Distinct expression levels and patterns of stem cell marker, aldehyde dehydrogenase isoform 1 (ALDH1), in human epithelial cancers

Aldehyde dehydrogenase isoform 1 (ALDH1) has been proved useful for the identification of cancer stem cells. However, our knowledge of the expression and activity of ALDH1 in common epithelial cancers and their corresponding normal tissues is still largely absent. Therefore, we characterized ALDH1 expression in 24 types of normal tissues and a large collection of epithelial tumor specimens (six cancer types, n = 792) by immunohistochemical staining. Using the ALDEFUOR assay, ALDH1 activity was also examined in 16 primary tumor specimens and 43 established epithelial cancer cell lines. In addition, an ovarian cancer transgenic mouse model and 7 murine ovarian cancer cell lines were analyzed. We found that the expression levels and patterns of ALDH1 in epithelial cancers are remarkably distinct, and they correlate with their corresponding normal tissues. ALDH1 protein expression levels are positively correlated with ALDH1 enzymatic activity measured by ALDEFLUOR assay. Long-term in vitro culture doesn't significantly affect ALDH1 activity in epithelial tumor cells. Consistent with research on other cancers, we found that high ALDH1 expression is significantly associated with poor clinical outcomes in serous ovarian cancer patients (n = 439, p = 0.0036). Finally, ALDH^br tumor cells exhibit cancer stem cell properties and are resistant to chemotherapy. As a novel cancer stem cell marker, ALDH1 can be used for tumors whose corresponding normal tissues express ALDH1 in relatively restricted or limited levels such as breast, lung, ovarian or colon cancer.

Double-negative feedback loop between reprogramming factor LIN28 and microRNA let-7 regulates aldehyde dehydrogenase 1-positive cancer stem cells

A relatively rare aldehyde dehydrogenase 1 (ALDH1)-positive "stem cell-like" subpopulation of tumor cells has the unique ability to initiate and perpetuate tumor growth; moreover, it is highly resistant to chemotherapy and significantly associated with poor clinical outcomes. The development of more effective therapies for cancer requires targeting of this cell population. Using cDNA microarray analysis, we identified that the expression of the Caenorhabditis elegans lin-28 homologue (LIN28) was positively correlated with the percentage of ALDH1+ tumor cells; this was further validated in an independent set of tissue arrays (n=197). Both loss-of-function and gain-of-function studies showed that LIN28 plays a critical role in the maintenance of ALDH1+ tumor cells. In addition, we found that there is a double-negative feedback loop between LIN28 and let-7 in tumor cells, and that let-7 negatively regulates ALDH1+ tumor cells. Finally, we report that a LIN28/let-7 loop modulates self-renewal and differentiation of mammary gland epithelial progenitor cells. Our data provide evidence that cancer stem cells may arise through a "reprogramming-like" mechanism. A rebalancing of the LIN28/let-7 regulatory loop could be a novel therapeutic strategy to target ALDH1+ cancer stem cells.

mir-30d Regulates multiple genes in the autophagy pathway and impairs autophagy process in human cancer cells

In human epithelial cancers, the microRNA (miRNA) mir-30d is amplified with high frequency and serves as a critical oncomir by regulating metastasis, apoptosis, proliferation, and differentiation. Autophagy, a degradation pathway for long-lived protein and organelles, regulates the survival and death of many cell types. Increasing evidence suggests that autophagy plays an important function in epithelial tumor initiation and progression. Using a combined bioinformatics approach, gene set enrichment analysis, and miRNA target prediction, we found that mir-30d might regulate multiple genes in the autophagy pathway including BECN1, BNIP3L, ATG12, ATG5, and ATG2. Our further functional experiments demonstrated that the expression of these core proteins in the autophagy pathway was directly suppressed by mir-30d in cancer cells. Finally, we showed that mir-30d regulated the autophagy process by inhibiting autophagosome formation and LC3B-I conversion to LC3B-II. Taken together, our results provide evidence that the oncomir mir-30d impairs the autophagy process by targeting multiple genes in the autophagy pathway. This result will contribute to understanding the molecular mechanism of mir-30d in tumorigenesis and developing novel cancer therapy strategy.

