Proteomic analysis identifies translationally controlled tumor protein as a mediator of phosphatase of regenerating liver-3-promoted proliferation, migration and invasion in human colon cancer cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Considerable evidence suggests that phosphatase of regenerating liver-3 (PRL-3) plays multiple roles in cancer metastasis; however, the molecular mechanisms remain largely unknown. The aim of this study was to identify proteins associated with PRL-3-promoted colon cancer metastasis, by comparative proteomic analysis.</p><p><b>METHODS</b>Proteomes of human colon cancer LoVo cells transfected with PRL-3 gene (LoVo-PRL-3) or empty vector PAcGFP-C3 (LoVo-control) were compared using 2D gel electrophoresis. Proteins that varied significantly in concentration were selected and identified using mass spectrometry. Expression of translationally controlled tumor protein (TCTP) mRNA and protein in LoVo-PRL-3 and LoVo-control cells was detected by real-time PCR and Western blotting. Small interfering RNA (siRNA) targeting TCTP was used for silencing TCTP expression in LoVo-PRL-3 cells. Functional significance of TCTP in PRL-3-promoted colon cancer cell proliferation, migration and invasion was investigated by Cell Counting Kit-8 assay and transwell chamber.</p><p><b>RESULTS</b>Seventeen proteins displaying significant and reproducible differences between LoVo-PRL-3 and LoVo-control cells were identified. Ten proteins were upregulated and seven were downregulated in LoVo-PRL-3 cells when compared with LoVo-control cells. Eight identified proteins are associated with distinct steps of tumor metastasis: ubiquitin-like protein ISG15, interleukin-18, TCTP, serpin B5, annexin A3, macrophage-capping protein, ATP-dependent RNA helicase DDX3X, and cathepsin D. Real-time PCR and Western blotting results showed that both TCTP mRNA and protein were significantly increased in LoVo-PRL-3 cells compared to LoVo-control cells. Transfection with TCTP siRNA significantly reduced the expression of both mRNA and protein levels of TCTP in LoVo-PRL-3 cells. Knockdown of TCTP by siRNA inhibited PRL-3-promoted proliferation, migration and invasion of LoVo-PRL-3 cells.</p><p><b>CONCLUSION</b>Our results imply that TCTP might be a mediator of PRL-3-promoted proliferation, migration and invasion of human colon cancer cells.</p>

Expression of heat shock protein 27 in the esophageal tissue of rats with reflux esophagitis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Little attention has been paid to the expression of heat shock protein 27 (HSP27) in patients with reflux esophagitis (RE), and few studies of the importance of HSP27 in esophagitis have been carried out in animal models. This study aimed to explore the expression of HSP27 in the esophageal tissue of rats with RE.</p><p><b>METHODS</b>Eighty female Wistar rats were randomly divided into experimental groups A and B and control groups C and D (n = 20 in each group). To establish RE, rats in the two experimental groups received pylorus and forestomach ligations, while rats in the control group received gastrostomy and gastric perforation repair. The rats in groups A and C were sacrificed 7 days after surgery, and the rats in groups B and D were sacrificed 14 days after surgery. In groups A and B, 10 and 8 rats were diagnosed with RE by pathological examination, respectively (they were included in groups A' and B', respectively). The histopathological diagnosis of all the lower esophageal tissues in groups C and D was normal and 20 normal specimens were randomly selected for groups C' and D' with 10 specimens in each group. Macroscopic and microscopic esophagitis scores were assessed for the specimens in groups A' and B'. Lower esophageal tissues were collected from groups A', B', C', and D', and paraffin-embedded slices were made using part of the tissues. The expression of HSP27 in the tissues was detected using the two-step streptavidin-peroxidase immunohistochemical method. Some collected tissues were frozen, and expressions of HSP27 mRNA were detected using fluorescence quantitative polymerase chain reaction (FQ-PCR).</p><p><b>RESULTS</b>Median macroscopic and microscopic esophagitis scores in groups A' (n = 10) and B' (n = 8) were 1.0 and 1.5, and 2.0 and 2.5, respectively. There were no significant differences in the macroscopic or microscopic esophagitis scores between the two groups (Z = -0.330, P = 0.741; Z = -0.142, P = 0.887, respectively). Immunohistochemical staining showed that HSP27 was expressed in all layers of the esophageal epithelia in RE and control rats. FQ-PCR showed that HSP27 mRNA levels in the lower esophageal tissue in RE group (groups A' and B') were higher than those in control group (groups C' and D') (Z = -0.249, P = 0.001). HSP27 mRNA expression in the lower esophageal tissue was significantly different in groups B' and D' (Z = -3.027, P = 0.002). And the levels of HSP27 mRNA expression in severe RE group (microscopic esophagitis score: 3) were higher than in mild RE group (microscopic esophagitis score: 1-2) and control group (Z = -3.396, P = 0.001; Z = -3.855, P < 0.001).</p><p><b>CONCLUSIONS</b>HSP27 mRNA expression in the lower esophageal tissue of rats with RE is significantly higher than in the normal controls. Although reflux is a persistent stimulating factor, increased expression of HSP27 in the lower esophageal tissue of rats with RE requires aggravated esophageal injury.</p>

