Analysis of intercellular communication in the osteosarcoma microenvironment based on single cell sequencing data.

Osteosarcoma (OS) is the most common primary bone cancer in children and young adults, patient survival rates have not improved in recent decades. To further understand the interrelationship between different cell types in the tumor microenvironment of osteosarcoma, we comprehensively analyzed single-cell sequencing data from six patients with untreated osteosarcoma. Nine major cell types were identified from a total of 46,046 cells based on unbiased clustering of gene expression profiles and canonical markers. Osteosarcoma from different patients display heterogeneity in cellular composition. Myeloid cells were the most commonly represented cell type, followed by osteoblastic and TILs. Copy number variation (CNV) results identified amplifications and deletions in malignant osteoblastic cells and fibroblasts. Trajectory analysis based on RNA velocity showed that osteoclasts in the OS microenvironment could be differentiated from myeloid cells. Furthermore, we explored the intercellular communications in OS microenvironment and identified multiple ligand-receptor pairs between myeloid cells, osteoblastic cells and their cells, including 21 ligand-receptor pair genes that significantly associated with survival outcomes. Importantly, we found chemotherapy may have an effect on cellular communication in the OS microenvironment by analyzing single-cell sequencing data from seven primary osteosarcoma patients who received chemotherapy. We believe these observations will improve our understanding of potential mechanisms of microenvironment contributions to OS progression and help identify potential targets for new treatment development in the future.

Clinical Application of a Modified Local Transposition Flap (Parallelogram Flap) Surgery in Repairing Fingertip Defects.

OBJECTIVE: Parallelogram flap was performed for transverse finger amputation with the loss of distal pulp, nails, and bone. This study aimed to compare the clinical effects of parallelogram flap, antegrade homodigital island flaps, and reverse digital artery island flaps in fingertip reconstruction. PATIENTS AND METHODS: From January 2017 to January 2021, clinical patient data with parallelogram flaps (78 cases), antegrade homodigital island flaps (78 cases), and reverse digital artery island flaps (78 cases) to repair fingertip defects were collected and analyzed. Two hundred thirty-four cases (234 fingers) were included in our study. All operations were performed by one surgical team. The operation time, 2-point discrimination, total active movement, and the Michigan Hand Questionnaire (MHQ) of the injured fingers were recorded to evaluate the therapeutic effect. RESULTS: Parallelogram flaps (group A), antegrade homodigital island flaps (group B), and reverse digital artery island flaps (group C) had survived postoperatively. The operative duration of group A is the shortest (A < B < C, P < 0.05). At the last 6-month follow-up, there was no difference with the 2-point discrimination of the palmar part of the flaps in group A and group B but better than group C (P < 0.05). There was no difference with the total active movement of injured figures in 3 groups (P > 0.05). The MHQ summary scores in group A were much higher than those in group B and group C (P < 0.05). Evaluation of the MHQ subscale performance showed that the overall hand function, activities of daily living, work performance, and pain score had no differences (P > 0.05), but aesthetics and satisfaction score was the highest in group A (A > B > C, P < 0.05). CONCLUSIONS: The reconstruction of transverse finger amputation using parallelogram flaps can achieve a shorter operation time, a more satisfying appearance. Parallelogram flaps and antegrade homodigital island flaps can both achieve a better sensory recovery. Parallelogram flaps is a better choice for reconstruction of transverse finger amputation with the loss of distal pulp, nails, and bone.

TUDCA protects against tunicamycin-induced apoptosis of dorsal root ganglion neurons by suppressing activation of ER stress.

The existence of endoplasmic reticulum (ER) stress in neurodegenerative diseases has been well established. Tauroursodeoxycholic acid (TUDCA) is a bile acid taurine conjugate derived from ursodeoxycholic acid, which has been reported to exert cytoprotective effects on several types of cells by inhibiting ER stress. The present study explored the effects of TUDCA on primary cultured rat dorsal root ganglion (DRG) neurons. Cell viability and apoptosis of DRG neurons treated with TUDCA and tunicamycin were detected by CellTiter-Blue assay and TUNEL staining, respectively. The protein levels and phosphorylation of apoptosis and ERS-related signaling pathway molecules were detected by western blot, and the mRNA levels of related genes were assessed by reverse transcription-quantitative PCR. Notably, TUDCA had no significant cytotoxic effect on DRG neurons at concentrations ≤250 µM. In addition, the apoptosis induced by tunicamycin exposure was markedly suppressed by TUDCA, as indicated by the percentage of TUNEL-positive cells, the activities of caspases and the changes in expression levels of critical apoptosis factors. Furthermore, the cytotoxicity of tunicamycin in DRG neurons was accompanied by an increase in malondialdehyde (MDA) content, reactive oxygen species (ROS) and lactate dehydrogenase (LDH) production, and a decrease in glutathione (GSH) levels. The changes in oxidative stress-related factors (ROS, LDH, MDA and GSH) were reversed by TUDCA. Furthermore, as determined by western blotting, the increase in C/EBP homologous protein, glucose-regulated protein 78 and cleaved caspase-12 expression following tunicamycin treatment suggested the activation of ER stress. Downregulation of ER stress components and unfolded protein response sensors by TUDCA confirmed the implication of ER stress in the effects of TUDCA on DRG neurons. In conclusion, the present study indicated that TUDCA may protect against tunicamycin-induced DRG apoptosis by suppressing the activation of ER stress. The protective effect and the therapeutic value of TUDCA in nervous system injury require further study in animal models.

Parallelogram flap versus homodigital island flap in the treatment of fingertip defects with bone exposure: a prospective controlled study.

