Objective： To study the effects of apigenin on vascular endothelial growth factor （VEGF） in human breast cancer cells （MDA-MB-231. Methods： MTT assay was used to detect the cell proliferation inhibitory effect of...Objective： To study the effects of apigenin on vascular endothelial growth factor （VEGF） in human breast cancer cells （MDA-MB-231. Methods： MTT assay was used to detect the cell proliferation inhibitory effect of apigenin on MDA-MB-231 cell. ELISA was used to determine the protein level of VEGF secreted by MDA-MB-231 cells. RT-PCR was used to detect mRNA levels of VEGF in MDA-MB-231 cells. The protein levels of HIF-1α, p-AKT, p-ERK1/2, and p53 were detected by Western Blotting. Results： Apigenin did not inhibit the cell viability of MDA-MB-231 cell. Apigenin reduced the secretion and mRNA levels of VEGF in MDA-MB-231 cells. Additionally, apigenin decreased the expressions of HIF-1α, p-AKT and p-ERK1/2, but induced the expression of p53. Conclusion： Apigenin can inhibit VEGF expression in human breast cancer cells, and this may be achieved through decreasing HIF-1α.展开更多
Hypoxia-induced factor-1 alpha （HIF-1α） affects many effector molecules and regulates tumor lymphangio- genesis and angiogenesis during hypoxia. The aim of this study was to investigate the role of HIF-1α in the r...Hypoxia-induced factor-1 alpha （HIF-1α） affects many effector molecules and regulates tumor lymphangio- genesis and angiogenesis during hypoxia. The aim of this study was to investigate the role of HIF-1α in the regu- lation of vascular endothelial growth factor C （VEGF-C） expression and its effect on lymphangiogenesis and an- giogenesis in breast cancer. Lymphatic vessel density （LVD）, microvessel density （MVD） and the expressions of HIF-1α and VEGF-C proteins were evaluated by immunohistochemistry in 75 breast cancer samples. There was a significant correlation between HIF-1α and VEGF-C （P = 0.014, r = 0.273, Spearman＇s coefficient of correlation）. HIF-1α and VEGF-C overexpression was significantly correlated with higher LVD （P = 0.003 and P = 0.017, re- spectively）, regional lymph nodal involvement （P = 0.002 and P = 0.004, respectively） and advanced tumor, node, metastasis （TNM） classification （P = 0.001 and P = 0.01, respectively）. Higher MVD was observed in the group expressing higher levels of HIF-1α and VEGF-C （P = 0.033 and P = 0.037, respectively）. Univariate analysis showed shorter survival time in patients expressing higher levels of HIF-1α and VEGF-C. HIF-1α was also found to be an independent prognostic factor of overall survival in multivariate analysis. The results suggest that HIF-1α may affect VEGF-C expression, thus acting as a crucial regulator of lymphangiogenesis and angiogenesis in breast cancer. This study highlights promising potential of HIF- 1α as a therapeutic target against tumor lymph node me- tastasis.展开更多
Pyruvate dehydrogenase kinase 1(PDK1)phosphorylates the pyruvate dehydroge-nase complex,which inhibits its activity.Inhibiting pyruvate dehydrogenase complex inhibits the tricarboxylic acid cycle and the reprogramming...Pyruvate dehydrogenase kinase 1(PDK1)phosphorylates the pyruvate dehydroge-nase complex,which inhibits its activity.Inhibiting pyruvate dehydrogenase complex inhibits the tricarboxylic acid cycle and the reprogramming of tumor cell metabolism to glycolysis,which plays an important role in tumor progression.This study aims to elucidate how PDK1 pro-motes breast cancer progression.We found that PDK1 was highly expressed in breast cancer tissues,and PDK1 knockdown reduced the proliferation,migration,and tumorigenicity of breast cancer cells and inhibited the HIF-1α(hypoxia-inducible factor 1α)pathway.Further investigation showed that PDK1 promoted the protein stability of HIF-1αby reducing the level of ubiquitination of HIF-1α.The HIF-1αprotein levels were dependent on PDK1 kinase activity.Furthermore,HIF-1αphosphorylation