Background:We previously found that overexpression of the gene known as amplified in breast cancer 1(AIB1)was associated with lymph node metastasis and poor prognosis in patients with lung adenocarcinoma.However,the r...Background:We previously found that overexpression of the gene known as amplified in breast cancer 1(AIB1)was associated with lymph node metastasis and poor prognosis in patients with lung adenocarcinoma.However,the role of AIB1 in that malignancy remains unknown.The present study aimed to investigate the function of AIB1 in the process of lung adenocarcinoma cell metastasis.Methods:A series of in vivo and in vitro assays were performed to elucidate the function of AIB1,while real-time PCR and Western blotting were utilized to identify the potential downstream targets of AIB1 in the process of lung adenocarcinoma metastasis.Rescue experiments and in vitro assays were performed to investigate whether the invasive-ness of AIB1-induced lung adenocarcinoma was mediated by C-X-C motif chemokine receptor 4(CXCR4).Results:The ectopic overexpression of AIB1 in lung adenocarcinoma cells substantially enhanced cell migration and invasive abilities in vitro and tumor metastasis in vivo,whereas the depletion of AIB1 expression substantially inhibited lung adenocarcinoma cell migration and invasion.CXCR4 was identified as a potential downstream target of AIB1 in lung adenocarcinoma.The knockdown of AIB1 greatly reduced CXCR4 gene expression at both the transcription and protein levels,whereas the knockdown of CXCR4 in cells with AIB1 ectopic overexpression diminished AIB1-induced migration and invasion in vitro and tumor metastasis in vivo.Furthermore,we found a significant positive association between the expression of AIB1 and CXCR4 in lung adenocarcinoma patients(183 cases),and the co-overexpression of AIB1 and CXCR4 predicted the poorest prognosis.Conclusions:These findings suggest that AIB1 promotes the aggressiveness of lung adenocarcinoma in vitro and in vivo by upregulating CXCR4 and that it might be usable as a novel prognostic marker and/or therapeutic target for this disease.展开更多
3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole(YC-1),the hypoxia-inducible factor-1 alpha(HIF-1α) inhibitor,suppresses tumor proliferation and metastasis by down-regulating HIF-1α expression under hypoxic c...3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole(YC-1),the hypoxia-inducible factor-1 alpha(HIF-1α) inhibitor,suppresses tumor proliferation and metastasis by down-regulating HIF-1α expression under hypoxic conditions.Our previous studies demonstrated that YC-1 inhibited breast cancer cell proliferation under normoxic conditions.In the current study,we investigated the targets of YC-1 and mechanism of its action in MDA-MB-468 breast cancer cells.In the in vitro experiments,we found that YC-1 significantly inhibited MDA-MB-468 cell proliferation in normoxia and hypoxia.Under normoxic conditions,YC-1 induced apoptosis of MDA-MB-468 cells and blocked cell cycle in the G1 phase,and these effects were possibly related to caspase 8,p21,and p27 expression.RT-PCR and Western blotting results showed that YC-1 primarily inhibited HIF-1α at the mRNA and protein levels under hypoxic conditions,but suppressed the expression of epidermal growth factor receptor(EGFR) at the mRNA and protein levels under normoxic conditions.In vivo,YC-1 prolonged survival,increased survival rate,decreased tumor size and metastasis rate,and inhibited tissue EGFR and HIF-1α expression.However,YC-1 exerted no obvious effect on body weight.These results indicate that YC-1 inhibits the proliferation of MDA-MB-468 cells by acting on multiple targets with minimal side effects.Thus,YC-1 is a promising target drug for breast cancer.展开更多
