1.Effect of MiR-451a on Erythroid Differentiation of K562 Cells under Hypoxia.
Cai-Yan HU ; Hui-Jie ZHANG ; Cheng-Bing FU ; Fang LIU
Journal of Experimental Hematology 2020;28(6):2071-2078
OBJECTIVE:
To investigate the changes of GATA-1 protein expression during erythroid differentiation of K562 cells under hypoxia and how GATA-1 can regulate erythroid differentiation by up-regulating the expression of miR-451a and inhibiting the expression of 14-3-3ζ.
METHODS:
K562 cells were divided into 2 groups: the normoxia group and the hypoxia group, after the induction of hemin for 96 h, the positive cells rate of the benzidine staining, the mRNA expression of γ-globin and the expression of CD235a were detected, and the success of the model was verified. The changes of GATA-1 and miR-451a expression in the above-mentioned 2 groups, the changes of miR-451a expression after over-expressed GATA-1 were detected by Western blot and qRT-PCR. The cells in normoxic group and hypoxia group were divided into negative control group (NC group) and miR-451a over-expression group respectively, and the degree of erythroid differentiation in the four groups was judged according to the corresponding erythroid differentiation indexes, and the expression of 14-3-3ζ was detected by Western blot after over-expressed miR-451a.
RESULTS:
The positive cell rate of benzidine staining, mRNA expression of γ-globin and the expression of CD235a after 96 h induction by K562 cells under hypoxia were significantly higher than 0 h, suggesting that the erythroid differentiation model of K562 cells under hypoxia was replicated successfully. The expression levels of GATA-1 protein and miR-451a in the hypoxic group were significantly higher than that in the normoxic group (P<0.05). The expression level of miR-451a in hypoxia group was significantly higher than that in NC group after overexpressed GATA-1 (P<0.05). After over-expressed of miR-451a under hypoxia, the positive cell rate of benzidine staining, the mRNA expression level of γ-globin and the expression of CD235a were significantly higher than those in NC group (P<0.05). The expression level of 14-3-3ζ protein in miR-451a over-expressed group was lower than that in NC group under hypoxia (P<0.05).
CONCLUSION
Hypoxia can significantly increase the expression of GATA-1 protein, and the increase of GATA-1 expression can up-regulate the expression of miR-451a, thereby inhibiting the expression of 14-3-3ζ protein, which hinders the cell proliferation in erythroid differentiation model of K562 cells and plays an important role in promoting erythroid differentiation.
14-3-3 Proteins
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Cell Differentiation
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Erythroid Cells/metabolism*
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GATA1 Transcription Factor/metabolism*
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Humans
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Hypoxia
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K562 Cells
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MicroRNAs/genetics*
2.Significance of Oct-4's expression in thyroid neoplasm.
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2010;24(15):682-685
OBJECTIVE:
To discuss the meanings of Oct-4's expression in thyroid adenoma, thyroid papillary carcinoma, thyroid follicular carcinoma, and medullary thyroid carcinoma.
METHOD:
We examined the expression of Oct-4 in 15 thyroid adenoma, 30 thyroid papillary carcinomas, 2 thyroid follicular carcinomas, and 3 medullary thyroid carcinomas using immunofluorescence.
RESULT:
Oct-4 expression was observed in all the thyroid-related diseases mentioned above. In thyroid papillary carcinomas, the expression of Oct-4 were higher than that in thyroid adenoma, and had no obvious relationship with the patients age, sex, the size and location of tumor and tumor metastasis.
CONCLUSION
The formation of the thyroid carcinomas may be concerned with the stem cells in thyroid. There are more stem cells in medullary thyroid carcinomas and follicular carcinomas.
Adenocarcinoma, Follicular
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metabolism
;
pathology
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Carcinoma, Neuroendocrine
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Carcinoma, Papillary
;
metabolism
;
pathology
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Humans
;
Octamer Transcription Factor-3
;
metabolism
;
Thyroid Neoplasms
;
metabolism
;
pathology
3.Expressions of ATF3 and CTGF and their regulation by estradiol in the prepuce of hypospadias patients.
Juan ZHOU ; Hao WANG ; Yu-Bing PENG ; Qi CHEN ; Jun DA ; Zhong WANG ; Li-Min MA
National Journal of Andrology 2009;15(12):1075-1080
OBJECTIVEEstrogen is closely associated with hypospadias. The present study was to explore the molecular mechanism of hypospadias caused by estradiol.
