Comparison of Distal Transradial and Femoral Access in Endovascular Treatment of Non-coronary Arterial Disease.

This study compared the efficacy and safety of distal transradial access (dTRA) and common femoral artery access (CFA) for endovascular treatment of non-coronary arterial disease. 102 interventions were divided into dTRA (n = 51) and CFA (n = 51) groups; the puncture success rate was 100% in both groups. The mean number of punctures and puncture time were greater in the dTRA than CFA group (1.86 vs 1.04 and 3.96 vs ≤1.00 min, p < .001 for both), whereas the access-related complication rate was comparable. The surgical success rate was higher in the CFA than dTRA group (98.0 vs 84.3, p = .036), and the operative time was longer in the dTRA than CFA group (99.09 vs 84.10 min, p = .017). The postoperative adverse event rate was not different between the dTRA and CFA groups. dTRA is a safe and feasible access for non-coronary arterial disease and is comparable to CFA in terms of puncture success, access-related complications, and major adverse events. The dTRA is inferior to CFA in the treatment of lower extremity arterial disease. Due to the increase in the operation time and the contrast medium volume in the dTRA, it is necessary to be vigilant about contrast nephropathy and late radiological random side effects.

Overexpression of Tie2 is associated with poor prognosis in patients with gastric cancer.

Tunica Interna endothelial cell kinase (Tie2)-expressing macrophages (TEMs) are a subgroup of tumor-associated macrophages that are associated with a poor prognosis in numerous types of cancer. The present study aimed to assess the prognostic impact of Tie2 expression in gastric cancer tissues. Between January 2009 and December 2009, 76 newly diagnosed patients with gastric cancer at the Southwest Hospital, Third Military Medical University (Chongqing, China) were enrolled. TEMs were detected using immunohistochemistry. Tie2, cluster of differentiation (CD)68 and carbonic anhydrase IX (CAIX) were analyzed using immunohistochemistry and immunofluorescent microscopy. Tie2 protein expression was analyzed using western blot analysis in hypoxic and normoxic gastric cancer tissues. The number of TEMs positively staining for Tie2 increased with the tumor-node-metastasis (TNM) stage: 0, 53.9, 75.6 and 100% in stages I, II, III and IV, respectively (P<0.001). Tumor size and lymph node involvement were significantly associated with the presence of Tie2 in the tumor stroma (P<0.001). There was no significant difference between Tie2 and CAIX, irrespective of how the patients were grouped (tumor size, lymph node involvement, TNM stage or histological grade). Tie2 protein expression was increased in the hypoxic regions of gastric tumors.Tie2 and CD68 expression colocalized in hypoxic and normoxic gastric cancer tissues. The 1-, 2- and 3-year recurrence rates of the TEM-positive group were 31.4, 56.9 and 66.7%, respectively, as compared with 8, 28 and 48%, respectively, for the TEM-negative group (P<0.05). In the TEM-negative group, 2 patients succumbed to the disease, as compared with 21 patients in the TEM-positive group (P<0.05). Therefore, high quantities of TEMs, represented by Tie2 expression, in gastric tumors may be associated with poor survival.

A retrospective, single-center cohort study on 65 patients with primary retroperitoneal liposarcoma.

Primary retroperitoneal liposarcoma (PRPLS) is the most common soft tissue malignancy of the retroperitoneum. To determine the pathological features and the curative effects of surgery in patients with PRPLS, and to elucidate key prognostic factors, the present study retrospectively analyzed the clinical cases of 65 patients with PRPLS. Immunohistochemical analysis demonstrated that vimentin and Ki-67 are better indicators for PRPLS immunohistochemical diagnosis compared with S-100 protein. S-100 protein was predominantly expressed in well-differentiated PRPLS. Positive expression of vimentin and Ki-67 were observed in almost all PRPLS samples, and Ki-67 exhibited a higher expression level in high-grade PRPLS. The level of Ki-67 expression was negatively correlated with disease-specific survival (DSS). Survival analysis revealed that the pathological subtype and histological grade were associated with DSS and local recurrence in the patients, whereas the tumor burden was associated with DSS but not local recurrence. In addition, complete tumor resection and contiguous organ resection were able to improve DSS. Microscopically positive margins did not affect DSS, whereas gross margins did. Multivariate analysis revealed that pathological subtype, histological grade and contiguous organ resection were independent prognostic factors, and that histological grade was an independent factor for local recurrence. Patient sex and age at presentation were not independent factors associated with prognosis or local recurrence. Correlation analysis demonstrated that postoperative local recurrence significantly affected DSS, and local recurrence was the most common cause of mortality among patients. Histological grade was strongly associated with the invasion of adjacent organs but not with tumor burden. Furthermore, the tumor burden was not associated with recurrence or tumor invasion of adjacent organs. Ki-67 expression was associated with prognosis. Pathological subtype, histological grade and contiguous organ resection were independent prognostic factors, while histological grade was an independent factor which affected tumor recurrence.

