Effects of propofol on invasion and migration of human gastric cancer SGC-7901 cells

AIM: To investigate the effects of propofol on invasion and migration of gastric cancer cell line SGC-7901. METHODS: Cultured gastric cancer cell line SGC-7901 was randomly divided into 4 groups, and then diffe-rent concentrations (1, 3, 5 and 7 mg/L) of propofol were added and incubated for 24 h. The cell viability was measured by MTT assay. The invasion and migration abilities of the SGC-7901 cells were detected by Transwell assay and wound-healing assay. The expression of cysteine-rich angiogenic inducer 61 (CYR61), CD44v6 and matrix metalloproteinase-7 (MMP-7) in the SGC-7901 cells were examined by immunocytochemistry and Western blot.RESULTS: Propofol at 5 mg/L does not affect the viability of SGC-7901 cells, whereas significantly suppresses the invasion and migration abilities, and down-regulates the expression of CD44v6 and MMP-7 (P<0.05). CONCLUSION: The decreased invasion and migration abilities of SGC-7901 cells were partly due to the inhibition of CD44v6 and MMP-7 expression.     

Effect of NS-398 on invasion of colon cancer HT-29 cells in vitro and its regulation by CD44v6 and nm23-H1 genes

AIM: To study the anti-invasive effect of NS-398 on colon cancer cell line HT-29 in vitro an its regulation by CD44v6 and nm23-H1 genes. METHODS: Flow cytometry was used to detect the expression of COX-2 and CD44v6 in HT-29 cells. MTT was used for cell survival rate tests. The modified Boyden chamber model was used for quantitative invasion assay. RT-PCR was used to detect the expression of nm23-H1 mRNA. RESULTS: Flow cytometry analysis showed that COX-2 was positive in HT-29 cells. NS-398 had significant inhibitory effects on invasion of HT-29 cells, which had no relation with its cytotoxicity. NS-398 down-regulated the expression of CD44v6 and up-regulated the expression of nm23-H1 mRNA. CONCLUSION: NS-398 has an anti-invasive effect on HT-29 cells in vitro. Down-regulation of CD44v6 and up-regulation of nm23-H1 may be its underlying mechanisms.     

Effects of integrin αvβ6 on endo-exocytotic cycle of integrin αvβ5 in colon cancer cells

AIM: To investigate the effects of integrin αvβ6 on the endo-exocytotic cycle of integrin αvβ5 in colon cancer cells. METHODS: The expression of integrin αvβ6 and αvβ5 in SW480 cells, SW480 wild-type β6 cells and SW480 mock cells was detected by Western blotting. The trafficking of integrin αvβ6 and αvβ5 was examined by endocytosis assay, exocytosis assay and capture-ELISA. The adhesive and migration abilities of these 3 cell lines towards fibronectin or vitronectin were measured by cell adhesion assay and cell migration assay. RESULTS: The expression of integrin αv and β5 subunits was similar in these 3 cell lines (P>0.05), while the expression of integrin β6 subunit in SW480 wild-type β6 cells was much higher than that in the other 2 cell lines (P<0.05). The transfection of integrin β6 subunit into SW480 cells was able to slow down the endocytosis and exocytosis of integrin αvβ5, and subsequently inhibited the cellular adhesion and migration abilities towards vitronectin. CONCLUSION: Integrin αvβ6 and αvβ5 share the same αv subunit. In the process of endocytosis and exocytosis, there might be some competitive relationship between these 2 integrin isoforms. Compared with integrin αvβ5, integrin αvβ6 has the priority to get into the trafficking process, and it has subsequent effects on the adhesion and migration of colon cancer cells.     

