Bone Metastases In Patients Research Articles

Melatonin Inhibits ET-1 Production to Break Crosstalk Between Prostate Cancer and Bone Cells: Implication for Osteoblastic Bone Metastasis Treatment.

Bone metastasis is the primary cause of death among patients with advanced prostate cancer (PCa). PCa tends to spread to bones and acquire the bone-like phenotype, causing osteoblastic bone metastasis. Unfortunately, there is no effective treatment for this condition. However, melatonin, which regulates our circadian rhythm, has been found to have anti-tumor properties. It has yet to be established whether it is effective in treating osteoblastic PCa metastasis. Our findings show that melatonin inhibits the production of endothelin-1 (ET-1) in osteoblastic PCa cells, suppressing osteoblast differentiation. Clinical results indicate that bone metastatic PCa patients have higher levels of ET-1 compared to nonmetastatic PCa patients. Furthermore, melatonin-induced miR-let-7f-5p inhibits ET-1-promoted osteoblast differentiation in osteoblastic PCa. Melatonin also suppresses the property of osteomimicry in osteoblastic PCa cells. Importantly, in the intratibia injection PCa metastasis model, melatonin decreased osteoblastic PCa tumor growth, inhibiting ET-1 production and osteoblast differentiation in vivo. Taken together, melatonin inhibits osteoblastic PCa-regulated osteoblastogenesis by reducing ET-1 production through upregulation of miR-let-7f-5p, while suppressing the property of osteomimicry in osteoblastic PCa. Melatonin therapy could be a promising approach to treating bone metastasis in osteoblastic PCa.

Prognostic Impact of Bone Metastasis in Patients With Metastatic Urothelial Carcinoma Treated With Durvalumab With or Without Tremelimumab in the DANUBE Study

Background and ObjectiveBone metastases (BM) in metastatic urothelial carcinoma (mUC) may impact patient outcomes, but their independent effect with immune checkpoint inhibitors (ICIs) is uncertain. We aimed to assess the impact of BM and PD-L1 status on outcomes in mUC patients treated with ICIs. MethodsThis post hoc analysis of the DANUBE study included 1032 mUC patients treated with durvalumab (D), D + tremelimumab (T), or standard chemotherapy (SoC). Patients were categorized by BM status and assessed for median overall survival (mOS) and median progression-free survival (mPFS) stratified by PD-L1 expression and treatment arm. Key Findings and LimitationsAmong all patients enrolled in the study, those with BM had a lower mOS than those with no BM (8.7 vs. 15.8 months; P < .0001). Patients with BM and high PD-L1 expression, treated with D or D + T, had numerically longer mOS than patients with BM and low PD-L1 expression. In contrast, in the chemotherapy arm, there was no difference in mOS for BM or no BM, based on PD-L1 expression. Patients with BM had shorter mPFS compared to no BM (2.6 vs. 5.4 months; P < .0001). The study is limited by its post hoc nature. Conclusions and Clinical ImplicationsPresence of BM was associated with worse outcomes across treatment arms. Patients with BM and high PD-L1 expression treated with D or D + T had longer mOS, suggesting potential benefits of ICIs in this subgroup. Consideration of BM and PD-L1 status in treatment decisions for mUC patients receiving ICIs may improve clinical outcomes. Plain English SummaryWe investigated the impact of bone metastases in patients with advanced bladder cancer treated with immune therapy. Patients with bone metastases had shorter survival times compared to those without. However, patients with high levels of a specific marker in their tumors had better outcomes with immune therapy. Understanding these factors could help doctors make better treatment decisions for patients with bladder cancer.

Bioinformatic prediction of miR-320a as a potential negative regulator of CDGSH iron-sulfur domain 2 (CISD2), involved in lung adenocarcinoma bone metastasis via MYC activation, and associated with tumor immune infiltration.

Ferroptosis, a form of regulated cell death associated with iron-dependent lipid peroxidation, plays a role in cancer progression. However, the specific mechanisms of ferroptosis in lung adenocarcinoma (LUAD) bone metastasis (BM) remain unclear. Using bioinformatics analysis, this study sought to identify the ferroptosis-associated genes involved in BM in LUAD, thus providing potential novel targets for the treatment of BM in LUAD. The RNA expression dataset GSE10799 was acquired from the Gene Expression Omnibus (GEO) database, and intersected with the ferroptosis dataset to identify ferroptosis-related differentially expressed genes (DEGs). The expression of candidate genes and their correlation with the prognosis of LUAD patients were validated in The Cancer Genome Atlas (TCGA) database. A protein gene interaction network was constructed using GeneMania and Retrieval of Interacting Genes/Proteins (STRING) databases. The association between the candidate genes and immune cells was assessed via TCGA and Tumor IMmune Estimation Resource (TIMER) databases. The potential mechanisms were elucidated by a gene set enrichment analysis (GSEA). The relevant microRNAs (miRNAs or miRs) that bind to the 3'untranslated region (3'UTR) end of candidate genes' mRNA was explored using the TargetScan database. The expression of these candidate miRNAs in LUAD was validated and the correlation between candidate miRNAs and candidate mRNAs was tested using the TCGA database. Finally, the clinical data of 40 LUAD patients were retrospectively analyzed to evaluate the clinical value of candidate gene expression for LUAD BM patients. In this research, 15 ferroptosis-related DEGs in LUAD BM were identified. TCGA database analysis indicated that patients with low levels of CDGSH iron-sulfur domain 2 (CISD2) in LUAD had better disease-specific survival (DSS), overall survival (OS), and a better progression-free interval (PFI) than those with high levels of CISD2. The TIMER database results show that the expression of CISD2 is correlated with the infiltration levels of various immune cells. The GSEA indicated that CISD2 might influence biological activity in LUAD by participating in cell-cycle regulation, mitochondrial translation, DNA damage repair, c-Myc (MYC) activation, and the P53 signaling pathway. Through the combined analysis of the TargetScan and TCGA databases, hsa-miR-320a was identified as the optimal upstream regulatory miRNA. The immunohistochemistry data indicated that the positive CISD2 expression rates and immunohistochemistry scores of the patients with BM were significantly higher than those of the patients without BM (P<0.05). The high expression of CISD2 is a significant risk factor for BM in LUAD. The downregulation of CISD2 expression may extend DSS, OS, and the PFI of LUAD patients. Thus, CISD2 could serve as a novel predictive biomarker for LUAD patients. Further, miR-320a might negatively regulate CISD2 and participate in LUAD BM by activating MYC. These data provide a potential perspective for developing anticancer therapies for LUAD-BM patients.

