Background: Our previous study showed that overexpression of hepatocyte nuclear factor 4α(HNF4α) could directly promote mesenchymal stem cells(MSCs) to differentiate into hepatocyte-like cells. However, the efficien...Background: Our previous study showed that overexpression of hepatocyte nuclear factor 4α(HNF4α) could directly promote mesenchymal stem cells(MSCs) to differentiate into hepatocyte-like cells. However, the efficiency of hepatic differentiation remains low. The purpose of our study was to establish an MSC cell line that overexpressed HNF4α and FOXA2 genes to obtain an increased hepatic differentiation efficiency and hepatocyte-like cells with more mature hepatocyte functions. Methods: Successful establishment of high-level HNF4α and FOXA2 co-overexpression in human induced hepatocyte-like cells(hi Hep cells) was verified by flow cytometry, immunofluorescence and RT-PCR. Measurements of albumin(ALB), urea, glucose, indocyanine green(ICG) uptake and release, cytochrome P450(CYP) activity and gene expression were used to analyze mature hepatic functions of hi Hep cells. Results: hi Hep cells efficiently express HNF4α and FOXA2 genes and proteins, exhibit typical epithelial morphology and acquire mature hepatocyte-like cell functions, including ALB secretion, urea production, ICG uptake and release, and glycogen storage. hi Hep cells can be activated by CYP inducers. The percentage of both ALB and α-1-antitrypsin(AAT)-positive cells was approximately 72.6%. The expression levels of hepatocyte-specific genes( ALB, AAT, and CYP1A1) and liver drug transport-related genes( ABCB1, ABCG2, and SLC22A18) in hi Hep cells were significantly higher than those in MSCs-Vector cells. The hi Hep cells did not form tumors after subcutaneous xenograft in BALB/c nude mice after 2 months. Conclusion: This study provides an accessible, feasible and efficient strategy to generate hi Hep cells from MSCs.展开更多
AIM: To investigate the differentiation status and key factors to facilitate hepatic differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). METHODS: Human MSCs derived from bone marrow were induce...AIM: To investigate the differentiation status and key factors to facilitate hepatic differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). METHODS: Human MSCs derived from bone marrow were induced into hepatocyte-like cells following a previously published protocol. The differentiation status of the hepatocyte-like cells was compared with various human hepatoma cell lines. Overexpression of hepatocyte nuclear factor (HNF)-4α was mediated by adenovirus infection of these hepatocyte-like cells. The expression of interesting genes was then examined by either re-verse transcription-polymerase chain reaction (RT-PCR) or real-time RT-PCR methods. RESULTS: Our results demonstrated that the differentiation status of hepatocyte-like cells induced from human MSCs was relatively similar to poorly differentiated human hepatoma cell lines. Interestingly, the HNF-4 isoform in induced MSCs and poorly differentiated human hepatoma cell lines was identified as HNF4γ instead of HNF-4α. Overexpression of HNF-4α in induced MSCs significantly enhanced the expression level of hepatic-specific genes, liver-enriched transcription factors, and cytochrome P450 (P450) genes. CONCLUSION: Overexpression of HNF-4α improves the hepatic differentiation of human MSCs from bone marrow and is a simple way of providing better cell sources for clinical applications.展开更多
AIM To examine whether nuclear factor kappa B(NF-κB) activity regulates LIN28 B expression and their roles in leukemia stem cell(LSC)-like properties. METHODS We used pharmacological inhibitor and cell viability assa...AIM To examine whether nuclear factor kappa B(NF-κB) activity regulates LIN28 B expression and their roles in leukemia stem cell(LSC)-like properties. METHODS We used pharmacological inhibitor and cell viability assays to examine the relation between NF-κB and LIN28 B. Western blot and q RT-PCR was employed to determine their protein and m RNA levels. Luciferase reporter was constructed and applied to explore the transcriptional regulation of LIN28 B. We manipulated LIN28 B level in acute myeloid leukemia(AML) cells and investigated LSC-like properties with colony forming and serial replating assays. RESULTS This study revealed the relationship between NF-κB and LIN28 B in AML cells through drug inhibition and overexpression experiments. Notably,inhibition of NF-κB by pharmacological inhibitors reduced LIN28 B expression and decreased cell proliferation. We demonstrated that NF-κB binds to the-819 to-811 region of LIN28 B promoter,and transcriptionally regulates LIN28 B expression. LIN28 B protein was significantly elevated in NFκB1 transfected cells compared to vector control. Importantly,ectopic expression of LIN28 B partially rescued the self-renewal capacity impaired by pharmacological inhibition of NF-κB activity. CONCLUSION These results uncover a regulatory signaling,NF-κB/LIN28 B,which plays a pivotal role in leukemia stem cell-like properties and it could serve as a promising intervening target for effective treatment of AML disease.展开更多