This study examined the effect of Notch-1 signaling on malignant behaviors of breast cancer cells by regulating breast cancer stem cells （BCSCs）. BCSCs were enriched by using serum-free me- dium and knocked out of N...This study examined the effect of Notch-1 signaling on malignant behaviors of breast cancer cells by regulating breast cancer stem cells （BCSCs）. BCSCs were enriched by using serum-free me- dium and knocked out of Notch-1 by using a lentiviral vector. Real-time polymerase chain reaction （RT-PCR） and Western blotting were used to detect the Notch-1 expression levels in breast cancer cell lines and BCSCs, and fl0w cytometry to detect the proportion of BCSCs in BCSC spheres. The BCSC self-renewal, migration, invasion, and tumorigenicity were examined by the tumor microsphere-forming assay and transwell assay and after xenotransplantation. The results showed that the Notch-1 silencing reduced the number of BCSC spheres, the proportion of BCSCs, and the number of cells penetrating through the transwell membrane. It also decreased the size of tumors that were implanted in the nude mice. These results suggest that Notch-1 signaling is intimately linked to the behaviors of BCSCs. Blocking Notch-1 signaling can inhibit the malignant behaviors of BCSCs, which may provide a prom- ising therapeutical approach for breast cancer.展开更多
Objective： To investigate the expression of MDR-1 P-glycoprotein（MDR-1 Pgp） in breast cancer and analyze its correlation to the biological behavior and prognosis of the disease. Methods：The expression of MDR-1 Pgp...Objective： To investigate the expression of MDR-1 P-glycoprotein（MDR-1 Pgp） in breast cancer and analyze its correlation to the biological behavior and prognosis of the disease. Methods：The expression of MDR-1 Pgp was examined in 75 cases of breast cancer patients by using three different monoclonal antibodies（JSB1, C219 and C494） with S-P immunohistochemisty. These patients were followed up for 5 years, and the correlation between MDR-1 Pgp expression, survival rate and lymph metastasis was analyzed. Results： Positive detection of MDR-1 Pgp by JSB1, C219 and C494 in 75 cases of breast cancer was 86.7%, 48% and 85.3%, respectively. MDR-1 Pgp expression was not related to ages of patients （P 〉 0.05）. JSBl-detected expression of MDR-1 Pgp was related to lymph node metastasis（P〈 0.05）; while C219 and C494 were not（P 〉 0.05）. The patients with MDR-1 Pgp expression positively detected by either two of the three antibodies, had five-year survival rate that was significantly higher than those positively detected by all the three antibodies（P 〈 0.05）. Conclusion：Three antibodies should be used simultaneously to detect MDR-1 Pgp expression in breast cancer. Positive MDR-1 Pgp expression in breast cancer detected by all the three antibodies may represent a poor prognosis; while positive MDR-1 Pgp detection by JSB1 and C494 is associated with lymph metastasis.展开更多
Hypermethylation in the promoter region of tumor suppressor genes is a common mechanism of gene silencing, which tends to occur in cancer. The effects of 5-Aza-2＇-deoxycytidine （5-Aza-CdR）, a specific DNA methyltra...Hypermethylation in the promoter region of tumor suppressor genes is a common mechanism of gene silencing, which tends to occur in cancer. The effects of 5-Aza-2＇-deoxycytidine （5-Aza-CdR）, a specific DNA methyltransferase inhibitor, on the cell proliferation of human breast cancer cell line MCF-7 and on the expression of Apaf-1 gene were investigated. Human MCF-7 cells were incubated with increasing concentrations of 5-Aza-CdR for 12 to 120 h. The growth inhibition rates of MCF-7 cells were detected by MTT assay. Changes of cell cycle distribution and apoptotic rates of MCF-7 cells were determined by flow cytometry. The expressions of DNA methyltransferase 3b mRNA and Apaf-1 mRNA were measured by reverse transcription polymerase chain reaction （RT-PCR）. Meanwhile, the expression of Apaf-1 protein was detected by Western blotting. The results showed that 5-Aza-CdR significantly inhibited the growth of MCF-7 cells and the growth inhibition rate of MCF-7 cells was significantly enhanced with the concentration of 5-Aza-CdR and the action time. Flow cytometry indicated that 5-Aza-CdR could significantly induce G1/S cell cycle arrest and increase the apoptosis rate of MCF-7 cells. The mRNA and protein expressions of Apaf-1 were up-regulated in MCF-7 cells treated with 5-Aza-CdR, which was accompanied by down-regulation of DNA methyltransferase 3b mRNA. It is concluded that 5-Aza-CdR might retard the growth of tumor ceils and promote the apoptosis of MCF-7 breast cancer cells by inhibiting the expression of DNA methyltransferase 3b and re-activating the Apaf-1 gene expression.展开更多
