Identification of the Interaction between P-Glycoprotein and Anxa2 in Multidrug-resistant Human Breast Cancer Cells

Objective To explore the interaction of Anxa2 with P-Glycoprotein(P-gp) in the migration and invasion of the multidrug-resistant (MDR) human breast cancer cell line MCF-7/ADR. Methods A pair of short hairpin RNA(shRNA) targeting P-gp was transfected into MCF-7/ADR cells,and monoclonal cell strains were screened.The expression of P-gp was detected by Western blot.Transwell chambers were used to observe the cell migration capacity and invasion ability.The interaction between P-gp and Anxa2 was examined by immunoprecipitation and immunofluorescence confocal microscopy analyses. Results P-gp expression was significantly knocked down,and there were notable decreasing trends in the migration and invasion capability of MDR breast cancer cells(P<0.05).There was a close interaction between Anxa2 and P-gp. Conclusions MCF-7/ADR is an MDR human breast cancer cell line with high migration and invasion abilities.The knockdown of P-gp notably impaired the migration and invasion abilities of the tumor cells.The interaction of Anxa2 with P-pg may play an important role in the enhanced invasiveness of MDR human breast cancer cells.     

Detection of copy number alteration of MTA1 in human breast cancer

OBJECTIVE The purpose of our study was to investigate the expression level of MTA1 mRNA in breast cancer and its significance in relation to clinical pathology. METHODS The expression levels of MTA1 mRNA in tumor and in paired normal adjacent tissue of 56 cases with breast cancer were detected by fluorescent quantitative polymerase chain reaction. RESULTS The expression of MTA1 mRNA was detected in 47 tumor specimens of 56 breast cancer patients （83.9%） and was significantly higher than in the paired normal breast tissue. The over expressed MTA1 mRNA was significantly associated with pathologic stage （P = 0.029）, clinical grade （P = 0.035） and lymph node status （P = 0.001）. CONCLUSION The over expression of MTA1 mRNA may play a crucial role in the development of breast cancer. As the MTA1 was comparatively highly-expressed in breast cancer, it may become a new biomarker for the diagnosis and treatment of breast cancer in the future.     

Expression of Cyclin E and Its Relationship with the Prognosis of Patients with Breast Cancer

Objective： To investigate the expression of cyclin E in breast cancer tissues and its relationship with prognosis of the patients with breast cancer. Methods： The expression of cyclin E, HER-2/neu, nm23-H1 and actin was detected in 80 breast cancer tissues and 18 benign breast tumor tissues by immunohistochemical methods. The relationship between cyclin E and the remaining genes or the clinical data of the patients with breast cancer was analyzed. Results： The over expression rate of cyclin E in malignant tissues was obviously higher than that in benign tumor tissues （P〈0.01）. The over expression of cyclin E in later stage of disease was higher than that in early stage of disease （P〈0.05）. The expression of cyclin E in ER positive tissues was lower than that in ER negative tissues （P〈0.05）. The expression of cyclin E in PR positive tissues and PR negative tissues had no significant difference （P〉0.05）. The expression of cyclin E in HER-2/neu positive tissues was higher than that in HER-2/neu negative tissues （P〈0.05）. And the expression of cyclin E in ER, PR and HER-2/neu all positive tissues was much higher （P〈0.01）. There was no significant difference in the expression of cyclin E between nm23-H1 positive tissues and nm23-H1 negative tissues （P〉0.05）. The expression of cyclin E in actin positive and continuous distribution tissues was lower than that in actin negative or discontinuous distribution tissues （P〈0.05）. Conclusion： The expression of cyclin E has a strong correlation to the prognosis of the patients with breast cancer.     

Antitumor effects of artesunate on human breast carcinoma MCF-7 cells and IGF-IR expression in nude mice xenografts