The HOXC10/NOD1/ERK axis drives osteolytic bone metastasis of pan-KRAS-mutant lung cancer

While KRAS mutation is the leading cause of low survival rates in lung cancer bone metastasis patients, effective treatments are still lacking. Here, we identified homeobox C10 (HOXC10) as a lynchpin in pan-KRAS-mutant lung cancer bone metastasis. Through RNA-seq approach and patient tissue studies, we demonstrated that HOXC10 expression was dramatically increased. Genetic depletion of HOXC10 preferentially impeded cell proliferation and migration in vitro. The bioluminescence imaging and micro-CT results demonstrated that inhibition of HOXC10 significantly reduced bone metastasis of KRAS-mutant lung cancer in vivo. Mechanistically, the transcription factor HOXC10 activated NOD1/ERK signaling pathway to reprogram epithelial-mesenchymal transition (EMT) and bone microenvironment by activating the NOD1 promoter. Strikingly, inhibition of HOXC10 in combination with STAT3 inhibitor was effective against KRAS-mutant lung cancer bone metastasis by triggering ferroptosis. Taken together, these findings reveal that HOXC10 effectively alleviates pan-KRAS-mutant lung cancer with bone metastasis in the NOD1/ERK axis-dependent manner, and support further development of an effective combinatorial strategy for this kind of disease.

IASLC grading system predicts distant metastases for resected lung adenocarcinoma

AimsThe International Association for the Study of Lung Cancer (IASLC) has proposed a new histological grading system for invasive lung adenocarcinoma (LUAD). However, the efficacy of this grading system in...

Low molecular weight 35 kDa hyaluronan fragment HA35 in the treatment of bone metastasis pain: A case report.

Late-stage cancer patients often experience severe pain due to bone metastasis, caused by structural damage and cancer-induced inflammation. Hyaluronan, known to alleviate pain by blocking the TRVP1 calcium channel, faces limitations due to its high molecular weight. However, 35 kDa low molecular weight hyaluronan fragment (HA35) have shown promise in relieving various pains, including cancer-related pain. Nonetheless, evidence regarding their efficacy in bone metastasis pain remains scarce. A 52-year-old female with a rectal malignant tumor and multiple secondary tumors in the sacrum and lungs, accompanied by bone metastasis pain. Despite undergoing radiotherapy, her pain relief was unsatisfactory. Before treatment with HA35, her numerical rating scale score was 10, severely affecting her sleep, appetite, and daily activities. The patient was diagnosed with rectal malignant tumor with multiple metastases, presenting symptoms such as sacral metastasis pain, anal pain, lower limb pain, and anterior abdominal pain. Sacral metastasis pain and lower limb pain indicated a clear diagnosis of bone metastasis pain. Treatment involved subcutaneous injection into the deep fat tissue layer of the abdomen. A subcutaneous injection of 100 mg/5 mL of HA35 was administered once into the deep fat tissue of the abdomen, with subsequent injections repeated every 3 days. Following 1 injection, the patient's pain score decreased to 6 points within 20 minutes, providing 40% pain relief. After 40 minutes, the score further dropped to 4 points, with 60% pain relief. After 50 injections, pain was consistently controlled at around 3 points. Subcutaneous injection of HA35 into the abdominal fat tissue effectively alleviates pain in cancer and bone metastasis patients resistant to conventional treatments. Additionally, it helps alleviate anxiety and fatigue, and improves diet and sleep, thereby offering crucial palliative care for advanced cancer patients.