Therapeutic effect of MCP-1 mediated macrophages on ovarian epithelial carcinoma

AIM: To investigate the therapeutic effect of MCP-1 mediated macrophages on ovarian epithelial carcinoma and its mechanisms.METHODS: Retorviral expression vectors pLXSN/MCP-1 was transfected into the packaging cell line PA317 by lipofectin-mediated gene transfer system. The virus particles containing MCP-1 gene were collected to infect NuTu-19. RT-PCR and Boyden Chamber were used to confirm the expression of MCP-1. Rat Fischer344 spleen macrophages were isolated. MTT method was applied to investigate the tumoricidal effect of macrophages. The survival time of the intraperitoneal disseminating ovarian cancer animal model was observed, and flow cytometry method was applied to analyze the expression of CD25 or CD44v6, and then the anti-tumor mechanisms of gene modified tumor cell lines were discussed. RESULTS: Stable MCP-1 expression in the cell line NuTu-19/MCP-1 possessed the chemotatic activity. The maximum killing ratio of macrophages on NuTu-19/MCP-1 cells was 28%. In the animal models immunized by MCP-1 expressing cells, prolonged survival time was showed which had statistical significance compared with that in the control group (P<0.05). The expression rate of CD25 (25.82%) in the NuTu-19/MCP-1 cells was higher than that in NuTu-19/neo cells (8.73%). The expression of CD44v6 in NuTu-19/MCP-1 cells was significantly lower than that in control NuTu-19/neo cells. CONCLUSION: MCP-1 mediates macrophages and suppresses the growth of NuTu-19. MCP-1 gene modified tumor cells can induce anti-tumor immunity. This strategy would be used as a promising approach for the treatment of ovarian cancer.     

Sensitivity of different human colorectal tumor cell lines to commonly used chemotherapeutic drugs in vitro

AIM: To observe the antitumor effect of 5 commonly used chemotherapeutic drugs on 11 human colorectal cancer cell lines in vitro. METHODS: CCK-8 method was used to determine the growth inhibitory effects of 5 antitumor drugs, which were expressed as the half growth inhibitory concentration (IC50) and sensitivity index IC50/PPC (peak plasma concentration) on 11 human colorectal cancer cell lines. The expression variations of heat-shock protein 27 (HSP27) and HSP70 at protein levels in human colorectal tumor cell lines treated with different chemotherapeutic drugs were observed by Western blotting. RESULTS: All the 11 colorectal cancer cell lines were sensitive to 5-fluorouracil (5-FU) and oxaliplatin (OHP) without drug resistant. Five colorectal cancer cell lines were sensitive to mitomycin (MMC), while the other 6 cell lines were moderately sensitive. Ten colorectal cancer cell lines except SW1116 were sensitive to docetaxel (DXL), while SW1116 cells were resistant to DXL. Nine colorectal cancer cell lines except LS174T and SW1116 were moderately sensitive to irinotecan (IFL), and SW1116 cells were also resistant to IFL, while LS174T cells were sensitive to IFL. After treated with the antitumor drugs, HSP27 was up-regulated in HCT116 cells and SW480 cells, while the expression of HSP70 didnt change. CONCLUSION: LS174T cells are multidrug-sensitive, while SW1116 cells are multidrug-resistant. 5-FU and OHP are the wide-spectrum anti-colorectal cancer drugs. Determining the sensitivity to chemotherapeutic drugs and the expression level of HSP27 can improve the accuracy in drug selection.     

Effects of αvβ6 integrin-mediated cell adhesion on 5-fluorouracil induced apoptosis in human colon carcinoma cell lines

