Angiogenesis-related cytokines, RANKL, and osteoprotegerin in multiple myeloma patients in relation to clinical features and response to treatment

The Clinical Relevance of Selected Cytokines in Newly Diagnosed Multiple Myeloma Patients

Multiple myeloma (MM) is the second most common hematological neoplasm. Cytokines, chemokines, and their receptors, induced by the microenvironment of MM, participate in tumor growth, the attraction of leukocytes, cell homing, and bone destruction. This study aimed to assess the correlation between the pretreatment serum concentrations of interleukin-6 (IL-6), interleukin-8 (IL-8), angiogenic chemokine monocyte chemoattractant protein-1 (MCP-1), and vascular endothelial growth factor (VEGF) and the clinical outcomes and survival of patients newly diagnosed with MM. The study group consisted of 82 individuals. The IL-8 concentration was significantly positively correlated with the age of onset (p = 0.007), the International Staging System (ISS) stage (p = 0.03), the Eastern Cooperative Oncology Group (ECOG) performance status (p < 0.001), the degree of anemia before treatment (p < 0.0001), the degree of kidney disease (p < 0.001), and VEGF (p = 0.0364). Chemotherapy responders had significantly lower concentrations of IL-8 (p < 0.001), IL-6 (p < 0.001), and VEGF (p = 0.04) compared with non-responders. Patients with treatment-induced polyneuropathy had significantly higher levels of IL-8 (p = 0.033). Patients with a high level of IL-6 had a 2-fold higher risk of progression-free survival (PFS) reduction (17 vs. 35 months; HR = 1.89; p = 0.0078), and a more than 2.5-fold higher risk of overall survival (OS) reduction (28 vs. 78 months; HR = 2.62; p < 0.001). High levels of IL-6, IL-8, and VEGF demonstrated significant predictive values for some clinical conditions or outcomes of newly diagnosed MM patients. Patients with an early response to chemotherapy had a significantly lower concentration of these cytokines. A high pretreatment IL-6 concentration was an independent negative prognostic marker for newly diagnosed MM patients.

The RANK-RANKL-OPG System: A Multifaceted Regulator of Homeostasis, Immunity, and Cancer

The RANK-RANKL-OPG system is a complex signaling pathway that plays a critical role in bone metabolism, mammary epithelial cell development, immune function, and cancer. RANKL is a ligand that binds to RANK, a receptor expressed on osteoclasts, dendritic cells, T cells, and other cells. RANKL signaling promotes osteoclast differentiation and activation, which leads to bone resorption. OPG is a decoy receptor that binds to RANKL and inhibits its signaling. In cancer cells, RANKL expression is often increased, which can lead to increased bone resorption and the development of bone metastases. RANKL-neutralizing antibodies, such as denosumab, have been shown to be effective in the treatment of skeletal-related events, including osteoporosis or bone metastases, and cancer. This review will provide a comprehensive overview of the functions of the RANK-RANKL-OPG system in bone metabolism, mammary epithelial cells, immune function, and cancer, together with the potential therapeutic implications of the RANK-RANKL pathway for cancer management.

Anti-Angiogenic Activity of Drugs in Multiple Myeloma

Angiogenesis represents a pivotal hallmark of multiple myeloma (MM) that correlates to patients’ prognosis, overall survival, and drug resistance. Hence, several anti-angiogenic drugs that directly target angiogenic cytokines (i.e., monoclonal antibodies, recombinant molecules) or their cognate receptors (i.e., tyrosine kinase inhibitors) have been developed. Additionally, many standard antimyeloma drugs currently used in clinical practice (i.e., immunomodulatory drugs, bisphosphonates, proteasome inhibitors, alkylating agents, glucocorticoids) show anti-angiogenic effects further supporting the importance of inhibiting angiogenesis from potentiating the antimyeloma activity. Here, we review the most important anti-angiogenic therapies used for the management of MM patients with a particular focus on their pharmacological profile and on their anti-angiogenic effect in vitro and in vivo. Despite the promising perspective, the direct targeting of angiogenic cytokines/receptors did not show a great efficacy in MM patients, suggesting the need to a deeper knowledge of the BM angiogenic niche for the design of novel multi-targeting anti-angiogenic therapies.

