The stem/progenitor cell has long been regarded as a central cell type in development, homeostasis, and regeneration, largely owing to its robust self-renewal and multilineage differentiation abilities. The balance between self-renewal and stem/progenitor cell differentiation requires the coordinated regulation of cell cycle progression and cell fate determination. Extensive studies have demonstrated that cell cycle states determine cell fates, because cells in different cell cycle states are characterized by distinct molecular features and functional outputs. Recent advances in high-resolution epigenome profiling, single-cell transcriptomics, and cell cycle reporter systems have provided novel insights into the cell cycle regulation of cell fate determination. Here, we review recent advances in cell cycle-dependent cell fate determination and functional heterogeneity, and the application of cell cycle manipulation for cell fate conversion. These findings will provide insight into our understanding of cell cycle regulation of cell fate determination in this field, and may facilitate its potential application in translational medicine.
Animals ; Cell Cycle ; Cell Physiological Phenomena ; Epigenomics ; G1 Phase ; G2 Phase ; Humans ; Translational Medical Research

PURPOSE: Jab1 is a coactivator of c-Jun that enhances the transcriptional function of c-Jun. Jab1 is frequently overexpressed in various cancers and is associatedwith poor prognosis of cancer patients. Thus, Jab1 could be a potential therapeutic target in cancer. However, the role of Jab1 in biliary tract cancer (BTC) has not been studied. MATERIALS AND METHODS: We performed in vitro and in vivo experiments to evaluate the therapeutic potential ofJab1 inhibition in BTC. RESULTS: Among 8 BTC cell lines, many showed higher Jab1 expression levels. In addition, Jab1 silencing by siRNA increased p27 expression levels. SNU478 and HuCCT-1 cells exhibited profound Jab1 knockdown and increased p27 expression by Jab1-specific siRNA transfection. Jab1 silencing induced anti-proliferative and anti-migratory effects and resulted in G1 cell cycle arrest in SNU478 and HuCCT-1 cells. In addition, Jab1 silencing potentiated the anti-proliferative and anti-migratory effects of cisplatin by increasing DNA damage. Interestingly,Jab1 knockdown increased PTEN protein half-life, resulting in increased PTEN expression. In the HuCCT-1 mouse xenograft model, stable knockdown of Jab1 by shRNA also showed anti-proliferative effects in vivo, with decreased Ki-67 expression and AKT phosphorylation and increased Terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling and p27 expression. CONCLUSION: Jab1 knockdown demonstrated anti-proliferative and anti-migratory effects in BTC cells by increasing DNA damage and stabilizing PTEN, resulting in G1 cell cycle arrest. In addition, Jab1 silencing potentiated the anti-proliferative effects of cisplatin. Our data suggest that Jab1 may be a potential therapeutic target in BTC that is worthy of further investigations.
Animals ; Biliary Tract Neoplasms ; Biliary Tract ; Cell Line ; Cisplatin ; DNA Damage ; G1 Phase Cell Cycle Checkpoints ; Half-Life ; Heterografts ; Humans ; In Vitro Techniques ; Mice ; Phosphorylation ; Prognosis ; PTEN Phosphohydrolase ; RNA, Small Interfering ; Transfection

Reactive oxygen species (ROS) are widely generated in biological processes such as normal metabolism and response to xenobiotic exposure. While ROS can be beneficial or harmful to cells and tissues, generation of ROS by diverse anti-cancer drugs or phytochemicals plays an important role in the induction of apoptosis. We recently identified a derivative of naphthalene, MS-5, that induces apoptosis of an ovarian cell, CAOV-3. Interestingly, MS-5 induced apoptosis by down-regulating the ROS. Cell viability was evaluated by water-soluble tetrazolium salt (WST-1) assay. Apoptosis was evaluated by flow cytometry analysis. Intracellular ROS (H₂O₂), mitochondrial superoxide, mitochondrial membrane potential (MMP) and effect on cycle were determined by flow cytometry. Protein expression was assessed by western blotting. The level of ATP was measured using ATP Colorimetric/Fluorometric Assay kit. MS-5 inhibited growth of ovarian cancer cell lines, CAOV-3, in a concentration- and time-dependent manner. MS-5 also induced G1 cell cycle arrest in CAOV-3 cells, while MS-5 decreased intracellular ROS generation. In addition, cells treated with MS-5 showed the decrease in MMP and ATP production. In this study, we found that treatment with MS-5 in CAOV-3 cells induced apoptosis but decreased ROS level. We suspect that MS-5 might interfere with the minimum requirements of ROS for survival. These perturbations appear to be concentration-dependent, suggesting that MS-5 may induce apoptosis by interfering with ROS generation. We propose that MS-5 may be a potent therapeutic agent for inducing apoptosis in ovarian cancer cell through regulation of ROS.
Adenosine Triphosphate ; Apoptosis* ; Biological Processes ; Blotting, Western ; Cell Line ; Cell Survival ; Flow Cytometry ; G1 Phase Cell Cycle Checkpoints ; Membrane Potential, Mitochondrial ; Metabolism ; Ovarian Neoplasms* ; Phytochemicals ; Reactive Oxygen Species* ; Superoxides

