lessen the morbidity induced by radical resection. Close clinical and radiological follow-up should be undertaken to diagnose early recurrence.

Mesenchymal stem cell transplantation plays a role in relieving cancer pain

Tumors can invade, compress, and damage nerves, leading to persistent pain and seriously affecting the quality of life of patients. However, their treatment is challenging. Sensitization of peripheral receptors, abnormal activity of primary sensory neurons, activation of glial cells, enhanced inflammatory responses, and sensory information transmission contribute towards cancer pain. Therefore, considerable attention has been paid to exploring prospective methods to inhibit the occurrence of these factors and relieve cancer pain. Studies on different types of pains have revealed that the transplantation of functionally active cells into the host has the pharmacological effect of producing analgesia. Mesenchymal stem cells (MSCs) can act as small active pumps to reduce the expression of pain-related molecules and produce analgesic effects. Moreover, MSCs can establish complex communication networks with non-tumor and cancer cells in the microenvironment, interact with each other, and can be used as destinations for inflammation and tumor sites, affecting their potential for invasion and metastasis. This emphasizes the key role of MSCs in cancer and pain management. The pain relief mechanisms of MSCs include neuronutrition, neural protection, neural network reconstruction, immune regulation, and improvement of the inflammatory microenvironment around the nerve injury. All of these are beneficial for the recovery of injured or stimulated nerves and the reconstruction of neural function, and play a role in relieving pain. The pain treatment strategy of cell transplantation is to repair injured nerves and produce analgesic pharmacological properties that are different from those of painkillers and other physiotherapies. Although the therapeutic role of MSCs in cancer and pain is in its early stages, the therapeutic value of MSCs for cancer pain has great prospects. Therefore, in this study, we explored the possible mechanism between MSCs and cancer pain, the potential therapeutic role of therapeutic cells in cancer pain, and some problems and challenges.

Advancing Pain Understanding and Drug Discovery: Insights from Preclinical Models and Recent Research Findings

Despite major advancements in our understanding of its fundamental causes, pain-both acute and chronic-remains a serious health concern. Various preclinical investigations utilizing diverse animal, cellular, and alternative models are required and frequently demanded by regulatory approval bodies to bridge the gap between the lab and the clinic. Investigating naturally occurring painful disorders can speed up medication development at the preclinical and clinical levels by illuminating molecular pathways. A wide range of animal models related to pain have been developed to elucidate pathophysiological mechanisms and aid in identifying novel targets for treatment. Pain sometimes drugs fail clinically, causing high translational costs due to poor selection and the use of preclinical tools and reporting. To improve the study of pain in a clinical context, researchers have been creating innovative models over the past few decades that better represent pathological pain conditions. In this paper, we provide a summary of traditional animal models, including rodents, cellular models, human volunteers, and alternative models, as well as the specific characteristics of pain diseases they model. However, a more rigorous approach to preclinical research and cutting-edge analgesic technologies may be necessary to successfully create novel analgesics. The research highlights from this review emphasize new opportunities to develop research that includes animals and non-animals using proven methods pertinent to comprehending and treating human suffering. This review highlights the value of using a variety of modern pain models in animals before human trials. These models can help us understand the different mechanisms behind various pain types. This will ultimately lead to the development of more effective pain medications.

Palliative care in lung cancer: tumour- and treatment-related complications in lung cancer and their management

Palliative care pertains to the holistic multidimensional concept of "patient-centred" care. It is an interprofessional specialty, primarily aiming to improve quality of care for cancer patients and their families, from the time of diagnosis of malignant disease, over the continuum of cancer care, and extending after the patient's death to the period of bereavement to support the patient's family. There are various complex and frequently unmet needs of lung cancer patients and their families/caregivers, not only physical but also psychological, social, spiritual and cultural. Systematic monitoring of patients' symptoms using validated questionnaires and patient-reported outcomes (PROs), on a regular basis, is highly encouraged and recommended in recent guidelines on the role of PRO measures in the continuum of cancer clinical care. It improves patient-physician communication, physician awareness of symptoms, symptom control, patient satisfaction, health-related quality of life and cost-effectiveness. This implies that all treating physicians should improve their skills in communication with lung cancer patients/relatives and become more familiar with this multidimensional assessment, repeatedly screening patients for palliative care needs. Therefore, they should receive education and training to develop palliative care knowledge, skills and attitudes. This review is dedicated to lung cancer palliative care essentials that should be within the competences of treating physicians, i.e. pneumologists/thoracic oncologists.

The Role of Deubiquitinating Enzymes in Primary Bone Cancer

Bone is a living, intricate, and dynamic tissue providing locomotion and protection of the body. It also performs hematopoiesis and mineral homeostasis. Osteosarcoma (OS), Ewing sarcoma (ES), and chondrosarcoma (CS) are primary bone cancers. OS and ES mostly develop in younger individuals, and CS generally develops in adults. Ubiquitination regulates numerous cellular processes. The deubiquitinating enzymes (DUBs) detach the ubiquitin molecules from the ubiquitin labeled substrate, altering ubiquitinated protein functions and regulating protein stability via various signaling pathways. Protein homeostasis and bone remodeling are both crucially influenced by the UPS. Recently, there have been several reports on DUBs involved in bone homeostasis and various bone disorders through the regulation of osteoblasts and osteoclasts via NF-κB, Wnt/β-catenin, TRAF6, TGFβ, ERK1/2, and PI3K/Akt pathways. However, DUBs regulating function in bone homeostasis is still in its infancy. Here, we summarized several recent identifications on DUBs, with a focus on their role in bone cancer progression. Therefore, the study attempts to summarize association with the expression level of DUBs as key factors driving bone cancers and also provide new insights on DUBs as key pharmacologic targets for bone cancer therapeutics.

Systemic administration of Resolvin D1 reduces cancer-induced bone pain in mice: Lack of sex dependency in pain development and analgesia

AIMS

Bone cancer produces severe pain that is treated with opioids, but serious side effects limit opioid utilization. There is therefore a need to develop effective and safe non-opioid alternatives. The lipid mediator, Resolvin D1 (RvD1), could be a prospective candidate for cancer pain treatment. To assess RvD1 and other potential candidates, appropriate animal models that recapitulate clinical features must be used. Although several preclinical models of cancer pain have been developed, the influence of sex on the development of cancer pain and the effectiveness of RvD1 have not been studied.

RESULTS

Using a mouse model of fibrosarcoma growth in and around the calcaneus bone, we demonstrated that the mechanical hyperalgesia in the tumor-bearing hind paw develops independently of sex, except that it developed a little sooner in female mice. A single intravenous injection of RvD1 (0.001-10 μg/kg) decreased hyperalgesia in both sexes with similar potency (ED50 = 0.0015 μg/kg) and efficacy. Repeated daily administration of 10 μg/kg RvD1 prolonged the analgesic effect and completely abolished hyperalgesia. This was also independent of sex.

CONCLUSION

In this preclinical mouse model of bone cancer pain, the development of pain and the analgesic effectiveness of RvD1 are not influenced by sex.

Unveiling the therapeutic promise: exploring Lysophosphatidic Acid (LPA) signaling in malignant bone tumors for novel cancer treatments

Malignant bone tumors, including primary bone cancer and metastatic bone tumors, are a significant clinical challenge due to their high frequency of presentation, poor prognosis and lack of effective treatments and therapies. Bone tumors are often accompanied by skeletal complications such as bone destruction and cancer-induced bone pain. However, the mechanisms involved in bone cancer progression, bone metastasis and skeletal complications remain unclear. Lysophosphatidic acid (LPA), an intercellular lipid signaling molecule that exerts a wide range of biological effects mainly through specifically binding to LPA receptors (LPARs), has been found to be present at high levels in the ascites of bone tumor patients. Numerous studies have suggested that LPA plays a role in primary malignant bone tumors, bone metastasis, and skeletal complications. In this review, we summarize the role of LPA signaling in primary bone cancer, bone metastasis and skeletal complications. Modulating LPA signaling may represent a novel avenue for future therapeutic treatments for bone cancer, potentially improving patient prognosis and quality of life.

