A clinical-stage Nrf2 activator suppresses osteoclast differentiation via the iron-ornithine axis.

Activating Nrf2 by small molecules is a promising strategy to treat postmenopausal osteoporosis. However, there is currently no Nrf2 activator approved for treating chronic diseases, and the downstream mechanism underlying the regulation of Nrf2 on osteoclast differentiation remains unclear. Here, we found that bitopertin, a clinical-stage glycine uptake inhibitor, suppresses osteoclast differentiation and ameliorates ovariectomy-induced bone loss by activating Nrf2. Mechanistically, bitopertin interacts with the Keap1 Kelch domain and decreases Keap1-Nrf2 binding, leading to reduced Nrf2 ubiquitination and degradation. Bitopertin is associated with less adverse events than clinically approved Nrf2 activators in both mice and human subjects. Furthermore, Nrf2 transcriptionally activates ferroportin-coding gene Slc40a1 to reduce intracellular iron levels in osteoclasts. Loss of Nrf2 or iron supplementation upregulates ornithine-metabolizing enzyme Odc1, which decreases ornithine levels and thereby promotes osteoclast differentiation. Collectively, our findings identify a novel clinical-stage Nrf2 activator and propose a novel Nrf2-iron-ornithine metabolic axis in osteoclasts.

IL-17 promotes osteoclast-induced bone loss by regulating glutamine-dependent energy metabolism.

Osteoclasts consume an amount of adenosine triphosphate (ATP) to perform their bone resorption function in the development of osteoporosis. However, the mechanism underlying osteoclast energy metabolism has not been fully elucidated. In addition to glucose, glutamine (Glu) is another major energy carrier to produce ATP. However, the role of Glu metabolism in osteoclasts and the related molecular mechanisms has been poorly elucidated. Here we show that Glu is required for osteoclast differentiation and function, and that Glu deprivation or pharmacological inhibition of Glu transporter ASCT2 by V9302 suppresses osteoclast differentiation and their bone resorptive function. In vivo treatment with V9302 improved OVX-induced bone loss. Mechanistically, RNA-seq combined with in vitro and in vivo experiments suggested that Glu mediates the role of IL-17 in promoting osteoclast differentiation and in regulating energy metabolism. In vivo IL-17 treatment exacerbated OVX-induced bone loss, and this effect requires the participation of Glu or its downstream metabolite α-KG. Taken together, this study revealed a previously unappreciated regulation of IL-17 on energy metabolism, and this regulation is Glu-dependent. Targeting the IL-17-Glu-energy metabolism axis may be a potential therapeutic strategy for the treatment of osteoporosis and other IL-17 related diseases.

Cancer-Erythrocyte Membrane-Mimicking Fe3O4 Nanoparticles and DHJS for Ferroptosis/Immunotherapy Synergism in Tumors.

Ferroptosis is characterized by iron accumulation and lipid peroxidation. However, a clinical dose of Fe3O4 nanoparticles could not cause effective ferroptosis in tumors, and the mechanism is yet to be completely understood. In this study, using RNA-seq data, we found that tumor cells could feedback-activate the antioxidant system by upregulating Nrf-2 expression, thus avoiding ferroptosis caused by Fe3O4 nanoparticles. We also found that DHJS (a probe for ROS generation) can antagonize Nrf-2 expression when it synergizes with Fe3O4 nanoparticles, thus inducing ferroptosis in tumor cells. Considering these findings, we created a biomimetic hybrid cell membrane camouflaged by PLGA-loaded Fe3O4 and DHJS to treat osteosarcoma. The hybrid cell membrane endowed the core nanoparticle with the extension of blood circulation life and enhanced homologous targeting ability. In addition, DHJS and Fe3O4 in nanoparticles prompted synergistically lethal ferroptosis in cancer cells and induced macrophage M1 polarization as well as the infiltration of CD8(+) T cells and dendritic cells in tumors. In summary, this study provides novel mechanistic insights and practical strategies for ferroptosis induction of Fe3O4 nanoparticles. Meanwhile, the synthesized biomimetic nanoparticles exhibited synergistic ferroptosis/immunotherapy against osteosarcoma.

Inhibition of FAAH suppresses RANKL-induced osteoclastogenesis and attenuates ovariectomy-induced bone loss partially through repressing the IL17 pathway.

