Salt-tolerant and thermostable mechanisms of an endoglucanase from marine Aspergillus niger

The cellulase cocktail of marine Aspergillus niger exhibited salt-tolerant and thermostable properties, which is of great potential in industrial application. In order to excavate the single tolerant cellulase components from complex cellulase cocktail, constitutive homologous expression was employed for direct obtainment of the endoglucanase (AnEGL). Enzymatic property study revealed that AnEGL exhibited a property of salt tolerance and a strong thermostability in high salinity environment. Significantly, its activity increased to 129% and the half-life at 65 °C increased to 27.7-fold with the presence of 4.5 M NaCl. Molecular dynamics simulation revealed that Na+ and Cl- could form salt bridges with charged residues, and then influenced the activity of loops and the stability of substrate binding pocket, which accounted for the salt tolerance and thermostability. Further, site-specific mutagenesis study proved that the residues Asp95 and Asp99 in the pocket were of great concern for the tolerant properties. The salt-tolerant and thermostable AnEGL was of great value in lignocellulosic utilization and the conjectural mechanisms were of referential significance for other tolerant enzymes.

Interleukin-1β-Treated Mesenchymal Stem Cells Inhibit Inflammation in Hippocampal Astrocytes Through Exosome-Activated Nrf-2 Signaling

BACKGROUND

Interleukin-1β (IL-1)-treated mesenchymal stem cells (MSCs) and IL-1-MSCs-conditioned medium (CM) exert anti-inflammatory roles. Astrocytes are essential for the modulation of synaptic activity and neuronal homeostasis in the brain. Exosomes are the critical mediators in intercellular communication. However, the mechanism underlying the anti-inflammatory effect of IL-1-treated MSCs remains unknown.

METHODS

In this study, exosomes (IL-1-Exo) were isolated from IL-1-treated MSCs. In addition, lipopolysaccharide (LPS)-treated hippocampal astrocytes and status epilepticus (SE) mice were treated with IL-1-Exo. Inflammatory activity, astrogliosis, and cognitive performance were measured to determine the effect of IL-1-Exo on inflammation.

RESULTS

The results revealed that IL-1-Exo significantly inhibited LPS-induced astrogliosis and inflammatory responses of astrocytes. Also, IL-1-Exo reversed the LPS-induced effect on calcium signaling. The Nrf2 signaling pathway was associated with the effect of IL-1-Exo in LPS-treated astrocytes. Furthermore, IL-1-Exo reduced the inflammatory response and improved the cognitive performance of SE mice.

CONCLUSION

The results suggest that IL-1-Exo inhibited LPS-induced inflammatory responses in astrocytes and SE mice and that the effect of IL-1-Exo was primarily mediated through the Nrf-2 signaling pathway. This study provides a new understanding of the molecular mechanism of inflammation-associated brain diseases and an avenue to develop nanotherapeutic agents for the treatment of inflammatory conditions in the brain.

Cross electro-nape-acupuncture ameliorates cerebral hemorrhage-induced brain damage by inhibiting necroptosis

BACKGROUND

Receptor interacting protein kinase 1 (RIPK1)-mediated cell death, including apoptosis and necroptosis, belongs to programmed cell death. It has been reported that RIPK1-mediated necroptosis exists in lesions of cerebral hemorrhage (CH). Electroacupuncture, a treatment derived from traditional Chinese medicine, could improve neurological impairment in patients with brain injury.

AIM

To investigate the protective role of cross electro-nape acupuncture (CENA) in CH, and clarify the potential mechanism.

METHODS

CH rat models were established, and CENA was applied to the experimental rats. Neurological functions and encephaledema were then measured. Necrotic cells in the brain of rats with CH were evaluated by propidium iodide staining. Necroptosis was assessed by immunofluorescence. Activation of the necroptosis-related pathway was detected by western blot. Extraction of brain tissue, cerebrospinal fluid and serum samples was conducted to measure the expression and secretion of inflammatory cytokines by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay.

RESULTS

The necroptotic marker p-MLKL was detectable in the brains of rats with CH. Next, we found that CENA could ameliorate neurological functions in rat models of CH. Moreover, the upregulation of RIPK1-mediated necroptosis-related molecules in the brains of rats with CH were inhibited by CENA. Further investigation revealed that CENA partially blocked the interaction between RIPK1 and RIPK3. Finally, in vivo assays showed that CENA decreased the expression of the inflammatory cytokines tumor necrosis factor-α, interleukin-6 and interleukin-8 in CH rat models.

