Neoadjuvant Modified FOLFOX6 With or Without Radiation Versus Fluorouracil Plus Radiation for Locally Advanced Rectal Cancer: Final Results of the Chinese FOWARC Trial.

PURPOSE: In the multicenter, open-label, phase III FOWARC trial, modified infusional fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) plus radiotherapy resulted in a higher pathologic complete response rate than fluorouracil plus radiotherapy in Chinese patients with locally advanced rectal cancer. Here, we report the final results. METHODS: Adults ages 18 to 75 years with stage II/III rectal cancer were randomly assigned (1:1:1) to five cycles of infusional fluorouracil (leucovorin 400 mg/m2, fluorouracil 400 mg/m2, and fluorouracil 2.4 g/m2 over 48 hours) plus radiotherapy (46.0 to 50.4 Gy delivered in 23 to 25 fractions during cycles 2 to 4) followed by surgery and seven cycles of infusional fluorouracil, the same treatment plus intravenous oxaliplatin 85 mg/m2 on day 1 of each cycle (mFOLFOX6), or four to six cycles of mFOLFOX6 followed by surgery and six to eight cycles of mFOLFOX6. The primary end point was 3-year disease-free survival (DFS). RESULTS: In total, 495 patients were randomly assigned to treatment. After a median follow-up of 45.2 months, DFS events were reported in 46, 39, and 46 patients in the fluorouracil plus radiotherapy, mFOLFOX6 plus radiotherapy, and mFOLFOX6 arms. In each arm, the probability of 3-year DFS was 72.9%, 77.2%, and 73.5% (P = .709 by the log-rank test), the 3-year probability of local recurrence after R0/1 resection was 8.0%, 7.0%, and 8.3% (P = .873 by the log-rank test), and the 3-year overall survival rate was 91.3%, 89.1%, and 90.7% (P = .971 by log-rank test), respectively. CONCLUSION: mFOLFOX6, with or without radiation, did not significantly improve 3-year DFS versus fluorouracil with radiation in patients with locally advanced rectal cancer. No significant difference in outcomes was found between mFOLFOX6 without radiotherapy and fluorouracil with radiotherapy, which requires additional investigation of the role of radiotherapy in these regimens.

Modified FOLFOX6 With or Without Radiation Versus Fluorouracil and Leucovorin With Radiation in Neoadjuvant Treatment of Locally Advanced Rectal Cancer: Initial Results of the Chinese FOWARC Multicenter, Open-Label, Randomized Three-Arm Phase III Trial.

PURPOSE: Total mesorectal excision with fluorouracil-based preoperative chemoradiotherapy and postoperative chemotherapy is a standard treatment of locally advanced rectal cancer. This study investigated the addition of oxaliplatin with and without preoperative radiotherapy. METHODS: In this multicenter, open-label, phase III trial, we randomly assigned (1:1:1) Chinese adults (age 18 to 75 years) with locally advanced stage II/III rectal cancer to three treatments: five 2-week cycles of infusional fluorouracil (leucovorin 400 mg/m(2), fluorouracil 400 mg/m(2), and fluorouracil 2.4 g/m(2) over 48 h) plus radiotherapy (46.0 to 50.4 Gy delivered in 23 to 25 fractions during cycles 2 through 4) followed by surgery and seven cycles of infusional fluorouracil, the same treatment plus intravenous oxaliplatin 85 mg/m(2) on day 1 of each cycle (modified FOLFOX6 [mFOLFOX6]), or four to six cycles of mFOLFOX6 followed by surgery and six to eight cycles of mFOLFOX6. Random assignment was performed by using computer-generated block randomization codes. The primary end point was 3-year disease-free survival. Secondary end points of histopathologic response and toxicity are reported. RESULTS: A total of 495 patients were enrolled from June 2010 to February 2015; 475 were evaluable (fluorouracil-radiotherapy, n = 155; mFOLFOX6-radiotherapy, n = 157; mFOLFOX6, n = 163). In the fluorouracil-radiotherapy, mFOLFOX6-radiotherapy, and mFOLFOX6 groups, the rate of pathologic complete response (pCR) was 14.0%, 27.5%, and 6.6%, and downstaging (ypStage 0 to 1) was achieved by 37.1%, 56.4%, and 35.5% of patients, respectively. Higher toxicity and more postoperative complications were observed in patients who received radiotherapy. CONCLUSION: mFOLFOX6-based preoperative chemoradiotherapy results in a higher pCR rate than fluorouracil-based treatment. Perioperative mFOLFOX6 alone had inferior results and a lower pCR rate than chemoradiotherapy but led to a similar downstaging rate as fluorouracil-radiotherapy, with less toxicity and fewer postoperative complications.