An Integrative Multi-Omics Analysis Reveals MicroRNA-143 as Potential Therapeutics to Attenuate Retinal Angiogenesis

Retinal neovascularization is a severe complication of proliferative diabetic retinopathy (PDR). MicroRNAs (miRNAs) are master regulators of gene expression that play an important role in retinal neovascularization. In this study, we show that miR-143-3p is significantly downregulated in the retina of a rat model of oxygen-induced retinopathy (OIR) by miRNA-sequencing. Intravitreal injection of synthetic miR-143 mimics significantly ameliorate retinal neovascularization in OIR rats. miR-143 is identified to be highly expressed in the neural retina particularly in the ganglion cell layer and retinal vasculature. In miR-143 treated cells, the functional evaluation showed a decrease in cell migration and delayed endothelial vessel-like tube remodeling. The multiomics analysis suggests that miR-143 negatively impacts endothelial cell activity through regulating cell-matrix adhesion and mediating hypoxia-inducible factor-1 signaling. We predict hub genes regulated by miR-143 that may be involved in mediating endothelial cell function by cytoHubba. We also demonstrate that the retinal neovascular membranes in patients with PDR principally consist of endothelial cells by CIBERSORTx. We then identify 2 hub genes, thrombospondin 1 and plasminogen activator inhibitor, direct targets of miR-143, that significantly altered in the PDR patients. These findings suggest that miR-143 appears to be essential for limiting endothelial cell-matrix adhesion, thus suppressing retinal neovascularization.

Association of RANK and RANKL gene polymorphism with survival and calcium levels in multiple myeloma

Multiple myeloma (MM) is a heterogeneous bone marrow cancer characterized by proliferation of malignant plasma cells in the bone marrow. One of its major symptoms are hypercalcaemia and bone lesions, which may result in pathologic bone fractures. Receptor activator for nuclear factor κB (RANK) and its ligand, RANKL, are part of an activation pathway for osteoclasts and are thus responsible for bone resorption. Furthermore, RANKL expression is increased in multiple myeloma. In the present study, we investigated the role of single nucleotide polymorphisms (SNPs) in the genes coding for RANK (rs1805034, rs8086340), RANKL (rs7325635, rs7988338), and TACI (rs34562254), a receptor for osteoclast-derived pro-survival factors. The study involved 222 patients and 222 healthy individuals, and the analysis included disease susceptibility, survival, bone lesions, calcium levels, and vascular endothelial growth factor levels. Patients with allele RANK rs1805034 C had higher survival (p = .003). This relationship was especially evident in women (p = .006). Furthermore, allele rs1805034 C was associated with slightly lower median age at diagnosis (64.0 vs. 65.5, p = .008). Allele RANKL rs7325635 A correlated with lower progression-free survival (p = .027), and with lack of early progression (p = .023). Additionally, women with allele rs7325635 G were found to have higher calcium blood concentration (p = .040). Allele TACI rs34562254 A was more common in MM patients in more advanced stages (II and III stage International Staging System) at diagnosis (p = .017), and the SNP showed a slight trend towards association in a multivariate analysis (p = .084). Taken together, our results suggest that RANK rs1805034 and RANKL rs7325635 may have a role in MM development and progression.

The HGF/Met/NF-κB Pathway Regulates RANKL Expression in Osteoblasts and Bone Marrow Stromal Cells

Multiple myeloma (MM)-induced bone disease occurs through hyperactivation of osteoclasts by several factors secreted by MM cells. MM cell-secreted factors induce osteoclast differentiation and activation via direct and indirect actions including enhanced expression of receptor activator of nuclear factor κB ligand (RANKL) in osteoblasts and bone marrow stromal cells (BMSCs). Hepatocyte growth factor (HGF) is elevated in MM patients and is associated with MM-induced bone disease, although the mechanism by which HGF promotes bone disease remains unclear. In the present study, we demonstrated that HGF induces RANKL expression in osteoblasts and BMSCs, and investigated the mechanism of induction. We found that HGF and MM cell supernatants induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. In addition, HGF increased phosphorylation of Met and nuclear factor κB (NF-κB) in ST2 cells, MC3T3-E1 cells, or mouse BMSCs. Moreover, Met and NF-κB inhibitors suppressed HGF-induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. These results indicated that HGF promotes RANKL expression in osteoblasts and BMSCs via the Met/NF-κB signaling pathway, and Met and NF-κB inhibitors suppressed HGF-induced RANKL expression. Our findings suggest that Met and NF-κB inhibitors are potentially useful in mitigating MM-induced bone disease in patients expressing high levels of HGF.