CONCLUSION

These findings revealed that CENA exerts a protective role in CH models by inhibiting RIPK1-mediated necroptosis.

[Association between serum Nε-carboxymethyl-lysine level and anterior tibial arterial plaque calcification in patients with diabetic foot post foot amputation]

Objective: To observe the correlation between Nε-carboxymethyl-Lysine (CML), the main component of advanced glycation end products and the calcification of the anterior tibial artery plaque in patients with diabetic foot post foot amputation. Methods: Sixty patients hospitalized for foot amputation operation due to diabetic foot from June 2012 to June 2016 in the Department of Orthopedics, Affiliated Hospital of Jiangsu University were prospectively recruited.The patients were categorized into mild stenosis (0<stenosis<50%, n=20), moderate stenosis (50%≤stenosis<70%, n=20) and severe stenosis (70%≤stenosis≤100%, n=20) based on the color Doppler ultrasound assessed severity of anterior tibial artery stenosis.The baseline clinical data of patients were collected and anterior tibial artery was isolated.Then, HE staining, O-Cresolphthalein Complexone method, enzymic method and ELASA analysis were then performed to detect the evolution of calcification, arterial calcium content, alkaline phosphatase activity and serum CML concentration, respectively. Results: The results from both color Doppler ultrasound scan before amputation and HE staining after amputation showed that echo intensity as well as spotty blue calcium particles of anterior tibial artery plaque increased significantly in proportion to degree of stenosis and destructed elastic plate of the arterial wall was evidenced in patients with severest stenosis.The content of calcium ((2.3±0.9), (3.9±1.3), (6.6±1.7) μmol/mg, respectively, P<0.001), ALP activity ((102.4±39.4), (202.3±73.4), (483.7±117.9) U/mg, respectively, P<0.001) and serum CML level ((28.9±4.4), (37.9±5.3), (57.3±7.1)μg/L, respectively, P<0.001) increased significantly in proportion to stenosis severity.Pearson correlation analysis showed that serum CML level was positively correlated with the content of calcium (r=0.749, P<0.001) and ALP activity (r=0.923, P<0.001), respectively. Conclusions: Serum CML level is positively correlated with the calcification of anterior tibial arterial plaque in patients with diabetic foot and could be used to evaluate the calcification of anterior tibial arterial plaque and stenosis degree of anterior tibial arterial in these patients.

Effects of hemoglobin variants HbJ Bangkok, HbE, HbG Taipei, and HbH on analysis of glycated hemoglobin via ion-exchange high-performance liquid chromatography

BACKGROUND

To explore the effects of HbJ Bangkok, HbE, HbG Taipei, and α-thalassemia HbH on the results of HbA1c assessment using ion-exchange high-performance liquid chromatography (IE-HPLC).

METHODS

We enrolled five patients in which the results of the IE-HPLC HbA1c assay were inconsistent with the average levels of FBG. We performed hemoglobin capillary (Hb) electrophoresis using whole-blood samples. We also sequenced the genes encoding Hb using dideoxy-mediated chain termination and analyzed HbA1c using borate affinity HPLC (BA-HPLC) and turbidimetric inhibition immunoassay (TINIA).

RESULTS

Two patients had the HbJ Bangkok variant. Hb genotypes of these patients were β^41-42 /β^{J Bangkok} and β^N /β^{J Bangkok} , and the content of HbJ Bangkok was 93.9% and 52.4%, respectively. The remaining three patients had the following: HbE (β^N /β^E Hb genotype, 23.6% HbE content), HbG Taipei (β^N /β^{G Taipei} Hb genotype, 39.4% HbG Taipei content), and α-thalassemia HbH (6.1% HbH content, 2.8% Hb Bart's content). In the patients with β-thalassemia and HbJ Bangkok variants, the presence of the variants interfered with the results of HbA1c analyses using IE-HPLC and TINIA; in the remaining four patients, there was interference with the results of HbA1c IE-HPLC but not with the TINIA assay. There was no interference with BA-HPLC HbA1c results.

CONCLUSIONS

HbJ Bangkok, HbE, HbG Taipei Hb, and α-thalassemia HbH disease cause varying degrees of interference with the analysis of HbA1c using IE-HPLC. In these patients, we suggest using methods free from such interference for the analysis of HbA1c and other indicators to monitor blood glucose levels.