Changes of serum cytokine caused by acute paraquat poisoning / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To observe the change of cytokine interleukin IL-1 beta, IL-6, IL-10, tumor necrosis factor-alpha (TNF-alpha) occurred in acute paraquat (PQ) poisoning rats and to investigate the mechanism of acute lung injury caused by paraquat (PQ) poisoning.</p><p><b>METHODS</b>All 72 healthy adult Wistar rats were random assigned into normal control groups, paraquat high dose group (120 mg/kg), paraquat middle dose (60 mg/kg) group, paraquat low dose group (30 mg/kg). Three observing periods of time included 8, 24, 72 h and the standards of TNF-alpha, IL-1 beta, IL-6, IL-10 were determined.</p><p><b>RESULTS</b>Every index of the PQ group was significantly higher than that in the NS group at the same period of time (P<0.05 or P<0.01). In the 72 h group, the high dose group was significantly higher than the middle and low dose group (P<0.05), and there was no significantly difference between the middle and low dose group (P>0.05). For the comparison of index in the same dose group, the group of 72 h was much higher than 8 h group and 24 h group (P<0.05), and there was no difference between the 8h group and 24 h group (P>0.05).</p><p><b>CONCLUSION</b>The cytokine may play an important role in paraquat-induced acute lung tissue injury.</p>

Study of embryonic stem cells induced to express hepatic cell functions in vitro in a pathologic niche containing cholestatic serum / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the role of a pathologic niche inducing mouse embryonic stem cells (ESC) to express hepatic cell functions in vitro.</p><p><b>METHODS</b>Embryoid bodies were developed from 5 to 7 day hanging-drop culture of mouse ESC, and their dissociated cells were planted in three differential systems: nothing added; with 20 ng/ml hepatocyte growth factor (HGF); and 5% rat cholestatic serum plus 20 ng/ml HGF added. Their differentiation was observed with inverted microscopes daily, and their hepatic functions were analyzed against their synthesis of glycogen, triglycerides, albumin, and urea nitrogen, and by their staining of indocyanine green (ICG) and fluorescein diacetate (FDA).</p><p><b>RESULTS</b>ESC spontaneous differentiation was hardly being controlled to form three germ layers. HGF prompted the ESC to develop further into visceral endoderm and mesoderm (myocardium), but both of them only expressed a low level of hepatocyte-specific metabolic functions. With cholestatic serum added into the HGF-induced system, differentiated cells grew into similar angular cells, and had a higher level synthesis of glycogen, triglycerides, albumin and urea nitrogen with positive ICG and FDA staining.</p><p><b>CONCLUSIONS</b>Spontaneous or HGF-induced ESC differentiation has only limited hepatic functions expressed. A pathologic niche in vitro induces ESC to develop into hepatic lineages, with a higher level of hepatic metabolic functions.</p>