Objective： To investigate the effects and mechanisms of trastuzumab on Notch-1 pathway in breast cancer cells, recognizing the significance of Notch-1 signaling pathway in trastuzumab resistance. Methods： Immunocyto...Objective： To investigate the effects and mechanisms of trastuzumab on Notch-1 pathway in breast cancer cells, recognizing the significance of Notch-1 signaling pathway in trastuzumab resistance. Methods： Immunocytochemistry staining and Western blotting were employed to justify the expression of Notch-1 protein in HER2-overexpressing SK-BR3 cells and HER2-non-overexpressing breast cancer MDA-MB-231 cells. Western blotting and reverse transcription PCR （RT-PCR） were used to detect the activated Notch-1 and Notch-1 target gene HES-1 mRNA expression after SK-BR3 cells were treated with trastuzumab. Double immunofluorescence staining and co-immunoprecipitation were used to analyze the relationship of Notch-1 and HER2 proteins. Results： The level of Notch-1 nuclear localization and activated Notch-1 proteins in HER2-overexpressing cells were significantly lower than in HER2-non-overexpressing cells （P0.01）, and the expressions of activated Notch-1 and HES-1 mRNA were obviously increased after trastuzumab treatment （P0.05）, but HER2 expression did not change significantly for trastuzumab treating （P0.05）. Moreover, Notch-1 was discovered to co-localize and interact with HER2 in SK-BR3 cells. Conclusion： Overexpression of HER2 decreased Notch-1 activity by the formation of a HER2-Notch1 complex, and trastuzumab can restore the activity of Notch-1 signaling pathway, which could be associated with cell resistance to trastuzumab.展开更多
The hedgehog （Hh） signaling pathway plays an essential role in the embryonic development and homeostasis of diverse adult tissues, and its deregulation has been implicated in the tumorigenesis and metastasis of vari...The hedgehog （Hh） signaling pathway plays an essential role in the embryonic development and homeostasis of diverse adult tissues, and its deregulation has been implicated in the tumorigenesis and metastasis of various malignancies including breast cancer. Aberrant activation of the Hh pathway includes the following mechanisms： （I） Hh ligand-independent mechanism - Loss of function mutations in the Hh receptor Patched 1 （PTCH1） or gain of function mutations in the Smoothened （SMO） lead to constitutive activation of this pathway; （II） Autocrine signaling- Ith ligand produced by tumor cells stimulates the Hh signaling in tumor cells; （III） Paracrine signaling - tumor cell produced-Hh ligand activates stromal and endothelial cells that produce growth factors in microenvironment for supporting tumor growth and survival; and （IV） Reverse paracrine signaling - Hh ligand produced by stromal cells support tumor growth and survival. Upon the pathway activation, the Gli transcription factors, effectors of the Hh signaling, activate or inhibit transcription by binding to their responsive genes and interacting with the transcriptional complex. The Gli transcription factor family includes Glil, Gli2, and Gli3 （1）. Glil is a transcriptional activator whose expression has been recognized as an activation state of the Hh signaling pathway, Gli2 is either an activator or repressor, and Gli3 is a strong repressor of transcriptional activities. To date, a ligand-dependent autocrine model of activating the Hh signaling has been described in breast cancer, and both an autocrine and paracrine mechanisms in colorectal cancer, pancreatic cancer and prostate cancer （2,3）. Notably, a ligand-independent mechanism （mutationsin PTCHI and SMO） of the signaling has been well demonstrated in basal cell carcinoma and medulloblastoma （4,5）.展开更多
Objective：Menage a trois 1（MAT1）is a targeting subunit of cyclin-dependent kinase-activating kinase and general transcription factor IIH kinase,which modulates cell cycle,transcription and DNA repair.Its dysregulat...Objective：Menage a trois 1（MAT1）is a targeting subunit of cyclin-dependent kinase-activating kinase and general transcription factor IIH kinase,which modulates cell cycle,transcription and DNA repair.Its dysregulation is responsible for diseases including cancers.To further explore the role of MAT1 in breast cancer,we investigated the pathways in which MAT1 might be involved,the association between MAT1 and molecular subtypes,and the role of MAT1 in clinical outcomes of breast cancer patients.Methods：We conducted immunohistochemistry staining on tissue microarray and immunofluorescence