Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 10 de 10
Filter
1.
Chinese Journal of Oncology ; (12): 264-268, 2012.
Article in Chinese | WPRIM | ID: wpr-335299

ABSTRACT

<p><b>OBJECTIVE</b>Isolate and characterize the side population (SP) cells with potency of stem cells from human gastric carcinoma cell line BGC-823.</p><p><b>METHODS</b>SP and non-SP cells were sorted from BGC-823 cells by fluorescence-activated cell sorting (FACS) using Hoechst33342 staining. The tumorigenic ability of the SP cells was assessed by in vivo transplantation into non-obese diabetic/severe combined immunodeficiency mice.</p><p><b>RESULTS</b>SP cells were isolated from BGC-823 cells in a proportion of 0.9% to 2.1% with respect to the whole cell population. The colony formation assay showed that the colony formation rate of the SP cells was significantly higher than that of the non-SP cells (72.56% vs. 49.00%, P < 0.01). The drug sensitivity test showed that the SP cells showed stronger drug resistance to 5-Fu than the non-SP cells. The in vivo transplantation of SP cells in mice showed that the tumor weight was (0.176 ± 0.034) g, significantly higher than that of non-SP cells (0.045 ± 0.046) g (P < 0.01).</p><p><b>CONCLUSIONS</b>The results of this study indicate the existence of cancer stem-like SP cells in the human gastric cancer line BGC-823 cells. Further characterization of this SP cell population may provide new insights for diagnosis and treatment of gastric cancer.</p>


Subject(s)
Animals , Female , Humans , Mice , Antimetabolites, Antineoplastic , Pharmacology , Cell Line, Tumor , Cell Proliferation , Colony-Forming Units Assay , Drug Resistance, Neoplasm , Fluorouracil , Pharmacology , Mice, Inbred NOD , Mice, SCID , Side-Population Cells , Pathology , Transplantation , Stomach Neoplasms , Pathology
2.
Chinese Medical Journal ; (24): 2708-2714, 2011.
Article in English | WPRIM | ID: wpr-292818

ABSTRACT

<p><b>BACKGROUND</b>The potential application of retinoic acid receptor activators, such as all trans-retinoic acid (ATRA), for treating various cancers have been studied both pre-clinically and clinically. Whether ATRA has an anticancer effect on human esophageal squamous cancer cell (ESCC) is still unknown. We have explored the anticancer effect of ATRA in ESCC, and in this study, the effects of ATRA on levels and patterns of expression of the vascular endothelial growth factor (VEGF) signal transduction pathway in transplantable tumor growth of the human ESCC cell line, EC9706, in nude mice.</p><p><b>METHODS</b>The animal model of the ESCC xenograft was made by subcutaneous implantation of tumor cells into nude mice. Reverse transcription-polymerase chain reaction (RT-PCR), Western blotting and immunohistochemical assays were used to detect the expression of the VEGF signal transduction pathway in ESCC xenograft tissues.</p><p><b>RESULTS</b>Compared to the control group, the tumor inhibition rates in the low dose ATRA, high dose ATRA, and 5-FU groups were 83.21%, 88.32%, 91.02%, respectively. The protein and mRNA levels of VEGF were down-regulated after being treated with ATRA and 5-FU compared to the control group (P < 0.05). The study also revealed that ATRA specifically down-regulated VEGF and the component of the VEGF signal transduction pathway of CD31, CD34, and CD105 (component of the TGF-β receptor) in ESCC xenograft tissues (P < 0.05).</p><p><b>CONCLUSIONS</b>ATRA can significantly inhibit tumor growth and has anticancer effects on transplantable tumor growth of human ESCC cell line EC9706 in nude mice. These findings indicate that ATRA specifically down regulated VEGF and the components of VEGF signal transduction, which may be an important mechanism responsible for the neoangiogenesis inhibition of ESCC cells.</p>


