1.Recent progress in the study on antitumor drugs targeting hypoxia-inducible factor-1.
Jing-Jian WANG ; Jing LI ; Mei-Yu GENG
Acta Pharmaceutica Sinica 2008;43(6):565-569
Hypoxia-inducible factor-1 (HIF-1), as a transcription factor, plays an important role in the adaptation to hypoxic microenvironment within tumors. It can induce a series of genes transcription that participate in angiogenesis, glucose metabolism, cell proliferation, and cell migration/invasion. Thus HIF-1 not only allows cancer cells to survive in hypoxic microenvironment, but also makes the tumor more aggressive. Moreover, HIF-1 also induces tumors to acquire resistance to chemo-/radio-therapy, and is related to poor prognosis. HIF-1 emerges gradually as a potential target to develop new antitumor drugs. This paper reviews recent progress in this field.
Amphotericin B
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pharmacology
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Animals
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Antineoplastic Agents
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pharmacology
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Echinomycin
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pharmacology
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Humans
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Hypoxia-Inducible Factor 1
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antagonists & inhibitors
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genetics
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metabolism
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Indazoles
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pharmacology
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Sirolimus
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analogs & derivatives
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pharmacology
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Topotecan
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pharmacology
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Transcription, Genetic
2.Role and mechanism of Vγ4 T cells in impaired wound healing of rapamycin-induced full-thickness skin defects in mice.
Zhong Yang LIU ; Xu CHENG ; Jing Xia ZHANG ; Jian Wen ZHANG ; Li Li GUO ; Guang Shuai LI ; Ke SHI
Chinese Journal of Burns 2022;38(5):462-470
Objective: To investigate the role and mechanism of Vγ4 T cells in impaired wound healing of rapamycin-induced full-thickness skin defects in mice. Methods: The experimental research methods were applied. Eighty-six C57BL/6J male mice (hereinafter briefly referred to as wild-type mice) aged 8-12 weeks were selected for the following experiments. Vγ4 T cells were isolated from axillary lymph nodes of five wild-type mice for the following experiments. Intraperitoneal injection of rapamycin for 42 mice was performed to establish rapamycin-treated mice model for the following experiments. Eighteen wild-type mice were divided into normal control group without any treatment, trauma only group, and trauma+CC chemokine ligand 20 (CCL20) inhibitor group according to the random number table (the same grouping method below), with 6 mice in each group. The full-thickness skin defect wound was made on the back of mice in the latter two groups (the same wound model below), and mice in trauma+CCL20 inhibitor group were continuously injected subcutaneously with CCL20 inhibitor at the wound edge for 3 days after injury. Another 6 rapamycin-treated mice were used to establish wound model as rapamycin+trauma group. On post injury day (PID) 3, the epidermal cells of the skin tissue around the wound of each trauma mice were extracted by enzyme digestion, and the percentage of Vγ4 T cells in the epidermal cells was detected by flow cytometry. In normal control group, the epidermal cells of the normal skin tissue in the back of mice were taken at the appropriate time point for detection as above. Five wild-type mice were used to establish wound models. On PID 3, the epidermal cells were extracted from the skin tissue around the wound. The cell populations were divided into Vγ4 T cells, Vγ3 T cells, and γδ negative cells by fluorescence-activated cell sorter, which were set as Vγ4 T cell group, Vγ3 T cell group, and γδ negative cell group (with cells in each group being mixed with B16 mouse melanoma cells), respectively. B16 mouse melanoma cells were used as melanoma cell control group. The expression of interleukin-22 (IL-22) mRNA in cells of each group was detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR), with the number