Cytokine profile in multiple myeloma

BACKGROUND

Cytokines play a crucial role in the growth, survival and dissemination of malignant plasma cells in patients of multiple myeloma (MM). We estimated concentrations of five key cytokines: Vascular Endothelial Growth Factor (VEGF), Interleukin-6 (IL-6), Tumor Necrosis Factor- alpha (TNF- α), B-cell activating factor (BAFF), and Receptor Activator of Nuclear Factor-κB ligand (RANKL) in newly diagnosed and relapsed/refractory MM (RRMM).

METHODS

The study groups include 68 newly diagnosed and 21 relapsed/refractory (RR) MM patients. 32 out of 68 newly diagnosed MM patients were evaluated for serum cytokine concentrations after their treatment. For survival analysis, the various parameters were studied in relation to both progression free survival (PFS) and overall survival (OS).

RESULTS

The median serum levels of VEGF, IL-6, BAFF and RANKL were higher in RRMM compared with newly diagnosed patients. However, the difference was significant for BAFF levels (p = 0.04). The median serum levels of VEGF, IL-6, TNF-α, BAFF and RANKL were significantly higher in newly diagnosed and RRMM patients, compared to controls. We also observed lower plasma levels of VEGF (p=<0.0001) and BAFF (p=<0.0001) in BM compartment compared to the levels in serum from peripheral blood of newly diagnosed patients. Significant reduction in the median levels of IL-6, TNF-α, BAFF and RANKL was seen after 4-6 cycles of induction treatment in responders but not in non-responders. On survival analysis, RRMM patients had inferior median OS and PFS compared to that in newly diagnosed MM patients and found to be significantly associated with low haemoglobin representing the more aggressive disease biology in recurrent myeloma. The mean levels of IL-6 were significantly different in patients who died as compared to patients who were alive.

CONCLUSIONS

The present study demonstrates that the serum levels of VEGF, IL-6, TNF, BAFF and RANKL are significantly elevated and decrease significantly after treatment. The concentrations of circulating cytokines will reflect those of the bone marrow and could be used for subsequent analyses.

Possible Prognostic Potential of RANKL and OPG in Metastatic Breast Cancer Egyptian Females

Objectives:

Searching for sensitive, minimally invasive biomarkers that represent tumor-associated changes in the peripheral blood might enable the early diagnosis of breast cancer (BC) and monitoring of tumor progression.

Methods:

Herein, we investigated the association of some circulating biomarkers with the risk of metastasis. In the current study, 115 BC patients which were subdivided into two groups: nonmetastatic breast cancer patients (NMBC) (n=83) and metastatic breast cancer patients (MBC) (n=32), and 79 apparently healthy controls were recruited. Serum protein levels of lysosomal protein transmembrane 4 beta (LAPTM4B), receptor activator of nuclear factor-kappa b (NF-Kb) ligand (RANKL), osteoprotegerin (OPG), vitamin D (VIT D), chitinase-3-like protein 1 (also known as YKL-40), and sirtuin 1 (SIRT1) were assessed in blood samples using ELISA technique.

Results:

The results showed that RANKL and OPG had the highest diagnostic potential for MBC detection, with area under the curve values of 0.97 and 0.94, respectively. Moreover, logistic regression analysis showed that RANKL had the highest differentiation power in the discrimination of MBC from NMBC.

Conclusion:

The study highlighted that measuring RANKL and OPG may be helpful in the early detection of metastasis in Egyptian patients with BC.

Role of the RANK/RANKL Pathway in Multiple Myeloma

Receptor activator of nuclear factor-kappa B (RANK) and its ligand, RANKL, are expressed in a variety of tissues throughout the body; their primary role is in the regulation of bone remodeling and development of the immune system. Consistent with these functions, evidence exists for a role of RANK/RANKL in all stages of tumorigenesis, from cell proliferation and carcinogenesis to epithelial-mesenchymal transition to neoangiogenesis and intravasation to metastasis to bone resorption and tumor growth in bone. Results from current studies also point to a role of RANK/RANKL signaling in patients with multiple myeloma, who have increased serum levels of soluble RANKL and an imbalance in RANKL and osteoprotegerin. Current therapies for patients with multiple myeloma demonstrate that RANKL may be released by tumor cells or osteoprogenitor cells. This article will review currently available evidence supporting a role for RANK/RANKL signaling in tumorigenesis, with a focus on patients with multiple myeloma.