Silencing alpha-fetoprotein expression induces growth arrest and apoptosis in human hepatocellular cancer cell

The expression of alpha-fetoprotein (AFP), a tumor-associated antigen, is silenced in normal adult hepatocyte but reactivated in human hepatocellular carcinoma (HCC). To investigate the roles of AFP in the regulation of cell growth, we silenced AFP expression in the HCC cell line Huh7 by transfection of specific Stealth RNAi. After the transfection for 48 h, the expression of AFP gene was almost abolished, the cell proliferation was inhibited by 46.15%, and the number of cells undergoing early apoptosis was significantly increased to 63.93%. Inhibition of AFP expression also resulted in an increased in Bax/Bcl-2 ratio, the release of cytochrome c from mitochondria and activation of caspase-3. The results suggest that AFP may positively regulate cell proliferation by enhancing the apoptosis resistance via dysfunction of the p53/Bax/cytochrome c/caspase-3 signaling pathway in AFP-producing HCC cell line. As such, the knockdown of AFP gene should be further investigated in vivo as a novel approach to HCC treatment.

Genomic DNA copy-number alterations of the let-7 family in human cancers

In human cancer, expression of the let-7 family is significantly reduced, and this is associated with shorter survival times in patients. However, the mechanisms leading to let-7 downregulation in cancer are still largely unclear. Since an alteration in copy-number is one of the causes of gene deregulation in cancer, we examined copy number alterations of the let-7 family in 2,969 cancer specimens from a high-resolution SNP array dataset. We found that there was a reduction in the copy number of let-7 genes in a cancer-type specific manner. Importantly, focal deletion of four let-7 family members was found in three cancer types: medulloblastoma (let-7a-2 and let-7e), breast cancer (let-7a-2), and ovarian cancer (let-7a-3/let-7b). For example, the genomic locus harboring let-7a-3/let-7b was deleted in 44% of the specimens from ovarian cancer patients. We also found a positive correlation between the copy number of let-7b and mature let-7b expression in ovarian cancer. Finally, we showed that restoration of let-7b expression dramatically reduced ovarian tumor growth in vitro and in vivo. Our results indicate that copy number deletion is an important mechanism leading to the downregulation of expression of specific let-7 family members in medulloblastoma, breast, and ovarian cancers. Restoration of let-7 expression in tumor cells could provide a novel therapeutic strategy for the treatment of cancer.

Inhibition of c-Myc by let-7b mimic reverses mutidrug resistance in gastric cancer cells

Chemotherapy is one of the few effective choices for patients with advanced or recurrent gastric cancer (GC). However, the development of mutidrug resistance (MDR) to cancer chemotherapy is a major obstacle to the effective treatment of advanced GC. Additionally, the mechanism of MDR remains to be determined. In the present study, we tested IC50 of cisplatin (DDP), vincristine (VCR) and 5-fluorouracil (5-FU) in SGC7901, SGC7901/DDP and SGC7901/VCR gastric cancer cells using an MTT assay. The expression of let-7b and c-Myc in these cells was detected by qPCR and western blot analysis. The relationship between let-7b and c-Myc was explored using a luciferase reporter assay. Transfection of let-7b mimic or inhibitor was used to confirm the effect of let-7b on drug sensitivity in chemotherapy via the regulation of c-Myc expression. We found that the expression of let-7b was lower in chemotherapy-resistant SGC7901/DDP and SGC7901/VCR gastric cancer cells than that in chemotherapy-sensitive SGC7901 cells. By contrast, the expression of c-Myc was higher in SGC7901/DDP and SGC7901/VCR cells than that in SGC7901 cells. Furthermore, we confirmed that let-7b suppresses c-Myc gene expression at the mRNA and protein levels in a sequence-specific manner, while transfection of let-7b mimic increases drug sensitivity in chemotherapy-resistant SGC7901/DDP and SGC7901/VCR cells by targeting downregulation of c-Myc. In SGC7901 drug-sensitive cells, however, the sensitivity of chemotherapy was significantly decreased following let-7b inhibitor transfection. The present study results demonstrated that let-7b increases drug sensitivity in chemotherapy‑resistant SGC7901/DDP and SGC7901/VCR gastric cancer cells by targeting the downregulation of c-Myc and that, let-7b mimic reverses MDR by promoting cancer stem cell differentiation controlled by double-negative autoregulatory loops (Lin28/let-7 and Myc/let-7) and a double-positive autoregulatory loop (Lin28/Lin28B/Myc) existing in GC cells, which remains to be confirmed.

