Shiga toxin 2 A-subunit induces mitochondrial damage, mitophagy and apoptosis via the interaction of Tom20 in Caco-2 cells.

Shiga toxin type 2 (Stx2) is the primary virulence factor produced by Shiga toxin-producing enterohemorrhagic Escherichia coli (STEC), which causes epidemic outbreaks of gastrointestinal sickness and potentially fatal sequela hemolytic uremic syndrome (HUS). Most studies on Stx2-induced apoptosis have been performed with holotoxins, but the mechanism of how the A and B subunits of Stx2 cause apoptosis in cells is not clear. Here, we found that Stx2 A-subunit (Stx2A) induced mitochondrial damage, PINK1/Parkin-dependent mitophagy and apoptosis in Caco-2 cells. PINK1/Parkin-dependent mitophagy caused by Stx2A reduced apoptosis by decreasing the accumulation of reactive oxidative species (ROS). Mechanistically, Stx2A interacts with Tom20 on mitochondria to initiate the translocation of Bax to mitochondria, leading to mitochondrial damage and apoptosis. Overall, these data suggested that Stx2A induces mitochondrial damage, mitophagy and apoptosis via the interaction of Tom20 in Caco-2 cells and that mitophagy caused by Stx2A ameliorates apoptosis by eliminating damaged mitochondria. These findings provide evidence for the potential use of Tom20 inhibition as an anti-Shiga toxin therapy.

MicroRNA-31 induced by Fusobacterium nucleatum infection promotes colorectal cancer tumorigenesis.

Persistent Fusobacterium nucleatum infection is associated with the development of human colorectal cancer (CRC) and promotes tumorigenicity, but the underlying mechanisms remain unclear. Here, we reported that F. nucleatum promoted the tumorigenicity of CRC, which was associated with F. nucleatum-induced microRNA-31 (miR-31) expression in CRC tissues and cells. F. nucleatum infection inhibited autophagic flux by miR-31 through inhibiting syntaxin-12 (STX12) and was associated with the increased intracellular survival of F. nucleatum. Overexpression of miR-31 in CRC cells promoted their tumorigenicity by targeting eukaryotic initiation factor 4F-binding protein 1/2 (eIF4EBP1/2), whereas miR-31 knockout mice were resistant to the formation of colorectal tumors. In conclusion, F. nucleatum, miR-31, and STX12 form a closed loop in the autophagy pathway, and continuous F. nucleatum-induced miR-31 expression promotes the tumorigenicity of CRC cells by targeting eIF4EBP1/2. These findings reveal miR-31 as a potential diagnostic biomarker and therapeutic target in CRC patients with F. nucleatum infection.

Isolation of Fusobacterium nucleatum from human feces using immunomagnetic separation coupled with fastidious anaerobe agar.

AIM: Fusobacterium nucleatum (F. nucleatum) is associated with the initiation, development, and metastasis of colorectal cancer. However, it is difficult to isolate F. nucleatum from clinical specimens. In this study, we aimed to develop an effective and rapid method for isolating F. nucleatum from human feces using polyclonal antibody (PAB)-coated immunomagnetic beads (IMBs) with selective media. METHODS AND RESULTS: IMBs conjugated with PAB were prepared and used to isolate F. nucleatum from human feces, and the bacteria were cultured with selective culture media (fastidious anaerobe agar + nalidixic acid + vancomycin). Under optimized experimental conditions, IMBs could selectively recover F. nucleatum from fecal microbiota samples spiked with Peptostreptococcus or Bacteroides fragilis. In artificial fecal samples, the detection sensitivity of IMBs for F. nucleatum was 103 CFU mL-1. In addition, IMBs combined with selective media could rapidly isolate F. nucleatum from human feces. CONCLUSIONS: This study successfully established an effective method for the rapid isolation of F. nucleatum from human feces by IMBs. The whole procedure requires 2-3 days, and has a sensitivity of 103 CFU mL-1 feces.

