Insights into the history and tendency of glycosylation and digestive system tumor: A bibliometric-based visual analysis

BACKGROUND

Glycosylation, a commonly occurring post-translational modification, is highly expressed in several tumors, specifically in those of the digestive system, and plays a role in various cellular pathophysiological mechanisms. Although the importance and detection methods of glycosylation in digestive system tumors have garnered increasing attention in recent years, bibliometric analysis of this field remains scarce. The present study aims to identify the developmental trends and research hotspots of glycosylation in digestive system tumors.

AIM

To find and identify the developmental trends and research hotspots of glycosylation in digestive system tumors.

METHODS

We obtained relevant literature from the Web of Science Core Collection and employed VOSviewer 1.6.19 and CiteSpace (version 6.1.R6) to perform bibliometric analysis.

RESULTS

A total of 2042 documents spanning from 1978 to the present were analyzed, with the research process divided into three phases: the period of obscurity (1978-1990), continuous development period (1991-2006), and the rapid outbreak period (2007-2023). These documents were authored by researchers from 66 countries or regions, with the United States and China leading in terms of publication output. Reis Celso A had the highest number of publications, while Pinho SS was the most cited author. Co-occurrence analysis revealed the most popular keywords in this field are glycosylation, expression, cancer, colorectal cancer, and pancreatic cancer. Furthermore, the Journal of Proteome Research was the most prolific journal in terms of publications, while the Journal of Biological Chemistry had the most citations.

CONCLUSION

The bibliometric analysis shows current research focus is primarily on basic research in this field. However, future research should aim to utilize glycosylation as a target for treating tumor patients.

[Circular RNA-Encoded Proteins in Gastrointestinal Cancer:A Review]

Circular RNAs(CircRNAs)are a class of non-coding RNAs with a covalently closed-loop structure,high stability,and tissue specificity,with the production mechanisms different from linear RNAs.Recent studies have discovered that some CircRNAs can encode proteins via cap-independent translation mechanisms such as internal ribosome entry site,N6-methyladenosine,and rolling loop translation.The encoded proteins regulate homologous linear proteins or downstream signaling pathways via protein bait or other mechanisms,thereby exerting biological functions.Studies have shown that CircRNAs play a role in various diseases,especially in tumor progression,proliferation,invasion,and metastasis and immune regulation.Therefore,by elucidating the expression and roles of proteins encoded by CircRNAs in tumorigenesis and development,this paper is expected to provide new tumor markers and potential targets for tumor diagnosis and treatment.

Correction to “Genome-wide CRISPR-Cas9 screening identifies that hypoxia-inducible factor-1a-induced CBX8 transcription promotes pancreatic cancer progression via IRS1/AKT axis”

Correction to “Genome-wide CRISPR-Cas9 screening identifies that hypoxia-inducible factor-1a-induced CBX8 transcription promotes pancreatic cancer progression via IRS1/AKT axis” (PMID: 34853645 PMCID: PMC8603463 DOI: 10.4251/wjgo.v13.i11.1709). In this article, the picture of Figure 6C was misused due to our carelessness while typesetting. We corrected this mistake, and replaced the incorrect image with the correct one.

Long noncoding RNA negative regulator of antiviral response contributes to pancreatic ductal adenocarcinoma progression via targeting miR-299-3p

BACKGROUND

Pancreatic ductal cancer (PDAC) has high malignancy and poor prognosis. Long noncoding RNAs (lncRNAs) are associated with high levels of malignancy, including PDAC. However, the biological and clinical significance of negative regulator of antiviral response (NRAV) in PDAC is unclear.

AIM

To study the regulatory role of lncRNA NRAV in PDAC.

METHODS

GEPIA analyzed lncRNA NRAV and miRNA (miR-299-3p) expression levels in PDAC tissues and measured them in PDAC cells by quantitative measurements in real time. The specific role of NRAV and miR-299-3p in cell proliferation and transfer potential was evaluated by cell formation analysis, Cell Counting Kit-8 and Transwell analysis. The relationship between NRAV and miR-299-3p was studied by predictive bioinformatics, RNA immunoassay, and fluorescence enzyme analysis. In vivo experiments included transplantation of simulated tumor cells under naked mice.