[Laparoscopic-assisted modified Soave procedures for adult Hirschsprung disease].

OBJECTIVE: To evaluate the clinical value of laparoscopy-assisted modified Soave procedure for Hirschsprung disease in adults. METHODS: Twenty-eight patients with a preoperative diagnosis of Hirschsprung disease underwent laparoscopy-assisted modified Soave procedure between March 2005 and December 2009. Clinical data were retrospectively analyzed. RESULTS: There were no conversions to open surgery. The mean operative time was (165±12) minutes (range: 135-185 minutes). Estimated blood loss ranged from 50 to 250 ml, and no patients required intraoperative blood transfusion. Postoperative pathologic examination showed Hirschsprung diseases in 19 patients and Hirschsprung allied diseases in 9. Only two patients developed rectal cuff infection and three mild seepage. Other patients had no postoperative complications. The mean hospital stay was (17.5±1.0) days. No fecal incontinence or recurrent constipation occurred during follow-up. CONCLUSION: Laparoscopy- assisted modified Soave procedure is safe and effective for Hirschsprung disease.

[Effects of magnetic gemcitabine stealth nano-liposomes on the characteristics of breast cancer cell line MCF-7].

The magnetic responsibility and antitumor effect of magnetic gemcitabine stealth nano-liposomes (MGSL) on breast cancer cell line MCF-7 in vitro and in vivo was evaluated. The magnetic response and targeting effect of MGSL in vivo were investigated. Morphological feature and ultrastructure changes of apoptosis of MCF-7 cells were observed. The effect of MGSL on proliferation inhibitory rate of MCF-7 cells was measured with MTT method. The FCM analysis was carried out to examine the cell cycle distribution and cell apoptotic rate. The antitumor effect on human breast cancer xenografts in nude mice was also studied. MGSL was able to converge at the targeting tissue under tridimensional magnetic field and the gemcitabine concentration around it increased, while the amount of gemcitabine in other organs decreased, such as in kidneys and heart. MCF-7 cell line was sensitive to MGSL and the cytotoxity was correlated with the loaded drug dose. The effect of MGSL on apoptosis of MCF-7 was obvious and the rate of apoptosis was 51.62%. The growth speed of tumor in the group of MGSL (+) significantly slowed down than that of other groups. MGSL prepared by reverse-phase evaporation method met with the demand of targeted delivery system, and it might be an effective antitumor agent.

Exogenous PTEN gene induces apoptosis in breast carcinoma cell line MDA468.

The effects and mechanisms of exogenous phosphatase and tensin homolog deleted from chromosome ten (PTEN) gene on phosphatase activity-dependent apoptosis of breast cancer cell line MDA468 were investigated. PTEN gene packaged with lipofectin was transferred into breast cancer cell line MDA468 and parental MDA468 cells served as controls. RT-PCR and Western blot were done to detect the expression of target genes. The expression of phosphospecific protein kinase B (PKB/Akt) and focal adhesion kinase (FAK) protein stimulated by epidermal growth factor (EGF) was also detected. Apoptosis was determined by flow cytometry with a double-staining method using FITC-conjugated annexin V and PI. MDA468 cells transfected with PTEN gene could express PTEN mRNA and protein. PTEN decreased the phosphorylation level of AKT protein and down-regulated FAK protein expression in MDA468 stimulated by EGF. The apoptosis rate was 21.68%. PTEN induced breast cancer apoptosis phosphatase activity-dependently. The mechanism is possibly related with phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB)/AKT signaling pathway. Those results may provide new clues on the gene therapy in breast cancer.