HIF-1α induces the epithelial-mesenchymal transition in gastric cancer stem cells through the Snail pathway.

Substantial evidence suggests that the epithelial-mesenchymal transition (EMT) phenotype is associated with the invasive characteristics of cancer stem cells (CSCs),which possess an EMT phenotype that may predominate in tumor invasion and metastasis. However, the mechanisms for the generation and regulation of these CSCs have not been clearly defined. As hypoxia and EMT-related factors may have important functions in EMT-like CSCs, the aim of this study was to investigate the effects of hypoxia on these cells. CSCs were established from the gastric cancer cell lines MGC-803 and SGC7901, and the relationship between hypoxia and EMT-like CSCs was investigated in gastric cancer. After hypoxia treatment, some gastric CSCs exhibited a marked increase in hypoxia-inducible factor-1α (HIF-1α)expression and increased migration and invasion capabilities compared with the normoxic control. These CSCs were defined by activation of the mesenchymal cell marker Vimentin and by inhibition of the epithelial cell marker E-cadherin. Our analyses also show that HIF-1α was responsible for activating EMT via increased expression of the transcription factor Snail in gastric CSCs. Moreover, inhibition of Snail by shRNA reduced HIF-1α-induced EMT in gastric CSCs. The results demonstrated that hypoxia-induced EMT-like CSCs rely on HIF-1αto activate Snail, which may result in recurrence and metastasis of gastric cancer.

Increased chemokine receptor IL-17RA expression is associated with poor survival in gastric cancer patients.

BACKGROUND: Previous researchers have identified that the chemokine interleukin-17 (IL-17) was associated with survival time of patients with gastric cancer, but the roles of its receptors (IL-17R) in gastric cancer remain unknown. Our studies were designed to clarify the function of IL-17RA and to explore their potential role in gastric cancer. MATERIALS AND METHODS: The expression of IL-17RA was determined in primary gastric cancer tissues (n=101) using Real-time RT-PCR, immunohistochemistry, and western blotting. To investigate the functional significance of IL-17RA expression, IL-17RA expression and clinical parameters, multivariate survival was analyzed in patients with gastric cancer. RESULTS: IL-17RA was overexpression in gastric cancer tissues compared with adjacent normal tissues (P<0.05). The elevated expression level of IL-17RA was observed correlated significantly with tumor progression (P=0.003), Lymphatic invasion (P=0.019), lymphoid nodal status (P=0.001), distant metastasis (P<0.001) of gastric cancer patients, TNM stage (P=0.0013) and was one of the independent prognostic factors for patient's overall survival. CONCLUSIONS: These results demonstrated that the expression of IL-17RA plays an important role in gastric cancer progression, migration and prognosis of gastric cancer. The IL-17-IL-17RA signaling mechanism may be a potential novel target.

Chloride intracellular channel 1 regulates colon cancer cell migration and invasion through ROS/ERK pathway.

AIM: To investigate the mechanisms of chloride intracellular channel 1 (CLIC1) in the metastasis of colon cancer under hypoxia-reoxygenation (H-R) conditions. METHODS: Fluorescent probes were used to detect reactive oxygen species (ROS) in LOVO cells. Wound healing assay and transwell assay were performed to examine the migration and invasion of LOVO cells. Expression of CLIC1 mRNA and protein, p-ERK, MMP-2 and MMP-9 proteins was analyzed by reverse transcription-polymerase chain reaction and Western blot. METHODS: H-R treatment increased the intracellular ROS level in LOVO cells. The mRNA and protein expression of CLIC1 was elevated under H-R conditions. Functional inhibition of CLIC1 markedly decreased the H-R-enhanced ROS generation, cell migration, invasion and phosphorylation of ERK in treated LOVO cells. Additionally, the expression of MMP-2 and MMP-9 could be regulated by CLIC1-mediated ROS/ERK pathway. CONCLUSION: Our results suggest that CLIC1 protein is involved in the metastasis of colon cancer LOVO cells via regulating the ROS/ERK pathway in the H-R process.

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.

[Influence of CO2 pneumoperitoneum pressures on the expression of adhesion molecules of gastric cancer cells].