AIM: To investigate the effects of αvβ6 integrin-mediated cell adhesion on 5-fluorouracil (5-FU) induced apoptosis in colon carcinoma cell lines.METHODS: The expression of the αvβ6 integrin in colon carcinoma cell lines HT-29 and WiDr cells was analyzed by flow cytometry. The apoptosis induced by 5-FU and the effects of αvβ6 integrin-mediated cell adhesion on 5-FU induced cell apoptosis were measured by enzyme-linked immunosorbent assay (ELISA) method and acridine orange-ethidium bromide (AO-EB) double fluorescent dye staining.RESULTS: Both the colon carcinoma cell lines HT-29 and WiDr cells expressed the αvβ6 integrin. The percentages of HT-29 and WiDr cells expression were 80.82% and 82.96%. 5-FU induced the apoptosis of colon carcinoma cell lines HT-29 and WiDr. The result of ELISA method displayed that enrichment factor (EF) of HT-29 and WiDr cells planted on fibronectin (FN)-ligand of αvβ6 integrin was lower significantly than the EF of HT-29 and WiDr cells planted on non-integrin ligand polylisin (1.11±0.04 vs 3.68±0.03, 1.09±0.02 vs 3.72±0.02, P<0.01) after cultured in medium containing 20 mg/L 5-FU for 48 h. When HT-29 and WiDr cells preincubated with αvβ6 integrin blocking antibody were planted on FN again, the EF of HT-29 and WiDr cells was higher significantly than those directly planted on FN without being blocked by αvβ6 integrin antibody (2.12±0.04 vs 1.11±0.04, 2.14±0.03 vs 1.09±0.02, P<0.01). The AO-EB double fluorescent dye staining displayed that the apoptosis percents of HT-29 and WiDr cells planting on FN were (5.6±1.1)% and (5.3±0.7)%, which were lower significantly than those planting on polylisin (37.0±1.4)%, (38.5±0.9)%, P<0.01. When HT-29 and WiDr cells preincubated with αvβ6 integrin blocking antibody were planted on FN again the percents of HT-29 and WiDr cells apoptosis were (19.5±1.2)% and (20.0±0.7)%, which increased significantly compared with those directly planting on FN without being blocked by αvβ6 integrin antibody (P<0.01). CONCLUSION: Colon carcinoma cell lines HT-29 and WiDr cells expressed αvβ6 integrin. The cell adhesion with FN mediated by αvβ6 integrin inhibits 5-FU-induced colon carcinoma cell apoptosis. The results suggest that cell adhesion may enhance drug resistance in colon carcinoma cell lines through inhibiting the cell apoptosis.     

Effect of berberine on the adhesion between human umbilical vein endothelial cells and human pulmonary carcinoma cells

AIM: To study the mechanism of berberine on the adhesion between human pulmonary carcinoma cells (PG cells) and HUVECs. METHODS: The effect of berberine (2.5-40 mg/L) on the proliferation of HUVECs was detected by MTT method. Further, PG cells were treated with berberine at doses of 2.5, 5, 10 mg/L for 6, 12, 24 h. The adhesion between PG cells and HUVECs was determined by rose bengal staining. The expression of CD44s on PG cells were determined by fluorescence antibody staining. Fluorescence anisotropy imaging system was used to assay the fluidity of PG cell membrane. RESULTS: Berberine at concentrations of 2.5, 5, 10 mg/L were the safety doses to the proliferation of HUVECs treated for 6, 12, 24 h. Berberine inhibited the adhesion between PG cells and HUVECs significantly in a dose-dependent manner (P<0.05 or P<0.01). Meanwhile, berberine increased the expression of CD44s on PG cells (P<0.05 or P<0.01). Berberine decreased the fluidity of PG cell membrane in a dose-dependent manner after 24 h incubation. CONCLUSION: Berberine inhibits the adhesion between PG cells and HUVECs by regulating the expression of adhesion molecules and the fluidity of cell membrane on PG cells.     

Expression of adhesion molecules in hepatocellurlar carcinoma and its clinical significance