[Efficacy and safety of adjuvant post-surgical therapy with imatinib in gastrointestinal stromal tumor patients with high risk of recurrence: interim analysis from a multicenter prospective clinical trial].

OBJECTIVE: To evaluate the efficacy and safety of postoperative adjuvant chemotherapy with imatinib in gastrointestinal stromal tumor(GIST) patients who had high risk of recurrence. METHODS: A prospective, open-label, multi-center trial conducted in sixteen teaching hospitals in China was carried out. The criteria of the enrolled patients included age more than 18 years old, CD117 positive GIST, tumor size more than 5 cm, pathological mitosis counts more than 5/50 HPF, and treatment beginning within 4 weeks after complete resection and with imatinib (400 mg, once a day) for at least 12 months. The 1, 3 year recurrence rates, disease free survival, overall survival rate and quality of life were evaluated. RESULTS: From Aug. 16th 2004 to Sep. 13th 2005, there were totally 74 patients screened and 57 patients (34 men, 23 women) enrolled in the imatinib treatment group. The primary tumors were located in the stomach in 50.9%, the small intestine in 38.6% and the colorectum in 10.5% of the cases. All the patients received radical resection. Until the cut-off date of interim analysis, there was no evidence of tumor relapse or metastasis in all patients and no death was reported either. Among the 57 enrolled patients with intention to treat(ITT), twelve patients finished the protocol (per protocol, PP). The disease free survival was (268.3 +/-120.2) d in ITT analysis, and (396.7+/-38.2) d in the PP analysis. The incidence of adverse effect was 44.4% . The score in quality of life showed no statistically significant difference between the baseline visit and the follow-up visits. CONCLUSION: Imatinib is a promising postoperative adjuvant chemotherapy in GISTs patients with high risk of recurrence, and the adverse effects are receivable.

Construction and expression of human PTEN tumor suppressor gene recombinant adenovirus vector.

The recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene was constructed by using AdEasy-1 system and its expression was detected in human breast cancer cell line MDA-MB-468. Human PTEN cDNA was cloned into adenovirus shuttle plasmid pAdTrack-CMV to generate a recombinant plasmid pAdTrack-CMV-PTEN, then homologeous recombination was carried out in the E. coli BJ5183 by contransforming linearized shuttle vector with adenovirus backbone plasmid pAdEasy-1. The newly recombined defective adenovirus vector Ad-PTEN containing green fluorescent protein (GFP) was packaged and propagated in 293 cells. After being purified by cesium chloride gradient centrifugation, the adenovirus was transfected into human breast cancer cell line MDA-MB-468 in vitro. The expression of PTEN mRNA and protein in infected human breast cancer cell line MDA-MB-468 was detected by RT-PCR and Western blot respectively. The recombinant defective adenovirus vector carrying PTEN gene was constructed successfully. The viral titer of purified adenovirus was 2. 5 X 10(10) pfu/mL, and about 70% breast cancer cells were infected with Ad-PTEN when multiplicity of infection (MOI) reached 50. The exogenous PTEN mRNA and protein were expressed in MDA-MB-468 cells infected with Ad-PTEN by RT-PCR and Western blot. The recombinant defective adenovirus vector of PTEN gene was constructed successfully using AdEasy-1 system rapidly, which paved a sound foundation for gene study of breast cancer.

Serum vascular endothelial growth factor-C and vascular endothelial growth factor level in patients with colorectal carcinoma and clinical significance.