TrkA + sensory neurons regulate osteosarcoma proliferation and vascularization to promote disease progression

Bone pain is a presenting feature of bone cancers such as osteosarcoma (OS), relayed by skeletal-innervating peripheral afferent neurons. Potential functions of tumor-associated sensory neurons in bone cancers beyond pain sensation are unknown. To uncover neural regulatory functions, a chemical-genetic approach in mice with a knock-in allele for TrkA was used to functionally perturb sensory nerve innervation during OS growth and disease progression. TrkA inhibition in transgenic mice led to significant reductions in sarcoma-associated sensory innervation and vascularization, tumor growth and metastasis, and prolonged overall survival. Single-cell transcriptomics revealed that sarcoma denervation was associated with phenotypic alterations in both OS tumor cells and cells within the tumor microenvironment, and with reduced calcitonin gene-related peptide (CGRP) and vascular endothelial growth factor (VEGF) signaling. Multimodal and multi-omics analyses of human OS bone samples and human dorsal root ganglia neurons further implicated peripheral innervation and neurotrophin signaling in OS tumor biology. In order to curb tumor-associated axonal ingrowth, we next leveraged FDA-approved bupivacaine liposomes leading to significant reductions in sarcoma growth, vascularity, as well as alleviation of pain. In sum, TrkA-expressing peripheral neurons positively regulate key aspects of OS progression and sensory neural inhibition appears to disrupt calcitonin receptor signaling (CALCR) and VEGF signaling within the sarcoma microenvironment leading to significantly reduced tumor growth and improved survival. These data suggest that interventions to prevent pathological innervation of osteosarcoma represent a novel adjunctive therapy to improve clinical outcomes and survival.

MOTS-c is an effective target for treating cancer-induced bone pain through the induction of AMPK-mediated mitochondrial biogenesis

Bone cancer pain (BCP), due to cancer bone metastasis and bone destruction, is a common symptom of tumors, including breast, prostate, and lung tumors. Patients often experience severe pain without effective treatment. Here, using a mouse model of bone cancer, we report that MOTS-c, a novel mitochondrial-derived peptide, confers remarkable protection against cancer pain and bone destruction. Briefly, we find that the plasma level of endogenous MOTS-c is significantly lower in the BCP group than in the sham group. Accordingly, intraperitoneal administration of MOTS-c robustly attenuates bone cancer-induced pain. These effects are blocked by compound C, an AMPK inhibitor. Furthermore, MOTS-c treatment significantly enhances AMPKα 1/2 phosphorylation. Interestingly, mechanical studies indicate that at the spinal cord level, MOTS-c relieves pain by restoring mitochondrial biogenesis, suppressing microglial activation, and decreasing the production of inflammatory factors, which directly contribute to neuronal modulation. However, in the periphery, MOTS-c protects against local bone destruction by modulating osteoclast and immune cell function in the tumor microenvironment, providing long-term relief from cancer pain. Additionally, we find that chronic administration of MOTS-c has little effect on liver, renal, lipid or cardiac function in mice. In conclusion, MOTS-c improves BCP through peripheral and central synergistic effects on nociceptors, immune cells, and osteoclasts, providing a pharmacological and biological rationale for the development of mitochondrial peptide-based therapeutic agents for cancer-induced pain.

Targeting TRPV4 Channels for Cancer Pain Relief

Despite the unique and complex nature of cancer pain, the activation of different ion channels can be related to the initiation and maintenance of pain. The transient receptor potential vanilloid 4 (TRPV4) is a cation channel broadly expressed in sensory afferent neurons. This channel is activated by multiple stimuli to mediate pain perception associated with inflammatory and neuropathic pain. Here, we focused on summarizing the role of TRPV4 in cancer etiology and cancer-induced pain mechanisms. Many studies revealed that the administration of a TRPV4 antagonist and TRPV4 knockdown diminishes nociception in chemotherapy-induced peripheral neuropathy (CIPN). Although the evidence on TRPV4 channels' involvement in cancer pain is scarce, the expression of these receptors was reportedly enhanced in cancer-induced bone pain (CIBP), perineural, and orofacial cancer models following the inoculation of tumor cells to the bone marrow cavity, sciatic nerve, and tongue, respectively. Effective pain management is a continuous problem for patients diagnosed with cancer, and current guidelines fail to address a mechanism-based treatment. Therefore, examining new molecules with potential antinociceptive properties targeting TRPV4 modulation would be interesting. Identifying such agents could lead to the development of treatment strategies with improved pain-relieving effects and fewer adverse effects than the currently available analgesics.

Drug-drug interaction perpetrators of oxycodone in patients with cancer: frequency and clinical relevance

AIM

Oxycodone is known to have numerous drug-drug interactions (DDIs) that can potentially decrease efficacy or lead to adverse drug reactions (ADRs). However, there is limited research on the frequency of DDIs associated with oxycodone, which is important in optimising pharmacovigilance and the need for additional research on certain DDIs. In this study, the frequency of pharmacologically and clinically relevant DDI perpetrators was studied in patients with cancer.

METHODS

This was a cross-sectional study using hospital pharmacy records of patients with cancer who were prescribed oxycodone between September 2021 and September 2022. Medication records of patients prescribed oxycodone during a period of ≥ 5 consecutive days (= oxycodone treatment episodes) were reviewed to identify the concomitant use of pharmacologically relevant perpetrators, based on reference sources (Lexicomp®, Micromedex®, the Dutch Kennisbank and the Dutch Commentaren Medicatiebewaking). The clinical relevance was examined by a clinical pharmacologist and a medical oncologist. Additionally, the frequency of double interactions-concomitant oxycodone use with two CYP3A4 and / or CYP2D6 perpetrators-was studied.

RESULTS

Overall, 254 oxycodone treatment episodes were included, of which 227 (89.4%) were found to contain at least one pharmacologically relevant DDI perpetrator. Of these, 210 (82.7%) were considered to be clinically relevant. A total of 80 different pharmacologically relevant perpetrators were identified, with 65 (81.3%) being considered clinically relevant. Double interactions were observed in 21 (8.3%) oxycodone treatment episodes.

CONCLUSION

A high frequency of pharmacologically and clinically relevant perpetrators of oxycodone was observed in our cohort. Moreover, a high number of double interactions involving oxycodone was registered. More intense monitoring of DDIs may be needed to improve medication safety of patients with cancer taking oxycodone.

Ultrasound-guided pericapsular nerve group and obturator nerve phenol neurolysis for refractory inpatient hip cancer metastasis pain: a case report

INTRODUCTION

Bone cancer metastasis may produce severe and refractory pain. It is often difficult to manage with systemic analgesics. Chemical neurolysis may be an effective alternative in terminally ill patients.

CASE REPORT

Female terminally ill patient with hip metastasis of gastric cancer in severe pain. Neurolytic ultrasound-guided blocks of the pericapsular nerve group and obturator nerve were performed with 5% phenol. This led to satisfactory pain relief for 10 days, until the patient's death.

DISCUSSION

This approach may be effective and safe as an analgesic option for refractory hip pain due to metastasis or pathologic fracture in terminally ill patients.