Fatty amide hydrolase (FAAH) is a key degradation enzyme of the endocannabinoid system, mainly responsible for the hydrolysis of arachidonic acid ethanolamine (AEA). Previous investigations have shown that FAAH is involved in a series of biological processes, such as inflammation, immune regulation, and transmembrane signal transduction of neurons. Endogenous cannabinoids and cannabinoid receptors have been reported to participate in the regulation of bone homeostasis by regulating the differentiation of osteoblasts and osteoclasts. We hypothesized that FAAH may play an important role in osteoclastogenesis based on the above evidence. The present study found that the FAAH expression was increased at both mRNA and protein levels during RANKL-induced osteoclastogenesis. Pharmacological and genetic inhibition of FAAH in bone marrow-derived macrophages (BMMs) inhibited osteoclastogenesis, F-actin ring formation, bone resorption, and osteoclast-specific gene expression in vitro. Moreover, intragastric administration of the FAAH inhibitor PF-04457845(PF) ameliorated ovariectomy (OVX)-induced bone loss in mice. Further investigation revealed that nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways were inhibited by PF treatment and FAAH knockdown. RNAseq indicated that the IL17 pathway was blocked by PF, and administration of recombinant murine IL17 protein could partially restore osteoclastogenesis and activate NF-κB and MAPK pathways. To sum up, our findings demonstrate that targeting FAAH could be a promising candidate strategy for treating osteoclast-related diseases, especially osteoporosis.

Impact of Limb Salvage on Prognosis of Patients Diagnosed With Extremity Bone and Soft Tissue Sarcomas.

Background: Although clinicians and patients with extremity bone and soft tissue (EBST) are increasingly interested in limb salvage surgery (LSS), because of the minimal damage to physical appearance and function, however, there is still a lack of large-scale population studies on whether LSS improves the prognosis of patients. Purpose: The aim of this study was to compare the survival of patients with EBST sarcomas after receiving LSS and amputation. Methods: To conduct the population-based study, we identified 6,717 patients with a histologically diagnosed bone sarcoma and 24,378 patients with a histologically diagnosed soft tissue sarcoma from the Surveillance, Epidemiology, and End Results database. We analyzed overall survival (OS), cancer-specific survival (CSS), and non-sarcoma survival (NSS) using the Kaplan-Meier method, log-rank test or Gray test, Cox regression model, propensity score-matched analysis, and landmark analysis. Results: LSS could improve the prognosis in patients with most EBST subtypes, except for Ewing sarcomas and MPNST. However, in the subgroup without distant metastases, limb salvage increased CSS only for patients with osteosarcoma, Ewing sarcoma, and leiomyosarcoma, as well as NSS for patients with chondrosarcoma and synovial sarcoma. Landmark analysis further demonstrated that sarcoma survivors surviving <10 years could benefit from LSS but not for long-term survivors ≥10 years. Moreover, for patients with distant metastases, LSS could improve survival of osteosarcoma patients but worsen CSS among patients with MPNST. Landmark analysis further demonstrated that LSS improved survival among osteosarcomas patients with distant metastases only within 1 year after surgery. Moreover, patients receiving LSS and those receiving amputation had a high risk of dying from different non-sarcoma diseases during the postoperative follow-up. Conclusions: The impact of limb salvage on the prognosis of patients depends on the pathological subtype and stage of EBST sarcomas.

Inhibition of MAT2A suppresses osteoclastogenesis and prevents ovariectomy-induced bone loss.

Methionine adenosyltransferase II alpha (MAT2A) is the key enzyme to transform methionine and adenosine-triphosphate (ATP) to S-adenosylmethionine (SAM), a general methyl-group donor in vitro. MAT2A has been reported to participate in the NF-κB pathway and maintain the methylated modification, which also affects osteoclastogenesis. In this study, we found the expression of MAT2A was increased upon RANKL stimulation. Pharmacological inhibition of MAT2A by its selective inhibitor AG-270 or genetic silencing by MAT2A-shRNA suppressed osteoclast formation and function in vitro. In vivo treatment with the inhibitor AG-270 also prevented OVX-induced bone loss. Further study revealed that the inhibition of MAT2A affected osteoclast differentiation mainly by suppressing crucial transcription factors and reactive oxygen species induced by RANKL. A quasi-targeted metabolomics assay performed by LC-MS/MS indicated that SAM was reduced by MAT2A knockdown, and the administration of SAM partly rescued the effects of MAT2A inhibition on osteoclastogenesis. These findings revealed that MAT2A is crucial for osteoclastogenesis and might be a potential target for the treatment of osteoporosis attributed to osteoclast dysfunction.

