Mesenchymal stem cells in craniofacial reconstruction: a comprehensive review.

Craniofacial reconstruction faces many challenges, including high complexity, strong specificity, severe injury, irregular and complex wounds, and high risk of bleeding. Traditionally, the "gold standard" for treating craniofacial bone defects has been tissue transplantation, which involves the transplantation of bone, cartilage, skin, and other tissues from other parts of the body. However, the shape of craniofacial bone and cartilage structures varies greatly and is distinctly different from ordinary long bones. Craniofacial bones originate from the neural crest, while long bones originate from the mesoderm. These factors contribute to the poor effectiveness of tissue transplantation in repairing craniofacial defects. Autologous mesenchymal stem cell transplantation exhibits excellent pluripotency, low immunogenicity, and minimally invasive properties, and is considered a potential alternative to tissue transplantation for treating craniofacial defects. Researchers have found that both craniofacial-specific mesenchymal stem cells and mesenchymal stem cells from other parts of the body have significant effects on the restoration and reconstruction of craniofacial bones, cartilage, wounds, and adipose tissue. In addition, the continuous development and application of tissue engineering technology provide new ideas for craniofacial repair. With the continuous exploration of mesenchymal stem cells by researchers and the continuous development of tissue engineering technology, the use of autologous mesenchymal stem cell transplantation for craniofacial reconstruction has gradually been accepted and promoted. This article will review the applications of various types of mesenchymal stem cells and related tissue engineering in craniofacial repair and reconstruction.

Refracture-related bone transport of tibia: technical notes and preliminary clinical results in nineteen cases.

PURPOSE: Refracture is one of the main complications of bone transport, which brings additional physical and mental burden to surgeries and patients. We aimed to raise a new classification system of refracture-related bone transport based on the Simpson classification and to present our experience on treatment. METHODS: This retrospective analysis included 19 patients with refracture-related bone transport (average age of 37.7 years; 18 men). We developed a modified Simpson classification system to assist decision-making (conservative versus surgical). The ASAMI criteria were used to assess the outcomes at last follow-up. RESULTS: The mean follow-up was 12.3 ± 3.2 months. Complete union was achieved in all patients, with no reinfection. Based on the modified Simpson classification, refracture was Ia type (within regeneration area) in three cases, Ib (collapsed fracture at the regeneration area) in one case, Ic (stress fracture) in three cases, II (at the junction between the regenerate and original bone) in one case, III (at the docking site) in nine cases, and V (at distant site) in two cases. Refracture was managed conservatively in six cases and surgically in 13 cases. Average time to bone union was 2.8 ± 1.2 months in the conservative group versus 4.4 ± 1.4 months in the surgery group. Assessment at the final follow-up using the ASAMI criteria revealed excellent bone result in all patients, excellent functional results in six patients (31.6%), and good functional results in 13 patients. CONCLUSIONS: The modified Simpson classification could include refracture at the docking site and stress fracture in the regeneration zone and provide some guidance in determining the appropriate treatment strategy.

Association Between Peritoneal Carcinomatosis Index (PCI) Assessed by CT and Pathological Parameters and Short-Term Prognosis of Rectal Cancer.

Objective: The study aimed at explore the correlation between the CT-based Peritoneal Carcinomatosis Index (PCI) and pathological parameters of rectal cancer, as well as the correlation with short-term postoperative prognosis. Methods: A retrospective analysis was performed on 198 rectal cancer patients treated in our institution from January 2017 to December 2022. Based on preoperative CT-PCI, patients were classified into a normal and low CT-PCI groups. Baseline characteristics and short-term postoperative outcomes were compared between the two groups. Univariate and Multivariable logistic regression analyses were conducted to ascertain the independent risk factors for postoperative complications (Clavien-Dindo classification ≥ Grade II) following neoadjuvant treatment and radical rectal cancer surgery. Results: There were significant statistical differences between the two groups regarding age, ASA score, and surgical method (P < .05). Variations in overall postoperative complications and complications of Grade II or higher among patients with differing preoperative CT-PCI were statistically significant (P < .05). No significant statistical difference was found in the time to first liquid intake post-surgery between the preoperative low CT-PCI group and the normal CT-PCI group (P > .05); however, differences in the time to first flatus, duration of postoperative hospital stay, and total hospital expenditure were statistically meaningful (P < .05). Multivariate logistic regression revealed that CT-PCI (OR=2.254) was an influential factor for postoperative complications (Clavien-Dindo classification ≥ Grade II) (P < .05). The ROC curve demonstrated an AUC of 0.854 for CT-PCI in predicting postoperative complications (Clavien-Dindo classification ≥ Grade II). Conclusion: Preoperative CT-PCI may be utilized to evaluate the short-term prognosis of patients who undergo radical surgery for rectal cancer after neoadjuvant therapy. This evaluation assists in guiding clinical diagnostic and therapeutic decision-making, allowing for prompt interventions and enhancing short-term patient outcomes.