A phase Ib study of JMT103, a receptor activator of NF-kB ligand (RANKL) antibody, in patients (pts) with bone metastases from solid tumors.

e15190 Background: JMT103 is a human IgG4 monoclonal antibody against RANKL and blocks the RANK signaling in osteoclasts, thus suppressing bone resorption. This phase Ib study aims to demonstrate the activity of JMT103 in bone metastases patients with solid tumors. Methods: In this randomized, multi-center, open-label, phase Ib study, adult pts with bone metastases from solid tumors were enrolled and randomized at a 1:1:1 ratio to receive JMT103 subcutaneously at 120mg every 4 weeks (Q4W, Cohort 1), 120mg every 8 weeks (Q8W, Cohort 2) and 180mg Q8W (Cohort 3) up to 49 weeks. The primary endpoint was the percent change from baseline to week 13 in creatinine-adjusted urinary N-telopeptide (uNTx/Cr). Secondary endpoints included safety, anti-drug antibodies (ADA) positivity, the percentage of patients who experienced on-study skeletal-related events (SREs), and ≥ 2-point decreases in pain with Brief Pain Inventory – Short Form. Results: At database lock (Mar. 31, 2023), 295 pts were enrolled; 293 were treated with JMT103 and eligible for efficacy and safety evaluation (96 pts in Cohort 1, 97 pts in Cohort 2, and 100 pts in Cohort 3). The median age was 58 years (Interquartile range [IQR] 51, 66), and the primary tumor types were mainly breast (145, 50%) and prostate cancer (44, 15%). At week 13, the median (IQR) percent change in uNTx/Cr was - 80% (- 93%, - 50%) in Cohort 1, - 73% (- 94%, - 34%) in Cohort 2, and - 76% (- 92%, - 40%) in Cohort 3, respectively. The incidence of SREs in the three cohorts was 3%, 6%, and 7%, respectively. Among the 33 pts in Cohort 1, 35 pts in Cohort 2, and 37 pts in Cohort 3 with baseline pain scores ≥ 2, 61% in Cohort 1, 46% in Cohort 2, and 54% in Cohort 3 experienced ≥ 2-point decreases in pain at the first post-treatment visit (Day 15). For ADA analysis, only 1 (1%) pt in Cohort 2 with a negative result at baseline tested positive after treatment. The table shows the overall summary of the safety profile. Most of TRAEs were low in grade and resolved quickly. The most common TRAEs (any grade) were hypocalcemia (68, 23%), hypophosphatemia (67, 23%), and increased aspartate transaminase (35, 12%). Among the 40 cases of grade-5 TEAE, only 1 was reported as a TRAE (pneumonia); the rest were unrelated to JMT103. Conclusions: Our study demonstrated a promising efficacy of JMT103 in reducing bone metabolism biomarker and a good safety profile with low immunogenicity. Clinical trial information: NCT04630522 . [Table: see text]

Using machine learning approach based on gene expression profiling to predict the risk of bone metastasis in lung cancer.

e20522 Background: Bone metastasis (BM) occurs in about 30% of patients with advanced lung cancer, and the prognosis of BM patients is very poor, with a median survival of 6-10 months. Therefore, we attempted to use machine learning methods based on gene expression profiles to construct a model to predict BM. Methods: Gene Expression Omnibus (GEO) database were searched, then these datasets (GSE10096, GSE29367, GSE29391, GSE76194, GSE175601) were included for analysis. Batch effects were removed using the ComBat function from the R package sva (v3.44.0). edgeR was used for differential expression analysis, and genes that had an absolute log2 fold change &gt; 1 and adjusted p-value &lt; 0.05, were selected as differentially expressed genes (DEGs) for modeling. Random forest (RF) modeling was performed using the R package random Forest (v4.7-1.1), and support vector machine (SVM) modeling and SVM Recursive Feature Elimination (SVM-RFE) were performed using the R package e1071 (v1.7-13). Survival curves were generated using the GEPIA2 R packages. Models performance was evaluated using the area under the receiver operating characteristics curve (AUC). Results: A total of 48 qualified cases were subjected to analysis, including 22 BM and 26 non-BM patients. Differential expression analysis revealed that a total of 327 DEGs were identified in the BM group. We divided the sample dataset into a training set and a test set. In the first approach, we attempted to use all 327 DEGs features to train the models. Among the evaluated models, the RF algorithm performed best with an AUC of 0.753, while the SVM algorithm had an AUC of 0.938. The second approach, we applied the SVM-RFE algorithm for feature selection, which ranked the features according to their importance, and the top 10 genes/features (TMC5, S100A4, EEF1A2, CLDN1, RALY, MYH10, MAGEC2, ALDH1A1, PI3, SALL1) were used to build a classification model (in the test set, sensitivity was100%, specificity: 81.8%, AUC:0.909). In addition, TCGA survival analysis of 10 genes was performed and found that the expression levels of five genes, including ALDH1A1, MYH10, RALY, CLDN1 and MAGEC2, were significantly associated with prognosis (p &lt; 0.1). Conclusions: Our study suggests that we have identified ten key genes associated with BM of lung cancer which could be potential therapeutic targets.