Fat mass and obesity-related protein contributes to the development and maintenance of bone cancer pain in rats by abrogating m6A methylation of RNA

Effective prevention and treatment options for bone cancer-related pain (BCP) are lacking. In recent years, numerous studies have investigated the association between m6A epigenetic modifications and pain, revealing their significant role in pain initiation and maintenance. This study aimed to provide theoretical support for the treatment of BCP and to identify target drugs for future development. Specifically, we investigated the involvement of fat mass and obesity-related protein (FTO) in rat models of BCP by administering varying doses (1/5/10 mg/kg) of the FTO inhibitor meclofenamic acid (MA) and assessing changes in mechanical sensitivity through domain analysis, gait analysis, and open-field experiments. After successfully establishing the BCP model, we verified it by performing mechanical sensitivity assessments. We observed significantly increased expression levels of the demethylase FTO within the spinal dorsal horn accompanied by decreased m6A methylation levels in the model. Compared with untreated BCP rats, remarkably improved behavioral responses indicative of reduced pain were observed in the model rats after administration of 10 mg/kg MA, concomitant with decreased expression levels of FTO and increased m6A methylation levels. Compared with untreated BCP rats, the expression levels of p-ERK and pro-inflammatory cytokines were also significantly decreased after MA administration. Taken together, FTO can downregulate m6A methylation level and activate ERK/inflammatory cytokines signaling pathway to maintain BCP in rats.

Evaluation of pain related behaviors and disease related outcomes in an immunocompetent mouse model of prostate cancer induced bone pain

Cancer-induced bone pain (CIBP) is the most common and devastating symptom of bone metastatic cancer that substantially disrupts patients' quality of life. Currently, there are few effective analgesic treatments for CIBP other than opioids which come with severe side effects. In order to better understand the factors and mechanisms responsible for CIBP it is essential to have clinically relevant animal models that mirror pain-related symptoms and disease progression observed in patients with bone metastatic cancer. In the current study, we characterize a syngeneic mouse model of prostate cancer induced bone pain. We transfected a prostate cancer cell line (RM1) with green fluorescent protein (GFP) and luciferase reporters in order to visualize tumor growth longitudinally in vivo and to assess the relationship between sensory neurons and tumor cells within the bone microenvironment. Following intra-femoral injection of the RM1 prostate cancer cell line into male C57BL/6 mice, we observed a progressive increase in spontaneous guarding of the inoculated limb between 12 and 21 days post inoculation in tumor bearing compared to sham operated mice. Daily running wheel performance was evaluated as a measure of functional impairment and potentially movement evoked pain. We observed a progressive reduction in the distance traveled and percentage of time at optimal velocity between 12 and 21 days post inoculation in tumor bearing compared to sham operated mice. We utilized histological, radiographic and μCT analysis to examine tumor induced bone remodeling and observed osteolytic lesions as well as extra-periosteal aberrant bone formation in the tumor bearing femur, similar to clinical findings in patients with bone metastatic prostate cancer. Within the tumor bearing femur, we observed reorganization of blood vessels, macrophage and nerve fibers within the intramedullary space and periosteum adjacent to tumor cells. Tumor bearing mice displayed significant increases in the injury marker ATF3 and upregulation of the neuropeptides SP and CGRP in the ipsilateral DRG as well as increased measures of central sensitization and glial activation in the ipsilateral spinal cord. This immunocompetent mouse model will be useful when combined with cell type selective transgenic mice to examine tumor, immune cell and sensory neuron interactions in the bone microenvironment and their role in pain and disease progression associated with bone metastatic prostate cancer.

A Rare Skeletal Disorder, Fibrous Dysplasia: A Review of Its Pathogenesis and Therapeutic Prospects

Fibrous dysplasia (FD) is a rare, non-hereditary skeletal disorder characterized by its chronic course of non-neoplastic fibrous tissue buildup in place of healthy bone. A myriad of factors have been associated with its onset and progression. Perturbation of cell-cell signaling networks and response outputs leading to disrupted building blocks, incoherent multi-level organization, and loss of rigid structural motifs in mineralized tissues are factors that have been identified to participate in FD induction. In more recent years, novel insights into the unique biology of FD are transforming our understandings of its pathology, natural discourse of the disease, and treatment prospects. Herein, we built upon existing knowledge with recent findings to review clinical, etiologic, and histological features of FD and discussed known and potential mechanisms underlying FD manifestations. Subsequently, we ended on a note of optimism by highlighting emerging therapeutic approaches aimed at either halting or ameliorating disease progression.

HIF-1α/MMP-9 promotes spinal cord central sensitization in rats with bone cancer pain

Bone cancer pain (BCP) is one of the most prevalent and serious symptoms of patients with cancer. Currently, the medical interventions used for the treatment of BCP do not act with optimal safety and efficacy. In this study, we appraised whether the hypoxia-inducible factor 1α (HIF-1α)/metalloproteinase-9 (MMP9) axis activates the PI3K/AKT pathway, resulting in elevated spinal cord central sensitization and aggravated BCP. BCP rats were established by tibial injection of Walker 256 cells, followed by different interventions in rats using HIF-1ɑ inhibitor LW6 or antibody treatments. After treatment with LW6 or antibody against HIF-1α, central sensitization in the spinal cord tissues of rats was inhibited, and pain perception in rats was reduced. Moreover, the activation of glial cells in the spinal cord tissues was ameliorated. The expression of MMP9 was remarkably suppressed in spinal cord tissues after inhibition of HIF-1ɑ activity, and the activity of the PI3K/AKT signaling pathway was inhibited. Further activation of MMP9 expression suppressed the alleviating effect of HIF-1ɑ inhibitor LW6 or antibody on pain perception in rats inoculated with tumors. Taken together, our studies suggest a HIF-1α/MMP9-mediated activation of PI3K/AKT in the spinal cord tissues, resulting in increased pain perception in a rat model with BCP.

Differences in the Analgesic Effect of Opioids on Pain in Cancer Patients With Spinal Metastases

Background

Spinal metastasis pain includes both inflammatory and neuropathic pain, and opioids, which have only a μ-opioid receptor-stimulating effect, are generally less effective in neuropathic pain. However, no previous study has been conducted for the comparisons of the efficacy of opioids in treating spinal metastasis pain.

Objective

To compare the efficacy of tapentadol and methadone with other opioids for back pain caused by a metastatic spinal tumor.

Design

Retrospective cohort study.

Setting/Subjects

A total of 274 patients were enrolled, who started a tapentadol extended-release tablet, methadone tablet, hydromorphone extended-release tablet, oxycodone extended-release tablet, or transdermal fentanyl patch for cancer pain due to spinal metastasis in Japan from January 1, 2013 to October 31, 2021.

Measurements

The primary endpoint, the difference in the numerical rating scale (NRS) scores before and seven days after each opioid administration, was compared among the five groups.

Results

In patients with numbness, a decrease of the NRS score on day seven compared with before starting each opioid was significantly higher in the tapentadol group than those in the hydromorphone, oxycodone, and fentanyl groups and comparable to that in the methadone group. In patients without numbness, no significant differences were observed in decreases of the NRS scores on day seven among the five groups.

Conclusions

Tapentadol and methadone may be more effective than hydromorphone, oxycodone, and fentanyl for cancer pain due to spinal metastasis with numbness.

Downregulated CAV-1 in mouse spinal cord may alleviate bone cancer pain by inhibiting the ERK/CREB pathway

BACKGROUND

This study aimed to assess the potential function of Caveolin-1 (CAV-1) in mice with bone cancer pain.

METHOD

Using a mice bone cancer pain model we explored the contribution of CAV-1 expression to bone cancer pain on the 14th day after surgery, mice in the tumor group were randomized and treated with increasing doses of the CAV-1 inhibitor, methyl-beta-cyclodextrin. Pain was assessed by monitoring the number of spontaneous flinches (NSF) and paw withdrawal mechanical threshold (PMWT)mechanical withdrawal threshold (MWT). The localization and expression of CAV-1 in mouse neurons was also determined. Additionally, the protein levels of CAV-1, extracellular signal regulated kinase (ERK) 1/2, cAMP response element-binding protein (CREB) were monitored in mouse spinal cord tissues by western blotting.