The role of integrin αvß3 in biphasic calcium phosphate ceramics mediated M2 Macrophage polarization and the resultant osteoinduction.

Calcium phosphate ceramics-based biomaterials were reported to have good biocompatibility and osteoinductivity and have been widely applied for bone defect repair and regeneration. However, the mechanism of their osteoinductivity is still unclear. In our study, we established an ectopic bone formation in vivo model and an in vitro macrophage cell co-culture system with calcium phosphate ceramics to investigate the effect of biphasic calcium phosphate on osteogenesis via regulating macrophage M1/M2 polarization. Our micro-CT data suggested that biphasic calcium phosphate had significant osteoinductivity, and the fluorescence co-localization detection found increased F4/80+/integrin αvß3+ macrophages surrounding the biphasic calcium phosphate scaffolds. Besides, our study also revealed that biphasic calcium phosphate promoted M2 polarization of macrophages via upregulating integrin αvß3 expression compared to tricalcium phosphate, and the increased M2 macrophages could subsequently augment the osteogenic differentiation of MSCs in a TGFß mediated manner. In conclusion, we demonstrated that macrophages subjected to biphasic calcium phosphate could polarize toward M2 phenotype via triggering integrin αvß3 and secrete TGFß to increase the osteogenesis of MSCs, which subsequently enhances bone regeneration.

The role of zinc finger proteins in the fate determination of mesenchymal stem cells during osteogenic and adipogenic differentiation.

Zinc finger proteins (ZFPs) constitute a crucial group of transcription factors widely present in various organisms. They act as transcription factors, nucleases, and RNA-binding proteins, playing significant roles in cell differentiation, growth, and development. With extensive research on ZFPs, their roles in the determination of mesenchymal stem cells (MSCs) fate during osteogenic and adipogenic differentiation processes have become increasingly clear. ZFP521, for instance, is identified as an inhibitor of the Wnt signaling pathway and RUNX2's transcriptional activity, effectively suppressing osteogenic differentiation. Moreover, ZFP217 contributes to the inhibition of adipogenic differentiation by reducing the M6A level of the cell cycle regulator cyclin D1 (CCND1). In addition, other ZFPs can also influence the fate of mesenchymal stem cells (MSCs) during osteogenic and adipogenic differentiation through various signaling pathways, transcription factors, and epigenetic controls, participating in the subsequent differentiation and maturation of precursor cells. Given the prevalent occurrence of osteoporosis, obesity, and related metabolic disorders, a comprehensive understanding of the regulatory mechanisms balancing bone and fat metabolism is essential, with a particular focus on the fate determination of MSCs in osteogenic and adipogenic differentiation. In this review, we provide a detailed summary of how zinc finger proteins influence the osteogenic and adipogenic differentiation of MSCs through different signaling pathways, transcription factors, and epigenetic mechanisms. Additionally, we outline the regulatory mechanisms of ZFPs in controlling osteogenic and adipogenic differentiation based on various stages of MSC differentiation.

Mild photothermal therapy assist in promoting bone repair: Related mechanism and materials.

Achieving precision treatment in bone tissue engineering (BTE) remains a challenge. Photothermal therapy (PTT), as a form of precision therapy, has been extensively investigated for its safety and efficacy. It has demonstrated significant potential in the treatment of orthopedic diseases such as bone tumors, postoperative infections and osteoarthritis. However, the high temperatures associated with PTT can lead to certain limitations and drawbacks. In recent years, researchers have explored the use of biomaterials for mild photothermal therapy (MPT), which offers a promising approach for addressing these limitations. This review provides a comprehensive overview of the mechanisms underlying MPT and presents a compilation of photothermal agents and their utilization strategies for bone tissue repair. Additionally, the paper discusses the future prospects of MPT-assisted bone tissue regeneration, aiming to provide insights and recommendations for optimizing material design in this field.

