This paper aimed to investigate the role and potential mechanism of p53 on primordial follicle activation. Firstly, the p53 mRNA expression in the ovary of neonatal mice at 3, 5, 7 and 9 days post-partum (dpp) and the subcellular localization of p53 were detected to confirm the expression pattern of p53. Secondly, 2 dpp and 3 dpp ovaries were cultured with p53 inhibitor Pifithrin-μ (PFT-μ, 5 μmol/L) or equal volume of dimethyl sulfoxide for 3 days. The function of p53 in primordial follicle activation was determined by hematoxylin staining and whole ovary follicle counting. The proliferation of cell was detected by immunohistochemistry. The relative mRNA levels and protein levels of the key molecules involved in the classical pathways associated with the growing follicles were examined by immunofluorescence staining, Western blot and real-time PCR, respectively. Finally, rapamycin (RAP) was used to intervene the mTOR signaling pathway, and ovaries were divided into four groups: Control, RAP (1 μmol/L), PFT-μ (5 μmol/L), PFT-μ (5 μmol/L) + RAP (1 μmol/L) groups. The number of follicles in each group was determined by hematoxylin staining and whole ovary follicle counting. The results showed that the expression of p53 mRNA was decreased with the activation of primordial follicles in physiological condition. p53 was expressed in granulosa cells and oocyte cytoplasm of the primordial follicles and growing follicles, and the expression of p53 in the primordial follicles was higher than that in the growing follicles. Inhibition of p53 promoted follicle activation and reduced the primordial follicle reserve. Inhibition of p53 promoted the proliferation of the granulosa cells and oocytes. The mRNA and protein expression levels of key molecules in the PI3K/AKT signaling pathway including AKT, PTEN, and FOXO3a were not significantly changed after PFT-μ treatment, while the expression of RPS6/p-RPS6, the downstream effectors of the mTOR signaling pathway, was upregulated. Inhibition of both p53 and mTOR blocked p53 inhibition-induced primordial follicle activation. Collectively, these findings suggest that p53 may inhibit primordial follicle activation through the mTOR signaling pathway to maintain the primordial follicle reserve.
Female ; Animals ; Mice ; Tumor Suppressor Protein p53/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Hematoxylin ; Signal Transduction/physiology* ; TOR Serine-Threonine Kinases ; Sirolimus ; RNA, Messenger

Lung squamous cell carcinoma (LSCC) accounts for approximately 30% of non-small cell lung cancer (NSCLC) cases and is the second most common histological type of lung cancer. Anaplastic lymphoma kinase (ALK)-positive NSCLC accounts for only 2%-5% of all NSCLC cases, and is almost exclusively detected in patients with lung adenocarcinoma. Thus, ALK testing is not routinely performed in the LSCC population, and the efficacy of such treatment for ALK-rearranged LSCC remains unknown. Echinoderm microtubule associated protein like 4 (EML4)-ALK (V1) and TP53 co-mutations were identified by next generation sequencing (NGS) in this patient with advanced LSCC. On December 3, 2020, Ensatinib was taken orally and the efficacy was evaluated as partial response (PR). The progression-free survival (PFS) was 19 months. When the disease progressed, the medication was changed to Loratinib. To our knowledge, Enshatinib created the longest PFS of ALK-mutant LSCC patients treated with targeted therapy since literature review. Herein, we described one case treated by Enshatinib involving a patient with both EML4-ALK and TP53 positive LSCC, and the relevant literatures were reviewed for discussing the treatment of this rare disease.
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Humans ; Carcinoma, Non-Small-Cell Lung/drug therapy* ; Lung Neoplasms/pathology* ; Anaplastic Lymphoma Kinase/metabolism* ; Carcinoma, Squamous Cell/genetics* ; Mutation ; Cytoskeletal Proteins/genetics* ; Lung/pathology* ; Oncogene Proteins, Fusion/genetics* ; Protein Kinase Inhibitors/therapeutic use* ; Tumor Suppressor Protein p53/genetics*