RESULTS

CAV-1 was remarkably upregulated in the spinal cord of the tumor group on the 4th day after surgery, then downregulated on day 10, and upregulated again at day 14. Such CAV-1 levels were maintained until day 28. In the tumor group, the expression of p-ERK1/2 and p-CERB were upregulated at day 14 after surgery. Intrathecal injection of methyl-beta-cyclodextrin (MCD) downregulated p-ERK1/2 and p-CERB expression which correlated with alleviation of pain.

CONCLUSION

Inhibition of CAV-1 in the spinal cord alleviates bone cancer pain in mice which correlates with inhibition of the ERK/CREB pathway.

Cancer-nerve interplay in cancer progression and cancer-induced bone pain

INTRODUCTION

Cancer-induced bone pain (CIBP) is one of the most common and debilitating complications associated with bone metastasis. Although our understanding of the precise mechanism is limited, it has been known that bone is densely innervated, and that CIBP is elicited as a consequence of increased neurogenesis, reprogramming, and axonogenesis in conjunction with sensitization and excitation of sensory nerves (SNs) in response to the noxious stimuli that are derived from the tumor microenvironment developed in bone. Recent studies have shown that the sensitized and excited nerves innervating the tumor establish intimate communications with cancer cells by releasing various tumor-stimulating factors for tumor progression.

APPROACHES

In this review, the role of the interactions of cancer cells and SNs in bone in the pathophysiology of CIBP will be discussed with a special focus on the role of the noxious acidic tumor microenvironment, considering that bone is in nature hypoxic, which facilitates the generation of acidic conditions by cancer. Subsequently, the role of SNs in the regulation of cancer progression in the bone will be discussed together with our recent experimental findings.

CONCLUSION

It is suggested that SNs may be a newly-recognized important component of the bone microenvironment that contribute to not only in the pathophysiology of CIBP but also cancer progression in bone and dissemination from bone. Suppression of the activity of bone-innervating SNs, thus, may provide unique opportunities in the treatment of cancer progression and dissemination, as well as CIBP.

The Edmonton Classification System for Cancer Pain in Patients with Bone Metastasis: a descriptive cohort study

PURPOSE

We describe the prevalence of the Edmonton Classification System for Cancer Pain (ECS-CP) features in patients with bone metastasis and cancer-induced bone pain (CIBP) and the relationship between ECS-CP features, pain intensity, and opioid consumption.

METHODS

We assessed ECS-CP features and recoded pain mechanisms and opioid use in adult patients with bone metastasis. Validated measures were used to assess pain intensity, incident pain, psychological distress, addictive behavior, and cognition.

RESULTS

Among 147 eligible patients, 95.2% completed the assessment. Mean participant age was 73.2 years, the majority female (52.1%) with breast cancer occurring most commonly (25.7%). One or more ECS-CP features were present in 96.4% and CIBP in 75.7% of patients. The median average and worst pain scores were 3 and 6, respectively. Neuropathic pain was the most prevalent pain mechanism (45.0%) and was associated with breakthrough pain frequency (p=0.014). Three-quarters had incident pain, which was strongly associated with a higher average and worst pain scores (3.5 and 7, p<0.001 for both), background oral morphine equivalent daily dose (26.7mg, p=0.005), and frequency of daily breakthrough analgesia (1.7 doses/day, p=0.007). Psychological distress (n=90, 64.3%) was associated with a significantly higher average pain score (4, p=0.009) and a slightly higher worst pain score (7, p=0.054). Addictive behaviour and cognitive dysfunction were relatively uncommon (18.6% and 12.9%, respectively).

CONCLUSION

There is a need to promote standardized assessment and classification of pain syndromes such as CIBP. The ECS-CP may allow us to consider CIBP in a systematic manner and develop personalized pain interventions appropriate to the pain profile.

TRIAL REGISTRATION

Retrospectively registered in ANZCTR ACTRN12622000853741 (16/06/2022).

Inhibition of spinal ferroptosis-like cell death alleviates hyperalgesia and spontaneous pain in a mouse model of bone cancer pain

Bone cancer pain (BCP) impairs patients' quality of life. However, the underlying mechanisms are still unclear. This study investigated the role of spinal interneuron death using a pharmacological inhibitor of ferroptosis in a mouse model of BCP. Lewis lung carcinoma cells were inoculated into the femur, resulting in hyperalgesia and spontaneous pain. Biochemical analysis revealed that spinal levels of reactive oxygen species and malondialdehyde were increased, while those of superoxide dismutase were decreased. Histological analysis showed the loss of spinal GAD65+ interneurons and provided ultrastructural evidence of mitochondrial shrinkage. Pharmacologic inhibition of ferroptosis using ferrostatin-1 (FER-1, 10 mg/kg, intraperitoneal for 20 consecutive days) attenuated ferroptosis-associated iron accumulation and lipid peroxidation and alleviated BCP. Furthermore, FER-1 inhibited the pain-associated activation of ERK1/2 and COX-2 expression and prevented the loss of GABAergic interneurons. Moreover, FER-1 improved analgesia by the COX-2 inhibitor Parecoxib. Taken together, this study shows that pharmacological inhibition of ferroptosis-like cell death of spinal interneurons alleviates BCP in mice. The results suggest that ferroptosis is a potential therapeutic target in patients suffering on BCP and possibly other types of pain.

Lung Cancer Supportive Care and Symptom Management

Lung cancer carries significant mortality and morbidity. In addition to treatment advances, supportive care may provide significant benefit for patients and their caregivers. A multidisciplinary approach is critical in addressing complications of lung cancer, including disease- and treatment-related complications, oncologic emergencies, symptom management and supportive care, and addressing the psychosocial needs of affected patients.

Schwann Cell Insulin-like Growth Factor Receptor Type-1 Mediates Metastatic Bone Cancer Pain in Mice

Insulin growth factor-1 (IGF-1), an osteoclast-dependent osteolysis biomarker, contributes to metastatic bone cancer pain (MBCP), but the underlying mechanism is poorly understood. In mice, the femur metastasis caused by intramammary inoculation of breast cancer cells resulted in IGF-1 increase in femur and sciatic nerve, and IGF-1-dependent stimulus/non-stimulus-evoked pain-like behaviors. Adeno-associated virus-based shRNA selective silencing of IGF-1 receptor (IGF-1R) in Schwann cells, but not in dorsal root ganglion (DRG) neurons, attenuated pain-like behaviors. Intraplantar IGF-1 evoked acute nociception and mechanical/cold allodynia, which were reduced by selective IGF-1R silencing in DRG neurons and Schwann cells, respectively. Schwann cell IGF-1R signaling promoted an endothelial nitric oxide synthase-mediated transient receptor potential ankyrin 1 (TRPA1) activation and release of reactive oxygen species that, via macrophage-colony stimulating factor-dependent endoneurial macrophage expansion, sustained pain-like behaviors. Osteoclast derived IGF-1 initiates a Schwann cell-dependent neuroinflammatory response that sustains a proalgesic pathway that provides new options for MBCP treatment.

Primary Bone Lymphoma: A Review of the Literature with Emphasis on Histopathology and Histogenesis

Primary bone lymphoma (PBL) is a rare neoplasm of malignant lymphoid cells presenting with one or more bone lesions without nodal or other extranodal involvement. It accounts for approximately 1% of all lymphomas and 7% of malignant primary bone tumors. Diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) represents the predominant histological type and constitutes over 80% of all cases. PBL may occur at all ages with a typical diagnosis age of 45–60 years and a slight male predominance. Local bone pain, soft tissue edema, palpable mass and pathological fracture are the most common clinical features. Diagnosis of the disease, which is frequently delayed due to its non-specific clinical presentation, is based on the combination of clinical examination and imaging studies and confirmed by combined histopathological and immunohistochemical examination. PBL can develop in any part of the skeleton, although it occurs most commonly in the femur, humerus, tibia, spine and pelvis. The imaging appearance of PBL is highly variable and unspecific. In terms of the cell-of-origin, most cases of primary bone DLBCL (PB-DLBCL), NOS belong to the germinal center B-cell-like subtype and specifically originate from germinal center centrocytes. PB-DLBCL, NOS has been considered a distinct clinical entity based on its particular prognosis, histogenesis, gene expression and mutational profile and miRNA signature. PBL carries a favorable prognosis, especially when treated with combined chemoradiotherapy.