AIM: To investigate the expression of adhesion molecules in hepatocellular carcinoma (HCC), and analyze its clinical significance. METHODS: The expressions of adhesion molecules of tumor tissues of 64 cases and adjacent tissues of 12 cases of HCC were detected with RT-PCR. RESULTS: ①The expression rates of E-cadherin, ICAM-1, CD44, CD44V, α₅, β₁ were 90.62%, 93.75%, 50.00%, 96.88%, 100%, 100%, respectively, and there was a significant difference between CD44 and other adhesion molecules. ②The expression level of E-cadherin, ICAM-1, CD44, CD_44V, α₅,β₁ in liver cancer tissues were 1.24±0.54, 0.96±0.37, 0.62±0.73, 0.86±0.33, 0.97±0.49, 1.41±0.24, respectively, and there was a significant difference between CD44 and E-cadherin, β₁. ③The expression level of E-cadherin and CD44 mRNA declined as HCC stage become higher, and there was a statistical difference in the expression level of CD44 mRNA between Ⅰ-Ⅱ stage and Ⅳ stage. The expression level of ICAM-1, α₅, β₁ had a trend to rise as HCC stage become higher, and there was a statistical difference in the expression level of ICAM-1 between Ⅰ-Ⅱ stage and Ⅳ stage. ④The expression level of ICAM-1,CD_44V, α₅, β₁ had positive correlation with tumor volume, tumor nodules, tumor metastasis, and had negative correlation with tumor encapsulation. E-cadherin and CD44 had negative correlation with tumor volume, tumor nodules, tumor metastasis, and had positive correlation with tumor encapsulation. All showed no significant correlation with the level of AFP , the degree of cirrhosis and the function of liver. CONCLUSION: There was a significant difference in the expression level of adhesion molecule mRNA in HCC, and their expression had Spearman correlation with each other. The expression level of adhesion molecule mRNA is associated with tumor volume, tumor nodules and tumor metastasis.     

Effect of miR-375 on viability,cell cycle and apoptosis of colon cancer HCT116 cells

AIM: To investigate the effect of microRNA-375 (miR-375) on the viability, cell cycle and apoptosis of HCT116 cells.METHODS: The expression of miR-375 in different colorectal cancer cell lines was detected by real-time PCR. The miR-375 mimics was transfected into HCT116 cells by Lipofectamine^TM 2000. The mRNA expression of miR-375 and AEG-1 was detected by real-time PCR. The HCT116 cell viability was detected by MTT assay. The changes of apoptosis and cell cycle distribution were analyzed by flow cytometry.RESULTS: Real-time PCR showed that miR-375 expression was the lowest in HCT116 among 4 colorectal cancer cell lines. The expression level of miR-375 significantly increased in miR-375 mimics group compared with that in the negative control group. The high expression level of miR-375 significantly inhibited the mRNA expression of AEG-1. After transfection with miR-375 mimics, the cell viability was inhibited, the apoptotic rate was increased, the proportion of G₁-stage cells was increased, and the proportion of S-stage cells was decreased.CONCLUSION: miR-375 inhibits the viability, mediates the cell cycle arrest and promotes the apoptosis of colon cancer HCT116 cells. miR-375 may act as a tumor suppressor in colorectal cancer by inhibiting AEG-1.     

Effect of curcumin on expression of p21 and CD44V6 in human breast cancer xenografts

AIM:To study the effect of curcumin on the expression of p21 and CD44V₆ in breast carcinoma in nude mice.METHODS:Nude mice were xenografted with human breast cancer cell line MCF-7 and randomly divided into 2 groups (n=4 in each group): control group and curcumin group. In latent period,the percentage of tumor development was observed. Tumors were measured and the surface areas were calculated. RT-PCR was performed to detect the expression level of cyclin D1,p21 and CD44V₆ mRNA. RESULTS:The tumor surface areas in the curcumin group were significantly lower than those in control group. In curcumin treatment group,the expression of p21 was up-regulated while cyclin D1 was nearly not changed. The expression of CD44V₆ was significantly down-regulated in curcumin group.CONCLUSION:Curcumin inhibits the expression of CD44V₆ and up-regulates the expression of p21 in nude mice bearing human breast cancer cell line MCF-7.     