of samples being 6. Thirty rapamycin-treated mice were used to establish wound models, which were divided into Vγ4 T cell only group and Vγ4 T cell+IL-22 inhibitor group performed with corresponding injections and rapamycin control group injected with phosphate buffer solution (PBS) immediately after injury, with 10 mice in each group. Another 10 wild-type mice were taken to establish wound models and injected with PBS as wild-type control group. Mice in each group were injected continuously for 6 days. The percentage of wound area of mice in the four groups was calculated on PID 1, 2, 3, 4, 5, and 6 after injection on the same day. Six wild-type mice and 6 rapamycin-treated mice were taken respectively to establish wound models as wild-type group and rapamycin group. On PID 3, the mRNA and protein expressions of IL-22 and CCL20 in the peri-wound epidermis tissue of mice in the two groups were detected by real-time fluorescence quantitative RT-PCR and Western blotting, respectively. The Vγ4 T cells were divided into normal control group without any treatment and rapamycin-treated rapamycin group. After being cultured for 24 hours, the mRNA and protein expressions of IL-22 of cells in the two groups were detected by real-time fluorescence quantitative RT-PCR and Western blotting, respectively, with the number of samples being 6. Data were statistically analyzed with independent sample t test, analysis of variance for repeated measurement, one-way analysis of variance, Bonferroni method, Kruskal-Wallis H test, and Wilcoxon rank sum test. Results: The percentage of Vγ4 T cells in the epidermal cells of the skin tissue around the wound of mice in trauma only group on PID 3 was 0.66% (0.52%, 0.81%), which was significantly higher than 0.09% (0.04%, 0.14%) in the epidermal cells of the normal skin tissue of mice in normal control group (Z=4.31, P<0.01). The percentages of Vγ4 T cells in the epidermal cells of the skin tissue around the wound of mice in rapamycin+trauma group and trauma+CCL20 inhibitor group on PID 3 were 0.25% (0.16%, 0.37%) and 0.24% (0.17%, 0.35%), respectively, which were significantly lower than that in trauma only group (with Z values of 2.27 and 2.25, respectively, P<0.05). The mRNA expression level of IL-22 of cells in Vγ4 T cell group was significantly higher than that in Vγ3 T cell group, γδ negative cell group, and melanoma cell control group (with Z values of 2.96, 2.45, and 3.41, respectively, P<0.05 or P<0.01). Compared with that in wild-type control group, the percentage of wound area of mice in rapamycin control group increased significantly on PID 1-6 (P<0.01), the percentage of wound area of mice in Vγ4 T cell+IL-22 inhibitor group increased significantly on PID 1 and PID 3-6 (P<0.05 or P<0.01). Compared with that in rapamycin control group, the percentage of wound area of mice in Vγ4 T cell only group decreased significantly on PID 1-6 (P<0.05 or P<0.01). Compared with that in Vγ4 T cell only group, the percentage of wound area of mice in Vγ4 T cell+IL-22 inhibitor group increased significantly on PID 3-6 (P<0.05 or P<0.01). On PID 3, compared with those in wild-type group, the expression levels of IL-22 protein and mRNA (with t values of -7.82 and -5.04, respectively, P<0.01) and CCL20 protein and mRNA (with t values of -7.12 and -5.73, respectively, P<0.01) were decreased significantly in the peri-wound epidermis tissue of mice in rapamycin group. After being cultured for 24 hours, the expression levels of IL-22 protein and mRNA in Vγ4 T cells in rapamycin group were significantly lower than those in normal control group (with t values of -7.75 and -6.04, respectively, P<0.01). Conclusions: In mice with full-thickness skin defects, rapamycin may impair the CCL20 chemotactic system by inhibiting the expression of CCL20, leading to a decrease in the recruitment of Vγ4 T cells to the epidermis, and at the same time inhibit the secretion of IL-22 by Vγ4 T cells, thereby slowing the wound healing rate.
Animals
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Male
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Melanoma
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Mice
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Mice, Inbred C57BL
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RNA, Messenger
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Sirolimus/pharmacology*
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T-Lymphocytes
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Wound Healing
3.The mechanism of rapamycin in promoting asthmatic regulatory T cell differentiation and function.