Abstract PO5-05-12: Loco-regional Treatment in De Novo Bone Only Metastatic Breast Cancer; Prospective, Multi-Institutional Real-World Data, BOMETIN, Protocol MF14-1a

Abstract Introduction: The impact of loco-regional treatment (LRT) on survival in de novo bone-only metastatic breast cancer (BC) is controversial. The aim of this study is to assess the effect of LRT on survival utilizing international, prospectively acquired data in this cohort of patients. Materials and Methods: Patients with de novo metastatic BC with bone-only metastases were divided into two groups: those receiving systemic therapy only (ST) and those undergoing LRT. Patients who received LRT were divided into two groups: those who received ST after LRT (LRT+ST arm) and those who received ST prior to LRT (ST+LRT arm). Solitary or multiple bone metastases were classified, and factors associated with disease progression were analyzed. Results: There were a total of 744 patients with de novo bone-only metastatic BC treated at each of the participating institutions between 2014 and 2022, with 372 (50%) participants in each arm. Median follow-up was 48 months (32-66, 25-75%). Patients in the LRT group were significantly younger than the ST group [50 (42, 60) vs 55 (44, 66), p=0.0001]. There were no significant differences in grade, Her2 neu and triple negative status, receipt of hormonal therapy and intervention to metastatic sites. During follow-up, 58% (n=217) of patients in ST arm and 32% (n=120) of patients in LRT arm died (p&amp;lt; 0.001). Local progression was observed in 20% of the patients in the ST arm whereas it was 9% in the LRT arm (p=0.0001). Systemic progression occurred more in ST arm; 66% (n=244) compared to 41% (n=152) of patients in LRT group (p&amp;lt; 0.001). The Hazard of death was 64% lower in LRT group than in ST group (HR: 0.36, 95% CI: 0.29-0.45), p&amp;lt;0.0001). The burden of metastatic disease was significantly different between groups with the solitary bone metastasis rate higher in LRT group than the ST only group (50% vs 24%, p&amp;lt; 0.001). However, the LRT group had better overall survival for both solitary (HR: 0.38, 95% Cl: 0.26-0.55) and multiple (HR: 0.38, 95% Cl: 0.29-0.51) bone metastases patients. Within the LRT group, survival rates were similar whether the breast surgery was performed before or after ST.Multivariate Cox analysis showed that LRT and ER/PR positivity significantly decrease the hazard of death (p&amp;lt; 0.05). Conclusion: Analysis of this large multi-institutional patient cohort provides further evidence that LRT improves overall survival and lowers loco-regional recurrence in patients with de novo bone-only metastatic BC. In breast cancer patients with bone-only metastases at presentation, the decision for LRT should be made through a multidisciplinary approach with consideration of surgical therapy at the primary tumor. Citation Format: Atilla Soran, Serdar Ozbas, Lutfi Dogan, Didem Can Trabulus, Jamila El-Azrhi, Kazim Senol, Berk Goktepe, Shruti Zaveri, Salyna Meas, Umut Demirci, Hasan Karanlik, Aykut Soyder, Ahmet Dağ, Ahmet Bilici, Mutlu Dogan, Mehmet Ali Nahit Sendur, Hande Koksal, Mehmet Ali Gulcelik, Neslihan Cabıoğlu, Levent Yeniay, N. Zafer Utkan, Nuri Karadurmus, Gul Daglar, Turgay Simsek, Birol Yildiz, Cihan Uras, Mustafa Tukenmez, Cihangir Ozaslan, Niyazi Karaman, Arda Isik, Berkay Demirors, Efe Sezgin, Vahit Ozmen, Anthony Lucci. Loco-regional Treatment in De Novo Bone Only Metastatic Breast Cancer; Prospective, Multi-Institutional Real-World Data, BOMETIN, Protocol MF14-1a [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-05-12.

Navigating through the coordination preferences of heavy alkaline earth metals: Laying the foundations for 223Ra- and 131/135mBa-based targeted alpha therapy and theranostics of cancer

The clinical success of [223Ra]RaCl2 (Xofigo®) for the palliative treatment of bone metastases in patients with prostate cancer has highlighted the therapeutic potential of α-particle emission. Expanding the applicability of radium-223 in Targeted Alpha Therapy of non-osseous tumors is followed up with significant interest, as it holds the potential to unveil novel treatment options in the comprehensive management of cancer. Moreover, the use of barium radionuclides, like barium-131 and -135m, is still unfamiliar in nuclear medicine applications, although they can be considered as radium-223 surrogates for imaging purposes. Enabling these applications requires the establishment of chelators able to form stable complexes with radium and barium radionuclides. Until now, only a limited number of ligands have been suggested and these molecules have been primarily inspired by existing structures known for their ability to complex large metal cations. However, a systematic inspection of chelators specifically tailored to Ra2+ and Ba2+ has yet to be conducted.This work delves into a comprehensive investigation of a series of small organic ligands, aiming to unveil the coordination preferences of both radium-223 and barium-131/135m. Electronic binding energies of both metal cations to each ligand were theoretically computed via Density Functional Theory calculations (COSMO-ZORA-PBE-D3/TZ2P), while thermodynamic stability constants were experimentally determined for Ba2+-ligand complexes by potentiometry, NMR and UV–Vis spectroscopies. The outcomes revealed malonate, 2-hydroxypyridine 1-oxide and picolinate as the most favorable building blocks to design multidentate chelators. These findings serve as foundation guidelines, propelling the development of cutting-edge radium-223- and barium-131/135m-based radiopharmaceuticals for Targeted Alpha Therapy and theranostics of cancer.