Subject(s)
Animals , Humans , Mice , Blotting, Western , Carcinoma, Squamous Cell , Drug Therapy , Metabolism , Cell Line, Tumor , Esophageal Neoplasms , Drug Therapy , Metabolism , Immunohistochemistry , Mice, Nude , Neovascularization, Pathologic , Drug Therapy , Metabolism , Real-Time Polymerase Chain Reaction , Tretinoin , Therapeutic Uses , Vascular Endothelial Growth Factor A , Metabolism , Xenograft Model Antitumor Assays
3.
Acta Academiae Medicinae Sinicae ; (6): 456-461, 2011.
Article in Chinese | WPRIM | ID: wpr-341385

ABSTRACT

Differentiated somatic cells can be directly reprogrammed into induced pluripotent stem (iPS) cells in vitro. Similarly to embryonic stem (ES) cells, iPS cells have pluripotency to differentiate into all cell types and capability to self-renew themselves indefinitely. Without immune rejection and ethical issues, patient-specific iPS cells promise to be an ideal tool for regenerative medicine, drug screening, and toxicity testing.


Subject(s)
Humans , Induced Pluripotent Stem Cells
4.
Chinese Journal of Oncology ; (12): 570-573, 2011.
Article in Chinese | WPRIM | ID: wpr-320168

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the mechanism of loss of human esophageal cancer-related gene 4 (ECRG4) expression in esophageal squamous cell carcinoma (ESCC.)</p><p><b>METHODS</b>PCR-SSCP and DNA sequencing analysis were used to detect the mutation of ECRG4 exons in esophageal cancer and matched adjacent normal tissues of 80 patients. DNA bisulfite-modifying ssPCR sequencing assay was used to examine the methylation status of ECRG4 promoter in human esophageal squamous cell carcinoma EC9706 cells. The re-expression of ECRG4 mRNA was examined by RT-PCR in EC9706 cells, after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide.</p><p><b>RESULTS</b>No mutation in the four ECRG4 exons was found in all the ESCC and matched normal adjacent tissues. RT-PCR showed that 11 of 16 CpG islands of ECRG4 promoter were hypermethylated, while ECRG4 mRNA expression level was undetectable in the EC9706 cells. The ECRG4 mRNA was re-expressed after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide.</p><p><b>CONCLUSION</b>The epigenetic mechanism of methylation is a reason of loss of ECRG4 gene expression in the ESCC cell line EC9706.</p>


Subject(s)
Humans , Antimetabolites, Antineoplastic , Pharmacology , Antineoplastic Agents , Pharmacology , Arsenicals , Pharmacology , Azacitidine , Pharmacology , Carcinoma, Squamous Cell , Genetics , Metabolism , Pathology , Cell Line, Tumor , CpG Islands , Genetics , DNA Methylation , Epigenesis, Genetic , Esophageal Neoplasms , Genetics , Metabolism , Pathology , Exons , Gene Expression Regulation, Neoplastic , Mutation , Neoplasm Proteins , Genetics , Metabolism , Oxides , Pharmacology , Promoter Regions, Genetic , RNA, Messenger , Metabolism
5.
Chinese Journal of Oncology ; (12): 609-612, 2011.
Article in Chinese | WPRIM | ID: wpr-320160

ABSTRACT

<p><b>OBJECTIVE</b>To explore the correlation of IGF-1R expression with clinical features of esophageal squamous cell carcinoma (ESCC) and to investigate the effect of silencing IGF-1R by siRNA on the proliferation of esophageal cancer cell line EC9706 cells.</p><p><b>METHODS</b>Immunohistochemistry was used to detect the expresion of IGF-1R in 80 specimens of ESCC and 18 specimens of normal esophageal mucosa. IGF-1R siRNA was transfected into esophageal squamous cell carcinoma EC9706 cells, and the effect of RNAi was assessed by Western blot. The proliferation of EC9706 cells was determined by drawing growth curve, MTT assay and plate colony-forming assay.</p><p><b>RESULTS</b>The total and strong positive rates of IGF-1R expression were 86.3% and 51.3% in ESCC, and 61.1% and 11.1% in normal esophageal epithelium, respectively. The total and strong positive rates of IGF-1R expression in patients with lymph node metastasis were 94.4% and 74.1%, significantly higher than 69.2% and 3.9%, respectively, in those without lymph node metastasis (P<0.01). A significantly higher IGF-1R expression was associated with lower histological grade (P<0.05). The total and strong rates of IGF-1R expression in 39 patients of stages III and IV were 97.4% and 71.8% , significantly higher than the 75.6% and 31.7%, respectively, in 41 cases of stages I and II (P<0.01). IGF-1R RNAi significantly inhibited IGF-1R expression and the growth of EC9706 cells. The clone formation rate of RNAi-IGF-1R transfected cells was 19.1%, significantly lower than that of 52.3% in non-transfected cells and 49.0% in empty vector-transfected EC9706 cells (P<0.05).</p><p><b>CONCLUSIONS</b>The overexpression of IGF-1R is colerated with lymph node metastasis, differentiation and clinical stage. Down-regulation of IGF-1R can inhibit the proliferation of esophageal cancer EC9706 cells in vitro.</p>


