Preclinical development and evaluation of nanobody-based CD70-specific CAR T cells for the treatment of acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) treatment remains challenging. CD70 was reported as a promising AML-specific antigen. Preclinically, CAR T-cell with single-chain-variable fragment (scFv) or truncated CD27 targeting CD70 has been reported to treat AML. However, various disadvantages including spontaneous exhaustion, proteinase-mediated loss of functional receptors, and high immunogenicity, limited its further application to clinical settings. Alternatively, the single-variable domain on heavy chain (VHH), also known as nanobodies, with comparable binding ability and specificity, provides an optional solution. METHOD: We generated CD70 knocked-out novel nanobody-based anti-CD70-CAR T-cells (nb70CAR-T) with two different VHHs for antigen detection. Next, we detected the CD70 expression on primary AML blasts by flow cytometry and associated the efficacy of nb70CAR-T with the target antigen density. Finally, epigenetic modulators were investigated to regulate the CD70 expression on AML cells to promote the functionality of nb70CAR-T. RESULTS: Our nb70CAR-T exhibited expected tumoricidal functionality against CD70-expressed cell lines and primary AML blasts. However, CD70 expression in primary AML blasts was not consistently high and nb70CAR-T potently respond to an estimated 40.4% of AML patients when the CD70 expression level was over a threshold of 1.6 (MFI ratio). Epigenetic modulators, Decitabine and Chidamide can up-regulate CD70 expression on AML cells, enhancing the treatment efficacy of nb70CAR-T. CONCLUSION: CD70 expression in AML blasts was not fully supportive of its role in AML targeted therapy as reported. The combinational use of Chidamide and Decitabine with nb70CAR-T could provide a new potential for the treatment of AML.

A phase 1 study of a novel fully human BCMA-targeting CAR (CT103A) in patients with relapsed/refractory multiple myeloma.

B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapies have shown efficacy in relapsed/refractory multiple myeloma (RRMM). Because the non-human originated antigen-targeting domain may limit clinical efficacy, we developed a fully human BCMA-specific CAR, CT103A, and report its safety and efficacy in a phase 1 trial. Eighteen consecutive patients with RRMM, including 4 with prior murine BCMA CAR exposures, were enrolled. CT103A was administered at 1, 3, and 6 × 106 CAR-positive T cells/kg in the dose-escalation phase, and 1 × 106 CAR-positive T cells/kg in the expansion cohort. The overall response rate was 100%, with 72.2% of the patients achieving complete response or stringent complete response. For the 4 murine BCMA CAR-exposed patients, 3 achieved stringent complete response, and 1 achieved a very good partial response. At 1 year, the progression-free survival rate was 58.3% for all cohorts and 79.1% for the patients without extramedullary myeloma. Hematologic toxicities were the most common adverse events; 70.6% of the patients experienced grade 1 or 2 cytokine release syndromes. No immune effector cell-associated neurotoxicity syndrome was observed. To the cutoff date, CAR transgenes were detectable in 77.8% of the patients. The median CAR transgene persistence was 307.5 days. Only 1 patient was positive for the anti-drug antibody. Altogether, CT103A is safe and highly active in patients with RRMM and can be developed as a promising therapy for RRMM. Patients who relapsed from prior murine BCMA CAR T-cell therapy may still benefit from CT103A. This trial was registered at http://www.chictr.org.cn as #ChiCTR1800018137.

Development and functional characterization of novel fully human anti-CD19 chimeric antigen receptors for T-cell therapy.

Impressive outcomes have been achieved by chimeric antigen receptor (CAR)-T cell therapy using murine-derived single-chain variable fragment (scFv) FMC63 specific for CD19 in patients with B cell malignancies. However, evidence suggests that human anti-mouse immune responses might be responsible for poor persistence and dysfunction of CAR-T cells, leading to poor outcomes or early tumor recurrence. Substituting a fully human scFv for murine-derived scFv may address this clinically relevant concern. In this study, we discovered two human anti-CD19 scFv candidates through an optimized protein/cell alternative panning strategy and evaluated their function in CAR-T cells and CD19/CD3 bispecific antibody formats. The two clones exhibited excellent cytotoxicity in CAR-T cells and bispecific antibodies in vitro compared with the benchmarks FMC63 CAR-T cells and blinatumomab. Furthermore, Clone 78-BBz CAR-T cells exhibited similar in vivo antitumor activity to FMC63-BBz CAR-T cells. Our results indicate that Clone 78-BBz CAR has excellent efficacy and safety profile and is a good candidate for clinical development.