RESULTS

The expression level of lncRNA NRAV was higher in both tumor tissues and cell lines of PDAC and was negatively associated with the clinical survival of PDAC patients. Functionally, overexpression of NRAV promoted cell proliferation and metastasis of PDAC cells, while knockdown of NRAV reversed these effects. Finally, NRAV was performed as a molecular sponge of miR-299-3p. Moreover, overexpression of miR-299-3p could reverse the promoting effects of NRAV on cell proliferation and metastasis of PDAC cells.

CONCLUSION

NRAV facilitates progression of PDAC as a molecular sponge of miR-299-3p and may be a potential molecular marker for diagnosis and treatment of PDAC.

Genome-wide CRISPR-Cas9 screening identifies that hypoxia-inducible factor-1a-induced CBX8 transcription promotes pancreatic cancer progression via IRS1/AKT axis

BACKGROUND

Pancreatic cancer (PC) is one of the most lethal malignancies worldwide. It is known that the proliferation of PC cells is a critical process in the disease. Previous studies have failed to identify the key genes associated with PC cell proliferation, using bioinformatic analysis, genome-wide association studies, and candidate gene testing.

AIM

To investigate the function of the chromobox 8 (CBX8)/receptor substrate 1 (IRS1)/AKT axis in PC.

METHODS

A genome-wide CRISPR-Cas9 screening was performed to select genes that could facilitate PC cell proliferation. Quantitative reverse transcription-polymerase chain reaction was used to detect the expression of CBX8 in PC tissues and cells. The regulatory roles of CBX8 in cell proliferation, migration, and invasion were verified by in vivo and in vitro functional assays.

RESULTS

CBX8 was upregulated in PC tissues and shown to drive PC cell proliferation. Higher expression of CBX8 was correlated with worse outcomes of PC patients from two independent cohorts comprising a total of 116 cases. CBX8 was also proved to serve as a promising therapeutic target for a PC xenograft model. We demonstrated that hypoxia-inducible factor (HIF)-1a induced CBX8 transcription by binding to the promoter of CBX8. CBX8 efficiently activated the PI3K/AKT signaling by upregulating insulin IRS1.

CONCLUSION

CBX8 is a key gene regulated by HIF-1α, and activates the IRS1/AKT pathway, which suggests that targeting CBX8 may be a promising therapeutic strategy for PC.

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.

Comparative study of oncologic efficacy of cephalomedial to lateral dissection versus medial to lateral dissection in laparoscopic total mesorectal excision for rectal cancer: An RCT study

BACKGROUND AND OBJECTIVES

We compared the 3-year overall survival between cephalomedial-to-lateral approach proctectomy (CEMP) and medial-to-lateral approach proctectomy (MAP) in patients undergoing laparoscopic total mesorectal excision for rectal cancer. The advantages of CEMP and the clinical value of No. 253 lymph nodes resection have not been objectively analyzed in literature.

METHODS

This was a prospective, two-arm, multicenter, single-blinded, randomized trial. The primary endpoint was 3-year overall survival, and secondary endpoints included safety, feasibility, oncological radicality (including number of No. 253 lymph nodes harvested), short-term outcome, 3-year disease-free survival, rate of postoperative complications, mortality, and rate of recurrence.

RESULTS

From May 2016 to July 2020, 506 patients were enrolled-256 in the CEMP group and 250 in the MAP group. Comparison of overall survival and disease-free survival showed that there was treatment benefit in the CEMP group (28.22 ± 12.12 vs. 27.44 ± 13.06, p = 0.485; 27.24 ± 12.01 vs. 26.42 ± 12.81; p = 0.457). More No. 253 lymph nodes were harvested in the CEMP group, and cases with positive No. 253 lymph nodes had worse prognosis in stage III. Surgical safety was equal for both approaches.