at serine 451 was detected in wild-type breast cancer cells but not in PDK1 knockout breast cancer cells.The phosphorylation of HIF-1αat Ser 451 stabilized its protein levels by inhibiting the interaction of HIF-1αwith von Hippel-Lindau and prolyl hydroxylase domain.We also found that PDK1 enhanced HIF-1αtranscriptional ac-tivity.In summary,PDK1 enhances HIF-1αprotein stability by phosphorylating HIF-1αat Ser451 and promotes HIF-1αtranscriptional activity by enhancing the binding of HIF-1αto P300.PDK1 and HIF-1αform a positive feedback loop to promote breast cancer progression.展开更多
Accumulating evidence has shown that the hypoxic microenvironment, which is critical during cancer development, plays a key role in regulating breast cancer progression and metastasis. The effects of hypoxia-inducible...Accumulating evidence has shown that the hypoxic microenvironment, which is critical during cancer development, plays a key role in regulating breast cancer progression and metastasis. The effects of hypoxia-inducible factor 1 （HIF-1）, a master regulator of the hypoxic response, have been extensively studied during these processes. In this review, we focus on the roles of HIF-1 in regulating breast cancer cell metastasis, specifically its effects on multiple key steps of metastasis, such as epithelial-mesenchymal transition （EMT）, invasion, extravasation, and metastatic niche formation. We also discuss the roles of HIF-l-regulated non-coding RNAs in breast cancer metastasis, and therapeutic opportunities for breast cancer through targeting the HIF-1 pathway,展开更多
The hypoxic model to simulate hypoxic microenvironment in solid tumors was established and the effect of hydrocamptothecin （HCPT） on the hypoxia-induced over-expression of HIF-1α and VEGF genes was explored. Human ...The hypoxic model to simulate hypoxic microenvironment in solid tumors was established and the effect of hydrocamptothecin （HCPT） on the hypoxia-induced over-expression of HIF-1α and VEGF genes was explored. Human cervical cancer SiHa cells were cultured in vitro under hypoxic conditions （37℃, 5% CO2, 1%O2） and treated with different concentrations of HCPT for 24 h. The mRNA and protein expression levels of HIF-1α, VEGF and Glutl in SiHa cells were detected by semi-quantitative RT-PCR and Western blot respectively. Normoxic control groups were exposed to normoxic conditions for 24 h. Under normoxic conditions, HCPT had no obvious effects on the HIF-1α and VEGF gene expression. Hypoxia induced the up-regulation of HIF-1α protein and downstream VEGF gene, and HCPT showed a dose-dependently inhibitory effect on the hypoxia-induced over-expression of HIF-1α protein and VEGF gene expression in SiHa cells, whereas HCPT had no significant effect on the HIF-1α mRNA expression. No difference in HCPT cytotoxic- ity was observed between hypoxic groups and normoxic control groups. It was suggested that HCPT could inhibite the expression of HIF-1α protein and downstream VEGF gene in hypoxic SiHa cells in a dose-dependent manner, and the inhibitory effect was not related with HCPT cytotoxicity.展开更多
Objective:To investigate the expression of UCH-L3 and HIF-1αin breast cancer,cancer adjacent tissues and benign lesions and their relationships with the clinicopathological characteristics.Methods:Immunohistochemistr...Objective:To investigate the expression of UCH-L3 and HIF-1αin breast cancer,cancer adjacent tissues and benign lesions and their relationships with the clinicopathological characteristics.Methods:Immunohistochemistry(IHC)method was used to detect the expression of UCH-L3 and HIF-1ɑin 99 cases with breast cancer,38 cases with cancer adjacent tissues and 29 cases with benign lesions.Results:(1)The positive expression rate of UCH-L3 in breast cancer tissue was significantly lower than that in the cancer adjacent tissues,and the expression intensity was significantly weaker than that in cancer adjacent tissues and benign lesion tissue(P<0.05).