The present study observed the dynamic expression of CD133,nuclear factor-κB and glial fibrillary acidic protein in the hippocampal CA3 area of the experimental posttraumatic epilepsy rats to investigate whether glio...The present study observed the dynamic expression of CD133,nuclear factor-κB and glial fibrillary acidic protein in the hippocampal CA3 area of the experimental posttraumatic epilepsy rats to investigate whether gliosis occurs after posttraumatic epilepsy.CD133 and nuclear factor-κB expression was increased at 1 day after posttraumatic epilepsy,peaked at 7 days,and gradually decreased up to 14 days,as seen by double-immunohistochemical staining.Glial fibrillary acidic protein/nuclear factor-κB double-labeled cells increased with time and peaked at 14 days after posttraumatic epilepsy.Results show that activation of hippocampal neural stem cells and glial proliferation after posttraumatic epilepsy-induced oxidative stress increases hippocampal glial cell density.展开更多
Bone marrow(BM) cavities are utilized for hematopoiesis and to maintain hematopoietic stem cells(HSCs). HSCs have the ability to self-renew as well as to differentiate into multiple different hematopoietic lineage cel...Bone marrow(BM) cavities are utilized for hematopoiesis and to maintain hematopoietic stem cells(HSCs). HSCs have the ability to self-renew as well as to differentiate into multiple different hematopoietic lineage cells. HSCs produce their daughter cells throughout the lifespan of individuals and thus, maintaining HSCs is crucial for individual life. BM cavities provide a specialized microenvironment termed "niche" to support HSCs. Niches are composed of various types of cells such as osteoblasts, endothelial cells and reticular cells. Osteoclasts are unique cells which resorb bones and are required for BM cavity formation. Loss of osteoclast function or differentiation results in inhibition of BM cavity formation, an osteopetrotic phenotype. Osteoclasts are also reportedly required for hematopoietic stem and progenitor cell(HSPC) mobilization to the periphery from BM cavities. Thus, lack of osteoclasts likely results in inhibition of HSC maintenance and HSPC mobilization. However, we found that osteoclasts are dispensable for hematopoietic stem cell maintenance and mobilization by using three independent osteoclast-less animal models. In this review, I will discuss the roles of osteoclasts in hematopoietic stem cell maintenance and mobilization.展开更多
基金supported by grants from the National Natu-ral Science Foundation of China(81501561)Medical Scientific Re-search Foundation of Guangdong Province(A2018121)Natural Science Foundation of Guangdong Province(2014A030310043 and 2017A030313873)
文摘Background: Our previous study showed that overexpression of hepatocyte nuclear factor 4α(HNF4α) could directly promote mesenchymal stem cells(MSCs) to differentiate into hepatocyte-like cells. However, the efficiency of hepatic differentiation remains low. The purpose of our study was to establish an MSC cell line that overexpressed HNF4α and FOXA2 genes to obtain an increased hepatic differentiation efficiency and hepatocyte-like cells with more mature hepatocyte functions. Methods: Successful establishment of high-level HNF4α and FOXA2 co-overexpression in human induced hepatocyte-like cells(hi Hep cells) was verified by flow cytometry, immunofluorescence and RT-PCR. Measurements of albumin(ALB), urea, glucose, indocyanine green(ICG) uptake and release, cytochrome P450(CYP) activity and gene expression were used to analyze mature hepatic functions of hi Hep cells. Results: hi Hep cells efficiently express HNF4α and FOXA2 genes and proteins, exhibit typical epithelial morphology and acquire mature hepatocyte-like cell functions, including ALB secretion, urea production, ICG uptake and release, and glycogen storage. hi Hep cells can be activated by CYP inducers. The percentage of both ALB and α-1-antitrypsin(AAT)-positive cells was approximately 72.6%. The expression levels of hepatocyte-specific genes( ALB, AAT, and CYP1A1) and liver drug transport-related genes( ABCB1, ABCG2, and SLC22A18) in hi Hep cells were significantly higher than those in MSCs-Vector cells. The hi Hep cells did not form tumors after subcutaneous xenograft in BALB/c nude mice after 2 months. Conclusion: This study provides an accessible, feasible and efficient strategy to generate hi Hep cells from MSCs.