Simultaneous assessment of renal function with hybrid SPECT/CT during whole-body bonescintigraphy (WbBS) in patients with prostate carcinoma (PC) and concomitant urological diseases with impaired renal drainage

Introduction: Whole-body bone scintigraphy (WbBS) is the „gold standard“ worldwide for early detection and evaluation of treatment of bone metastatic tumors, incl.PC.Due to the known renal excretion of the osteotropic RPh – 99mTc-methylene diphosphonate (99mTc-MDP), it is possible to perform an „early“ assessment of renal function, followed by a „late“ standard WbBS with SPECT/CT. Aim: The aim of the present study was to evaluate and indicate the diagnostic utility of a single administration of 99mTc-MDP with a dual protocol implemented in the CNM for sequential scintigraphic assessment of renal function and early detection, staging and evaluation of the treatment effect of bone metastases in patients with PCand concomitant urological diseases. Materials and methods: We present three patients with PC, referred for restaging of the oncological disease and performing WbBS in the CNM in USHATO, Sofia, Bulgaria. According to the indications and assessment of a nuclear medicine physician, a one-day protocol was carried out and introduced in the CNM, starting with dynamic renal scintigraphy (DRS) at the time of bo-lus i.v.injection of 99mTc-MDP and subsequent after the 2nd hour planar WbBS with hybrid target or wholebody SPECT/CT scan. Results: The first patient is with metastatic PC after complex treatment.Due to elevated levels of creatinine, „early“ DRS and „late“ restaging WbBS were performed, with reported full therapeutic effect of bone-metastatic disease and isosthenuric changes in right kidney, but with altered secretory-excretory phases and reduced total GFR.The second case is a patient with high-risk CP, who underwent hormonal and definitive radiation therapy, with episodes of renal colic. DRS revealed a hydronephrotic type nephrogram on the right, and a subsequent CT scan showed osteoporotic compression fractures of two vertebrae, without bon metastasis. An additional SPECT/CT finding is a calcium-dense calculus as a probable cause of the hydronephrotic changes. The third patient, is with high-risk CP and undergonetreatment. Initial DRSshowed secretory-excretory dysfunction of the right kidney with retention in the pyelocaliceal system. SubsequentWbBSand SPECT/CT revealed a complete therapeutic effect of a solitary bony lesion in the 6th right rib and malrotation of the right kidney with a staghorn calculus in the pyelon. All patients are referred for urological control. Conclusion: DRS performed with hybrid SPECT/ CT, in the course of routine WbBS, for re-staging of patients with CP, gives along with bone metastatic follow-up, valuable functional information about the separated renal function, drainage and morphological guidance for pathological changes from concomitant urological diseases.

Surgical Resection of Primary Tumor for Bone Metastatic Breast Cancer Patients at Initial Presentation.

The purpose of this study was to investigate whether primary tumor resection in patients with bone metastatic breast cancer has an impact on survival using the Surveillance, Epidemiology, and End Results database, considering subtype classification. We included all female patients with bone metastatic breast cancer at initial presentation between 2010 and 2016 with known hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) statuses. Cases showing unknown cause of death or unknown HR/HER2 status were excluded. Survival analysis was performed using Cox proportional hazards modeling to calculate hazard ratios (HZR). Of the 13,450 patients included in this study, 2,073 patients were HR+/HER2+, 8,597 patients were HR+/HER2-, 797 patients were HR-/HER2+, and 1,182 patients were HR-/HER2- (triple-negative). Five-year overall survival (OS) rate was 34.5% in HR+/HER2+, 26.0% in HR+/HER2-, 29.2% in HR-/HER2+ and 8.0% in triple-negative. Triple-negative patients showed the worsen OS [HR+/HER2+: HZR=2.1, 95% confidence interval (CI)=1.9-2.3; HR+/HER2-: HZR= 2.4, 95%CI=2.2-2.6; HR-/HER2+: HZR=1.5, 95%CI=1.3-1.6]. After excluding patients who died within six months, primary tumor resection prolonged survival in each subtype classification except HR-/HER2+. Patients with triple-negative bone metastatic breast cancer showed unfavorable survival. Primary tumor resection prolonged survival in each subtype except for HR-/HER2+.

Comparison of the relative diagnostic performance of 68Ga-DOTA-IBA and 18F-NaF for the detection of bone metastasis.