Inhibition of IRE1 suppresses the catabolic effect of IL-1ß on nucleus pulposus cell and prevents intervertebral disc degeneration in vivo.

Neck pain and low back pain are two of the major diseases, which causes patients a low quantify of life and a heavy economic burden, intervertebral disc degeneration (IDD) contributes to them, and the mechanism is not totally clear. The increased inflammatory cytokines including interleukin (IL)-1ß and tumor necrosis factor (TNF)α and downstream signaling pathways are involved. Inositol requiring enzyme 1 (IRE1) is a crucial enzyme that regulates endoplasmic reticulum (ER) stress. It is reported that IRE1 plays an important role in the activation of NF-κB, PI3K/Akt and MAPK signaling pathways. Considering this, we performed a series of experiments in vitro and in vivo to evaluate the role of IRE1 in the progress of IDD. We demonstrated that IRE1 pathway was induced by IL-1ß, inhibition of IRE1 suppressed the matrix degeneration of NP cells and ameliorated IDD grade in the punctured rat model. Further results indicated that inhibition of IRE1 suppressed H2O2 induced cell senescence, IL-1ß-induced cellular reactive oxygen species (ROS) level and the activation of NF-κB, PI3K/Akt and MAPK signaling pathways. It also played a crucial role in the apoptosis of NP cells and the progress of macrophage polarization. Our findings demonstrated that inhibition of IRE1 could suppress the degeneration of NP cells and prevent IDD in vivo. IRE1 may be a potential target for IDD treatment.

A Competing Risk-based Prognostic Model to Predict Cancer-specific Death of Patients with Spinal and Pelvic Chondrosarcoma.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: The aim of this study was to develop and validate a competing-risk-based prognostic model and a nomogram for predicting the three- and five-year probability of cancer-specific death (CSD) in patients with spinal and pelvic chondrosarcoma. SUMMARY OF BACKGROUND DATA: The issue of competing risk has rarely been addressed and discussed in survival analysis of bone sarcoma. In addition, the Fine and Gray model, a more accurate method for survival analysis in the context of competing risk, has also been less reported in prognostic study of chondrosarcoma. METHODS: A total of 623 patients with spinal or pelvic chondrosarcoma were identified from the SEER database and were divided into a training and a validation cohort. These two cohorts were used to develop and validate a prognostic model to predict the 3- and 5-year probability of CSD, considering non-CSD as competing risk. The C-index, calibration plot, and decision curve analysis were used to assess the predictive performance and clinical utility of the model. RESULTS: Older age (subdistribution hazards ratio [SHR]: 1.02, 95% confidence interval [CI]: 1.01∼1.03; P = 0.013), high grade (SHR: 2.68, 95% CI: 1.80∼3.99; P < 0.001), regional involvement (SHR: 1.66, 95% CI: 1.06∼2.58; P = 0.026), distant metastasis (SHR: 5.18, 95% CI: 3.11∼8.62; P < 0.001) and radical resection (SHR: 0.38, 95% CI: 0.24∼0.60; P < 0.001) were significantly associated with the incidence of CSD. These factors were used to build a competing-risk-based model and a nomogram to predict CSD. The C-index, calibration plot, and decision curve analysis indicated that the nomogram performs well in predicting CSD and is suitable for clinical use. CONCLUSION: A competing-risk based prognostic model is developed to predict the probability of CSD of patients with spinal and pelvic chondrosarcoma. This nomogram performs well and is suitable for clinical use.Level of Evidence: 4.

Suicide and accidental deaths among patients with primary malignant bone tumors.