Suppressor of Variegation 3–9 Homolog 2 (SUV39H2) methylates the lysine 9 residue of histone H3 and induces heterochromatin formation, resulting in transcriptional repression or silencing of target genes. SUV39H1 and SUV39H2 have a role in embryonic development, and SUV39H1 was shown to suppress cell cycle progression associated with Rb. However, the function of human SUV39H2 has not been extensively studied. We observed that forced expression of SUV39H2 decreased cell proliferation by inducing G1 cell cycle arrest. In addition, SUV39H2 was degraded through the ubiquitin-proteasomal pathway. Using yeast two-hybrid screening to address the degradation mechanism and function of SUV39H2, we identified translationally controlled tumor protein (TCTP) as an SUV39H2-interacting molecule. Mapping of the interacting regions indicated that the N-terminal 60 amino acids (aa) of full-length SUV39H2 and the C-terminus of TCTP (120–172 aa) were critical for binding. The interaction of SUV39H2 and TCTP was further confirmed by co-immunoprecipitation and immunofluorescence staining for colocalization. Moreover, depletion of TCTP by RNAi led to up-regulation of SUV39H2 protein, while TCTP overexpression reduced SUV39H2 protein level. The half-life of SUV39H2 protein was significantly extended upon TCTP depletion. These results clearly indicate that TCTP negatively regulates the expression of SUV39H2 post-translationally. Furthermore, SUV39H2 induced apoptotic cell death in TCTP-knockdown cells. Taken together, we identified SUV39H2, as a novel target protein of TCTP and demonstrated that SUV39H2 regulates cell proliferation of lung cancer cells.
Amino Acids ; Apoptosis ; Carrier Proteins ; Cell Cycle ; Cell Death ; Cell Proliferation ; Embryonic Development ; Female ; Fluorescent Antibody Technique ; G1 Phase Cell Cycle Checkpoints ; Half-Life ; Heterochromatin ; Histones ; Humans ; Immunoprecipitation ; Lung Neoplasms ; Lysine ; Mass Screening ; Pregnancy ; Repression, Psychology ; RNA Interference ; Up-Regulation ; Yeasts

BACKGROUND: Prostate cancer (PCa) is one of the most important causes of death in men and thus new therapeutic approaches are needed. In this study, antiproliferative and anti-migration properties of a coumarin derivative esculetin were evaluated. METHODS: Human PCa cell lines PC3, DU145, and LNCaP were treated with various concentrations of esculetin for 24 to 72 hours, and cell viability was determined by the MTT test. Cell cycle and apoptosis were analyzed by using cell-based cytometer. Gene expression levels were assessed by reverse transcription and quantitative real-time PCR, cell migration was determined by the wound healing assay. The protein expression was measured by Western blotting. RESULTS: Esculetin inhibited cell proliferation in a dose- and time-dependent manner. Cell migration was inhibited by esculetin treatment. Administration of esculetin significantly reduced the cells survival, induced apoptosis and caused the G1 phase cell cycle arrest shown by image-based cytometer. The induced expression of cytochrome c, p53, p21 and p27, and down-regulated CDK2 and CDK4 may be the underlying molecular mechanisms of esculetin effect. Esculetin suppressed phosphorylation of Akt and enhanced protein expression of tumor-suppressor phosphatase and tensin homologue. CONCLUSIONS: Our findings showed that the coumarin derivative esculetin could be used in the management of PCa. However, further in vivo research is needed.
Apoptosis ; Blotting, Western ; Cause of Death ; Cell Cycle Checkpoints ; Cell Cycle ; Cell Line ; Cell Movement ; Cell Proliferation ; Cell Survival ; Cytochromes c ; G1 Phase ; Gene Expression ; Humans ; Male ; Passive Cutaneous Anaphylaxis ; Phosphorylation ; Prostate ; Prostatic Neoplasms ; Real-Time Polymerase Chain Reaction ; Reverse Transcription ; Wound Healing