Pharmacological Interventions Targeting Pain in Fibrous Dysplasia/McCune-Albright Syndrome

Fibrous dysplasia (FD) is a rare, non-inherited bone disease occurring following a somatic gain-of-function R201 missense mutation of the guanine-nucleotide binding protein alpha subunit stimulating activity polypeptide 1 (GNAS) gene. The spectrum of the disease ranges from a single FD lesion to a combination with extraskeletal features; an amalgamation with café-au-lait skin hyperpigmentation, precocious puberty, and other endocrinopathies defines McCune-Albright Syndrome (MAS). Pain in FD/MAS represents one of the most prominent aspects of the disease and one of the most challenging to treat-an outcome driven by (i) the heterogeneous nature of FD/MAS, (ii) the variable presentation of pain phenotypes (i.e., craniofacial vs. musculoskeletal pain), (iii) a lack of studies probing pain mechanisms, and (iv) a lack of rigorously validated analgesic strategies in FD/MAS. At present, a range of pharmacotherapies are prescribed to patients with FD/MAS to mitigate skeletal disease activity, as well as pain. We analyze evidence guiding the current use of bisphosphonates, denosumab, and other therapies in FD/MAS, and also discuss the potential underlying pharmacological mechanisms by which pain relief may be achieved. Furthermore, we highlight the range of presentation of pain in individual cases of FD/MAS to further describe the difficulties associated with employing effective pain treatment in FD/MAS. Potential next steps toward identifying and validating effective pain treatments in FD/MAS are discussed, such as employing randomized control trials and probing new pain pathways in this rare bone disease.

Factors Influencing the Adoption of Magnetic Resonance-Guided High-Intensity Focused Ultrasound for Painful Bone Metastases in Europe, A Group Concept Mapping Study

Magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) is an innovative treatment for patients with painful bone metastases. The adoption of MR-HIFU will be influenced by several factors beyond its effectiveness. To identify contextual factors affecting the adoption of MR-HIFU, we conducted a group concept mapping (GCM) study in four European countries. The GCM was conducted in two phases. First, the participants brainstormed statements guided by the focus prompt "One factor that may influence the uptake of MR-HIFU in clinical practice is...". Second, the participants sorted statements into categories and rated the statements according to their importance and changeability. To generate a concept map, multidimensional scaling and cluster analysis were conducted, and average ratings for each (cluster of) factors were calculated. Forty-five participants contributed to phase I and/or II (56% overall participation rate). The resulting concept map comprises 49 factors, organized in 12 clusters: "competitive treatments", "physicians' attitudes", "alignment of resources", "logistics and workflow", "technical disadvantages", "radiotherapy as first-line therapy", "aggregating knowledge and improving awareness", "clinical effectiveness", "patients' preferences", "reimbursement", "cost-effectiveness" and "hospital costs". The factors identified echo those from the literature, but their relevance and interrelationship are case-specific. Besides evidence on clinical effectiveness, contextual factors from 10 other clusters should be addressed to support adoption of MR-HIFU.

The role and pharmacological properties of P2Y12 receptor in cancer and cancer pain

The G protein-coupled P2Y12 receptor (P2Y12R) was cloned in platelets and found to play a key role in maintaining platelet function in hemostasis and thrombosis, and these effects could be mediated by the P2Y12R. However, it has recently been found that P2Y12R-mediated the progression of tumor through interactions between platelets and tumor and stromal cells, as well as through products secreted by platelets. During tumor progression, tumor cells or other cells in the tumor microenvironment (such as immune cells) can secrete large amounts of ATP into the extracellular matrix, and extracellular ATP can be hydrolyzed into ADP. ADP is a P2Y12R activator and plays an important regulatory role in the proliferation and metastasis of tumor cells. P2Y12R is involved in platelet-cancer cell crosstalk and become a potential target for anticancer therapy. Moreover, tumor progression can induce pain, which seriously affects the quality of life of patients. P2Y12R is expressed in microglia and mediates the activities of microglial and participates in the occurrence of cancer pain. Conversely, inhibiting P2Y12R activation and down-regulating its expression has the effect of inhibiting tumor progression and pain. Therefore, P2Y12R can be a common therapeutic target for both. In this article, we explored the potential link between P2Y12R and cancer, discussed the intrinsic link of P2Y12R in cancer pain and the pharmacological properties of P2Y12R antagonists in the treatment of both.

The effect of Orem's nursing theory on the pain levels, self-care abilities, psychological statuses, and quality of life of bone cancer patients

OBJECTIVE

This study aims to explore the impact of Orem-based nursing intervention on the pain levels, self-care abilities, psychological statuses, and quality of life in bone cancer patients.

METHODS

A total of 91 patients with primary bone cancer admitted to our hospital from January 2019 to January 2020 were randomly placed into one of two groups. The patients in the control group (n=43) underwent routine nursing care, and the patients in the experimental group (n=48) underwent Orem-based nursing care during the perioperative period. The two groups were compared in terms of their postoperative recovery times and treatment effects, and their adverse emotion scores, pain levels, self-care abilities, and quality of life before and after intervention.

RESULTS

The treatment efficacy in the two groups was similar, but the postoperative recovery times in the experimental group were shorter than they were in the control group (P < 0.05). Compared with before the intervention, the SDS, SAS, and VAS scores were significantly decreased in both groups (P < 0.05), and their self-care abilities and quality of life were significantly higher (P < 0.05) after intervention.

CONCLUSION

Orem-based nursing combined with perioperative care can mobilize patients' initiative, significantly improve patients' adverse emotions and pain levels, shorten their postoperative recovery times, and help improve their self-care abilities and quality of life.

The trend of opioid prescriptions among cancer patients in a tertiary hospital: A multimethod quantitative study

Introduction

Pain is a major symptom in cancer patients. World Health Organization recommends opioids as the main analgesic agent. Few studies have examined the amount of opioid uses in cancer patients in Southeast Asia, however, none of them have examined the factors associated with the amount of opioid uses which were lower than required.

Objectives

To assess the trends and factors associated with opioid prescriptions for cancer patients in Songklanagarind Hospital, the largest referral center in Southern Thailand.

Design

Multi-method quantitative study.

Methods

We reviewed the electronic medical records of 20,192, outpatients aged ≥18 years diagnosed with cancer between 2016 and 2020 who received opiod prescriptions. Oral morphine equivalents (OME) were calculated using the standard conversion factors and the OME trend during the study period was assessed by a generalized additive model. Factors affecting the morphine equivalent daily dose (MEDD) were assessed using multiple linear regression with a generalized estimating equation.

Results

The mean overall MEDD for all study patients was 27.8 ± 21.9 mg per day per patient. The bone and articular cartilage cancer patients had the highest MEDD. For every 5-year increase in the duration of cancer, the MEDD increased by 0.02 (95% confidence interval [CI]: 0.01 - 0.04). Patients with stage 4 cancer received a higher average MEDD of 4.04 (95% CI: 0.30-7.62) as compared to those with stage 1 cancer. Patients with bone metastasis received a average higher MEDD of 4.03 (95% CI: 0.82-7.19) compared to those without. Age was inversely associated with the MEDD. Patients aged 42-58, 59-75 and >76years old received MEDDs of 4.73 (95% CI: 2.31-7.15), 6.12 (95% CI: 3.66-8.59) and 8.59 (95% CI: 6.09-11.09) compared with those aged 18-42 years old. Brain metastasis was inversely associated with MEDD of 4.49 (95% CI: 0.61-8.37) compared to those without.