BACKGROUND: It has been recognized that cancer is associated with a higher risk of suicide or accidental death. Earlier studies have evidenced that patients with malignant bone tumors usually experience psychological dysfunction and physical disability following surgery, which are shared risk factors between suicidal and accidental deaths. To our knowledge, there is no large population-based study on the risk of suicide or accidental death among patients with malignant bone tumors. QUESTIONS/PURPOSES: This study aimed to determine whether patients with primary malignant bone tumors are at a higher risk of suicide and accidental death than the general population and to identify the demographic and tumour-related characteristics and type of surgery associated with a higher risk of suicide and accidental death among these patients. METHODS: Overall, 50,817 patients diagnosed with primary malignant bone tumors between 1973 and 1975 were identified from the Surveillance, Epidemiology, and End Results database. The standardised mortality ratio (SMR) was calculated based on the general population's mortality data, gathered by the National Center for Health Statistics. The Cox regression model was developed to determine risk factors associated with a higher risk of suicide and accidental death. RESULTS: Patients with primary malignant bone tumors had a higher risk of suicide and accidental death than the general population in the United States (US) (SMR = 2.17; 95% confidence interval (CI) [1.80-2.62] and SMR = 1.73; 95% CI [1.54-1.95]). Compared with limb salvage, amputation significantly increased the risk of suicide (SMR = 3.99; 95% CI [2.52-6.34], hazard ratio (HR) = 2.32; 95% CI [1.31-4.09]; P < 0.01) but did not increase the risk of accidental death (SMR = 1.61; 95% CI [1.07-2.42], HR = 1.11; 95% CI [0.71-1.74]; P = 0.65). Higher suicide risk was observed among older patients whose age at diagnosis was more than 60 years (HR = 4.04; 95% CI [1.98-8.26]; P < 0.001), males (HR = 3.48; 95% CI [2.16-5.62]; P < 0.001), and whites (HR = 3.71; 95% CI [1.17-11.73]; P < 0.001). The risk of suicide and accidental death was highest in the first year after diagnosis (SMR = 2.95; 95% CI [1.86-4.69] and SMR = 2.02; 95% CI [1.48-2.74]). CONCLUSION: We first reported that patients with primary malignant bone tumors had a higher risk of suicide and accidental death than the general US population. Therefore, clinicians should pay more attention to the psychological status, physical function, and cognitive level of these survivors.

Individualized model for predicting COVID-19 deterioration in patients with cancer: A multicenter retrospective study.

The 2019 novel coronavirus has spread rapidly around the world. Cancer patients seem to be more susceptible to infection and disease deterioration, but the factors affecting the deterioration remain unclear. We aimed to develop an individualized model for prediction of coronavirus disease (COVID-19) deterioration in cancer patients. The clinical data of 276 cancer patients diagnosed with COVID-19 in 33 designated hospitals of Hubei, China from December 21, 2019 to March 18, 2020, were collected and randomly divided into a training and a validation cohort by a ratio of 2:1. Cox stepwise regression analysis was carried out to select prognostic factors. The prediction model was developed in the training cohort. The predictive accuracy of the model was quantified by C-index and time-dependent area under the receiver operating characteristic curve (t-AUC). Internal validation was assessed by the validation cohort. Risk stratification based on the model was carried out. Decision curve analysis (DCA) were used to evaluate the clinical usefulness of the model. We found age, cancer type, computed tomography baseline image features (ground glass opacity and consolidation), laboratory findings (lymphocyte count, serum levels of C-reactive protein, aspartate aminotransferase, direct bilirubin, urea, and d-dimer) were significantly associated with symptomatic deterioration. The C-index of the model was 0.755 in the training cohort and 0.779 in the validation cohort. The t-AUC values were above 0.7 within 8 weeks both in the training and validation cohorts. Patients were divided into two risk groups based on the nomogram: low-risk (total points ≤ 9.98) and high-risk (total points > 9.98) group. The Kaplan-Meier deterioration-free survival of COVID-19 curves presented significant discrimination between the two risk groups in both training and validation cohorts. The model indicated good clinical applicability by DCA curves. This study presents an individualized nomogram model to individually predict the possibility of symptomatic deterioration of COVID-19 in patients with cancer.

Characteristics, incidence, and risk factors for death from fatal pneumonia among patients with primary malignant bone tumors: a SEER-based observational study.

