In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS...In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS).As a signal mechanism that mitigates ERS in eukaryotic cells,the unfolded protein response(UPR)pathway can activate cells and tissues,regulating pathological activities in various cells,and maintaining ER homeostasis.It forms the most crucial adaptive and defensive mechanism for cells.However,under the continuous influence of chemotherapy drugs,the quantity of unfolded proteins and erroneous proteins produced by tumor cells significantly increases,surpassing the normal regulatory range of UPR.Consequently,ERS fails to function properly,fostering tumor cell proliferation and the development of drug resistance.This review delves into the study of three UPR pathways(PERK,IRE1,and ATF6),elucidating the mechanisms of drug resistance and research progress in the signal transduction pathway of UPR related to cancers.It provides a profound understanding of the role and relationship between UPR and anti-tumor drugs,offering a new direction for effective clinical treatment.展开更多
Although the functional parameters of micro RNAs(mi RNAs)have been explored to some extent,the roles of these molecules in coronavirus infection and the regulatory mechanism of mi RNAs in virus infection are still unc...Although the functional parameters of micro RNAs(mi RNAs)have been explored to some extent,the roles of these molecules in coronavirus infection and the regulatory mechanism of mi RNAs in virus infection are still unclear.Transmissible gastroenteritis virus(TGEV)is an enteropathgenic coronavirus and causes high morbidity and mortality in suckling piglets.Here,we demonstrated that microRNA-27b-3p(miR-27b-3p)suppressed TGEV replication by directly targeting porcine suppressor of cytokine signaling 6(SOCS6),while TGEV infection downregulated miR-27b-3p expression in swine testicular(ST)cells and in piglets.Mechanistically,the decrease of miR-27b-3p expression during TGEV infection was mediated by the activated inositolrequiring enzyme 1(IRE1)pathway of the endoplasmic reticulum(ER)stress.Further studies showed that when ER stress was induced by TGEV,IRE1 acted as an RNase activated by autophosphorylation and unconventionally spliced m RNA encoding a potent transcription factor,X-box-binding protein 1(Xbp1s).Xbp1s inhibited the transcription of miR-27 and ultimately reduced the production of miR-27b-3p.Therefore,our findings indicate that TGEV inhibits the expression of an anti-coronavirus micro RNA through the IRE1 pathway and suggest a novel way in which coronavirus regulates the host cell response to infection.展开更多
Objective:To examine whether exposure of mouse neuronal cells to radiofrequency fields used in mobile communication devices can induce stress in endoplasmic reticulum(ER)and activate unfolded protein response(UPR).Met...Objective:To examine whether exposure of mouse neuronal cells to radiofrequency fields used in mobile communication devices can induce stress in endoplasmic reticulum(ER)and activate unfolded protein response(UPR).Methods:HT22 mouse hippocampus neuronal cells were exposed to continuous wave 900 MHz radiofrequency fields(RF)at 120μW/cm2 power intensity for 4 h/d for 5 consecutive days.The positive control cells were irradiated with 4 Gy of 60Coγ-rays at a dose rate of 0.5 Gy/min(GR).Twenty-four hours after the last exposure,cells were collected,and the expressions of sensor transmembrane proteins were detected using Western blot analysis.Results:The expression levels of Ire1,PERK,p-IRE1 and p-PERK,GRP78 and CHOP proteins were detected.There were no statistically significant differences in the expression levels of IRE1 and PERK proteins in control(CT),sham(SH)-,RF-and GR-exposed cells(P<0.05).The phosphorylated protein levels of p-IRE1 and p-PERK were significantly increased in cells exposed to RF and GR(P<0.05).The expression levels of GRP78 and CHOP were significantly increased in RF-and GR-exposed cells compared to CT and SH-exposed cells(P<0.05).Cells treated with 1μg/ml TM for 24 h showed significantly increased expression levels of GRP78 and CHOP proteins compared to controls(P<0.05).In the presence of 2 mmol/L PBA,TM-induced increased levels of GRP78 and CHOP proteins were reduced(P<0.05).Conclusions:The exposure of non-ionizing 900 MHz RF was able to cause stress in HT22 mouse neuronal cells and activated UPR in ER.Since UPR plays an important role in both cell survival(when UPR is mitigated)and apoptosis/death(under unresolvable stress conditions),further studies are required to determine the fate of the cells exposed to RF.展开更多
文摘In the process of tumor proliferation and metastasis,tumor cells encounter hypoxia,low glucose,acidosis,and other stressful environments.These conditions prompt tumor cells to generate endoplasmic reticulum stress(ERS).As a signal mechanism that mitigates ERS in eukaryotic cells,the unfolded protein response(UPR)pathway can activate cells and tissues,regulating pathological activities in various cells,and maintaining ER homeostasis.It forms the most crucial adaptive and defensive mechanism for cells.However,under the continuous influence of chemotherapy drugs,the quantity of unfolded proteins and erroneous proteins produced by tumor cells significantly increases,surpassing the normal regulatory range of UPR.Consequently,ERS fails to function properly,fostering tumor cell proliferation and the development of drug resistance.This review delves into the study of three UPR pathways(PERK,IRE1,and ATF6),elucidating the mechanisms of drug resistance and research progress in the signal transduction pathway of UPR related to cancers.It provides a profound understanding of the role and relationship between UPR and anti-tumor drugs,offering a new direction for effective clinical treatment.