A novel LRRFIP1-ALK fusion in inflammatory myofibroblastic tumor of hip and response to crizotinib.

An inflammatory myofibroblastic tumor (IMT) is a rare invasive soft tissue mass with intramuscular penetration that is primarily treated via a surgical procedure. However, with unclear boundaries and a high rate of relapse, there is no standard treatment for recurrence or unresectable tumors. It is noteworthy that approximately half of IMTs harbor genetic rearrangements of the anaplastic lymphoma kinase (ALK). ALK inhibitors have been used successfully in the treatment of IMTs with a variety of ALK fusions. Here, we present a case of a 15-year-old patient with IMT around the hip. Next-generation sequencing (NGS) revealed an LRRFIP1-ALK fusion, which has not yet been reported in the literature. Crizotinib, an ALK inhibitor, was effective in the treatment of this patient, indicating that ALK inhibitors may be effective for IMT with LRRFIP1-ALK fusions. This report expands the list of gene fusions in IMTs and highlights a new target for treatment.

Recurrence and survival factors analysis of 171 cases of sacral chordoma in a single institute.

PURPOSE: To evaluate postoperative recurrence, survival and metastasis results and related factors of sacral chordoma. METHODS: Between 1978 and 2013, a total of 171 patients with sacral chordoma were diagnosed at our institution and 162 cases underwent operation. The clinical characteristics, treatment and outcomes of all these patients were reviewed. RESULTS: The 3-year recurrence free survival rate was 83.1%. The median recurrence free survival time was 73 ± 7.8 months. Tumor level in sacrum and surgical margin were significant factors influencing recurrence. Recurrence was significant factor influencing metastasis. One hundred and fifty-seven cases were followed up for an average of 55.6 months. 135 cases (86%) survived, 37 cases (23.6%) developed recurrence, and 17 cases (10.8%) developed metastasis. The overall 5- and 10-year survival rate was 88.3% and 59.6%, respectively. Age (p = 0.037) and metastasis (p = 0.001) were significant factors influencing survival. The 3-year recurrence free survival rate was 80.1%. The median recurrence free survival time was 69 ± 12.7 months. Tumor level in sacrum (p = 0.035) and surgical margin (p = 0.009) were significant factors influencing recurrence. Seventeen cases (10.8%) had metastasis. Recurrence (p = 0.016) was significant factors influencing metastasis. CONCLUSIONS: Sacral chordoma tended to occur in elderly male patients and locate below sacral 3 level. The recurrence rate was high, especially for tumor above sacral 3 level. Wide surgical margin is very important for good local control. The patients with metastasis had poor prognosis.

The effects of temperature, salinity, concentration and PEGylated lipid on the spontaneous nanostructures of bicellar mixtures.

The self-assembling morphologies of low-concentration (mostly 1 and 10mg/mL) bicellar mixtures composed of zwitterionic dipalmitoyl (di-C16) phosphatidylcholine (DPPC), dihexanoyl (di-C6) phosphatidylcholine (DHPC), and negatively charged dipalmitoyl (di-C16) phosphatidylglycerol (DPPG) were investigated using small angle neutron scattering, dynamic light scattering and transmission electron microscopy. A polyethylene glycol conjugated (PEGylated) lipid, distearoyl phosphoethanolamine-[methoxy (polyethyleneglycol)-2000] (PEG2000-DSPE), was incorporated in the system at 5mol% of the total lipid composition. The effects of several parameters on the spontaneous structures were studied, including temperature, lipid concentration, salinity, and PEG2000-DSPE. In general, nanodiscs (bicelles) were observed at low temperatures (below the melting temperature, TM of DPPC) depending on the salinity of the solutions. Nanodisc-to-vesicle transition was found upon the elevation of temperature (above TM) in the cases of low lipid concentration in the absence of PEG2000-DSPE or high salinity. Both addition of PEG2000-DSPE and high lipid concentration stabilize the nanodiscs, preventing the formation of multilamellar vesicles, while high salinity promotes vesiculation and the formation of aggregation. This study suggests that the stability of such nanodiscs is presumably controlled by the electrostatic interactions, the steric effect induced by PEG2000-DSPE, and the amount of DHPC located at the disc rim.