Aging is an independent risk factor for chronic diseases in the elderly, and understanding aging mechanisms is one of the keys to achieve early prevention and effective intervention for the diseases. Aging process is dynamic and systemic, making it difficult for mechanistic study. With recent advances in aging biomarkers and development of live-imaging technologies, more and more reporter mouse models have been generated, which can live monitor the aging process, and help investigate aging mechanisms at systemic level and develop intervention strategies. This review summarizes recent advances in live-imaging aging reporter mouse models based on widely used aging biomarkers (p16^Ink4a, p21^Waf1/Cip1, p53 and Glb1), and discusses their applications in aging research.
Humans ; Animals ; Mice ; Aged ; Aging ; Cyclin-Dependent Kinase Inhibitor p16/metabolism* ; Cyclin-Dependent Kinase Inhibitor p21/metabolism* ; Biomarkers ; Tumor Suppressor Protein p53

Previous studies have shown that long-term spermatogonial stem cells (SSCs) have the potential to spontaneously transform into pluripotent stem cells, which is speculated to be related to the tumorigenesis of testicular germ cells, especially when p53 is deficient in SSCs which shows a significant increase in the spontaneous transformation efficiency. Energy metabolism has been proved to be strongly associated with the maintenance and acquisition of pluripotency. Recently, we compared the difference in chromatin accessibility and gene expression profiles between wild-type (p53^+/+) and p53 deficient (p53^-/-) mouse SSCs using the Assay for Targeting Accessible-Chromatin with high-throughput sequencing (ATAC-seq) and transcriptome sequencing (RNA-seq) techniques, and revealed that SMAD3 is a key transcription factor in the transformation of SSCs into pluripotent cells. In addition, we also observed significant changes in the expression levels of many genes related to energy metabolism after p53 deletion. To further reveal the role of p53 in the regulation of pluripotency and energy metabolism, this paper explored the effects and mechanism of p53 deletion on energy metabolism during the pluripotent transformation of SSCs. The results of ATAC-seq and RNA-seq from p53^+/+ and p53^-/- SSCs revealed that gene chromatin accessibility related to positive regulation of glycolysis and electron transfer and ATP synthesis was increased, and the transcription levels of genes encoding key glycolytic enzymes and regulating electron transport-related enzymes were markedly increased. Furthermore, transcription factors SMAD3 and SMAD4 promoted glycolysis and energy homeostasis by binding to the chromatin of the Prkag2 gene which encodes the AMPK subunit. These results suggest that p53 deficiency activates the key enzyme genes of glycolysis in SSCs and enhances the chromatin accessibility of genes associated with glycolysis activation to improve glycolysis activity and promote transformation to pluripotency. Moreover, SMAD3/SMAD4-mediated transcription of the Prkag2 gene ensures the energy demand of cells in the process of pluripotency transformation and maintains cell energy homeostasis by promoting AMPK activity. These results shed light on the importance of the crosstalk between energy metabolism and stem cell pluripotency transformation, which might be helpful for clinical research of gonadal tumors.
Animals ; Mice ; AMP-Activated Protein Kinases ; Chromatin ; Energy Metabolism ; Gene Deletion ; Stem Cells ; Tumor Suppressor Protein p53/genetics* ; Spermatogonia/cytology* ; Male

Objective To investigate the expression level of serine/threonine phosphoprotein phosphatase 4C(PPP4C)in gastric cancer,and analyze its relationship with prognosis and the underlying regulatory mechanism.Methods The clinical data of 104 gastric cancer patients admitted to the First Affiliated Hospital of Bengbu Medical College between January 2012 and August 2016 were collected.Immunohistochemical staining was employed to determine the expression levels of PPP4C and Ki-67 in the gastric cancer tissue.The gastric cancer cell lines BGC823 and HGC27 were cultured and transfected with the vector for PPP4C knockdown,the vector for PPP4C overexpression,and the lentiviral vector(control),respectively.The effects of PPP4C on the cell cycle and proliferation were analyzed and the possible regulatory mechanisms were explored.Results PPP4C was highly expressed in gastric cancer(P<0.001),and its expression promoted malignant progression of the tumor(all P<0.01).Univariate and Cox multivariate analysis clarified that high expression of PPP4C was an independent risk factor affecting the 5-year survival rate of gastric cancer patients(P=0.003).Gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis suggested that PPP4C may be involved in the cell cycle.The correlation analysis showed that the expression of PPP4C was positively correlated with that of Ki-67 in gastric cancer(P<0.001).The up-regulation of PPP4C expression increased the proportion of tumor cells in the S phase,alleviated the G2/M phase arrest,and promoted the proliferation of gastric cancer cells and the expression of cyclin D1 and cyclin-dependent kinase 6(CDK6)(all P<0.05).The down-regulation of PPP4C decreased the proportion of gastric cancer cells in the S phase,promoted G2/M phase arrest,and inhibited cell proliferation and the expression of cyclin D1,CDK6,and p53(all P<0.05).p53 inhibitors promoted the proliferation of BGC823 and HGC27 cells in the PPP4C knockdown group(P<0.001,P<0.001),while p53 activators inhibited the proliferation of BGC823 and HGC27 cells in the PPP4C overexpression group(P<0.001,P=0.002).Conclusions PPP4C is highly expressed in gastric cancer and affects the prognosis of the patients.It may increase the proportion of gastric cancer cells in the S phase and alleviate the G2/M phase arrest by inhibiting p53 signaling,thereby promoting cell proliferation.
Humans ; Stomach Neoplasms/genetics* ; Cyclin D1/metabolism* ; Tumor Suppressor Protein p53 ; Phosphoproteins/metabolism* ; Ki-67 Antigen ; Cell Line, Tumor ; Prognosis ; Cell Proliferation ; Phosphoprotein Phosphatases/metabolism* ; Threonine ; Serine