We aimed to compare the relative diagnostic efficacy of 68Ga-Labeled DOTA-ibandronic acid (68Ga-DOTA-IBA) to that of18F-NaF PET/CT as a mean of detecting bone metastases in patients with a range of cancer types. This study retrospectively enrolled patients with bone metastases associated with various underlying malignancies. All patients underwent both 68Ga-DOTA-IBA and 18F-NaF PET/CT scans. Histopathology and follow-up CT or MRI imaging results were used as reference criteria, with a minimum follow-up period of 3 months. The maximum Standardized Uptake Value (SUVmax) and number of bone metastases were recorded. The Target-Background Ratio (TBR) was calculated along with the detection rate, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 68Ga-DOTA-IBA and 18F-NaF PET/CT imaging for overall and partial primary solid tumor bone metastases. Pearson chi-square test, McNemar test, and Kappa test was conducted to assess the correlation and consistency of diagnostic efficiency between the two imaging agents. Receiver Operating Characteristic curve (ROC curve) was performed to compare diagnostic performance and the area under the curve of the two imaging agents, determining optimal critical values for SUVmax and TBR in diagnosing bone metastasis. Differences in SUVmax and TBR values between the two imaging agents for detecting bone metastases were analyzed using the Wilcoxon signed rank test. The difference was statistically significant when P < 0.05. A total of 24 patients (13 women and 11 men) were included in this study, with a mean age of 52 (interquartile range, 49-64 years). The detection rate, sensitivity, specificity, PPV, NPV, accuracy, and AUC of 68Ga-DOTA-IBA and 18F-NaF PET/CT for bone metastases were 81%, 90%, 62%, 95%, 43%, 88%, 0.763, and 89%, 99%, 59%, 95%, 89%, 95%, 0.789, respectively. There was no significant difference between the two imaging methods (P < 0.01), and there was a significant correlation (X2=168.43, P < 0.001) and a strong consistency (Kappa=0.774,P < 0.001) between the diagnostic results of the two imaging agents. The SUVmax values of lesions measured by 68Ga-DOTA-IBA and 18F-NaF imaging in 22 patients with bone metastasis were 5.1 ± 5.4 and 19.6 ± 15.1, respectively, with statistically significant differences (P<0.05). The TBR values of the two imaging methods were 5.0 ± 5.0 and 6.7 ± 6.4, respectively, with statistically significant differences (P<0.05). The AUC of the SUVmax of 68Ga-DOTA-IBA and 18F-NaF curves were 0.824 and 0.862, respectively, with no statistically significant difference (P=0.490). No significant difference was found in the AUC of the TBR of 68Ga-DOTA-IBA and 18F-NaF (0.832 vs 0.890; P=0.248). Subgroup analysis showed significant correlation between the two imaging agents in the diagnosis of bone metastases in lung cancer and breast cancer, with consistent diagnostic results. However, in the diagnosis of bone metastases in prostate cancer, there was a significant difference (P<0.001) and lack of consistency (P=0.109). The diagnostic efficacy of 68Ga-DOTA-IBA for bone metastasis lesions is comparable to that of 18F-NaF. This finding holds significant clinical importance in terms of diagnosis of bone metastasis and selecting treatment plans for patients with malignant tumors.

Abstract 3782: IASLC grading system predict distant metastases for resected lung adenocarcinoma

Abstract The International Association for the Study of Lung Cancer (IASLC) proposed a new histological grading system for invasive lung adenocarcinoma (LUAD). However, whether this new grading system is able to predict distant metastases in LUAD patients has not been evaluated. This study investigated the feasibility of using this grading system to predict the occurrence of brain and bone metastases in patients with resectable LUAD which identifies patients who have a high probability of developing distant metastases after surgery. We collected clinical information and pathological reports of 179 early stage LUAD patients who underwent resection during 2008 to 2015 from Wake Forest Comprehensive Cancer Center. All patients were followed up for 5 years and both bone and brain metastasis-free survival were calculated. Tumor grading of all samples was evaluated by both IASLC grading and predominant pattern-based grading systems. The ability of predicting distant metastases using IASLC grading and tumor stage were examined by receiver operating characteristic curves (ROC). 28 out of 179 patients developed distant metastases in five years with a median overall survival of 60 months for metastasis-free patients and 38.9 for patients with distant metastasis. Compared to predominant pattern-based grading system, IASLC grading system showed a stronger correlation with distant metastasis incidence. Complex gland pattern is enriched in patients who developed bone and brain metastases compared to metastasis-free patients. IASLC grading system also showed a superior prediction power of distant metastasis compared to tumor stage with area under curve (AUC) of 0.69 for brain metastasis and 0.71 for bone metastasis. IASLC grading system is capable of predicting the incidence of distant metastasis among early-stage invasive LUAD patients. Citation Format: Yuezhu Wang, Margaret R. Smith, Yin Liu, Mary E. Green, Omer A. Hassan, Alexandra M. Balmaceda, Tammy Sexton, Wencheng Li, Fei Xing. IASLC grading system predict distant metastases for resected lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3782.

Abstract 2815: Immunotherapy development landscape for bone metastasis - need of predictive preclinical efficacy evaluation for de-risking clinical development

Abstract Most cancer deaths are due to metastases, and bone metastases are challenge especially in breast and prostate cancer, being developed in 70-90% of advanced-stage patients. Bone metastases remain incurable causing high mortality, skeletal-related effects and decreased quality of life. Currently used immunotherapies are ineffective in bone metastases. This creates a need to improve understanding immune microenvironment in bone metastases, namely interactions between tumor, immune and bone cells according to the osteoimmuno-oncology (OIO) concept, and ultimately to develop immunotherapies that primarily target bone metastases. We used 1stOncology database, a cancer drug development resource to identify novel immunotherapies in development for breast and prostate cancer bone metastasis. Twenty-four immunotherapies that included evaluation of effects on bone metastasis were identified. Efficacy of only three of the identified therapies had been evaluated in preclinical bone metastasis models, one reason being that such models have not been commonly available. The use of clinically relevant and predictive preclinical bone metastasis models would significantly de-risk decision making when moving to clinical development in bone metastasizing cancers. To support predictive preclinical evaluation of immunotherapies for bone metastatic cancers, we describe a preclinical bone metastasis technology platform for evaluating efficacy of immunotherapies. The platform utilizes tumors growing in bone microenvironment, mimicking growth of bone metastases in patients, and generates tumor-induced bone effects in a cancer-type specific manner. Syngeneic and/or humanized mouse models with tumor and immune cells of the same species are needed for development of immunotherapies, allowing interactions of tumor and immune cells in the bone metastatic microenvironment to support mode-of-action studies. The platform is clinically predictive, as demonstrated with observed effects that align with clinical findings. As an example, anti-PD-1 antibody had no effects on breast and prostate cancer bone metastases, predicting recent clinical findings that demonstrate lack of efficacy in clinical prostate cancer trials. We conclude that tumor microenvironment in bone metastases has unique characteristics and is understudied as a potential primary cause of lack of efficacy of many immunotherapies, especially in breast and prostate cancer. It is prime time to focus on bone metastases by increasing understanding of the immune landscape in the bone tumor microenvironment according to the OIO concept. The biologically relevant and clinically predictive preclinical bone metastasis technology platform should be routinely used to study the mechanism-of-action and efficacy of therapies before entering clinical development in bone metastasizing cancers. Citation Format: Tiina E. Kähkönen, Jussi M. Halleen, Gary MacRitchie, Ronnie M. Andersson, Jenni Bernoulli. Immunotherapy development landscape for bone metastasis - need of predictive preclinical efficacy evaluation for de-risking clinical development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2815.