Hualiang JIN ; Yan ZHOU ; Limin WANG
Journal of Zhejiang University. Medical sciences 2021;50(5):621-626
To investigate the mechanism of rapamycin in promoting asthmatic regulatory T cell differentiation . Asthma model was prepared by sensitization and challenge of ovalbumin in mice. Spleen CD4CD25 T cells were sorted from the asthmatic mice and normal mice by ultrahigh speed flow cytometer, and divided into three groups. Transforming growth factor-β and interleukin-2, or combined with rapamycin (final concentration of 500 nmol/L) were given in the model group or the rapamycin group. The levels of Treg cells and CD4CD25 T cells were detected by flow cytometry. The phosphorylation level of downstream proteins of S6 and Akt in the mTORC1/2 signaling pathway were examined by Western blotting. Compared with the model group, the differentiation level of Treg cells in the rapamycin group was significantly increased, the proliferation level of CD4CD25 T cells was decreased, and the phosphorylations of the mTORC1/2 substrates, S6 protein and Akt were decreased (all <0.05). Rapamycin can promote the differentiation and function of Treg cells via inhibition of the mTORC1/2 signaling pathway.
Animals
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Asthma
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Cell Differentiation
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Mice
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Phosphorylation
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Signal Transduction
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Sirolimus/pharmacology*
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T-Lymphocytes, Regulatory
4.Preliminary Study on the Effect of Silencing Nucleostemin Com- bined with Rapamycin on Autophagy and Apoptosis of HL-60 Cells.
Ya-Qi WANG ; Xiao-Juan GAO ; Bao-Hong YUE
Journal of Experimental Hematology 2023;31(6):1629-1634
OBJECTIVE:
To investigate the effects of knocking down nucleostemin ( NS) combined with rapamycin (RAPA) on autophagy and apoptosis in HL-60 cells , and to explore its role in HL-60 cells .
METHODS:
The expression of NS protein was detected using Western blot , after transfection of HL-60 cells was achieved by the recombinant lentviral vector NS -RNAi-GV248 . Flow cytometry was used to detect changes in cells apoptosis after NS silencing/ rapamycin for 24 , 48 hours , and the expressions of NS , LC3 , p62 , BCL-2 and Bax proteins in cells were detected by Western blot.
RESULTS:
The expression of NS in HL-60 cells was successfully down-regulated by recombinant lentiviral vector. After treatment with rapamycin for 24 and 48 h , the apoptosis rate of cells in each group increased (P < 0.05) , and the apoptosis was more obvious at 48 hours . Compared with the NS silencing group or rapamycin group , after treated with NS down-regulation combined with rapamycin for 48 hours , the apoptosis of HL-60 cells was significantly increased ( P < 0.05 ) , LC3 -II/LC3 -I ratio was significantly increased ( P < 0.05 ) , p62 protein expression was significantly decreased (P < 0.05) , and BCL-2/Bax ratio was significantly decreased ( P < 0.05) .
CONCLUSION
NS down-regulation combined with rapamycin can enhance the apoptosis and autophagy of HL-60 cells , and the induction of apoptosis of HL-60 cells may be related to the expression of BCL-2 and Bax proteins .
Humans
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HL-60 Cells
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Sirolimus/pharmacology*
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bcl-2-Associated X Protein
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Autophagy
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Apoptosis
5.Proliferation of Toxoplasma gondii Suppresses Host Cell Autophagy.