OBJECTIVE: To investigate the involvement of endothelial cells (ECs)-derived exosomes in the anti-apoptotic effect of Danhong Injection (DHI) and the mechanism of DHI-induced exosomal protection against postinfarction myocardial apoptosis. METHODS: A mouse permanent myocardial infarction (MI) model was established, followed by a 14-day daily treatment with DHI, DHI plus GW4869 (an exosomal inhibitor), or saline. Phosphate-buffered saline (PBS)-induced ECs-derived exosomes were isolated, analyzed by miRNA microarray and validated by droplet digital polymerase chain reaction (ddPCR). The exosomes induced by DHI (DHI-exo), PBS (PBS-exo), or DHI+GW4869 (GW-exo) were isolated and injected into the peri-infarct zone following MI. The protective effects of DHI and DHI-exo on MI hearts were measured by echocardiography, Masson's trichrome staining, and TUNEL apoptosis assay. The Western blotting and quantitative reverse transcription PCR (qRT-PCR) were used to evaluate the expression levels of miR-125b/p53-mediated pathway components, including miR-125b, p53, Bak, Bax, and caspase-3 activities. RESULTS: DHI significantly improved cardiac function and reduced infarct size in MI mice (P<0.01), which was abolished by the GW4869 intervention. DHI promoted the exosomal secretion in ECs (P<0.01). According to the results of exosomal miRNA microarray assay, 30 differentially expressed miRNAs in the DHI-exo were identified (28 up-regulated miRNAs and 2 down-regulated miRNAs). Among them, DHI significantly elevated miR-125b level in DHI-exo and DHI-treated ECs, a recognized apoptotic inhibitor impeding p53 signaling (P<0.05). Remarkably, treatment with DHI and DHI-exo attenuated apoptosis, elevated miR-125b expression level, inhibited capsase-3 activity, and down-regulated the expression levels of proapoptotic effectors (p53, Bak, and Bax) in post-MI hearts, whereas these effects were blocked by GW4869 (P<0.05 or P<0.01). CONCLUSION DHI and DHI-induced exosomes inhibited apoptosis, promoted the miR-125b expression level, and regulated the p53 apoptotic pathway in post-infarction myocardium.
Mice ; Animals ; Tumor Suppressor Protein p53/metabolism* ; Endothelial Cells/metabolism* ; Exosomes/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Myocardium/metabolism* ; Myocardial Infarction/drug therapy* ; Apoptosis ; MicroRNAs/metabolism*