Precise single column resection and reconstruction with femoral head plus total hip replacement for primary malignant peri-acetabulum tumors.

To evaluate whether single acetabular column can be reserved and the effect of reconstruction with femoral head plus total hip replacement (THR) for primary malignant peri-acetabulum tumors. From 2007 to 2015, nineteen patients with primary malignant peri-acetabulum tumors were enrolled. All cases underwent single column resection with clear surgical margins. Ten of the 19 tumor's resections were assisted by computer navigation. Femoral heads were applied to reconstruct anterior or posterior column defects; THR was used for joint reconstruction. The surgical safety, oncologic outcome and prosthesis survivorship and function were evaluated by regular follow-up. The average follow-up period was 65.9 months. Surgical margins contained wide resection in 12 cases and marginal resection in 7 cases. One patient with Ewing's sarcoma died 14 months postoperative due to lung metastasis. One case with chondrosarcoma had recurrence. One prosthesis was removed due to infection. The average MusculoSkeletal Tumor Society (MSTS) function score was 83.7%. Due to the relative small number of cases, there was no significant difference in the recurrence rate and prosthesis failure rate between the navigation group and non-navigation group. Single column resection and reconstruction with femoral head autograft plus THR is an effective, safe method with less complication rate and better functional outcome for patients with peri-acetabular tumors.

The correlation between clinical outcomes and genomic analysis with high risk factors for the progression of osteosarcoma.

Osteosarcoma (OS) is a rare but aggressive malignancy. Despite previous reports, molecular characterization of this disease is not well understood, and little is known regarding OS in Chinese patients. Herein, we analyzed the genomic signatures of 73 Chinese OS cases. TP53, NCOR1, LRP1B, ATRX, RB1, and TFE3 were the most frequently mutated gene in our OS cohort. In addition, the genomic analysis of Western OS patients was performed. Notably, there were remarkable disparities in mutational landscape, base substitution pattern, and tumor mutational burden between the Chinese and Western OS cohorts. Specific molecular mechanisms, including DNA damage repair (DDR) gene mutations, copy number variation (CNV) presence, aneuploidy, and intratumoral heterogeneity, were associated with disease progression. Additionally, 30.1% of OS patients carried clinically actionable alterations, which were mainly enriched in PI3K, MAPK, DDR, and RTK signaling pathways. A specific molecular subtype incorporating DDR alterations and CNVs was significantly correlated with distant metastasis-free survival and event-free survival, and this correlation was observed in all subgroups with different characteristics. These findings comprehensively elucidated the genomic profile and revealed novel prognostic factors in OS, which would contribute to understanding this disease and promoting precision medicine of this population.

Morphological characterization of DMPC/CHAPSO bicellar mixtures: a combined SANS and NMR study.

Spontaneously forming structures of a system composed of dimyristoyl phosphatidylcholine (DMPC) and 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propanesulfonate (CHAPSO) were studied by small-angle neutron scattering (SANS), (31)P NMR, and stimulated echo (STE) pulsed field gradient (PFG) (1)H NMR diffusion measurements. Charged lipid dimyristoyl phosphatidylglycerol (DMPG) was used to induce different surface charge densities. The structures adopted were investigated as a function of temperature and lipid concentration for samples with a constant molar ratio of long-chain to short-chain lipids (= 3). In the absence of DMPG, zwitterionic bicellar mixtures exhibited a phase transition from discoidal bicelles, or ribbons, to multilamellar vesicles either upon dilution or with increased temperature. CHAPSO-containing mixtures showed a higher thermal stability in morphology than DHPC-containing mixtures at the corresponding lipid concentrations. In the presence of DMPG, discoidal bicelles (or ribbons) were also found at low temperature and lower lipid concentration mixtures. At high temperature, perforated lamellae were observed in high-concentration mixtures (≥7.5 wt %) whereas uniform unilamellar vesicles and bicelles formed in low-concentration mixtures (≤2.5 wt %), respectively, when the mixtures were moderately and highly charged. From the results, spontaneous structural diagrams of the zwitterionic and charged systems were constructed.

Mechanisms of protective immune responses induced by the Plasmodium falciparum circumsporozoite protein-based, self-assembling protein nanoparticle vaccine.