Circulating vascular endothelial growth factor-C (VEGF-C) and vascular endothelial growth factor (VEGF) levels in patients with colorectal carcinoma were determined in order to assess their clinical significance as a diagnostic tool for monitoring lymph node metastasis. In 66 patients with colorectal carcinoma and 30 healthy controls, circulating VEGF-C and VEGF levels were assessed by using enzyme-linked immunosorbent assay (ELISA). Serum VEGF-C and VEGF levels were higher in patients with colorectal carcinoma than in healthy controls. Patients with lymph node metastasis had higher serum VEGF-C and VEGF levels than those without lymph node metastasis. The levels of VEGF-C and VEGF were higher in the invasion group than in the non-invasion group. Serum VEGF-C levels reached a sensitivity of 81% and a specificity of 76% with a cutoff value of 1438.0 pg/mL, whereas VEGF levels reached 72% sensitivity and 74% specificity at 240.2 pg/ mL. If 66 patients were divided into 4 groups according to the combined determination of VEGF-C and VEGF levels, the positive predictive value was 85.3%, the negative predictive value was 94.6%, and accuracy was 93.7%. It was suggested that circulating VEGF-C levels might provide additional information for distinguishing the absence from presence of lymph node metastasis in patients with colorectal carcinoma. The combined determination of VEGF-C and VEGF levels could be used as an important index for preoperatively clinical stage of colorectal carcinoma.

[Double sites short hairpin RNAs targeting epidermal growth factor receptor to promote colon cancer cells apoptosis and enhance 5-fluorouracil chemotherapy effect].

OBJECTIVE: To investigate the differences about RNA interference (RNAi) technique which focuses on single or multiple sites to suppress colon cancer LoVo cell line's epidermal growth factor receptor (EGFR) mRNA and protein expression, induce cell apoptosis and enhance 5-fluorouracil (5-FU) sensitivity. METHODS: The human colon cancer LoVo cells were transfected by liposome with pU6-EGFR-shRNA-1 and pU6-EGFR-shRNA-2 expressive vectors which were established by p Genesil-1 plasmid and EGFR short hairpin RNA (shRNA) synthesized in vitro, then were selected for 4 weeks by using G418. Five groups were selected for the study: Group 1: the normal cultured LoVo cells; Group 2: the negative control plasmid HK; Group 3: pU6-EGFR-shRNA-1 plasmid vector; Group 4: pU6-EGFR-shRNA-2 plasmid vector; Group 5: pU6-EGFR-shRNA-1 and pU6-EGFR-shRNA-2, half for each. The mRNA and protein expression were assessed using Real Time PCR and Western blot, the cell apoptosis was determined via flow cytometry, and the suppressive rate and IC(50) to LoVo cells by 5-FU of different concentrations and time points were carried out by using Cell Counting Kit-8 (CCK-8). RESULTS: Expression plasmids encoding shRNA were successfully established and transfected into the LoVo cells. In group 3, 4 and 5, the mRNA expression was decreased by (80.2 +/- 3.4)%, (81.3 +/- 2.8)% and (90.6 +/- 2.8)%, respectively, and protein expression was decreased by (74.1 +/- 4.0)%, (73.4 +/- 2.3)% and (90.4 +/- 3.3)%, respectively; meanwhile, cell apoptosis increased by (10.4 +/- 0.5)%, (10.1 +/- 0.4)% and (14.2 +/- 0.5)%, respectively. The IC(50) of 5-FU and cell suppressive rate analysis demonstrated that there were significant differences among group 5, groups 3 and 4, and groups 1 and 2, but there were no significant difference between group 1 and group 2, as well as group 3 and group 4. CONCLUSIONS: Both pU6-EGFR-shRNA-1 and pU6-EGFR-shRNA-2 were capable of suppressing EGFR expression of LoVo cells, and therefore promoting apoptosis and increasing the cell toxicity of 5-FU. The targeting double combined sites RNAi technique was significantly better than single site interference. The new therapeutic modalities in the treatment of human colon cancer are suggested by this study.

[Antisense RNA targeting survivin enhances the chemosensitivity of LOVO/Adr cells to taxotere].