CONCLUSIONS

Dissection of No. 253 lymph nodes may be important to improve clinical prognosis, but further studies with larger samples are needed to confirm this finding.

MiR-301a transcriptionally activated by HIF-2α promotes hypoxia-induced epithelial-mesenchymal transition by targeting TP63 in pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) is one of the deadliest cancers worldwide. PC metastasis involves a complex set of events, including epithelial-mesenchymal transition (EMT), that increase tumor cell invasiveness. Recent evidence has shown that hypoxia is a major EMT regulator in pancreatic cancer cells and facilitates metastasis; however, the mechanisms remain elusive.

AIM

To investigate the role of miR-301a in hypoxia-induced EMT in PC cells.

METHODS

Real-time PCR and Western blot analysis were used to detect the expression of miR-301a and EMT markers in PDAC cells cultured in hypoxic and normoxic conditions. Western blot analysis was used to detect the expression of EMT markers in PDAC cells with miR-301a overexpression. Wound healing assay and Transwell assay were used to detect the migration capabilities of PDAC cells with miR-301a overexpression and knockout. Luciferase assay was used to detect the miR-301a promoter and the 3' untranslated region activity of TP63. Orthotopic PC mouse models were used to study the role of miR-301a in metastasis of PDAC cells in vivo. In situ hybridization assay was used to detect the expression of miR-301a in PDAC patient samples (adjacent paratumor and paired tumor tissues).  .

RESULTS

Hypoxic environment could directly promote the EMT of PC cells. The expression level of miR-301a was increased in a HIF2α dependent manner in hypoxia-cultured CFPAC-1 and BxPC-3 cells. Overexpression of miR-301a enhanced the hypoxia-induced EMT of PC cells, while knocking out miR-301a result in the suppression of hypoxia-induced EMT. TP63 was a direct target of miR-301a and involved in the metastatic process of PC cells. Furthermore, miR-301a upregulation facilitated PDAC distant metastasis and lymph node metastasis in vivo. Additionally, miR-301a overexpression was indicative of aggressive clinicopathological behaviors and poor prognosis.

CONCLUSION

The newly identified HIF-2α-miR301a-TP63 signaling pathway may play a crucial role in hypoxia-induced EMT in PDAC cells.

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.

Current research status of endoscopic submucosal dissection for colorectal neoplasms

Endoscopic submucosal dissection (ESD) has been applied to, and gradually standardized for, early gastric cancers; however, it has not yet been widely used for treatment of colorectal neoplasms. Compared with gastric ESD, the thinner colorectal wall and winding nature of the colon make colorectal ESD a much more difficult operative technique. Despite greater risks of postoperative complications, particularly perforation of the colon, more and more endoscopists are making an effort to study this new technique in terms of its capability of larger neoplastic resection, higher en bloc resection rate and lower local recurrence rate of neoplasms in comparison with other endoscopic treatments. Thus, colorectal ESD may become the standard treatment for early colorectal neoplasms in the future. This review article discusses the current research on endoscopic submucosal dissection for colorectal neoplasms.

Natural orifice transluminal endoscopic surgery: New minimally invasive surgery come of age

Although in the past two decades, laparoscopic surgery, considered as a great revolution in the minimally invasive surgery field, has undergone major development worldwide, another dramatic surgical revolution has quietly appeared in recent years. Ever since Kalloo’s first report on transgastric peritoneoscopy in a porcine model in 2004, interest in a new surgical procedure named natural orifice transluminal endoscopic surgery (NOTES) has blossomed worldwide. Considering that a NOTES procedure could theoretically avoid any abdominal incision, operation-related pain and scarring, many surgeons and endoscopists have been enthusiastic in their study of this new technique. In recent years, several NOTES studies have been carried out on porcine models and even on humans, including transvaginal cholecystectomy, transgastric appendectomy, transvaginal appendectomy, and transvesical peritoneoscopy. So what is the current situation of NOTES and how many challenges do we still face? This review discusses the current research progress in NOTES.