Breast cancer stem cells cultured without insulin and effect of estrogen induction

AIM:To determine whether suspension culture medium without insulin can be used to feed breast cancer tumorsphere, or not. METHODS:MCF7 cells were used to build tumorsphere. The morphological changes, CD44+ CD24- expression, aldehyde dehydrogenase 1 (ALDH1) expression and multiple division ability were measured to identify the breast cancer stem cells and to detect the function of 17β-estradiol (E2β) in tumorsphere of MCF7 cells. RESULTS:The tumorshere, each containing 30 to 60 cells, was obtained by the method of insulin-removal suspension culture. These cells were cytokeratin 18 and CD10 proteins positive, and the number of CD44+ CD24- cells and ALDH1 protein expression were significantly higher than the adherent cultured cells (P<0.05). Using 10-10 mol/L E2β to treat the tumorshere for 7 d, the tumor cell number and volume were significantly increased. Using 10-10 mol/L E2β to treat the tumorshere for 24 h, the CD44+ CD24-cells and ALDH1 protein expression were significantly higher than those in non-treatment group (P<0.05). CONCLUSION: Suspension culture medium without insulin can be used to feed breast cancer tumorsphere. These tumorsphere could be used as a model to determine the function of E2β in breast cancer stem cell research.     

Transfer of siRNA against CD73 suppresses human breast cancer cell line MB-MDA-231 adhesion to extracellular matrix

AIM:To study the effect of CD73 on breast cancer cell line MB-MDA-231 adhesion to extracellular matrix.METHODS: ① CD73 siRNA plasmid was constructed and transfected into MB-MDA-231 cells by lipofectamine 2000.② The transfection efficiency was analyzed by flow cytometry using eGFP as a marker gene.Stable transfected MB-MDA-231 cells were selected using G418.③ RT-PCR and Western blotting analysis of CD73 expression in MB-MDA-231 cells was performed.④ The effects of CD73 on MB-MDA-231 cells adhesion to extrace...     

Up-regulation of microRNA-187* inhibits proliferation of human colon cancer cell line HCT116

AIM:To investigate the expression of microRNA-187* (miR-187*) in human colon cancer cell lines and normal colon tissues, and to determine the effects of miR-187* up-regulation on the proliferation and cell cycle of human colon cancer cell line HCT116. METHODS:The expression profiling of miRNAs in 3 colorectal adenocarcinoma samples and their matched normal tissue samples was performed using miRNA microarray chip. Total RNA was isolated from 8 colon cancer cell lines and 10 normal colon tissues. The miR-187* level was detected by Taqman real-time RT-PCR. B-cell-specific Moloney murine leukemia virus integration site 1 (BMI-1), the possible target of miR-187*, was also detected. Synthetic miR-187* mimics were transfected into HCT116 cell line by LipofectamineTM 2000. The mRNA expression of miR-187* and BMI-1 in HCT116 cell line was measured by real-time RT-PCR. Cell growth and cell cycle were assayed by MTS method and flow cytometry. RESULTS:miR-187* was found to be differentially expressed between colorectal adenocarcinoma and normal tissues. The expression of miR-187* in 8 colon cancer cell lines was down-regulated, while BMI-1 mRNA was up-regulated. Compared with blank control group, miR-187* expression was remarkably increased after transfection with miR-187* mimics, and ectopic expression of miR-187* significantly inhibited the mRNA expression of BMI-1. The cell growth was inhibited in miR-187* mimics group, and proliferating cell nuclear antigen (PCNA) mRNA expression was decreased. The cells at G2/M phase in miR-187* mimics group were significantly increased. CONCLUSION: miR-187* is down-regulated in human colon cancer cell lines. Up-regulation of miR-187* not only inhibits the proliferation but also influence the cell cycle of HCT116 cells, which might act as a tumor suppressor in colorectal cancer by inhibiting the expression of BMI-1.     

