Dalian Medical University

About: Dalian Medical University is a education organization based out in Dalian, China. It is known for research contribution in the topics: Cancer & Apoptosis. The organization has 15623 authors who have published 9993 publications receiving 164145 citations.

Abnormally elevated USP37 expression in breast cancer stem cells regulates stemness, epithelial-mesenchymal transition and cisplatin sensitivity.

Abstract: Recent studies have indicated that deubiquitinating enzymes (DUBs) are related to the stem-cell pathway network and chemo-resistance in cancer. Ubiquitin-specific peptidase 37 (USP37), a novel DUB, was identified to be a potential factor associated with tumor progression. However, the biological functions of USP37 in breast cancer remain unclear. The distribution of USP37 expression in breast cancer and the correlation between USP37 expression and the overall survival rate were detected by The Cancer Genome Atlas (TCGA) database. Gene set enrichment analysis (GSEA) was utilized to evaluate potential mechanism of USP37 in breast cancer. The USP37 expression in breast cancer tissues and breast cancer cell lines were detected by immunohistochemistry and western blotting. Sorting of breast cancer stem cells (BCSCs) were by using MACS assay. In vitro and in vivo assays were performed to examine the biological functions of USP37 in breast cancer cells. MG132, CHX chase, immunofluorescence staining and co-immunoprecipitation assays were used to test the interaction between USP37 and Gli-1. Bioinformatics analysis demonstrated that USP37 gene was elevated in breast cancer tissues and its overexpression was strongly correlated with the increased mortality rate. GSEA analysis showed that USP37 expression was positively associated with cell growth and metastasis while negatively related to cell apoptosis in the TCGA breast cancer samples. USP37 expression was elevated in breast cancer tissues and breast cancer cell lines. Moreover, we also detected that USP37 was overexpressed in BCSCs. USP37 regulated the ability of cell invasion, epithelial-mesenchymal transition (EMT), stemness and cisplatin sensitivity in breast cancer cell lines. Additionally, USP37 knockdown inhibited tumorigenicity and increased anticancer effect of cisplatin in vivo. Knockdown of USP37 significantly decreased hedgehog (Hh) pathway components Smo and Gli-1. Gli-1 was stabilized by USP37 and they interacted with each other. Further studies indicated that USP37 knockdown could inhibit the stemness, cell invasion and EMT in breast cancer via downregulation of Hh pathway. These findings reveal that USP37 is highly expressed in BCSCs and is correlated with poor prognosis in breast cancer patients. USP37 can regulate the stemness, cell invasion and EMT via Hh pathway, and decreased USP37 confers sensitivity to cisplatin in breast cancer cells. USP37 is required for the regulation of breast cancer progression, as well as a critical target for clinical treatment of breast cancer.

Overexpression of Hedgehog signaling molecules and its involvement in triple-negative breast cancer

Abstract: The purpose of this study was to investigate the activation of Hedgehog (Hh) signaling molecules and its involvement in triple-negative breast cancer (TNBC). A total of 123 cases of paraffin blocks, including 83 cases of primary breast carcinoma, 30 cases of mammary hyperplasia and 10 cases of normal breast tissue, were immunohistochemically analyzed for Sonic Hedgehog (SHH), Patched-1 (PTCH1), Smoothened (SMO) and glioma-associated oncogene homoglog 1 (GLI1) expression. The expression of SMO and GLI1 in TNBC was significantly increased in comparison to non-triple-negative breast cancer (nTNBC). GLI1 expression manifested an inverse association with the estrogen receptor. The levels of GLI1 expression were increased in lymph node-positive cases. The expression of SHH and SMO was increased in high histological grades. Furthermore, the expression of SMO and GLI1 was correlated with superior tumor stage. The expression of SHH, SMO and GLI1 was significantly increased in breast cancer and mammary hyperplasia. PTCH1 expression was significantly decreased in breast cancer compared to mammary hyperplasia and normal breast tissue. For the first time, clinical evidence has been provided in support of significant roles of Hh signaling in TNBC. Hh signaling is involved in breast ductal changes and malignant transformation. Measures to inhibit Hh activity may improve the prognosis of TNBC patients.

Noise induced reversible changes of cochlear ribbon synapses contribute to temporary hearing loss in mice

Abstract: Conclusion: Noise exposure can cause a decline in cochlear ribbon synapses and result in consequent hearing loss. The reduction of synaptic puncta appears reversible and may contribute to hearing restoration in mice after noise exposure. Objective: To detect whether noise induced reversible changes of cochlear ribbon synapses contribute to temporary hearing loss in C57BL/6J mice. Methods: The mice were assigned randomly to five groups and exposed to white noise at 110 dB SPL for 2 h except the control group. ABR thresholds were acquired before noise exposure (control), immediately following exposure (Day 0), or on Days 4, 7, or 14 after noise exposure. Light microscopy, scanning emission microscopy, and whole mounts examination was utilized to study whether there is morphology change of outer hair cells (OHC), inner hair cells (IHC), or spiral ganglion cells (SGN) due to the 110 dB white noise. Moreover, experimental approaches, including immunostaining and confocal microcopy, were used to detect ...