Fusobacterium nucleatum induces excess methyltransferase-like 3-mediated microRNA-4717-3p maturation to promote colorectal cancer cell proliferation.

Fusobacterium nucleatum infection plays vital roles in colorectal cancer (CRC) progression. Overexpression of microRNA-4717-3p (miR-4717) was reported to be upregulated in F. nucleatum positive CRC tissues, however, the underlying mechanism is unknown. In this study, we found that miR-4717 promoted CRC cell proliferation in vitro and growth of CRC in vivo following F. nucleatum infection. MicroRNA-4717 suppressed the expression of mitogen-activated protein kinase kinase 4 (MAP2K4), a tumor suppressor, by directly targeting its 3'-UTR. Furthermore, we confirmed that methyltransferase-like 3 (METTL3)-dependent m6 A methylation could methylate primary (pri)-miR-4717, which further promoted the maturation of pri-miR-4717, and METTL3 positively regulated CRC cell proliferation through miR-4717/MAP2K4 pathways. In conclusion, F. nucleatum-induced miR-4717 excessive maturation through METTL3-dependent m6 A modification promotes CRC cell proliferation, which provides a potential therapeutic target and diagnostic biomarker for CRC.

Modulatory effect of metformin on cardiotoxicity induced by doxorubicin via the MAPK and AMPK pathways.

AIMS: Doxorubicin (DOX) is an effective anthracycline anticancer drug. However, the clinical usage of it is limited due to its severe cardiotoxicity side effects. Metformin (Met) is a kind of first-line antihyperglycemic drug which has a potential protective effect on the heart，it is often used for oral treatment of type 2 diabetes. In this study, we explored whether Met could attenuate cardiotoxicity induced by DOX. MATERIALS AND METHODS: For the sake of exploring the Met protective effect and mechanism, we established the DOX-induced cardiotoxicity models both in H9C2 cells incubated with 5 µM DOX in vitro and Sprague-Dawley rats treated with 20 mg/kg cumulative dose of DOX. KEY FINDINGS: Met is able to inhibit growth inhibition and apoptosis of H9C2 cells induced by DOX. The heart indexes of rats were examined to evaluate the Met cardiotoxicity protection. Met improved the abnormal indexes, serum markers of cardiac heart injury, echocardiography, electrocardiogram, cardiac pathology, cardiomyocyte apoptosis, and oxidative stress markers induced by DOX. Furthermore, in vivo and in vitro studies demonstrated that Met protected against DOX-induced increasing cleaved caspase-3 and Bax. Met also prevented the downregulation of Bcl-2, activated the AMPK pathway, and inhibited the MAPK pathway. SIGNIFICANCE: Met showed protective effects on DOX-induced cardiotoxicity by reducing oxidative stress and apoptosis, as well as regulating AMPK and MAPK signaling pathways.

Long-term oncologic outcomes of a randomized controlled trial comparing laparoscopic versus open gastrectomy with D2 lymph node dissection for advanced gastric cancer.

BACKGROUND: Laparoscopy-assisted gastrectomy is a feasible and safe procedure for treating advanced gastric cancer in terms of short-term outcomes. However, concern about long-term oncologic outcomes has limited the adoption of laparoscopy-assisted gastrectomy for advanced gastric cancer. METHODS: We launched a prospective randomized controlled trial comparing laparoscopic and open gastrectomy with D2 lymph node dissection for locally advanced gastric cancer to evaluate long-term oncologic feasibility. The 5-year overall survival, disease-free survival, and tumor recurrences have been determined on an intention-to-treat basis. RESULTS: Between January 2010 and June 2012, a total of 328 patients with preoperative clinical stage T2-4aN0-3M0 gastric cancer were enrolled in the trial. We excluded 6 patients with unresected tumor, and the remaining 322 patients were randomized to the laparoscopic group (162 patients) or the open group (160 patients) for radical surgery. One patient in laparoscopy-assisted gastrectomy and 4 patients in open gastrectomy were lost to follow-up immediately after discharge, leaving 317 patients (161 in laparoscopy-assisted gastrectomy and 156 in open gastrectomy) eligible for long-term analysis. The 5-year overall survival rate was 49.0% in the laparoscopic group and 50.7% in the open group, and the 5-year disease-free survival rate was 47.2% and 49.6% in the 2 groups, respectively. Kaplan-Meier curves for overall survival and disease-free survival showed no differences between the 2 groups. There was no difference in the 5-year tumor recurrence rate between the 2 procedures. CONCLUSION: Laparoscopy-assisted gastrectomy can provide comparable long-term survival without an increase in recurrence and metastasis in treating advanced gastric cancer.

