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1.
Mol Cell ; 81(6): 1216-1230.e9, 2021 03 18.
Article in English | MEDLINE | ID: mdl-33606996

ABSTRACT

Interferon-γ (IFN-γ)-mediated adaptive resistance is one major barrier to improving immunotherapy in solid tumors. However, the mechanisms are not completely understood. Here, we report that IFN-γ promotes nuclear translocation and phase separation of YAP after anti-PD-1 therapy in tumor cells. Hydrophobic interactions of the YAP coiled-coil domain mediate droplet initiation, and weak interactions of the intrinsically disordered region in the C terminus promote droplet formation. YAP partitions with the transcription factor TEAD4, the histone acetyltransferase EP300, and Mediator1 and forms transcriptional hubs for maximizing target gene transcriptions, independent of the canonical STAT1-IRF1 transcription program. Disruption of YAP phase separation reduced tumor growth, enhanced immune response, and sensitized tumor cells to anti-PD-1 therapy. YAP activity is negatively correlated with patient outcome. Our study indicates that YAP mediates the IFN-γ pro-tumor effect through its nuclear phase separation and suggests that YAP can be used as a predictive biomarker and target of anti-PD-1 combination therapy.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Drug Resistance, Neoplasm , Immune Checkpoint Inhibitors/pharmacology , Immunotherapy , Interferon-gamma/metabolism , Neoplasms, Experimental , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Transcription Factors/metabolism , A549 Cells , Adaptor Proteins, Signal Transducing/genetics , Animals , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , HEK293 Cells , Humans , Interferon-gamma/genetics , Mice , Mice, Knockout , Neoplasms, Experimental/genetics , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Neoplasms, Experimental/therapy , Programmed Cell Death 1 Receptor/genetics , Programmed Cell Death 1 Receptor/metabolism , Transcription Factors/genetics , YAP-Signaling Proteins
2.
Zhongguo Zhong Yao Za Zhi ; 39(5): 803-6, 2014 Mar.
Article in Zh | MEDLINE | ID: mdl-25204168

ABSTRACT

Six kinds of saponins (I, II, VII, PA, H) content of 22 samples of Paris polyphylla var. yunnanensis collected from different regions of Yunnan province were determined by HPLC, data was analyzed by SPSS 17. The results showed that the effect of altitude on saponin content was not significant, and the effect of growth area of saponins in P. polyphylla var. yunnanensis was significant, saponin content in sample from west Yunnan was significantly higher than that of samples from other regions.


Subject(s)
Drugs, Chinese Herbal/analysis , Liliaceae/chemistry , Saponins/analysis , Altitude , China , Chromatography, High Pressure Liquid
3.
J Cell Physiol ; 223(2): 369-75, 2010 May.
Article in English | MEDLINE | ID: mdl-20082301

ABSTRACT

Pentaploid H1 (ES) cells (5H1 cells) were accidentally obtained through one-cell cloning of octaploid H1 (ES) cells (8H1 cells) that were established from tetraploid H1 (ES) cells (4H1 cells) polyploidized using demecolcine. The number of chromosomes of 5H1 cells was 100, unlike the 40 of diploid H1 (ES) cells (2H1 cells), 80 of 4H1, and 160 of 8H1 cells. The durations of G(1), S, and G(2)/M phases of 5H1 cells were 3, 7, and 6 h, respectively, almost the same as those of 2H1, 4H1, and 8H1 cells. The cell volume of 5H1 cells was half of that of 8H1 cells, suggesting that 5H1 cells were created through abnormal cell divisions of 8H1 cells. The morphology of growing 5H1 cells was a spherical cluster similar to that of 2H1 cells and differing from the flagstone-like shape of 4H1 and 8H1 cells. Pentaploid solid tumors were formed from 5H1 cells after interperitoneal injection into the mouse abdomen, and they contained endodermal, mesodermal, and ectodermal cells as well as undifferentiated cells, suggesting both that the DNA content of 5H1 cells was retained during tumor formation and that the 5H1 cells were pluripotent. The DNA content of 5H1 cells was stable in long-term culturing as 2H1 cells, meaning that 5H1 and 2H1 cells shared similarities in DNA structure. The excellent stability of the DNA content of 5H1 cells was explained using a hypothesis for the DNA structure of polyploid cells because the pairing of homologous chromosomes in 5H1 cells is spatially forbidden.