BACKGROUND: A lack of defined correlates of immunity for malaria, combined with the inability to induce long-lived sterile immune responses in a human host, demonstrate a need for improved understanding of potentially protective immune mechanisms for enhanced vaccine efficacy. Protective sterile immunity (>90%) against the Plasmodium falciparum circumsporozoite protein (CSP) has been achieved using a transgenically modified Plasmodium berghei sporozoite (Tg-Pb/PfCSP) and a self-assembling protein nanoparticle (SAPN) vaccine presenting CSP epitopes (PfCSP-SAPN). Here, several possible mechanisms involved in the independently protective humoral and cellular responses induced following SAPN immunization are described. METHODS: Inbred mice were vaccinated with PfCSP-SAPN in PBS. Serum antibodies were harvested and effects on P. falciparum sporozoites mobility and integrity were examined using phase contrast microscopy. The functionality of SAPN-induced antibodies on inhibition of sporozoite invasion and growth within primary human hepatocytes was also examined. The internal processing of SAPN by bone marrow-derived dendritic cells (BMDDC), using organelle-specific, fluorescent-tagged antibody or gold-encapsulated SAPN, was observed using confocal or electron microscopy, respectively. RESULTS: The results of this work demonstrate that PfCSP-SAPN induces epitope-specific antibody titers, predominantly of the Th2 isotype IgG1, and that serum antibodies from PfCSP-SAPN-immunized mice appear to target P. falciparum sporozoites via the classical pathway of complement. This results in sporozoite death as indicated by cessation of motility and the circumsporozoite precipitation reaction. Moreover, PfCSP-SAPN-induced antibodies are able to inhibit wild-type P. falciparum sporozoite invasion and growth within cultured primary human hepatocytes. In addition, the observation that PfCSP-SAPN are processed (and presented) to the immune system by dendritic cells in a slow and continuous fashion via transporter associated with antigen processing (TAP) recruitment to the early endosome (EE), and have partially delayed processing through the endoplasmic reticulum, has the potential to induce the long-lived, effector memory CD8+ T-cells as described previously. CONCLUSION: This paper describes the examination of humoral and cellular immune mechanisms induced by PfCSP-SAPN vaccination which result in sterile host protection against a transgenic P. berghei malaria sporozoite expressing the P. falciparum CSP, and which significantly inhibits native P. falciparum sporozoites from invading and developing within cultured human hepatocytes. These results may indicate the type and mode of action of protective antibodies needed to control P. falciparum sporozoites from infecting humans as well as a potential mechanism of induction of protective long-lived effector memory CD8+ T-cells.

The biodistribution of self-assembling protein nanoparticles shows they are promising vaccine platforms.

BACKGROUND: Because of the need to limit side-effects, nanoparticles are increasingly being studied as drug-carrying and targeting tools. We have previously reported on a scheme to produce protein-based self-assembling nanoparticles that can act as antigen display platforms. Here we attempted to use the same system for cancer-targeting, making use of a C-terminal bombesin peptide that has high affinity for a receptor known to be overexpressed in certain tumors, as well as an N-terminal polyhistidine tag that can be used for radiolabeling with technetium tricarbonyl. RESULTS: In order to increase circulation time, we experimented with PEGylated and unPEGylated varities typo particle. We also tested the effect of incorporating different numbers of bombesins per nanoparticle. Biophysical characterization determined that all configurations assemble into regular particles with relatively monodisperse size distributions, having peaks of about 33-36 nm. The carbonyl method used for labeling produced approximately 80% labeled nanoparticles. In vitro, the nanoparticles showed high binding, both specific and non-specific, to PC-3 prostate cancer cells. In vivo, high uptake was observed for all nanoparticle types in the spleens of CD-1 nu/nu mice, decreasing significantly over the course of 24 hours. High uptake was also observed in the liver, while only low uptake was seen in both the pancreas and a tumor xenograft. CONCLUSIONS: The data suggest that the nanoparticles are non-specifically taken up by the reticuloendothelial system. Low uptake in the pancreas and tumor indicate that there is little or no specific targeting. PEGylation or increasing the amount of bombesins per nanoparticle did not significantly improve targeting. In particular, the uptake in the spleen, which is a primary organ of the immune system, highlights the potential of the nanoparticles as vaccine carriers. Also, the decrease in liver and spleen radioactivity with time implies that the nanoparticles are broken down and cleared. This is an important finding, as it shows that the nanoparticles can be safely used as a vaccine platform without the risk of prolonged side effects. Furthermore, it demonstrates that technetium carbonyl radiolabeling of our protein-based nanoparticles can be used to evaluate their pharmacokinetic properties in vivo.