Clinical significance of expression of HIF-1α and EMT-related factors in pancreatic ductal adenocarcinoma

AIM: To investigate the expression of hypoxia inducible factor-1α (HIF-1α) and epithelial-mesenchvmal transition (EMT)-related factors in pancreatic ductal adenocarcinoma (PDAC) and to analyze their clinical significance.

METHODS: Immunohistochemistry was used to examine the expression of HIF-1α, Snail, Slug, E-cadherin and N-cadherin in 92 cases of PDAC and 10 cases of normal pancreatic tissue.

RESULTS: The positive expression rates of HIF-1α, Snail, Slug, E-cadherin and N-cadherin were 69.57%, 69.57%, 58.70%, 36.96% and 73.91% in PDAC, and 10%, 0%, 0%, 90% and 0% in normal pancreas tissue. HIF-1α expression was significantly associated with lymph node metastasis. Snail expression was correlated with TNM stage. Slug expression was positively associated with TNM stage and lymph node metastasis. N-cadherin expression was significantly related to TNM stage, lymph node metastasis and histological grade. HIF-1α expression in PDAC was positively correlated with Snail and Slug expression. There was a negative correlation between Snail and E-cadherin expression in PDAC. Expression of E-cadherin was negatively related to that of N-cadherin. Multivariate Cox analysis demonstrated that HIF-1α, Snail and E-cadherin were independent factors for prognosis of PDAC.

CONCLUSION: HIF-1α, Snail, Slug, E-cadherin and N-cadherin play significant roles in the progression and prognosis of PDAC.

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.

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.

Expression and prognostic significance of CD151, c-Met, and integrin alpha3/alpha6 in pancreatic ductal adenocarcinoma

BACKGROUND

CD151, c-Met, and integrin alpha3/alpha6 are all involved in the hepatocyte growth factor (HGF)/c-Met signal pathway, which plays an important role in the malignant progression of tumors.

AIMS

The purpose of this study was to explore the expression and prognostic significance of these proteins in pancreatic ductal adenocarcinoma (PDAC).

METHODS

We used immunohistochemical methods to investigate the expression patterns of CD151, c-Met, and integrin alpha3/alpha6proteins in 71 patients with PDAC and in ten samples of normal pancreatic tissue. We also assessed correlations between these proteins and clinicopathological parameters and survival of PDAC patients using various statistical methods.

RESULTS

CD151, c-Met, and integrin alpha3/alpha6 were all overexpressed in PDAC. CD151 and c-Met overexpressions were significantly associated with TNM stage (p=0.001 and p=0.038, respectively) and lymph node invasion (p=0.000, p=0.012, respectively). A significant positive linear correlation was found between CD151 and c-Met (r=0.583; p=0.000), integrin alpha3 (r=0.457; p=0.000), and integrin alpha6 (r=0.671; p=0.000). Overexpression of CD151, c-Met, integrin alpha3, or integrin alpha6 was related to poor survival of PDAC patients (p=0.000, p=0.000, p=0.005, and p=0.003, respectively), and CD151 and c-Met were independent factors in prognosis of PDAC.

CONCLUSIONS

CD151, c-Met, and integrin alpha3/alpha6 were all overexpressed in PDAC. CD151 and c-Met might be new molecular markers to predict the prognosis of PDAC patients.

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.

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.

[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.

[Study on the relationship between spectral properties of oilseed rape leaves and their chlorophyll content]

Chlorophyll is the important factors of the crop in its growth stage, and it is the favorable indicator of nutrition stress and photosynthesis. Site-specific crop nutrition diagnosis is the basics of the scientific fertilizer management, and it is essential for the practice of precision agriculture. Spectral properties of the oilseed rape leaves in different nitrogenous fertilizer levels were measured using visible-near infrared reflectance spectroscopy (Vis-NIRS) with natural illumination in the present study. According to the unique spectral properties of the crop, multiple stepwise regression technique was used to find the relationships between chlorophyll content and red edge, green edge. The result shows that the model with two independent variables (red edge, green edge) was better than with the one independeot variable (red edge). The correlation coefficient was 0.863, 0.848, and SEC was 5.273, 5.459, respectively. It can be seen the combination of the red edge and green edge can accurately predict chlorophyll content.