Identification of genes and pathways related to lymphovascular invasion in breast cancer patients: A bioinformatics analysis of gene expression profiles

Surgery is the most effective treatment for breast cancer patients. However, some patients developed recurrence and distant metastasis after surgery. Adjuvant therapy is considered for high-risk patients depending on several prognostic markers, and lymphovascular invasion has become one of such prognostic markers that help physicians to identify the risk for distant metastasis and recurrence. However, the mechanism of lymphovascular invasion in breast cancer remains unknown. This study aims to unveil the genes and pathways that may involve in lymphovascular invasion in breast cancer. In total, 108 breast cancer samples were collected during surgery and microarray analysis was performed. Significance analysis of the microarrays and limma package for R were used to examine differentially expressed genes between lymphovascular invasion-positive and lymphovascular invasion-negative cases. Network and pathway analyses were mapped using the Ingenuity Pathway Analysis and the Database for Annotation, Visualization and Integrated Discovery. In total, 86 differentially expressed genes, including 37 downregulated genes and 49 upregulated genes were identified in lymphovascular invasion-positive patients. Among these genes, TNFSF11, IL6ST, and EPAS1 play important roles in cytokine-receptor interaction, which is the most enriched pathway related to lymphovascular invasion. Moreover, the results also suggested that an imbalance between extracellular matrix components and tumor micro-environment could induce lymphovascular invasion. Our study evaluated the underlying mechanisms of lymphovascular invasion, which may further help to assess the risk of breast cancer progression and identify potential targets of adjuvant treatment.

Erythropoietin treatment in murine multiple myeloma: immune gain and bone loss

Multiple myeloma (MM) is a plasma cell malignancy, characterized by osteolytic lesions and monoclonal immunoglobulins. The anemia, accompanying the disease is often treated with recombinant human EPO. Diverse non-erythropoietic effects of EPO have led us to question its combined action on the immune system and bone in the 5T33MM mouse model. EPO administration to MM mice attenuated disease progression as demonstrated by a decrease in serum MM IgG2b, splenic CD138 expressing cells, IL-6 and RORγτ transcripts in bone marrow (BM). IFN-γ transcript levels and macrophages (F4/80⁺CD11b⁺) in the BM both increased ~1.5 fold in the EPO-treated MM mice. In-vitro, EPO stimulated phagocytosis of 5T33MM cells (+30%) by BM-derived macrophages. In contrast, high-resolution microCT analysis of distal femurs revealed EPO-associated bone loss in both healthy and 5T33MM mice. EPO significantly increased expression of the osteoclastogenic nuclear factor-kappa B ligand (RANKL) in healthy mice, but not in MM mice, likely due to antagonizing effects on MM progression. Thus, in MM, EPO may act as a double-edged-sword stimulating immune response, while accelerating bone resorption, possibly via direct action on BM macrophages. This study supports a prudent approach of treating anemia in MM patients, aiming to maintain EPO-associated anti-MM effects, while considering bone damage.

Osteolytic lesions, cytogenetic features and bone marrow levels of cytokines and chemokines in multiple myeloma patients: Role of chemokine (C-C motif) ligand 20

The relationship between bone marrow (BM) cytokine and chemokine levels, cytogenetic profiles and skeletal involvement in multiple myeloma (MM) patients is not yet defined. This study investigated a cohort of 455 patients including monoclonal gammopathy of uncertain significance (MGUS), smoldering MM and symptomatic MM patients. Skeletal surveys, positron emission tomography (PET)/computerized tomography (CT) and magnetic resonance imaging (MRI) were used to identify myeloma bone disease. Significantly higher median BM levels of both C-C motif Ligand (CCL)3 and CCL20 were found in MM patients with radiographic evidence of osteolytic lesions as compared with those without, and in all MM patients with positive PET/CT scans. BM levels of CCL3, CCL20, Activin-A and Dickkopf-1 (DKK-1) were significantly higher in patients with high bone disease as compared with patients with low bone disease. Moreover, CCL20 BM levels were significant predictors of osteolysis on X-rays by multivariate logistic analysis. On the other hand, DKK-1 levels were related to the presence of MRI lesions independently of the osteolysis at the X-rays. Our data define the relationship between bone disease and the BM cytokine and chemokine patterns highlighting the tight relationship between CCL20 BM levels and osteolysis in MM.

