SPARC induces M2 polarization of macrophages to promote proliferation, migration, and angiogenesis of cholangiocarcinoma cells.

Cholangiocarcinoma (CCA) is a disease that includes a variety of epithelial neoplasms characterized by the differentiation of cholangiocytes. M2 polarization is imperative to the development of CCA cells. In this study, we investigated the influence of secreted protein acidic and rich in cysteine (SPARC) on M2 polarization and CCA cell growth. We found that the SPARC level was amplified in M2-polarized macrophages and TAMs. In addition, the downregulation of SPARC prevented the M2 polarization of macrophages. Silencing SPARC inhibited the M2 macrophage-mediated effects on the proliferation, migration, and angiogenesis of CCA cells. Additionally, SPARC knockdown blocked the M2 polarization of macrophages by inhibiting the PI3K/AKT signaling. Moreover, an activator of PI3K signaling repressed the effect of SPARC knockdown on the M2 macrophage-induced elevation of proliferation, migration, and angiogenesis in CCA cells. In conclusion, SPARC contributes to the M2 polarization of macrophages to promote proliferation, migration, and angiogenesis of CCA cells, which provides new insight into the treatment of CCA.

Activation of the PI3K-AKT signaling pathway by SPARC contributes to the malignant phenotype of cholangiocarcinoma cells.

Cholangiocarcinoma (CCA) is a primary biliary epithelium malignancy with limited therapies, poor prognosis and high mortality rate. Nowadays, the molecular mechanisms of CCA remain elusive. SPARC has been proposed to be highly expressed in clinical CCA tissues, but few studies has been elucidated its functions in CCA. In the current study, we aimed to investigate the functional role of SPARC in the progression of CCA. In this study, a significantly increased expression of SPARC was observed in CCA tissues and cells. Knockdown of SPARC by RNA interference significantly impeded the proliferation of CCA cells. Moreover, SPARC silencing hampered the migration and invasion of CCA cells by inhibiting EMT. In parallel, overexpression of SPARC in RBE cells had the opposite effects. Mechanically, SPARC promoted proliferation, migration, invasion, and EMT of CCA cells in vitro via activating the PI3K-AKT signaling. Overall, our integrated analysis revealed that SPARC plays a crucial role in CCA progression via the PI3K-AKT signaling pathway, which suggests that targeting SPARC might represent a promising approach for improving CCA patient's clinical outcome.

Modification and Characterization of Interfacial Bonding for Thermal Management of Ruthenium Interconnects in Next-Generation Very-Large-Scale Integration Circuits.

Ruthenium may replace copper interconnects in next-generation very-large-scale integration (VLSI) circuits. However, interfacial bonding between Ru interconnect wires and surrounding dielectrics must be optimized to reduce thermal boundary resistance (TBR) for thermal management. In this study, various adhesion layers are employed to modify bonding at the Ru/SiO2 interface. The TBRs of film stacks are measured using the frequency-domain thermoreflectance technique. TiN and TaN with high nitrogen contents significantly reduce the TBR of the Ru/SiO2 interface compared to common Ti and Ta adhesion layers. The adhesion layer thickness, on the other hand, has only minor effect on TBR when the thickness is within 2-10 nm. Hard X-ray photoelectron spectroscopy of deeply buried layers and interfaces quantitatively reveals that the decrease in TBR is attributed to the enhanced bonding of interfaces adjacent to the TaN adhesion layer, probably due to the electron transfer between the atoms at two sides of the interface. Simulations by a three-dimensional electrothermal finite element method demonstrate that decreasing the TBR leads to a significantly smaller temperature increase in the Ru interconnects. Our findings highlight the importance of TBR in the thermal management of VLSI circuits and pave the way for Ru interconnects to replace the current Cu-based ones.

Expression of miR-214 in pancreatic cancer and its effect on the biological function of pancreatic cancer cells.

