Long non-coding RNA TP73-AS1 promotes pancreatic cancer growth and metastasis through miRNA-128-3p/GOLM1 axis.

BACKGROUND: Previous studies have suggested that long non-coding RNAs (lncRNA) TP73-AS1 is significantly upregulated in several cancers. However, the biological role and clinical significance of TP73-AS1 in pancreatic cancer (PC) remain unclear. AIM: To investigate the role of TP73-AS1 in the growth and metastasis of PC. METHODS: The expression of lncRNA TP73-AS1, miR-128-3p, and GOLM1 in PC tissues and cells was detected by quantitative real-time polymerase chain reaction. The bioinformatics prediction software ENCORI was used to predict the putative binding sites of miR-128-3p. The regulatory roles of TP73-AS1 and miR-128-3p in cell proliferation, migration, and invasion abilities were verified by Cell Counting Kit-8, wound-healing, and transwell assays, as well as flow cytometry and Western blot analysis. The interactions among TP73-AS1, miR-128-3p, and GOLM1 were explored by bioinformatics prediction, luciferase assay, and Western blot. RESULTS: The expression of TP73-AS1 and miRNA-128-3p was dysregulated in PC tissues and cells. High TP73-AS1 expression was correlated with a poor prognosis. TP73-AS1 silencing inhibited PC cell proliferation, migration, and invasion in vitro as well as suppressed tumor growth in vivo. Mechanistically, TP73-AS1 was validated to promote PC progression through GOLM1 upregulation by competitively binding to miR-128-3p. CONCLUSION: Our results demonstrated that TP73-AS1 promotes PC progression by regulating the miR-128-3p/GOLM1 axis, which might provide a potential treatment strategy for patients with PC.

Expression of FoxM1 and the EMT-associated protein E-cadherin in gastric cancer and its clinical significance.

The aim of the present study was to investigate the expression of forkhead box M1 (FoxM1) and E-cadherin in tissues of gastric cancer in order to reveal any correlation between FoxM1, E-cadherin and clinicopathological parameters. The association between FoxM1 and E-cadherin in the development and progression of gastric cancer was also investigated. The expression of FoxM1 and E-cadherin in gastric cancer and adjacent normal tissue on tissue microarray was detected using immunohistochemistry. The clinicopathological significance of FoxM1 and E-cadherin in gastric cancer was explored, and the association between FoxM1 and E-cadherin was further examined using statistical techniques. In gastric cancer tissues, the expression of FoxM1 and E-cadherin was strongly positive, but it was weak in normal gastric mucosa. Overexpression of FoxM1 was evident in gastric cancer, and was associated with poor tumor differentiation (P<0.05), advanced tumor state (P<0.05) and lymph node (or distant) metastasis (P<0.05), whereas E-cadherin had the opposite effects. Furthermore, the correlation between FoxM1 and E-cadherin expression in gastric cancer tissue was negative. In conclusion, the high FoxM1 expression and low E-cadherin expression in gastric cancer tissue suggests that these proteins play a critical role in the development and progression of gastric cancer.

Clinical comparison of laparoscopy vs open surgery in a radical operation for rectal cancer: A retrospective case-control study.

AIM: To assess the diverse immediate and long-term clinical outcomes, a retrospective comparison between laparoscopic and conventional operation was performed. METHODS: A total number of 916 clinical cases, from January 2006 to December 2013 in our hospital, were analyzed which covered 492 patients underwent the laparoscopy in radical resection (LRR) and 424 cases in open radical resection (ORR). A retrospective analysis was proceeded by comparing the general information, surgery performance, pathologic data, postoperative recovery and complications as well as long-term survival to investigate the diversity of immediate and long-term clinical outcomes of laparoscopic radical operation. RESULTS: There were no statistically significance differences between gender, age, height, weight, body mass index (BMI), tumor loci, tumor node metastasis stages, cell differentiation degree or American Society of Anesthesiologists scores of the patients (P > 0.05). In contrast to the ORR group, the LRR group experienced less operating time (P < 0.001), a lower blood loss (P < 0.001), and had a 2.44% probability of conversion to open surgery. Postoperative bowel function recovered more quickly, analgesic usage and the average hospital stay (P < 0.001) were reduced after LRR. Lymph node dissection during LRR appeared to be slightly more than in ORR (P = 0.338). There were no obvious differences in the lengths and margins (P = 0.182). And the occurrence rate in the two groups was similar (P = 0.081). Overall survival rate of ORR and LRR for 1, 3 and 5 years were 94.0% and 93.6% (P = 0.534), 78.1% and 80.9% (P = 0.284) and 75.2% and 77.0% (P = 0.416), respectively. CONCLUSION: Laparoscopy as a radical operation for rectal cancer was safe, produced better immediate outcomes. Long-term survival of laparoscopy revealed that it was similar to the open operation.