METHODSFibroblasts obtained from the prepuce of hypospadiac and normal children were cultured in vitro and treated with 17-beta ethinyl estradiol (17-EE) at the concentrations of 1 micromol/L to 0.1 nmol/L for 2 hours, or at 0.1 micromol/L for 0.5, 1, 2, 4, 8, 16 and 24 hours. MTT assay was used to evaluate the effect of 17-EE on the proliferation of the cells, and RT-PCR was employed to detect the expressions of the activating transcription factor-3 (ATF3) and connective tissue growth factor (CTGF) in the hypospadiac tissue. The results were compared with those obtained from the nonhypospadiac tissue.
RESULTSThe expressions of ATF3 and CTGF were significantly upregulated in the hypospadiac tissue as compared with the nonhypospadiac group. At the concentration of 1 micromol/L, 17-EE significantly inhibited the proliferation of the cells. ATF3 mRNA was elevated at 1-2 hours, while CTGF mRNA showed no significant changes in 24 hours.
CONCLUSIONATF3 and CTGF are two candidate genes involved in the etiology of hypospadias. And estradiol may induce hypospadias by upregulating the expressions of ATF3 and CTGF.
Activating Transcription Factor 3 ; genetics ; metabolism ; Cells, Cultured ; Child ; Connective Tissue Growth Factor ; genetics ; metabolism ; Estradiol ; pharmacology ; Estrogens ; pharmacology ; Fibroblasts ; metabolism ; Foreskin ; metabolism ; Humans ; Hypospadias ; genetics ; metabolism ; Male
4.Enhanced proliferation and differentiation of Oct4- and Sox2-overexpressing human adipose tissue mesenchymal stem cells.
Sei Myoung HAN ; Sang Hun HAN ; Ye Rin COH ; Goo JANG ; Jeong CHAN RA ; Sung Keun KANG ; Hee Woo LEE ; Hwa Young YOUN
Experimental & Molecular Medicine 2014;46(6):e101-
Mesenchymal stem cells (MSCs) are attractive candidates for clinical repair or regeneration of damaged tissues. Oct4 and Sox2, which are essential transcription factors for pluripotency and self-renewal, are naturally expressed in MSCs at low levels in early passages, and their levels gradually decrease as the passage number increases. Therefore, to improve MSC proliferation and stemness, we introduced human Oct4 and Sox2 for conferring higher expansion and differentiation capabilities. The Oct4-IRES-Sox2 vector was transfected into human adipose tissue MSCs (ATMSCs) by liposomal transfection and used directly. Oct4 and Sox2 were successfully transfected into ATMSCs, and we confirmed maintenance of MSC surface markers without alterations in both red fluorescent protein (RFP) (control) and Oct4/Sox2-ATMSCs. Enhanced proliferative activity of Oct4/Sox2-ATMSCs was shown by WST-1 assay, and this result was further confirmed by cell counting using trypan blue exclusion for a long period. In addition, FACs cell cycle analysis showed that there was a reduction in the fraction of Oct4/Sox2-ATMSCs in G1 with a concomitant increase in the fraction of cells in S, compared with RFP-ATMSCs. Increased levels of cyclin D1 were also seen in Oct4/Sox2-ATMSCs, indicating acceleration in the transition of cells from G1 to S phase. Furthermore, Oct4/Sox2-overexpressing ATMSCs showed higher differentiation abilities for adipocytes or osteoblasts than controls. The markers of adipogenic or osteogenic differentiation were also upregulated by Oct4/Sox2 overexpression. The improvement in cell proliferation and differentiation using Oct4/Sox2 expression in ATMSCs may be a useful method for expanding the population and increasing the stemness of ATMSCs.
Adipose Tissue/cytology
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*Cell Differentiation
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*Cell Proliferation
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Cells, Cultured
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Humans
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Mesenchymal Stromal Cells/cytology/*metabolism/physiology
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Octamer Transcription Factor-3/genetics/*metabolism
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SOXB1 Transcription Factors/genetics/*metabolism
5.Expression of OCT4 protein in bladder cancer and its clinicopathological implications.
Pengpeng ZHAO ; Chunxiao LIU ; Kai XU ; Shaobo ZHENG ; Hulin LI ; Yawen XU ; Abai XU ; Bingkun LI ; Peng HUANG
Journal of Southern Medical University 2012;32(5):643-646
OBJECTIVETo study the expression of OCT4 protein in bladder cancer and its correlation to the clinicopathologic features and prognosis of bladder cancer.
METHODSOCT4 mRNA and protein expression was detected in 5 bladder cancer cell lines (RT-4, Tcc-Sup, KK47, T24, and 5637) and 1 normal bladder cell lines by real-time PCR and Western blotting, respectively. Immunohistochemical analysis was used to detect the expression of OCT4 protein in 46 bladder cancer samples.