Lnc-HUR1 is an HBV-related long non-coding RNA, which can promote the proliferation of hepatoma cells and the occurrence and development of liver cancer. In this study we explored the effect of lnc-HUR1 on the apoptosis of hepatocellular carcinoma cells by taking the approach of immunoblotting, quantitative real time PCR, luciferase reporter assay, chromatin immunoprecipitation (ChIP) and flow cytometry. We found that overexpression of lnc-HUR1 significantly reduced the activity of caspase3/7 and the cleavage of PARP-1, while knocking down of lnc-HUR1 significantly increased the activity of caspase3/7 and promoted the cleavage of PARP-1 in HepG2 cells treated with TGF-β, pentafluorouracil or staurosporine. Consistently, the data from Annexin-V/PI staining showed that overexpression of lnc-HUR1 inhibited apoptosis, while knockdown of lnc-HUR1 promoted apoptosis. Moreover, overexpression of lnc-HUR1 up-regulated the apoptosis inhibitor Bcl-2 and down-regulated the pro-apoptotic factor BAX at both RNA and protein levels. In the CCL4-induced acute liver injury mice model, the expression of Bcl-2 in the liver tissue of lnc-HUR1 transgenic mice was higher than that of the control mice. The data from ChIP assay indicated that lnc-HUR1 reduced the enrichment of p53 on Bcl-2 and BAX promoters. All these results indicated that lnc-HUR1 inhibited the apoptosis by promoting the expression of apoptosis inhibitor Bcl-2 and inhibiting the expression of apoptosis promoting factor BAX. Further studies showed that lnc-HUR1 regulated the transcription of Bcl-2 and BAX in HCT116 cells, but had no effect on the expression of Bcl-2 and BAX in HCT116 p53^-/- cells, indicating that lnc-HUR1 regulates the transcription of Bcl-2 and BAX dependent upon the activity of p53. In conclusion, HBV upregulated lnc-HUR1 can inhibit the apoptosis of hepatoma cells. Lnc-HUR1 inhibits apoptosis by inhibiting the transcriptional activity of p53. These results suggest that lnc-HUR1 plays an important role in the occurrence and development of HBV-related hepatocellular carcinoma.
Animals ; Annexins/pharmacology* ; Apoptosis ; Carcinoma, Hepatocellular/genetics* ; Cell Proliferation ; Hep G2 Cells ; Hepatitis B virus/metabolism* ; Humans ; Liver Neoplasms/genetics* ; Mice ; Poly(ADP-ribose) Polymerase Inhibitors/pharmacology* ; Proto-Oncogene Proteins c-bcl-2/pharmacology* ; RNA, Long Noncoding/metabolism* ; Staurosporine/pharmacology* ; Transforming Growth Factor beta/pharmacology* ; Tumor Suppressor Protein p53/pharmacology* ; bcl-2-Associated X Protein/pharmacology*

Silent information regulator 2-related enzyme 1 (SIRT1) is an aging-related protein activated with aging. Herein, we evaluated the role of SIRT1 in aging-related erectile dysfunction. The expression of SIRT1 was modulated in aged Sprague-Dawley rats following intragastric administration of resveratrol (Res; 5 mg kg^-1), niacinamide (NAM; 500 mg kg^-1) or Res (5 mg kg^-1) + tadalafil (Tad; phosphodiesterase-5 [PDE5] inhibitor; 5 mg kg^-1) for 8 weeks. Then, we determined erectile function by the ratio of intracavernosal pressure (ICP)/mean systemic arterial pressure (MAP). Cavernosal tissues were extracted to evaluate histological changes, cell apoptosis, nitric oxide (NO)/cyclic guanosine monophosphate (cGMP), the superoxide dismutase (SOD)/3,4-methylenedioxyamphetamine (MDA) level, and the expression of SIRT1, p53, and forkhead box O3 (FOXO3a) using immunohistochemistry, terminal deoxynucleotidyl transferase (TdT)-mediated 2'-deoxyuridine 5'-triphosphate (dUTP) nick-end labeling (TUNEL), enzyme-linked immunosorbent assays, and western blot analysis. Compared with the control, Res treatment significantly improved erectile function, reflected by an increased content of smooth muscle and endothelium, NO/cGMP and SOD activity, and reduced cell apoptosis and MDA levels. The effect of Res was improved by adding Tad. In addition, the protein expression of SIRT1 was increased in the Res group, accompanied by decreased p53 and FOXO3a levels. In addition, inhibition of SIRT1 by NAM treatment resulted in adverse results compared with Res treatment. SIRT1 activation ameliorated aging-related erectile dysfunction, supporting the potential of SIRT1 as a target for erectile dysfunction treatment.
Animals ; Male ; Rats ; Cyclic GMP/metabolism* ; Erectile Dysfunction/metabolism* ; Nitric Oxide/metabolism* ; Penile Erection ; Penis/pathology* ; Phosphodiesterase 5 Inhibitors/pharmacology* ; Rats, Sprague-Dawley ; Sirtuin 1/metabolism* ; Superoxide Dismutase/metabolism* ; Tumor Suppressor Protein p53/metabolism*