Application of international videoconferences for continuing medical education programs related to laparoscopic surgery.

BACKGROUND: Continuing medical education (CME) is an effective way for practicing physicians to acquire up-to-date clinical information. MATERIALS AND METHODS: We conducted four CME seminars in 2007-2010 endorsed by the Chinese Medical Association Council on Medical Education. Overseas telelectures and live case demonstrations were introduced in each seminar via telemedicine based on a digital video transport system. Network stability and packet loss were recorded. An anonymous mini-questionnaire was conducted to evaluate the satisfaction of attendees regarding the image and sound quality, content selection, and overall evaluation. RESULTS: Four telelectures and five live case demonstrations were successfully conducted. Stability of the network was maintained during each videoconference. High-quality videos of 720 × 480 pixels at the rate of 30 frames per second were shown to the entire group of attendees. The time delay between Shanghai and Fukuoka, Japan, was only 0.3 s, and the packet loss was 0%. We obtained 129 valid responses to the mini-questionnaire from a total of 146 attendees. The majority of the attendees were satisfied with the quality of transmitted images and voices and with the selected contents. The overall evaluation was ranked as excellent or good. CONCLUSIONS: Videoconferences are excellent channels for CME programs associated with laparoscopic training.

STAT3 knockdown reduces pancreatic cancer cell invasiveness and matrix metalloproteinase-7 expression in nude mice.

AIMS: Transducer and activator of transcription-3 (STAT3) plays an important role in tumor cell invasion and metastasis. The aim of the present study was to investigate the effects of STAT3 knockdown in nude mouse xenografts of pancreatic cancer cells and underlying gene expression. METHODS: A STAT3 shRNA lentiviral vector was constructed and infected into SW1990 cells. qRT-PCR and western immunoblot were performed to detect gene expression. Nude mouse xenograft assays were used to assess changes in phenotypes of these stable cells in vivo. HE staining was utilized to evaluate tumor cell invasion and immunohistochemistry was performed to analyze gene expression. RESULTS: STAT3 shRNA successfully silenced expression of STAT3 mRNA and protein in SW1990 cells compared to control cells. Growth rate of the STAT3-silenced tumor cells in nude mice was significantly reduced compared to in the control vector tumors and parental cells-generated tumors. Tumor invasion into the vessel and muscle were also suppressed in the STAT3-silenced tumors compared to controls. Collagen IV expression was complete and continuous surrounding the tumors of STAT3-silenced SW1990 cells, whereas collagen IV expression was incomplete and discontinuous surrounding the control tumors. Moreover, microvessel density was significantly lower in STAT3-silenced tumors than parental or control tumors of SW1990 cells. In addition, MMP-7 expression was reduced in STAT3-silenced tumors compared to parental SW1990 xenografts and controls. In contrast, expression of IL-1ß and IgT7α was not altered. CONCLUSION: These data clearly demonstrate that STAT3 plays an important role in regulation of tumor growth, invasion, and angiogenesis, which could be act by reducing MMP-7 expression in pancreatic cancer cells.

Down-regulation of STAT3 expression by vector-based small interfering RNA inhibits pancreatic cancer growth.

AIM: To evaluate the effect of RNA interference (RNAi) mediated silence of signal transduction and activation of transcription (STAT)3 on the growth of human pancreatic cancer cells both in vitro and in vivo. METHODS: STAT3 specific shRNA was used to silence the expression of STAT3 in pancreatic cancer cell line SW1990. The anti-growth effects of RNAi against STAT3 were studied in vitro and in experimental cancer xenografts in nude mice. The potential pathways involved in STAT3 signaling were detected using reverse transcription polymerase chain reaction and western blotting. RESULTS: The expression of the STAT3 was inhibited using RNAi in SW1990 cells. RNAi against STAT3 inhibited cell proliferation, induced cell apoptosis and significantly reduced the levels of CyclinD1 and Bcl-xL when compared with parental and control vector-transfected cells. In vivo experiments showed that RNAi against STAT3 inhibited the tumorigenicity of SW1990 cells and significantly suppressed tumor growth when it was directly injected into tumors. CONCLUSION: STAT3 signaling pathway plays an important role in the progression of pancreatic cancer, and silence of STAT3 gene using RNAi technique may be a novel therapeutic option for treatment of pancreatic cancer.

Individual recognition and odor in rat-like hamsters: behavioral responses and chemical properties.