RESULTSAll the 5 bladder cancer cell lines expressed detectable levels of OCT4 mRNA and proteins, whereas the normal bladder cell line SV-HUC-1 was negative for OCT4 expression. The clinical bladder cancer tissues showed a high positivity rate of OCT4 expression (76.1%), which was not detected in normal bladder tissues. Specific OCT-4 signals were localized mainly in the nuclei of the cancer cells. The expression rate of OCT4 protein was significantly higher in bladder cancer tissue than in normal bladder epithelium (P<0.05), and showed a positive correlation to the grade of tumor differentiation and metastasis (P<0.05) but not to the patients' age, gender or TNM stage.
CONCLUSIONOCT4 protein expression is associated with tumor differentiation and metastasis in bladder cancer and may play an important role in the early diagnosis and prognostic evaluation of bladder cancer.
Cell Line, Tumor ; Humans ; Neoplasm Metastasis ; Neoplasm Staging ; Octamer Transcription Factor-3 ; metabolism ; Prognosis ; Urinary Bladder Neoplasms ; diagnosis ; metabolism ; pathology
6.Modulation of the caveolin-3 localization to caveolae and STAT3 to mitochondria by catecholamine-induced cardiac hypertrophy in H9c2 cardiomyoblasts.
Kyuho JEONG ; Hayeong KWON ; Chanhee MIN ; Yunbae PAK
Experimental & Molecular Medicine 2009;41(4):226-235
We investigated the effect of phenylephrine (PE)- and isoproterenol (ISO)-induced cardiac hypertrophy on subcellular localization and expression of caveolin-3 and STAT3 in H9c2 cardiomyoblast cells. Caveolin-3 localization to plasma membrane was attenuated and localization of caveolin-3 to caveolae in the plasma membrane was 24.3% reduced by the catecholamine-induced hypertrophy. STAT3 and phospho-STAT3 were up-regulated but verapamil and cyclosporin A synergistically decreased the STAT3 and phospho-STAT3 levels in PE- and ISO-induced hypertrophic cells. Both expression and activation of STAT3 were increased in the nucleus by the hypertrophy. Immunofluorescence analysis revealed that the catecholamine-induced hypertrophy promoted nuclear localization of pY705-STAT3. Of interest, phosphorylation of pS727-STAT3 in mitochondria was significantly reduced by catecholamine-induced hypertrophy. In addition, mitochondrial complexes II and III were greatly down-regulated in the hypertrophic cells. Our data suggest that the alterations in nuclear and mitochondrial activation of STAT3 and caveolae localization of caveolin-3 are related to the development of the catecholamine-induced cardiac hypertrophy.
Animals
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Catecholamines/*pharmacology
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Caveolae/*metabolism
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Caveolin 3/*metabolism
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Cell Line
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Hypertrophy/metabolism
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Mitochondria/*metabolism
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Myocardium/cytology/*pathology
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Myocytes, Cardiac/cytology/*drug effects/metabolism
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Rats
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STAT3 Transcription Factor/*metabolism
8.Study of the expression of nuclear factor-kappa B, matrix metalloproteinase-3, -9 on nasopharyngeal carcinoma and their clinical significance.
Xin HU ; Jianguo TANG ; Junfen PAN ; Guomin WU
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2010;24(15):678-682
OBJECTIVE:
To test the expression of NF-kappaB/p65, MMP-3 and MMP-9 in nasopharyngeal carcinoma (NPC), and analyze their relationship and the clinical significance.
METHOD:
All samples were examined for the expression of NF-kappaB/p65, MMP-3 and MMP-9 by streptavidin-peroxidase immunohistochemistry. Chi2-test and Spearman-test were used to exam the correlation within them and the expression difference between nasopharyngeal carcinoma and normal nasopharyngeal mucosa.
RESULT:
Positive expression rate of NF-kappaB/p65 in nasopharyngeal carcinoma was 78.0%; positive expressions rate of MMP-3 and MMP-9 in nasopharyngeal carcinoma were 75.6%. There was positive relationship between NF-kappaB/p65, MMP-3, MMP-9 and N stage. The expression of NF-kappaB/p65 showed a significant positive correlation with the expression of MMP-3 and MMP-9. MMP-3 also had a significant positive correlation with MMP-9.
CONCLUSION
The result suggests that NF-kappaB/p65, MMP-3 and MMP-9 are highly expressed in nasopharyngeal carcinoma cells. Their expression is correlated with lymph nodes metastasis, but do not have relationship with sex, age, pathological classification and clinical stage. Each of them has positive correlation with the others.