(2)The basal cell like subtype was significantly lower than that of luminal A subtype(P<0.05).(3)The expression intensity of UCH-L3 in breast cancer was positively correlated with ER and PR expression(P<0.05).(4)The nuclear expression rate of HIF-1αin the breast cancer was significantly higher than that in the cancer adjacent tissues and benign lesions.In luminal typing,the nuclear expression rate of HIF-1αin the HER2 overexpression subtype and basal cell like subtype was significantly higher than that of luminal A and B;The intensity of nuclear expression was positively correlated with Ki-67 expression proportion and histological grade,and negatively correlated with ER and PR protein expression(P<0.05).(5)The rate of HIF-1αcytoplasmic expression in the breast cancer was significantly higher than that in the cancer adjacent tissues.According to the Luminal Type,the basal cell like subtype was significantly lower than that in luminal A/B and HER2 overexpression subtype.The expression intensity was negatively correlated with Ki-67 and histological grade,and positively correlated with ER,PR and UCH-L3 expression intensity(P<0.05).Conclusions:Lost expression of UCH-L3 and overexpression of HIF-1αmight play a role in the oncogenesis and the development of breast cancer.The transformation of HIF-1αfrom cytoplasm into nucleus indicates the malignant evolution of tumor.UCH-L3 and HIF-1αhave certain value in the prognosis evaluation of breast cancer.To increase the expression of UCHL3 and to prevent the migration of HIF-1αfrom cytoplasm to nucleus may be helpful for the prevention and treatment of breast cancer,especially for basal cell like breast cancer.展开更多
Objective:Cervical cancer has become a major public health problem.The development of effective,systemic therapies for cervical cancer is highly desired.We show here that hypoxia inducible factor-1α(HIF-1α) was indi...Objective:Cervical cancer has become a major public health problem.The development of effective,systemic therapies for cervical cancer is highly desired.We show here that hypoxia inducible factor-1α(HIF-1α) was indicated as an attractive therapeutic molecular target for cervical cancer.Methods:Firstly,we observed the expressional level of HIF-1α in cervical cancer and Hela and Siha cell lines.Secondly,by constructuring HIF-1α shRNA targeting human HIF-1α mRNA common sequence and transfecting it with plasmid to cervical cell,we detected the changes of HIF-1α and its downstream genes levels VEGF.Then we injected selected stably transfected cell line into athymic nude mice to estimate its' antitumor effects.Results:We observed that HIF-1α inhibition was related to down-regulated VEGF resulting in prevention of angiogenesis,then leading to slower-growing tumors.Conclusion:The underlying concept of transfecting a HIF-1α shRNA expression vector to block the HIF-1α holds promise as the clinical potential of gene therapy for cervical cancer.展开更多
文摘Objective： To study the effects of apigenin on vascular endothelial growth factor （VEGF） in human breast cancer cells （MDA-MB-231. Methods： MTT assay was used to detect the cell proliferation inhibitory effect of apigenin on MDA-MB-231 cell. ELISA was used to determine the protein level of VEGF secreted by MDA-MB-231 cells. RT-PCR was used to detect mRNA levels of VEGF in MDA-MB-231 cells. The protein levels of HIF-1α, p-AKT, p-ERK1/2, and p53 were detected by Western Blotting. Results： Apigenin did not inhibit the cell viability of MDA-MB-231 cell. Apigenin reduced the secretion and mRNA levels of VEGF in MDA-MB-231 cells. Additionally, apigenin decreased the expressions of HIF-1α, p-AKT and p-ERK1/2, but induced the expression of p53. Conclusion： Apigenin can inhibit VEGF expression in human breast cancer cells, and this may be achieved through decreasing HIF-1α.