基金supported by the Heilongjiang Postdoctoral fund(LBH-Z18207)the National Natural Science Foundation of China(31802198)+2 种基金the Fundamental Research Funds for the Provincial Universities(2018-KYYWF-0553)the National Key Research and Development Program of China(2017YFC0908001)the Spark Research Fund from the Fourth Affiliated Hospital of Harbin Medical University(HYDSYXH201914)。
文摘Although the functional parameters of micro RNAs(mi RNAs)have been explored to some extent,the roles of these molecules in coronavirus infection and the regulatory mechanism of mi RNAs in virus infection are still unclear.Transmissible gastroenteritis virus(TGEV)is an enteropathgenic coronavirus and causes high morbidity and mortality in suckling piglets.Here,we demonstrated that microRNA-27b-3p(miR-27b-3p)suppressed TGEV replication by directly targeting porcine suppressor of cytokine signaling 6(SOCS6),while TGEV infection downregulated miR-27b-3p expression in swine testicular(ST)cells and in piglets.Mechanistically,the decrease of miR-27b-3p expression during TGEV infection was mediated by the activated inositolrequiring enzyme 1(IRE1)pathway of the endoplasmic reticulum(ER)stress.Further studies showed that when ER stress was induced by TGEV,IRE1 acted as an RNase activated by autophosphorylation and unconventionally spliced m RNA encoding a potent transcription factor,X-box-binding protein 1(Xbp1s).Xbp1s inhibited the transcription of miR-27 and ultimately reduced the production of miR-27b-3p.Therefore,our findings indicate that TGEV inhibits the expression of an anti-coronavirus micro RNA through the IRE1 pathway and suggest a novel way in which coronavirus regulates the host cell response to infection.
基金This research is supported by funding from the National Natural Science Foundation of China(Grant No.81373025).
文摘Objective:To examine whether exposure of mouse neuronal cells to radiofrequency fields used in mobile communication devices can induce stress in endoplasmic reticulum(ER)and activate unfolded protein response(UPR).Methods:HT22 mouse hippocampus neuronal cells were exposed to continuous wave 900 MHz radiofrequency fields(RF)at 120μW/cm2 power intensity for 4 h/d for 5 consecutive days.The positive control cells were irradiated with 4 Gy of 60Coγ-rays at a dose rate of 0.5 Gy/min(GR).Twenty-four hours after the last exposure,cells were collected,and the expressions of sensor transmembrane proteins were detected using Western blot analysis.Results:The expression levels of Ire1,PERK,p-IRE1 and p-PERK,GRP78 and CHOP proteins were detected.There were no statistically significant differences in the expression levels of IRE1 and PERK proteins in control(CT),sham(SH)-,RF-and GR-exposed cells(P<0.05).The phosphorylated protein levels of p-IRE1 and p-PERK were significantly increased in cells exposed to RF and GR(P<0.05).The expression levels of GRP78 and CHOP were significantly increased in RF-and GR-exposed cells compared to CT and SH-exposed cells(P<0.05).Cells treated with 1μg/ml TM for 24 h showed significantly increased expression levels of GRP78 and CHOP proteins compared to controls(P<0.05).In the presence of 2 mmol/L PBA,TM-induced increased levels of GRP78 and CHOP proteins were reduced(P<0.05).Conclusions:The exposure of non-ionizing 900 MHz RF was able to cause stress in HT22 mouse neuronal cells and activated UPR in ER.Since UPR plays an important role in both cell survival(when UPR is mitigated)and apoptosis/death(under unresolvable stress conditions),further studies are required to determine the fate of the cells exposed to RF.