OBJECTIVE: To study the effect of different CO2 pneumoperitoneum pressures on the expression of adhesion molecules of human gastric cancer cell line MNK-45. METHODS: MKN-45 cells in the experimental groups were exposed to simulated CO2 environment maintained at different pressures (1.2, 1.6, 2.0 kPa) for 4 hours. Control groups were exposed to room air. At the 0, 24, 48, 72, 96 hours after treatment, CD44v6, ICAM-1 and E-cadherin were detected by flow cytometry method. RESULTS: CD44v6 and ICAM-1 expressions showed pattern of firstly elevating, then descending to normal under the pressures of 1.2 kPa and 1.6 kPa. The expressions were different from control group significantly at 24 and 48 hours (P<0.01), while the 72 hours expression showed no difference compared with the controls (P>0.05). E-cadherin expression decreased significantly right after treatment compared to the control (P<0.01), but recovered to the level of control at 48 hours (P>0.05). In the 2.0 kPa group the expression changes of CD44v6, ICAM-1 and E-cadherin were more remarkable. CD44v6 and ICAM-1 expressions were increased significantly compared to control right after treatment (P<0.05). E-cadherin expression was significantly decreased even at 48 hours compared to the controls (P<0.01). CONCLUSION: In vitro CO2 pneumoperitoneum pressures have transient influence on the adhesion molecules expression of gastric cancer cell MKN-45, then those expressions can recover in a short-time.

[Robotic-assisted radical gastrectomy using da Vinci robotic system: a report of 41 cases].

OBJECTIVE: To investigate the feasibility and safety of da Vinci robotic-assisted radical gastrectomy for gastric cancer. METHODS: Forty-one patients with gastric cancer from Southwest Hospital between March 2010 and December 2011 underwent da Vinci robotic-assisted radical gastrectomy including total gastrectomy(n=12) and distal gastrectomy (n=29). RESULTS: Conversion was required in two patients. One was converted to open surgery, and the other to conventional laparoscopic surgery. The remaining thirty-nine patients underwent da Vinci robotic-assisted radical gastrectomy successfully. The mean operative time was (285±61) min for total gastrectomy, and (225±39) min for distal gastrectomy. The mean blood loss was (180±157) ml in total gastrectomy, and (150±127) ml in distal gastrectomy. The mean number of harvested lymph nodes was 34.2±18.5. The mean time for gastrointestinal function recovery was (3.1±1.2) days. The time to ambulation was (2.7±1.5) days. The time to oral liquid intake was (3.7±1.5) days. Two patients had complication including wound infection and pneumonia. After follow up ranging from 1 to 21 months (median 11 months), 4 patients died from peritoneal metastasis, 1 survived with tumor, and the remaining 36 patients survived without disease. CONCLUSIONS: da Vinci robotic-assisted radical gastrectomy is a feasible and safe surgical procedure with clear operation field, precise dissection, minimal trauma and fast recovery.

[Effects of hypoxia-inducible factor-1α on human gastric cancer cell apoptosis under in vitro CO(2) pneumoperitoneum environment].

OBJECTIVE: To study the effect of hypoxia-inducible factor-1α (HIF-1α) on human gastric cancer cells apoptosis in simulated CO2 pneumoperitoneum environment. METHODS: Applied closed box to simulated CO2 pneumoperitoneum environment under the pressure of 0, 5, 10 and 15 mm Hg (1 mm Hg = 0.133 kPa). Compared HIF-1α mRNA and protein expression of MKN-45 cells before and after silencing HIF-1α by RT-PCR and Western blot. Study the changes of bcl-2/bax expression in MKN-45 cells before and after silencing HIF-1α by immunohistochemistry. The apoptosis ratio of MKN-45 was measured by using Annexin V-FITC/PI double labelled staining. RESULTS: In 15 mm Hg group, HIF-1α mRNA and protein expression of MKN-45 cells (1.48 ± 0.22, 1.34 ± 0.09) and HIF-1α protein expression in 10 mm Hg group (1.25 ± 0.10) were significantly higher than those in control group (0.55 ± 0.17, 0.83 ± 0.04) (P < 0.05). But there was no significant differences among 0, 5, 10 mm Hg group and control group in HIF-1α mRNA (P > 0.05); and no obvious difference was found among 0, 5 mm Hg group and the control group in HIF-1α protein expression (P > 0.05). In 15 mm Hg CO2 pressure, bcl-2/bax expression (0.78 ± 0.05) was obviously lower than that in the control group (1.43 ± 0.15) (P < 0.05) and the apoptosis ratio (11.70 ± 0.12) was significantly higher than the control group (0.22 ± 0.07) (P < 0.01) before silencing HIF-1α. But once HIF-1α was silenced, HIF-1α mRNA (0.52 ± 0.11), HIF-1α protein expression (0.92 ± 0.02), bcl-2/bax ratio (1.57 ± 0.04) and apoptosis ratio (0.45 ± 0.11) in MKN-45 were not significantly different between 15 mm Hg group and the control group (P > 0.05). CONCLUSIONS: The apoptosis ratios of MKN-45 under 0, 5, 10 mm Hg CO2 pneumoperitoneum are comparable with that in the control group before the silencing of HIF-1α. The apoptosis ratio of MKN-45 is increased under 15 mm Hg CO2 pneumoperitoneum environment and HIF-1α may be one of the important factor to improve the apoptosis of human gastric cancer cell.