Youn Jin LEE ; Hyun Ouk SONG ; Young Ha LEE ; Jae Sook RYU ; Myoung Hee AHN
The Korean Journal of Parasitology 2013;51(3):279-287
Autophagy is a process of cytoplasmic degradation of endogenous proteins and organelles. Although its primary role is protective, it can also contribute to cell death. Recently, autophagy was found to play a role in the activation of host defense against intracellular pathogens. The aims of our study was to investigate whether host cell autophagy influences Toxoplasma gondii proliferation and whether autophagy inhibitors modulate cell survival. HeLa cells were infected with T. gondii with and without rapamycin treatment to induce autophagy. Lactate dehydrogenase assays showed that cell death was extensive at 36-48 hr after infection in cells treated with T. gondii with or without rapamycin. The autophagic markers, LC3 II and Beclin 1, were strongly expressed at 18-24 hr after exposure as shown by Western blotting and RT-PCR. However, the subsequent T. gondii proliferation suppressed autophagy at 36 hr post-infection. Pre-treatment with the autophagy inhibitor, 3-methyladenine (3-MA), down-regulated LC3 II and Beclin 1. The latter was also down-regulated by calpeptin, a calpain inhibitor. Monodansyl cadaverine (MDC) staining detected numerous autophagic vacuoles (AVs) at 18 hr post-infection. Ultrastructural observations showed T. gondii proliferation in parasitophorous vacuoles (PVs) coinciding with a decline in the numbers of AVs by 18 hr. FACS analysis failed to confirm the presence of cell apoptosis after exposure to T. gondii and rapamycin. We concluded that T. gondii proliferation may inhibit host cell autophagy and has an impact on cell survival.
Anti-Bacterial Agents/pharmacology
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Apoptosis/drug effects/physiology
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Autophagy/drug effects
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HeLa Cells
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Humans
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Sirolimus/pharmacology
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Toxoplasma/*cytology/*physiology
6.Effects of low-dose photodynamic therapy on the function of human adipose mesenchymal stem cells and its mechanism.
Yang YANG ; Lei LI ; Zeng Jun YANG ; Meng Xue ZHENG ; Wei Feng HE ; Rui YIN
Chinese Journal of Burns 2022;38(9):830-838
Objective: To investigate the effects of low-dose photodynamic therapy on the proliferation, regulation, and secretion functions of human adipose mesenchymal stem cells (ADSCs) and the related mechanism, so as to explore a new method for the repair of chronic wounds. Methods: The experimental research methods were adopted. From February to April 2021, 10 patients (5 males and 5 females, aged 23 to 47 years) who underwent cutaneous surgery in the Department of Dermatology of the First Affiliated Hospital of Army Medical University (the Third Military Medical University) donated postoperative waste adipose tissue. The cells were extracted from the adipose tissue and the phenotype was identified. Three batches of ADSCs were taken, with each batch of cells being divided into normal control group with conventional culture only, photosensitizer alone group with conventional culture after being treated with Hemoporfin, irradiation alone group with conventional culture after being treated with red light irradiation, and photosensitizer+irradiation group with conventional culture after being treated with Hemoporfin and red light irradiation, with sample number of 3 in each group. At culture hour of 24 after the treatment of the first and second batches of cells, the ADSC proliferation level was evaluated by 5-ethynyl-2'-deoxyuridine staining method and the migration percentage of HaCaT cells cocultured with ADSCs was detected by Transwell experiment, respectively. On culture day of 7 after the treatment of the third batch of cells, the extracellular matrix protein expression of ADSCs was detected by immunofluorescence method. The ADSCs were divided into 0 min post-photodynamic therapy group, 15 min post-photodynamic therapy group, 30 min post-photodynamic therapy group, and 60 min post-photodynamic therapy group, with 3 wells in each group. Western blotting was used to detect the protein expressions and calculate the phosphorylated mammalian target of rapamycin complex (p-mTOR)/mammalian target of rapamycin (mTOR), phosphorylated p70 ribosomal protein S6 kinase (p-p70 S6K)/p70 ribosomal protein S6 kinase (p70 S6K) ratio at the corresponding time points after photodynamic therapy. Two batches of ADSCs were taken, and each batch was divided into normal control group, photodynamic therapy alone group, and photodynamic therapy+rapamycin group, with 3 wells in each group. At culture minute of 15 after the treatment, p-mTOR/mTOR and p-p70 S6K/p70 S6K ratios of cells from the first batch were calculated and detected as before. On culture day of 7 after the treatment, extracellular matrix protein expression of cells from the second batch was detected as before. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: After 12 d of culture, the cells were verified as ADSCs. At culture hour of 24 after the treatment, the ADSC proliferation level ((4.0±1.0)% and (4.1±0.4)%, respectively) and HaCaT cell migration percentages (1.17±0.14 and 1.13±0.12, respectively) in photosensitizer alone group and irradiation alone group were similar to those of normal control group ((3.7±0.6)% and 1.00±0.16, respectively, P>0.05), and were significantly lower than those of photosensitizer+irradiation group ((34.2±7.0)% and 2.55±0.13, respectively, P<0.01). On culture day of 7 after the treatment, compared with those in normal control group, the expression of collagen Ⅲ in ADSCs of photosensitizer alone group was significantly increased (P<0.05), and the expressions of collagen Ⅰ and collagen Ⅲ in ADSCs of irradiation alone group were significantly increased (P<0.01). Compared with those in photosensitizer alone group and irradiation alone group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photosensitizer+irradiation group were significantly increased (P<0.01). Compared with those in 0 min post-photodynamic therapy group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in 15 min post-photodynamic therapy group were significantly increased (P<0.01), the ratios of p-p70 S6K/p70 S6K of ADSCs in 30 min post-photodynamic therapy group and 60 min post-photodynamic therapy group were both significantly increased (P<0.01). At culture minute of 15 after the treatment, compared with those in normal control group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in photodynamic therapy alone group were significantly increased (P<0.05 or P<0.01). Compared with those in photodynamic therapy alone group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in photodynamic therapy+rapamycin group were significantly decreased (P<0.05). On culture day of 7 after the treatment, compared with those in normal control group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photodynamic therapy alone group were significantly increased (P<0.01). Compared with those in photodynamic therapy alone group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photodynamic therapy+rapamycin group were significantly decreased (P<0.01). Conclusions: Low-dose photodynamic therapy can promote the proliferation of ADSCs, improve the ability of ADSCs to regulate the migration of HaCaT cells, and enhance the secretion of extracellular matrix protein by rapidly activating mTOR signaling pathway.
Adipose Tissue
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Female
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Fibronectins
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Humans
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Male
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Mesenchymal Stem Cells
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Photochemotherapy
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Photosensitizing Agents/pharmacology*
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Sirolimus/pharmacology*
;
TOR Serine-Threonine Kinases
7.Increased autophagy of peripheral blood neutrophils and neutrophils extracellular traps formation in systemic lupus erythematosus.
Dongmei YANG ; Jing ZHU ; Jianbo XIAO ; Rendong HE ; Yan XING
Chinese Journal of Cellular and Molecular Immunology 2023;39(4):356-362
Objective To explore the role of autophagy, apoptosis of neutrophils and neutrophils extracellular traps (NET) formation in systemic lupus erythematosus (SLE). Methods Thirty-six patients with SLE were recruited as research subjects, and 32 healthy controls matched accordingly were enrolled as control subjects. The expression levels of microtubule associated protein 1 light chain 3B (LC3B), autophagy-related gene5(ATG5), P62, B-cell lymphoma 2(Bcl2), Bcl2-related X protein (BAX) in neutrophils were detected by Western blot analysis. Flow cytometry was employed to analyze the expression of LC3B on neutrophils. The expression level of myeloperoxidase(MPO) in plasma was estimated by ELISA. Furthermore, neutrophils were cultured in vitro and stimulated by 100 nmol/L rapamycin and 10 μg/mL lipopolysaccharide (LPS) for 6 hours, respectively. And then, the expression levels of LC3B, ATG5, P62, Bcl2 and BAX in neutrophils were detected by Western blot analysis. The level of MPO in culture supernatant was detected by ELISA. The change of fluorescence intensity of NET in culture supernatant was assayed by SytoxTM Green staining combined with fluorescence spectrophotometry. Results Compared with healthy controls, the levels of autophagy and apoptosis of neutrophils and NET formation in SLE patients were increased. The level of apoptosis and NET formation was positively associated with neutrophil autophagy. The level of autophagy showed an increase but had no effect on apoptosis and NET formation for neutrophil stimulated by rapamycin. The levels of autophagy and NET formation also increased with no significant effect on apoptosis for neutrophil induced by LPS. Conclusion The autophagy, apoptosis and NET formation of neutrophils increase in SLE patients. The activation of autophagy and NET in neutrophils possibly result from the inflammatory internal environment in SLE patients.