Long non-coding RNA APDC plays important regulatory roles in metabolism of bone and adipose tissues.

The long noncoding RNA (lncR) ANRIL in the human genome is an established genetic risk factor for atherosclerosis, periodontitis, diabetes, and cancer. However, the regulatory role of lncR-ANRIL in bone and adipose tissue metabolism remains unclear. To elucidate the function of lncRNA ANRIL in a mouse model, we investigated its ortholog, AK148321 (referred to as lncR-APDC), located on chr4 of the mouse genome, which is hypothesized to have similar biological functions to ANRIL. We initially revealed that lncR-APDC in mouse bone marrow cells (BMSCs) and lncR-ANRIL in human osteoblasts (hFOBs) are both increased during early osteogenesis. Subsequently, we examined the osteogenesis, adipogenesis, osteoclastogenesis function with lncR-APDC deletion/overexpression cell models. In vivo, we compared the phenotypic differences in bone and adipose tissue between APDC-KO and wild-type mice. Our findings demonstrated that lncR-APDC deficiency impaired osteogenesis while promoting adipogenesis and osteoclastogenesis. Conversely, the overexpression of lncR-APDC stimulated osteogenesis, but impaired adipogenesis and osteoclastogenesis. Furthermore, KDM6B was downregulated with lncR-APDC deficiency and upregulated with overexpression. Through binding-site analysis, we identified miR-99a as a potential target of lncR-APDC. The results suggest that lncR-APDC exerts its osteogenic function via miR-99a/KDM6B/Hox pathways. Additionally, osteoclasto-osteogenic imbalance was mediated by lncR-APDC through MAPK/p38 and TLR4/MyD88 activation. These findings highlight the pivotal role of lncR-APDC as a key regulator in bone and fat tissue metabolism. It shows potential therapeutic for addressing imbalances in osteogenesis, adipogenesis, and osteoclastogenesis.

Metal ions: the unfading stars of bone regeneration-from bone metabolism regulation to biomaterial applications.

In recent years, bone regeneration has emerged as a remarkable field that offers promising guidance for treating bone-related diseases, such as bone defects, bone infections, and osteosarcoma. Among various bone regeneration approaches, the metal ion-based strategy has surfaced as a prospective candidate approach owing to the extensive regulatory role of metal ions in bone metabolism and the diversity of corresponding delivery strategies. Various metal ions can promote bone regeneration through three primary strategies: balancing the effects of osteoblasts and osteoclasts, regulating the immune microenvironment, and promoting bone angiogenesis. In the meantime, the complex molecular mechanisms behind these strategies are being consistently explored. Moreover, the accelerated development of biomaterials broadens the prospect of metal ions applied to bone regeneration. This review highlights the potential of metal ions for bone regeneration and their underlying mechanisms. We propose that future investigations focus on refining the clinical utilization of metal ions using both mechanistic inquiry and materials engineering to bolster the clinical effectiveness of metal ion-based approaches for bone regeneration.

The induction of ferroptosis by KLF11/NCOA4 axis: the inhibitory role in clear cell renal cell carcinoma.

Ferroptosis is a form of cell death and has great potential application in the treatment of many cancers, including clear cell renal cell carcinoma (ccRCC). Herein, we identified the essential roles of Krüppel-like factor 11 (KLF11) in suppressing the progression of ccRCC. By analyzing mRNA expression data from the Gene Expression Omnibus (GEO) database, we found that KLF11 was a significantly downregulated gene in ccRCC tissues. The results of subsequent functional assays verified that KLF11 played an antiproliferative role in ccRCC cells and xenograft tumors. Furthermore, gene set enrichment analysis indicated that ferroptosis was involved in ccRCC development, and correlation analysis revealed that KLF11 was positively related to ferroptosis drivers. We also found that KLF11 promoted ferroptosis in ccRCC by downregulating the protein expression of ferritin, system xc (-) cystine/glutamate antiporter (xCT), and glutathione peroxidase 4 (GPX4), acting as the inhibitory factors of ferroptosis and increasing the intracellular levels of lipid reactive oxygen species (ROS). As a transcriptional regulator, KLF11 significantly increased the promoter activity of nuclear receptor coactivator 4 (NCOA4), a gene significantly downregulated in ccRCC and whose low expression is associated with poor survival. The characteristics of ccRCC cells caused by KLF11 overexpression were reversed after NCOA4 silencing. In summary, the present study suggests that KLF11 suppresses the progression of ccRCC by increasing NCOA4 transcription. Therefore, the KLF11/NCOA4 axis may serve as a novel therapeutic target for human ccRCC.