Purpose： The objective of this study was to investigate the anti-tumor effects and analyze the mechanism of artesunate （ART） action on breast cancer in vivo using tumor transplanted nude mice. Methods： The human breast tumor cell line MCF-7 was transplanted into nude mice, and the animals were treated with various doses of ART alone or in combination with cyclophosphamide （CTX） or normal saline （NS）. The tumor inhibitory effects were observed and compared, and the ultrastructural morphology of the transplanted tumor cells was observed by electron microscopy. The apoptosis rates and cell cycle status were detected by flow cytometry （FCM）. The expression of apoptosis-related proteins p53, Bcl-2, Bax and Caspase-3 were detected by immunohistochemistry and IGF-IR was detected by western blot. The expression correlation for these proteins was also analyzed. Results： The tumor inhibition rates in the low dose ART group, high dose ART group, CTX group and combined drug therapy group were （24.39±10.20）%, （40.24±7.02）%, （57.01±5.84）% and （68.29±5.1）%, respectively. The cell cycle was arrested in phase G0/Gt after treatment with ART. The expression of Bcl-2 was significantly reduced, and the expression levels of Bax and Caspase-3 were significantly increased in the ART group compared to the negative control saline group. There was no significant difference detected in p53 expression. The Bcl-2 level was negatively related to Bax and Caspase-3. The western blotting results showed IGF-IR downregulation. Conclusions： ART inhibits the growth of MCF-7 breast tumor cell xenografts in nude mice. The anti-tumor mechanism of ART for human breast carcinoma in nude mice might be correlated with the alteration of apoptosis related protein expression, which may further induce apoptosis and inhibit cell proliferation.     

DJ-1 promotes proliferation and epithelial-mesenchymal transition of colorectal cancer cells by regulating p53 signaling pathway北大核心CSCD

Objective: To investigate the effects of up-regulating or silencing DJ-1 gene expression on the apoptosis, migration and invasion of colorectal cancer (CRC), and to explore the possible molecular mechanism. Methods: The expression level of DJ-1 in CRC tissues and cells was detected by immunohistochemistry, Western blotting and real-time fluorescent quantitative PCR, respectively. The SW480 and HCT116 cells were transfected with the recombinant lentiviral vector carrying human DJ-1 gene to obtain DJ-1 overexpressed SW480/OE-DJ-1 and HCT116/OE-DJ-1 cells, while the cells transfected with the empty vector was as the negative control (OE-NC). The SW480 and HCT116 cells were transfected with the recombinant lentiviral vector carrying the specific shRNA targeting DJ-1 gene to generate the SW480/shDJ-1 and HCT116/sh-DJ-1 cells with stable knockdown of DJ-1, while the cells transfected with the empty vector was as the negative control (sh-NC). Subsequently, the expressions of DJ-1 and p53 protein and mRNA were detected by immunohistochemistry and real-time fluorescent quantitative PCR, respectively; and their relationship was analyzed. The expressions of p53 and its downstream apoptosis-related proteins Bax and Bcl-2 in SW480 and HCT116 cells with DJ-1 over-expression or knockdown were detected by Western blotting. The effects of overexpressing and silencing DJ-1 gene expression on the invasion and migration abilities of SW480 and HCT116 cells were detected by Transwell chamber assay. The epithelial-mesenchymal transition (EMT) of CRC cells was induced by transforming growth factor-β1 (TGF-β1), then the expression levels of DJ-1 and EMT-related markers (N-cadherin, β-catenin, vimentin, E-cadherin) were analyzed by Western blotting. Results: DJ-1 was highly expressed in 34 CRC tissues (24/34, 70.59%) (P < 0.001). The overall survival time of the patients with DJ-1 high expression was significantly shorter than that of the patients with DJ-1 low expression (P < 0.001). The high expression of DJ-1 was correlated with TNM stage, tumor location, lymph node metastasis, and degree of differentiation (all P < 0.05). There was a negative correlation between DJ-1 and p53 expressions (r =-0.428, P = 0.015). Silencing DJ-1 increased the expression level of p53 and its downstream apoptotic protein Bax, decreased the expression of anti-apoptotic protein Bcl-2 (all P < 0.05), and decreased the invasion and migration capacities of SW480 and HCT116 cells (both P < 0.01); Conversely, overexpressing DJ-1 decreased the expression level of p53 and Bax, increased the expression of Bcl-2 (all P < 0.05), and increased the invasion and migration capacities of SW480 and HCT116 cells (both P < 0.01). Overexpression of DJ-1 induced by TGF-β1 increased the expressions of N-cadherin, β-catenin and vimentin, and decreased the expression of E-cadherin in the process of EMT (P < 0.05). Conclusion: DJ-1 promotes the apoptosis and invasion of CRC cells by negatively regulating the p53 signaling pathway. © 2019 by TUMOR All rights reserved.     