Subject(s)
Aged , Female , Humans , Male , Middle Aged , Carcinoma, Squamous Cell , Genetics , Metabolism , Pathology , Cell Line, Tumor , Cell Proliferation , Down-Regulation , Esophageal Neoplasms , Genetics , Metabolism , Pathology , Gene Expression Regulation, Neoplastic , Lymphatic Metastasis , Neoplasm Grading , Neoplasm Staging , RNA Interference , RNA, Small Interfering , Genetics , Receptor, IGF Type 1 , Genetics , Metabolism , Transfection
6.
Chinese Journal of Oncology ; (12): 169-172, 2010.
Article in Chinese | WPRIM | ID: wpr-260443

ABSTRACT

<p><b>OBJECTIVE</b>To explore the possibility of use of insulin as a potentiator of 5-Fu to human colon cancer cell lines HCT-8 and HT-29 and study its mechanism.</p><p><b>METHODS</b>MTT assay was used to examine the inhibition rate of cell growth after treatment with 5-Fu and insulin. Cell cycle was determined by flow cytometry.</p><p><b>RESULTS</b>Insulin showed an enhancing effect on the chemotherapeutic response of 5-Fu when insulin was applied at a dose of exceeding 0.8 mU/ml 0 approximately 8 h before 5-Fu. Within the range of from 0.8 mU/ml to 8 mU/ml, a higher concentration of insulin gave a higher proportion of inhibited cells. But when the insulin concentration exceeds 8 mU/ml, the proportion became stable as that of 8 mU/ml. Insulin increased the percentage of S phase cells and decreased the percentage of G(1) phase cells (P < 0.01). The percentage of S phase cells reached a peak when the cells were treated with insulin for 6 hours.</p><p><b>CONCLUSION</b>Insulin can enhance the anticancer toxicity of 5-Fu to human colon cancer cell lines HCT-8 and HT-29 cells. Insulin increases the percentage of S phase cells, which may be one of the main mechanisms of insulin-induced enhancement of anticancer response of cancer cells to 5-Fu chemotherapy.</p>


Subject(s)
Humans , Antimetabolites, Antineoplastic , Pharmacology , Cell Cycle , Cell Line, Tumor , Cell Proliferation , Colonic Neoplasms , Pathology , Dose-Response Relationship, Drug , Fluorouracil , Pharmacology , HT29 Cells , Insulin , Pharmacology , S Phase , Time Factors
7.
Chinese Journal of Oncology ; (12): 663-666, 2010.
Article in Chinese | WPRIM | ID: wpr-293531