Adiponectin overexpression promotes fracture healing through regulating the osteogenesis and adipogenesis balance in osteoporotic mice.

INTRODUCTION: Osteoporosis invariably manifests as loss of bone, which is replaced by adipose tissue; this can easily lead to fractures, accompanied by delayed and poor healing. Adiponectin (APN) balances osteogenesis and adipogenesis in bone marrow mesenchymal stem cells (BMSCs). Therefore, this study explored whether adiponectin promotes bone fracture healing by regulating the balance between osteogenesis and adipogenesis. MATERIALS AND METHODS: We used adenovirus overexpression vectors carrying APN (Ad-APN-GFP) to treat ovariectomized (OVX) mouse BMSCs and osteoporotic bone fractures to investigate the role of APN in bone microenvironment metabolism in osteoporotic fractures. We subsequently established an OVX mice and bone fracture model using Ad-APN-GFP treatment to investigate whether APN could promote bone fracture healing in osteoporotic mice. RESULTS: The experimental results showed that APN is a critical molecule in diverse differentiation directions in OVX mouse BMSCs, with pro-osteogenesis and anti-adipogenesis properties. Importantly, our study revealed that Ad-APN-GFP treatment facilitates bone generation and healing around the osteoporotic fracture ends. Moreover, we identified that Sirt1 and Wnt signaling were closely related to the pro-osteogenesis and anti-adipogenesis commitment of APN in OVX mouse BMSCs and femoral tissues. CONCLUSION: We demonstrated that APN overexpression facilitates bone fracture healing in osteoporosis. Furthermore, APN overexpression promoted bone formation in OVX mouse BMSCs and bone fracture ends by regulating the balance between osteogenesis and adipogenesis both in vitro and in vivo.

Combined therapy of prednisone and mTOR inhibitor sirolimus for treating retroperitoneal fibrosis.

OBJECTIVES: Retroperitoneal fibrosis (RPF) is a rare autoimmune disease with fibrous tissue growth and inflammation in retroperitoneum. Its current treatments involve long-term uptake of glucocorticoids (e.g., prednisone) for controlling inflammation; however, side effects are common. We strived for an improved therapy for fibrosis remission while reducing side effects. METHODS: We surveyed gene-disease-drug databases and discovered that mammalian target of rapamycin (mTOR) was a key signalling protein in RPF and the mTOR inhibitor compound sirolimus affected many RPF pathways. We designed a therapy combining a gradual reduction of prednisone with a long-term, stable dosage of sirolimus. We then implemented a single-arm clinical trial and assessed the effects in eight RPF patients at 0, 12 and 48 weeks of treatment by measuring fibrous tissue mass by CT, markers of inflammation and kidney functions by lab tests, immune cell profiles by flow cytometry and plasma inflammatory proteins by Olink proteomics. RESULTS: With the combined therapy, fibrous tissue shrunk about by half, markers of acute inflammation reduced by 70% and most patients with abnormal kidney functions had them restored to normal range. Molecularly, fibrosis-related T cell subsets, including TH2, TH17 and circulating TFH cells, were reduced and tumour necrosis factor and related cytokines restored to healthy levels. No severe long-term side effects were observed. CONCLUSIONS: Our combined therapy resulted in significant fibrosis remission and an overall regression of the immune system towards healthy states, while achieving good tolerance. We concluded that this new therapy had the potential to replace the steroid monotherapy for treating RPF.

A Systematic Review and Meta-Analysis of Complications among Various Reduction Malarplasty.

