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.

STEAP3 promotes cancer cell proliferation by facilitating nuclear trafficking of EGFR to enhance RAC1-ERK-STAT3 signaling in hepatocellular carcinoma.

STEAP3 (Six-transmembrane epithelial antigen of the prostate 3, TSAP6, dudulin-2) has been reported to be involved in tumor progression in human malignancies. Nevertheless, how it participates in the progression of human cancers, especially HCC, is still unknown. In the present study, we found that STEAP3 was aberrantly overexpressed in the nuclei of HCC cells. In a large cohort of clinical HCC tissues, high expression level of nuclear STEAP3 was positively associated with tumor differentiation and poor prognosis (p < 0.001), and it was an independent prognostic factor for HCC patients. In HCC cell lines, nuclear expression of STEAP3 significantly promoted HCC cells proliferation by promoting stemness phenotype and cell cycle progression via RAC1-ERK-STAT3 and RAC1-JNK-STAT6 signaling axes. Through upregulating the expression and nuclear trafficking of EGFR, STEAP3 participated in regulating EGFR-mediated STAT3 transactivity in a manner of positive feedback. In summary, our findings support that nuclear expression of STEAP3 plays a critical oncogenic role in the progression of HCC via modulation on EGFR and intracellular signaling, and it could be a candidate for prognostic marker and therapeutic target in HCC.