Expression of the novel serine protease SNC19 in different kinds of cells lines and its effects on cellular biological behaviors

AIM: To investigate the physiological function of the novel serine protease SNC19 protein and its possible role in cancer invasion and metastasis. METHODS: Monoclonal antibodies directly against SNC19 extracellular domain was prepared. The protein and SNC19 mRNA expression were determined in different kinds of cell lines respectively by Western blot and Northern blot analysis. Cellular migration and adhesion abilities were assayed by monoclonal antibody blocking method. RESULTS: Western blot analysis showed there were two bands of SNC19 protein in BCAP37, COLO205, SW480 cells at about 120 kD and 60 kD while only one band in SW620 cells at 60 kD; Northern blots showed a approximate 3.4-kilobase fragment appearing in most epithelial-derived cell lines with this only form and high levels but no detection was obtained in OV, TCA8113, KB and SGC7901 cells. In antibody blocking experiments, the migration of SW480 cells was significantly inhibited compared with the control and the abilities of SW480/SW480, SW480/NIH3T3 adhesion increased at the beginning of the experiments, but the difference reduced along with the time passed.CONCLUSION: SNC19 protein is closely related with cellular homogeneous and heterogeneous adhesion as well as cellular motility. As a novel serine protease, it may participate both in physiological and pathological processes, such as cell migration, tissue remodeling and cancer invasion and metastasis.     

Expression and clinical significance of chemokine receptor CXCR6 in primary colorectal cancer

AIM: To investigate the expression of chemokine receptor CXCR6 in primary colorectal cancer and determine the association between CXCR6 expression and synchronous liver metastasis/prognosis. METHODS: The colorectal cancer tissues from 143 patients were collected from August 2004 to December 2008 in the First Affiliated Hospital, Sun Yat-sen University. Twenty-night cases of the adjacent normal colorectal tissues were enrolled as controls. The expression of CXCR6 was detected by immunohistochemistry and the mean intergrated absorbance ( mIA ) was calculated by Image-Pro Plus 6.0 software. The relationship between CXCR6 expression and synchronous liver metastasis/prognosis was analyzed. RESULTS: The CXCR6 staining was mainly positive in colorectal cancer tissues but not in adjacent normal colorectal tissues. The mIA of CXCR6 in colorectal cancer was 1.54±0.04 (range: 0.41~2.84), and was 1.63±0.05 and 1.41±0.08 (P<0.05) in the cases with (n=83) or without (n=60) synchronous liver metastasis, respectively. According to the mean mIA of CXCR6 (1.54), the cases was divided into high CXCR6 group (mIA≥1.54) and low CXCR6 group ( mIA <1.54). The overall survival rate in high CXCR6 group was significantly lower than that in low CXCR6 group (P<0.05). In multivariate Cox regression models, age (P<0.05), lymph node metastasis (P<0.05) and synchronous liver metastasis (P<0.01) but not CXCR6 were identified as independent risk factors for poor outcome. In subgroup analysis, high CXCR6 expression was associated with poorer survival in the patients with stage I~III colorectal cancer (P<0.01) but not those with synchronous liver metastasis (P>0.05).CONCLUSION: CXCR6 in primary colorectal cancer tissues is associated with liver metastasis. It may become a potential target for the treatment of colorectal cancer liver metastasis.     

Serum sCD44s and sCD44v6 levels in breast cancer patients

AIM: To explore the clinical significance of detecting sCD44s and sCD44v6 in breast carcinoma. METHODS: Levels of serum soluble CD44 standard (sCD44s) and CD44 variant 6(sCD44v6) were detected by ELISA in 38 cases of breast cancer, 15 cases of benign breast diseases and 40 normal controls. RESULTS: The serum levels of sCD44s and sCD44v6 were significantly higher in patients with breast cancer than those with benign disease or normal controls. The serum concentrations of sCD44s and sCD44v6 in patients with stage Ⅲ, Ⅳ were significantly higher than those in patients with stageⅠ, Ⅱ(P＜0.01) .The level of sCD44v6 decreased markedly after one week operation and even more decreased after two weeks operation. The level of sCD44s was decreased significantly after two weeks operation. CONCLUSION: Serum levels of sCD44s and sCD44v6 may be a useful marker in the diagnosis and treatment of breast cancer. The changes in the levels of serum sCD44s and sCD44v6 may be the result of tumor burden, hence implicated in the prognosis of cancer patients.