Short-term surgical outcomes of a randomized controlled trial comparing laparoscopic versus open gastrectomy with D2 lymph node dissection for advanced gastric cancer.

BACKGROUND: Laparoscopy-assisted gastrectomy (LAG) has gained acceptance as one of the best treatments for early gastric cancer. However, the application of LAG with D2 lymph node dissection in patients with locally advanced gastric cancer (AGC) remains controversial. METHODS: We launched a prospective randomized controlled trial comparing laparoscopic and open gastrectomy with D2 lymph node dissection for locally AGC to evaluate technical safety and oncologic feasibility. The postoperative morbidity and mortality rates were based on the modified intention-to-treat analysis. RESULTS: Between January 2010 and June 2012, a total of 328 patients with preoperative clinical stage T2-3N0-3M0 gastric cancer were enrolled in the trial. Six patients with unresected AGC were excluded, and the remaining 322 patients were randomized to the laparoscopic group (162 patients) or the open group (160 patients) for radical surgery. All patients underwent D2 lymph node dissection including 18 (5.59%) proximal gastrectomies, 196 (60.87%) distal gastrectomies, and 108 (33.54%) total gastrectomies. Six patients (3.70%) in the LAG group were converted to open procedures. The overall complication rate was 11.72% in the LAG group and 14.38% in the open group (P = 0.512). No mortality occurred in either group. CONCLUSIONS: The short-term results of the current study suggest that LAG with D2 lymph node dissection is a safe and feasible procedure in treating patients with locally AGC in experienced centers.

Robotic Total Mesorectal Excision for Rectal Cancer: A Series of 392 Cases and Mid-Term Outcomes from A Single Center in China.

BACKGROUND: Robotic total mesorectal excision (RTME) for rectal cancer has recently been increasingly used; technical feasibility and short-term outcomes have been reported in detail. Few studies have presented clinical efficacy and mid-term outcomes for a large sample size. The aim of this study is to present oncologic efficacy and mid-term outcomes of robotic total mesorectal excision for rectal cancer and to provide our experiences regarding these surgically challenging issues. METHODS: Three hundred ninety-two patients received RTME between March 2010 and June 2015. Patient characteristics, perioperative clinical results, complications, pathologic details, recurrence, and mid-term outcomes were evaluated. RESULTS: Duration of surgery ranged from 80 to 388 min (median 224 min). There were no deaths during surgery and no anesthesiology complications in our series. The conversion rate was 1.1% (4/392). The postoperative complication rate was 10.2%; anastomosis leakage was the most common complication with an incidence of 4.1% (16/392). The median blood loss was 67.5±34.3 (20-600). The mean postoperative hospital stay was 12.1±6.1 (6-64). Circumferential resection margins were negative in 387 out of 392 cases (98.7%). The mean number of harvested lymph nodes was 14.6. Two deaths occurred during 30-day mortality. At a mean follow-up of 24 months (range 3-66 months), there were 35 deaths. CONCLUSION: Our results suggest that RTME is technically feasible for rectal cancer and can yield good short- and mid-term oncologic outcomes.

[Efficacy comparison of laparoscopic versus open distal gastrectomy with D2 lymph dissection for advanced gastric cancer].

