Collagen and derivatives-based materials as substrates for the establishment of glioblastoma organoids.

Glioblastoma (GBM) is a common primary brain malignancy known for its ability to invade the brain, resistance to chemotherapy and radiotherapy, tendency to recur frequently, and unfavorable prognosis. Attempts have been undertaken to create 2D and 3D models, such as glioblastoma organoids (GBOs), to recapitulate the glioma microenvironment, explore tumor biology, and develop efficient therapies. However, these models have limitations and are unable to fully recapitulate the complex networks formed by the glioma microenvironment that promote tumor cell growth, invasion, treatment resistance, and immune escape. Therefore, it is necessary to develop advanced experimental models that could better simulate clinical physiology. Here, we review recent advances in natural biomaterials (mainly focus on collagen and its derivatives)-based GBO models, as in vitro experimental platforms to simulate GBM tumor biology and response to tested drugs. Special attention will be given to 3D models that use collagen, gelatin, further modified derivatives, and composite biomaterials (e.g., with other natural or synthetic polymers) as substrates. Application of these collagen/derivatives-constructed GBOs incorporate the physical as well as chemical characteristics of the GBM microenvironment. A perspective on future research is given in terms of current issues. Generally, natural materials based on collagen/derivatives (monomers or composites) are expected to enrich the toolbox of GBO modeling substrates and potentially help to overcome the limitations of existing models.

Polyurethane scaffold-based 3D lung cancer model recapitulates in vivo tumor biological behavior for nanoparticulate drug screening.

Lung cancer is the leading cause of cancer mortality worldwide. Preclinical studies in lung cancer hold the promise of screening for effective antitumor agents, but mechanistic studies and drug discovery based on 2D cell models have a high failure rate in getting to the clinic. Thus, there is an urgent need to explore more reliable and effective in vitro lung cancer models. Here, we prepared a series of three-dimensional (3D) waterborne biodegradable polyurethane (WBPU) scaffolds as substrates to establish biomimetic tumor models in vitro. These 3D WBPU scaffolds were porous and could absorb large amounts of free water, facilitating the exchange of substances (nutrients and metabolic waste) and cell growth. The scaffolds at wet state could simulate the mechanics (elastic modulus ∼1.9 kPa) and morphology (porous structures) of lung tissue and exhibit good biocompatibility. A549 lung cancer cells showed adherent growth pattern and rapidly formed 3D spheroids on WBPU scaffolds. Our results showed that the scaffold-based 3D lung cancer model promoted the expression of anti-apoptotic and epithelial-mesenchymal transition-related genes, giving it a more moderate growth and adhesion pattern compared to 2D cells. In addition, WBPU scaffold-established 3D lung cancer model revealed a closer expression of proteins to in vivo tumor, including tumor stem cell markers, cell proliferation, apoptosis, invasion and tumor resistance proteins. Based on these features, we further demonstrated that the 3D lung cancer model established by the WBPU scaffold was very similar to the in vivo tumor in terms of both resistance and tolerance to nanoparticulate drugs. Taken together, WBPU scaffold-based lung cancer model could better mimic the growth, microenvironment and drug response of tumor in vivo. This emerging 3D culture system holds promise to shorten the formulation cycle of individualized treatments and reduce the use of animals while providing valid research data for clinical trials.

Porous Three-Dimensional Polyurethane Scaffolds Promote Scar-Free Endogenous Regeneration After Acute Brain Hemorrhage.

Intracerebral hemorrhage (ICH) is the most lethal subtype of stroke and is associated with significant morbidity and mortality. Despite advances in the clinical treatment of ICH, limited progress has been made regarding endogenous brain regeneration after ICH. Failure of brain regeneration is mainly attributed to the inhibitive regenerative microenvironment caused by secondary injury after ICH. In this study, we investigated a three-dimensional biodegradable waterborne polyurethane (BWPU) scaffold as a tool to promote brain regeneration after ICH. After implantation into the cavity following hematoma evacuation, these implanted scaffolds could act as a reservoir; store a series of necrotic debris, cytokines, and chemokines; and attract microglia/macrophages to their pores. Subsequently, these microglia/macrophages were polarized into the M1-like subtype to eliminate these substances. This process disperses M1-like immune cells and prevents the formation of dense glial scar-free structures after ICH. Inflammatory cells in scaffolds include scar-free secreted growth factors and extracellular matrix (ECM) proteins, and further induce a M2-like immune cells enriched regeneration-predominant microenvironment to promote endogenous brain regeneration with functional recovery. In summary, in this work, we have revealed the potential and mechanism of the BWPU scaffold as a tool to promote endogenous brain tissue regeneration after ICH.