Evaluation of the Interference of Hemoglobin Variant J-Bangkok on Glycated Hemoglobin (HbA1c) Measurement by Five Different Methods

Objective The interference of the hemoglobin variant (Hb J-Bangkok) was evaluated on 4 different glycated hemoglobin assays and compared with a reference immuno assay. Methods An overall test of coincidence of 2 least-squares linear regression lines was performed to determine whether the presence of Hb J-Bangkok caused a statistically significant difference in HbA1c results compared with a reference immuno assay. Statistical analysis was performed on the difference of the estimated average glucose calculated from HbA1c values and fasting plasma glucose in the Hb J-Bangkok variant group using the different detection systems. Deming regression analysis was used to determinate whether Hb J-Bangkok had a significant interference on HbA1c results using an HbA1c±10% relative bias at 6% and 9% HbA1c as evaluation limits. Results Turbidimetric inhibition immunoassay method, and enzymatic methods were not affected by Hb J-Bangkok. However, Hb J-Bangkok showed statistically significant interference to the two ion-exchange high-performance liquid chromatography methods. Conclusion When performing HbA1c tests, clinical laboratory personnel should identify the Hb variant and select the appropriate methods or use alternative indicators.

[Relief effect of CT-guided (125)I seed implantation on patients with spinal and paraspinal osteolytic metastatic tumors]

Objective: To evaluate the clinical value of computed tomography (CT)-guided (125)I seed implantation in the treatment of patients with spinal and/or paraspinal osteolytic metastatic tumors. Methods: The radiation dose distribution was planned for 27 patients with 35 spinal and paraspinal osteolytic metastatic tumors by a treatment planning system (TPS). CT-guided (125)I seed implantation was carried out in the patients, and the quality of treatment was evaluated based on CT-imaging follow-up. Results: All the 27 patients underwent CT-guided (125)I seed implantation successfully. 12 to 50 (125)I seeds were injected into each spinal or paraspinal metastatic tumor, 39.15 on average, and the specific radioactive activity of the particles ranged from 0.60 to 0.80 mCi, 0.73 mCi on average. The minimal percentage of the dose received by 90% of the target volume (D(90)) of the spinal and paraspinal metastatic tumors ranged from 90 to 165 Gy, 115.03 Gy on average. Among the 27 patients, 21 (77.8%) had partial remission (PR) and 6(22.2%)had stable disease (SD). The Numerical Rating Scale (NRS) scores before implantation and at postoperative 3 and 6 months were 7.81±0.74, 2.04±1.10 and 1.81±0.79, respectively, (P<0.05). The assessment of pain intensity before (125)I seed implantation and at 3 postoperative months showed obvious improvements in the patients evaluated according to the American Spinal Injury Association (ASIA) impairment scale: 12 (44.4%) patients with ASIA grade C were changed to grade D, 3 (11.1%) from grade C to grade E, 8 (29.6%) from grade D to grade E, 3 (11.1%) with a stable grade D, and 1 (3.7%)with a stablegrade C. The Karnovsky performance scale (KPS) scores before treatment and at 3 months and 6 months postoperatively were 66.30±6.88, 85.93±9.31 and 87.91±8.56, respectively (P<0.05). Their local control rate (LCR) at 3 months, 6 months and 1 year postoperatively were 100%, 92.6% and 51.9%, respectively, and the overall survival rates(OSR) were 100%, 92.6% and 55.6%, respectively. Conclusions: CT-guided (125)I seed implantation can significantly relieve local pain, has advantages of less complications and higher local control rate. Therefore, it is a safe, effective and feasible treatment option for patients with spinal and paraspinal osteolytic metastatic tumors.

[Effects of hemoglobin J-Bangkok traits on measurements of glycated hemoglobin by five methods]

OBJECTIVE

To evaluate the interference of hemoglobin variants J-Bangkok on glycated hemoglobin (HbA(1)c) detected by five measurement systems.

METHODS

Seventy cases of blood samples were collected at Zhongshan Hospital of Sun Yat-sen University from July 2012 to January 2014, the blood samples were divided into the normal control group (40 cases) and Hb J-Bangkok variant group (30 cases), and the normal control group was divided into healthy control group (20 cases) and diabetic group (20 cases). HbA(1)c measurement systems were Primus Ultra2, Variant Ⅱ, Variant Ⅱ Turbo, Modular P and Leadman. Based on the standard of the American National Glycosylated Hemoglobin Standardization Program (NGSP), Primus Ultra2 was used as comparative system, and the other 4 systems were test systems. Comparative analysis and bias evaluation were conducted on the results from five detection systems in different groups, statistical analysis were used for evaluating the differences. The estimated average glucose (eAG) was calculated by HbA(1)c values and fasting plasma glucose (FPG) of Hb J-Bangkok variant group with the different detection systems. Deming regression analysis was used to determinate whether Hb J-Bangkok produced significant clinical effect on HbA(1)c results. HbA(1)c ± 10% and relative bias at 6% and 9% HbA1c were evaluation limits.