OBJECTIVE: To evaluate the long-term clinical outcomes between laparoscopic and open distal gastrectomy with D2 lymph dissection for advanced gastric cancer. METHODS: Clinical data of 377 cases of laparoscopic distal gastrectomy and 301 cases of open distal gastrectomy with D2 lymph dissection at the Southwest Hospital, the Third Military Medical University from January 2004 to June 2010 were retrospectively analyzed. Patients were followed up until September 2015. Surgical outcomes, postoperative complications and long-term survival were compared between the two groups. RESULTS: Compared with conventional open group, laparoscopic group was associated with lower intraoperative blood loss [(125±89) ml vs. (290±161) ml, t=-15.942, P=0.000], shorter time to oral intake [(2.9±0.7) days vs. (4.1±1.6) days, t=-12.120, P=0.000], quicker bowel function retum[(2.7±1.4) days vs. (3.6±1.6) days, t=-7.804, P=0.000], shorter postoperative hospital stay [(7.7±3.6) days vs. (10.1±4.1) days, t=-8.107, P=0.000]. In addition, there were no significant differences in the operative time[(207±57) minutes vs. (202±43) minutes, P>0.05], number of retrieved lymph nodes(33±13 vs. 31±15, P>0.05), resection margin length(P>0.05) between two groups. The postoperative complication morbidity in laparoscopic group was significantly lower than that in open group[7.2%(22/377) vs. 12.6%(38/301), χ(2)=5.762, P=0.016]. Within perioperative period, 7 patients underwent operation again due to complication and 1 case died of peritoneal bleeding in laparoscopic group; 6 patients underwent re-operation and 2 cases died of peritoneal infection with hepatic failure and lung infection with respiratory failure. During the median follow-up of 86 months (range from 3-140 months), relapse occurred in 171(45.4%) patients and 183(48.5%, among them, 156 cases died of primary disease) patients died in laparoscopic group; relapse occurred in 140(46.5%) patients and 151(50.2%, among them, 127 cases died of primary disease) patients died in open group. The difference in overall 5-year survival rate between two groups was not statistically significant (51.5% vs. 49.8%, χ(2)=0.142, P=0.706). No significant difference was seen in 5-year disease-free survival rate (49.1% vs. 47.8%, χ(2)=0.062, P=0.803). Stratified analysis based on TNM stage also showed no significant difference in 5-year overall or disease-free survival rate(both P>0.05). CONCLUSION: Laparoscopic distal gastrectomy with D2 lymph dissection for advanced gastric cancer has better short-term efficacy and similar long-tern efficacy as compared to open surgery.

Novel method for esophagojejunal anastomosis after laparoscopic total gastrectomy: semi-end-to-end anastomosis.

AIM: To test a new safe and simple technique for circular-stapled esophagojejunostomy in laparoscopic total gastrectomy (LATG). METHODS: We selected 26 patients with gastric cancer who underwent LATG and Roux-en-Y gastrointestinal reconstruction with semi-end-to-end esophagojejunal anastomosis. RESULTS: LATG with semi-end-to-end esophagojejunal anastomosis was successfully performed in all 26 patients. The average operation time was 257 ± 36 min, with an average anastomosis time of 51 ± 17 min and an average intraoperative blood loss of 88 ± 46 mL. The average postoperative hospital stay was 8 ± 3 d. There were no complications and no mortality in this series. CONCLUSION: The application of semi-end-to-end esophagojejunal anastomosis after LATG is a safe and feasible procedure, which can be easily performed and has a short operation time in terms of anastomosis.

Suppression of vascular endothelial growth factor abrogates the immunosuppressive capability of murine gastric cancer cells and elicits antitumor immunity.