Lupeol, a dietary triterpene, inhibited growth, and induced apoptosis through down-regulation of DR3 in SMMC7721 cells

Lupeol (Lup-20(29)-en-3H-ol), a novel dietary triterpene, was found in fruits, vegetables, and several medicinal plants. Here, we investigated its growth-inhibitory effect and associated mechanisms in hepatocellular carcinoma SMMC7721 cells. Lupeol treatment resulted in significant inhibition of cell viability in a dose-dependent manner and caused apoptotic death of this cell line with activation of caspase3 expression. Caspase8 inhibitor pretreatment was found to partially block the apoptosis induced by Lupeol. Moreover, Lupeol specifically caused a significant decrease in the expression of Death receptor 3 (DR3) mRNA and protein and a significant elevated expression of FADD mRNA whereas Fas mRNA and protein expression was not detectable. Further more, knockdown of DR3 by small interfering RNA inhibited the growth and induced apoptosis of hepatocellular carcinoma cell. These results suggested that Lupeol treatment induced growth inhibition and apoptosis in SMMC7721 cells, the mechanism is due to down-regulation of DR3 expression. We demonstrated that Lupeol appears to be a promising chemopreventive agent for treating hepatocellular carcinoma, and DR3 may be an important target for liver cancer therapy.

Mir-30d increases intracellular survival of Helicobacter pylori through inhibition of autophagy pathway

AIM

To determine if mir-30d inhibits the autophagy response to Helicobacter pylori (H. pylori) invasion and increases H. pylori intracellular survival.

METHODS

The expression of mir-30d was detected by quantitative polymerase chain reaction (PCR), and autophagy level was examined by transmission electron microscopy, western blot, and GFP-LC3 puncta assay in human AGS cells and GES-1 cells. Luciferase reporter assay was applied to confirm the specificity of mir-30d regulation on the expression of several core molecules involved in autophagy pathway. The expression of multiple core proteins were analyzed at both the mRNA and protein level, and the intracellular survival of H. pylori after different treatments was detected by gentamicin protection assay.

RESULTS

Autophagy level was increased in AGS and GES-1 cells in response to H. pylori infection, which was accompanied by upregulation of mir-30d expression (P < 0.05, vs no H. pylori infection). In the two gastric epithelial cell lines, mimic mir-30d was found to repress the autophagy process, whereas mir-30d inhibitor increased autophagy response to H. pylori invasion. mir-30d mimic decreased the luciferase activity of wild type reporter plasmids carrying the 3' untranslated region (UTR) of all five tested genes (ATG2B, ATG5, ATG12, BECN1, and BNIP3L), whereas it had no effect on the mutant reporter plasmids. These five genes are core genes of autophagy pathway, and their expression was reduced significantly after mir-30d mimic transfection (P < 0.05, vs control cells without mir-30d mimic treatment). Mir-30d mimic transfection and direct inhibition of autophagy increased the intracellular survival of H. pylori in AGS cells.

CONCLUSION

Mir-30d increases intracellular survival of H. pylori in gastric epithelial cells through inhibition of multiple core proteins in the autophagy pathway.