staining on sections of MAT1 stable breast cancer cells.Also,we performed Kyoto Encyclopedia of Genes and Genomes pathway analysis,correlation analysis and prognosis analysis on public databases.Results：MAT1 was involved in multiple pathways including normal physiology signaling and disease-related signaling.Furthermore,MAT1 positively correlated with the protein status of estrogen receptor and progesterone receptor,and was enriched in luminal-type and human epidermal growth factor receptor 2-enriched breast cancer in comparison with basal-like subtype at both m RNA and protein levels.Correlation analysis revealed significant association between MAT1 m RNA amount and epithelial markers,mesenchymal markers,cancer stem cell markers,apoptosis markers,transcription markers and oncogenes.Consistently,the results of immunofluorescence stain indicated that MAT1 overexpression enhanced the protein abundance of epidermal growth factor receptor,vimentin,sex determining region Y-box 2 and sine oculis homeobox homolog 1.Importantly,Kaplan-Meier Plotter analysis reflected that MAT1 could serve as a prognostic biomarker predicting worse relapse-free survival and metastasis-free survival.Conclusions：MAT1 is correlated with molecular subtypes and is associated with unfavorable prognosis for breast cancer patients.展开更多
Objective: To elucidate the effect of p14ARF gene on multidrug-resistant tumor cells. Methods: We transferred a p14ARF cDNA into p53-mutated MCF-7/Adr human breast cancer cells. Results: In this report we demonstrate...Objective: To elucidate the effect of p14ARF gene on multidrug-resistant tumor cells. Methods: We transferred a p14ARF cDNA into p53-mutated MCF-7/Adr human breast cancer cells. Results: In this report we demonstrated for the first time that p14ARF expression was able to greatly inhibit the MCF-7/Adr cell proliferation. Furthermore, p14ARF expression resulted in decreases in MDR1 mRNA and P-glycoprotein production, which linked with the reducing resistance of MCF-7/Adr cells to doxorubicin. Conclusion: These results imply that drug resistance might be effectively reversed with the wild-type p14ARF expression in human breast cancer cells.展开更多
基金supported by grants from National Key R&D Program of China(No.2017YFC1309001)Nature Science Foundation of China(No.81201842 and No.81772483)Open Project of State Key Laboratory of Respiratory Disease of China(No.SKLRD2016OP004 and No.2007DA80154F1108).
文摘Background:We previously found that overexpression of the gene known as amplified in breast cancer 1(AIB1)was associated with lymph node metastasis and poor prognosis in patients with lung adenocarcinoma.However,the role of AIB1 in that malignancy remains unknown.The present study aimed to investigate the function of AIB1 in the process of lung adenocarcinoma cell metastasis.Methods:A series of in vivo and in vitro assays were performed to elucidate the function of AIB1,while real-time PCR and Western blotting were utilized to identify the potential downstream targets of AIB1 in the process of lung adenocarcinoma metastasis.Rescue experiments and in vitro assays were performed to investigate whether the invasive-ness of AIB1-induced lung adenocarcinoma was mediated by C-X-C motif chemokine receptor 4(CXCR4).Results:The ectopic overexpression of AIB1 in lung adenocarcinoma cells substantially enhanced cell migration and invasive abilities in vitro and tumor metastasis in vivo,whereas the depletion of AIB1 expression substantially inhibited lung adenocarcinoma cell migration and invasion.CXCR4 was identified as a potential downstream target of AIB1 in lung adenocarcinoma.The knockdown of AIB1 greatly reduced CXCR4 gene expression at both the transcription and protein levels,whereas the knockdown of CXCR4 in cells with AIB1 ectopic overexpression diminished AIB1-induced migration and invasion in vitro and tumor metastasis in vivo.Furthermore,we found a significant positive association between the expression of AIB1 and CXCR4 in lung adenocarcinoma patients(183 cases),and the co-overexpression of AIB1 and CXCR4 predicted the poorest prognosis.Conclusions:These findings suggest that AIB1 promotes the aggressiveness of lung adenocarcinoma in vitro and in vivo by upregulating CXCR4 and that it might be usable as a novel prognostic marker and/or therapeutic target for this disease.