The mechanisms underlying immune evasion by gastric cancer have not been well described due to a lack of gastric tumor models in immunocompetent mice. In the current study, we found that supernatants from MFC cells, a murine gastric cancer line, inhibited the lipopolysaccharide (LPS) induced maturation and cross-presentation of bone-marrow-derived dendritic cells (BMDCs). Moreover, MFC tumor-derived factors markedly altered the cytokine profiles of BMDCs, leading to a trend of increased levels of interleukin 4 (IL4), IL6, IL23 and transforming growth factor ß, as well as decreased levels of tumor necrosis factor α. qPCR and ELISA revealed that MFC cells expressed a high level of vascular endothelial growth factor (VEGF). Downregulating VEGF expression abrogated the inhibitory effect of MFC-derived factors on the maturation and cross-presentation of BMDCs. In addition, VEGF knockdown greatly impaired the tumorigenicity of MFC cells in immunocompetent mice. Compared with parental MFC tumors, VEGF-low MFC tumors grew much more slowly and the survival of tumor-inoculated mice was significantly improved. More importantly, mice rejecting inoculated VEGF-low MFC tumor cells gained resistance to re-challenged parental tumors, which was attributed to an antitumor immunity response against parental MFC tumors. These results reveal an immunosuppressive role for VEGF in murine gastric cancer.

[Feasibility of radical laparoscopy-assisted gastrectomy for patients with chronic obstructive pulmonary disease].

OBJECTIVE: To assess the effect of radical laparoscopy-assisted gastrectomy(LG) for patients with chronic obstructive pulmonary disease (COPD). METHODS: Clinical data of 340 gastric cancer patients with COPD undergoing radical gastrectomy with lymphadenectomy at Southwest Hospital, Third Military Medical University between January 2010 and October 2013 were analyzed retrospectively. The clinical outcomes for the 262 patients with COPD who underwent LG(LG group) were compared with those of 78 patients with COPD who underwent open gastrectomy(OG group). During LG, pneumoperitoneum was maintained at an insuffiation pressure of 8 mmHg to 10 mmHg. The primary endpoint was postoperative pulmonary complication(PPC). To predict factors related to PPC, univariate and multivariate logistic analyses were carried out. RESULTS: Intraoperative blood loss was significantly less in the LG group [(131.2±14.7) ml] than in the OG group [(246.7±49.0) ml; t=-13.445, P=0.000], but operation time was significantly longer [(220.4±19.1) min vs. (194.2±31.5) min; t=6.877, P=0.000]. The findings showed PPC to be significantly less frequent in the LG group(5.3%,14/262) than in the OG group (15.4%, 12/78)(χ(2)=8.581, P=0.003). The severity of COPD was independent risk factor for PPC(P=0.031, HR=1.456, 95%CI:1.306-1.789). No independent predictor of PPCs was found in type of operative approach (open vs laparoscopic; P=0.126). CONCLUSION: The LG procedure with insuffiation pressure of pneumoperitoneum is tolerated for gastric cancer patients with mild or moderate COPD.

Aberrant expression of Cx43 is associated with the peritoneal metastasis of gastric cancer and Cx43-mediated gap junction enhances gastric cancer cell diapedesis from peritoneal mesothelium.

The process of peritoneal metastasis involves the diapedesis of intra-abdominal exfoliated gastric cancer cells through the mesothelial cell monolayers; however, the related molecular mechanisms for this process are still unclear. Heterocellular gap-junctional intercellular communication (GJIC) between gastric cancer cells and mesothelial cells may play an active role during diapedesis. In this study we detected the expression of connexin 43 (Cx43) in primary gastric cancer tissues, intra-abdominal exfoliated cancer cells, and matched metastatic peritoneal tissues. We found that the expression of Cx43 in primary gastric cancer tissues was significantly decreased; the intra-abdominal exfoliated cancer cells and matched metastatic peritoneal tissues exhibited increasing expression compared with primary gastric cancer tissues. BGC-823 and SGC-7901 human gastric cancer cells were engineered to express Cx43 or Cx43T154A (a mutant protein that only couples gap junctions but provides no intercellular communication) and were co-cultured with human peritoneal mesothelial cells (HPMCs). Heterocellular GJIC and diapedesis through HPMC monolayers on matrigel-coated coverslips were investigated. We found that BGC-823 and SGC-7901 gastric cancer cells expressing Cx43 formed functional heterocellular gap junctions with HPMC monolayers within one hour. A significant increase in diapedesis was observed in engineered Cx43-expressing cells compared with Cx43T154A and control group cells, which suggested that the observed upregulation of diapedesis in Cx43-expressing cells required heterocellular GJIC. Further study revealed that the gastric cancer cells transmigrated through the intercellular space between the mesothelial cells via a paracellular route. Our results suggest that the abnormal expression of Cx43 plays an essential role in peritoneal metastasis and that Cx43-mediated heterocellular GJIC between gastric cancer cells and mesothelial cells may be an important regulatory step during metastasis. Finally, we observed that the diapedesis of exfoliated gastric cancer cells through mesothelial barriers is a viable route of paracellular migration.