PURPOSE: A modified local transposition flap (we call it "parallelogram flap") surgery was performed for fingertip injuries. This study aimed to compare the clinical effects of parallelogram flap and homodigital island flaps in fingertip reconstruction. METHODS: The study collected patients who underwent parallelogram transposition flaps and homodigital island flaps to repair fingertip defects from 2019 to 2021. 150 cases (150 fingers) were included in our study. All operations were performed by one surgical team. Record the operation time, two-point discrimination (2PD), Total Active Movement (TAM) and the MHQ (Michigan Hand Questionnaire) of the injured fingers to evaluate the therapeutic effect. RESULTS: All parallelogram (Group A) and homodigital island flap (Group B) had survived postoperatively. The operative duration of Group A (31.2 ± 3.3 min) is shorter than Group B (97.8 ± 6.1 min) (P < 0.05). At the 6-month follow-up, there was no difference with the two-point discrimination (2PD) of the palmar part of the flaps and the Total Active Movement (TAM) of injured figures in Group A and Group B. The MHQ summary scores in Group A (94.29 ± 3.14) were much higher than in Group B (91.73 ± 3.41) (P < 0.05). Evaluation of the MHQ subscale performance showed that the overall hand function, activities of daily living, work performance and pain score had no differences(P > 0.05), but aesthetics (92.15 ± 7.16) and satisfaction (92.45 ± 5.61) score in Group A was higher than aesthetics (86.56 ± 5.60) and satisfaction (86.72 ± 8.21) score in Group B (P < 0.05 for both). CONCLUSIONS: The reconstruction using parallelogram flaps is a easier and more versatile treatment with better functions, less morbidity and better aesthetics. This method is a better choice for reconstruction of fingertip injury.

A LncRNA-miRNA-mRNA ceRNA regulatory network based tuberculosis prediction model.

The high incidence of tuberculosis (TB) has brought serious social burdens and it is urgent to explore the mechanism of TB development. This study was conducted to analyze the role of lncRNA-miRNA-mRNA regulatory network and its contained nodes involved in TB to identify crucial biomarkers for early diagnosis of TB. Long-noncoding RNAs (lncRNAs), messenger RNA (mRNAs) and microRNAs (miRNAs) expression profiles of TB patients and healthy individuals were downloaded from the GSE34608 dataset. Weighted gene co-expression network analysis (WGCNA) was performed to identified the key modules related to TB and the highly related mRNA-lncRNA pair in the module. Based on highly related mRNAs and lncRNAs in greenyellow module, lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) network was constructed. The DE-mRNAs in the network were functionally enriched with Gene ontology (GO) and Gene set enrichment analysis (GSEA). Least absolute shrinkage and selection operator (LASSO) algorithm and receiver operating characteristic curve (ROC) were used to construct and evaluate the prediction model of TB. We identified 3267 DE-mRNAs, 484 DE-lncRNAs and 69 DE-miRNAs between the TB and healthy subjects, from which 8 DE-mRNAs, 14 DE-lncRNAs and 3 DE-miRNAs were used to construct the ceRNA network. The genes contained in the ceRNA network were mainly enriched in neutrophil mediated immune response, including neutrophil activation, degradation and signal transduction. ROC analysis revealed that has-miR-140-5p, has-miR-142-3p and the LASSO cox prediction model based on HMGA1 and CAPN1 have potential value for forecasting TB (AUC > 0.7). Hence, our study provides a new perspective from the lncRNA-miRNA-mRNA ceRNA regulatory network for TB diagnosis and treatment.

LncRNA HOTTIP leads to osteoarthritis progression via regulating miR-663a/ Fyn-related kinase axis.

BACKGROUND: Long non-coding RNA (lncRNA) has been implicated in the progression of osteoarthritis (OA). This study was aimed to explore the role and molecular mechanism of lncRNA HOXA terminal transcriptional RNA (HOTTIP) in the development of OA. METHODS: The expression of HOTTIP, miR-663a and Fyn-related kinase (FRK) in the OA articular cartilage and OA chondrocyte model induced by IL-1ß was determined by qRT-PCR. CCK-8, colony formation and flow cytometry were used to determine the cell proliferation and apoptosis of OA chondrocytes. The specific molecular mechanism of HOTTIP in OA chondrocytes was determined by dual luciferase reporter assay, qRT-PCR, western blotting and RNA pull-down. RESULTS: The expression of HOTTIP and FRK were up-regulated, while miR-663a was down-regulated in OA cartilage tissues. Knockdown of HOTTIP decreased the proliferation and induced the apoptosis of OA cartilage model cells, while overexpression of HOTTIP increased the proliferation and reduced the apoptosis of OA cartilage model cells. Moreover, HOTTIP could bind to miR-663a as competitive endogenous RNA. Inhibition of miR-663a expression could alleviate the effect of HOTTIP knockdown on the proliferation and apoptosis of OA cartilage model cells. Furthermore, FRK was found to be a direct target of miR-663a, which could markedly down-regulate the expression of FRK in OA chondrocytes, while HOTTIP could remarkably up-regulate the expression of FRK. In addition, miR-663a inhibition increased the proliferation and reduced the apoptosis of OA cells, while FRK knockdown reversed the effect of miR-663a inhibition on the proliferation and apoptosis of OA cells. Meanwhile, overexpression of miR-663a decreased the proliferation and induced the apoptosis of OA cells, while overexpression of FRK reversed the effect of miR-663a overexpression on the proliferation and apoptosis of OA cells. CONCLUSION: HOTTIP was involved in the proliferation and apoptosis of OA chondrocytes via miR-663a/ FRK axis, and HOTTIP/miR-663a/FRK might be a potential target for the treatment of OA.