RESULTS

The differences of the 95% confidence interval (95%CI) between the test systems and the comparative system in control group were within ±0.7% HbA(1)c, bias were less than 6%, there were no statistically significant difference (P>0.05). In Hb J-Bangkok group, the eAG calculated from HbA(1)c measured by using Primus Ultra2, Modular P and Leadman were (8.14±2.99), (8.10±3.06) and (8.23±3.00)mmol/L, which had no statistically significant difference compared with FPG ((8.21±3.12)mmol/L, t=0.996, 1.091, 1.479, all P>0.05), and the differences of 95%CI between the results measured by Modular P and the comparative system were all within ±0.7% HbA(1)c, bias were -4.3%-0.4% and -5.2%-4.9%, there were no statistically significant difference (P>0.05). At 6% and 9% HbA(1)c concentrations, the mean differences of the results from the three detection systems were less than the clinically acceptable range. These results showed that the systems of Primus Ultra2, Modular P and Leadman were not affected by Hb J-Bangkok. However, the eAG values calculated from HbA(1)c of Variant Ⅱ and Variant Ⅱ Turbo were (5.58±2.12) and(5.00±2.13)mmol/L, which showed statistically significant lower results compared with FPG level (t=12.29, 13.23 , all P<0.001). Compared with Primus Ultra2, the differences of 95%CI were outside of ± 0.7% HbA1c, bias were -31.9%--12.0% and -42.0%- -17.6% , greater than 6%, showed a negative bias.At 6% and 9% HbA(1)c concentrations, the mean differences of the results were all greater than the clinical acceptable range. These results indicated that Hb J-Bangkok had significantly clinical interference on Variant Ⅱ and Variant Ⅱ Turbo systems.

CONCLUSION

Hb J-Bangkok has different interference on different HbA(1)c measurement systems, when performs the HbA(1)c test, clinical laboratory should pay attention to identify Hb variants, and select the appropriate methods to measure the HbA(1)c values in order to prevent the occurrence of interference by Hb variants.

Isolation and characterization of novel polymorphic microsatellite markers for Lutjanus erythropterus

We isolated and characterized 22 polymorphic microsatellite loci in the crimson snapper (Lutjanus erythropterus) using a (GT)13-enriched genomic library. We found three to 15 alleles per locus, with a mean of 6.68. The observed and expected heterozygosities ranged from 0.087 to 0.978 and from 0.125 to 0.904, respectively, with averages of 0.576 and 0.650, respectively. Only three loci showed significant deviation from the Hardy-Weinberg equilibrium after Bonferroni correction. Four loci showed evidence for null alleles. These markers will be useful for analyzing the population genetic structure and gene flow of L. erythropterus.

Isolation and characterization of microsatellite loci in the purpleback flying squid (Sthenoteuthis oualaniensi)

The purpleback flying squid (Sthenoteuthis oualaniensis) is a pelagic squid with tremendous potential for commercial exploitation. We isolated and characterized 21 polymorphic microsatellite loci for S. oualaniensis using a (GT)13-enriched genomic library. The number of alleles per locus varied from 6 to 32. The observed and expected heterozygosities ranged from 0.188 to 0.890, and 0.537 to 0.968, respectively. No significant linkage disequilibrium was detected at these loci. Five loci significantly deviated from the Hardy-Weinberg equilibrium, and four loci may have exhibited null alleles. These microsatellite markers will facilitate further studies in population genetics and the sustainable utilization of S. oualaniensis.

Effect of adding gemtuzumab ozogamicin to induction chemotherapy for newly diagnosed acute myeloid leukemia: a meta-analysis of prospective randomized phase III trials

BACKGROUND

Gemtuzumab ozogamicin (GO) is a targeted antineoplastic agent comprised of a recombinant anti-CD33 humanized antibody linked to calicheamicin. Previous trials have showed conflicting results concerning the efficacy and toxicity of adding GO to induction chemotherapy for newly diagnosed acute myeloid leukemia (AML). A systematic review and meta-analysis was conducted to resolve this controversial issue.