基金supported in part by the National Natural Science Foundation of China(No.81071753)
文摘Hypoxia-induced factor-1 alpha （HIF-1α） affects many effector molecules and regulates tumor lymphangio- genesis and angiogenesis during hypoxia. The aim of this study was to investigate the role of HIF-1α in the regu- lation of vascular endothelial growth factor C （VEGF-C） expression and its effect on lymphangiogenesis and an- giogenesis in breast cancer. Lymphatic vessel density （LVD）, microvessel density （MVD） and the expressions of HIF-1α and VEGF-C proteins were evaluated by immunohistochemistry in 75 breast cancer samples. There was a significant correlation between HIF-1α and VEGF-C （P = 0.014, r = 0.273, Spearman＇s coefficient of correlation）. HIF-1α and VEGF-C overexpression was significantly correlated with higher LVD （P = 0.003 and P = 0.017, re- spectively）, regional lymph nodal involvement （P = 0.002 and P = 0.004, respectively） and advanced tumor, node, metastasis （TNM） classification （P = 0.001 and P = 0.01, respectively）. Higher MVD was observed in the group expressing higher levels of HIF-1α and VEGF-C （P = 0.033 and P = 0.037, respectively）. Univariate analysis showed shorter survival time in patients expressing higher levels of HIF-1α and VEGF-C. HIF-1α was also found to be an independent prognostic factor of overall survival in multivariate analysis. The results suggest that HIF-1α may affect VEGF-C expression, thus acting as a crucial regulator of lymphangiogenesis and angiogenesis in breast cancer. This study highlights promising potential of HIF- 1α as a therapeutic target against tumor lymph node me- tastasis.
基金supported by grants from the National Natural Science Foundation of China(No.82073255)the Foundation of Chongqing Municipal Education Commission(China)(No.HZ2021006).
文摘Pyruvate dehydrogenase kinase 1(PDK1)phosphorylates the pyruvate dehydroge-nase complex,which inhibits its activity.Inhibiting pyruvate dehydrogenase complex inhibits the tricarboxylic acid cycle and the reprogramming of tumor cell metabolism to glycolysis,which plays an important role in tumor progression.This study aims to elucidate how PDK1 pro-motes breast cancer progression.We found that PDK1 was highly expressed in breast cancer tissues,and PDK1 knockdown reduced the proliferation,migration,and tumorigenicity of breast cancer cells and inhibited the HIF-1α(hypoxia-inducible factor 1α)pathway.Further investigation showed that PDK1 promoted the protein stability of HIF-1αby reducing the level of ubiquitination of HIF-1α.The HIF-1αprotein levels were dependent on PDK1 kinase activity.Furthermore,HIF-1αphosphorylation at serine 451 was detected in wild-type breast cancer cells but not in PDK1 knockout breast cancer cells.The phosphorylation of HIF-1αat Ser 451 stabilized its protein levels by inhibiting the interaction of HIF-1αwith von Hippel-Lindau and prolyl hydroxylase domain.We also found that PDK1 enhanced HIF-1αtranscriptional ac-tivity.In summary,PDK1 enhances HIF-1αprotein stability by phosphorylating HIF-1αat Ser451 and promotes HIF-1αtranscriptional activity by enhancing the binding of HIF-1αto P300.PDK1 and HIF-1αform a positive feedback loop to promote breast cancer progression.
基金supported partially by the National Basic Research Program(973)of China(Nos.2014CB910604 and 2012CB910104)the National Natural Science Foundation of China(Nos.31171358 and 31371429)+2 种基金the Research Fund for the Doctoral Program of Higher Education of China(No.20133402110020)the Fundamental Research Funds for the Central Universities in Chinathe ‘1000 Youth Talent Program’ by the Chinese Government for Hua-feng ZHANG
文摘Accumulating evidence has shown that the hypoxic microenvironment, which is critical during cancer development, plays a key role in regulating breast cancer progression and metastasis. The effects of hypoxia-inducible factor 1 （HIF-1）, a master regulator of the hypoxic response, have been extensively studied during these processes. In this review, we focus on the roles of HIF-1 in regulating breast cancer cell metastasis, specifically its effects on multiple key steps of metastasis, such as epithelial-mesenchymal transition （EMT）, invasion, extravasation, and metastatic niche formation. We also discuss the roles of HIF-l-regulated non-coding RNAs in breast cancer metastasis, and therapeutic opportunities for breast cancer through targeting the HIF-1 pathway,
文摘The hypoxic model to simulate hypoxic microenvironment in solid tumors was established and the effect of hydrocamptothecin （HCPT） on the hypoxia-induced over-expression of HIF-1α and VEGF genes was explored. Human cervical cancer SiHa cells were cultured in vitro under hypoxic conditions （37℃, 5% CO2, 1%O2） and treated with different concentrations of HCPT for 24 h. The mRNA and protein expression levels of HIF-1α, VEGF and Glutl in SiHa cells were detected by semi-quantitative RT-PCR and Western blot respectively. Normoxic control groups were exposed to normoxic conditions for 24 h. Under normoxic conditions, HCPT had no obvious effects on the HIF-1α and VEGF gene expression. Hypoxia induced the up-regulation of HIF-1α protein and downstream VEGF gene, and HCPT showed a dose-dependently inhibitory effect on the hypoxia-induced over-expression of HIF-1α protein and VEGF gene expression in SiHa cells, whereas HCPT had no significant effect on the HIF-1α mRNA expression. No difference in HCPT cytotoxic- ity was observed between hypoxic groups and normoxic control groups. It was suggested that HCPT could inhibite the expression of HIF-1α protein and downstream VEGF gene in hypoxic SiHa cells in a dose-dependent manner, and the inhibitory effect was not related with HCPT cytotoxicity.