Humans
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Neutrophils
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Extracellular Traps/metabolism*
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Lipopolysaccharides/pharmacology*
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bcl-2-Associated X Protein/metabolism*
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Sirolimus/pharmacology*
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Lupus Erythematosus, Systemic
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Autophagy
8.Effect of chemotherapy with cisplatin and rapamycin against Hep-2 cells in vitro.
Wen-bin LEI ; Tao JIA ; Zhen-zhong SU ; Wei-ping WEN ; Xiao-lin ZHU
Journal of Southern Medical University 2008;28(10):1838-1841
OBJECTIVETo evaluate the effect of combined use of rapamycin and cisplatin in the chemotherapy of Hep-2 cells in vitro.
METHODSThe inhibitory effects of rapamycin and cisplatin, used alone or in combination, on the proliferation of Hep-2 cells were measured with MTT assay and median-effect plot analysis. The cell cycle changes after the treatment were analyzed using flow cytometry and Hoechst 33258 immunofluorescence staining.
RESULTSThe IC50 of rapamycin and cisplatin for inducing growth arrest of Hep-2 cells was 11.03 nmol/L and 8.81 micromol/L, respectively. Rapamycin alone caused cell cycle arrest of the Hep-2 cells in G1 phase. Rapamycin and cisplatin showed synergistic effects in the chemotherapy of Hep-2 cells (q > 1.15, King's Formula), causing significantly increased apoptosis ratio and growth inhibition rate of Hep-2 cells.
CONCLUSIONCombined use of rapamycin and cisplatin significantly improves the chemotherapeutic effect against Hep-2 cells.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Squamous Cell ; pathology ; Cell Proliferation ; drug effects ; Cisplatin ; pharmacology ; Drug Synergism ; Humans ; Laryngeal Neoplasms ; pathology ; Sirolimus ; pharmacology ; Tumor Cells, Cultured
9.IRE1α deficiency impairs autophagy in chondrocytes by upregulating calcium homeostasis endoplasmic reticulum protein.
Xing Yue LI ; Dan Yang YIN ; Meng Tian FAN ; Yu You YANG ; Li LIANG ; Nai Bo FENG ; Xiao Li LI ; Feng Jin GUO
Journal of Southern Medical University 2022;42(6):785-793
OBJECTIVE:
To explore the mechanism by which inositol-requiring enzyme-1α (IRE1α) regulates autophagy function of chondrocytes through calcium homeostasis endoplasmic reticulum protein (CHERP).
METHODS:
Cultured human chondrocytes (C28/I2 cells) were treated with tunicamycin, 4μ8c, rapamycin, or both 4μ8c and rapamycin, and the expressions of endoplasmic reticulum (ER) stress- and autophagy-related proteins were detected with Western blotting. Primary chondrocytes from ERN1 knockout (ERN1 CKO) mice and wild-type mice were examined for ATG5 and ATG7 mRNA expressions, IRE1α and p-IRE1α protein expressions, and intracellular calcium ion content using qPCR, Western blotting and flow cytometry. The effect of bafilomycin A1 treatment on LC3 Ⅱ/LC3 Ⅰ ratio in the isolated chondrocytes was assessed with Western blotting. Changes in autophagic flux of the chondrocytes in response to rapamycin treatment were detected using autophagy dual fluorescent virus. The changes in autophagy level in C28/I2 cells overexpressing CHERP and IRE1α were detected using immunofluorescence assay.