Let7b modulates the Wnt/β-catenin pathway in liver cancer cells via downregulated Frizzled4

Let7 microRNA implicated in many cellular processes and participated in the progress of various tumors. Similarly, Wnt signaling pathway plays an important role in morphogenesis, differentiation, cell survival, and proliferation. However, there is little research focusing on the relevance between Let7b and Wnt/β-catenin signaling pathway, especially in liver cancer cell. To study this, human liver cancer cells HUH7 and MHCC97H were cultured, enhanced, or inhibited the expression of Let7b in two cell lines. Western blotting was used to measure the expression of Wnt signaling-related protein β-catenin and Frizzled family receptor. CD24⁺133⁺ was used as a cancer stem cell marker, and the proportion of CD24⁺133⁺ in liver cancer cell lines was observed by flow cytometry. The proliferation, invasiveness, and migration of liver cancer cells were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, transwell, and wound healing assays. The research revealed that enhanced expression of Let7b decreased the expression of Frizzled4, while inhibited Let7b expression increased Frizzled4 expression. Enhanced Let7b expression reduced the proportion of cancer stem cell in liver cancer cell; meanwhile, Let7b inhibition increased the proportion of cancer stem cell. Upregulated Let7b expression repressed the proliferation, invasion, and migration of liver cancer cell. This study showed that Let7b modulates the proliferation, invasiveness, and migration of liver cancer cell and reduces the proportion of cancer stem cells in liver cancer cell by inhibiting Wnt/β-catenin signaling pathway via downregulated Frizzled4.

Effect of postoperative early enteral nutrition on clinical outcomes and immune function of cholangiocarcinoma patients with malignant obstructive jaundice

BACKGROUND

Most cholangiocarcinoma patients with malignant obstructive jaundice (MOJ) have varying degrees of malnutrition and immunodeficiency preoperatively. Therefore, perioperative nutritional support has important clinical significance in the treatment of cholangiocarcinoma.

AIM

To investigate the effects of postoperative early enteral nutrition (EEN) on immunity function and clinical outcomes of cholangiocarcinoma patients with MOJ.

METHODS

This prospective clinical study included 60 cholangiocarcinoma patients with MOJ who underwent surgery. The patients were randomly divided into an experimental group and a control group according to the nutrition support modes. The control group received postoperative total parenteral nutrition (TPN), whereas the experimental group received postoperative EEN and parenteral nutrition (PN; EEN + PN). The clinical outcomes, postoperative immune function, incidences of surgical site infection and bile leakage, intestinal function recovery time, average hospitalization days, and hospitalization expenses of the two groups were assessed on postoperative days (PODs) 1, 3, and 7.

RESULTS

The CD3+T, CD4+T, CD8+T, and CD4+T/CD8+T cell count and the immunoglobulin (Ig) G, IgM, and IgA levels in the EEN + PN group were significantly higher than those in the TPN group on PODs 3 and 7 (P < 0.05), whereas no significant differences in the CD3+T, CD4+T, CD8+T, and CD4+T/CD8+T cell counts and IgG, IgM, and IgA levels before operation and on POD 1 were found between the two groups (P > 0.05). The intestinal function recovery time and postoperative hospital stay were shorter (P < 0.001 for both) in the EEN + PN group than in the TPN group. The hospitalization expenses of the EEN + PN group were lower than those of the TPN group (P < 0.001). However, the incidence of abdominal distension was higher than in the EEN + PN group than in the TPN group (P < 0.05). The incidence rates of biliary leakage and surgical site infection were not significantly different between the two groups (P > 0.05).

CONCLUSION

A postoperative EEN program could reduce the incidence of postoperative complications and improve the clinical outcomes and immune functions of cholangiocarcinoma patients with MOJ and is thus beneficial to patient recovery.

Knockdown of alpha-fetoprotein expression inhibits HepG2 cell growth and induces apoptosis

Aims

To explore the biological roles of alpha-fetoprotein (AFP), a tumor-associated antigen in human hepatocellular carcinoma (HCC).

Materials and Methods

After knockdown of AFP in HepG2 cells by transfection of specific Stealth™ RNAi, the expression of AFP were detected by reverse transcription polymerase chain reaction at mRNA level and by enzyme-linked immunosorbent assay at the protein level. Then, the effect of silenced AFP on cell proliferation was assessed by dimethylthiazolyl-2,5-diphenyl-tetrazolium bromide assay, and apoptosis assessment with Hoechst33258 and flow cytometry (double stain with fluorescein isothiocyanate/propidium iodide), the roles of AFP in the cell cycle regulation were assessed by flow cytometry. We also detected the expression of some key proteins related to apoptosis pathway by Western immunoblot analysis.