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the impact of all-trans retinoic acid (ATRA) on chemosensitivity to esophageal squamous cell carcinoma EC9706 cells in vitro and its mechanism.</p><p><b>METHODS</b>EC9706 cells were routinely cultured as the control group. The experimental group was divided into three groups. The ATRA group with ATRA in final concentration of 1 µmol/L; the 5-Fu group with 5-Fu in final concentration of 50 mg/L; the combined treatment group with ATRA in final concentration of 1 µmol/L and 5-Fu 50 mg/L. The cell apoptosis was detected by terminal deoxynucleotidy transferase mediated dUTP nick end labelling (TUNEL). The cell cycle and apoptosis were detected by flow cytometry.</p><p><b>RESULTS</b>The results of TUNEL showed that in the combined treatment group appeared a large number of apoptotic cells, and their nuclei were stained brown, with a positive rate of 89.7%. There was a significant difference in the comparison with the ATRA group (38.3%) and 5-Fu group (40.3%) (P < 0.05). The flow cytometry showed that the ATRA + 5-Fu group had a significantly higher apoptosis rate (76.9% ± 2.7%) than that in the ATRA group (38.2% ± 2.6%) and 5-Fu group (45.2% ± 2.3%) (P < 0.05). The ratio of cells in G(1) phase increased in the ATRA + 5-Fu group (83.4% ± 3.0%), significantly higher than (48.2% ± 2.5%) in the ATRA group and (53.2% ± 2.6%) in the 5-Fu group (P < 0.05). The ratio of cells in S + G(2)/M phase was decreased in the ATRA + 5-Fu group, with a significant difference (P < 0.05) when compared with other groups. There was no significant difference between the ATRA group and 5-Fu group (P > 0.05) in the apoptosis rate and the proportion of cells at different phases.</p><p><b>CONCLUSION</b>ATRA can induce apoptosis of esophageal carcinoma EC9706 cells in vitro. The combination of ATRA and 5-Fu may enhance the chemotherapeutic efficacy.</p>


Subject(s)
Humans , Antimetabolites, Antineoplastic , Pharmacology , Antineoplastic Agents , Pharmacology , Apoptosis , Carcinoma, Squamous Cell , Pathology , Cell Cycle , Cell Line, Tumor , Drug Synergism , Esophageal Neoplasms , Pathology , Fluorouracil , Pharmacology , Tretinoin , Pharmacology
8.
Chinese Journal of Oncology ; (12): 892-896, 2010.
Article in Chinese | WPRIM | ID: wpr-293458

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the mechanism of apoptosis of EC9706 tumor-bearing nude mice induced by all-trans retinoic acid (ATRA).</p><p><b>METHODS</b>Human esophageal carcinoma cell line EC9706 cells were inoculated into nude mice to establish the solid tumor model. The tumor models were divided into the following groups: ATRA group, fluorouracil group, the two-drugs combination group, and with an equal volume fraction of solvent as the control group. The nude mice were sacrificed after 10 days of medication. TUNEL staining was used to detect cell apoptosis. RT-PCR was used to detect the expression level of mRNA and immunohistochemistry was used to detect the expression level of protein of caspase-3 and survivin, the apoptosis-related genes in the tumor tissue.</p><p><b>RESULTS</b>The apoptosis rates of the ATRA group, 5-Fu group and ATRA + 5-Fu group were 44.3%, 39.7% and 91.0%, respectively. There was a significant difference in comparison with the control group (0.7%), and the ATRA group had no significant difference compared with that of the fluorouracil group (P > 0.05), but the apoptosis rate of the two-drugs combination group was significantly higher than that in the two single-drug groups (P < 0.05). The average gray value of caspase-3 protein expressed in the control group was 46.12 ± 0.33 and the relative expression of caspase-3 mRNA was 0.14 ± 0.03, both were significantly lower than that in the ATRA group, 5-Fu group and the two-drugs combination group (P < 0.05). The average gray value of survivin protein expressed in the control group was 96.07 ± 0.13 and the relative expression of survivin mRNA was 0.84 ± 0.04, both were significantly higher than those of other groups (P < 0.05). The ATRA group had no significant difference compared with the fluorouracil group (P > 0.05), but the two-drugs combination group was significantly different compared with the single-drug groups (P < 0.05).</p><p><b>CONCLUSION</b>Apoptosis in the EC9706 tumor cells in nude mice can be induced by ATRA. The mechanism may be related with down-regulation of the level of survivin gene expression and up-regulation of the level of caspase-3 gene expression.</p>


Subject(s)
Animals , Female , Humans , Male , Mice , Antimetabolites, Antineoplastic , Pharmacology , Antineoplastic Agents , Pharmacology , Apoptosis , Caspase 3 , Genetics , Metabolism , Cell Line, Tumor , Esophageal Neoplasms , Metabolism , Pathology , Fluorouracil , Pharmacology , Inhibitor of Apoptosis Proteins , Genetics , Metabolism , Mice, Nude , Neoplasm Transplantation , RNA, Messenger , Metabolism , Tretinoin , Pharmacology
9.
Chinese Journal of Oncology ; (12): 685-688, 2007.
Article in Chinese | WPRIM | ID: wpr-298518