[Research on discrimination method of orange juice variety based on spectroscopy technology]

In order to quickly analyze varieties of orange juice with near infrared spectra, firstly, principal component analysis (PCA) was used to analysze the clustering of orange juice samples, and the characteristic differentia of four orange juice varieties was obtained through qualitative analysis. Then plentiful spectral data were compressed by wavelet transform (WT) and the model was built with radial basis function neural network (RBF-NN), which offered a quantitative analysis of orange juice varieties discrimination. The model regarded the compressed data as the input of RBF-NN input vectors and built a RBF-NN model. Two hundred forty samples from four varieties were selected randomly to build the training model, which in turn was used to predict the varieties of 60 unknown samples. The discrimination rate of 100% was achieved by WT-RBFNN method. It was indicated that wavelet transform combined with RBF-NN is an available method for variety discrimination based on the near infrared reflectance spectroscopy technology. It offered a new approach to the fast discrimination of varieties of orange juice.

Expression and correlation of Hypoxia inducible Factor 1α and drug-resistance-correlated proteins in human pancreatic carcinoma

AIM: To investigate the expression of Hypoxia inducible Factor 1α(HIF-1α) and the drug-resistance-correlated indexes P-glycoprotein (P-Gp), Bcl-X_L and Bax, and the relationship between HIF-1α and resistance to chemotherapy in human pancreatic carcinoma.

METHODS: Protein expression of HIF-1α, P-Gp, Bcl-X_L and Bax in pancreatic tissues from 34 radically resected specimens of pancreatic carcinoma was detected by immunohistochemical staining.

RESULTS: The protein expression rates of HIF-1α, P-Gp, Bcl-X_L and Bax in pancreatic carcinoma were 26/34 (76.5%), 28/34 (82.4%), 30/34 (88.2%) and 26/34 (76.5%), respectively. There were positive correlations between the positivity rates of HIF-1α and P-Gp, Bcl-X_L and Bax (r = 0.471, P = 0.005; r = 0.443, P = 0.009; r = 0.510, P = 0.002).

CONCLUSION: HIF-1α, P-Gp, Bcl-X_L and Bax were over-expressed in human pancreatic carcinoma tissues. A positive correlation was determined between the expression rates of HIF-1α and P-Gp, Bcl-X_L and Bax. HIF-1α may have a significant role in resistance to chemotherapy in pancreatic carcinoma via up-regulation of the expression of P-Gp, Bcl-X_L and Bax.

[Spectroscopic analysis of sun protection factor (SPF) of sunscreen cosmetic]

Sunscreen index is the primary indicator of the protection effect of sunscreen cosmetics. A handheld spectrometer was used to study the relationship between sunscreen index and reflectance spectra. Three kinds of Dingjiayi brand sunscreen cosmetics, which is SPF15, SPF20 and SPF30, were chosen as experimental material. The sunscreen cosmetics were divided into 75 samples, and 60 of them were used as calibrated samples, while the other 15 samples were used as prediction samples. The reflectance spectra data were collected by the spectrometer. The data from the wavelength range between 400 and 960 nm were processed by principal component analysis method, and the results showed that the cumulate reliabilities of PC1 and PC2 (the first two principal components) reached 91%. Then partial least square analysis method was applied to build prediction models, and the remaining 15 prediction samples were disposed by this model. The results show that the prediction correlation coefficient is 0.967 7, and the prediction precision is good. So the spectral analysis method proposed in the present paper has good performance in classification and discrimination of sunscreen cosmetics, and is a new approach to test the SPF of cosmetics.

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.

Effect of AG490 combined with gemcitabine on the growth of human pancreatic cancer cells

AIM: To investigate the effect of Janus kinase (JAK) specific inhibitor AG490 combined with gemcitabine on the proliferation of human pancreatic cancer cell line SW1990 and STAT3 signal transduction pathway as well as their mechanisms.