Individual recognition has been studied across a number of taxa and modalities; however, few attempts have been made to combine chemical and biological approaches and arrive at a more complete understanding of the use of secretions as signals. We combined behavioral habituation experiments with gas chromatography-mass spectrometry of glandular secretions from the left and right flank gland and midventral gland of the rat-like hamster, Tscheskia triton. We found that females became habituated to one scent and then could discriminate individuals via another scent source from the same individual only when familiar with the scent donor. However, this prior social interaction was not required for females to discriminate different individuals in single-stimulus habituation-dishabituation tests. Chemical analyses revealed a similarity in volatile compounds between the left and right flank gland and midventral gland scents. It appears that individually distinctive cues are integratively coded by a combination of both flank gland and midventral gland secretions, instead of a single scent, albeit animals show different preferences to the novel scent. Our results suggest that odors from the flank and midventral glands may provide information related to individuality and aid individual recognition in this species and confirm that prior interaction between individuals is a prerequisite for rat-like hamsters to form multi-odor memory of a particular conspecific.

STAT3-targeting RNA interference inhibits pancreatic cancer angiogenesis in vitro and in vivo.

Signal transducers and activators of transcription 3 (STAT3) is a central cytoplasmic transcription factor that is activated by phosphorylation in response to extracellular signals and oncogenes. STAT3 regulates a number of pathways important in tumorigenesis including cell cycle progression, apoptosis, tumor angiogenesis, invasion and metastasis, and tumor cell evasion of the immune system. Our studies demonstrated that constitutively activated STAT3 plays an important role in the angiogenesis of pancreatic cancer. The objective of this study was to evaluate the potential use of RNA interference (RNAi) to knock down the STAT3 gene and the effect on angiogenesis of human pancreatic cancer cells in vitro and in vivo. We stably inhibited the expression of STAT3 and phosphorylated STAT3 (p-STAT3) using RNAi in the SW1990 pancreatic cancer cell line. Furthermore, RNAi for STAT3 inhibited STAT3-induced HUVEC cell migration and cell proliferation, and significantly suppressed the levels of secreted vascular endothelial growth factor (VEGF) and matrix metalloproteinases-2 (MMP-2) of SW1990 cells. In vivo experiments showed that RNAi for STAT3 significantly suppressed tumor growth and angiogenesis of SW1990 cells. Furthermore, silencing the STAT3 gene in SW1990 cells by RNAi also led to a decrease of VEGF and MMP-2 at the mRNA and protein levels. Collectively, these results demonstrate that the STAT3 signaling pathway plays an important role in the angiogenesis of pancreatic cancer and that knockdown of the STAT3 gene using the RNAi technique may be a novel therapeutic option for the treatment of pancreatic cancer.

Lentivirus-mediated shRNA interference targeting STAT3 inhibits human pancreatic cancer cell invasion.

AIM: To investigate RNA interference targeting signal transducer and activator of transcription-3 (STAT3) on invasion of human pancreatic cancer cells. METHODS: We constructed three plasmids of RNA interference targeting the STAT3 gene. After LV (lentivirus)-STAT3siRNA (STAT3 small interfering RNA) the vector was transfected into the human pancreatic cell line, SW1990 and cell proliferation was measured by the MTT assay. Flow cytometry was used to assess cell cycle. Vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2 (MMP-2) mRNA and protein expression were examined by quantitative PCR and western blotting, respectively. The invasion ability of SW1990 cells was determined by cell invasion assay. RESULTS: We successfully constructed the LV-STAT3siRNA lentivirus vector and proved that it can suppress expression of STAT3 gene in SW1990 cells. RNA interference of STAT3 by the LV-STAT3siRNA construct significantly inhibited the growth of SW1990 cells, in addition to significantly decreasing both VEGF and MMP-2 mRNA and protein expression. Moreover, suppression of STAT3 by LV-STAT3siRNA decreased the invasion ability of SW1990 cells. CONCLUSION: The STAT3 signaling pathway may provide a novel therapeutic target for the treatment of pancreatic cancer since it inhibits the invasion ability of pancreatic cancer cells.

[Effect of RNAi-mediated STAT3 gene inhibition on metastasis of human pancreatic cancer cells].