A type of breast cancer with a defect in three molecular markers such as the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor is called triple-negative breast cancer (TNBC). Many patients with TNBC have a lower survival rate than patients with other types due to a poor prognosis. In this study, we confirmed the anti-cancer effect of a natural compound, Gomisin G, in TNBC cancer cells. Treatment with Gomisin G suppressed the viability of two TNBC cell lines, MDA-MB-231 and MDA-MB-468 but not non-TNBC cell lines such as MCF-7, T47D, and ZR75-1. To investigate the molecular mechanism of this activity, we examined the signal transduction pathways after treatment with Gomisin G in MDA-MB-231 cells. Gomisin G did not induce apoptosis but drastically inhibited AKT phosphorylation and reduced the amount of retinoblastoma tumor suppressor protein (Rb) and phosphorylated Rb. Gomisin G induced in a proteasome-dependent manner a decrease in Cyclin D1. Consequently, Gomisin G causes cell cycle arrest in the G1 phase. In contrast, there was no significant change in T47D cells except for a mild decrease in AKT phosphorylation. These results show that Gomisin G has an anti-cancer activity by suppressing proliferation rather than inducing apoptosis in TNBC cells. Our study suggests that Gomisin G could be used as a therapeutic agent in the treatment of TNBC patients.
Apoptosis ; Breast Neoplasms ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Line ; Cell Proliferation ; Cyclin D1* ; Cyclins* ; Estrogens ; G1 Phase ; Humans ; Phosphorylation* ; Prognosis ; Receptor, Epidermal Growth Factor ; Receptors, Progesterone ; Retinoblastoma ; Signal Transduction ; Survival Rate ; Triple Negative Breast Neoplasms*

Cell cycle dysfunction can cause severe diseases, including neurodegenerative disease and cancer. Mutations in cyclin-dependent kinase inhibitors controlling the G1 phase of the cell cycle are prevalent in various cancers. Mice lacking the tumor suppressors p16(Ink4a) (Cdkn2a, cyclin-dependent kinase inhibitor 2a), p19(Arf) (an alternative reading frame product of Cdkn2a,), and p27(Kip1) (Cdkn1b, cyclin-dependent kinase inhibitor 1b) result in malignant progression of epithelial cancers, sarcomas, and melanomas, respectively. Here, we generated knockout mouse models for each of these three cyclin-dependent kinase inhibitors using engineered nucleases. The p16(Ink4a) and p19(Arf) knockout mice were generated via transcription activator-like effector nucleases (TALENs), and p27(Kip1) knockout mice via clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9 (CRISPR/Cas9). These gene editing technologies were targeted to the first exon of each gene, to induce frameshifts producing premature termination codons. Unlike preexisting embryonic stem cell-based knockout mice, our mouse models are free from selectable markers or other external gene insertions, permitting more precise study of cell cycle-related diseases without confounding influences of foreign DNA.
Animals ; Cell Cycle ; Codon, Nonsense ; Cyclin-Dependent Kinase Inhibitor p16 ; DNA ; Exons ; G1 Phase ; Genome* ; Melanoma ; Mice ; Mice, Knockout* ; Mutagenesis, Insertional ; Neurodegenerative Diseases ; Phosphotransferases* ; Reading Frames ; Sarcoma