METHODS: Human pancreatic cancer cell line SW1990 was divided into control group, AG490-treated group, gemcitabine-treated group and AG490 + gemcitabine-treated group. After 48 h, the proliferation of SW1990 cells was detected by MTT assay. Flow cytometry was used to examine cell apoptosis. The expression of STAT3, Cyclin D1, Bcl-xL and Bax were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, respectively.

RESULTS: The proliferation of SW1990 cells was significantly lower in AG490 or gemcitabine group than that in control group (2.20 ± 0.25, 2.30 ± 0.220 vs 3.78 ± 0.42, P < 0.05), but the apoptosis rate was markedly higher (35.40% ± 3.08%, 34.64% ± 1.38% vs 16.49% ± 1.45%, P < 0.05). Moreover, the proliferation (1.49 ± 0.15) and apoptosis (43.80% ± 1.57%) had notable difference between AG490+gemcitabine group and AG490 or gemcitabine group. After 48 h, AG490 remarkably down-regulated the expression of p-STAT3 (13.83% ± 0.64% vs 79.87% ± 1.43%, P < 0.05), and the expression of Cyclin D1 (mRNA: 15.63% ± 0.59% vs 43.83% ± 0.64%, P < 0.05; protein: 17.50% ± 0.92% 49.87% ± 1.27%, P < 0.05), Bcl-xL (mRNA: 13.93% ± 0.21% vs 75.70% ± 0.46%, P < 0.05; protein: 34.17% ± 1.70% vs 83.93% ± 0.80%, P < 0.05) and Survivin (mRNA: 58.27% ± 0.42% vs 82.93% ± 1.68%, P < 0.05; protein: 13.23% ± 1.03% vs 18.60 ± 1.08%, P < 0.05) were also decreased in comparison with that in control group; however, Bax expression was increased (mRNA: 10.33% ± 1.18% vs 5.43% ± 0.70%, P < 0.05; protein: 13.07% ± 1.04% vs 6.23% ± 2.40%, P < 0.05). There was no difference between gemcitabine and control group.

CONCLUSION: Blockade of STAT3 signal pathway inhibits the proliferation and promotes the apoptosis of SW1990 cells. AG490 combined with gemcitabine shows a synergic effect, which provides a new therapeutic approach for pancreatic cancer therapy.

Expression of p-STAT3 and E-cadherin in pancreatic cancer and their clinical significances

AIM: To investigate the expression of phospho-rylated signal transduction and activators of transcription-3 (p-STAT3) and E-cadherin as well as their correlations with the clinicopathological parameters in pancreatic cancer, and to reveal the role of STAT3 signal pathway in the invasion and metastasis of pancreatic cancer.

METHODS: Immunohistochemistry was used to detect the expression of p-STAT3 and E-cadherin in 34 cases of pancreatic cancer and 10 cases of normal pancreatic tissues. Cell invasion assay kit was used to examine the invasion ability of pancreatic cancer cells SW1990 and CaPan-2. Western blot and electrophoretic mobility shift assay (EMSA) were applied to detect the protein expression of p-STAT3 and STAT3 DNA-binding activity in SW1990 and CaPan-2 cells.

RESULTS: Immunohistochemistry revealed high expression of p-STAT3 (64.7%) but low expression of E-cadherin in pancreatic cancer. The expression of p-STAT3 was significantly correlated with the clinical stages (P = 0.017) and lymph node metastasis (P = 0.013), and the expression of E-cadherin was correlated with the pathological degrees (P = 0.002), clinical stages (P = 0.034) and lymph node metastasis (P = 0.019). There was a negative correlation between p-STAT3 and E-cadherin expression in pancreatic cancer (r = -0.537, P = 0.001). Cell invasion assay indicated a more invasive ability in SW1990 cells than that in CaPan-2 cells (P < 0.05). Finally, Western blot and EMSA showed that p-STAT3 protein level and STAT3 DNA-binding activity were significantly higher in SW1990 cells as compared with those in CaPan-2 cells (P < 0.05).