基金supported by a grant from Jilin Province Science and Technology Development Project(No.200905198)
文摘3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole(YC-1),the hypoxia-inducible factor-1 alpha(HIF-1α) inhibitor,suppresses tumor proliferation and metastasis by down-regulating HIF-1α expression under hypoxic conditions.Our previous studies demonstrated that YC-1 inhibited breast cancer cell proliferation under normoxic conditions.In the current study,we investigated the targets of YC-1 and mechanism of its action in MDA-MB-468 breast cancer cells.In the in vitro experiments,we found that YC-1 significantly inhibited MDA-MB-468 cell proliferation in normoxia and hypoxia.Under normoxic conditions,YC-1 induced apoptosis of MDA-MB-468 cells and blocked cell cycle in the G1 phase,and these effects were possibly related to caspase 8,p21,and p27 expression.RT-PCR and Western blotting results showed that YC-1 primarily inhibited HIF-1α at the mRNA and protein levels under hypoxic conditions,but suppressed the expression of epidermal growth factor receptor(EGFR) at the mRNA and protein levels under normoxic conditions.In vivo,YC-1 prolonged survival,increased survival rate,decreased tumor size and metastasis rate,and inhibited tissue EGFR and HIF-1α expression.However,YC-1 exerted no obvious effect on body weight.These results indicate that YC-1 inhibits the proliferation of MDA-MB-468 cells by acting on multiple targets with minimal side effects.Thus,YC-1 is a promising target drug for breast cancer.
基金supported by the National Nature Science Foundation of China(No.30972935)
文摘This study examined the effect of Notch-1 signaling on malignant behaviors of breast cancer cells by regulating breast cancer stem cells （BCSCs）. BCSCs were enriched by using serum-free me- dium and knocked out of Notch-1 by using a lentiviral vector. Real-time polymerase chain reaction （RT-PCR） and Western blotting were used to detect the Notch-1 expression levels in breast cancer cell lines and BCSCs, and fl0w cytometry to detect the proportion of BCSCs in BCSC spheres. The BCSC self-renewal, migration, invasion, and tumorigenicity were examined by the tumor microsphere-forming assay and transwell assay and after xenotransplantation. The results showed that the Notch-1 silencing reduced the number of BCSC spheres, the proportion of BCSCs, and the number of cells penetrating through the transwell membrane. It also decreased the size of tumors that were implanted in the nude mice. These results suggest that Notch-1 signaling is intimately linked to the behaviors of BCSCs. Blocking Notch-1 signaling can inhibit the malignant behaviors of BCSCs, which may provide a prom- ising therapeutical approach for breast cancer.
基金This work was supported by the Science Development Foundation of the Nanjing Medical University(2006NMUZ023)The research in Dr. W. Zhang's laboratory was supported by funding from the National Research Council of Canada and a Canadian Research Program spon- sored by CIHR, HSFC, ASC and Pfizer(PG-04-0248)
文摘Objective： To investigate the expression of MDR-1 P-glycoprotein（MDR-1 Pgp） in breast cancer and analyze its correlation to the biological behavior and prognosis of the disease. Methods：The expression of MDR-1 Pgp was examined in 75 cases of breast cancer patients by using three different monoclonal antibodies（JSB1, C219 and C494） with S-P immunohistochemisty. These patients were followed up for 5 years, and the correlation between MDR-1 Pgp expression, survival rate and lymph metastasis was analyzed. Results： Positive detection of MDR-1 Pgp by JSB1, C219 and C494 in 75 cases of breast cancer was 86.7%, 48% and 85.3%, respectively. MDR-1 Pgp expression was not related to ages of patients （P 〉 0.05）. JSBl-detected expression of MDR-1 Pgp was related to lymph node metastasis（P〈 0.05）; while C219 and C494 were not（P 〉 0.05）. The patients with MDR-1 Pgp expression positively detected by either two of the three antibodies, had five-year survival rate that was significantly higher than those positively detected by all the three antibodies（P 〈 0.05）. Conclusion：Three antibodies should be used simultaneously to detect MDR-1 Pgp expression in breast cancer. Positive MDR-1 Pgp expression in breast cancer detected by all the three antibodies may represent a poor prognosis; while positive MDR-1 Pgp detection by JSB1 and C494 is associated with lymph metastasis.