PATIENTS AND METHODS

Summary data from five randomized phase III trials compared adding GO to induction chemotherapy with induction chemotherapy alone for newly diagnosed AML were meta-analyzed. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS) and relapse-free survival (RFS), and pooled odds ratios (ORs) and 95% CIs for complete remission (CR) rate, incidences of resistance disease, relapse and toxicity were calculated.

RESULTS

Data of 3596 patients (1798 GO and 1798 controls) from five randomized phase III trials were analyzed. Compared with induction chemotherapy alone, adding GO significantly prolonged OS (HR 0.93, 95% CI 0.86-1.00, P=0.05) and RFS (HR 0.87, 95% CI 0.79-0.95, P=0.003), decreased the incidences of resistant disease (OR 0.71, 95% CI 0.55-0.93, P=0.01) and relapse (OR 0.75, 95% CI 0.63-0.90, P=0.002), but had no effect on CR rate (OR 1.15, 95% CI 0.91-1.46, P=0.24). Sensitivity analysis yielded similar results. Subgroup analysis identified that cytogenetics might be an influencing factor for the effect of adding GO. In addition, the risks of grade 3-4 nausea/vomiting, diarrhea and liver aspartate transaminase (AST) elevation were increased in GO arm.

CONCLUSIONS

Adding GO to induction chemotherapy for newly diagnosed AML can significantly prolong OS and RFS, decrease incidences of resistant disease and relapse, but may increase risks of grade 3-4 nausea/vomiting, diarrhea and liver AST elevation.

Polymorphic microsatellite loci for the crimson snapper (Lutjanus erythropterus)

We isolated and characterized 22 polymorphic microsatellite loci in Lutjanus erythropterus using a (GT)13-enriched genomic library. We found between 2 and 8 alleles per locus, with a mean of 4.85. The observed and expected heterozygosities ranged from 0.065 to 0.867 and from 0.085 to 0.832, respectively, with means of 0.461 and 0.529, respectively. Allele frequencies in three loci were found to deviate from Hardy-Weinberg equilibrium. Evidence for null alleles was found for three loci. These markers will be useful for distinguishing released captive-bred L. erythropterus individuals from wild individuals.

Polymorphic microsatellite loci isolated from the yellowbelly threadfin bream, Nemipterus bathybius

Twenty-two polymorphic microsatellite loci were isolated and characterized from a (GT)13-enriched Nemipterus bathybius genomic library. The number of alleles per locus ranged from 4 to 13, with an average of 7.86. The observed and expected heterozygosity was 0.167-0.889 and 0.278-0.904, respectively, with averages of 0.590 and 0.690. Three loci deviated from Hardy-Weinberg proportions, and 2 loci showed evidence of null alleles. No significant linkage disequilibrium was detected in the pairwise comparisons among the 22 loci. These markers are expected to be useful for the population genetic analysis of N. bathybius.

[Effect of pressure on electron-phonon coupling constants of all-trans-beta-carotene]

The present paper cited that R Tubino and other people introduced a kind of electron-phonon coupling constants with dimension, which can establish the relation with the Huang-Rhys factor and calculate the electron-phonon coupling constants of every C-C bond vibration mode. There are many reports about the visible absorption and Raman spectra of all-trans-beta-carotene with pressure. But the study about the Raman scattering cross section and the Huang-Rhys factor with pressure have not been reported now. Visible absorption and Raman spectra of all-trans-beta-carotene were measured in carbon disulfide in the pressure range from 0. 04 to 0. 60 GPa. The results indicated that the visible absorption spectra of beta-carotene in nonpolar solvent carbon disulfide are red-shifted with pressure increasing, but the frequency shifts towards higher frequencies in the Raman spectra, the Raman scattering cross section decreases, Huang-Rhys factor increases, and the electron-phonon coupling constants of CC bond vibration modes increase. The mechanism is that all-trans-beta-carotene caused by compression and a decrease in the structurally ordered properties of the molecules leads to narrow energy gap of the pi, shortens effective conjugation length, hinders delocalization of pi-electron, decreases the Raman scattering cross section, and increases the Huang-Rhys factor and the electron-phonon coupling constants.

Effects of sodium ferulate on liver fibrosis in experimental cirrhotic rats

AIM: To assess the effects of sodium ferulate on liver fibrosis in rats with experimental cirrhosis induced by bile duct ligation.