Case Report: Successful Use of BRAF/MEK Inhibitors in Aggressive BRAF-mutant Craniopharyngioma.

BACKGROUND: Although a benign intracranial tumor, craniopharyngioma treatment has always been considered a challenging clinical problem. Recently, BRAF V600E mutation in the pathogenesis of papillary craniopharyngioma (PCP) has been further revealed. Thus, BRAF inhibitors (BRAFi) serve as an applicable treatment for patients with PCP. METHODS: Two patients with recurrent PCP were treated with combined BRAFi dabrafenib (150 mg, orally twice daily) and MEK inhibitors (MEKi) trametinib (2 mg, orally twice daily). A follow-up exceeding 2 years was conducted. We meticulously scrutinized the treatment's safety and efficacy profiles by delving into existing literature. RESULTS: One patient harboring a solid tumor achieved a complete tumor response devoid of any adverse events and encountered no recurrence over 2 years subsequent to discontinuation. Moreover, within a mere month of commencing targeted therapy, the tumor demonstrated observable shrinkage. This finding substantiates the considerable potential inherent in targeted therapy for PCP cases marked by the somatic BRAF V600E mutation. CONCLUSIONS: Under specific conditions, individuals diagnosed with PCP can attain a complete tumor response following combined treatment with BRAFi/MEKi.

Identification of lncRNAs associated with T cells as potential biomarkers and therapeutic targets in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is the most common and deadliest subtype of lung cancer. To select more targeted and effective treatments for individuals, further advances in classifying LUAD are urgently needed. The number, type, and function of T cells in the tumor microenvironment (TME) determine the progression and treatment response of LUAD. Long noncoding RNAs (lncRNAs), may regulate T cell differentiation, development, and activation. Thus, our aim was to identify T cell-related lncRNAs (T cell-Lncs) in LUAD and to investigate whether T cell-Lncs could serve as potential stratifiers and therapeutic targets. Seven T cell-Lncs were identified to further establish the T cell-related lncRNA risk score (TRS) in LUAD. Low TRS individuals were characterized by robust immune status, fewer genomic alterations, and remarkably longer survival than high TRS individuals. The excellent accuracy of TRS in predicting overall survival (OS) was validated in the TCGA-LUAD training cohort and the GEO-LUAD validation cohort. Our data demonstrated the favorable predictive power of the TRS-based nomogram, which had important clinical significance in estimating the survival probability for individuals. In addition, individuals with low TRS could respond better to chemotherapy and immunotherapy than those with high TRS. LINC00525 was identified as a valuable study target, and the ability of LUAD to proliferate or invade was significantly attenuated by downregulation of LINC00525. In conclusion, the TRS established by T cell-Lncs could unambiguously classify LUAD patients, predict their prognosis and guide their management. Moreover, our identified T cell-Lncs could provide potential therapeutic targets for LUAD.

Single-cell RNA sequencing highlights intratumor heterogeneity and intercellular network featured in adamantinomatous craniopharyngioma.

Despite improvements in microscopically neurosurgical techniques made in recent years, the prognosis of adamantinomatous craniopharyngioma (ACP) is still unsatisfactory. Little is known about cellular atlas and biological features of ACP. Here, we carried out integrative analysis of 44,038 single-cell transcriptome profiles to characterize the landscape of intratumoral heterogeneity and tumor microenvironment (TME) in ACP. Four major neoplastic cell states with distinctive expression signatures were defined, which further revealed the histopathological features and elucidated unknown cellular atlas of ACP. Pseudotime analyses suggested potential evolutionary trajectories between specific neoplastic cell states. Notably, a distinct oligodendrocyte lineage was identified in ACP, which was associated with immunological infiltration and neural damage. In addition, we described a tumor-centric regulatory network based on intercellular communication in TME. Together, our findings represent a unique resource for deciphering tumor heterogeneity of ACP, which will improve clinical diagnosis and treatment strategies.

Biodegradable polyurethane-incorporating decellularized spinal cord matrix scaffolds enhance Schwann cell reprogramming to promote peripheral nerve repair.