Aberrant Expression of Notch1 in Cervical Cancer

OBJECTIVE To investigate the putative role of the Notch1 receptor in cervical cancer carcinogenesis and progression. METHODS The expression of the Notch1 protein was analyzed by a Western-blotting approach in 40 cervical cancer and 30 normal cervical tissues. Some tissues were examined using RT-PCR to determine mRNA levels. Celluar localization of the Notch1 protein in the paraffin-embedded cervical tissues was also analyzed by immunohistochemistry. RESULTS The Notch1 protein was detected in all 30 normal cervical tissues. In contrast, only 6 samples of 40 cervical cancer tissues showed Notch1 expression. The level of the Notch1 protein expression was significantly lower in cervical cancer tissues than that in normal tissue samples. In agreement with these observations, levels of Notch1 mRNA were found to be substantially down-regulated in cervical cancer tissues. In the immunohistochemistry staining assay, the Notch1 protein was shown to localize predominantly in the cytoplasm and nucleoli of the normal cervical squamous epithelium of the cervix, but no staining was observed in the cervical cancer cells. Notch1 expression was observed to correlate with the clinical disease stage, but there were no correlations with age, tumor size, grade or lymph node metastasis （P〉0.05）. The levels of Notch1 protein expression were significantly higher in early stages （Ⅰ-Ⅱa, 66.7%） compared to those in the advanced stages （Ⅱb～Ⅳ,12.6%）（P=0.001）. CONCLUSION Notch1 may play a role as a tumor suppressor in cervical tumorigenesis. Determination of Notch1 expression may be helpful for preoperative diagnosis and accuracy of staging. But its clinical use for cervical cancer requires further investigation.     

Identification of TM9SF2 as a candidate of the cell surface marker common to breast carcinoma cells

OBJECTIVE We aimed identification of cell surface molecules, which might serve as diagnostic biomarkers or useful targets for therapies, in breast cancer. METHODS We developed unique DNA microarray coupled with spherical self-organizing map （sSOM） analysis to characterize cells and tissues by the cell surface markers. In the microarray 1,797 probes for human genes coding membrane bound proteins were spotted. With this microarray the gene expression profiles of eight breast carcinoma cell lines were compared to identify the genes that were commonly expressed in breast carcinomas but not in normal cells. RESULTS The gene expression profiles of sSOM from the eight breast carcinoma cell lines were successfully distinguished from that of normal breast tissue derived cells suggesting the presence of genes of interest, sSOMon the data extensively filtered revealed several candidate genes, of which expression was significant in carcinoma cells but low in normal cells. Finally, TM9SF2 was nominated through validations of PCR procedures together with CD24 and ErbB3, which are known breast carcinoma markers. TMgSF2 expression was further confirmed by immunological staining. Interestingly, TMgSF2 was found to be expressed in all the cell lines evaluated while CD24 and ErbB3 were not in all of the carcinoma cells, supporting their relationship in sSOM. Although physiological significance of TMgSF2 is unknown yet, siRNA treatment significantly inhibited the growth of MDA- MB-231 cells. CONCLUSION We propose TM9SF2 as a novel and useful diagnostic marker as well as a potential molecular target specific to breast carcinoma cells covering wide range of breast cancer.     

High Expression of the RECK Gene in Breast Cancer Cells is Related to Low Invasive Capacity

OBJECTIVE To investigate the expression of the RECK gene in human breast (cancer) cell lines, and to determine the relationship between RECK gene expression and the invasive capacity of the breast cancer cell lines. METHODS The invasive capacity of breast (cancer) cell lines including HBL-100, MCF-7 and MDA-MB-435S were determined by the Tran-swell method. The protein expression levels of RECK, MMP-2 and MMP-9 genes in these three cell lines were measured by immunocytochemical methods. The expressions of the RECK gene and protein level were measured by RT-PCR and Western blots in the cell lines respectively. RESULTS The order of the invasive capacity of the breast (cancer) cell lines was MDA-MB-435S, being the highest, and HBL-100, being the lowest. The invasive capacity difference between any two groups among the three groups was significant (P<0.01). The protein expression level of the RECK gene in the HBL-100 cell line was highest, and no expression was detected in MDA-MB-435S cells. Moreover, the expression of the RECK gene was negatively correlated with the expression of the MMP-2 and MMP-9 genes. The mRNA level of the RECK gene in HBL-100 cells was the highest, but no expression was found in the MDA-MB-435S cells (P<0.001). CONCLUSION There was a significant negative correlation between the expression level of the RECK gene and invasive capacity in vitro, and the RECK gene expression showed an inverse proportion to that of the MMP-2, MMP-9 genes.     