Metastasis-Related Signature for Clinically Predicting Prognosis and Tumor Immune Microenvironment of Osteosarcoma Patients.

Osteosarcoma is the most prevalent clinical malignant bone tumor in adolescents. The prognosis of metastatic osteosarcoma is still very poor. The aim of our study was to investigate the clinical diagnosis and prognostic significance of metastasis related genes (MRGs) in patients with osteosarcoma. Clinical information and RNA sequencing data with osteosarcoma patients were obtained and set as the training set from UCSC databases. GSE21257 were downloaded and chosen as the verification cohort. An eight gene metastasis related risk signature including MYC, TAC4, ABCA4, GADD45GIP1, TNFRSF21, HERC5, MAGEA11, and PDE1B was built to predict the overall survival of osteosarcoma patients. Based on risk assessments, patients were classified into high- and low-risk groups. The high-risk patients had higher risk score and shorter survival time. ROC curves revealed that this risk signature can accurately predict survival times of osteosarcoma patients at the 1-, 2-, 3-, 4- and 5- year. GSEA revealed that MYC targets, E2F targets, mTORC1 signaling, Wnt /ß-catenin signaling and cell cycle were upregulated, and cell adhesion molecules, and primary immunodeficiency were decreased in high-risk group. MRGs were highly linked with the tumor immune microenvironment and ICB response. These results identified that MRGs as a novel prognostic and diagnostic biomarker in osteosarcoma.

Imaging evaluation of blood supply changes after chemotherapy of osteosarcoma and its correlation with tumor necrosis rate.

Background: Analysis of the tumour necrosis rate is an important method to evaluate the effect of neoadjuvant chemotherapy for osteosarcoma. However, at present, there is no specific imaging method to evaluate this effect. The purpose of this study was to evaluate the changes in blood supply after chemotherapy by measuring the CT enhancement rate and to analyse the correlation between the CT enhancement rate and the tumour necrosis rate. Methods: Patients with primary osteosarcoma of the extremities treated in our institute from 2016 to 2017 were analysed retrospectively. In total, 103 eligible patients were enrolled in the study, including 67 males and 36 females, with an average age of 17.7 (6-54) years. Sixty cases had tumour sites in the femur, 25 in the tibia, 10 in the humerus, and eight in other sites. All patients received neoadjuvant chemotherapy including methotrexate, cisplatin + doxorubicin and ifosfamide before surgical treatment. All patients underwent enhanced CT examination of the same tumour site before and after the neoadjuvant chemotherapy protocol. The CT value before and after chemotherapy was measured and the enhancement rate was calculated. The change in the CT enhancement rate after chemotherapy was analysed. Changes in the CT enhancement rate were compared between patients with a tumour necrosis rate greater than 90% and those with one <90%. Results: The average CT enhancement rates before and after chemotherapy were 1.68 (median 1.63, range 1.00-2.51) and 1.39 (median 1.28, range 1.00-2.83), respectively (P < 0.01). The average CT enhancement rate after chemotherapy decreased by 15.0% (median 16.7%, range -27.5-53%): 75 cases exhibited a decrease, three cases remained unchanged, and 25 cases exhibited an increase. The average enhancement rate before chemotherapy was 1.75 (median 1.68, range 1.18-2.51) in the group with a necrosis rate >90% and 1.62 (median 1.52, range 1.00-2.41) in the group with a necrosis rate < 90% (P = 0.068). The average CT enhancement rate after chemotherapy was 1.20 (median 1.21, range 1.00-1.53) in the group with a necrosis rate > 90% and 1.53 (median 1.43, range 1.00-2.83) in the group with a necrosis rate < 90% (P < 0.01). The enhancement rate of the group with a necrosis rate > 90% decreased by 29.0% (median 28%, range -2.3-53%) (P < 0.01); the enhancement rate of the group with a necrosis rate < 90% decreased by 3.8% on average (median 0.7%, range -27.5-44.5%) (P = 0.225). Conclusion: After receiving neoadjuvant chemotherapy, most patients with osteosarcoma of the extremities exhibited reductions in the CT enhancement rate. In cases where the tumour necrosis rate was greater than 90%, the tumour blood supply was significantly reduced. This suggests that imaging evaluations based on the CT enhancement rate can be used as a reference for evaluating the preoperative effect of chemotherapy for osteosarcoma.