Subject(s)
Cell Division/physiology , Cell Transformation, Neoplastic/drug effects , Chromosome Aberrations/drug effects , DNA/physiology , Demecolcine/pharmacology , Polyploidy , Animals , Antineoplastic Agents, Phytogenic/pharmacology , Cell Culture Techniques , Cell Differentiation/drug effects , Cell Differentiation/genetics , Cell Division/drug effects , Cell Lineage/drug effects , Cell Lineage/genetics , Cell Transformation, Neoplastic/chemically induced , Cells, Cultured , Chromosomal Instability/genetics , Gene Expression Regulation, Neoplastic/genetics , Mice , Neoplasms/genetics , Pluripotent Stem Cells/physiology , Stem Cell Transplantation/methods
4.
Front Oncol ; 10: 1404, 2020.
Article in English | MEDLINE | ID: mdl-32983970

ABSTRACT

Background: This study investigates the potential predictors of nivolumab plus chemotherapy or multitarget tyrosine kinase inhibitor (TKI) treatment response in patients with recurrent hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Methods: Patients with recurrent hepatitis B virus-related HCC who underwent nivolumab plus chemotherapy or TKI treatment between July 2017 and June 2019 at Jinling Hospital in China were retrospectively evaluated and included in this study. These patients also had both complete medical charts and follow-up data available. Overall survival (OS) and progression-free survival (PFS) were calculated from the date of nivolumab initiation. Survival data were compared using log-rank tests, and the associations of patient characteristics with survival were estimated using Cox regression models. Results: A total of 22 HCC patients were included in this cohort and constituted the basis for this analysis. Twenty progressed cases (91%) and 16 deaths (73%) were identified at a median follow-up of 8.8 months (range 1-25). The median OS from the time of nivolumab initiation was 10.7 months (95% CI, 0.8-20.6 months), with a median PFS of 5.1 months (95% CI, 3.1-7.0 months). The patients were divided into two risk groups according to a nomogram built by age, Eastern Cooperative Oncology Group (ECOG) status, hepatectomy status, and transarterial chemoembolization (TACE) use. The median PFS was 8.2 ± 2.8 months in the low-risk group compared with 1.9 ± 0.4 months in the high-risk group (p = 0.0018). The median OS was estimated as 16.8 ± 4.9 months for low-risk patients vs. 8.6 ± 3.5 months for high-risk patients (p = 0.13). Conclusion: Nivolumab combined with chemotherapy or TKI treatment is effective in patients with recurrent hepatitis B virus-related HCC. It is observed that previous TACE treatment is associated with a better PFS, and worse PFS in those patients who received hepatectomy. Prospective studies are warranted to evaluate the effects of nivolumab combined chemotherapy or TKI on recurrent hepatitis B virus-related HCC.

5.
Immunopharmacol Immunotoxicol ; 31(2): 238-45, 2009 Jun.
Article in English | MEDLINE | ID: mdl-18791913

ABSTRACT

The purpose of this study was to evaluate the beneficial effect of Hochu-ekki-to (TJ-41) combined with interferon-gamma (IFN gamma) on daily activity, immunological and neurological alternation in a mouse model of chronic fatigue syndrome (CFS). CFS was induced by 6 times of repeated injection of Brucella abortus antigen every 2 weeks. Both single TJ-41 and TJ-41 combined with IFN gamma increased running activity and thymus weight of CFS mice, while thicker thymic cortex together with elevation of natural killer cell activity was only found in the combined treatment group. No significant improvement was observed in the atrophic brain and decreased expression level of brain-derived neurotrophic factor and Bcl-2 mRNA in hippocampus in both treatment groups. Our results suggest that TJ-41 combined with IFN gamma might have a protective effect on the marked reduction in the activity in a model of CFS via normalization of host immune responses, but not neuroprotection.