Down-Regulation of Notchl and NF-κB by Curcumin in Breast Cancer Cells MDA-MB-231

Objective:To test whether the down-regulation of Notch1 gene expression by curcumin could inhibit cell growth and induce apoptosis,which may be associated mechanistically with the down-regulation of NF-κB in breast cancer cells. Methods:Breast cancer cell lines MDA-MB-231 were cultured in vitro and treated with different dosages of curcumin(0,1.25,5.0,20.0μmol/L)for dose-dependent assay and different time(0,24,48,72 h)at the dosage of 5.0μmol/L for time course assay.The changes of the mRNA and protein expression of Notch1 and NF-κB were measured by RT-PCR and Western Blot,and MTT assay was used to measure the change of proliferation. Results:The mRNA and protein levels of Notch 1 and NF-κB were decreased significantly in human breast cancer cell line with the increase of dosage of curcumin(P＜0.05),and with the extension of time course(P＜0.05).These changes suggested a dose- and time-dependent manner.The proliferation rate of cells also was significantly inhibited(P＜0.05). Conclusion:The current results show that the Notch-1 signaling pathway is associated mechanistically with NF-κB activity during curcumin-induced cell growth inhibition and apoptosis of breast cancer cells.These results suggest that the down-regulation of Notch signaling by curcumin may be a novel strategy for the treatment of patients with breast cancer.     

Expression of Preprotachykinin-I （PPT-I）, Neurokinin-1 （NK-1） and Neurokinin-2 （NK-2） in Breast Cancer Cells Improves Tumor Cell Survival in Bone Marrow in the Early Stage of Metastasis

OBJECTIVE To study the potential relationship between the expression of PPT-I, NK-1, NK2 and the development of breast cancer cells in bone marrow stroma and to provide evidence of potential molecular mechanisms of breast cancer patients. of bone metastasis in early stage METHODS The cocultures of breast cancer cell line T-47D and marrow-derived mesenchymal stem cells （MSC） were established with equal numbers. T-47D cells were separated from the coculture system at 48 h and 96 h after coculture by MACS magnetic cell sorting （MicroBeads）. The expression of PPT-I, NK-1, NK-2 in T-47D was then examined before and after coculture by real-time PCR and by Western blot. Alterations in cellular ultrastructure of T-47D cells were detected before and after coculture under electron microscope. Finally, changes in cell cycle distribution were examined by flow cytometry, and growth curves from before and after coculture were drawn and analyzed. RESULTS Following coculture of T-47D and MSC, the expression of PPT-I mRNA and protein was significantly upregulated, while the expression of NK-1 and NK-2 mRNA and protein was greatly downregulated. The analysis of cell cycle distribution by flow cytometry showed that the proportion of T-47D during S phase was increased, and the duration of the G2/M phase was sharply decreased. Under electron microscope, we observed that the synthesis of hereditary material was increased, but the hepatin granules were shown prominent stacking in T-47D cells. These results suggest that although the synthesis of DNA was increased, the proliferation of cells was inhibited after coculture. The cell growth curve confirmed the findings from the observation under the electron microscope and flow cytometry. CONCLUSION Tumor cells could survive through the upregulation in expression of preprotachykinin-I gene during early bone metastasis in breast cancer. The phenomenon of growth suppression in breast cancer cells after coculture in the current study could be induced by downregulation in expression of NK-1 and NK-2.     

黄芩素对人乳腺癌MDA-MB-231细胞株SATB1表达的影响(英文)