PURPOSE: To study the expression and biological function of microRNA 214 (miR-214) in pancreatic cancer. METHODS: 101 patients with pancreatic cancer who came from First People's Hospital of Yunnan Province from December 2013 to December 2016 were selected. 101 pancreatic cancer tissues and 101 adjacent tissues were resected and collected. The miR-214 expression was detected by qRT-PCR. Then the pancreatic cancer cell line AsPC-1 and SW1990 were transfected. MTT assay was used to detect cell viability and flow cytometry was used to detect apoptosis. Transwell chamber assay was used to detect the invasion and migration of cells in vitro. The protein expressions of ING4 in AsPC-1 and SW1990 cells were detected by Western blot. RESULTS: The relative expression of miR-214 in pancreatic cancer was significantly higher than that in adjacent tissues (p<0.05). There was a statistically significant difference between the expression level of miR-214 and T stage of pancreatic cancer (p<0.05). The relative expression of ING4 protein in SW1990 cells of miR-214 mimics group was significantly lower than that of miR-214 control mimics group (p<0.05), and that in AsPC-1 cells of the miR-214 inhibitors group was significantly higher than that in the miR-214 control inhibitors group (p<0.05). CONCLUSION: In conclusion, the expression of miR-214 is highly expressed in pancreatic cancer tissues, and the down-regulation of ING4 protein expression can inhibit the proliferation, invasion and migration of pancreatic cancer cells, promote their apoptosis, and can be used as a new molecular target for the diagnosis and treatment of pancreatic cancer.

LncRNA HOTAIR Promotes Cancer Stem-Like Cells Properties by Sponging miR-34a to Activate the JAK2/STAT3 Pathway in Pancreatic Ductal Adenocarcinoma.

INTRODUCTION: Pancreatic Ductal Adenocarcinoma (PDAC) stem cells (CSCs) play a vital role in the occurrence, development and recurrence of PDAC. Previous studies have shown that long non-coding RNAs (lncRNA) are closely associated with occurrence and development of malignant tumors. Among them, a LncRNA called homeobox transcription antisense RNA (HOTAIR) plays a key role in cancer progression in a variety of malignant tumors, including PDAC. Numerous studies have associated HOTAIR with poor prognosis of malignant tumor treatment, owing to its role in regulating downstream microRNAs (miRNAs). However, its underlying mechanism of action on CSCs-like properties of PDAC remain unclear. METHODS: We enriched CSCs of PDAC with a serum-free medium (SFM), and analyzed the expression levels of HOTAIR and miR-34a after enrichment. In addition, we evaluated the regulatory effects of HOTAIR and miR-34a on CSCs-like properties, invasion and migration of PDAC. Finally, we elucidated the role of HOTAIR in pancreatic tumor xenotransplantation. RESULTS: HOTAIR was upregulated in CSCs following PDAC enrichment of PDAC. Conversely, miR-34a was downregulated and appeared to be a direct target of HOTAIR. Moreover, knocking down HOTAIR or overexpressing miR-34a significantly inhibited CSCs-like properties, invasion and migration of PDAC cells. Furthermore, HOTAIR activated the JAK2/STAT3 pathway through miR-34a, thereby promoting CSCs-like properties, invasion and migration of PDAC cells. In vivo experiments indicated that knocking down HOTAIR could inhibit the tumorigenicity of CFPAC-1 cells. CONCLUSION: This is the first report of HOTAIR-mediated activation of the JAK2/STAT3 pathway via miR-34a inhibition. This activation promotes CSCs-like properties, invasion and migration of PDAC.

Activin B signaling may promote the conversion of normal fibroblasts to scar fibroblasts.

This study is to explore the molecular mechanism of benign bile duct hypertrophic scar formation.Differential proteins between the normal fibroblast (NFB) and scar fibroblast (SCFB) were screened by protein chip assay, and analyzed by pathway-enrichment analysis and function-enrichment analysis. The differential proteins were further tested by ELISA. SiRNA-Act B was transfected to SCFB to down-regulate the expression of Act B. NFB was incubated with rh-Act B. The cell apoptosis and cell cycle were determined by flow cytometry. The expression of Act B, Smad2/3, transforming growth factor-ß1 (TGF-ß1), endothelin-1 (ET-1), thrombospondin-1 (Tsp-1), and Oncostatin M (OSM) were detected by Western blot.A total of 37 differential proteins were identified in SCFBs by microarray (P < .05), including 27 up-regulated proteins and 10 down-regulated proteins (P < .05). Their function were associated with Activin signaling, synthesis and degradation of extracellular matrix, formation and activation of cytokine, inflammatory reaction, immunoreaction, tissue damage reaction, cell cycle, migration, apoptosis, and secretion, etc. ELISA results showed that the expression of Act B, TGF-ß1, ET-1 were higher in SCFBs, while the expression of Tsp-1 and OSM were lower in SCFBs (P < .05). After interfered by siRNA-Act B, the expression of Act B mRNA decreased (P < .05). The percentage of early apoptosis increased (P < .05). The expression of Act B, Smad2/3, TGF-ß1 were decreased and Tsp-1, OSM were increased (P < .05). After treatment with rh-Act B, the percentage of G0/G1 phase of NFBs was decreased and that of S phase was increased without significance (P > .05). The expression of Act B, Smad2/3, TGF-ß1 were increased (P < .05) and Tsp-1, OSM were decreased (P < .01).There are differentially expressed proteins between SCFBs and NFBs. Activin B signal plays an important role in the process of NFB transforming to SCFB, and TGF-ß1, Smad2/3, Tsp-1, and OSM are important participants.