BACKGROUND: (I) To determine whether patients with malignant bone tumors had a higher risk of dying from pneumonia compared with the general US population; (II) to identify the independent risk factor associated with fatal pneumonia among these patients. METHODS: We identified 18,583 patients diagnosed with primary malignant bone tumors between 1973 and 2016 from the Surveillance, Epidemiology, and End Results (SEER) database. Standardized mortality ratios (SMRs) were calculated based on the mortality data of the general population gathered by the National Center for Health Statistics, which provided the risk of death from pneumonia among cancer patients relative to that of the general population. Given that other causes of death were considered as competing events, we also designed the Fine-Gray model to identify demographic and tumor-related characteristics associated with a higher risk of dying from pneumonia among these patients. RESULTS: Patients with primary malignant bone tumors had a higher risk of dying from pneumonia than the general population after adjusting the distribution difference of age, sex, and race among them (SMR =2.79; 95% CI: 2.17-3.59). The older age, Black and earlier period of diagnosis were found to be the independent prognostic factor for a higher risk of death from pneumonia for these patients. Additionally, amputation due to malignant bone tumors significantly increased the risk of death from pneumonia compared with non-surgery. The highest mortality rate of pneumonia was observed among patients with chordoma. Interaction tests demonstrated that amputation only increased the relative risk of fatal pneumonia among patients with osteosarcoma. Throughout the follow-up period, the mortality rate of fatal pneumonia was the highest within the first year after diagnosis, and the highest relative suicide risks persisted over time in patients with osteosarcoma. CONCLUSIONS: To mitigate the risk of fatal pneumonia among patients with bone tumors, we call for long-term clinical monitoring of the lung condition among these patients, especially for those after amputation for bone tumors.

Association between recent oncologic treatment and mortality among patients with carcinoma who are hospitalized with COVID-19: A multicenter study.

BACKGROUND: To the authors' knowledge, little is known regarding the association between recent oncologic treatment and mortality in patients with cancer who are infected with coronavirus disease 2019 (COVID-19). The objective of the current study was to determine whether recent oncologic treatment is associated with a higher risk of death among patients with carcinoma who are hospitalized with COVID-19. METHODS: Data regarding 248 consecutive patients with carcinoma who were hospitalized with COVID-19 were collected retrospectively from 33 hospitals in Hubei Province, China, from January 1, 2020, to March 25, 2020. The follow-up cutoff date was July 22, 2020. Univariable and multivariable logistic regression analyses were performed to identify variables associated with a higher risk of death. RESULTS: Of the 248 patients enrolled, the median age was 63 years and 128 patients (52%) were male. On admission, 147 patients (59%) did not undergo recent oncologic treatment, whereas 32 patients (13%), 25 patients (10%), 12 patients (5%), and 10 patients (4%), respectively, underwent chemotherapy, surgery, targeted therapy, and radiotherapy. At the time of last follow-up, 51 patients (21%) were critically ill during hospitalization, 40 of whom had died. Compared with patients without receipt of recent oncologic treatment, the mortality rate of patients who recently received oncologic treatment was significantly higher (24.8% vs 10.2%; hazard ratio, 2.010 [95% CI, 1.079-3.747; P = .027]). After controlling for confounders, recent receipt of chemotherapy (odds ratio [OR], 7.495; 95% CI, 1.398-34.187 [P = .015]), surgery (OR, 8.239; 95% CI, 1.637-41.955 [P = .012]), and radiotherapy (OR, 15.213; 95% CI, 2.091-110.691 [P = .007]) were identified as independently associated with a higher risk of death. CONCLUSIONS: The results of the current study demonstrated a possible association between recent receipt of oncologic treatment and a higher risk of death among patients with carcinoma who are hospitalized with COVID-19.