Baicalein had been proved to have anti-cancer activity in vitro and in vivo, including the inhibition of malignant proliferation, migration, adhesion and invasion of many kinds of cancer cells. The special AT-rich sequence binding protein 1 （SATB1） is a tissue-specific expression of nuclear matrix-binding protein and is reported to be a breast cancer ＂gene group organizer＂. Previous studies have shown that SATB1 is involved in the growth, metastasis and prognosis of breast cancer. The present study was aimed to investigate whether baicalein inhibits the proliferation and migration of MDA-MB-231 human breast cancer cells through down-regulation of the SATB1 expression. Methods： MDA-MB-231 cells were treated for 24 h, 48 h and 72 h with various concentrations of baicalein （0, 5, 10, 20, 40 and 80 pM） respectively. Then, the proliferation and migration of MDA-MB-231 cells following treatment with baicalein were determined using colorimetric 3-（4, 5-dimethylthia- zol-2-yl） 2, 5-diphenyltetrazolium bromide （MTT） and wound healing assays. Thereafter, western blot analysis was performed to detect the changes of SATB1 protein expression in MDA-MB-231 cells. Results： Along with the prolongation of time and increase of drug concentration, inhibitory effect of baicalein on proliferation and migration of MDA-MB-231 cells gradually in- creased, in a time.- and dose- dependent manner （P 〈 0.05）. Meanwhile, after treated with baicalein in different concentrations for 48 h, the level of SATB1 protein expression of MDA-MB-231 cells decreased obviously, in a dose-dependent manner （P 〈 0.05）. Conclusion： Baicalein inhibits breast cancer cell proliferation and suppresses its invasion and metastasis by reducing cell migration possibly by down-regulation of the SATB1 protein expression, indicating that baicalein is a potential therapeutic agent for human breast cancer.     

SREBP2m promotes proliferation and migration of hepatocarcinoma cells and inhibits apoptosis through cholesterol metabolism damage北大核心CSCD

Objective: To investigate the effects of sterol regulatory element binding protein 2 (SREBP2) on the metabolism of cholesterol as well as the proliferation, apoptosis and migration of normal liver LO2 cells and hepatocellular carcinoma HepG2 cells. Methods: By using pAd-Easy-1 adenovirus vector system, the recombinant adenovirus Ad-SREBP2m (carrying the splicing form of SREBP2) and Ad-GFP (as the control) were constructed, and then infected into LO2 and HepG2 cells, respectively. The total cholesterol level in LO2 and HepG2 cells after infection was detected by a cholesterol quantification kit. The expression levels of SREBP2m, cholesterol synthesis rate-limiting enzyme 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) and apoptosis-related proteins (including caspase 3, cleaved-caspase 3 and caspase 12) were detected by Western blotting. The effects of Ad-SREBP2m overexpression on the proliferation, cell cycle, apoptosis and migration of LO2 or HepG2 cells were detected by EdU staining method, FCM and scratch wound healing test, respectively. Results: The recombinant adenovirus Ad-SREBP2m was successfully constructed. Compared with the Ad-GFP group, the expression levels of SREBP2m and its target protein HMGCR were up-regulated (both P < 0.05), and the total cholesterol level increased significantly in LO2 cells and HepG2 cells infected with Ad-SREBP2m (both P < 0.05). In LO2 cells infected with Ad-SREBP2m, the proportion of G1-, S- and G2-phase cells was not significantly changed (all P > 0.05); while in HepG2 cells infected with Ad-SREBP2m, the proportion of G1-phase cells decreased significantly (P < 0.001), but the proportion of S-phase cells increased significantly (P < 0.001). SREBP2m overexpression promoted the proliferation of HepG2 cells (P < 0.001), but had no effect on the proliferation of LO2 cells. The expression levels of total caspase 3, cleaved-caspase 3 and caspase 12 were significantly higher in LO2 cells infected with Ad-SREBP2m than those in Ad-GFP group (all P < 0.001), while the expression levels of total caspase 3, cleaved-caspase 3 and caspase 12 were decreased in HepG2 cells infected with Ad-SREBP2m (all P < 0.05). The apoptosis rate of LO2 cells after Ad-SREBP2m infection was increased by (11.40±0.52)% (P < 0.001), while the apoptosis rate of HepG2 cells in Ad-SREBP2m group was decreased by (4.17±0.47)% as compared with Ad-GFP group (P < 0.05). The migration distance of HepG2 cells in Ad-SREBP2m group was (1.17±0.12) mm more than that in Ad-GFP group (P < 0.05). Conclusion: Overexpression of SREBP2m can promote the proliferation and migration and inhibit the apoptosis of hepatocellular carcinoma HepG2 cells, but it can promote apoptosis of normal liver LO2 cells. Copyright © 2018 by TUMOR. All rights reserved.     