METHODS: Liver cirrhosis was experimentally induced in rats by bile duct ligation. Rats were divided into three groups: a control group, a model group and a treatment group, which were treated by sham-operation, bile duct ligation, and sodium ferulate injection after bile duct ligation, respectively. Biochemical parameters were measured. Body weight, liver weight and liver index were compared between groups. Pathological characteristics of liver tissues were observed by optical microscopy and transmission electron microscopy, and the integrated absorbance of hepatic α-smooth muscle actin was determined by immunohistochemistry.

RESULTS: Biochemical parameters did not differ between the model group and treatment group. Liver index in the model group increased compared with control rats (7.83% ± 0.57% vs 4.05% ± 0.17%, P < 0.01); after treatment, the index decreased significantly (7.08% ± 0.68% vs 7.83% ± 0.57%, P < 0.05). Pathological observation revealed that the degree of fibrosis and severity of hepatocyte damage in the treatment group were lower than those in the model group. Hepatic α-SMA content in the model group was significantly higher than that in the control group (113224.74 ± 45518.79 vs 4197.80 ± 1364.97, P < 0.01). After treatment with sodium ferulate, hepatic α-SMA content decreased in the treatment group compared with the model group (46451.65 ± 15600.56 vs 113224.74 ± 45518.79, P < 0.05).

CONCLUSION: Sodium ferulate has a therapeutic effect on liver fibrosis in rats with experimental cirrhosis induced by bile duct ligation.

Acute pancreatitis secondary to primary liver cancer with hemobilia: A case report and literature review

Primary liver cancer (PLC) may lead to many complications. The formation of bile tumor thrombi in the bile duct of patients with PLC is not a rare clinical condition; however, hemobilia and acute pancreatitis caused by bile duct thrombus formation in PLC patients are very rare. Here we report such a case in a 48-year-old female and perform a review of the literature on the diagnosis and treatment of this rare disorder. Endoscopic retrograde cholangiopancreatography (ERCP) and transcatheter hepatic arterial chemoembolization (TACE) are very important for the early diagnosis and treatment of this condition.

Response gene to complement-32 enhances metastatic phenotype by mediating transforming growth factor beta-induced epithelial-mesenchymal transition in human pancreatic cancer cell line BxPC-3

BACKGROUND

Response gene to complement-32 (RGC-32) is comprehensively expressed in many kinds of tissues and has been reported to be expressed abnormally in different kinds of human tumors. However, the role of RGC-32 in cancer remains controversial and no reports have described the effect of RGC-32 in pancreatic cancer. The present study investigated the expression of RGC-32 in pancreatic cancer tissues and explored the role of RGC-32 in transforming growth factor-beta (TGF-β)-induced epithelial-mesenchymal transition (EMT) in human pancreatic cancer cell line BxPC-3.

METHODS

Immunohistochemical staining of RGC-32 and E-cadherin was performed on specimens from 42 patients with pancreatic cancer, 12 with chronic pancreatitis and 8 with normal pancreas. To evaluate the role of RGC-32 in TGF-β-induced EMT in pancreatic cancer cells, BxPC-3 cells were treated with TGF-β1, and RGC-32 siRNA silencing and gene overexpression were performed as well. The mRNA expression and protein expression of RGC-32 and EMT markers such E-cadherin and vimentin were determined by quantitative reverse transcription-PCR (qRT-PCR) and western blot respectively. Finally, migration ability of BxPC-3 cells treated with TGF-β and RGC-32 siRNA transfection was examined by transwell cell migration assay.

RESULTS

We found stronger expression of RGC-32 and higher abnormal expression rate of E-cadherin in pancreatic cancer tissues than those in chronic pancreatitis tissues and normal pancreatic tissues. Immunohistochemical analysis revealed that both RGC-32 positive expression and E-cadherin abnormal expression in pancreatic cancer were correlated with lymph node metastasis and TNM staging. In addition, a significant and positive correlation was found between positive expression of RGC-32 and abnormal expression of E-cadherin. Furthermore, in vitro, we found sustained TGF-β stimuli induced EMT and up-regulated RGC-32 expression in BxPC-3 cells. By means of siRNA silencing and gene overexpression, we further demonstrated that RGC-32 mediated TGF-β-induced EMT and migration in BxPC-3 cells.

CONCLUSIONS

The results above indicated that RGC-32 might be a novel metastasis promoting gene in pancreatic cancer and it enhances metastatic phenotype by mediating TGF-β-induced EMT in human pancreatic cancer cell line BxPC-3.