[Short-term efficacy of da Vinci robotic surgical system on rectal cancer in 101 patients].

OBJECTIVE: To investigate the feasibility and safety of da Vinci robotic surgical system in rectal cancer radical operation, and to summarize its short-term efficacy and clinical experience. METHODS: Data of 101 cases undergoing da Vinci robotic surgical system for rectal cancer radical operation from March 2010 to September 2012 were retrospectively analyzed. Evaluation was focused on operative procedure, complication, recovery and pathology. RESULTS: All the 101 cases underwent operation successfully and safely without conversion to open procedure. Rectal cancer radical operation with da Vinci robotic surgical system included 73 low anterior resections and 28 abdominoperineal resections. The average operative time was (210.3±47.2) min. The average blood lose was (60.5±28.7) ml without transfusion. Lymphadenectomy harvest was 17.3±5.4. Passage of first flatus was (2.7±0.7) d. Distal margin was (5.3±2.3) cm without residual cancer cells. The complication rate was 6.9%, including anastomotic leakage(n=2), perineum incision infection(n=2), pulmonary infection (n=2), urinary retention (n=1). There was no postoperative death. The mean follow-up time was(12.9±8.0) months. No local recurrence was found except 2 cases with distant metastasis. CONCLUSION: Application of da Vinci robotic surgical system in rectal cancer radical operation is safe and patients recover quickly The short-term efficacy is satisfactory.

Autophagy protects against oxaliplatin-induced cell death via ER stress and ROS in Caco-2 cells.

Oxaliplatin is included in a number of effective combination regimens used as first and subsequent lines of therapy for metastatic colorectal cancer. Accumulating evidence indicates that autophagy plays a significant role in response to cancer therapy. However, the role of autophagy in oxaliplatin-induced cell death remains to be clarified. In this study, we showed that oxaliplatin induced cell death and autophagy in Caco-2 colorectal cancer cells. The suppression of autophagy using either pharmacologic inhibitors (3-methyladenine, bafilomycin A1) or RNA interference in essential autophagy genes (ATG5 or Beclin1) enhanced the cell death and reactive oxygen species (ROS) production induced by oxaliplatin in Caco-2 cells. Blocking oxaliplatin-induced ROS production by using ROS scavengers (NAC or Tiron) decreased autophagy. Furthermore, numerous dilated endoplasmic reticula (ER) were present in oxaliplatin-treated Caco-2 cells, and blocking ER stress by RNA interference against candidate of metastasis-1 (P8) and C/EBP-homologous protein (CHOP) decreased autophagy and ROS production. Taken together, these data indicate that oxaliplatin activates autophagy as a cytoprotective response via ER stress and ROS in human colorectal cancer cells.

Mouse forestomach carcinoma cells immunosuppress macrophages through transforming growth factor-ß1.