Results

After the transfection for 48 h, the expression of AFP gene was almost abolished, the cell proliferation was inhibited by 47.61%, the number of cells undergoing early apoptosis was significantly increased to 59.47%; cell cycle was arrested with the increase of G0/G1 phase cells from 45.3% to 58.4%. Inhibition of AFP expression also results in decreasing of transforming growth factor-β (TGF-β), mutant P53 expression, and increasing of Bax/Bcl-2 ratio, activation of caspase-3.

Conclusions

The results suggest that AFP may positively regulate cell proliferation by enhancing the apoptosis resistance via effect on TGF-β and p53/Bax/caspase-3 signaling pathway in HepG2 cells. As such, the knockdown of AFP gene should be further investigated in vivo as a novel approach to HCC treatment.

Increased KIF21B expression is a potential prognostic biomarker in hepatocellular carcinoma

BACKGROUND

The kinesin superfamily protein member KIF21B plays an important role in regulating mitotic progression; however, the function and mechanisms of KIF21B in cancer, particularly in hepatocellular carcinoma (HCC), are unknown.

AIM

To explore the role of KIF21B in hepatocellular carcinoma and its effect on prognosis after hepatectomy.

METHODS

First, data on the differential expression of KIF21B in patients with HCC from The Cancer Genome Atlas database was analyzed. Subsequently, the expression levels of KIF21B in HCC cell lines and hepatocytes were detected by reverse transcription-polymerase chain reaction, and its biological effect on BEL-7404 cells was evaluated by KIF21B knockdown. Immunohistochemical analysis was used to validate the differential expression of KIF21B in HCC tissues and adjacent normal tissues from 186 patients with HCC after hepatectomy. The Kaplan-Meier method was used to assess prognosis significance.

RESULTS

KIF21B expression levels were significantly higher in HCC tissues than in corresponding adjacent normal tissues. The expression levels of KIF21B in four HCC cell lines were higher than that in normal liver cells. Functional experiments showed that KIF21B knockdown remarkably suppressed cell proliferation and induced apoptosis. Moreover, immunohistochemistry results are consistent with The Cancer Genome Atlas analysis, with KIF21B expression levels being increased in HCC tissues compared to adjacent normal tissues. Univariate and multivariate analyses revealed KIF21B as an independent risk factor for overall survival and disease-free survival in patients with HCC after hepatectomy.

CONCLUSION

Taken together, our results provide evidence that KIF21B plays an important role in HCC progression and may be a potential diagnostic and prognostic marker for HCC.

Clinicopathological significance of c-MYC in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma is one of the most common malignant tumors. The oncogene c-MYC is thought to be important in the initiation, promotion, and therapy resistance of cancer. In this study, we aim to investigate the clinicopathologic roles of c-MYC in esophageal squamous cell carcinoma tissue. This study is aimed at discovering and analyzing c-MYC expression in a series of human esophageal tissues. A total of 95 esophageal squamous cell carcinoma samples were analyzed by the western blotting and immunohistochemistry techniques. Then, correlation of c-MYC expression with clinicopathological features of esophageal squamous cell carcinoma patients was statistically analyzed. In most esophageal squamous cell carcinoma cases, the c-MYC expression was positive in tumor tissues. The positive rate of c-MYC expression in tumor tissues was 61.05%, obviously higher than the adjacent normal tissues (8.42%, 8/92) and atypical hyperplasia tissues (19.75%, 16/95). There was a statistical difference among adjacent normal tissues, atypical hyperplasia tissues, and tumor tissues. Overexpression of the c-MYC was detected in 61.05% (58/95) esophageal squamous cell carcinomas, which was significantly correlated with the degree of differentiation (p = 0.004). The positive rate of c-MYC expression was 40.0% in well-differentiated esophageal tissues, with a significantly statistical difference (p = 0.004). The positive rate of c-MYC was 41.5% in T1 + T2 esophageal tissues and 74.1% in T3 + T4 esophageal tissues, with a significantly statistical difference (p = 0.001). The positive rate of c-MYC was 45.0% in I + II esophageal tissues and 72.2% in III + IV esophageal tissues, with a significantly statistical difference (p = 0.011). The c-MYC expression strongly correlated with clinical staging (p = 0.011), differentiation degree (p = 0.004), lymph node metastasis (p = 0.003), and invasion depth (p = 0.001) of patients with esophageal squamous cell carcinoma. The c-MYC was differentially expressed in a series of human esophageal tissues, and the aberrant c-MYC expression could be a potential factor in carcinogenesis and progression of esophageal squamous cell carcinoma. There was a statistical signification for c-MYC in esophageal squamous cell carcinoma patients to analyze clinicopathological features. It possibly becomes a new diagnostic indicator of esophageal squamous cell carcinoma.