Subject(s)
Drugs, Chinese Herbal/administration & dosage , Fatigue Syndrome, Chronic/drug therapy , Interferon-gamma/administration & dosage , Killer Cells, Natural/drug effects , Motor Activity/drug effects , Activities of Daily Living , Animals , Antigens, Bacterial/immunology , Brain-Derived Neurotrophic Factor/analysis , Brain-Derived Neurotrophic Factor/immunology , Brucella abortus/immunology , Fatigue Syndrome, Chronic/immunology , Fatigue Syndrome, Chronic/pathology , Female , Genes, bcl-2/drug effects , Genes, bcl-2/immunology , Hippocampus/drug effects , Hippocampus/immunology , Hippocampus/pathology , Killer Cells, Natural/immunology , Killer Cells, Natural/pathology , Mice , Mice, Inbred BALB C , Motor Activity/immunology , Neuroprotective Agents/administration & dosage , Neuroprotective Agents/immunology , Organ Size/drug effects , Organ Size/immunology , Spleen/drug effects , Spleen/immunology , Spleen/pathology , Thymus Gland/drug effects , Thymus Gland/immunology , Thymus Gland/pathology
6.
Onco Targets Ther ; 12: 5805-5811, 2019.
Article in English | MEDLINE | ID: mdl-31410025

ABSTRACT

OBJECTIVE: Although advances have been made in the clinical and therapeutic management of women with cervical cancer, the best treatment for patients with metastatic or recurrent cervical cancer is still undefined. Apatinib, a novel inhibitor of vascular endothelial growth factor receptor-2 tyrosine kinases, has been successful in treating various malignancies. This study was conducted to evaluate the efficacy and safety of apatinib in the treatment of recurrent cervical cancer. METHODS: Patients with recurrent cervical cancer received apatinib after failure of the second- or higher-line chemotherapy. Apatinib was administered as 500 mg daily on days 1 through 21 of each 4-week cycle. The primary endpoint was overall survival (OS), and the secondary endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events were reviewed and evaluated. RESULTS: Six patients were administered apatinib for at least one complete cycle. The median OS was 16.0 months (95% CI: 6.8-25.2), and the median PFS was 7.0 months (95% CI: 2.2-11.8), One patient achieved partial response and three patients achieved stable disease. Two patients were evaluated as progression disease. The ORR was 16.7% (1/6) and the DCR was 67.7% (4/6). The common side effect of apatinib was hypertension; however, the toxicity of apatinib was tolerable and controllable. CONCLUSIONS: Apatinib is an option in the treatment of recurrent cervical cancer after failure of the second- or higher-line chemotherapy. Further prospective evaluation of the utility of apatinib is required.

7.
Cancer Manag Res ; 11: 8869-8876, 2019.
Article in English | MEDLINE | ID: mdl-31632146

ABSTRACT

OBJECTIVES: Despite recent advances in the treatment of advanced ovarian cancer, drug selection after second-line chemotherapy has not been well studied. In this study, we retrospectively evaluated the effect and safety of apatinib as monotherapy or in combination with chemotherapy for the treatment of advanced ovarian cancer after second-line treatment. METHODS: We reviewed the medical records of patients from April 2016 to October 2018 with advanced ovarian cancer who received apatinib after failed second-line chemotherapy. Overall survival (OS) and progression-free survival (PFS) were calculated by the Kaplan-Meier method. Response rate (RR) and disease control rate (DCR) were evaluated using radiologic reports according to RECIST 1.1 criteria. Treatment-related adverse events were evaluated based on NCI-CTC version 4.0. RESULTS: Study concerned 22 evaluated cases; of them, 13 patients received apatinib combined with chemotherapy and 9 patients received apatinib monotherapy. The median PFS was 8.2 months (9.7 months in combined group and 4.4 months in monotherapy group, P value was 0.21). The median OS was 13.1 months (13.6 months in combined group and 11.6 months in monotherapy group, P value was 0.45). The RR was 20% and DCR was 85% (combined group: RR 33.3%, DCR 100%, monotherapy group: RR 0%, DCR 62.5%). The main side effect was hypertension (9/22), proteinuria (7/22), oral mucositis (5/22), hand and foot syndrome (6/22%), leukopenia (5/22), etc. CONCLUSION: Apatinib showed good efficacy and safety for advanced ovarian cancer patients whether used alone or in combination with chemotherapy. In the meanwhile, this study is limited by the small cases number. Therefore, further research is needed to provide more data and ultimately apply it to guide clinical practice.