Adult
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Aged
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Female
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Humans
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Male
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Matrix Metalloproteinase 3
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metabolism
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Matrix Metalloproteinase 9
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metabolism
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Middle Aged
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NF-kappa B
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metabolism
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Nasopharyngeal Neoplasms
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metabolism
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pathology
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Transcription Factor RelA
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metabolism
9.Effects of Sinopodophyllum hexundrum on apoptosis in K562 cells.
Fang-Zhu ZHOU ; Xin WANG ; An-Ya DAI ; Zheng-Lan HUANG ; Hui LI ; Ning-Shu HUANG ; Wen-Li FENG
Journal of Southern Medical University 2016;37(2):226-231
OBJECTIVETo investigate the effects of Sinopodophyllum hexundrum on apoptosis in K562 cells.
METHODSK562 cells were treated with Sinopodophyllum hexundrum at different concentrations and for different lengths of time to determine the optimal conditions of SinoPodophyllum hexandrum treatment for K562 cells using CCK8 assay. The cell apoptotic rate was detected by flow cytometry, and the cell morphology and nuclear morphology of K562 cells were observed with Wright staining and DPAI staining, respectively. The protein expressions of BCR/ABL, p-BCR/ABL, STAT5, p-STAT5 and the apoptosis-related proteins PARP, caspase-3 and cleaved-caspase-3 were determined with Western blotting.
RESULTSThe cell proliferation was inhibited in a concentration-and time-dependent manner by 1, 2, and 3 µg/mL Sinopodophyllum hexundrum. The treatment was optimal with a Sinopodophyllum hexundrum concentration of 2 µg/mL a treatment time of 48 h, and the cell apoptotic rate increased in a time-dependent manner and significantly increased at 48 h (P<0.001). The expression of apoptosis-related proteins PARP, caspase-3 and cleaved-caspase-3 were also activated in a time-dependent manner. The cells showed typical apoptotic changes after treatment with 2 µg/mL Sinopodophyllum hexundrum for 48 h with significantly reduced expressions of BCR/ABL, p-BCR/ABL, STAT5, AND p-STAT5.
CONCLUSIONSinopodophyllum hexundrum promotes K562 cell apoptosis possibly by inhibiting BCR/ABL-STAT5 survival signal pathways and activating the mitochondrion-associated apoptotic pathways.
Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cell Proliferation ; Drugs, Chinese Herbal ; pharmacology ; Fusion Proteins, bcr-abl ; metabolism ; Humans ; K562 Cells ; Mitochondria ; metabolism ; STAT5 Transcription Factor ; metabolism ; Signal Transduction
10.Constitutive stabilization of hypoxia-inducible factor alpha selectively promotes the self-renewal of mesenchymal progenitors and maintains mesenchymal stromal cells in an undifferentiated state.
In Ho PARK ; Kwang Ho KIM ; Hyun Kyung CHOI ; Jae Seung SHIM ; Soo Young WHANG ; Sang JUNE HAHN ; Oh Joo KWON ; Il Hoan OH
Experimental & Molecular Medicine 2013;45(9):e44-
With the increasing use of culture-expanded mesenchymal stromal cells (MSCs) for cell therapies, factors that regulate the cellular characteristics of MSCs have been of major interest. Oxygen concentration has been shown to influence the functions of MSCs, as well as other normal and malignant stem cells. However, the underlying mechanisms of hypoxic responses and the precise role of hypoxia-inducible factor-1alpha (Hif-1alpha), the master regulatory protein of hypoxia, in MSCs remain unclear, due to the limited span of Hif-1alpha stabilization and the complex network of hypoxic responses. In this study, to further define the significance of Hif-1alpha in MSC function during their self-renewal and terminal differentiation, we established adult bone marrow (BM)-derived MSCs that are able to sustain high level expression of ubiquitin-resistant Hif-1alpha during such long-term biological processes. Using this model, we show that the stabilization of Hif-1alpha proteins exerts a selective influence on colony-forming mesenchymal progenitors promoting their self-renewal and proliferation, without affecting the proliferation of the MSC mass population. Moreover, Hif-1alpha stabilization in MSCs led to the induction of pluripotent genes (oct-4 and klf-4) and the inhibition of their terminal differentiation into osteogenic and adipogenic lineages. These results provide insights into the previously unrecognized roles of Hif-1alpha proteins in maintaining the primitive state of primary MSCs and on the cellular heterogeneities in hypoxic responses among MSC populations.
*Cell Differentiation
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Cell Proliferation
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Humans
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Hypoxia-Inducible Factor 1, alpha Subunit/genetics/*metabolism
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Kruppel-Like Transcription Factors/genetics/metabolism
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Mesenchymal Stromal Cells/cytology/*metabolism/physiology
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Octamer Transcription Factor-3/genetics/metabolism
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Protein Stability