Nuclear factor-kappa B ligand and osteoprotegerin levels in serum and gingival crevicular fluid in patients with bone metastases treated with zoledronic acid

Bone metastases are frequently observed in patients with certain types of cancer and are significant cause of morbidity. Zoledronic acid (ZA) is routinely prescribed for patients with bone metastases by affecting osteoclast function. We aimed to assess the effect of ZA over time in patients with bone metastases by analyzing novel bone turnover marker levels including receptor activator of nuclear factor-k B ligand (RANKL) and osteoprotegerin (OPG) in serum and gingival crevicular fluid (GCF). Also, associations between these bone turnover markers with hematological and biochemistry dysregulation were studied. The study enrolled patients with bone metastases including 32 patients diagnosed with solid tumors and 15 patients with multiple myeloma. In these patients, GCF and serum RANKL and OPG levels were measured and compared with measures of hematological and biochemical parameters before and after 3 months of ZA therapy. Mean subject age was 54 years old with a range of 28-80 years. Skeletal-related events were observed in 8.5% of all patients. After the 3-month treatment of ZA therapy, no significant differences were found in serum and GCF levels of RANKL and OPG when compared with before treatment levels. GCF RANKL levels at baseline and following 3 months of ZA therapy were significantly higher in patients with solid tumors when compared patients diagnosed with multiple myeloma (p=0.001; p<0.001, respectively). GCF OPG levels after the entire course of ZA therapy were greater in patients with 5 or more bone metastases (p=0.04). For patients with multiple myeloma, control GCF OPG was negatively correlated with control platelet and WBC counts (p=0.018 and p=0.027, respectively). A negative correlation was observed between control serum RANKL and control serum OPG levels in myeloma patients (p=0.001). After 3 months of ZA therapy, no significant differences were observed in GCF and serum RANKL and OPG levels when compared with baseline. A negative correlation was observed between serum control RANKL and OPG levels in myeloma patients. OPG levels were greater in patients with 5 or more bone metastases. In patients diagnosed with multiple myeloma, GCF OPG levels were negatively associated with WBC and platelet counts.

Angiogenesis and its therapeutic opportunities

Angiogenesis plays critical roles in human physiology that range from reproduction and fetal growth to wound healing and tissue repair. The sophisticated multistep process is tightly regulated in a spatial and temporal manner by "on-off switch signals" between angiogenic factors, extracellular matrix components, and endothelial cells. Uncontrolled angiogenesis may lead to several angiogenic disorders, including vascular insufficiency (myocardial or critical limb ischemia) and vascular overgrowth (hemangiomas, vascularized tumors, and retinopathies). Thus, numerous therapeutic opportunities can be envisaged through the successful understanding and subsequent manipulation of angiogenesis. Here, we review the clinical implications of angiogenesis and discuss pro- and antiangiogenic agents that offer potential therapy for cancer and other angiogenic diseases.

Bone metastases in gastric cancer follow a RANKL-independent mechanism

Gastric cancer is one of the most common and lethal malignancies worldwide. Bone metastases in gastric cancer are less common than in other solid tumors, but when they occur the prognosis is generally poor. Increased osteoclastogenesis and osteoclast activity are common features in bone metastases caused by different osteotropic cancer. We investigated osteoclastogenesis and its mechanisms in gastric cancer by enrolling 31 newly diagnosed gastric cancer patients and 45 healthy controls. We studied in vitro osteoclastogenesis in the peripheral blood mononuclear cell cultures of patients and controls, showing spontaneous osteoclastogenesis for half of the patients. This osteoclastogenesis was RANKL- and TNF-α-independent. We analyzed primary tumor and bone metastatic tissues of gastric cancer for the expression of genes involved in osteoclastogenesis. The expression of transforming growth factor-β (TGF-β), osteoprotegerin (OPG), IL-7 and dickkopf-1 (DKK-1) was higher in primary tumors than in bone metastases. RANKL was not detectable in primary tumor or in bone metastatic tissue. The serum RANKL level was significantly higher in healthy controls than in patients, and it was not related to osteoclastogenesis, thereby suggesting that RANKL is not involved in the bone metastatic mechanisms in gastric cancer. We hypothesized a role of RANKL in angiogenesis, thus we compared the serum levels of RANKL to those of VEGF, since VEGF is directly related to angiogenesis. Different from RANKL, the VEGF serum levels were higher in gastric patients than in controls, suggesting a block of the angiogenesis inhibition due to RANKL. RANKL and VEGF serum levels were not predictive of overall survival in our cohort of gastric patients.