Primary Tumor Resection Prolongs Survival in Spinal Chondrosarcoma Patients With Distant Metastasis.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To investigate (1) whether resection of primary tumor improves survival of metastatic spinal chondrosarcoma patients and (2) which subgroups of metastatic spinal chondrosarcoma patients benefit more from primary tumor resection. SUMMARY OF BACKGROUND DATA: Surgical resection is the mainstay of treatment for spinal chondrosarcoma, as chondrosarcoma is inherently resistant to radiotherapy and chemotherapy. However, evidence which justifies resection of the primary tumor for patients with metastatic spinal chondrosarcoma is still lacking. METHODS: We retrospectively included 110 patients with metastatic spinal chondrosarcoma in the Surveillance, Epidemiology, and End Results database from 1983 to 2016. The association between primary tumor resection and survival was evaluated using Kaplan-Meier analyses, log-rank tests, and multivariable Cox analyses. The effect of primary tumor resection on survival was further assessed in subgroups stratified by histologic subtype, tumor grade, and age. RESULTS: Overall, 110 patients were divided into surgery group (n = 55, 50%) and nonsurgery group (n = 55, 50%). Primary tumor resection was associated with both prolonged overall survival (hazard ratio 0.262, 95% confidence interval 0.149-0.462, P < 0.001) and cancer-specific survival (hazard ratio 0.228, 95% confidence interval 0.127-0.409, P < 0.001). When we focused on surgical effects in subgroups, primary tumor resection conferred survival advantage on patients with conventional subtype, grade I to III malignancy, and an age younger than 70 years old (P < 0.001 for overall and cancer-specific survival). However, primary tumor resection brought limited survival benefit for patients with dedifferentiated subtype and patients over 70 years old. CONCLUSION: The present population-based study for the first time reports a clear association between primary tumor resection and prolonged survival in metastatic spinal chondrosarcoma patients. Specifically, primary tumor resection was associated with improved survival in patients with conventional subtype, grade I to III malignancy, and an age younger than 70 years old. LEVEL OF EVIDENCE: 4.

A nomogram for predicting mortality in patients with COVID-19 and solid tumors: a multicenter retrospective cohort study.

BACKGROUND: Individualized prediction of mortality risk can inform the treatment strategy for patients with COVID-19 and solid tumors and potentially improve patient outcomes. We aimed to develop a nomogram for predicting in-hospital mortality of patients with COVID-19 with solid tumors. METHODS: We enrolled patients with COVID-19 with solid tumors admitted to 32 hospitals in China between December 17, 2020, and March 18, 2020. A multivariate logistic regression model was constructed via stepwise regression analysis, and a nomogram was subsequently developed based on the fitted multivariate logistic regression model. Discrimination and calibration of the nomogram were evaluated by estimating the area under the receiver operator characteristic curve (AUC) for the model and by bootstrap resampling, a Hosmer-Lemeshow test, and visual inspection of the calibration curve. RESULTS: There were 216 patients with COVID-19 with solid tumors included in the present study, of whom 37 (17%) died and the other 179 all recovered from COVID-19 and were discharged. The median age of the enrolled patients was 63.0 years and 113 (52.3%) were men. Multivariate logistic regression revealed that increasing age (OR=1.08, 95% CI 1.00 to 1.16), receipt of antitumor treatment within 3 months before COVID-19 (OR=28.65, 95% CI 3.54 to 231.97), peripheral white blood cell (WBC) count ≥6.93 ×109/L (OR=14.52, 95% CI 2.45 to 86.14), derived neutrophil-to-lymphocyte ratio (dNLR; neutrophil count/(WBC count minus neutrophil count)) ≥4.19 (OR=18.99, 95% CI 3.58 to 100.65), and dyspnea on admission (OR=20.38, 95% CI 3.55 to 117.02) were associated with elevated mortality risk. The performance of the established nomogram was satisfactory, with an AUC of 0.953 (95% CI 0.908 to 0.997) for the model, non-significant findings on the Hosmer-Lemeshow test, and rough agreement between predicted and observed probabilities as suggested in calibration curves. The sensitivity and specificity of the model were 86.4% and 92.5%. CONCLUSION: Increasing age, receipt of antitumor treatment within 3 months before COVID-19 diagnosis, elevated WBC count and dNLR, and having dyspnea on admission were independent risk factors for mortality among patients with COVID-19 and solid tumors. The nomogram based on these factors accurately predicted mortality risk for individual patients.

Predict overall survival of spinal conventional chordoma: Development and assessment of a new predictive nomogram.

