Bone marrow mesenchymal stem cell-derived exosomal microRNAs target PI3K/Akt signaling pathway to promote the activation of fibroblasts.

BACKGROUND: Fibroblast plays a major role in tendon-bone healing. Exosomes derived from bone marrow mesenchymal stem cells (BMSCs) can activate fibroblasts and promote tendon-bone healing via the contained microRNAs (miRNAs). However, the underlying mechanism is not comprehensively understood. Herein, this study aimed to identify overlapped BMSC-derived exosomal miRNAs in three GSE datasets, and to verify their effects as well as mechanisms on fibroblasts. AIM: To identify overlapped BMSC-derived exosomal miRNAs in three GSE datasets and verify their effects as well as mechanisms on fibroblasts. METHODS: BMSC-derived exosomal miRNAs data (GSE71241, GSE153752, and GSE85341) were downloaded from the Gene Expression Omnibus (GEO) database. The candidate miRNAs were obtained by the intersection of three data sets. TargetScan was used to predict potential target genes for the candidate miRNAs. Functional and pathway analyses were conducted using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively, by processing data with the Metascape. Highly interconnected genes in the protein-protein interaction (PPI) network were analyzed using Cytoscape software. Bromodeoxyuridine, wound healing assay, collagen contraction assay and the expression of COL I and α-smooth muscle actin positive were applied to investigate the cell proliferation, migration and collagen synthesis. Quantitative real-time reverse transcription polymerase chain reaction was applied to determine the cell fibroblastic, tenogenic, and chondrogenic potential. RESULTS: Bioinformatics analyses found two BMSC-derived exosomal miRNAs, has-miR-144-3p and has-miR-23b-3p, were overlapped in three GSE datasets. PPI network analysis and functional enrichment analyses in the GO and KEGG databases indicated that both miRNAs regulated the PI3K/Akt signaling pathway by targeting phosphatase and tensin homolog (PTEN). In vitro experiments confirmed that miR-144-3p and miR-23b-3p stimulated proliferation, migration and collagen synthesis of NIH3T3 fibroblasts. Interfering with PTEN affected the phosphorylation of Akt and thus activated fibroblasts. Inhibition of PTEN also promoted the fibroblastic, tenogenic, and chondrogenic potential of NIH3T3 fibroblasts. CONCLUSION: BMSC-derived exosomes promote fibroblast activation possibly through the PTEN and PI3K/Akt signaling pathways, which may serve as potential targets to further promote tendon-bone healing.

Cellular immunotherapy combined with platinum-based chemotherapy prolongs survival for non-small cell lung cancer patients.

Platinum-based chemotherapy is the primary treatment option for advanced non-small cell lung cancer (NSCLC) patients without a driver gene mutation, but its efficacy is still modest. Through a potential synergistic effect, autologous cellular immunotherapy (CIT) composed of cytokine-induced killer (CIK), natural killer (NK), and T cells might enhance it. NK cells exhibited in vitro cytotoxicity toward lung cancer cells (A549 cells) following platinum therapy. Using flow cytometry, the expression of MICA, MICB, DR4, DR5, CD112, and CD155 on lung cancer cells was assessed. In this retrospective cohort study, there were included 102 previously untreated stage IIIB/IV NSCLC patients ineligible for tyrosine kinase inhibitor (TKI) target therapy who received either chemotherapy alone (n=75) or combination therapy (n=27). The cytotoxicity of NK cells for A549 cells was increased obviously and a time-dependent enhancement of this effect was also observed. After platinum therapy, the levels of MICA, MICB, DR4, DR5, CD112, and CD155 on the surface of A549 cells were increased. In the combination group, the median PFS was 8.3 months, compared to 5.5 months in the control group (p=0.042); the median overall survival was 18.00 months, compared to 13.67 months in the combined group (p=0.003). The combination group had no obvious immune-related adverse effects. The combination of NK cells with platinum showed synergistic anticancer effects. Combining the two strategies increased survival with minor adverse effects. Incorporating CIT into conventional chemotherapy regimens may improve NSCLC treatment. However, additional evidence will require multicenter randomized controlled trials.

Circulating tumor DNA-minimal residual disease: An up-and-coming nova in resectable non-small-cell lung cancer.