OBJECTIVE: To investigate the ability of antisense RNA eukaryotic expression plasmid pcDNA3.0/survivin targeting survivin gene to inhibit survivin expression and enhance the sensitivity to taxotere in multidrug resistant colon carcinoma cell line LOVO/Adr. METHODS: The antisense RNA eukaryotic plasmid pcDNA3.0/survivin was transfected into LOVO/Adr cells by lipofectamine. The expression of survivin mRNA was measured using RT-PCR. After treated with taxotere, MTT assay and flow cytometry were used to evaluate the proliferation inhibition and apoptosis of LOVO/Adr cells. RESULTS: The expression of survivin mRNA in LOVO/Adr cells transfected with pcDNA3.0/survivin was down-regulated in a time- dependent manner. The inhibitory rate of taxotere (0.5 micromol/L) was (37.3 +/- 2.9)% in pcDNA3.0/survivin transfected cells, significantly higher than (21.9 +/- 2.3)% and (21.1 +/- 1.9)% in pcDNA3.0 transfected and untransfected control cells respectively (P< 0.01). The apoptosis rate of taxotere was (28.7 +/- 1.7)% in pcDNA3.0/survivin transfected cells,significantly higher than (13.4 +/- 1.6)% and (14.3 +/- 1.8)% in pcDNA3.0 transfected and untransfected cells respectively. CONCLUSION: The antisense RNA eukaryotic expression plasmid pcDNA3.0/survivin could down-regulate the expression of survivin gene and enhance the chemosensitivity of LOVO/Adr cells to taxotere, which may provide a novel therapy for colon carcinoma.

[Surgical treatment of massive rebleeding after gastrectomy for bleeding gastroduodenal ulcer].

OBJECTIVE: To summarize the reoperation experiences in treatment of massive rebleeding after subtotal gastrectomy for bleeding gastroduodenal ulcer. METHODS: From 1980 to 2002, clinical data of 26 cases with massive rebleeding after subtotal gastrectomy for bleeding gastrorenal ulcer were analyzed retrospectively. RESULTS: Preoperative gastroscopy was performed in 6 cases, intraoperative gastroscopy in 11, and preoperative superselective angiography in 2 cases. Eleven cases with left ulcer or post- bulb ulcer bleeding underwent resection of the left ulcer or longitudinal incision of the duodenal descending part and direct hemostasis. Thirteen cases with anastomotic stoma bleeding underwent local suture hemostasis or resection of the stoma plus Billroth II or Roux- en- Y gastrojejunostomy. Two cases with gastric bleeding received reexcision of the stomach remnant. Twenty- four cases (92.3% ) were cured and 2 cases (7.7% ) died of gastric bleeding. CONCLUSION: Preoperative superselective angiography and intraoperative gastroscopy are beneficial to clarify the bleeding position and causes for massive rebleeding after gastrectomy. It is very important to select proper operative method to prevent postoperative rebleeding.

Nitrite-derived nitric oxide by xanthine oxidoreductase protects the liver against ischemia-reperfusion injury.

BACKGROUND: It was demonstrated that xanthine oxidoreductase (XOR), during ischemia, catalyzes the formation of nitric oxide (NO) from nitrite (NO2-) and this NO2- -derived NO protects the isolated perfused rat heart against the damaging effects of ischemia-reperfusion (I/R) when conventional nitric oxide synthase (NOS)-dependent NO production is impaired. Liver is one of the organs with the highest XOR concentration. This study was designed to determine whether NO2- -derived NO by XOR protects liver against I/R injury in vivo. For its minute amounts and active reactivity, NO can not be detected directly in real time in vivo by this time. We have to prove the above hypothesis indirectly. METHODS: Wistar rats were pretreated with saline, NOS inhibitor L-NAME (10 mg/kg intravenously), XOR inhibitor allopurinol (1.5 mg/kg orally), L-NAME +allopurinol and NO scavenger carboxy-PTIO (0.6 mg/kg intravenously) respectively (12 animals per group). And then, they were subjected to total liver ischemia for 40 minutes followed by reperfusion. Blood samples and liver tissues were obtained for analysis after 3 hours of reperfusion. Survival was also investigated. RESULTS: Allopurinol-treated animals exhibited further increased serum alanine aminotransferase(ALT) levels and liver myeloperoxidase(MPO) activities, but further decreased liver adenosine triphosphate(ATP) stores after I/R compared to saline-treated counterparts (830.5+/-108.3 U/L, 56.5+/-11.0 U/mg protein and 1.93+/-0.47 mumol/g vs. 505.8+/-184.2 U/L, 41.5+/-10.2 U/mg protein and 3.05+/-0.55 micromol/g respectively, P < 0.01, P < 0.05 and P < 0.01 respectively). The hepatocyte injury was further exacerbated and the overall survival rate was significantly decreased after I/R in animals given by allopurinol compared to those pretreated by saline (P < 0.05). L-NAME and allopurinol co-treated animals exhibited more severe liver injury (P < 0.05 and P<0.01)and a further decreased overall survival rate (P < 0.05)compared to L-NAME or allopurinol alone-treated counterparts, but they were not different from carboxy-PTIO treated animals (P > 0.05). CONCLUSION: NO2- -derived NO by XOR in the hypoxic and acidic environment induced by hepatic I/R protects the liver against I/R injury in vivo.