[Expression of Na+-H+ exchanger 1 in human gastric carcinoma tissue and its clinical significance].

OBJECTIVE: To determine the expression of Na+/H+ exchanger 1(NHE1) in human gastric carcinoma tissue and to investigate the association between NHE1 expression and clinicopathological characteristics. METHODS: The expressions of NHE1 mRNA and protein were detected in both gastric carcinoma tissue (n=60) and adjacent gastric mucosa tissue (n=30) by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. The association between the expression and the clinicopathological characteristics was analyzed. RESULTS: The relative expression levels of NHE1 mRNA and protein in gastric carcinoma tissue were 0.786+/-0.291 and 1.442+/-0.175, which were significantly higher than those in adjacent gastric mucosa tissue (0.369+/-0.052 and 0.348+/-0.029) (P<0.01). The expression of NHE1 mRNA was positively correlated with NHE1 protein in the gastric carcinoma tissue (r=0.264, P<0.05). The expressions of NHE1 mRNA and protein were associated with the depth of invasion, lymph node metastasis, and TNM staging (P<0.05). However, no statistical difference was found in age, gender, and tumor differentiation (P>0.05). CONCLUSION: The expression levels of NHE1 mRNA and protein are significantly up-regulated in gastric carcinoma tissue, which may be involved in the development of gastric carcinoma.

Inhibition effects of high mechanical index ultrasound contrast on hepatic metastasis of cancer in a rat model.

RATIONAL AND OBJECTIVES: The liver is the most common organ for tumor metastasis. The development of new methods to depress hepatic metastasis is of great importance in improving survival. The aim of this study was to observe the effects of high-mechanical index ultrasound contrast on hepatic metastasis of colorectal cancer. MATERIALS AND METHODS: Hepatic metastasis models were established by injecting human colon carcinoma LoVo cells into the spleens of Sprague-Dawley rats. The rats were divided into a control group, a microbubble plus ultrasound group, a simple ultrasound group, and a simple microbubble group. The ultrasound contrast agent SonoVue (1 mL/kg) was injected via the tail vein, and high-mechanical index ultrasound contrast (frequency, 1.5 MHz; mechanical index, 1.7) was performed on the spleen intermittently for 2 minutes. The animals were sacrificed after 10 days, and the sizes and number of hepatic metastases were measured and compared. Histologic pathology and splenic ultrastructure were observed. RESULTS: The number and sizes of hepatic metastases patently decreased in rats in the microbubble plus ultrasound group (P < .01). There were no obvious differences among the control group, simple ultrasound group, and simple microbubble group in hepatic metastases (P > .05). Histologic pathology showed that the number of tumor cells in the spleens decreased considerably, and massive necroses, hemorrhages, and thrombi were observed in the tumor and spleen tissues of rats in the microbubble plus ultrasound group. Transmission electron microscopy showed that the mitochondria of tumor cells and endothelial cells were clearly swelled, and there were gaps among endothelial cells and platelets aggregated in capillary vessels. CONCLUSION: This research shows that intermittent high-mechanical index ultrasound contrast may inhibit the hepatic metastasis of cancer in a rat model.

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.

[Effect of JAK2/STAT3/vimentin signaling pathway on proliferation and migration of human colon cancer cells].