Circulating tumor DNA (ctDNA) in the bloodstream can be used to reliably identify a minimal residual disease (MRD). ctDNA-MRD has demonstrated clinical values as a predictive and prognostic marker for resectable non-small cell lung cancer (NSCLC) regarding efficacy evaluation, recurrence monitoring, risk classification, and adjuvant treatment choices, and it has the advantage of being non-invasive, real-time, and dynamic. A recent large-scale prospective study of patients with resectable NSCLC revealed that patients with longitudinal undetectable MRD might represent a potentially curable population, benefiting many patients by eliminating wasteful therapies and side effects. However, there are still barriers to using ctDNA-MRD in clinical management, and the most significant is the lack of high-sensitivity detection technologies and consistent detection times. Herein, we defined the clinical significance of ctDNA-MRD in resectable NSCLC, summarized the available next-generation sequencing (NGS) detection approaches, and speculated on future clinical trial design and detection technology optimization.

H-loop Knotless Double-Row Repair Versus Knotted Suture Bridge for Rotator Cuff Tears: A Biomechanical and Histological Study in an Animal Model [Formula: see text].

BACKGROUND: Knotted suture bridge repair (KSBR) has been widely proven to be an effective method for rotator cuff repairs. However, the occurrence of type 2 failure after suture bridge repair remains a frequent problem because of the stress concentration and disturbance of tendon perfusion in the medial row. The authors have developed the H-loop knotless double-row repair (HLDR) to counteract these problems. PURPOSE: To compare the biomechanical and histological outcomes of HLDR and KSBR for rotator cuff tear in the rabbit model. STUDY DESIGN: Controlled laboratory study. METHODS: Acute bilateral supraspinatus tears were created on the shoulders of 46 New Zealand White rabbits. HLDR and KSBR were randomly performed on the left side or right side. Thirteen animals each were sacrificed at 2, 4, and 8 weeks after surgery (n = 39), with 6 rabbits used for histological evaluation and the other 7 rabbits for biomechanical testing. The remaining 7 animals from the original 46 were only used for initial biomechanical evaluation at week 0. RESULTS: Macroscopically, all repaired tendons were connected to their footprint on the greater tuberosity without postoperative complications at 8 weeks after surgery. The HLDR group had significantly better histological bone-to-tendon integration compared with the KSBR group in terms of fibrocartilage regeneration, collagen composition, and fiber organization. The biomechanical outcomes in the HLDR group were demonstrated to be better than those of the KSBR group at time 0 and 8 weeks after surgery. CONCLUSION: Both repair techniques were effective for rotator cuff tears in a rabbit rotator cuff tear model; however, HLDR demonstrated more advantages in improving biomechanical properties and histological tendon-to-bone healing compared with KSBR. CLINICAL RELEVANCE: This animal study suggested that HLDR might be an alternative choice for rotator cuff tears in humans to increase tendon-to-bone healing and reduce the rate of failure to heal.

Arthroscopic Superior Capsule Reconstruction and Rotator Cuff Repair to Restore Static and Dynamic Stability of the Shoulder.

OBJECTIVE: Treatment of massive irreparable rotator cuff tears (RCT) has shown limited clinical success and a variety of subsequent complications. Superior capsule reconstruction (SCR) has been proved to reestablish superior stability but does not restore the dynamic force or shoulder kinematics. There are numerous reports of the short-term failure of SCR grafts at the glenoid side, which relate to the non-biological healing of grafts. To restore both dynamic and static stability and to provide biologic augmentation, an integrated procedure for massive irreparable RCT using an Achilles tendon-bone allograft (ATBA) was developed. METHOD: This was a retrospect study completed between October 2019 and April 2020. A 71-year-old woman with massive and irreparable rotator cuff tears was enrolled in our study. The ATBA was folded into a double-layer structure. The superior layer (proximal portion) served as a bridge patch to dynamic the glenohumeral joint, while the inferior layer (distal portion) served as the superior capsule to restore static stability of glenohumeral joint. To enhance biologic healing on the glenoid side, we fixed the calcaneus of the graft on the superior-posterior side of the superior glenoid rim. The recovery of shoulder function (including strength, range of motion, acromiohumeral interval, and fatty infiltration) was assessed at 6 months postoperation. RESULT: At 6-month follow-up, the patient's strength had improved significantly (from abduction of grade 3 preoperatively to grade 4 at 6 months). Radiographic analysis showed an increase in the acromiohumeral interval from 3 to 7 mm. Magnetic resonance imaging revealed an intact graft, with the thickness of the ligament part maintained (at 6-7 mm). Most importantly, recovery of atrophy and fatty infiltration of the supraspinatus were observed. No graft tears were observed on the glenoid side. CONCLUSION: This technique could provide a preferable treatment option by restoring shoulder kinematics and augmentating biological healing for patients with massive irreparable RCT.