BACKGROUND: Reduction malarplasty is one of the most common aesthetic procedures to improve a wide bizygomatic width and a prominent zygomatic body. Although there are various kinds of modifications, any method is imperfect, while some complications may occur. The purpose of this review was to compare kinds of complications of reduction malarplasty to provide certain suggestions for clinical application. METHODS: A comprehensive computerized search of scientific literature was performed via the PubMed, Web of Science, and Library of Congress databases, involved in articles from January 1st, 1983 to February 28th, 2022. The outcomes were extracted and analyzed by 3 independent authors, including patient demographics, diagnoses, surgical techniques, postoperative outcomes, and complications. RESULTS: A total of 29 studies covering 6611 patients were included according to the inclusion and exclusion criteria. The L-shaped osteotomy may obtain a better effect when someone has both zygomatic body and arch protrusion. In the view of complications, our conclusion suggested that L-shaped osteotomy without bony resection reduced the zygomatic complex effectively with the lowest incidence of postoperative complications (0.02%). But the amount of bone resection is limited. If increasing bone resection is necessary, L-shaped osteotomy with long arm bony resection and L-shaped osteotomy with short arm bony resection are both preferable choices with lowest incidence of structural and functional complications, respectively. CONCLUSION: L-shaped osteotomy may obtain a better effect when a patient has both zygomatic body and arch protrusion. L-shaped osteotomy without bony resection reduced the zygomatic complex effectively with the lowest incidence of postoperative complications. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Efficacy of arthroscopic internal fixation with countersunk screw in the treatment of talus fracture.

Objective: To explore clinical effects of arthroscopic internal fixation with countersunk screw in the treatment of talus fracture. Methods: Forty-eight patients with talus fracture treated in hospital of Chengde Medical University from February 2015 to December 2019 were enrolled for present investigation. The patients with talus fracture were randomly assigned into two groups, with twenty-four patients per group. The patients with talus fracture in the observation group were treated with arthroscopic internal fixation with countersunk screw, while the traditional open reduction and internal fixation were applied for the ones in control group. The clinical efficacy of the patients was evaluated three months after the operation, and the preoperative and postoperative ankle joint functions, fracture-healing time, hospital stay, and complications were carefully compared between observation and control group. Results: A total efficiency as high as 91.67% was showed in observation group, which is distinctly better than the effective rate of control group (66.67%, P<0.05). Before operation, ankle function scores (AOFAS) of control group and observation group is 42.08 ± 4.29 and 41.75±5.31 with no significantly difference (P>0.05); while after the surgery, AOFAS scores of control group is significantly lower than that of observation group: (66.28±7.51 vs. 53.0 ±6.79, P<0.05). Moreover, healing time and hospitalized duration of observation group are 3.19±1.04 months and 3.57±0.97 days, which are also significantly shorter than 4.18±1.25 months and 8.28±2.54 days in control group, respectively, (P < 0.05). And the total complication rate in control group is 20.83%, which is higher than 8.33% in observation group (P >0.05). Conclusion: Arthroscopic internal fixation with countersunk screw can significantly improve the efficacy and ankle joint functions, shorten the fracture-healing time and hospital stays without increasing the incidence of complications.

Coaxial TP/APR electrospun nanofibers for programmed controlling inflammation and promoting bone regeneration in periodontitis-related alveolar bone defect models.

Periodontitis is a pathological dental condition that damages the periodontal tissue and leads to tooth loss. Bone regeneration in periodontitis-related alveolar bone defects remains a challenge for periodontists and tissue engineers because of the complex periodontal microenvironment. The inflammatory microenvironment is associated with poor osteogenesis; therefore, the reduction of inflammation is essential for bone regeneration in periodontitis-related alveolar bone defects. Here, we developed a programmed core-shell nanofibers that allows the sequential and controlled release of tea polyphenols (TP) and AdipoRon (APR) to control inflammation and promote bone regeneration to repair periodontitis-related alveolar bone defects. Core-shell nanofibers with a sequentially controlled release function were synthesized using electrospinning. We investigated the therapeutic effects of the nanofibers in vitro and in a mouse periodontitis model. The results of the release profiles demonstrated that TP was released rapidly in the early stages and APR was continuously released thereafter. In vitro experiments showed that the programmed core-shell nanofibers reduced the levels of proinflammatory cytokines and increased osteogenic differentiation in an inflammatory microenvironment. In vivo experiments, the programmed core-shell nanofibers ameliorated periodontal tissue inflammation and improved alveolar bone regeneration. Our results indicated that the programmed core-shell nanofibers with a sequential-release function provides an ideal strategy for repairing periodontitis-related alveolar bone defects, and its application in the treatment of diseases with spatiotemporal specificity is promising.