Conclusion

Opioid use in cancer patients in this study is lower than the average global usage. Promoting opioid prescriptions for pain management through medical education can help doctors overcome opiophobia.

Activation of HCN channels caused by elevated cAMP levels in periaqueductal gray promotes bone cancer pain

The periaqueductal gray (PAG) is an important relay center for the descending pathways that regulate nociceptive information transduction. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels play critical roles in the nerve injury-induced pain hypersensitivity. Previous studies have identified that HCN1 and HCN2 channel protein located in the ventral-lateral periaqueductal gray (vlPAG), a region important for pain regulation. However, it is not clear whether the HCN channel in vlPAG is involved in bone cancer pain (BCP). In this study, we assessed the role of HCN channels in BCP by measuring changes of HCN channel expression and activity in vlPAG neurons in bone cancer rats. In the present study, the BCP model was established by injecting SHZ-88 breast cancer cells into the right tibia bone marrow in rats. The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured to evaluate pain behavior in rats. HCN1 and HCN2 channels expression in vlPAG were detected by using Western Blot and immunohistochemistry. In addition, the cAMP level in vlPAG neurons was detected by ELISA, and HCN channel current (I_h) of vlPAG neurons was recorded by whole cell patch-clamp to evaluate HCN channel activity. As a result, decreased MWT and TWL were observed in rats on 7d after SHZ-88 cell inoculation, and the allodynia was sustained until 21d after inoculation. At the same time, HCN1 and HCN2 channels expression and neuronal I_h in vlPAG were significantly increased in BCP rats. In addition, the level of cAMP in vlPAG also increased after SHZ-88 cell inoculation. Furthermore, intravlPAG injection of ZD7288 (HCN channels antagonist) could significantly reduce hyperalgesia and the elevation of cAMP in vlPAG in BCP rats. Our observations suggest that the elevation of cAMP may promote the activation of HCN channels in vlPAG in bone cancer rats, thereby promoting the development of bone cancer pain.

Focused Ultrasound and RadioTHERapy for non-invasive palliative pain treatment in patients with bone metastasis: a study protocol for the three armed randomized controlled FURTHER trial

BACKGROUND

Cancer-induced bone pain (CIBP), caused by bone metastases, is a common complication of cancer and strongly impairs quality of life (QoL). External beam radiotherapy (EBRT) is the current standard of care for treatment of CIBP. However, approximately 45% of patients have no adequate pain response after EBRT. Magnetic resonance image-guided high-intensity focused ultrasound (MR-HIFU) may improve pain palliation in this patient population. The main objective of this trial was to compare MR-HIFU, EBRT, and MR-HIFU + EBRT for the palliative treatment of bone metastases.

METHODS/DESIGN

The FURTHER trial is an international multicenter, three-armed randomized controlled trial. A total of 216 patients with painful bone metastases will be randomized in a 1:1:1 ratio to receive EBRT only, MR-HIFU only, or combined treatment with EBRT followed by MR-HIFU. During a follow-up period of 6 months, patients will be contacted at eight time points to retrieve information about their level of pain, QoL, and the occurrence of (serious) adverse events. The primary outcome of the trial is pain response at 14 days after start of treatment. Secondary outcomes include pain response at 14 days after trial enrolment, pain scores (daily until the 21st day and at 4, 6, 12 and 24 weeks), toxicity, adverse events, QoL, and survival. Cost-effectiveness and cost-utility analysis will be conducted.

DISCUSSION

The FURTHER trial aims to evaluate the effectiveness and cost-effectiveness of MR-HIFU-alone or in combination with EBRT-compared to EBRT to relieve CIBP. The trial will be performed in six hospitals in four European countries, all of which are partners in the FURTHER consortium.

TRIAL REGISTRATION

The FURTHER trial is registered under the Netherlands Trials Register number NL71303.041.19 and ClinicalTrials.gov registration number NCT04307914. Date of trial registration is 13-01-2020.

The impacts of exosomes on bone metastatic progression and their potential clinical utility

Bone is one of the most common sites of cancer metastasis. Once cancer metastasizes to the bone, the mortality rate of cancer patients dramatically increases. Although the exact mechanisms for this observation remain elusive, recent studies have revealed that the complex crosstalk between bone marrow microenvironment and bone metastatic cancer cells is responsible for the induction of treatment resistance. Consequently, bone metastasis is currently considered incurable. Bone metastasis not only impairs the patients' survival, but also negatively affects their quality of life by causing painful complications. It has recently been implicated the regulatory role of exosomes in cancer development and/or progression as a delivery biomaterial between cancer cells and tumor microenvironment. However, little is known as to how exosomes contribute to the progression of bone metastasis by impaction on the crosstalk between bone metastatic cancer cells and bone marrow microenvironment. Here, we highlighted the emerging roles of cancer-derived exosomes in (i) the process of dissemination and bone colonization of bone metastatic cancer cells, (ii) the enhancement of crosstalk between bone marrow microenvironment and bone metastatic cancer cells, (iii) the development of its resultant painful complications, and (iv) the clinical applications of exosomes in the bone metastatic setting.

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Cancer-derived exosomes facilitate cancer dissemination and colonization to bone.

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Cancer-derived exosomes are crucial for controlling bone metastatic phenotype.

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Cancer-derived exosomes prime bone marrow microenvironment for further metastasis.

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Cancer-derived exosomes are involved in development of cancer-induced bone pain.

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Exosomes can be used as therapies and/or diagnostic tools for bone metastasis.

The Burden of Metastatic Cancer-Induced Bone Pain: A Narrative Review

Bone pain is one of the most common forms of pain reported by cancer patients with metastatic disease. We conducted a review of oncology literature to further understand the epidemiology of and treatment approaches for metastatic cancer–induced bone pain and the effect of treatment of painful bone metastases on the patient’s quality of life. Two-thirds of patients with advanced, metastatic, or terminal cancer worldwide experience pain. Cancer pain due to bone metastases is the most common form of pain in patients with advanced disease and has been shown to significantly reduce patients’ quality of life. Treatment options for cancer pain due to bone metastases include nonsteroidal anti-inflammatory drugs, palliative radiation, bisphosphonates, denosumab, and opioids. Therapies including palliative radiation and opioids have strong evidence supporting their efficacy treating cancer pain due to bone metastases; other therapies, like bisphosphonates and denosumab, do not. There is sufficient evidence that patients who experience pain relief after radiation therapy have improved quality of life; however, a substantial proportion are nonresponders. For those still requiring pain management, even with available analgesics, many patients are undertreated for cancer pain due to bone metastases, indicating an unmet need. The studies in this review were not designed to determine why cancer pain due to bone metastases was undertreated. Studies specifically addressing cancer pain due to bone metastases, rather than general cancer pain, are limited. Additional research is needed to determine patient preferences and physician attitudes regarding choice of analgesic for moderate to severe cancer pain due to bone metastases.

Prostate cancer induced bone pain: pathobiology, current treatments and pain responses from recent clinical trials

PURPOSE

Metastatic spread of prostate cancer to the skeleton may result in debilitating bone pain. In this review, we address mechanisms underpinning the pathobiology of metastatic prostate cancer induced bone pain (PCIBP) that include sensitization and sprouting of primary afferent sensory nerve fibres in bone. We also review current treatments and pain responses evoked by various treatment modalities in clinical trials in this patient population.

METHODS

We reviewed the literature using PubMed to identify research on the pathobiology of PCIBP. Additionally, we reviewed clinical trials of various treatment modalities in patients with PCIBP with pain response outcomes published in the past 7 years.

RESULTS

Recent clinical trials show that radionuclides, given either alone or in combination with chemotherapy, evoked favourable pain responses in many patients and a single fraction of local external beam radiation therapy was as effective as multiple fractions. However, treatment with chemotherapy, small molecule inhibitors and/or immunotherapy agents, produced variable pain responses but pain response was the primary endpoint in only one of these trials. Additionally, there were no published trials of potentially novel analgesic agents in patients with PCIBP.