Abstract 6866: Investigating the role of Epha2 in breast cancer-mediated myeloid cell expansion and function

Abstract Bone metastases are present in over 70% of metastatic breast cancer patients, and current therapy reduces osteolysis in tumor-induced bone disease (TIBD) but does not improve overall survival. Frequently, TIBD is characterized by an increase in osteoclast proliferation and bone-resorbing activity, and patients often experience pain and pathologic fractures. Increased bone resorption releases growth factors that aid in the progression of tumor growth causing the ‘vicious cycle’. Additionally, bone metastatic patients are often resistant to first- and second-line therapies highlighting an importance for research in this area. The receptor tyrosine kinase, Ephrin-type-A 2 receptor (EphA2), participates in both forward and reverse signaling during receptor/ligand engagement and participates in many physiological and pathological processes, including bone homeostasis, immunity, and cancer. Interestingly, EphA2 is highly expressed in bone metastases, and previous evidence suggests that EphA2 can promote TIBD and reduce anti-tumor immunity. We therefore hypothesize that increased expression of EphA2 in breast cancer cells at the site of bone metastasis promotes expansion of myeloid cells, leading to TIBD. Previous data shows a reduction in osteoclast number and bone lesions following EphA2 knockout. However, the mechanism by which EphA2 mediates the expansion of osteoclasts is not well understood. In agreement with previous work, our data shows that EphA2 deletion in murine breast cancer (BC) cell line, 4T1, reduces bone lesion area and number and the presence of bone metastasis-associated macrophages. Additionally, we observed a significant reduction in Ly6Chi cells. To assess the effects of EphA2 deletion on the behavior of 4T1 cells, we conducted a wound healing assay and observed a decrease in wound healing capacity in 4T1 cells following EphA2 deletion. This suggests that EphA2 expression in 4T1 cells may increase their metastatic potential. We will repeat these studies and incorporate factors from the bone marrow. Our future studies will investigate the role of EphA2 signaling and reverse signaling in BC cell lines, myeloid progenitor cells, osteoclasts, and bone metastasis-associated macrophages. We will utilize murine and human BC cell lines to elucidate the effects of EphA2 deletion in BC on immune cell populations, bone metastasis, and tumor progression. Additionally, we will investigate how EphA2 reverse signaling impacts osteoclasts’ ability to modulate immune cells. We aim to reduce TIBD and tumor burden by reducing the expansion of osteoclasts and shifting the immune cells to an anti-tumorigenic phenotype. Our studies will provide additional insight into the underlying mechanisms of the vicious cycle which will offer new treatment strategies for patients with osteolytic breast cancer. Citation Format: Dominique Parker, Verra Ngwa, Jin Chen, Julie Rhoades. Investigating the role of Epha2 in breast cancer-mediated myeloid cell expansion and function [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6866.

Abstract 5285: DKK1 blockade inhibits progression of bone metastases via multiple mechanisms and synergize with zoledronate treatment

Abstract Background: Despite the important breakthroughs of immune checkpoint blockade (ICB) therapy in multiple primary cancers, responses of ICB therapy in bone metastases remain extremely poor, largely due to the highly immunosuppressive bone metastasis microenvironment. However, the current understanding of bone metastasis microenvironment is still incomplete, and specific treatment targets for patients with bone metastasis are still lacking. Methods: Transcriptome sequencing data of gastric and breast cancer bone metastasis samples from The TCGA and GEO databases were obtained. The correlation between DKK1 expression and prognosis, intertumoral immune infiltration of bone-metastatic patients was analyzed. Mouse bone metastasis models from gastric, breast and lung cancer were established, and in vivo treatment efficacy of DKK1 and/or zoledronic acid was evaluated by micro-computed tomography (CT), micro-magnetic resonance imaging (MRI) and immunohistochemistry (IHC) staining. The changes of immune components wthin bone-tumor microenvironment were explored via flow cytometry, CyTOF and scRNA-seq analysis. The impact of DKK1 on different immune cell types was analyzed via in vitro co-culture models. Results: Serum detection of gastric cancer patients from our center showed that compared with non-metastatic patients, DKK1 concentration in patients with bone metastasis was the significantly increased (p&amp;lt;0.0001); and compared with other metastatic sites of breast cancer patients, bone metastases had the highest level of DKK1 mRNA expression (p&amp;lt;0.05). Using multiple bone metastasis mouse models, we found that DKK1 blockade significantly controlled the tumor burden of bone metastases. Results of micro-CT and TRAP staining showed that the bone destruction and osteoclast activity within bone lesions were significantly inhibited after DKK1 blockade. In addition, results of flow cytometry and immunofluorescence staining on bone metastasis samples showed that both innate and adaptive anti-immune responses were obviously improved after DKK1 blockade, including increased infiltration of CD8+ T cells, M1 macrophages and decreased infiltration of M2 macrophages. Mechanistically, DKK1 directly induced inhibition of CD8+ T cell activation, M2 polarization of macrophages and maturation of osteoclasts, which all contributes to the immune suppression in the bone metastasis microenvironment. Finally, combined therapy of DKK1 blockade and zoledronic acid had synergistic treatment effects in bone metastases. Conclusion: Our study provides novel insights into the multiple role of DKK1 in the bone metastasis immune microenvironment. DKK1 is a potential immunotherapeutic target for bone metastases, and dual blockade of DKK1 and zoledronic acid is a promising combination immunotherapy strategy for patients with bone metastasis. Citation Format: Tao Shi, Kaijie Liang, Yipeng Zhang, Xiaoyu Zhou, Baorui Liu, Jia Wei. DKK1 blockade inhibits progression of bone metastases via multiple mechanisms and synergize with zoledronate treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5285.