OBJECTIVE: To predict the 5-year overall survival (OS) rate in patients with conventional chordoma of the spine PATIENTS AND METHODS: The Surveillance, Epidemiology, and End Results (SEER) Registry was used to identify patients with conventional chordoma of the spine from 1994 to 2013. The entire cohort(n = 294) was randomly divided into training (n = 147) and validation (n = 147) cohorts to construct a nomogram. We used the univariate Log-rank test and multivariate Cox model to examine the independent prognostic factors associated with OS. These prognostic factors were integrated to construct a nomogram through R studio. The predictive and validating capacity of the nomogram was calculated by Harrell's concordance index (C-index) and calibration curves. RESULTS: A total of 294 patients were identified with conventional chordoma of the spine. The patients' age at diagnosis, tumor size, EOD (extent of disease), and treatment were independent prognostic factors and associated with OS. These prognostic factors were incorporated to construct a nomogram. The concordance index for the nomogram was 0.771 and 0.732 in the training cohort and validation cohort, respectively. Internal and external calibration curves for 5-year OS showed excellent matching between nomogram prediction and observed outcomes. CONCLUSIONS: The findings of this study provide population-based estimates of patients with conventional chordoma of the spine. Using this nomogram, surgeons can classify patients into different risk groups and achieve individualized treatment.

Low-Dose Sorafenib Acts as a Mitochondrial Uncoupler and Ameliorates Nonalcoholic Steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is becoming one of the leading causes of hepatocellular carcinoma (HCC). Sorafenib is the only first-line therapy for advanced HCC despite its serious adverse effects. Here, we report that at an equivalent of approximately one-tenth the clinical dose for HCC, sorafenib treatment effectively prevents the progression of NASH in both mice and monkeys without any observed significant adverse events. Mechanistically, sorafenib's benefit in NASH is independent of its canonical kinase targets in HCC, but involves the induction of mild mitochondrial uncoupling and subsequent activation of AMP-activated protein kinase (AMPK). Collectively, our findings demonstrate a previously unappreciated therapeutic effect and signaling mechanism of low-dose sorafenib treatment in NASH. We envision that this new therapeutic strategy for NASH has the potential to translate into a beneficial anti-NASH therapy with fewer adverse events than is observed in the drug's current use in HCC.

Conditional Survival Analysis for Spinal Chondrosarcoma Patients After Surgical Resection.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To evaluate conditional survival after surgical resection for spinal chondrosarcoma patients. SUMMARY OF BACKGROUND DATA: Survival estimates are usually reported as survival from the time of surgery, but survival probabilities can change over time. Conditional survival, which is a measure of prognosis for patients who have survived a defined period of time, may be more clinically precise and relevant. However, data on conditional survival for spinal chondrosarcoma patients after surgical resection are still lacking. METHODS: We used the Surveillance, Epidemiology, and End Results (SEER) database to identify 436 spinal chondrosarcoma patients who underwent surgical resection from 1994 and 2013. Kaplan-Meier analyses and Cox regression modeling were performed to evaluate prognostic factors associated with overall survival. Five-year conditional survival (i.e., probability of surviving an additional 5 years, given that a patient has already survived x years) was calculated as 5-CS(x) = OS(x+5)/OS(x). The effect of prognostic factors on conditional survival was also explored. RESULTS: Four hundred thirty six patients were included in the study cohort. Overall, 1-, 3-, and 5-year overall survival were 92.8%, 79.1%, and 70.3%, respectively. Five-year conditional survival at 1, 3, and 5 years after surgery were 72.9%, 79.0%, and 87.5%. The overall survival rates were lower in cases of age more than or equal to 60 years, male patient, dedifferentiated subtype, Grade III tumor, tumor size more than or equal to 10 cm, distant metastasis, and radiotherapy. Conditional survival improved over time in each subgroup divided by age, sex, race, year of diagnosis, grade, tumor size, extent of disease (EOD), and radiotherapy. In addition, patients with the least favorable prognosis at baseline experienced the greatest increase in 5-year conditional survival over time (e.g., Grade I/II: 78.0%-89.7%, Δ11.7% vs. Grade III: 36.5%-66.6%, Δ30.1%; Localized/Regional: 72.9%-88.1%, Δ15.2% vs. Distant: 43.5%-74.1%, Δ30.6%). CONCLUSION: Conditional survival for spinal chondrosarcoma patients after surgical resection improves over time, especially for patients with initial high-risk characteristics. Information derived from conditional survival analysis may provide individualized approaches to surveillance and treatment of spinal chondrosarcoma. LEVEL OF EVIDENCE: 4.

Survival analysis of patients with metastatic osteosarcoma: a Surveillance, Epidemiology, and End Results population-based study.