CONCLUSION

There is a knowledge gap for clinical trials of chemotherapy, small molecule inhibitors and/or immunotherapy in patients with PCIBP where pain response is the primary endpoint. Also, there are no novel analgesic agents on the horizon for the relief of PCIBP and this is an area of large unmet medical need that warrants concerted research attention.

Guideline and Implementation of Osteosarcoma Nursing Care for Children and Adolescents

Clinical trials on pediatric oncology use therapeutic techniques with the overwhelming majority of children's cancer patients obtaining therapy via clinical investigation procedures. Medical treatment is scheduled according to a specific protocol for enrolled patients. These protocols often do not refer to nursing care. Nursing care, on the other hand, must complement the medical care specified in the medical research protocol. Safe treatment administration, assessment of treatment responses, patients' and families' education, and communication with the whole medical team are just a few of the critical nursing tasks that should be properly managed. Nursing care standards have been developed in this study to strike a good balance between the procedure for clinical research and the nursing care connected with it. These recommendations outline the nursing activities and considerations that must be made while caring for pediatric cancer patients who are engaged in a specific clinical investigation procedure. The objective of this study is to outline the procedure through which nursing care guidelines could be developed and evaluated. The goal of this study was to find out the involvement of nurses in the process of health education for osteosarcoma and family patients.

The effect of music on pain and anxiety in patients receiving chemotherapy during COVID-19

OBJECTIVE

This research has been conducted to determine the effect of music on pain and anxiety levels of patients receiving chemotherapy during COVID-19.

METHODS

The research has been carried out in a real trial model with 92 adult patients (45 in the experimental group who received chemotherapy and 47 in the control group). The data have been collected by the researcher with Google Forms (using State and Trait Anxiety Inventory [STAI] and visual analogue scale [VAS]) through the links sent to the phones of participants on the day they received chemotherapy, between March 2020 and July 2020.

RESULTS

The mean scores obtained from the post-test STAI (53.11 ± 4.77) and VAS (3.44 ± 2.53) in the experimental group have been determined to statistically significantly decrease when compared to the pre-test measurement data (STAI: 54.26 ± 4.26; VAS: 4.22 ± 2.41) (p < 0.05). No statistically significant difference has been determined between pre-test and post-test mean scores of the patients in the control group.

CONCLUSION

It has been observed that music applications reduce the pain and anxiety levels of patients receiving chemotherapy during the COVID-19 process. It can be recommended to use music applications in the management of pain and anxiety symptoms.

β-Elemene Improves Morphine Tolerance in Bone Cancer Pain via N-Methyl-D-Aspartate Receptor 2B Subunit-Mediated μ-Opioid Receptor

Background

Improving morphine tolerance (MT) is an urgent problem in the clinical treatment of bone cancer pain. Considering that β-Elemene is widely used in the treatment of cancer pain, we explored the effects and mechanism of β-Elemene in preventing MT of bone cancer pain.

Method

Bone cancer pain and chronic MT rat model was established by injecting MADB106 cells and morphine (10 mg/kg). SH-SY5Y cells were treated with morphine (10 μg/mL) for 48 h to establish a cell model. The mechanical withdrawal threshold and thermal withdrawal latency of rats were detected by mechanical allodynia and thermal hyperalgesia tests, respectively. The protein expressions of μ-opioid receptor (MOPR), cyclic adenosine monophosphate (cAMP), N-methyl-D-aspartate receptor subunit 2B (NR2B), phosphorylated-calmodulin-dependent protein kinase II (p-CaMKII), and CaMKII were detected by western blot. The viability of SH-SY5Y cells was determined by the cell counting kit-8 assay. cAMP content in SH-SY5Y cells was measured by a LANCE cAMP kit.

Result

Animal experiments showed that MT strengthened over time, while increased β-Elemene dosage alleviated MT. The viability of SH-SY5Y cells was down-regulated by high-dose β-Elemene. In the rat and cell models, long-term morphine treatment decreased the expression of MOPR and increased the cAMP and NR2B expressions and p-CaMKII/CaMKII, while β-Elemene and siNR2B counteracted the effects of morphine treatment. In addition, siNR2B reversed the effects of β-Elemene on related protein expressions and cAMP content in the cell model.

Conclusion

β-Elemene improved MT in bone cancer pain through the regulation of NR2B-mediated MOPR.

Traditional processing, uses, phytochemistry, pharmacology and toxicology of Aconitum sinomontanum Nakai: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

As a folk medicine, Aconitum sinomontanum Nakai (Ranunculaceae) a perennial herbaceous flowering plant, is a widely used traditional Chinese medicine. Its rhizomes and roots are known as 'Gaowutou' in China, and it has been traditionally used for the treatment of rheumatoid arthritis, painful swelling of joints, bruises and injuries and has been known to grow well in regions of high altitude such as Gansu, Tibet etc. THE AIM OF THE REVIEW: This systematic review the comprehensive knowledge of the A. sinomontanum, including its traditional processing and uses, chemical constituents, pharmacological activities, toxicity assessment, pharmacokinetics and metabolism, and its use in clinical settings to emphasize the benefits of this species. We also discuss expectations for prospective research and implementation of this herb. This work lays a solid foundation for further development of A. sinomontanum.

MATERIALS AND METHOD

Information on the studies of A. sinomontanum was collected from scientific journals, books, and reports via library and electronic data search (PubMed, Elsevier, Scopus, Google Scholar, Springer, Science Direct, Wiley, ACS, EMBASE, Web of Science and CNKI). Meanwhile, it was also obtained from published works of material medica, folk records, ethnopharmacological literatures, Ph.D. and Masters dissertation.

RESULTS

As a member of the Ranunculaceae family, A. sinomontanum possesses its up-and-coming biological characteristics. It is widely reported for treating rheumatoid arthritis, painful swelling of joints, bruises and injuries. Currently, over 71 phytochemical ingredients have been obtained and identified from different parts of A. sinomontanum. Among them, alkaloids, flavonoids, steroids, glycosides are the major bioactive constituents. Activities such as antinociceptive, anti-inflammatory, antitumor, antiarrhythmic, local anesthetic, antipyretic, antimicrobial, insecticidal and others have been corroborated in vivo and in vitro. These properties are attributed to different alkaloids. In addition, many of the active ingredients, such as lappaconitine, ranaconitine and total alkaloids have been used as quality markers.

CONCLUSION

This work contributes to update the ethnopharmacological uses, chemical constituents, pharmacological activities, toxicity assessment, pharmacokinetics and metabolism, and clinical settings information for A. sinomontanum, which provide basic information to help better understand the pharmacological and toxicological activities of A. sinomontanum in human. However, further in-depth studies are needed to determine the medical uses of this herb and its chemical constituents, pharmacological activities, clinical applications and toxicology.

Neuronal Sprouting and Reorganization in Bone Tissue Infiltrated by Human Breast Cancer Cells

Background

Pain is a common complication for patients with metastatic bone disease. Animal models suggest that the pain, in part, is driven by pathological sprouting and reorganization of the nerve fibers innervating the bone. Here, we investigate how these findings translate to humans.

Methods

Bone biopsies were collected from healthy volunteers (n = 7) and patients with breast cancer and metastatic bone disease (permissions H-15000679, S-20180057 and S-20110112). Cancer-infiltrated biopsies were from patients without recent anticancer treatment (n = 10), patients with recent anticancer treatment (n = 10), and patients with joint replacement surgery (n = 9). Adjacent bone sections were stained for (1) protein gene product 9.5 and CD34, and (2) cytokeratin 7 and 19. Histomorphometry was used to estimate the area of bone marrow and tumor burden. Nerve profiles were counted, and the nerve profile density calculated. The location of each nerve profile within 25 μm of a vascular structure and/or cancer cells was determined.