Comprehensive genomic analysis of primary bone sarcomas reveals different genetic patterns compared with soft tissue sarcomas.

Introduction: Sarcomas are classified into two types, bone sarcoma and soft tissue sarcoma (STS), which account for approximately 1% of adult solid malignancies and 20% of pediatric solid malignancies. There exist more than 50 subtypes within the two types of sarcoma. Each subtype is highly diverse and characterized by significant variations in morphology and phenotypes. Understanding tumor molecular genetics is helpful in improving the diagnostic accuracy of tumors that have been difficult to classify based on morphology alone or that have overlapping morphological features. The different molecular characteristics of bone sarcoma and STS in China remain poorly understood. Therefore, this study aimed to analyze genomic landscapes and actionable genomic alterations (GAs) as well as tumor mutational burden (TMB), microsatellite instability (MSI), and programmed death ligand-1 (PD-L1) expression among Chinese individuals diagnosed with primary bone sarcomas and STS. Methods: This retrospective study included 145 patients with primary bone sarcomas (n = 75) and STS (n = 70), who were categorized based on the 2020 World Health Organization classification system. Results: Patients diagnosed with bone sarcomas were significantly younger than those diagnosed with STS (p < 0.01). The top 10 frequently altered genes in bone sarcoma and STS were TP53, CDKN2A, CDKN2B, MAP3K1, LRP1B, MDM2, RB1, PTEN, MYC, and CDK4.The EWSR1 fusions exhibited statistically significant differences (p < 0.01) between primary bone sarcoma and STS in terms of their altered genes. Based on the actionable genes defined by OncoKB, actionable GAs was found in 30.7% (23/75) of the patients with bone sarcomas and 35.7% (25/70) of those with STS. There were 4.0% (3/75) patients with bone sarcoma and 4.3% (3/70) patients with STS exhibited high tumor mutational burden (TMB-H) (TMB ≥ 10). There was only one patient with STS exhibited MSI-L, while the remaining cases were microsatellite stable. The positive rate of PD-L1 expression was slightly higher in STS (35.2%) than in bone sarcoma (33.3%), however, this difference did not reach statistical significance. The expression of PD-L1 in STS patients was associated with a poorer prognosis (p = 0.007). Patients with STS had a better prognosis than those with bone sarcoma, but the observed difference did not attain statistical significance (p = 0.21). Amplification of MET and MYC genes were negatively correlated with clinical prognosis in bone tumors (p<0.01). Discussion: In conclusion, bone sarcoma and STS have significantly different clinical and molecular characteristics, suggesting that it is vital to diagnose accurately for clinical treatment. Additionally, comprehensive genetic landscape can provide novel treatment perspectives for primary bone sarcoma and STS. Taking TMB, MSI, PD-L1 expression, and OncoKB definition together into consideration, there are still many patients who have the potential to respond to targeted therapy or immunotherapy.

A Retrospective Observational Study on Disease Characteristics and Treatment Patterns of Giant Cell Tumor of the Bone in China.

Aims: Giant cell tumor of the bone (GCTB) is associated with considerable morbidity. As GCTB epidemiological data for China are limited, this study is aimed at describing the disease characteristics of GCTB in China and establishing the historical context for its treatment before recent advances in treatment options. Methods: The disease characteristics, treatment patterns, and local GCTB recurrence rate after primary surgery for GCTB were evaluated in this single-center, retrospective, noninterventional, observational study of patients treated for GCTB at Ji Shui Tan Hospital, Beijing, from 2009 to 2016 based on medical chart review. Patients with unmet need were defined as those whose surgical treatment was difficult or who had to undergo high-morbidity surgery. Results: Among the 668 patients with a primary GCTB diagnosis, 578 (86.5%) of target lesions were in the extremities, and 89 (13.3%) were in the pelvic or axial bone. Of these, 173 (25.9%) were characterized as having an unmet need. Almost all GCTB patients received surgical treatment at both primary diagnosis (666/668 (99.7%)) and last disease recurrence (196/200 (98.0%)). Additionally, about one-third of patients received nonsurgical treatment at primary diagnosis (205/668 (30.7%)) and disease recurrence (67/200 (33.5%)), with neoadjuvant therapy being the most common treatment. The rate of high-morbidity surgery increased for recurrent disease (65/200 (32.5%)) compared with primary diagnosis (111/668 (16.6%)). The 2-year cumulative incidence of postoperative disease recurrence was 29.2%, in line with rates observed in prior studies. Conclusion: As many patients with primary and recurrent disease received high-morbidity surgery, more effective treatments are needed.

