[Growth inhibition of breast cancer cells in vitro and in vivo by siRNA targeting signal transducers and activators of transcription 3].

OBJECTIVE: To observe the effect of signal transducers and activators of transcription 3 (STAT3) gene silence on the growth of breast cancer cell line MCF7 in vitro and in vivo and discuss the feasibility and effectiveness of STAT3 used as gene therapeutic target for breast cancer. METHODS: Human breast cancer cell line MCF7 cells were divided into 3 groups: mock control group, control group transfected with scrambled sequence siRNA, and experimental group transfectod with STAT3 siRNA. The STAT3 mRNA and protein levels were detected by semi-quantity RT-PCR and Western blotting, respectively. The cell proliferation and apoptosis were examined by MTT method and flow cytometry. MCF7 cells treated with STAT3-siRNA were transplanted subcutaneously in nude mice and their tumorgenic ability was observed. The STAT3 mRNA and protein levels of the samples from nude mice of different groups were detected by semi-quantity RT-PCR and Western blotting and compared. RESULTS: After treatment with STAT3-siRNA, STAT3 mRNA (0.327 ± 0.020 vs. 1.035 ± 0.050, 1.093 ± 0.018) and ptotein (0.153 ± 0.006 vs. 1.320 ± 0.033, 1.374 ± 0.022) levels in the MCF7 cells transfected with STAT3-siRNA were significantly lower than that in the two control groups (P < 0.05). MTT assay showed that after transfection of the STAT3-siRNA into MCF7 cells, cell proliferation was significantly reduced and the cell growth inhibition ratio in the STAT3-siRNA group was (44.00 ± 5.10)%, significantly higher than that in the control group (16.1 ± 1.05)% (P < 0.05). Flow cytometry results suggested that more apoptosis was observed in the STAT3-siRNA group. The apoptosis rate was (14.79 ± 0.22)%, much higher than that in the control group [(7.06 ± 0.71)%, (8.45 ± 0.43)%, P < 0.05]. The tumor growth in the experimental group was significantly slower than that in the two control groups. 0n the 22th day after transplantation, the tumor weight [(21.4 ± 10.6) mg vs. (88.6 ± 12.2) mg, (57.2 ± 21.9) mg] and volume [(41.15 ± 12.17) mm³ vs. (118.45 ± 24.68) mm³, (101.36 ± 21.90) mm³] in the experimental group were significantly lower than that in the two control groups (P < 0.05). The STAT3 mRNA and protein levels of the samples from nude mice in the experimental group were significantly lower than that in the two control groups. CONCLUSION: siRNA targeting STAT3 can inhibit the proliferation of MCF7 cells in vitro and in vivo. STAT3 may become a novel therapeutic target for breast cancer.

Renal ischemia/reperfusion injury in rats is attenuated by a synthetic glycine derivative.

Renal ischemia/reperfusion is a common cause of acute renal failure. Glycine is an effective anti-inflammatory, cytoprotective agent and is reported to have a beneficial effect against ischemia/reperfusion injury in various organs. Previous research notes that free radicals and inflammatory leukocytes both play important roles in the pathogenesis of renal ischemia/reperfusion injury. To develop new therapeutic agents against renal ischemia/reperfusion injury, we sought to link an antioxidant moiety (nitronyl nitroxide) to glycine in the hope that the resulting glycine-nitronyl nitroxide conjugate (GNN) would provide a synergetic protection against renal ischemia/reperfusion injury. In this manuscript, we report the synthesis and biological evaluation of the GNN conjugate. The biological activity of the GNN conjugate was evaluated in an in vivo rat model of renal ischemia/reperfusion induced injury and oxidative change. Since the GNN conjugate markedly reduced elevated levels of tissue lipid peroxidation and attenuated renal dysfunction in rats subjected to renal ischemia/reperfusion, it might be possible to develop the GNN conjugate into a potential therapeutic agent against renal ischemia/reperfusion injury.

Ultrasonically activated scalpel versus monopolar electrocautery shovel in laparoscopic total mesorectal excision for rectal cancer.

AIM: To investigate the feasibility and safety of monopolar electrocautery shovel (ES) in laparoscopic total mesorectal excision (TME) with anal sphincter preservation for rectal cancer in order to reduce the cost of the laparoscopic operation, and to compare ES with the ultrasonically activated scalpel (US). METHODS: Forty patients with rectal cancer, who underwent laparoscopic TME with anal sphincter preservation from June 2005 to June 2007, were randomly divided into ultrasonic scalpel group and monopolar ES group, prospectively. White blood cells (WBC) were measured before and after operation, operative time, blood loss, pelvic volume of drainage, time of anal exhaust, visual analogue scales (VAS) and surgery-related complications were recorded. RESULTS: All the operations were successful; no one was converted to open procedure. No significant differences were observed in terms of preoperative and postoperative d 1 and d 3 WBC counts (P=0.493, P=0.375, P=0.559), operation time (P=0.235), blood loss (P=0.296), anal exhaust time (P=0.431), pelvic drainage volume and VAS in postoperative d 1 (P=0.431, P=0.426) and d 3 (P=0.844, P=0.617) between ES group and US group. The occurrence of surgery-related complications such as anastomotic leakage and wound infection was the same in the two groups. CONCLUSION: ES is a safe and feasible tool as same as US used in laparoscopic TME with anal sphincter preservation for rectal cancer on the basis of the skillful laparoscopic technique and the complete understanding of laparoscopic pelvic anatomy. Application of ES can not only reduce the operation costs but also benefit the popularization of laparoscopic operation for rectal cancer patients.

[Expression of epithelial cadherin in early gastric cancer and its correlation to lymph node micrometastasis and clinicopathologic features].