[Construction of PTEN eukaryotic expression plasmid and its effects on breast carcinoma cell line MDA468].

OBJECTIVE: To investigate the effects of exogenous wild PTEN gene stably transfection on growth of breast cancer cells in vitro. METHODS: At first, a recombinant eukaryotic expression plasmid pcDNA3.1-PTEN was constructed. Human breast cancer cell line MDA468 was transfected with pcDNA3.1-PTEN or mock transfected plasmid pcDNA3.1(-) with lipofectamine. RT-PCR, immunohistochemical staining and Western blot were used to determine target gene expression. Cell viability was tested by MTT assay. Apoptosis was determined by flow cytometry with a double-staining method using FITC-conjugated annexin V and PI. RESULTS: The PTEN stably transfected cells demonstrated the integration of the exogenous target gene and corresponding mRNA and protein over-expression. There was a significant decline in cell viability of pcDNA3.1-PTEN transfected MDA468 cells in comparison with the mock-transfected ones (P < 0.01). The PTEN-trasfected MDA468 cells also showed an increase in the rate of apoptosis, compared with parental and mock-trasfected cells (P < 0.001). CONCLUSION: Stable expression of exogenous PTEN can suppress the malignant phenotypes of the human breast cancer cell line MDA468.

Gender differences in hepatic ischemic reperfusion injury in rats are associated with endothelial cell nitric oxide synthase-derived nitric oxide.

AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated with endothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO). METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-alpha levels, liver tissue malondialdehyde (MDA) content, and severity of hepatic I/R injury. RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7+/-11.0 micromol/L vs 45.3+/-10.1 micromol/L, P<0.01). Although serum NO levels decreased significantly after hepatic I/R (P<0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8+/-8.6 micromol/L vs 23.8+/-4.7 micromol/L, P<0.01). Serum ALT and TNF-alpha levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5+/-46.4 U/L, 0.99+/-0.11 microg/L and 0.57+/-0.10 micromol/g vs 668.7+/-78.7 U/L, 1.71+/-0.18 microg/L and 0.86+/-0.11 micromol/g, respectively, P<0.01). I/R induced significant injury to the liver both in M and F groups (P<0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P<0.05 and P<0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P<0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-beta-estradiol (E2) (M+E2 group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-alpha levels, and liver tissue MDA content after I/R (P<0.01). The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E2 group than in M group (P<0.01 and P<0.05). The NOS inhibitor N(w) -nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats. CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOS-derived NO.

[Exogenous PTEN gene induces apoptosis in breast cancer cells].