EXPRESSION OF E-CADHERIN/CATENIN COMPLEX IN BREAST CANCER

Objective： To detect the expressions of E-cadherin, α-catenin and β-catenin and analyze the relationship between Ecadherin-catenin adhesion complex and clinicopathological features in breast cancer. Methods： The expressions of E-cadherin, α-cadherin and β-catenin in specimens of 54 breast cancer, 21 normal breast tissues around tumor, 15 breast hyperplasia of usual type and 15 breast atypical hyperplasia were detected by immunohistochemical method. Results： In 21 normal breast tissues, E-cadherin and α-catenin were expressed on cell membrane of ductal and acinic cells, showing cellular contour and border among cells. The staining character of the three proteins in breast hyperplasia of usual type was the same as that in normal breast tissue. In breast atypical hyperplasia, the abnormal expression rates of E-cadherin, α-catenin and β-catenin were 6.7%, 13.3% and 26.7%, respectively. The total abnormal expression rate of E-cadherin-catenin complex was 33.3%. In breast cancer, the abnormal expression rates of E-cadherin, α＋catenin and β-catenin were 51.9%, 63.0% and 61.1%, respectively. The total abnormal expression rate of E-cadherin-catenin complex was 88.9%. Abnormal expression of E-cadherin and α-catenin were significantly correlated with histological grade. Abnormal expressions of α-catenin and β-catenin were significantly correlated with TNM staging, axillary lymph nodes metastasis and postoperative distant metastasis. Abnormal expression of E-cadherin-catenin complex was correlated with TNM staging, histological grade and axillary lymph nodes. Abnormal expression of β-catenin was negatively correlated with expression of HER-2. COX multiple factor analysis showed that E-cadherin or α-catenin or β-catenin was not independent prognostic indicator. Conclusion： Abnormal expressions of E-cadherin, α-catenin and β-catenin frequently occur in breast cancer. Abnormal expression of E-cadherin-catenin complex is correlated with differentiation disturbance and metastasis. Combined measurement of E-caherin, α-catenin and β-catenin may improve accuracy and sensitivity of predicting metastasis and prognosis of breast cancer.     

MAT1-siRNA体外转染抑制胰腺癌的细胞增殖和侵袭能力的研究

ObjectiveTo observe the feasibility of gene silencing of MAT1 gene by small interference RNA in human pancreatic cancer cells.MethodsBxPC-3 cells were transfected using chemically synthesized double stranded RNA formulated with liposome.Gene expression of MAT1 was assayed by RT-PCR and Western blot respectively.The cell proliferation assay was carded out by counting alive cells after Trypan blue exclusion.The cells invasion ability was determined by Boyden chamber model.ResultsThe MAT1 mRNA and protein expression of BxPC-3 cells were significantly down-regulated by small interference RNA compared with the control groups.The expression of MAT1 mRNA was reduced by 55.2% and 64.3% in 24 h and 48 h respectively (P＜0.01).The cell proliferation and invasion ability of BxPC-3 cell were significantly inhibited (P＜0.01).ConclusionThe results suggest that gene silencing of MAT1 by siRNA can inhibit the cell proliferation and invasion of BxPC-3 cells,which may be a target in the gene therapy of human pancreatic cancer.     

Autophagy Enhances the Aggressiveness of Human Colorectal Cancer Cells and Their Ability to Adapt to Apoptotic Stimulus

Objective To investigate LC3B-Ⅱand active caspase-3 expression in human colorectal cancer to elucidate the role of autophagy and to explore the relationship of autophagy with apoptosis in human colorectal cancer. Methods LC3B expression was detected by immunohistochemistry in 53 human colorectal cancer tissues and 20 normal colon tissues.The protein levels of LC3B-Ⅱand active caspase-3 were also determined by Western blot analysis in 23 human colorectal cancer tissues and 10 normal colon tissues. Results LC3B was expressed both in cancer cells and normal epithelial cells.LC3B expression in the peripheral area of cancer tissues was correlated with several clinicopathological factors,including tumor differentiation(P=0.002),growth pattern of the tumor margin (P=0.028),pN(P=0.002),pStage(P=0.032),as well as vessel and nerve plexus invasion(P=0.002).The protein level of LC3B-Ⅱin cancer tissue was significantly higher than in normal tissue(P=0.038),but the expression of active forms of procaspase-3 in cancer tissue was lower(P=0.041).There was a statistically significant positive correlation between the expression levels of LC3B-Ⅱand the active forms of procaspase-3(r=0.537,P=0.008). Conclusions Autophagy has a prosurvival role in human colorectal cancer.Autophagy enhances the aggressiveness of colorectal cancer cells and their ability to adapt to apoptotic stimulus.     