Novel Models Predict Postsurgical Recurrence and Overall Survival for Patients with Hepatitis B Virus-Related Solitary Hepatocellular Carcinoma ≤10 cm and Without Portal Venous Tumor Thrombus

BACKGROUND

The predictive model of postsurgical recurrence for solitary early hepatocellular carcinoma (SE-HCC) is not well established. The aim of this study was to develop a novel model for prediction of postsurgical recurrence and survival for patients with hepatitis B virus (HBV)-related SE-HCC ≤10 cm.

PATIENTS AND METHODS

Data from 1,081 patients with HBV-related SE-HCC ≤10 cm who underwent curative liver resection from 2003 to 2016 in our center were collected retrospectively and randomly divided into the derivation cohort (n = 811) and the internal validation cohort (n = 270). Eight hundred twenty-three patients selected from another four tertiary hospitals served as the external validation cohort. Postsurgical recurrence-free survival (RFS) and overall survival (OS) predictive nomograms were generated. The discriminatory accuracies of the nomograms were compared with six conventional hepatocellular carcinoma (HCC) staging systems.

RESULTS

Tumor size, differentiation, microscopic vascular invasion, preoperative α-fetoprotein, neutrophil-to-lymphocyte ratio, albumin-to-bilirubin ratio, and blood transfusion were identified as the risk factors associated with RFS and OS. RFS and OS predictive nomograms based on these seven variables were generated. The C-index was 0.83 (95% confidence interval [CI], 0.79-0.87) for the RFS-nomogram and 0.87 (95% CI, 0.83-0.91) for the OS-nomogram. Calibration curves showed good agreement between actual observation and nomogram prediction. Both C-indices of the two nomograms were substantially higher than those of the six conventional HCC staging systems (0.54-0.74 for RFS; 0.58-0.76 for OS) and those of HCC nomograms reported in literature.

CONCLUSION

The novel nomograms were shown to be accurate at predicting postoperative recurrence and OS for patients with HBV-related SE-HCC ≤10 cm after curative liver resection.

IMPLICATIONS FOR PRACTICE

This multicenter study proposed recurrence or mortality predictive nomograms for patients with hepatitis B virus-related solitary early hepatocellular carcinoma ≤10 cm after curative liver resection. A close postsurgical surveillance protocol and adjuvant therapy should be considered for patients at high risk of recurrence.

Application of multiple Roux-en-Y hepaticojejunostomy reconstruction by formation of bile hilar duct lake in the operation of hilar cholangiocarcinoma

BACKGROUND

Hilar cholangiocarcinoma is the most common malignant tumor of the extrahepatic bile duct. Until now, radical resection has been the most effective method for the long-term survival of patients with the disease. However, many problems have emerged in the field of hepatobiliary surgery for a long time, including complex surgical procedures, low resection rate, and postoperative complications. We have adopted the "multiple Roux-en-Y hepaticojejunostomy reconstruction by formation of a bile duct lake" technique in the treatment of hilar cholangiocarcinoma since 2008, and obtained satisfactory short- and long-term results.

AIM

To examine the feasibility of the application of multiple Roux-en-Y hepaticojejunostomy reconstruction by formation of a bile duct lake in the operation of hilar cholangiocarcinoma.