RESULTS:
Tunicamycin treatment significantly up-regulated ER stress-related proteins and LC3 Ⅱ/LC3 Ⅰ ratio and down-regulated the expression of p62 in C28/I2 cells (P < 0.05). Rapamycin obviously up-regulated LC3 Ⅱ/LC3 Ⅰ ratio (P < 0.001) in C28/I2 cells, but this effect was significantly attenuated by co-treatment with 4μ8c (P < 0.05). Compared with the cells from the wild-type mice, the primary chondrocytes from ERN1 knockout mice showed significantly down-regulated mRNA levels of ERN1 (P < 0.01), ATG5 (P < 0.001) and ATG7 (P < 0.001), lowered or even lost expressions of IRE1α and p-IRE1α proteins (PP < 0.01), and increased expression of CHERP (P < 0.05) and intracellular calcium ion content (P < 0.001). Bafilomycin A1 treatment obviously increased LC3 Ⅱ/ LC3 Ⅰ ratio in the chondrocytes from both wild-type and ERN1 knockout mice (P < 0.01 or 0.05), but the increment was more obvious in the wild-type chondrocytes (P < 0.05). Treatment with autophagy dual-fluorescence virus resulted in a significantly greater fluorescence intensity of LC3-GFP in rapamycin-treated ERN1 CKO chondrocytes than in wild-type chondrocytes (P < 0.05). In C28/I2 cells, overexpression of CHERP obviously decreased the fluorescence intensity of LC3, and overexpression of IRE1α enhanced the fluorescence intensity and partially rescued the fluorescence reduction of LC3 caused by CHERP.
CONCLUSION
IRE1α deficiency impairs autophagy in chondrocytes by upregulating CHERP and increasing intracellular calcium ion content.
Animals
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Autophagy
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Calcium/metabolism*
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Chondrocytes
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Endoplasmic Reticulum/metabolism*
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Endoribonucleases/pharmacology*
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Homeostasis
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Inositol
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Mice
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Mice, Knockout
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Protein Serine-Threonine Kinases
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RNA, Messenger/metabolism*
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Sirolimus/pharmacology*
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Tunicamycin/pharmacology*
10.Rapamycin enhances the anti-tumor activity of cabozantinib in cMet inhibitor-resistant hepatocellular carcinoma.
Chao GAO ; Shenghao WANG ; Weiqing SHAO ; Yu ZHANG ; Lu LU ; Huliang JIA ; Kejin ZHU ; Jinhong CHEN ; Qiongzhu DONG ; Ming LU ; Wenwei ZHU ; Lunxiu QIN
Frontiers of Medicine 2022;16(3):467-482
Cabozantinib, mainly targeting cMet and vascular endothelial growth factor receptor 2, is the second-line treatment for patients with advanced hepatocellular carcinoma (HCC). However, the lower response rate and resistance limit its enduring clinical benefit. In this study, we found that cMet-low HCC cells showed primary resistance to cMet inhibitors, and the combination of cabozantinib and mammalian target of rapamycin (mTOR) inhibitor, rapamycin, exhibited a synergistic inhibitory effect on the in vitro cell proliferation and in vivo tumor growth of these cells. Mechanically, the combination of rapamycin with cabozantinib resulted in the remarkable inhibition of AKT, extracellular signal-regulated protein kinases, mTOR, and common downstream signal molecules of receptor tyrosine kinases; decreased cyclin D1 expression; and induced cell cycle arrest. Meanwhile, rapamycin enhanced the inhibitory effects of cabozantinib on the migration and tubule formation of human umbilical vascular endothelial cells and human growth factor-induced invasion of cMet inhibitor-resistant HCC cells under hypoxia condition. These effects were further validated in xenograft models. In conclusion, our findings uncover a potential combination therapy of cabozantinib and rapamycin to combat cabozantinib-resistant HCC.
Anilides/pharmacology*
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Animals
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Carcinoma, Hepatocellular/drug therapy*
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Cell Line, Tumor
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Cell Proliferation
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Endothelial Cells/metabolism*
;
Humans
;
Liver Neoplasms/drug therapy*
;
Pyridines/pharmacology*
;
Sirolimus/pharmacology*
;
Xenograft Model Antitumor Assays