OBJECTIVE: To investigate the regulatory role of JAK2/STAT3/vimentin signaling pathway on the proliferation and migration of human colon cancer cells. METHODS: The human colon cancer cell Lovo was treated with Janus kinase inhibitor AG490. The proliferation of Lovo cells was quantified by MTT assay. The migration of Lovo cells was measured with scratch assay. The intracellular phosphorylation STAT3 (P-STAT3) and vimentin protein was detected by Western blot and immunofluorescence. RESULTS: After AG490 treatment, the proliferative ability of Lovo cells decreased as compared with control group (P<0.05). This suppression was dose-independent and time-independent. At 24 hrs after scratching, scratch width in the AG490 group recovered to 20%, lower than that in the control group (60%, P<0.05). After AG490 treatment, the expression of P-STAT3 and vimentin in Lovo cells decreased significantly (P<0.05). CONCLUSION: JAK2/STAT3/vimentin signaling pathway participates in regulating the proliferation and migration of human colon cancer cells.

Influence of laparoscopic gastrectomy on the detection rate of free gastric cancer cells in the peritoneal cavity.

BACKGROUND: Whether laparoscopic gastrectomy affects the number of gastric cancer cells exfoliated from the cancer-invaded serosa remains unclear. This study aimed to compare the detection rate of free gastric cancer cells in the peritoneal cavity during laparoscopic and open gastrectomy. METHODS: Intraoperative peritoneal washings were collected from 83 gastric cancer patients undergoing laparoscopic gastrectomy and 81 patients undergoing open surgery. Hematoxylin and eosin (H&E) staining and real-time reverse-transcription polymerase chain reaction (RT-PCR) were used to examine the free cancer cells. RESULTS: The postoperative positive rates of free cancer cells detected by cytological and real-time RT-PCR were 39.76 and 43.20% in the laparoscopic and open groups, respectively. Depth of tumor invasion, area of invaded serosa, regional lymph node involvement, and higher pathological staging were significantly associated with presence of free cancer cells. CONCLUSION: The laparoscopic techniques used in gastric cancer surgery did not increase the detection rate of free cancer cells in the peritoneal cavity compared with conventional techniques.

Comparison of laparoscopic and open gastrectomy on cancer cells exfoliating from the cancer-invaded serosa.

BACKGROUND: Whether laparoscopic gastrectomy may reduce the frequency of gastric cancer cells exfoliating from the cancer-invaded serosa remains unclear. This study aimed to compare the detection of free gastric cancer cells in the peritoneal cavity during laparoscopic and open gastrectomy. METHODS: Intraoperative peritoneal washings were collected from 63 gastric cancer patients undergoing laparoscopic gastrectomy and 61 patients undergoing open surgery. Hematoxylin and eosin staining and real time reverse transcription-polymerase chain reaction were used to examine the free cancer cells. RESULTS: The postoperative positive rates of free cancer cells detected by cytologic and real time reverse transcription-polymerase chain reaction were 39.68% and 44.26% in the laparoscopic and open groups, respectively. The depth of tumor invasion, area of invaded serosa, regional lymph node involvement, and higher tumor node metastasis staging were significantly associated with the presence of free cancer cells. CONCLUSIONS: The laparoscopic techniques used in gastric cancer surgery were not associated with a greater risk for the intraperitoneal dissemination of cancer cells than conventional techniques.

Effects of HIF-1alpha on human gastric cancer cell apoptosis at different CO(2) pressures.

The effects and potential molecular mechanisms underlying carbon dioxide (CO(2)) pneumoperitoneum on gastric cancer cell apoptosis are not fully understood. In this study, we assessed the effects of CO(2) pneumoperitoneum on the apoptosis of MKN-45 gastric cancer cells. Additionally, we investigated the role of HIF-1alpha in CO(2) pneumoperitoneum-induced apoptosis of gastric cancer cells. MKN-45 cells were cultured in CO(2) or air pneumoperitoneum at 0, 12 and 15 mmHg pressures for 4 h. We observed a change in cells morphology and increasing apoptotic ratios in MKN-45 cells when they were put into a 15 mmHg CO(2) pneumoperitoneum environment. However, there was no significant difference between the 0, 12 mmHg CO(2) pneumoperitoneum and the control groups. Exposure to 15 mmHg CO(2) pneumoperitoneum significantly enhanced the expression levels of HIF-1alpha and Bax, while it attenuated Bcl-2 expression levels. When we inhibited HIF-1alpha by small interfering RNA (siRNA), we found that the apoptotic ratio of MKN-45 cells decreased in 15 mmHg CO(2) pneumoperitoneum. This treatment markedly elevated Bcl-2 levels and decreased Bax expression. These data suggest that CO(2) pneumoperitoneum may accelerate the apoptosis of MKN-45 cells at higher pressures. HIF-1alpha is a crucial factor that affects gastric cancer cell apoptosis by downregulating the Bcl-2/Bax ratio.