METHODS

A retrospective analysis was performed for the clinical data, surgical methods, and results of 76 patients with hilar cholangiocarcinoma who were treated with hilar bile duct lake-forming multiple Roux-en-Y hepaticojejunostomy reconstruction at Gansu Provincial Hospital.

RESULTS

In all 76 cases, the operation was successful and no operative death occurred. The mean (range) operation time was 215.4 ± 53.5 min (124-678 min), and the amount of bleeding during the operation was 428.2 ± 63.8 mL (240-2200 mL). The overall 1-year survival rate was 78.9%, and the 3-year survival rate was 32.8%.

CONCLUSION

The multiple Roux-en-Y hepaticojejunostomy reconstruction technique with formation of a bile duct lake is safe and effective for the surgical treatment of hilar cholangiocarcinoma.

Long non-coding RNA small nucleolar RNA host genes: functions and mechanisms in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors of the digestive system, with a high degree of malignancy. Although treatment methods are constantly improving, the mortality of patients is still very high, and the small nucleolar RNA host gene (SNHG) plays an important role in the occurrence and development of cancer. It can activate downstream signaling molecules by acting on microRNA and microRNA target genes, promote the proliferation, invasion, and migration of HCC cells, and provide a new molecular target for the treatment of HCC. At present, the molecular mechanisms of HCC remain unclear. In this study, the mechanism and signaling pathway of SNHG in HCC are reviewed, which provides a theoretical basis for the clinical treatment of HCC.

Pancreatic outflow tract reconstruction after pancreaticoduodenectomy: a meta-analysis of randomized controlled trials

BACKGROUND

To evaluate the outcomes of pancreaticogastrostomy and pancreaticojejunostomy after pancreatoduodenectomy with the help of a meta-analysis.

METHODS

Randomized controlled trials comparing pancreaticogastrostomy and pancreaticojejunostomy were searched electronically using PubMed, The Cochrane Library, and EMBASE. Fixed and random-effects were used to measure pooled estimates. Research indicators included pancreatic fistula, delayed gastric emptying, postoperative hemorrhage, intraperitoneal fluid collection, wound infection, overall postoperative complications, reoperation, and mortality.

RESULTS

Overall, 10 randomized controlled trials were included in this meta-analysis, with a total of 1629 patients. The overall incidences of pancreatic fistula and intra-abdominal collections were lower in the pancreaticogastrostomy group than in the pancreaticojejunostomy group (OR=0.73, 95% CI 0.55~0.96, p=0.02; OR=0.59, 95% CI 0.37~0.96, p=0.02, respectively). The incidence of B/C grade pancreatic fistula in the pancreaticogastrostomy group was lower than that in the pancreaticojejunostomy group, but no significant difference was observed (OR=0.61, 95%CI 0.34~1.09, p=0.09). Postoperative hemorrhage was more frequent in the pancreaticogastrostomy group than in the pancreaticojejunostomy group (OR=1.52; 95% CI 1.08~2.14, p=0.02). No significant differences in terms of delayed gastric emptying, wound infection, reoperation, overall postoperative complications, mortality, exocrine function, and hospital readmission were observed between groups.

CONCLUSION

This meta-analysis suggests that pancreaticogastrostomy reduces the incidence of postoperative pancreatic fistula and intraperitoneal fluid collection but increases the risk of postoperative hemorrhage compared with pancreaticojejunostomy.

Safety and effectiveness of the da Vinci robot with the "3+2" mode for distal pancreatectomy

BACKGROUND

Recently, no relevant research has focused on the relationship between the clinical efficacy of da Vinci robotic distal pancreatectomy (RDP) and the number of mechanical arms and assistants used for RDP. The aim of this study was to evaluate the safety, efficacy, and advantages of RDP with the "3 + 2" mode.

METHODS

Clinical data from 53 patients (observation group) who received RDP using the "3 + 2" mode in our department, from March 2016 to September 2018, were reviewed. An additional 53 patients who received RDP using the classical mode were chosen at random for the control group. Short-term outcomes for the two groups were compared.