[Clinical therapeutic strategies of refracture after bone transport for tibial bone defect].

OBJECTIVE: To explore the clinical therapeutic strategies of refracture after Ilizarov bone transport technique in the treatment of tibial bone defect. METHODS: A retrospective study was performed on 19 patients with infected tibial bone defect treated by Ilizarov bone transport technique and then refracture from August 2010 to January 2020, including 18 males and 1 female with an average age of (37.7±13.0) years old ranging from 15 to 66 years old. Cause of injury invlved falling injury in 4 cases, crashing injury 1 case, crushing injury in 1 case and without obvious injury history in 13 cases. The ipsilateral distal femoral fracture in 2 cases occurred before the external fixator of tibia was removed, and the other 17 cases had a minimum of 1 day and a maximum of 30 months after the external fixator had been removed. The site of refracture was at regenerative zone in 8 cases, at docking site in 9 cases, at ipsilateral femoral shaft in 2 cases. According to the modified Simpson classification proposed by the author, the refracture was classified. The treatment of refracture include plaster splint, traction or external fixation. Bone healing and function were evaluated according to the standards of the Association for the Study and Application of the Method of Ilizarov(ASAMI). RESULTS: All patients were followed up, and the duration ranged from 9 to 17 months with an average of (12.3±3.2) months. According to the modified Simpson classification, there were 3 cases of type Ⅰa, 1 case of type Ⅰb, 3 cases of type Ⅰc, 1 case of type Ⅱ, 9 cases of type Ⅲ and 2 cases of type Ⅴ. All the refractures healed without infection or malunion. The fracture healing time of conservative treatment for 6 cases were 3, 5, 3, 2, 2, 2 months fespectively;and the healing time of fracture treated by surgery for 13 cases was 2 to 6 months, with an average of(4.4±1.4) months. According to ASAMI evaluation criteria, bony results showed all patients obtained excellent results, and functional results showed 6 patients got excellent results, 13 good beacause of ankle or knee stiffness. CONCLUSION: The modified Simpson classification could contain most clinical types of refracture after bone transport, and the external fixation is a simple and effective method for refracture.

Analysis of benign retroperitoneal schwannomas: a single-center experience.

Background： Retroperitoneal schwannomas are rare. The purpose of this study was to present our experience with the diagnosis and treatment of 67 such tumors. Methods： Retrospective analysis of 67 patients with retroperitoneal schwannoma admitted to Peking University International Hospital from 2015 to 2021. Results： 67 patients presented with retroperitoneal schwannomas, 37 cases had no obvious clinical symptoms. 62 cases were completely excised, 5 cases were subtotal resection, 7 cases were combined with organ resection. The intraoperative blood loss was 300ml (20-9000ml), the tumor maximum size was 9cm (2.5-26cm), post-complication occurred in 6 cases (9.0%). Compared with abdominal retroperitoneal tumors, pelvic retroperitoneal tumors had larger tumor volume, more bleeding, higher proportion of block resection, and longer postoperative hospitalization time (P<0.05). The residual mass progressed slowly in 5 patients with subtotal resection, and no obvious malignant transformation occurred. Conclusion：Complete resection of schwannoma can achieve a good long-term prognosis. Patients with residual tumor after surgery progress slowly and rarely become malignant. We recommend early resection after the discovery of a pelvic retroperitoneal schwannoma. Keywords： Schwannoma; Retroperitoneal neoplasms; Postoperative complications.

Epithelioid Inflammatory Myofibroblastic Sarcoma with Leukemoid Reaction.

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and aggressive inflammatory myofibroblastic tumour (IMT) variant. This report identifies the first case of EIMS with leukemoid reaction. This is also the first case in which pancreatic infiltration occurred from the disease onset. A 14-year male patient presented with an 18×18×10 cm mass at the retroperitoneal space and a white blood cell (WBC) count of 85×109/L. The mass and the invaded tissues were surgically removed with tumour-free margins. Histopathology and bone marrow aspiration confirmed the diagnosis of EIMS with leukemoid reaction. The tumour recurred with hepatic and pulmonary metastasis one month after the surgery. WBC count also increased progressively with the tumour recurrence. There is no consensus on the treatment of EIMS. Since ALK rearrangement presents in all the EIMS cases, surgical resection combined with crizotinib or other targeted drugs may improve the prognosis. Key Words: Sarcoma, Soft tissue neoplasms, Leukemoid reaction, Crizotinib.