8.
Hum Cell ; 21(2): 18-27, 2008 May.
Article in English | MEDLINE | ID: mdl-18397471

ABSTRACT

To examine the alteration in cellular characteristics of polyploid ES cells during long-term culturing, tetraploid H-1 (ES) cells were continuously cultured for 180 days. Cellular DNA content of the tetraploid cells decreased and reached a plateau of 3.3 C, where C represents the complement of haploid chromosomes. The chromosome number also decreased, indicating that the DNA loss was induced by chromosome loss. Cell volume was maintained, suggesting that the DNA loss did not involve cytoplasmic loss. The cell cycle parameters were almost the same during the DNA decay process, indicating that cell cycle progression was independent of the quantity of homologous chromosomes. Hypotetraploid cells showed alkaline phosphatase activity and formed teratocarcinomas in mouse abdomens, suggesting that the pluripotent potential was maintained. Cellular morphology was also retained, suggesting that the gene expression specifying morphological characteristics was conserved. We conclude that these initial cellular characteristics of tetraploid H1 (ES) cells were preserved in long-term culture, irrespective of chromosome loss.


Subject(s)
Cell Culture Techniques , Embryonic Stem Cells , Pluripotent Stem Cells , Alkaline Phosphatase/metabolism , Animals , Blastocyst/cytology , Cell Cycle/genetics , Chromosomes , DNA , Embryonic Stem Cells/cytology , Embryonic Stem Cells/enzymology , Embryonic Stem Cells/pathology , Gene Expression Regulation, Developmental , Mice , Mice, Inbred C3H , Pluripotent Stem Cells/cytology , Pluripotent Stem Cells/enzymology , Pluripotent Stem Cells/pathology , Polyploidy , Teratocarcinoma/pathology , Time Factors
9.
IBRO Rep ; 2: 81-86, 2017 Jun.
Article in English | MEDLINE | ID: mdl-30135936

ABSTRACT

By using a 5-day forced swimming test (FS) that we previously developed, swim immobility was induced in 3xTg Alzheimer's model mice and wild-type (WT) mice. After the initial 5-day FS, the next and last swimming session was performed at a 4-week interval, during which the immobility was reduced in 3xTg mice, but was maintained fully in WT mice. After FS, context-dependent fear learning was normally induced in WT mice, but was impaired in 3xTg mice, suggesting that FS may exaggerate cognitive deficits typical to 3xTg mice. Hippocampal long-term potentiation (LTP) at Schaffer collateral-CA1 synapses was suppressed by FS in WT mice, but not in 3xTg mice, indicating that FS modifies LTP in the WT mouse hippocampus, but not in 3xTg tissue. FS increased excitability of cingulate cortex pyramidal cells similarly in WT and 3xTg mice. Agreeing with our previous finding that expression of Homer1a protein is decreased in the cingulate cortex in harmony with FS-induced immobility, western blot showed that Homer1a expression is reduced by FS in the WT mice. In 3xTg mice, by contrast, FS failed to reduce Homer1a expression. The disrupted endurance of FS-induced immobility in 3xTg mice appears to be attributable to impaired cognition typical to this genotype. Failure of FS to alter LTP magnitude might be related to unaltered Homer1a expression after FS in 3xTg mice.