文摘Hypermethylation in the promoter region of tumor suppressor genes is a common mechanism of gene silencing, which tends to occur in cancer. The effects of 5-Aza-2＇-deoxycytidine （5-Aza-CdR）, a specific DNA methyltransferase inhibitor, on the cell proliferation of human breast cancer cell line MCF-7 and on the expression of Apaf-1 gene were investigated. Human MCF-7 cells were incubated with increasing concentrations of 5-Aza-CdR for 12 to 120 h. The growth inhibition rates of MCF-7 cells were detected by MTT assay. Changes of cell cycle distribution and apoptotic rates of MCF-7 cells were determined by flow cytometry. The expressions of DNA methyltransferase 3b mRNA and Apaf-1 mRNA were measured by reverse transcription polymerase chain reaction （RT-PCR）. Meanwhile, the expression of Apaf-1 protein was detected by Western blotting. The results showed that 5-Aza-CdR significantly inhibited the growth of MCF-7 cells and the growth inhibition rate of MCF-7 cells was significantly enhanced with the concentration of 5-Aza-CdR and the action time. Flow cytometry indicated that 5-Aza-CdR could significantly induce G1/S cell cycle arrest and increase the apoptosis rate of MCF-7 cells. The mRNA and protein expressions of Apaf-1 were up-regulated in MCF-7 cells treated with 5-Aza-CdR, which was accompanied by down-regulation of DNA methyltransferase 3b mRNA. It is concluded that 5-Aza-CdR might retard the growth of tumor ceils and promote the apoptosis of MCF-7 breast cancer cells by inhibiting the expression of DNA methyltransferase 3b and re-activating the Apaf-1 gene expression.
文摘Objective： To investigate the effects and mechanisms of trastuzumab on Notch-1 pathway in breast cancer cells, recognizing the significance of Notch-1 signaling pathway in trastuzumab resistance. Methods： Immunocytochemistry staining and Western blotting were employed to justify the expression of Notch-1 protein in HER2-overexpressing SK-BR3 cells and HER2-non-overexpressing breast cancer MDA-MB-231 cells. Western blotting and reverse transcription PCR （RT-PCR） were used to detect the activated Notch-1 and Notch-1 target gene HES-1 mRNA expression after SK-BR3 cells were treated with trastuzumab. Double immunofluorescence staining and co-immunoprecipitation were used to analyze the relationship of Notch-1 and HER2 proteins. Results： The level of Notch-1 nuclear localization and activated Notch-1 proteins in HER2-overexpressing cells were significantly lower than in HER2-non-overexpressing cells （P0.01）, and the expressions of activated Notch-1 and HES-1 mRNA were obviously increased after trastuzumab treatment （P0.05）, but HER2 expression did not change significantly for trastuzumab treating （P0.05）. Moreover, Notch-1 was discovered to co-localize and interact with HER2 in SK-BR3 cells. Conclusion： Overexpression of HER2 decreased Notch-1 activity by the formation of a HER2-Notch1 complex, and trastuzumab can restore the activity of Notch-1 signaling pathway, which could be associated with cell resistance to trastuzumab.