Genomic and transcriptomic characterization of pre-operative chemotherapy response in patients with osteosarcoma.

Osteosarcoma is a heterogeneous disease with regard to its chemotherapy response and clinical outcomes. This study aims to investigate the genomic and transcriptomic characteristics related to pre-operative chemotherapy response. Samples from 25 osteosarcoma patients were collected to perform both whole exome and transcriptome sequencing. Osteosarcoma had significant amount of chromosomal copy number variants (CNVs). Chemotherapy responders showed the higher chromosomal CNV burden than non-responders (p = 0.0775), but the difference was not significant. The percentage of COSMIC signature 3, associated with homologous recombination repair deficiency, was higher in responders (56%) than in non-responders (45%). Transcriptomic analysis suggested that 11 genes were significantly up-regulated in responders and 18 genes were up-regulated in non-responders. Both GSEA and KEGG enrichment analysis indicted that four pathways related to cardiomyopathy were up-regulated in responders, while neuroactive ligand - receptor interaction was up-regulated in non-responders. Finally, a previously published chemoresistant model was validated using our dataset, with the area under the curve of 0.796 (95% CI, 0.583-1.000). Osteosarcoma had the heterogeneous mutational profile with frequent occurrence of CNVs. Transcriptomic analysis identified several signaling pathways associated with chemotherapy responsiveness to osteosarcoma. Transcriptomic signatures provides a potential research direction for predicting the chemotherapy response.

[Short-term effectiveness of orthopedic robot-assisted resection for osteoid osteoma].

Objective: To investigate short-term effectiveness and clinical application advantages of orthopedic robot-assisted resection for osteoid osteoma compared with traditional open surgery. Methods: A retrospective analysis was conducted on clinical data of 48 osteoid osteoma patients who met the selection criteria between July 2022 and April 2023. Among them, 23 patients underwent orthopedic robot-assisted resection (robot-assisted surgery group), and 25 patients received traditional open surgery (traditional surgery group). There was no significant difference ( P>0.05) in gender, age, disease duration, lesion location and size, and preoperative visual analogue scale (VAS) score, and musculoskeletal tumor society (MSTS) score between the two groups. The surgical time, intraoperative blood loss, intraoperative lesion localization time, initial localization success rate, infection, and recurrence were recorded and compared. VAS scores before surgery and at 24 hours, 1, 3, 6, and 9 months after surgery and MSTS score before surgery and at 3 months after surgery were assessed. Results: All patients completed the surgery successfully, with no significant difference in surgical time between the two groups ( P>0.05). Compared to the traditional surgery group, the robot-assisted surgery group had less intraoperative blood loss, shorter lesion localization time, and shorter hospitalization time, with significant differences ( P<0.05). The initial localization success rate was higher in the robot-assisted surgery group than in the traditional surgery group, but the difference between the two groups was not significant ( P>0.05). All patients in both groups were followed up, with the follow-up time of 3-12 months in the robot-assisted surgery group (median, 6 months) and 3-14 months in the traditional surgery group (median, 6 months). The postoperative MSTS scores of both groups improved significantly when compared to those before surgery ( P<0.05), but there was no significant difference in the changes in MSTS scores between the two groups ( P>0.05). The postoperative VAS scores of both groups showed a gradually decreasing trend over time ( P<0.05), but there was no significant difference between the two groups after surgery ( P>0.05). During follow-up, except for 1 case of postoperative infection in the traditional surgery group, there was no infections or recurrences in other cases. There was no significant difference in the incidence of postoperative infection between the two groups ( P>0.05). Conclusion: Orthopedic robot-assisted osteoid osteoma resection achieves similar short-term effectiveness when compared to traditional open surgery, with shorter lesion localization time.

Optimizing the refolding conditions of self-assembling polypeptide nanoparticles that serve as repetitive antigen display systems.