CONCLUSION: The expression of p-STAT3 is closely related to the invasion and metastasis of pancreatic cancer and abnormal expression of E-cadherin. The combined detection for these two proteins may be useful in determining of the metastasis potency of pancreatic cancer.

[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.

[Portal venous and enteric drainage in simultaneous pancreas kidney transplantation]

OBJECTIVE

To summarize the initial experience of simultaneous pancreas kidney transplantation (SPK) with portal venous and enteric drainage.

METHODS

Between Jane 2001 and Jane 2003, SPK were performed in 5 patients. Systemic venous-enteric drainage (SED) was used in the first 2 patients and portal venous-enteric drainage (PED) in the last 3 cases. All patient were immunosuppressed with quadruple therapy, which included anti-CD25 mAb (Zenapax/Simulect) induction therapy, FK506, mycophenolate mofetil (MMF), and prednisone baseline therapy. The complications were analyzed.

RESULTS

Serum glucose and renal function of the 5 cases were normal and no further insulin was needed within 7 days post-operation. No technique complications such as duodenal fistula and thrombosis were observed, One episode of acute rejection of kidney allograft occurred in one patient with SED, and resolved with a bolus corticosteroids. One case with SED and one with PED were died of sepsis and FK506 toxicity 4 weeks after transplantation. The death occurred with functioning pancreas graft. No latter complications were observed in the 3 survived patients with excellent graft functions.

CONCLUSIONS

Both methods of SED and PED can be performed successfully and with no latter complications. But with its potential physiologic and immunologic advantages, PED might be a standard procedure for SPK.

[An immunocytochemical study of neuropeptide-like in a ciliated protozoan, Stylonychia mytilus]

An immunocytochemical investigation with both B-SA and ABC methods, under LM and EM, was carried out on Stylonychia mytilus by using 7 antisera to vertebrate neuropeptides, hormones and TH. The immunotests showed the presence of substance p-, neuropeptide y-, cck-8-, somatostatin-, beta-endorphin, adrenocorticotropic hormone-, and TH-like immunoreactive molecules in Stylonychia mytilus. The distributions of these immunoreactive substances in Stylonychia mytilus were described.

[Long-term results of patients with positive margin after resection of esophageal and gastric cardiac cancers]

From April 1964 to December 1982, 1168 cases with esophageal and cardiac carcinoma underwent esophagogastrectomy. One hundred and fifty-five (13.3%) cases were found to have residual tumor at the esophagogastric stump under microscope. Among them (74 esophageal carcinoma and 81 cardiac carcinoma), 1 died of pneumonia on day 15 after operation and 1 was lost from follow-up. The remaining 153 cases were followed for over 5 years. The 1, 3 and 5 year survival rates were 70.3%, 34.8% and 26.5%, respectively. The main factors influencing the survival were histological classification, depth of tumor infiltration, lymph node metastasis and radical or conservative resection. Long term survival of these patients may be associated with their immunological status.

Morphology and development of left-handed singlets derived from mirror-image doublets of Stylonychia mytilus

Mirror-image doublets of Stylonychia mytilus include 2 sets of cortical structures, one with the normal "right-handed" (RH) arrangement, the other with a reversed "left-handed" (LH) arrangement. These sets, however, are incomplete, with certain structures, most notably cirri of the right marginal type, missing near the line of symmetry. When a mirror-image doublet is bisected longitudinally to separate the RH and LH components physically, each fragment undergoes a regeneration process that restores a complete set of cortical structures, including the previously missing cirri of the right marginal type. In the resulting LH cell, all ciliary structures are present in an arrangement that is globally reversed in relation to that found in RH cells; in particular, marginal cirri of the left-marginal type are formed at the cell's right margin, and marginal cirri of the right-marginal type are produced at the cell's left margin. Whereas the regenerated RH fragment always divides and initiates a clone of normal singlets, the LH fragment, though structurally nearly complete, in all cases eventually dies without dividing. The cause of death is starvation due to the formation of an abnormal oral apparatus. In the Discussion, we consider the nature and consequences of a reversal of global positional information.