RESULTS

There were no statistically significant differences between the two groups for estimated blood loss, postoperative day of flatus passage, postoperative hospital stay, and postoperative complication (P > 0.05). Compared with the control group, the observation group had a significantly shorter operative time (166.9 ± 13.3 vs 192.6 ± 11.1 minutes, P < 0.001), lower surgical costs ($2827.79 ± $173.02 vs $3900.63 ± $317.29, P < 0.001).

CONCLUSIONS

The RDP using the "3 + 2" mode can increase the exposure of surgical field, improve cooperation between assistants, lower the surgical costs, and shorten the operative time and learning curve. Moreover, the clinical effect is equal to that of RDP using the classical mode. These findings indicate that RDP using the "3 + 2" mode is safe and feasible for institutions that are equipped for robot-assisted surgery.

Liposome-mediated induction of apoptosis of human hepatoma cells by c-myc antisense phosphorothioate oligodeoxynucleotide and 5-fluorouracil

BACKGROUND

The aim of this study was to investigate the effect of a c-myc antisense oligodeoxynucleotide and 5-fluorouracil on the expression of c-myc, invasion and proliferation of HEPG-2 liver cancer cells.

MATERIALS AND METHODS

HEPG-2 cells were treated with lipiosome-mediated c-myc ADSON and 5-fluorouracil. The proliferation inhibition rate and invasion were measured by MTT and invasion assay, respectively. Cell apoptosis was detected by flow cytometry and expression of c-myc by RT-PCR and immunohistochemistry.

RESULTS

The proliferation inhibition rate was significantly higher in the antisense oligodeoxynucleotide added-5-fluorouracil group than single antisense oligodeoxynucleotide or 5-fluorouracil group (p<0.05). G0/G1 cells in the antisense oligodeoxynucleotide group and S cells in the 5-fluorouracil groups were significantly increased than that in the control group, respectively (P<0.01). The amplification strips of PCR products in 5-FU, ASODN and combination groups were significantly weaker than that in the control group (P<0.01). The percentage of c-myc-protein- positive cells were significantly lower in antisense oligodeoxynucleotide, 5-fluorouracil and combination groups than that in the control group (P<0.01).

CONCLUSIONS

A liposome-mediated c-myc antisense oligodeoxynucleotide and 5-fluorouracil can inhibit the proliferation and invasion of liver cancer cells by reducing the expression of c-myc. A c-myc antisense oligodeoxynucleotide can increase the sensitivity of liver cancer cells to 5-fluorouracil and decrease the dosage of the agent necessary for efficacy, providing an experimental basis for the clinical therapy of liver cancer.

Pancreas-preserving duodenectomy for treatment of a duodenal papillary tumor: A case report

BACKGROUND

Duodenal papillary tumor is a rare tumor of the digestive tract, accounting for about 0.2% of gastrointestinal tumors and 7% of periampullary tumors. The clinical manifestations of biliary obstruction are most common. Some benign tumors or small malignant tumors are often not easily found because they have no obvious symptoms in the early stage. Surgical resection is the only treatment for duodenal papillary tumors. At present, the methods of operation for duodenal papillary tumors include pancreatoduodenectomy, duodenectomy, ampullectomy, and endoscopic resection.

CASE SUMMARY

A 47-year-old man was admitted to because of a duodenal mass that had been discovered 2 mo previously. Electronic gastroscopy at another hospital revealed a duodenal papillary mass that had been considered to be a high-grade intraepithelial neoplasia. Therefore, we conducted a multidisciplinary group discussion and decided to perform a pancreas-preserving duodenectomy and a R0 resection was successfully performed. After surgery, the patient underwent a follow-up period of 5 yr. No recurrence or metastasis occurred.

CONCLUSION

According to our experience with a duodenal papillary tumor, compared with pancreaticoduodenectomy, the use of pancreas-preserving duodenectomy can preserve pancreatic function, maintain gastrointestinal structure and function, reduce tissue damage and complications, and render the postoperative recovery faster. Pancreas-preserving duodenectomy for treatment of a duodenal papillary tumor is feasible under strict control of surgical indications.