Decellularized extracellular matrix (dECM) nerve guide conduits (NGCs) are a promising strategy to replace autogenous nerve grafting for the treatment of peripheral nerve system (PNS) injury. However, dECM conduits with mechanical properties that match those of peripheral nerves are yet to be well developed. Herein, we developed polyurethane-based NGCs incorporating decellularized spinal cord (BWPU-DSC NGCs) to repair peripheral nerves. BWPU-DSC NGCs have an inner three-dimensional micro-nanostructure. The mechanical properties of BWPU-DSC NGCs were similar to those of polyurethane NGCs, which were proven to promote peripheral nerve regeneration. An in vitro study indicated that BWPU-DSC NGCs could boost the proliferation and growth of cell processes in Schwann and neuron-like cells. In a rat sciatic nerve transected injury model, BWPU-DSC NGCs exhibited a dramatic increase in nerve repair, similar to that obtained by the current gold standard autograft implantation at only 6 weeks post-implantation, whereas polyurethane NGCs still displayed incomplete nerve repair. Histological analysis revealed that BWPU-DSC NGCs could induce the reprogramming of Schwann cells to promote axon regeneration and remyelination. Moreover, reprogrammed Schwann cells together with BWPU-DSC NGCs had anti-inflammatory effects and altered the activation state of macrophages to M2 phenotypes to enhance PNS regeneration. In this study, we provided a strategy to prepare polyurethane-based dECM NGCs enriched with bioactive molecules to promote PNS regeneration.

Expression and clinical significance of VISTA, B7-H3, and PD-L1 in glioma.

Immune checkpoint (IC) therapy has led to a breakthrough in cancer treatment. However, the interaction of ICs is controversial in glioma. We detected features of ICs using transcriptome data and a multicolor immunofluorescence assay. We discovered that B7-H3 increased with grade and age and predicted worse overall survival (OS) at the transcriptional and proteomic levels. VISTA and PD-L1 were associated with OS and grade at the RNA level. At the protein level, VISTA was primarily expressed in tumor cells and TAMs. B7-H3 and VISTA were positively correlated with PD-L1. There was a strong correlation between PD-L1 and CD3 and between VISTA and IBA-1. PD-L1 was coexpressed with T cells. VISTA was coexpressed with TAMs. In T cells, we found a strong correlation in ICs, which worsened in TAMs and tumor cells. In conclusion, B7-H3 is a vital prognostic target for immunotherapy. We provided a potential mechanism for the immunosuppressive microenvironment in glioma.

Characterization of novel CTNNB1 mutation in Craniopharyngioma by whole-genome sequencing.

BACKGROUND: Craniopharyngioma (CP) is rare histologically benign but clinically challenging tumor because of its intimate relationship with the critical structure in the central brain. CP can be divided into two major histologic subtypes: adamantinomatous-type CP (ACP) and papillary-type CP (PCP). Although some genetic aberrations for both categories have been revealed in previous studies, the complete spectrum of genetic changes of this tumor remains unknown. METHODS: In this study, we conducted whole genome sequencing (WGS) on twenty-six CPs including 16 ACPs and 10 PCPs together with their matched blood samples. Somatic variants (SNVs, InDels, SVs and CNVs) were identified and mutational signatures were characterized for each patient. We investigated the impact of a novel CTNNB1 mutant on its protein stability, ubiquitination and Wnt pathway activity. Cell proliferation ability of the CTNNB1 mutant in ACP primary cells was additionally analyzed by CCK8 and colony formation assays. RESULTS: We found that CPs had showed less complexity with fewer somatic mutations compared with malignant tumors. Moreover, mutations in CTNNB1 (68.75% of ACP) and BRAF V600E (70.00% of PCP) are mutually exclusive in ACP and PCP, consolidating that the driving roles of these two genes in ACP and PCP, respectively. A novel mutation in the exon 3 of CTNNB1 which compromised both a transversion and in-frame deletion was identified in ACP. This mutation was experimentally validated to confer ß-catenin increased stability by inhibiting its ubiquitination, thus activating Wnt-signaling pathway and promoting cell proliferation. CONCLUSIONS: Whole genome landscape for CP was revealed by WGS analysis, and a novel mutation in the exon 3 of CTNNB1 was identified. This novel mutation activates Wnt-signaling pathway through increasing the stability of ß-catenin. Our findings provided us with more comprehensive insight into the spectrum of genetic alterations in CP.

Biodegradable polyurethane nerve guide conduits with different moduli influence axon regeneration in transected peripheral nerve injury.