ABSTRACT

<p><b>OBJECTIVE</b>To evaluate the expression of ezrin and CD44-v6 in esophageal squamous cell carcinoma, and to evaluate its relationship with lymph node metastasis (LNM) and histological grading.</p><p><b>METHODS</b>The expression of ezrin and CD44-v6 in 71 patients with esophageal squamous cell carcinoma was studied using immunohistochemical (SP) method. The correlation of their expression with relevant clinical data was statistically analyzed.</p><p><b>RESULTS</b>In normal esophageal squamous epithelia, the expression of ezrin was found in 33 cases among 71 cases and the expression of CD44-v6 in 18 cases among 71 cases. In esophageal squamous cell carcinoma, the expression of ezrin was found in 64 cases among 71 cases and CD44-v6 in 58 cases among 71 cases. The expression of ezrin was closely related to LNM. The positive rate of ezrin expression in LNM cases was significantly higher than that in cases without LNM. The expression of CD44-v6 had a close relation to tumor differentiation and LNM. The positive rate of CD44-v6 expression in LNM cases was significantly higher than that in patients without LNM. The expression of ezrin in CD44-v6 positive cases was significantly higher than that of CD44-v6 negative cases. The LNM rate was 60.0% in 48 patients with positive expression of both ezrin and CD44-v6, while none of lymph node metastasis was found in the 6 patients with both negative.</p><p><b>CONCLUSION</b>The test of CD44-v6 and ezrin expression may have significant prognostic value for assessing the degree of malignancy and potential LNM probability of ESCC. Ezrin may become a new target in evaluation of tumor prognosis.</p>


Subject(s)
Female , Humans , Male , Middle Aged , Carcinoma, Squamous Cell , Metabolism , Pathology , Cytoskeletal Proteins , Metabolism , Esophageal Neoplasms , Metabolism , Pathology , Hyaluronan Receptors , Metabolism , Immunohistochemistry , Lymphatic Metastasis , Neoplasm Staging
10.
Chinese Journal of Oncology ; (12): 822-825, 2007.
Article in Chinese | WPRIM | ID: wpr-298503

ABSTRACT

<p><b>OBJECTIVE</b>To study the anti-tumor effects of all-trans retinoic acid (ATRA) and mechanisms of its action.</p><p><b>METHODS</b>Human esophageal carcinoma cell line EC9706 cells were treated with ATRA at different concentration. The proliferation inhibition was examined by MTT assay. Morphological examination, TUNEL method and flow cytometry were used to detect the apoptosis and changes of cell cycle. Immunohistochemical method was used to detect the expression of apoptosis-related genes caspase-3 and bcl-2. The semi-quantification of protein expression was analyzed by pathological image analysis.</p><p><b>RESULTS</b>ATRA inhibited the proliferation of EC9706 cells moderately. Apoptosis in EC9706 cells was induced by ATRA treatment. The morphology of EC9706 cells showed changes such as nuclear chromatin condensation and fragmentation. Sub-G1 peak was found by flow cytometry. The maximal apoptosis rate was 32.6%. The expression of caspase-3 gene was enhanced. The expression of bcl-2 gene was decreased. All these effects were presented in a dose-dependent and time-depend manner.</p><p><b>CONCLUSION</b>Apoptosis is one of the key mechanisms of ATRA action on EC9706 cells.</p>


Subject(s)
Humans , Antineoplastic Agents , Pharmacology , Apoptosis , Caspase 3 , Metabolism , Cell Cycle , Cell Line, Tumor , Cell Proliferation , Dose-Response Relationship, Drug , Esophageal Neoplasms , Metabolism , Pathology , Proto-Oncogene Proteins c-bcl-2 , Metabolism , Tretinoin , Pharmacology
SELECTION OF CITATIONS
SEARCH DETAIL