BACKGROUND & OBJECTIVE: Lymph node micrometastasis in early gastric cancer is being widely discussed. Cytokeratin (CK) staining is an important way to distinguish epithelial cancer cells. This study was to investigate the correlations of epithelial cadherin (E-cad) expression to lymph node micrometastasis, and clinicopathologic features of early gastric cancer, and to evaluate its clinical significance. METHODS: Morphology of 4522 lymph nodes from 162 patients with early gastric cancer was observed with HE staining and CK immunostaining. E-cad expression in 135 primary lesions of these patients was detected by immunohistochemistry. The correlations of E-cad expression to clinicopathologic features were analyzed. RESULTS: The detection rate of lymph node metastasis by CK staining was significantly higher than that by HE staining (26.5% vs. 6.8%, P<0.001). CK immunostaining detected 32 cases of lymph node micrometastasis which were missed by HE staining. Lymph node micrometastasis was frequently found in primary tumors with a diameter of more than 1.0 cm, in those that were poorly differentiated, deeply invaded (for example, to the submucosa), showed lymphatic or vascular invasion, and in those that showed loss of E-cad expression (P<0.05). The reduced expression rate of E-cad in primary tumor was 57.0%, closely correlated to lymph node micrometastasis. The 5-year survival rate was significantly lower in the patients with lymph node micrometastasis than in those without such metastasis (93.6% vs. 100%, P<0.01). CONCLUSION: Primary tumor more than 1.0 cm in diameter, poor differentiation, deep invasion, lymphatic or vascular invasion, and loss of E-cad expression are risk factors for lymph node metastasis in early gastric cancer.

[Clinical significance of micrometastasis in lymph nodes and microinvasion in primary lesion in submucosal gastric cancer].

OBJECTIVE: To clarify the clinicopathologic characteristics of micrometastasis in lymph nodes and microinvasion in primary lesion for the treatment options with regard to submucosal gastric cancer. METHODS: 1945 lymph nodes and 68 primary tumors resected from 79 patients with submucosal gastric cancer were examined. Two consecutive sections were prepared for simultaneous staining with HE and immunostaining with anti-cytokeratin antibody (CAM 5.2), respectively. RESULTS: The incidence of nodal involvement in 79 patients with submucosal gastric cancer was increased from 13% (10/79 patients) by HE staining to 34% (27/79 patients) by cytokeratin immunostaining. Micrometastasis in the lymph nodes were found in 17 of 69 patients (25%) with cancer-free nodes examined by HE staining. Microinvasion to the muscularis properia was found in 11 of 68 patients (16%) who were histologically diagnosed as submucosal gastric cancer. Survival analysis demonstrated a worse 5-year survival in the patients with micrometastasis in lymph nodes (82%) and with microinvasion to muscularis properia (73%). A higher incidence of nodal involvement was found in submucosal cancers of large size (> 2 cm; 43%), a depressed type (48%), lymphatic invasion (73%), and deeper submucosal invasion (submucosal 3; 53%). A higher incidence of microinvasion was found with the diffused-type carcinoma (33%). CONCLUSIONS: Cytokeratin immunostaining is useful for detecting micrometastasis and microinvasion in submucosal gastric cancer. Tumor size, microscopic type, lymphatic invasion, and the depth of submucosal invasion are strongly associated with lymph node involvement. Micrometastasis in lymph nodes and microinvasion in primary lesion indicate an unfavorable outcome of the patients with submucosal gastric cancer.

[A clinical analysis of 104 cases of acute pure and mixed organophosphate poisoning].

OBJECTIVE: To study the difference of the clinical manifestations between single and mixed acute organophosphate (OP) poisoning. METHODS: The clinical signs and symptoms, the activity of cholinesterase (ChE) in erythrocytes, plasma and whole blood, and the level of AST, CK, LDH and ALT were compared between a single OP poisoning group (Group S) and a mixed OP poisoning group (Group C). RESULTS: Group S and Group C compare with: (1) Symptoms and signs on arrival at hospital: Group C was found to have more cases showing, nausea and vomiting than group S with obvious difference (P < 0.05). (2) The rates of other symptoms and signs were of no significant difference between the 2 groups. The activity of cholinesterase of the 2 groups on arrival at hospital: Whole blood ChE < 0.30: 16 cases and 14 cases; > 0.30 approximately : 24 cases and 19 cases; 0.50 approximately 0.70: 14 cases and 17 cases; erythrocyte ChE < 0.30: 18 cases and 14 cases; > 0.30 approximately : 22 cases and 21 cases; 0.50 approximately 0.70: 14 cases and 15 cases; plasma ChE < 0.30: 28 cases and 25 cases; > 0.30 approximately : 10 cases and 12 cases; 0.50 approximately 0.70: 16 cases and 13 cases; chi(2) = 0.852, 1.444, 0.509. There was no obvious difference (P > 0.05). (3) Positive rates of serum biochemical parameters between the 2 groups within 72 hours after arrival at hospital: Group S AST 24 cases, ALT 18 cases, CK 42 cases, LDH 22 cases, Tbil 21 cases; Group C AST 20 cases, ALT 11 cases, CK 32 cases, LDH 18 cases, Tbil 17 cases. There was also no obvious difference (P > 0.05). (4) Positive rate of ECG: between the 2 group on arrival at hospital Group S 24 cases, Group C 19 cases. No obvious difference was shown (P > 0.05). (5) Fatality rates between the 2 groups: Group S 7.41% (4/54), Group C 6.00% (3/50), chi(2) = 0.082, P > 0.05. CONCLUSION: Acute mixed OP poisoning and single OP poisoning show no significant difference in clinical manifestations. The treatment measures for single OP poisoning also has good effect fo mixed OP poisoning.