Transplantation of Hematopoietic Stem Cells Promotes Functional Improvement Associated with NT-3-MEK-1 Activation in Spinal Cord-Transected Rats.

Transected spinal cord injury (SCT) is a devastating clinical disease that strongly affects a patient's daily life and remains a great challenge for clinicians. Stem-cell therapy has been proposed as a potential therapeutic modality for SCT. To investigate the effects of hematopoietic stem cells (HSCs) on the recovery of structure and function in SCT rats and to explore the mechanisms associated with recovery, 57 adult Sprague-Dawley rats were randomly divided into sham (n = 15), SCT (n = 24), and HSC transplantation groups (n = 15). HSCs (passage 3) labeled by Hoechst 33342, were transplanted intraspinally into the rostral, scar and caudal sites of the transected lesion at 14 days post-operation. Both in vitro and in vivo, HSCs exhibited a capacity for cell proliferation and differentiation. Following HSC transplantation, the animals' Basso, Beattie, and Bresnahan (BBB). locomotion scale scores increased significantly between weeks 4 and 24 post-SCT, which corresponded to an increased number of 5-hydroxytryptamine (5-HT) fibers and oligodendrocytes. The amount of astrogliosis indicated by immunohistochemical staining, was markedly decreased. Moreover, the decreased expression of neurotrophin- 3 (NT-3) and mitogen-activated protein kinase kinase-1 (MEK-1) after SCT was effectively restored by HSC transplantation. The data from the current study indicate that intraspinally administered HSCs in the chronic phase of SCT results in an improvement in neurological function. Further, the results indicate that intraspinally administered HSCs benefit the underlying mechanisms involved in the enhancement of 5-HT-positive fibers and oligogenesis, the suppression of excessive astrogliosis and the upregulation of NT3-regulated MEK-1 activation in the spinal cord. These crucial findings reveal not only the mechanism of cell therapy, but may also contribute to a novel therapeutic target for the treatment of spinal cord injury (SCI).

Brain-derived Neurotrophic Factor Promotes Growth of Neurons and Neural Stem Cells Possibly by Triggering the Phosphoinositide 3-Kinase/ AKT/Glycogen Synthase Kinase-3ß/ß-catenin Pathway.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) plays a crucial role in promoting survival and differentiation of neurons and neural stem cells (NSCs), but the downstream regulating mechanisms remain poorly understood. OBJECTIVE: We investigated whether BDNF exerts its effect by triggering the phosphoinositide 3-kinase (PI3K), protein kinase B, PKB (AKT), glycogen synthase kinase-3ß (GSK-3ß) and ß-catenin signaling pathway in cultured neurons and NSCs derived from the rat embryonic spinal cord. METHOD: Immunocytochemistry was used to detect neuronal and NSCs characteristics. RT-PCR was used to detect PI3K/AKT/GSK3ß/ß-catenin pathway expression. RESULTS: Neurons and NSCs were successfully separated and cultured from Sprague-Dawley rat embryonic spinal cord and were respectively labeled using immunocytochemistry. Neuron-specific nuclear protein, neuronal class III ß-tubulin, and neurofilament expression were detected in neurons; nestin, glial fibrillary acidic protein, microtubule-associated protein 2 and chondroitin sulfate glycosaminoglycan expression were detected in the NSCs. BDNF promoted significant neuronal growth (number, soma size, and average neurite length), as well as NSCs proliferation and differentiation, but BDNF antibody decreased neuronal growth and NSCs proliferation and differentiation. RT-PCR was used to detect changes in BDNF signal pathway components, showing that BDNF upregulated tropomyosin receptor kinase B, phosphoinositide 3-kinase (PI3K), AKT and ß-catenin, but downregulated GSK-3ß in the neurons and NSCs. BDNF antibody downregulated BDNF, tropomyosin receptor kinase B, PI3K, AKT, ß-catenin and cellular-myelocytomatosis viral oncogene, but upregulated GSK- 3ß, in the neurons and NSCs. CONCLUSION: Our findings suggested that BDNF contributed to neuronal growth and proliferation and differentiation of NSCs in vitro by stimulating PI3K/AKT/GSK3ß/ß-catenin pathways.