Nerve guide conduits (NGCs) can replace autogenous nerve grafting in the treatment of peripheral nerve system (PNS) injury. However, the modulus of polyurethane NGCs that affects the outcome of PNS repair has been rarely elucidated in vivo. In this study, we developed biodegradable waterborne polyurethane (BWPU) NGCs with an outer BWPU membrane and an inner three-dimensional scaffold structure. The mechanical properties of BWPU NGCs can be modified by adjusting the molar content of polyethylene glycol (PEG) in the soft segments within the BWPU. Two types of BWPU NGCs with different moduli were prepared, containing 17% and 25% PEG in BWPU (termed as BWPU 17 NGCs and BWPU 25 NGCs, respectively). In rat sciatic nerves with 10-mm transected injury, mechanically stronger BWPU 17 NGCs exhibited superior nerve repair, which was similar to that obtained by the current gold standard autograft implantation, whereas weaker BWPU 25 NGCs displayed an unsatisfactory effect. Histological results revealed that both BWPU NGCs had anti-inflammatory effects and altered the activation state of macrophages to M2 phenotypes to enhance PNS regeneration. The analysis of growth-associated protein 43 expression, which regulates axon growth, revealed that the mechanical properties of BWPU NGCs influence the outcome of PNS regeneration by affecting the formation and extension of axons. These findings suggest that the mechanical properties of NGCs could play a key role in regulating PNS repair and should be considered in future biomaterial NGC designs.

Impact of neutrophil-lymphocyte ratio on long-term outcome in patients with craniopharyngioma.

Neutrophil-lymphocyte ratio (NLR) is a poor prognostic factor in many tumors including glioblastoma multiforme (GBM), colorectal, and prostate cancer. The aim of this study was to investigate the prognostic value of preoperative NLR in patients with craniopharyngioma.Around 149 patients of craniopharyngioma surgically were treated at the Department of Neurosurgery, West China Hospital from January 2008 to December 2010, including 84 males and 65 females aged from 6 to 70 years were retrospectively reviewed, and preoperative NLR was analyzed. Overall survival (OS), progression free survival (PFS), and quality of life (QOL) were evaluated.The 5-year OS and PFS rates were 81.21% and 75.84%. Preoperative NLR was significantly correlated with OS (HR = 1.44, 95% CI 1.16-1.79, P = .001) and PFS (HR = 1.46, 95% CI 1.22-1.74, P < .001). The best cut-off value of NLR was found to be 4 based on the receiver operator characteristics (ROC) curve. Patients with NLR ≥4 had a significantly worse QOL (P = .039), lower OS rate (P = .009), and PFS rate (P < .001).Preoperative NLR may be a simple, readily available, and valid predictor of long-term outcome in craniopharyngioma. We suggest that the NLR can provide effective guidance to neurosurgeons for more information about the tumor and prognostic evaluation.

Macrophage Polarization in Response to Varying Pore Sizes of 3D Polyurethane Scaffolds.

Activated macrophages dominate the progression of foreign-body response (FBR) and may be in a bimodal state, which determines the fate of biomaterials postimplantation. The purpose of this study was to investigate the phenotypic profile of macrophages polarized by waterborne biodegradable polyurethane (WBPU) scaffolds with different pore diameters (PU8, PU12, and PU16) both in vitro and in vivo. The results demonstrated that WBPU scaffolds with smaller pore sizes promoted the polarization of RAW 264.7 cells towards an M1 phenotypic profile at the early stage (24 and 48 h of in vitro cultivation), indicating a pro-inflammatory response. After being implanted subcutaneously, however, the WBPU scaffolds recruited more macrophages over time and polarized them towards an M2 phenotype on Day 3 and 14, presenting an anti-inflammatory response and tissue repair. When the internal pores were filled up (on Day 30 of implantation), the interaction between the scaffolds and macrophages decreased, indicating an endpoint of tissue repair. In general, WBPU scaffolds with tunable internal pore sizes have potential application prospects in the field of tissue engineering.

Applications of Nanomaterials in Radiotherapy for Malignant Tumors.

Malignant tumors are tremendous heath problems facing by the medical world. In order to achieve the purpose of curing malignant tumor, numerous therapeutic strategies have been developed. Radiotherapy is one of the main therapeutic strategies for malignant tumors. Current imaging strategies cannot display exact infiltrating margins, radio-resistance generated by irradiated tissue, and intercurrent damage to healthy tissues during radiotherapy. Therefore, novel strategies to solve these problems are urgently needed. Nanomaterials have specific physical and biological properties that can help clinician to distinguish margins of infiltrating tumors as a novel contrast agent. Besides, nanoparticles can significantly enhance the effect of radiotherapy by generating reactive oxygen species (ROS) or influence cell cycle. In addition, nanomaterials can also help in diminishing the intercurrent damage caused by radiotherapy. So nanomaterials have very promising prospect in the radiotherapy of malignant tumors. This review mainly focuses on the applications of nanomaterials in radiotherapy for malignant tumors; especially it applies to lesion imaging and their radiosensitizing effects.