Peritoneal implantation metastasis of gastric cancer cells is associated with poor prognosis. Peritoneal macrophages are the most important immune cells in the abdominal cavity to control tumor metastasis. In the present study, the immunosuppressive effects of mouse forestomach cells on macrophages were examined. Conditioned medium from mouse forestomach cell cultures were used to treat isolated peritoneal macrophages. A colorimetry-based phagocytosis assay was performed to investigate the functional change of macrophages. The alteration of cytokine secretion by macrophages was measured by ELISA assay. Specific markers of macrophage polarization were analyzed by real-time RT-PCR. TGF-ß1 signaling was evaluated by western blotting. Neutralization experiments were performed using an anti-TGF-ß1 antibody. Conditioned medium reduced the phagocytotic capability of macrophages. Lower TNF-α and IL-1ß levels and higher IL-10 and VEGF levels were observed. Real-time RT-PCR showed increased mRNA levels of M2 macrophage markers. Further study revealed that TGF-ß1 was significantly elevated in the conditioned medium and TGF-ß1 signaling was activated in the macrophages by the treatment of conditioned medium. Neutralization of TGF-ß1 reversed the immunosuppressive effects on macrophages. Immunosuppressive macrophages can be induced by conditioned medium from mouse forestomach cell cultures. These effects appeared to occur through the production of TGF-ß1 by the tumor cells. Targeted TGF-ß1 intervention may help to control peritoneal metastasis of gastric cancers.

Mouse forestomach carcinoma cells immunosuppress macrophages through TGF-ß1.

BACKGROUND/AIMS: Peritoneal implantation metastasis of gastric cancer cells is associated with poor prognosis. Peritoneal macrophages are the most important immune cells in the abdominal cavity to control tumor metastasis. In the present study, the immunosuppressive effects of mouse forestomach cells on macrophages were examined. MATERIALS AND METHODS: Conditioned medium from mouse forestomach cell cultures were used to treat isolated peritoneal macrophages. A colorimetry-based phagocytosis assay was performed to investigate the functional change of macrophages. The alternation in cytokine secretion by macrophages was measured by enzyme-linked immunosorbent assay. Specific markers of macrophage polarization were analyzed by real-time reverse transcription polymerase chain reaction. The transforming growth factor-ß1 signaling was evaluated by Western blotting. Neutralization experiments were performed by using transforming growth factor-ß1 antibody. RESULTS: The conditioned medium reduced the phagocytotic capability of macrophages. Lower tumor necrosis factor-α and interleukin-1ß levels and higher interleukin-10 and vascular endothelial growth factor levels were observed. Real-time reverse transcription polymerase chain reaction showed increased mRNA levels of M2 macrophage markers. Further study revealed that transforming growth factor-ß1 was significantly elevated in the conditioned medium and transforming growth factor-ß1 signaling was activated in the macrophages with treatment with conditioned medium. Neutralization of transforming growth factor-ß1 reversed the immunosuppressive effects on macrophages. CONCLUSIONS: Immunosuppressive macrophages can be induced by conditioned medium from mouse forestomach cell cultures. These effects seemed to be through the production of transforming growth factor-ß1 by the tumor cells. Targeting transforming growth factor-ß1 intervention might help in the control of peritoneal metastasis of gastric cancers.

Comparison of outcomes for laparoscopically assisted and open radical distal gastrectomy with lymphadenectomy for advanced gastric cancer.