基金Supported by Grant MG-098-PP-08 from the National Health Research Institutes, Taiwan
文摘AIM: To investigate the differentiation status and key factors to facilitate hepatic differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). METHODS: Human MSCs derived from bone marrow were induced into hepatocyte-like cells following a previously published protocol. The differentiation status of the hepatocyte-like cells was compared with various human hepatoma cell lines. Overexpression of hepatocyte nuclear factor (HNF)-4α was mediated by adenovirus infection of these hepatocyte-like cells. The expression of interesting genes was then examined by either re-verse transcription-polymerase chain reaction (RT-PCR) or real-time RT-PCR methods. RESULTS: Our results demonstrated that the differentiation status of hepatocyte-like cells induced from human MSCs was relatively similar to poorly differentiated human hepatoma cell lines. Interestingly, the HNF-4 isoform in induced MSCs and poorly differentiated human hepatoma cell lines was identified as HNF4γ instead of HNF-4α. Overexpression of HNF-4α in induced MSCs significantly enhanced the expression level of hepatic-specific genes, liver-enriched transcription factors, and cytochrome P450 (P450) genes. CONCLUSION: Overexpression of HNF-4α improves the hepatic differentiation of human MSCs from bone marrow and is a simple way of providing better cell sources for clinical applications.
基金Supported by the Singapore National Research Foundation and the Ministry of Education under the Research Center of Excellence Program to WJ Chng and NMRC Clinician-Scientist IRG Grant CNIG11nov38(Zhou J)supported by NMRC Clinician Scientist Investigator awardpartially supported by the RNA Biology Center at CSI Singapore,NUS,from funding by the Singapore Ministry of Education’s Tier 3 Grants,No.MOE2014-T3-1-006
文摘AIM To examine whether nuclear factor kappa B(NF-κB) activity regulates LIN28 B expression and their roles in leukemia stem cell(LSC)-like properties. METHODS We used pharmacological inhibitor and cell viability assays to examine the relation between NF-κB and LIN28 B. Western blot and q RT-PCR was employed to determine their protein and m RNA levels. Luciferase reporter was constructed and applied to explore the transcriptional regulation of LIN28 B. We manipulated LIN28 B level in acute myeloid leukemia(AML) cells and investigated LSC-like properties with colony forming and serial replating assays. RESULTS This study revealed the relationship between NF-κB and LIN28 B in AML cells through drug inhibition and overexpression experiments. Notably,inhibition of NF-κB by pharmacological inhibitors reduced LIN28 B expression and decreased cell proliferation. We demonstrated that NF-κB binds to the-819 to-811 region of LIN28 B promoter,and transcriptionally regulates LIN28 B expression. LIN28 B protein was significantly elevated in NFκB1 transfected cells compared to vector control. Importantly,ectopic expression of LIN28 B partially rescued the self-renewal capacity impaired by pharmacological inhibition of NF-κB activity. CONCLUSION These results uncover a regulatory signaling,NF-κB/LIN28 B,which plays a pivotal role in leukemia stem cell-like properties and it could serve as a promising intervening target for effective treatment of AML disease.
基金the Science and Technology Foundation of Fujian Province, No. 2007F5045the Program for New Century Excellent Talents in Fujian Province University, No. NCETFJ-0702
文摘The present study observed the dynamic expression of CD133,nuclear factor-κB and glial fibrillary acidic protein in the hippocampal CA3 area of the experimental posttraumatic epilepsy rats to investigate whether gliosis occurs after posttraumatic epilepsy.CD133 and nuclear factor-κB expression was increased at 1 day after posttraumatic epilepsy,peaked at 7 days,and gradually decreased up to 14 days,as seen by double-immunohistochemical staining.Glial fibrillary acidic protein/nuclear factor-κB double-labeled cells increased with time and peaked at 14 days after posttraumatic epilepsy.Results show that activation of hippocampal neural stem cells and glial proliferation after posttraumatic epilepsy-induced oxidative stress increases hippocampal glial cell density.
文摘Bone marrow(BM) cavities are utilized for hematopoiesis and to maintain hematopoietic stem cells(HSCs). HSCs have the ability to self-renew as well as to differentiate into multiple different hematopoietic lineage cells. HSCs produce their daughter cells throughout the lifespan of individuals and thus, maintaining HSCs is crucial for individual life. BM cavities provide a specialized microenvironment termed "niche" to support HSCs. Niches are composed of various types of cells such as osteoblasts, endothelial cells and reticular cells. Osteoclasts are unique cells which resorb bones and are required for BM cavity formation. Loss of osteoclast function or differentiation results in inhibition of BM cavity formation, an osteopetrotic phenotype. Osteoclasts are also reportedly required for hematopoietic stem and progenitor cell(HSPC) mobilization to the periphery from BM cavities. Thus, lack of osteoclasts likely results in inhibition of HSC maintenance and HSPC mobilization. However, we found that osteoclasts are dispensable for hematopoietic stem cell maintenance and mobilization by using three independent osteoclast-less animal models. In this review, I will discuss the roles of osteoclasts in hematopoietic stem cell maintenance and mobilization.