Bone metastases in patients with male breast carcinoma: About 3 cases

Bone metastases in patients with male breast carcinoma: About 3 cases

Deep learning algorithm-based multimodal MRI radiomics and pathomics data improve prediction of bone metastases in primary prostate cancer

PurposeBone metastasis is a significant contributor to morbidity and mortality in advanced prostate cancer, and early diagnosis is challenging due to its insidious onset. The use of machine learning to obtain prognostic information from pathological images has been highlighted. However, there is a limited understanding of the potential of early prediction of bone metastasis through the feature combination method from various sources. This study presents a method of integrating multimodal data to enhance the feasibility of early diagnosis of bone metastasis in prostate cancer.Methods and materialsOverall, 211 patients diagnosed with prostate cancer (PCa) at Gansu Provincial Hospital between January 2017 and February 2023 were included in this study. The patients were randomized (8:2) into a training group (n = 169) and a validation group (n = 42). The region of interest (ROI) were segmented from the three magnetic resonance imaging (MRI) sequences (T2WI, DWI, and ADC), and pathological features were extracted from tissue sections (hematoxylin and eosin [H&E] staining, 10 × 20). A deep learning (DL) model using ResNet 50 was employed to extract deep transfer learning (DTL) features. The least absolute shrinkage and selection operator (LASSO) regression method was utilized for feature selection, feature construction, and reducing feature dimensions. Different machine learning classifiers were used to build predictive models. The performance of the models was evaluated using receiver operating characteristic curves. The net clinical benefit was assessed using decision curve analysis (DCA). The goodness of fit was evaluated using calibration curves. A joint model nomogram was eventually developed by combining clinically independent risk factors.ResultsThe best prediction models based on DTL and pathomics features showed area under the curve (AUC) values of 0.89 (95% confidence interval [CI], 0.799–0.989) and 0.85 (95% CI, 0.714–0.989), respectively. The AUC for the best prediction model based on radiomics features and combining radiomics features, DTL features, and pathomics features were 0.86 (95% CI, 0.735–0.979) and 0.93 (95% CI, 0.854–1.000), respectively. Based on DCA and calibration curves, the model demonstrated good net clinical benefit and fit.ConclusionMultimodal radiomics and pathomics serve as valuable predictors of the risk of bone metastases in patients with primary PCa.

Disease characteristics and prognostic factors of colorectal cancer patients with bone metastasis: A real-world data from Turkey.

Bone metastasis is rarely seen in colorectal cancer (CRC) patients, and there is insufficient data available regarding such cases. The study aimed to identify the prognostic factors and characteristics associated with overall survival in patients with bone metastatic CRC. Data from bone metastatic CRC patients referred to a high-volume tertiary cancer center in Turkey, between January 2018 and April 2021, were retrospectively collected. The records of 150 consecutive patients treated for bone metastases due to CRC were reviewed. Overall survival curves were generated by the Kaplan-Meier method and analyzed using the log-rank test. Median age was 55 years (19-86 years). Bone metastases were more common in men and those with metachronous metastases. The axial skeleton was the most commonly involved site, and patients were frequently presented with single bone metastasis. Peritoneal metastases were significantly correlated with extra-axial metastases (P = 0.002), and radiotherapy was applied to axial metastases significantly, more frequently (P = 0.02). Lung metastasis was also more prevalent in K-RAS mutated patients (P = 0.008). The median survival time from diagnosis of bone metastasis was 8.3 months (95% confidence interval (CI), 5.5-10.6), and the three-year survival rate was 76.9% (95% CI, 69.8-84.0). Multivariate analysis revealed that brain metastases, right-sided colon tumor, high serum ALP, and Ca 19-9 levels were independent poor prognostic factors (P = 0.01, 0.02, <0.001, and 0.04, respectively). The location of CRC correlates significantly with the site of bone metastasis; the prognosis of CRC patients with bone metastasis is very poor, and the significant poor prognostic factors are brain metastases, right-sidedness, high serum ALP, and Ca 19-9 levels. More attention should be paid to bone metastasis in CRC patients.