文摘The hedgehog （Hh） signaling pathway plays an essential role in the embryonic development and homeostasis of diverse adult tissues, and its deregulation has been implicated in the tumorigenesis and metastasis of various malignancies including breast cancer. Aberrant activation of the Hh pathway includes the following mechanisms： （I） Hh ligand-independent mechanism - Loss of function mutations in the Hh receptor Patched 1 （PTCH1） or gain of function mutations in the Smoothened （SMO） lead to constitutive activation of this pathway; （II） Autocrine signaling- Ith ligand produced by tumor cells stimulates the Hh signaling in tumor cells; （III） Paracrine signaling - tumor cell produced-Hh ligand activates stromal and endothelial cells that produce growth factors in microenvironment for supporting tumor growth and survival; and （IV） Reverse paracrine signaling - Hh ligand produced by stromal cells support tumor growth and survival. Upon the pathway activation, the Gli transcription factors, effectors of the Hh signaling, activate or inhibit transcription by binding to their responsive genes and interacting with the transcriptional complex. The Gli transcription factor family includes Glil, Gli2, and Gli3 （1）. Glil is a transcriptional activator whose expression has been recognized as an activation state of the Hh signaling pathway, Gli2 is either an activator or repressor, and Gli3 is a strong repressor of transcriptional activities. To date, a ligand-dependent autocrine model of activating the Hh signaling has been described in breast cancer, and both an autocrine and paracrine mechanisms in colorectal cancer, pancreatic cancer and prostate cancer （2,3）. Notably, a ligand-independent mechanism （mutationsin PTCHI and SMO） of the signaling has been well demonstrated in basal cell carcinoma and medulloblastoma （4,5）.
基金supported by the National Natural Science Foundation of China (Grant No.81572608 and 81172422)the Wuhan Science and Technology Bureau (Grant No.2017060201010170)
文摘Objective：Menage a trois 1（MAT1）is a targeting subunit of cyclin-dependent kinase-activating kinase and general transcription factor IIH kinase,which modulates cell cycle,transcription and DNA repair.Its dysregulation is responsible for diseases including cancers.To further explore the role of MAT1 in breast cancer,we investigated the pathways in which MAT1 might be involved,the association between MAT1 and molecular subtypes,and the role of MAT1 in clinical outcomes of breast cancer patients.Methods：We conducted immunohistochemistry staining on tissue microarray and immunofluorescence staining on sections of MAT1 stable breast cancer cells.Also,we performed Kyoto Encyclopedia of Genes and Genomes pathway analysis,correlation analysis and prognosis analysis on public databases.Results：MAT1 was involved in multiple pathways including normal physiology signaling and disease-related signaling.Furthermore,MAT1 positively correlated with the protein status of estrogen receptor and progesterone receptor,and was enriched in luminal-type and human epidermal growth factor receptor 2-enriched breast cancer in comparison with basal-like subtype at both m RNA and protein levels.Correlation analysis revealed significant association between MAT1 m RNA amount and epithelial markers,mesenchymal markers,cancer stem cell markers,apoptosis markers,transcription markers and oncogenes.Consistently,the results of immunofluorescence stain indicated that MAT1 overexpression enhanced the protein abundance of epidermal growth factor receptor,vimentin,sex determining region Y-box 2 and sine oculis homeobox homolog 1.Importantly,Kaplan-Meier Plotter analysis reflected that MAT1 could serve as a prognostic biomarker predicting worse relapse-free survival and metastasis-free survival.Conclusions：MAT1 is correlated with molecular subtypes and is associated with unfavorable prognosis for breast cancer patients.
文摘Objective: To elucidate the effect of p14ARF gene on multidrug-resistant tumor cells. Methods: We transferred a p14ARF cDNA into p53-mutated MCF-7/Adr human breast cancer cells. Results: In this report we demonstrated for the first time that p14ARF expression was able to greatly inhibit the MCF-7/Adr cell proliferation. Furthermore, p14ARF expression resulted in decreases in MDR1 mRNA and P-glycoprotein production, which linked with the reducing resistance of MCF-7/Adr cells to doxorubicin. Conclusion: These results imply that drug resistance might be effectively reversed with the wild-type p14ARF expression in human breast cancer cells.