10.
Brain Res ; 1605: 70-5, 2015 Apr 24.
Article in English | MEDLINE | ID: mdl-25684310

ABSTRACT

Homer1a is implicated in depression in humans and depression-like behavior in mice. To further understand the role of Homer1a in stress-induced emotional changes, we applied very mild stress to Homer1a knockout (H1a KO) mice. The wild-type (WT) and H1a KO mice were restrained for 2h daily for 7 consecutive days at the same time of the day. The restraint was so mild that no changes in anxiety- or depression-like behavior were detected in either type of mice. However, total locomotion in the open field test and forced swimming test was increased by restraint in H1a KO mice only. After behavior, we made brain slices to examine neuronal excitability in cingulate cortex pyramidal cells and synaptic efficiency in hippocampal CA1 synapses. The excitability, assessed on the basis of the frequency of spikes elicited by current injection, was increased by restraint in H1a KO mice. The synaptic efficiency was evaluated by comparing the input-output relationship between the size of fiber volley and the slope of field excitatory postsynaptic potentials, and was shown to be increased by restraint in H1a KO mice only. Thus, predictable subtle stress, which failed to induce behavioral or electrophysiological changes in WT mice, resulted in a minor behavioral change that accompany upregulation of neuronal excitability and synaptic efficiency in H1a KO mice, suggesting that Homer1a may play a critical role in resilience to subtle stress.


Subject(s)
Behavior, Animal/physiology , Carrier Proteins/physiology , Stress, Physiological/physiology , Animals , Anxiety/etiology , CA1 Region, Hippocampal/physiology , Depression/etiology , Excitatory Postsynaptic Potentials/physiology , Homer Scaffolding Proteins , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Pyramidal Cells/physiology , Restraint, Physical
11.
Neuropharmacology ; 97: 210-9, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26051398

ABSTRACT

Transcranial magnetic stimulation (TMS) is fragmentarily reported to be beneficial to Alzheimer's patients. Its underlying mechanism was investigated. TMS was applied at 1, 10 or 15 Hz daily for 4 weeks to young Alzheimer's disease model mice (3xTg), in which intracellular soluble amyloid-ß is notably accumulated. Hippocampal long-term potentiation (LTP) was tested after behavior. TMS ameliorated spatial learning deficits and enhanced LTP in the same frequency-dependent manner. Activity of the large conductance calcium-activated potassium (Big-K; BK) channels was suppressed in 3xTg mice and recovered by TMS frequency-dependently. These suppression and recovery were accompanied by increase and decrease in cortical excitability, respectively. TMS frequency-dependently enhanced the expression of the activity-dependently expressed scaffold protein Homer1a, which turned out to enhance BK channel activity. Isopimaric acid, an activator of the BK channel, magnified LTP. Amyloid-ß lowering was detected after TMS in 3xTg mice. In 3xTg mice with Homer1a knocked out, amyloid-ß lowering was not detected, though the TMS effects on BK channel and LTP remained. We concluded that TMS facilitates BK channels both Homer1a-dependently and -independently, thereby enhancing hippocampal LTP and decreasing cortical excitability. Reduced excitability contributed to amyloid-ß lowering. A cascade of these correlated processes, triggered by TMS, was likely to improve learning in 3xTg mice.


Subject(s)
Alzheimer Disease/physiopathology , Alzheimer Disease/therapy , Hippocampus/physiopathology , Large-Conductance Calcium-Activated Potassium Channels/metabolism , Maze Learning/physiology , Transcranial Magnetic Stimulation , Animals , Carboxylic Acids/pharmacology , Carrier Proteins/genetics , Carrier Proteins/metabolism , Disease Models, Animal , Hippocampus/drug effects , Homer Scaffolding Proteins , Long-Term Potentiation/drug effects , Long-Term Potentiation/physiology , Male , Membrane Transport Modulators/pharmacology , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Neurons/drug effects , Neurons/physiology , Phenanthrenes/pharmacology , Tissue Culture Techniques
12.
Curr Alzheimer Res ; 12(9): 860-9, 2015.
Article in English | MEDLINE | ID: mdl-26159188