基金National natural science foundation of China(No.81360395)。
文摘Objective:To investigate the expression of UCH-L3 and HIF-1αin breast cancer,cancer adjacent tissues and benign lesions and their relationships with the clinicopathological characteristics.Methods:Immunohistochemistry(IHC)method was used to detect the expression of UCH-L3 and HIF-1ɑin 99 cases with breast cancer,38 cases with cancer adjacent tissues and 29 cases with benign lesions.Results:(1)The positive expression rate of UCH-L3 in breast cancer tissue was significantly lower than that in the cancer adjacent tissues,and the expression intensity was significantly weaker than that in cancer adjacent tissues and benign lesion tissue(P<0.05).(2)The basal cell like subtype was significantly lower than that of luminal A subtype(P<0.05).(3)The expression intensity of UCH-L3 in breast cancer was positively correlated with ER and PR expression(P<0.05).(4)The nuclear expression rate of HIF-1αin the breast cancer was significantly higher than that in the cancer adjacent tissues and benign lesions.In luminal typing,the nuclear expression rate of HIF-1αin the HER2 overexpression subtype and basal cell like subtype was significantly higher than that of luminal A and B;The intensity of nuclear expression was positively correlated with Ki-67 expression proportion and histological grade,and negatively correlated with ER and PR protein expression(P<0.05).(5)The rate of HIF-1αcytoplasmic expression in the breast cancer was significantly higher than that in the cancer adjacent tissues.According to the Luminal Type,the basal cell like subtype was significantly lower than that in luminal A/B and HER2 overexpression subtype.The expression intensity was negatively correlated with Ki-67 and histological grade,and positively correlated with ER,PR and UCH-L3 expression intensity(P<0.05).Conclusions:Lost expression of UCH-L3 and overexpression of HIF-1αmight play a role in the oncogenesis and the development of breast cancer.The transformation of HIF-1αfrom cytoplasm into nucleus indicates the malignant evolution of tumor.UCH-L3 and HIF-1αhave certain value in the prognosis evaluation of breast cancer.To increase the expression of UCHL3 and to prevent the migration of HIF-1αfrom cytoplasm to nucleus may be helpful for the prevention and treatment of breast cancer,especially for basal cell like breast cancer.
文摘Objective:Cervical cancer has become a major public health problem.The development of effective,systemic therapies for cervical cancer is highly desired.We show here that hypoxia inducible factor-1α(HIF-1α) was indicated as an attractive therapeutic molecular target for cervical cancer.Methods:Firstly,we observed the expressional level of HIF-1α in cervical cancer and Hela and Siha cell lines.Secondly,by constructuring HIF-1α shRNA targeting human HIF-1α mRNA common sequence and transfecting it with plasmid to cervical cell,we detected the changes of HIF-1α and its downstream genes levels VEGF.Then we injected selected stably transfected cell line into athymic nude mice to estimate its' antitumor effects.Results:We observed that HIF-1α inhibition was related to down-regulated VEGF resulting in prevention of angiogenesis,then leading to slower-growing tumors.Conclusion:The underlying concept of transfecting a HIF-1α shRNA expression vector to block the HIF-1α holds promise as the clinical potential of gene therapy for cervical cancer.