Study on inhibition of growth of ACHN cells via shRNA expression vector-mediated cyclinE1 gene silencing

OBJECTIVE To explore the inhibition of ACHN cells via shRNA expression vector mediated cyclinE1 gene silencing. METHODS The shRNA targeting at cyclinE1 gene was designed and synthesized. By ligation, the fragment was inserted into pGenesil-1-U6 to construct the recombinant plasmid pGenesil-1- U6-cyclinE1. The identified recombinant plasmid was introduced into ACHN cells with lipofectamine 2000. The inhibition of cyclinE1 mRNA and protein expression were analyzed by RT-PCR and western-blotting. MTT method was used for observing cell proliferation and drawing growth curve. The cell cycle and ratios of apoptotic cell were assessed by flow cytometric detection. The ability of invasion and speed of cell migration were detected by transwell chamber invasive models and cell scratch method. RESULTS The inhibition of expression of cyclinE1 in ACHN cells mediated by recombinant vector （0.0933 ± 0.05） was significantly lower than that in the group of transfected with empty vector （0.8827 ± 0.04） and the control group （0.9021±0.03） （P 〈 0.05）. Flow cytometry showed that recombinant cells were blocked in the G1 phase and the apoptotic ratio was increased significantly （11.15 ± 4.00）% （P 〈 0.05）. The curves of cell growth indicated that the proliferation of cell transfected with recombinant plasmid was inhibited significantly compared with that in control group （P 〈 0.05）. The results of transwell and cell scratch suggested that the abilities of invasion and migration of the cells transfected with recombinant plasmid were decreased conspicuously （P 〈 0.05）. CONCLUSION The expression of cyclinE1 could be inhibited successfully by RNA interference induced by shRNA expression vector. This consequently inhibits the cell growth and induces apoptosis. Our study provided a preliminary result in searching of RNA interference （RNAi） therapy for renal cell carcinoma.     

Tripartite motif-containing 3 (TRIM3) inhibits tumor growth and metastasis of liver cancer

Background:Reduced expression of tripartite motif-containing 3 (TRIM3) has been reported to be involved in the pathogenesis of human glioblastoma.In our previous research,we found that TRIM3 expression was markedly reduced in human primary hepatocellular carcinoma (HCC) tissues and that low TRIM3 expression was associated with short survival of HCC patients.However,the role of TRIM3 in liver cancer remains unknown.This study aimed to investigate the function of TRIM3 in liver cancer cells.Methods:The protein levels of TRIM3 in five liver cancer cell lines (SK-Hep1,Hep3B,Huh7,HepG2,Bel-7402) and one normal liver cell line (L02) were detected with Western blotting.HepG2 and Bel-7402 cells with IowTRIM3 expression were infected with recombinant lentiviruses overexpressing TRIM3 (LV-TRIM3),whereas Huh7 and Hep3B cells with high TRIM3 expression were transfected with TRIM3-targeted small interfering RNA (siTRIM3).The functions of TRIM3 in the proliferation,colony formation,cell cycle,migration,invasion,and apoptosis of the above cell lines were examined.The effect of TRIM3 on tumor growth and metastases in nude mice was also investigated.Results:TRIM3 was overexpressed in HepG2 and Bel-7402 cells with LV-TRIM3 infection,which further reduced proliferation,colony formation,migration,and invasion of both cell lines.Cell cycle analysis showed thatTRIM3 overexpression induced G0/G1 phase arrest in HepG2 and Bel-7402 cells.Moreover,apoptosis was not increased in HepG2 or Bel-7402 cells overexpressing TRIM3.Contrarily,silencing TRIM3 expression in Huh7 and Hep3B cells by siTRIM3 led to significantly decreased percentages of both cells in the G0/G1 phase and promoted cell proliferation,colony formation,migration,and invasion.In vivo experiment results confirmed thatTRIM3 overexpression suppressed tumor growth and metastasis.Conclusions:TRIM3 plays a tumor-suppressing role in the regulation of liver cancer development by reducing cell proliferation through cell cycle arrest at the G0/G1 phase.