OBJECTIVE Because almost all malignancies represent monoclonal proliferations, we have studied the clonal status of peripheral papillomas （peri-PM）, ductal carcinomas in situ （DCIS）, and normal breast tissues to e...OBJECTIVE Because almost all malignancies represent monoclonal proliferations, we have studied the clonal status of peripheral papillomas （peri-PM）, ductal carcinomas in situ （DCIS）, and normal breast tissues to explore a reliable way to distinguish benign and malignant （or pre-malignant） cases previously diagnosed morphologically. METHODS Twenty-six cases of peri-PM, 25 cases of peri-PM with atypical ductal hyperplasia （ADH）, 27 cases of DCIS, 16 cases of developed canceration and 20 specimens of normal tissue were examined in the study. The clonal status of these tissues was studied using an assay based on inactivation mosaicism of the lenth-polymorphic X-chromosomes at the androgen receptor （AR） locus. RESULTS Loss of polymorphism at the AR locus was found in all DCIS cases and 10 cases （10/25, 40.0%） of peri-PM with ADH, in.dicating the monoclonality of the tumors. Twenty-four out of 26 （92.3%） cases with peri- PM and 19 specimens of normal tissue were shown to be polyclonal. In 16 cases of developed Canceration, identical X chromosome inactivation （monoclonal alterations） was observed from both the peri-PM with ADH part, and the DCIS part in each Case. CONCLUSION These results contribute to the understanding of the genetic changes of peri-PM, and confirm the peri-PM with ADH as a precancerous lesion of the breast. Clonal analysis might be a useful modality to screen high-risk cases from precancerous lesions or to distinguish between benign hyperplasia and early carcinoma.展开更多
OBJECTIVE The aim of this research was to clone and express the antigen of the previously prepared monoclonal antibody named M4G3. METHODS Western blots were used to screen a breast cancer cell line that overexpresses...OBJECTIVE The aim of this research was to clone and express the antigen of the previously prepared monoclonal antibody named M4G3. METHODS Western blots were used to screen a breast cancer cell line that overexpresses the M4G3-associated antigen. A λ, zap cDNA expression library of breast cancer cells was constructed and screened using M4G3 as a probe to clone the antigen. The positive clones were subcloned and identified by homologous comparison using BLAST. RESULTS The λ zap cDNA expression library had 1.0×10^6 independent clones. Fifteen positive clones were isolated following 3 rounds of immunoscreening and identified as being from Mycoplasma pulmonis. CONCLUSION The specific antigen that matched the monoclonal M4G3 antibody is an unknown protein of M. pulmonis. This work is helpful for the further study of the association of M. pulmonis infection with breast cancer.展开更多
OBJECTIVE To investigate the efficiency of gene silencing by CXCR4- siRNAs （small interfering RNA）, and to examine the invasive ability and the expression of other metastatic-associated genes in siRNA-treated breast...OBJECTIVE To investigate the efficiency of gene silencing by CXCR4- siRNAs （small interfering RNA）, and to examine the invasive ability and the expression of other metastatic-associated genes in siRNA-treated breast cancer cells.METHODS Three siRNAs were designed and cloned into the pSilenc ^TM 3.1-H1 neo vector. The reconstructed plasmids were purified and transfected into the T47D breast cancer cell line, which highly expressed CXCR4. The amount of CXCR4 expression in the transfected cells was measured by flow cytometry and Real-time PCR. Cell invasive ability was evaluated using 24-well Matrigel invasion chambers. In addition, the expression of other metastatic-associated genes, such as E-cad, IGFBP-5, FN and MMP-2, was assessed by Real-time PCRRESULTS The suppression rates of CXCR4 mRNA expression reached 95.7%, 85.9% and 98.3%compared with control-siRNA cells in the 3 CXCR4- siRNA T47D cells respectively. FCM assays for CXCR4 protein expression showed a similar inhibitory effect. The invasion indexes of these CXCR4- siRNA cells were 0.037, 0.290 and 0.188 respectively compared with control- siRNA cells. After treatment of the cells with CXCR4-siRNA, the expression of E-cad showed an upward tendency and that of IGFBP-5 had a downward trend, while alteration in expression of FN and MMP2 varied without a consistant effect.CONCLUSION CXCR4 plays an important role in modulating migra- tion of human breast cancer cells. Small interfering RNA can significantly silence the CXCR4 gene in the human T47D breast cancer cell line. The results of this study strengthen the need for further research on novel gene therapy against breast cancer metastasis.展开更多
OBJECTIVE Hepatocellular carcinoma （HCC） is a hypervascular tumor for which angiogenesis plays an important role in its progression, The aim of this study was to investigate the expression of TWIST and VEGF and dete...OBJECTIVE Hepatocellular carcinoma （HCC） is a hypervascular tumor for which angiogenesis plays an important role in its progression, The aim of this study was to investigate the expression of TWIST and VEGF and determine their roles in angiogenesis of HCC, METHODS Expression Twist and VEGF mRNA was determined by realtime RT-PCR in 30 pairs of hepatocellular carcinoma and matched noncancerous tissues. Immunohistochemistry was carried out to analyze the protein expression of Twist and VEGF in 40 hepatocellular carcinoma cases. Staining of endothelial cells for CD34 was used to evaluate the microvessel density （MVD）. RESULTS We found that the HCC specimens showing positive Twist expression in tumor cells had a higher microvessel density than those without Twist expression. Furthermore, we found that overexpression of the Twist protein positively correlated with up-regulation of VEGF in the HCC tissues （r=0.479, P=0,002）. CONCLUSION Qur results demonstrate that Twist may play an important role in the angiogenesis of HCC and a high-level of Twist expression may be related to the malignant potential of tumor cells,展开更多