OBJECTIVE: To investigate the effects of exogenous PTEN gene on apoptosis of breast cancer cells. METHODS: Human breast cancer cells of the line MDA468 were cultured. Recombinant plasmid pcDNA3.1-PTEN was constructed and transfected into the breast cancer cells with the lipofectAMINE 2000 transfection technique. Parental MDA468 cells and parental MDA468 cells transfected with blank vector pcDNA3.1(-) were used as control groups. RT-PCR was used to detect the expression of the PTEN mRNA and Western blotting was used to determine the expression of PTEN protein. Epithelial growth factor (EGF) was added into the cultures of MDA468 cells transfected with pcDNA3.1-PTEN or blank vector. Then Western blotting was used to detect the expression of phosphospecific protein kinase B (PKB/Akt) and focal adhesion kinase (FAK) protein stimulated by EGF. The aapoptosis of the MDA468 cells was determined by flow cytometry with the double-staining method using FITC-conjugated annexin V and PI. RESULTS: Expressions of PTEN mRNA and protein were shown in the MDA468 cells transfected with pcDNA3.1-PTEN by RT-PCR and Western blotting. Both the expression of p-AKT and that of p-FAK were down-regulated in the MDA468 cells transfected with pcDNA3.1-PTEN in comparison with those in the control cells. The apoptotic rate of the MDA468 cells transfected with PCDNA3.1-PTEN was 21.68%, significantly higher than those of the blank control cells (1.17%) and pcDNA3.1(-)-transfected cells (3.55%, both P < 0.01). CONCLUSION: Exogenous PTEN suppress the growth of human breast cancer cell and induces apoptosis by phosphatase activity, which provides a new clue to gene therapy for breast cancer.

Involvement of M3 cholinergic receptor signal transduction pathway in regulation of the expression of chemokine MOB-1, MCP-1 genes in pancreatic acinar cells.

Whether M3 cholinergic receptor signal transduction pathway is involved in regulation of the activation of NF-kappaB and the expression of chemokine MOB-1, MCP-lgenes in pancreatic acinar cells was investigated. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, atropine and PDTC in vitro. The MOB-1 and MCP-1 mRNA expression was detected by using RT-PCR. The activation of NF-kappaB was monitored by using electrophoretic mobility shift assay. The results showed that as compared with control group, M3 cholinergic receptor agonist (10(-3) mol/L, 10(-4) mol/L carbachol) could induce a concentration-dependent and time-dependent increase in the expression of MOB-1, MCP-1 mRNA in pancreatic acinar cells. After treatment with 10(-3) mol/L carbachol for 2 h, the expression of MOB-1, MCP-1 mRNA was strongest. The activity of NF-kappaB in pancreatic acinar cells was significantly increased (P<0.01) after treated with M3 cholinergic receptor agonist (10(-3) mol/L carbachol) in vitro for 30 min. Either M3 cholinergic receptor antagonist (10(-5) mol/L atropine) or NF-kappaB inhibitor (10(-2) mol/L PDTC) could obviously inhibit the activation of NF-kappaB and the chemokine MOB-1, MCP-1 mRNA expression induced by carbachol (P<0.05). This inhibitory effect was significantly increased by atropine plus PDTC (P<0.01). The results of these studies indicated that M3 cholinergic receptor signal transduction pathway was likely involved in regulation of the expression of chemokine MOB-1 and MCP-lgenes in pancreatic acinar cells in vitro through the activation of NF-kappaB.

Tumor type M2 pyruvate kinase expression in gastric cancer, colorectal cancer and controls.