Liver cancer occurs very frequently worldwide and hepatocellular carcinoma (HCC) accounts for more than 80% of total primary liver cancer cases. In this study, the anticarcinogenic effects of resveratrol against hepatitis B virus (HBV)-induced HCC were investigated by using HBV X-protein-overexpressing Huh7 (Huh7-HBx) human hepatoma cells. MTT assay showed that resveratrol decreased cell viability. Fluorescence-activated cell-sorter analysis showed that resveratrol induced G1 cell cycle arrest without increasing the sub-G1 phase cell population. Therefore, we evaluated its effect on regulation of cyclin D1, which is critically involved in G1/S transition. Resveratrol lowered cyclin D1 transcription. Western blot analysis of the effects of resveratrol on upstream cyclin D1 transcriptional signaling, extracellular signal-related kinase (ERK), p90(RSK), Akt, and p70(S6K) revealed inhibition of Akt but not the ERK signaling pathway. Collectively, the results indicate that resveratrol inhibits Huh7-HBx proliferation by decreasing cyclin D1 expression through blockade of Akt signaling. We investigated the anticarcinogenic effect and mechanism of resveratrol in xenograft model mice implanted with Huh7-HBx cells. Intraperitoneal resveratrol injection reduced tumor size in the mice. Expression of survivin was reduced, but cyclin D1 was not affected. The results demonstrate that resveratrol treatment may help manage HBV-induced HCC by regulating survivin.
Animals ; Anticarcinogenic Agents ; Blotting, Western ; Carcinoma, Hepatocellular* ; Cell Survival ; Cyclin D1 ; G1 Phase Cell Cycle Checkpoints ; Hepatitis B virus* ; Hepatitis B* ; Hepatitis* ; Heterografts ; Humans ; Liver Neoplasms ; Mice ; Phosphotransferases ; Ribosomal Protein S6 Kinases, 90-kDa

Plant-derived triterpenoids commonly possesses biological properties such as anti-inflammatory, anti-microbial, anti-viral and anti-cancer. Luvunga scandens is one of the plant that produced triterpenoids. The aims of the study was to analyze cell cycle profile and to determine the expression of p53 unregulated modulator of apoptosis (PUMA), caspase-8 and caspase-9 genes at mRNA level in MCF-7 cell line treated with two triterpenoids, flindissol (1) and 3-oxotirucalla-7,24-dien-21-oic-acid (2) isolated from L. scandens. The compounds were tested for cell cycle analysis using flow cytometer and mRNA expression level using quantitative RT-PCR. The number of MCF-7 cells population which distributed in Sub G1 phase after treated with compound 1 and 2 were 7.7 and 9.3% respectively. The evaluation of the expression of genes showed that both compounds exhibited high level of expression of PUMA, caspase-8 and caspase-9 as normalized to β-actin via activation of those genes. In summary, the isolated compounds of L. scandens plant showed promising anticancer properties in MCF-7 cell lines.
Apoptosis ; Caspase 8 ; Caspase 9 ; Cell Cycle Checkpoints* ; Cell Cycle* ; Flow Cytometry ; G1 Phase ; Gene Expression* ; MCF-7 Cells* ; Plants ; Puma ; RNA, Messenger

BACKGROUND: Stress is a known cause of hair loss in many species. OBJECTIVE: In this study, we investigated the role of acute stress on hair growth using a rat model. METHODS: Rats were immobilized for 24 hours and blood samples, and skin biopsies were taken. The effect of stress-serum on the in vitro proliferation of rat and human dermal papilla cells (hDPCs), as well as serum cortisol and corticotropin-releasing hormone levels, were measured. Mast cell staining was performed on the biopsied tissue. In addition, Western blot and quantitative real time polymerase chain reaction were used to assess mast cell tryptase and cytokine expression, respectively in rat skin biopsies. RESULTS: Stress-serum treatment reduced significantly the number of viable hDPCs and arrested the cell cycle in the G1 phase, compared to serum from unrestrained rats (p<0.05, respectively). Moreover, restrained rats had significantly higher levels of cortisol in serum than unrestrained rats (p<0.01). Acute stress serum increased mast cell numbers and mast cell tryptase expression, as well as inducing interleukin (IL)-6 and IL-1β up-regulation. CONCLUSION: These results suggest that acute stress also has an inhibitory effect on hair growth via cortisol release in addition to substance P-mast cell pathway.
Animals ; Biopsy ; Blotting, Western ; Cell Cycle ; Corticotropin-Releasing Hormone ; G1 Phase ; Hair* ; Humans ; Hydrocortisone ; In Vitro Techniques ; Interleukins ; Mast Cells* ; Models, Animal ; Rats ; Real-Time Polymerase Chain Reaction ; Skin ; Tryptases ; Up-Regulation