OBJECTIVE To investigate the effect of proteasome inhibition on the sensitivity of carcinoma cells to TRAIL-inducing apoptosis, and to study the mechanism of the response. METHODS Human hepatocellular carcinoma cells,...OBJECTIVE To investigate the effect of proteasome inhibition on the sensitivity of carcinoma cells to TRAIL-inducing apoptosis, and to study the mechanism of the response. METHODS Human hepatocellular carcinoma cells, pretreated with the proteasome inhibitor, MG132, were cotreated with TRAIL. Western blot assays, immunoprecipitation and RT-PCR were performed to test the expression of the Bcl-2 family proteins and Bax mRNA. RESULTS We found that (i) proteasome inhibition sensitized the human hepatocellular carcinoma cells to TRAIL; and (ii) resulted in Bax accumulation before release of cytochrome C and induction of apoptosis. These results were associated with the ability of proteasome inhibitors to overcome Bcl-2-mediated antiapoptotic function; (iii) Bax is regulated by an ubiquitin/proteasome-dependent degradation pathway. CONCLUSION Proteasome inhibition sensitized hepatocellular carcinoma cells to TRAIL by the inhibition of the ubiquitin/proteasome-mediated Bax degradation pathway.展开更多
Coronal mass ejections(CMEs)are one of the major disturbance sources of space weather.Therefore,it is of great significance to determine whether CMEs will reach the earth.Utilizing the method of logistic regression,we...Coronal mass ejections(CMEs)are one of the major disturbance sources of space weather.Therefore,it is of great significance to determine whether CMEs will reach the earth.Utilizing the method of logistic regression,we first calculate and analyze the correlation coefficients of the characteristic parameters of CMEs.These parameters include central position angle,angular width,and linear velocity,which are derived from the Large Angle and Spectrometric Coronagraph(LASCO)images.We have developed a logistic regression model to predict whether a CME will reach the earth,and the model yields an F1 score of 30%and a recall of 53%.Besides,for each CME,we use the recommendation algorithm to single out the most similar historical event,which can be a reference to forecast CMEs geoeffectiveness forecasting and for comparative analysis.展开更多
基金This work was supported by a grant from theTianjin Scientific Foundation Committee(No.033611911).
文摘OBJECTIVE Because almost all malignancies represent monoclonal proliferations, we have studied the clonal status of peripheral papillomas （peri-PM）, ductal carcinomas in situ （DCIS）, and normal breast tissues to explore a reliable way to distinguish benign and malignant （or pre-malignant） cases previously diagnosed morphologically. METHODS Twenty-six cases of peri-PM, 25 cases of peri-PM with atypical ductal hyperplasia （ADH）, 27 cases of DCIS, 16 cases of developed canceration and 20 specimens of normal tissue were examined in the study. The clonal status of these tissues was studied using an assay based on inactivation mosaicism of the lenth-polymorphic X-chromosomes at the androgen receptor （AR） locus. RESULTS Loss of polymorphism at the AR locus was found in all DCIS cases and 10 cases （10/25, 40.0%） of peri-PM with ADH, in.dicating the monoclonality of the tumors. Twenty-four out of 26 （92.3%） cases with peri- PM and 19 specimens of normal tissue were shown to be polyclonal. In 16 cases of developed Canceration, identical X chromosome inactivation （monoclonal alterations） was observed from both the peri-PM with ADH part, and the DCIS part in each Case. CONCLUSION These results contribute to the understanding of the genetic changes of peri-PM, and confirm the peri-PM with ADH as a precancerous lesion of the breast. Clonal analysis might be a useful modality to screen high-risk cases from precancerous lesions or to distinguish between benign hyperplasia and early carcinoma.
基金This work was supported by the National Natural Science Foundation of China （No.30370553）.
文摘OBJECTIVE The aim of this research was to clone and express the antigen of the previously prepared monoclonal antibody named M4G3. METHODS Western blots were used to screen a breast cancer cell line that overexpresses the M4G3-associated antigen. A λ, zap cDNA expression library of breast cancer cells was constructed and screened using M4G3 as a probe to clone the antigen. The positive clones were subcloned and identified by homologous comparison using BLAST. RESULTS The λ zap cDNA expression library had 1.0×10^6 independent clones. Fifteen positive clones were isolated following 3 rounds of immunoscreening and identified as being from Mycoplasma pulmonis. CONCLUSION The specific antigen that matched the monoclonal M4G3 antibody is an unknown protein of M. pulmonis. This work is helpful for the further study of the association of M. pulmonis infection with breast cancer.