ABSTRACT

We previously reported that activity of the large conductance calcium-activated potassium (big-K, BK) channel is suppressed by intracellular Aß in cortical pyramidal cells, and that this suppression was reversed by expression of the scaffold protein Homer1a in 3xTg Alzheimer's disease model mice. Homer1a is known to be expressed by physiological photic stimulation (PS) as well. The possibility thus arises that PS also reverses Aß-induced suppression of BK channels, and thereby improves cognition in 3xTg mice. This possibility was tested here. Chronic application of 6-hour-long PS (frequency, 2 Hz; duty cycle, about 1/10; luminance, 300 lx) daily for 4 weeks improved contextual and tone-dependent fear memory in 3xTg mice and, to a lesser extent, Morris water maze performance as well. Hippocampal long-term potentiation was also enhanced after PS. BK channel activity in cingulate cortex pyramidal cells and lateral amygdalar principal cells, suppressed in 3xTg mice, were facilitated. In parallel, neuronal excitability, elevated in 3xTg mice, was recovered to the control level. Gene expression of BK channel, as well as that of the scaffold protein Homer1a, was found decreased in 3xTg mice and reversed by PS. It is known that Homer1a is an activity-dependently inducible immediate early gene product. Consistently, our previous findings showed that Homer1a induced by electrical stimulation facilitated BK channels. By using Homer1a knockouts, we showed that the present PS-induced BK channel facilitation is mediated by Homer1a expression. We thus propose that PS might be potentially useful as a non-invasive therapeutic measure against Alzheimer's disease.


Subject(s)
Alzheimer Disease/physiopathology , Alzheimer Disease/therapy , Brain/physiopathology , Maze Learning/physiology , Memory/physiology , Phototherapy/methods , Alzheimer Disease/psychology , Animals , Auditory Perception/physiology , Carrier Proteins/genetics , Carrier Proteins/metabolism , Disease Models, Animal , Fear/physiology , Gene Expression , Homer Scaffolding Proteins , Large-Conductance Calcium-Activated Potassium Channels/metabolism , Long-Term Potentiation/physiology , Male , Mice, Transgenic , Neurons/physiology , Tissue Culture Techniques , Treatment Outcome
13.
World J Gastroenterol ; 9(1): 184-7, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12508379

ABSTRACT

AIM: To explore the potential carcinogenicity of bile from congenital choledochal cyst (CCC) patients and the mechanism of the carcinogenesis in congenital choledochal cyst patients. METHODS: 20 bile samples from congenital choledochal cyst patients and 10 normal control bile samples were used for this study. The proliferative effect of bile was measured by using Methabenzthiazuron (MTT) assay; Cell cycle and apoptosis were analyzed by using flow cytometry (FCM), and the PGE(2) levels in the supernatant of cultured cholangiocarcinoma cells were quantitated by enzyme-linked immunoabsorbent assay (ELISA). RESULTS: CCC bile could significantly promote the proliferation of human cholangiocarcinoma QBC939 cells compared with normal bile (P=0.001) and negative control group (P=0.002), and the proliferative effect of CCC bile could be abolished by addition of cyclooxygenase-2 specific inhibitor celecoxib (20 microM). The QBC939 cells proliferative index was increased significantly after treated with 1 % bile from CCC patient (P=0.008) for 24 h, the percentage of S phase (29.48+/-3.27)% was increased remarkably (P<0.001) compared with normal bile (11.72+/-2.70) %, and the percentage of G0/G1 phase (54.19+/-9.46) % was decreased remarkably (P=0.042) compared with normal bile (69.16+/-10.88) %, however, bile from CCC patient had no significant influence on apoptosis of QBC939 cells (P=0.719). CONCLUSION: Bile from congenital choledochal cyst patients can promote the proliferation of human cholangiocarcinoma QBC939 cells via COX-2 and PGE(2) pathway.