AIM: Tumor formation is generally linked to an expansion of glycolytic phosphometabolite pools and aerobic glycolytic flux rates. To achieve this, tumor cells generally overexpress a special glycolytic isoenzyme, termed pyruvate kinase type M(2). The present study was designed to evaluate the use of a new tumor marker, tumor M(2)-PK, in discriminating gastrointestinal cancer patients from healthy controls, and to compare with the reference tumor markers CEA and CA72-4. METHODS: The concentration of tumor M(2)-PK in body fluids could be quantitatively determined by a commercially available enzyme-linked immunosorbent assay (ELISA)-kit (ScheBo Tech, Giessen, Germany). By using this kit, the tumor M(2)-PK concentration was measured in EDTA-plasma of 108 patients. For the healthy blood donors a cut-off value of 15 U/mL was evaluated, which corresponded to 90% specificity. Overall 108 patients were included in this study, 54 patients had a histological confirmed gastric cancer, 54 patients colorectal cancer, and 20 healthy volunteers served as controls. RESULTS: The cut-off value to discriminate patients from controls was established at 15 U/mL for tumor M(2)-PK. The mean tumor M(2)-PK concentration of gastric cancer was 26.937 U/mL. According to the TNM stage system, the mean tumor M(2)-PK concentration of stage I was 16.324 U/mL, of stage II 15.290 U/mL, of stage III 30.289 U/mL, of stage IV 127.31 U/mL, of non-metastasis 12.854 U/mL and of metastasis 35.711 U/mL. The mean Tumor M(2)-PK concentration of colorectal cancer was 30.588 U/mL. According to the Dukes stage system, the mean tumor M(2)-PK concentration of Dukes A was 16.638 U/mL, of Dukes B 22.070 U/mL, and of Dukes C 48.024 U/ml, of non-metastasis 19.501 U/mL, of metastasis 49.437 U/mL. The mean tumor M(2)-PK concentration allowed a significant discrimination of colorectal cancers (30.588 U/mL) from controls (10.965 U/mL) (P<0.01), and gastric cancer (26.937 U/mL) from controls (10.965 U/mL) (P<0.05). The overall sensitivity of tumor M(2)-PK for colorectal cancer was 68.52%, while that of CEA was 43.12%. In gastric cancer, tumor M(2)-PK showed a high sensitivity of 50.47%, while CA72-4 showed a sensitivity of 35.37%. CONCLUSION: Tumor M(2)-PK has a higher sensitivity than markers CEA and CA72-4, and is a valuable tumor marker for the detection of gastrointestinal cancer.

Expression of vascular endothelial growth factor C and its correlation with lymph node metastasis in colorectal carcinoma.

To study the expression of vascular endothelial growth factor C (VEGF-C) in colorectal carcinoma and its relationship with lymph node metastasis, the expression of VEGF-C protein in colorectal carcinoma tissues obtained from 94 patients who underwent radical resection was immunohistochemically detected. Meanwhile, the expression of VEGF-C mRNA in 4 colorectal carcinoma cell lines was examined by reverse transcription polymerase chain reaction (RT-PCR). VEGF-C protein was found to be expressed in 53.2% of patients. The expression was more frequently detected in tumors with lymph node metastasis than in those without metastasis (P<0.01), and there was significant correlation between its expression and lymphatic invasion, TNM stage (P<0.01). However, no significant correlation was found between its expression and the age, gender, tumor location, depth of invasion and vascular invasion. 2 of the 4 colorectal carcinoma cell lines, including LoVo and LoVo-5FU, expressed VEGF-C mRNA. The expression of VEGF-C is closely related to lymph node metastasis, and it might take part in the tumor lymphangiogenesis.

[Relationship between estradiol and the mitogenic activated protein kinase signal transduction pathway].

OBJECTIVE: To discuss the relationship between estradiol and the mitogenic activated protein kinase signal transduction pathway and the expression of the MAPK in the MCF-7 breast cancer cell-line. METHODS: Epithelial growth factor (EGF) and different concentration of estradiol to induce the expression of phosphospecific ERK1/2 (pERK1/2) in MCF-7 cell line was used and the expression of pERK1/2 with western-blotting was detected. Then antiestrogen ICI 182780 and MAPK inhibitor PD98059 to inhibit the expression of pERK1/2 was used. The cell cycle of MCF-7 was detected by FACS. RESULTS: EGF could significantly induce the expression of pERK1/2. Estradiol could also induce the expression of pERK1/2, but the intensity was less than the induction of EGF. The percentage of cells in the G(2)/M cell cycle after estradiol induction increased (18.38%) compared to the control group (10.52%) (P < 0.05). CONCLUSIONS: MAPK is an important regulatory signal in breast cancer. Its measurement in breast cancer tissues provides information about the degree of activation of various growth factor pathways. This molecule may also provide a molecular target for compounds designed to block cell proliferation.