Results

Cancer-infiltrated bone tissue demonstrated a significantly higher nerve profile density compared to healthy bone tissue. The percentage of nerve profiles found close to vascular structures was significantly lower in cancer-infiltrated bone tissue. No difference was found in the percentage of nerve profiles located close to cancer between the subgroups of cancer-infiltrated bone tissue. Interestingly, no correlation was found between nerve profile density and tumor burden.

Conclusions

Together, the increased nerve profile density and the decreased association of nerve profiles to vasculature strongly suggests that neuronal sprouting and reorganization occurs in human cancer-infiltrated bone tissue.

Medicinal Cannabis and Central Nervous System Disorders

Cannabinoids, including those found in cannabis, have shown promise as potential therapeutics for numerous health issues, including pathological pain and diseases that produce an impact on neurological processing and function. Thus, cannabis use for medicinal purposes has become accepted by a growing majority. However, clinical trials yielding satisfactory endpoints and unequivocal proof that medicinal cannabis should be considered a frontline therapeutic for most examined central nervous system indications remains largely elusive. Although cannabis contains over 100 + compounds, most preclinical and clinical research with well-controlled dosing and delivery methods utilize the various formulations of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), the two most abundant compounds in cannabis. These controlled dosing and delivery methods are in stark contrast to most clinical studies using whole plant cannabis products, as few clinical studies using whole plant cannabis profile the exact composition, including percentages of all compounds present within the studied product. This review will examine both preclinical and clinical evidence that supports or refutes the therapeutic utility of medicinal cannabis for the treatment of pathological pain, neurodegeneration, substance use disorders, as well as anxiety-related disorders. We will predominately focus on purified THC and CBD, as well as other compounds isolated from cannabis for the aforementioned reasons but will also include discussion over those studies where whole plant cannabis has been used. In this review we also consider the current challenges associated with the advancement of medicinal cannabis and its derived potential therapeutics into clinical applications.

Medicinal Cannabis and Central Nervous System Disorders

Cannabinoids, including those found in cannabis, have shown promise as potential therapeutics for numerous health issues, including pathological pain and diseases that produce an impact on neurological processing and function. Thus, cannabis use for medicinal purposes has become accepted by a growing majority. However, clinical trials yielding satisfactory endpoints and unequivocal proof that medicinal cannabis should be considered a frontline therapeutic for most examined central nervous system indications remains largely elusive. Although cannabis contains over 100 + compounds, most preclinical and clinical research with well-controlled dosing and delivery methods utilize the various formulations of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), the two most abundant compounds in cannabis. These controlled dosing and delivery methods are in stark contrast to most clinical studies using whole plant cannabis products, as few clinical studies using whole plant cannabis profile the exact composition, including percentages of all compounds present within the studied product. This review will examine both preclinical and clinical evidence that supports or refutes the therapeutic utility of medicinal cannabis for the treatment of pathological pain, neurodegeneration, substance use disorders, as well as anxiety-related disorders. We will predominately focus on purified THC and CBD, as well as other compounds isolated from cannabis for the aforementioned reasons but will also include discussion over those studies where whole plant cannabis has been used. In this review we also consider the current challenges associated with the advancement of medicinal cannabis and its derived potential therapeutics into clinical applications.

3-T magnetic resonance-guided high-intensity focused ultrasound (3 T-MR-HIFU) for the treatment of pain from bone metastases of solid tumors

INTRODUCTION

Bone metastases (BM) are still the main cause of morbidity and mortality in cancer patients, not only because of their complications, defined as skeletal-related events (SREs), but also because of the negative impact bone pain has on quality of life (QoL) and survival, especially when opioid analgesics and locoregional treatments fail.

MATERIALS AND METHODS

A single-center prospective study was carried out on 12 patients with symptomatic BM treated with MRI-guided focused ultrasound (MR-HIFU). The primary endpoint was the effectiveness of MR-HIFU in reducing current and breakthrough cancer pain (BTCP) scores. The main secondary aims were the evaluation of circulating markers at different time-points and their relation to pain and procedure efficacy. Other secondary objectives included temporal evolution of pain response, evaluation of QoL, and side effects of the treatment. Descriptive statistics were used to evaluate primary and secondary endpoints. Questionnaires on pain and QoL completed at baseline and at 30 days were compared using appropriate statistical tests with exploratory intent.

RESULTS

MR-HIFU was successfully completed in all 12 patients enrolled between September 2015 and December 2018. On day 30, 6 (50.0%) patients showed a complete response of current pain and 6 a partial response, while 5 (41.7%) obtained a complete BTCP response. A partial response of BM evaluated by MD Anderson criteria was obtained in 9 (81.8%) patients. Only one patient progressed in the target lesion after MR-HIFU. No treatment-related adverse events were recorded. Bone turnover markers CTX/RANK-L (P) do not demonstrate any significant change with the pain or BM response.

CONCLUSION

In our patients, targeted therapy of painful BM with MRI-guided focused ultrasound ablation was safe and showed encouraging early-onset and functional results.

The TRPA1 Channel Mediates Mechanical Allodynia and Thermal Hyperalgesia in a Rat Bone Cancer Pain Model

Background: Bone cancer pain (BCP) significantly affects patient quality of life, results in great bodily and emotional pain, and creates difficulties in follow-up treatment and normal life. Transient receptor potential ankyrin 1 (TRPA1) is an essential transduction ion channel related to neuropathic and inflammatory pain. However, the role of TRPA1 in BCP remains poorly understood. This study aimed to explore the relationship between TRPA1 and BCP.

Methods: A BCP model was induced by Walker256 cells to the left tibia. The sham group was induced by normal saline to the left tibia. Thereafter, pain behaviors and TRPA1 expression between the BCP group and the sham group were observed on the 14th day of modeling. The TRPA1 antagonist A967079 (10 mg/kg) was injected via tail vein. TRPA1 antisense oligodeoxynucleotide (AS-ODN, 5 nmol/10 μl) and missense oligodeoxynucleotide (MS-ODN, 5 nmol/10 μl) were intrathecally delivered via a mini-osmotic pump for 5 consecutive days to assess the effect of TRPA1 on BCP. Behavioral tests were assessed preoperatively and postoperatively. Real-time quantitative PCR and western blot analyses were used to measure TRPA1 levels among the different groups.

Results: The BCP model was successfully established via X-ray and pathological sections at 14 days. Compared to the sham group, the BCP group was more sensitive to mechanical stimuli, cool stimuli and hot stimuli. Intravenously injected A967079 can relieve paw mechanical withdrawal threshold and paw withdrawal thermal latency in rats with BCP. Moreover, AS-ODN can relieve paw mechanical withdrawal threshold and paw withdrawal thermal latency in rats with BCP. Additionally, relative mRNA and protein expression of TRPA1 in the BCP group were much higher than those in the sham group (14.55 ± 1.97 vs. 1 ± 0.04, P < 0.01). Compared to the BCP group, the relative mRNA and protein expression of TRPA1 in the BCP+AS-ODN group was reduced (14.55 ± 1.97 vs. 2.59 ± 0.34, P < 0.01).

Conclusions: The TRPA1 channel mediates mechanical allodynia and thermal hyperalgesia in a rat BCP model.

Using scaffolds as drug delivery systems to treat bone tumor

Surgery is the principal strategy to treat osteosarcoma and other types of bone tumors, but it causes bone defects that cannot be healed spontaneously. After surgery, patients still need to receive radiotherapy and/or chemotherapy to prevent tumor recurrence and metastasis, which leads to systemic side effects. Bone scaffolds exhibit the potentials to load cargos (drugs or growth factors) and act as drug delivery systems (DDSs) in the osteosarcoma postoperative treatment. This review introduces current types of bone scaffolds and highlights representative works using scaffolds as DDSs to treat osteosarcomas. Challenges and perspectives in the scaffold-based DDSs are also discussed. This review may provide references to develop effective and safe strategies for osteosarcoma postoperative treatment.