PURPOSE: The present study is aimed at investigating whether (1) primary tumour surgery confers an improved survival on patients with metastatic osteosarcoma and (2) primary tumour surgery influences survival of patients with metastatic osteosarcoma differently according to primary tumour site. METHODS: We retrospectively identified 517 patients with high-grade, metastatic osteosarcoma in the Surveillance, Epidemiology, and End Results (SEER) database between 1994 and 2013. The effect of primary tumour surgery on survival was assessed using Kaplan-Meier analyses, log-rank tests, and multivariate Cox proportional hazard regression modeling. RESULTS: Of those 517 patients with metastatic osteosarcoma in the cohort, 351 patients (68%) underwent primary surgery, and 166 patients (32%) did not undergo surgery. Primary tumour surgery was associated with increased overall survival (hazard ratio (HR) = 0.457, 95% CI 0.354-0.590, p < 0.001) and cancer-specific survival (HR = 0.422, 95% CI 0.325-0.550, p < 0.001). When we focused on different primary tumour sites, receipt of primary tumour surgery significantly prolonged the survival of patients with extremity osteosarcoma (p < 0.05 for overall and cancer-specific survival). However, for patients with pelvis/spine osteosarcoma, both univariate and multivariate analyses indicated that primary tumour surgery might not be associated with improved survival (p > 0.05 for overall and cancer-specific survival). CONCLUSIONS: Our study is the first population-based analysis to provide evidence of a favourable prognostic impact of primary tumour surgery on metastatic extremity osteosarcoma patients but not metastatic axial (pelvis/spine) osteosarcoma patients. Moreover, we found that surgery type (resection of the primary tumor without amputation vs. amputation) did not influence survival in patients with metastatic osteosarcoma.

Does Resection of the Primary Tumor Improve Survival in Patients With Metastatic Chondrosarcoma?

BACKGROUND: Although surgical resection or amputation has been the mainstay of localized chondrosarcoma management for many decades, its efficacy in patients with metastatic chondrosarcoma remains unknown, and likewise we do not know whether there are any tumor- or patient-related factors associated with better survival after surgery for metastatic chondrosarcoma. QUESTIONS/PURPOSES: (1) Is resection of the primary tumor associated with improved survival in patients with metastatic chondrosarcoma? (2) Which subgroups of patients with chondrosarcoma benefit more from resection in terms of survival? METHODS: We identified 200 of 222 patients with metastatic chondrosarcoma in the Surveillance, Epidemiology, and End Results (SEER) database between 1988 and 2014 based on the exclusion criteria. Among those patients, 107 (53.5%) underwent primary tumor resection or amputation. Patient information, including demographics (patient age, gender, race, year of diagnosis), tumor characteristics (primary site, histologic subtype, tumor grade, tumor size), and treatment (record of operation and radiation), was collected and included in the study. Kaplan-Meier analyses, log-rank tests, competing risks framework, multivariable Cox regression modeling, and interaction tests were conducted to assess the association of primary tumor resection and survival in the overall cohort and subgroups. RESULTS: Resection of the primary tumor was associated with improved overall survival (hazard ratio [HR], 0.481; 95% confidence interval [CI], 0.340-0.680; p < 0.001) and cancer-specific survival (HR, 0.493; 95% CI, 0.343-0.709; p < 0.001) after controlling for confounding variables. After controlling further for age, histologic subtype, and grade, primary tumor resection was associated with a survival advantage in patients with conventional subtype and Grade II chondrosarcoma (conventional subtype: HR, 0.403; 95% CI, 0.260-0.623 for overall survival and HR, 0.396; 95% CI, 0.250-0.627 for cancer-specific survival). However, primary tumor resection was not associated with increased survival in patients with metastatic chondrosarcoma who had the dedifferentiated subtype and Grade III malignancy. CONCLUSIONS: The present study demonstrates a possible favorable association between primary tumor resection and survival in some patients with metastatic chondrosarcoma at initial diagnosis. Specifically, patients with conventional subtypes and Grade II malignancies who underwent primary tumor resection had better survival compared with those patients who did not have primary tumor resection. Thus, there might be a benefit from primary tumor resection in these patients, but given the limitations of this database, further prospective studies or randomized trials are needed to confirm our findings. In the meantime, this information might be helpful to consider when discussing surgical options with patients who have conventional, Grade 2 metastatic chondrosarcoma at diagnosis. LEVEL OF EVIDENCE: Level III, therapeutic study.