Antigen-Specific T Cell Detection via Photocatalytic Proximity Cell Labeling (PhoXCELL).

Quantitative detection and characterization of antigen-specific T cells are crucial to our understanding of immune responses as well as the development of new immunotherapies. Herein, we report a spatiotemporally resolved method for the detection and quantification of cell-cell interactions via Photocatalytic proXimity CELl Labeling (PhoXCELL). The biocompatible photosensitizer dibromofluorescein (DBF) was leveraged and optimized as a nongenetic alternative of enzymatic approaches for efficient generation of singlet oxygen upon photoirradiation (520 nm) on the cell surface, which allowed the subsequent labeling of nearby oxidized proteins with primary aliphatic amine-based probes. We demonstrated that DBF-functionalized dendritic cells (DCs) could spatiotemporally label interacting T cells in immune synapses via rapid photoirradiation with quantitatively discriminated interaction strength, which revealed distinct gene signatures for T cells that strongly interact with antigen-pulsed DCs. Furthermore, we employed PhoXCELL to simultaneously detect tumor antigen-specific CD8+ as well as CD4+ T cells from tumor-infiltrating lymphocytes and draining lymph nodes in murine tumor models, enabling PhoXCELL as a powerful platform to identify antigen-specific T cells in T cell receptor (TCR)-relevant personal immunotherapy.

A dual role of HIF1α in regulating osteogenesis-angiogenesis coupling.

OBJECTIVES: The hypoxia-inducible factor 1-α (HIF1α), a key molecule in mediating bone-vessel crosstalk, has been considered a promising target for treating osteoporosis caused by gonadal hormones. However, senile osteoporosis, with accumulated senescent cells in aged bone, has a distinct pathogenesis. The study aimed at revealing the unknown role of HIF1α in aged bone, thus broadening its practical application in senile osteoporosis. MATERIALS AND METHODS: Femurs and tibias were collected from untreated mice of various ages (2 months old, 10 months old, 18 months old) and treated mice (2 months old, 18 months old) underwent 4-w gavage of 2-methoxyestradiol (a kind of HIF1α inhibitor). Bone-vessel phenotypes were observed by microfil infusion, micro-CT and HE staining. Markers of senescence, osteogenesis, angiogenesis, oxidative stress and expression of HIF1α were detected by senescence ß-galactosidase staining, qRT-PCR, western blot and immunostaining, respectively. Furthermore, bone mesenchymal stem cells from young mice (YBMSCs) and aged mice (ABMSCs) were transfected by knockout siRNA and overexpression plasmid of HIF1α. Senescence ß-galactosidase staining, Cell Counting Kit-8, transwell assay, alkaline phosphatase staining, alizarin red-S staining and angiogenesis tests were utilized to assess the biological properties of two cell types. Then, Pifithrin-α and Nutlin-3a were adopted to intervene p53 of the two cells. Finally, H2O2 on YBMSCs and NAC on ABMSCs were exploited to change their status of oxidative stress to do a deeper detection. RESULTS: Senescent phenotypes, impaired osteogenesis-angiogenesis coupling and increased HIF1α were observed in aged bone and ABMSCs. However, 2-methoxyestradiol improved bone-vessel metabolism of aged mice while damaged that of young mice. Mechanically, HIF1α showed opposed effects in regulating the cell migration and osteogenesis-angiogenesis coupling of YBMSCs and ABMSCs, but no remarked effect on the proliferation of either cell type. Pifithrin-α upregulated the osteogenic and angiogenic markers of HIF1α-siRNA-transfected YBMSCs, and Nutlin-3a alleviated those of HIF1α-siRNA-transfected ABMSCs. The HIF1α-p53 relationship was negative in YBMSCs and NAC-treated ABMSCs, but positive in ABMSCs and H2O2-treated YBMSCs. CONCLUSION: The dual role of HIF1α in osteogenesis-angiogenesis coupling may depend on the ROS-mediated HIF1α-p53 relationship. New awareness about HIF1α will be conducive to its future application in senile osteoporosis.