BACKGROUND: Laparoscopically assisted gastric surgery has become an option for the treatment of early gastric cancer. However, the feasibility and safety of laparoscopically assisted gastrectomy for advanced gastric cancer has rarely been studied. This study evaluated the short- and long-term outcomes of laparoscopically assisted distal gastrectomy (LADG) for advanced gastric cancer. METHODS: The study retrospectively analyzed the clinical and follow-up data for 346 cases after LADG and for 313 cases after conventional open distal gastrectomy (ODG) used to treat advanced gastric cancer from January 2004 to June 2009 at the authors' hospital. The surgical safety, postoperative complications, survival rate, and recurrence and metastasis of cancer were compared between the LADG and ODG groups. RESULTS: The average time for the LADG and ODG procedures did not differ significantly (211 ± 56 vs 204 ± 41 min), but bleeding during the operation and incision length in the LADG group were significantly less than in the ODG group. The proximal and distal margins of tumors were, respectively, 6.25 ± 2.04 and 5.68 ± 1.71 cm in the LADG group compared with 6.29 ± 2.11 and 5.62 ± 1.59 cm in the ODG group. Neither intergroup difference was significant. The number of lymph node dissections also was similar in the two groups: 33.2 ± 12.5 in the LADG group and 32.8 ± 15.6 in the ODG group. The incidence of postoperative complications in the LADG group (6.7%) was significantly lower than in the ODG group (13.1%). During the follow-up period of 6 to 72 months (average, 37 months), the survival rates were 87.2% at 1 year, 57.2% at 3 years, and 50.30% at 5 years in the LADG group compared with 87.1% at 1 year, 54.1% at 3 years, and 49.2% at 5 years in the ODG group (all similar between the groups). The differences in recurrence and metastasis between the two groups were not statistically significant. CONCLUSION: Laparoscopically assisted gastrectomy for advanced gastric cancer is safe and effective. In this study, it did not differ significantly from open surgery in terms of survival rate or recurrence after surgery based on long-term follow-up evaluation. It can achieve the same beneficial effects as open surgery, and it has the advantages of a small operation wound, less bleeding, good safety, rapid postoperative recovery, and fewer complications.

Laparoscopy-assisted resection for gastric stump cancer and gastric stump recurrent cancer: a report of 15 cases.

OBJECTIVE: This study was designed to investigate the technical methods and clinical therapeutic effects of laparoscopy-assisted resection of gastric stump cancer (GSC). METHODS: Laparoscopy-assisted resection was performed on 15 patients with GSC. The approach, method, difficult points, and techniques of the operation were analyzed, and its clinical therapeutic effect was evaluated. RESULTS: With the help of laparoscopy, D2 radical resection of gastric stump was performed on 12 patients, and palliative gastric stump resection was performed on two patients. There was one case of conversion from laparoscopic surgery to open surgery. Roux-en-Y gastric bypass was performed in all cases to reconstruct the alimentary tract. The mean operative time for laparoscopy-assisted resection was 205 ± 25 min. The mean intraoperative blood loss volume was 110 ± 40 ml. The mean number of lymph nodes removed was 18 ± 5. A gastric tube was not placed in the patients after surgery. The mean time for the recovery of intestinal function was 2.5 ± 1 days, the mean duration of postoperative liquid diet was 2.5 ± 1 days, and the mean time for the recovery of ambulatory activity was 3 ± 0.5 days. There was one case of postoperative infection of the incision site. The follow-up time was 6-40 months, with 1 case of death due to liver metastasis, 1 case of death due to peritoneal metastasis, 1 case of death due to complications from lupus erythematosus, and survival for the remaining 12 cases. CONCLUSIONS: Laparoscopy-assisted resection of GSC is technically feasible; determination of the short- and long-term efficacies will require a larger and comparative sample study.

[A modified method of laparoscopic side-to-side esophagojejunal anastomosis after laparoscopic total gastrectomy: a report of 12 cases].

OBJECTIVE: To explore the method of alimentary reconstruction after laparoscopic total gastrectomy. METHODS: The clinical data of 12 patients undergone laparoscopic total gastrectomy and side- to- side esophagojejunal anastomosis from Feb. 2006 to Oct. 2006 were analyzed retrospectively. RESULTS: Laparoscopic side- to- side esophagojejunal anastomosis was successfully performed in 12 patients. The mean operation time was (247.0+/- 13.1) min and the anastomosis time was (43.5+/- 10.4) min. Bleeding volume during operation was (107.5+/- 44.9)ml. The distance between anastomosis and proximal margin of tumor was (3.4+/- 1.2)cm. There was no postoperative death, fistula or anastomotic stenosis occurred after short- term follow- up. CONCLUSION: The modified laparoscopic side- to- side esophagojejunal anastomosis is a safe, less challenging and more economic method of alimentary reconstruction after laparoscopic total gastrectomy.