Subject(s)
Bile/metabolism , Carcinogens , Cell Division , Choledochal Cyst/metabolism , Adolescent , Adult , Animals , Apoptosis , Celecoxib , Cell Cycle , Child , Child, Preschool , Cyclooxygenase 2 , Cyclooxygenase 2 Inhibitors , Cyclooxygenase Inhibitors/metabolism , Dinoprostone/metabolism , Female , Flow Cytometry , Humans , Isoenzymes/metabolism , Male , Membrane Proteins , Middle Aged , Prostaglandin-Endoperoxide Synthases/metabolism , Pyrazoles , Sulfonamides/metabolism , Tumor Cells, Cultured
14.
Hum Cell ; 24(1): 13-20, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21547691

ABSTRACT

Hexaploid H1 (ES) cells (6H1 cells) were established from octaploid H1 cells (8H1 cells), as were pentaploid H1 cells (5H1 cells). 6H1 cells were compared with 5H1 cells. The number of chromosomes of 6H1 cells was 115, 20 more than the 95 of 5H1 cells. The durations of G(1), S, and G(2)/M phases of 6H1 cells were 3, 7, and 6 h, respectively, almost the same as those of 5H1 cells. The cell volume of 6H1 cells was equivalent that of 5H1 cells. The morphology of 6H1 cells was flattened circular cluster, different from the spherical cluster of 5H1 cells. 6H1 cells exhibited alkaline phosphatase activity as well as 5H1 cells. The DNA content of 6H1 cells was stable and maintained for 300 days of culturing, the same as that of 5H1 cells. The DNA stability of 6H1 cells was explained using a hypothesis concerning the DNA structure of polyploid cells because the asymmetric configuration of homologous chromosomes in 6H1 cells inhibited chromosome loss.


Subject(s)
Chromosomes , DNA/physiology , Embryonic Stem Cells/cytology , Polyploidy , Alkaline Phosphatase/analysis , Animals , Cell Size , Cells, Cultured , Cloning, Organism , Mice
15.
Hum Cell ; 23(4): 134-40, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21166884

ABSTRACT

To examine the alteration in cellular characteristics of polyploid embryonic stem (ES) cells during long-term culturing without leukemia inhibitory factor (LIF), mouse diploid and tetraploid H-1 (ES) cells (2H1 and 4H1 cells, respectively) were cultured without LIF for approximately 5 months. 2H1 and 4H1 cells were adapted to the medium without LIF by decreasing the concentration for several passages, and they were denoted as 2H1(⁻) and 4H1(⁻) cells, respectively. DNA content of 4H1(⁻) cells decreased gradually in the early stage, increased abruptly in the second stage, and then was maintained for a long time. 4H1(⁻) cells exhibited longer doubling time and equivalent phase fraction compared with those of 2H1(⁻) cells. The G1 phase fractions of 2H1(⁻) and 4H1(⁻) cells were increased compared with that of 2H1 cells. Cellular morphology and pluripotency were maintained in 4H1(⁻) cells but not in 2H1(⁻) cells. 2H1(⁻) cells showed a cell population consisting of several kinds of cells, and they lost alkaline phosphatase activity, suggesting that the cells had differentiated. 4H1(⁻) cells, however, exhibited alkaline phosphatase activity and formed teratocarcinoma in mouse abdomen, suggesting that the cells maintained their pluripotency in the medium without LIF.


Subject(s)
Culture Media , Diploidy , Embryo, Mammalian/cytology , Embryonic Stem Cells/cytology , Tetraploidy , Alkaline Phosphatase/metabolism , Animals , Blastocyst/cytology , Cell Differentiation , Cell Division , Cell Transformation, Neoplastic , Cells, Cultured , Embryonic Stem Cells/enzymology , Embryonic Stem Cells/pathology , Leukemia Inhibitory Factor , Male , Mice , Mice, Inbred C3H , Neoplasm Transplantation , Teratocarcinoma/pathology , Time Factors
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