OBJECTIVE: To investigate the effect of SPARC gene overexpression on the chemotherapeutic sensitivity of AML-MDS cell line SKM-1 to Ara-C and to further explore its mechanism. METHODS: Subjects were divided into 6 groups: SKM-1 cells (Control), Negative control (LV-NC), SPARC overexpression (LV-SPARC), SKM-1 cells+30 ng/ml Ara-C (30 ng/ml Ara-C), LV-NC+30 ng/ml Ara-C and LV-SPARC+30 ng/ml Ara-C. Cell activity was detected by CCK-8 assay, cell cycle distribution and apoptosis were detected by flow cytometry, mRNA expression levels of SPARC, CPBP and MLKL were detected by RT-qPCR, and the expression levels of related protein were detected by Western blot. RESULTS: After co-treatment with SPARC overexpression and Ara-C, the cell viability decreased and apoptosis increased significantly, with obvious up-regulation of Bax and down-regulation of BCL-2 (P<0.05). Compared with the control group, the cell cycle of LV-SPARC+30 ng/ml Ara-C group was significantly arrested in S phase with obvious down-regulation of CDK2 and up-regulation of p27^KIP1 (P<0.05). Compared with LV-SPARC group and 30 ng/ml Ara-C group, the mRNA and protein expression levels of CPBP and MLKL (p-MLKL) were significantly elevated in LV-SPARC+30 ng/ml Ara-C group (P<0.05). In addition, after co-treatment with SPARC overexpression and Ara-C, the protein expression level of p-AKT decreased and the protein expression level of p53 increased (P<0.05). CONCLUSION SPARC overexpression enhanced the sensitivity of SKM-1 cells to Ara-C and promoted cell cycle arrest and apoptosis, the mechanism of which may be related to the regulation of CPBP/MLKL pathway.
Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Cytarabine ; Humans ; Kruppel-Like Factor 6/metabolism* ; Osteonectin/pharmacology* ; Protein Kinases/pharmacology* ; Proto-Oncogene Proteins c-akt/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; RNA, Messenger ; Sincalide/pharmacology* ; Tumor Suppressor Protein p53 ; bcl-2-Associated X Protein/pharmacology*

OBJECTIVES: Our previous study has verified that high level of SET and MYND domain-containing protein 2 (SMYD2) plays an important role in acquiring aggressive ability for liver cancer cells in hepatocellular carcinoma. MiR-200b as a tumor suppressor gene involves in a variety of cancers. This study aims to investigate the correlation between miR-200b and SMYD2 in hepatocellular carcinoma and the underlying mechanism. METHODS: Firstly, the levels of SMYD2 and miR-200b in hepatocellular carcinoma tissues and matched adjacent non-tumor liver tissues were tested with real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. Secondly, we evaluated the interaction between miR-200b and SMYD2 using dual-luciferase reporter assay. Thirdly, we elucidated the effect of miR-200b on SMYD2 and its downstream targets p53/CyclinE1. Finally, we silenced SMYD2 in hepatocellular carcinoma cell lines to investigate its effect on tumor proliferation and cell cycle progression, and further confirmed the correlation among SMYD2 and p53/CyclinE1. RESULTS: Compared with the matched adjacent non-tumor liver tissues, miR-200b was obviously decreased, and SMYD2 was significantly increased in hepatocellular carcinoma (both P<0.05). Spearman's rank correlation revealed that miR-200b expression was negatively correlated with SMYD2 (P<0.01). Computer algorithm and dual-luciferase reporter assay revealed that miR-200b directly targeted and suppressed SMYD2 in HEK 293T cells. The down-regulated miR-200b expression promoted hepatoma cell proliferation (P<0.05) and increased SMYD2 expression(P<0.01), while the up-regulated expression of miR-200b had an opposite effect. The knockdown of SMYD2 suppressed the proliferation of MHCC-97L cells (P<0.01), down-regulated CyclinE1, and up-regulated p53 expression (both P<0.05). CONCLUSIONS MiR-200b is involved in hepatocellular carcinoma progression via targeting SMYD2 and regulating SMYD2/p53/CyclinE1 signaling pathway and may be used as a potential target for hepatocellular carcinoma treatment.
Humans ; Carcinoma, Hepatocellular/pathology* ; Tumor Suppressor Protein p53/metabolism* ; MicroRNAs/metabolism* ; Cell Line, Tumor ; Signal Transduction ; Liver Neoplasms/pathology* ; Cell Proliferation/genetics* ; Histone-Lysine N-Methyltransferase/metabolism*