基金a grant from the National Natural Science Foundation of China (No. 30370553).
文摘OBJECTIVE To investigate the efficiency of gene silencing by CXCR4- siRNAs （small interfering RNA）, and to examine the invasive ability and the expression of other metastatic-associated genes in siRNA-treated breast cancer cells.METHODS Three siRNAs were designed and cloned into the pSilenc ^TM 3.1-H1 neo vector. The reconstructed plasmids were purified and transfected into the T47D breast cancer cell line, which highly expressed CXCR4. The amount of CXCR4 expression in the transfected cells was measured by flow cytometry and Real-time PCR. Cell invasive ability was evaluated using 24-well Matrigel invasion chambers. In addition, the expression of other metastatic-associated genes, such as E-cad, IGFBP-5, FN and MMP-2, was assessed by Real-time PCRRESULTS The suppression rates of CXCR4 mRNA expression reached 95.7%, 85.9% and 98.3%compared with control-siRNA cells in the 3 CXCR4- siRNA T47D cells respectively. FCM assays for CXCR4 protein expression showed a similar inhibitory effect. The invasion indexes of these CXCR4- siRNA cells were 0.037, 0.290 and 0.188 respectively compared with control- siRNA cells. After treatment of the cells with CXCR4-siRNA, the expression of E-cad showed an upward tendency and that of IGFBP-5 had a downward trend, while alteration in expression of FN and MMP2 varied without a consistant effect.CONCLUSION CXCR4 plays an important role in modulating migra- tion of human breast cancer cells. Small interfering RNA can significantly silence the CXCR4 gene in the human T47D breast cancer cell line. The results of this study strengthen the need for further research on novel gene therapy against breast cancer metastasis.
文摘OBJECTIVE Hepatocellular carcinoma （HCC） is a hypervascular tumor for which angiogenesis plays an important role in its progression, The aim of this study was to investigate the expression of TWIST and VEGF and determine their roles in angiogenesis of HCC, METHODS Expression Twist and VEGF mRNA was determined by realtime RT-PCR in 30 pairs of hepatocellular carcinoma and matched noncancerous tissues. Immunohistochemistry was carried out to analyze the protein expression of Twist and VEGF in 40 hepatocellular carcinoma cases. Staining of endothelial cells for CD34 was used to evaluate the microvessel density （MVD）. RESULTS We found that the HCC specimens showing positive Twist expression in tumor cells had a higher microvessel density than those without Twist expression. Furthermore, we found that overexpression of the Twist protein positively correlated with up-regulation of VEGF in the HCC tissues （r=0.479, P=0,002）. CONCLUSION Qur results demonstrate that Twist may play an important role in the angiogenesis of HCC and a high-level of Twist expression may be related to the malignant potential of tumor cells,
基金This work was supported by grants fromTianjin Education Commission, China(No.20040217).
文摘OBJECTIVE To investigate the effect of proteasome inhibition on the sensitivity of carcinoma cells to TRAIL-inducing apoptosis, and to study the mechanism of the response. METHODS Human hepatocellular carcinoma cells, pretreated with the proteasome inhibitor, MG132, were cotreated with TRAIL. Western blot assays, immunoprecipitation and RT-PCR were performed to test the expression of the Bcl-2 family proteins and Bax mRNA. RESULTS We found that (i) proteasome inhibition sensitized the human hepatocellular carcinoma cells to TRAIL; and (ii) resulted in Bax accumulation before release of cytochrome C and induction of apoptosis. These results were associated with the ability of proteasome inhibitors to overcome Bcl-2-mediated antiapoptotic function; (iii) Bax is regulated by an ubiquitin/proteasome-dependent degradation pathway. CONCLUSION Proteasome inhibition sensitized hepatocellular carcinoma cells to TRAIL by the inhibition of the ubiquitin/proteasome-mediated Bax degradation pathway.
基金supported by the National Natural Science Foundation of China(Grant Nos.42074224 and 12071166)the Key Research Program of the Chinese Academy of Science(Grant No.ZDRE-KT-2021-3)the Pandeng Program of National Space Science Center,Chinese Academy of Science.
文摘Coronal mass ejections(CMEs)are one of the major disturbance sources of space weather.Therefore,it is of great significance to determine whether CMEs will reach the earth.Utilizing the method of logistic regression,we first calculate and analyze the correlation coefficients of the characteristic parameters of CMEs.These parameters include central position angle,angular width,and linear velocity,which are derived from the Large Angle and Spectrometric Coronagraph(LASCO)images.We have developed a logistic regression model to predict whether a CME will reach the earth,and the model yields an F1 score of 30%and a recall of 53%.Besides,for each CME,we use the recommendation algorithm to single out the most similar historical event,which can be a reference to forecast CMEs geoeffectiveness forecasting and for comparative analysis.