Nanoparticles show great promise as potent vaccine candidates since they are readily taken up by the antigen presenting cells of the immune system. The particle size and the density of the B cell epitopes on the surface of the particles greatly influences the strength of the humoral immune response. We have developed a novel type of nanoparticle composed of peptide building blocks (Raman et al., 2006) and have used such particles to design vaccines against malaria and SARS (Kaba et al., 2009; Pimentel et al., 2009). Here we investigate the biophysical properties and the refolding conditions of a prototype of these self-assembling polypeptide nanoparticles (SAPNs). SAPNs are formed from a peptide containing a pentameric and a trimeric coiled-coil domain. At near physiological conditions the peptide self-assembles into about 27 nm, roughly spherical SAPNs. The average size of the SAPNs increases with the salt concentration. The optimal pH for their formation is between 7.5 and 8.5, while aggregation occurs at lower and higher values. A glycerol concentration of about 5% v/v is required for the formation of SAPNs with regular spherical shapes. These studies will help to optimize the immunological properties of SAPNs.

Encapsulation of gold nanoparticles into self-assembling protein nanoparticles.

BACKGROUND: Gold nanoparticles are useful tools for biological applications due to their attractive physical and chemical properties. Their applications can be further expanded when they are functionalized with biological molecules. The biological molecules not only provide the interfaces for interactions between nanoparticles and biological environment, but also contribute their biological functions to the nanoparticles. Therefore, we used self-assembling protein nanoparticles (SAPNs) to encapsulate gold nanoparticles. The protein nanoparticles are formed upon self-assembly of a protein chain that is composed of a pentameric coiled-coil domain at the N-terminus and trimeric coiled-coil domain at the C-terminus. The self-assembling protein nanoparticles form a central cavity of about 10 nm in size, which is ideal for the encapsulation of gold nanoparticles with similar sizes. RESULTS: We have used SAPNs to encapsulate several commercially available gold nanoparticles. The hydrodynamic size and the surface coating of gold nanoparticles are two important factors influencing successful encapsulation by the SAPNs. Gold nanoparticles with a hydrodynamic size of less than 15 nm can successfully be encapsulated. Gold nanoparticles with citrate coating appear to have stronger interactions with the proteins, which can interfere with the formation of regular protein nanoparticles. Upon encapsulation gold nanoparticles with polymer coating interfere less strongly with the ability of the SAPNs to assemble into nanoparticles. Although the central cavity of the SAPNs carries an overall charge, the electrostatic interaction appears to be less critical for the efficient encapsulation of gold nanoparticles into the protein nanoparticles. CONCLUSIONS: The SAPNs can be used to encapsulate gold nanoparticles. The SAPNs can be further functionalized by engineering functional peptides or proteins to either their N- or C-termini. Therefore encapsulation of gold nanoparticles into SAPNs can provide a useful platform to generate a multifunctional biodevices.

Study of imaging changes following preoperative denosumab for giant cell tumor of bone.

BACKGROUND: The changes in the characteristics of the tumor blood supply of giant cell tumor of bone over time after treatment with denosumab remain unclear. The purpose of this study was to evaluate the change in the blood supply imaging characteristics of giant cell tumor of bone after preoperative denosumab treatment and to provide evidence for evaluating the reasonable time for preoperative treatment. METHODS: A total of 59 patients with giant cell tumor of bone who were treated in our hospital from 2014 to 2019 were enrolled in the study. All patients underwent enhanced CT examination of the tumor site before denosumab treatment and every month after treatment. The plain CT value and enhanced CT value of the tumor were measured, and the CT enhancement rate of the tumor was calculated. The change in the CT enhancement rate of the tumor over time after denosumab treatment was analyzed. RESULTS: The average tumor enhancement rates were 2.14 (1.22-4.05), 1.60 (1.12-2.53), 1.38 (1.02-2.24), and 1.25 (1-2.11) before denosumab treatment and one month, three months, and six months after treatment, respectively. After denosumab treatment, the average monthly CT enhancement rate decreased as follows: 0.54 (25.2%) in the first month, 0.11 (5.15%) in the second to third months, and 0.04 (1.87%) in the fourth to sixth months. The tumor enhancement rate was no longer significantly reduced three months post-treatment. There was a significant correlation between the reduction in the CT enhancement rate and the initial CT enhancement rate (P = 0.000). CONCLUSION: The preoperative application of denosumab can reduce tumor blood supply. The decrease in the blood supply is the most significant in the initial stage of treatment. Following treatment, the decrease in the blood supply gradually reduces over time. Therefore, for the purpose of reducing intra-operative bleeding and facilitating surgery, application of denosumab treatment is not recommended more than three months before surgery.