OBJECTIVE: To investigate the effect of RNAi-mediated STAT3 gene inhibition on metastasis of human pancreatic cancer cells and its underlying mechanism. METHODS: STAT3 shRNA expression vector was constructed and transfected into SW1990 cells. STAT3 mRNA and STAT3 DNA-binding activity were examined using reverse transcription polymerase chain reaction (RT-PCR) and electrophoretic mobility shift assay (EMSA), respectively. The metastasis ability of SW1990 cells in vivo was determined in acute hematogenous metastasis model using nude mice. RT-PCR was performed to detect the mRNA expression of the MMP-2 and VEGF. RESULTS: The mRNA expression of STAT3 and STAT3 DNA-binding activity were inhibited significantly by stable transfection of STAT3 shRNA expressing vectors. RNAi inhibition of STAT3 significantly suppressed the metastasis ability of SW1990 cells in vivo, and also markedly reduced the mRNA expression of MMP-2 and VEGF in SW1990 cells. CONCLUSIONS: Inhibition of STAT3 by RNAi significantly inhibits the metastasis ability of pancreatic cancer cells through down-regulation of MMP-2 and VEGF, and may provide a novel strategy for preventing the metastasis of pancreatic cancer.

Uncompressed video image transmission of laparoscopic or endoscopic surgery for telemedicine.

Traditional narrowband telemedicine cannot provide quality dynamic images. We conducted videoconferences of laparoscopic and endoscopic operations via an uncompressed video transmission technique. A superfast broadband Internet link was set up between Shanghai in the People's Republic of China and Fukuoka in Japan. Uncompressed dynamic video images of laparoscopic and endoscopic operations were transmitted by a digital video transfer system (DVTS). Seven teleconferences were conducted between June 2005 and June 2007. Of the 7 teleconferences, 5 were live surgical demonstrations and 3 were recorded video teleconsultations. Smoothness of the motion picture, sharpness of images, and clarity of sound were benefited by this form of telemedicine based upon DVTS. Telemedicine based upon DVTS is a superior choice for laparoscopic and endoscopic skill training across the borders.

Expression of hypoxia-inducible factor-1 alpha and associated proteins in pancreatic ductal adenocarcinoma and their impact on prognosis.

The aim of this study was to assess the significance of expression of hypoxia-inducible factor-1alpha (HIF-1alpha) and associated proteins in pancreatic ductal adenocarcinoma (PDA) and their impact on prognosis. Expression of HIF-1alpha, vascular endothelial growth factor (VEGF), glucose transporter-1 (Glut-1), survivin, CD34 and Ki-67 and apoptotic cells was demonstrated by immunohistochemistry or TUNEL in 58 PDAs and 20 normal pancreatic tissue samples. Our results show positivity of HIF-1alpha, VEGF, Glut-1 and survivin in 70.7%, 77.6%, 67.2% and 84.5% of the patients with PDA, respectively, which is significantly higher than in the normal counterparts. Expression of HIF-1alpha correlated positively with VEGF and Glut-1 expression but not with survivin. Strong HIF-1alpha expression associated with decreased apoptotic index and increased intratumoral microvessel density. Higher HIF-1alpha, VEGF and Glut-1 expression significantly associated with advanced tumor stage and lymph node metastasis. Patients with high HIF-1alpha, VEGF and Glut-1 expressing tumors had a poorer overall survival. Furthermore, Cox regression analysis showed that HIF-1alpha is a prognostic marker of borderline significance while VEGF was important in predicting poor outcome. These results suggest that over-expression of HIF-1alpha may play an important role in cancer progression through up-regulation of VEGF and Glut-1 in PDA patients. HIF-1alpha and VEGF are potential candidates for predicting survival.

[Inhibitory effect of AG490 on invasion and metastasis of human pancreatic cancer cells in vitro].

OBJECTIVE: To investigate the effect and mechanism of blockade of STAT3 signaling pathway by JAK specific inhibitor-AG490 on invasion and metastasis of human highly metastatic pancreatic cancer line SW1990 in vitro. METHODS: AG490 was added into the culture media for SW1990 cells. The invasion ability of SW1990 cells was determined by cell invasion assay kit. Western blot was performed to detect the protein expression of the STAT3, phosphorylated STAT3 (p-STAT3), MMP-2 and VEGF. RT-PCR was performed to detect the mRNA expression of the MMP-2 and VEGF. RESULTS: 20 micromol/L AG490 significantly inhibited the invasion ability of SW1990 cells and the inhibitory rate of invasion ability was (77.67 +/- 7.79) %. The use of AG490 not only markedly reduced the protein expression of p-STAT3, MMP-2 and VEGF, but also greatly reduced the mRNA expression of MMP-2 and VEGF. CONCLUSION: Blocking STAT3 activation with AG490 can inhibit the invasion and metastasis ability of pancreatic cancer cells in vitro through down-regulation of MMP-2 and VEGF expression. Blocking STAT3 signaling pathway may provide a novel strategy in prevention of invasion and metastasis of pancreatic cancer.