BackgroundMicroRNA-24 (miR-24) plays an important role in heart failure by reducing the efficiency of myocardial excitation-contraction coupling. Prolonged cardiac hypertrophy may lead to heart failure, but little is known about the role of miR-24 in cardiac hypertrophy. This study aimed to preliminarily investigate the function of miR-24 and its mechanisms in cardiac hypertrophy.

MethodsTwelve Sprague-Dawley rats with a body weight of 50 ± 5 g were recruited and randomly divided into two groups: a transverse aortic constriction (TAC) group and a sham surgery group. Hypertrophy index was measured and calculated by echocardiography and hematoxylin and eosin staining. TargetScans algorithm-based prediction was used to search for the targets of miR-24, which was subsequently confirmed by a real-time polymerase chain reaction and luciferase assay. Immunofluorescence labeling was used to measure the cell surface area, and H-leucine incorporation was used to detect the synthesis of total protein in neonatal rat cardiac myocytes (NRCMs) with the overexpression of miR-24. In addition, flow cytometry was performed to observe the alteration in the cell cycle. Statistical analysis was carried out with GraphPad Prism v5.0 and SPSS 19.0. A two-sided P < 0.05 was considered as the threshold for significance.

ResultsThe expression of miR-24 was abnormally increased in TAC rat cardiac tissue (t = -2.938, P < 0.05). TargetScans algorithm-based prediction demonstrated that CDKN1B (p27, Kip1), a cell cycle regulator, was a putative target of miR-24, and was confirmed by luciferase assay. The expression of p27 was decreased in TAC rat cardiac tissue (t = 2.896, P < 0.05). The overexpression of miR-24 in NRCMs led to the decreased expression of p27 (t = 4.400, P < 0.01), and decreased G0/G1 arrest in cell cycle and cardiomyocyte hypertrophy.

ConclusionMiR-24 promotes cardiac hypertrophy partly by affecting the cell cycle through down-regulation of p27 expression.

Animals ; Cardiomegaly ; genetics ; pathology ; Cell Cycle ; genetics ; physiology ; Cyclin-Dependent Kinase Inhibitor p27 ; genetics ; metabolism ; Male ; MicroRNAs ; genetics ; Myocardium ; metabolism ; Myocytes, Cardiac ; cytology ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo evaluate the effect of Foxo3a gene over-expression on the development of rat ovarian granulosa cells and in prevention of cisplatin-induced ovarian damage in rats.

METHODSRat ovarian granulose cells released mechanically from the ovaries were cultured in vitro and identified with HE staining and immunohistochemical staining for FSHR. A recombinant adenovirus carrying Foxo3a gene was constructed for infecting the granulose cells, and the cell growth and expressions of cyclin D1, p27, Bax, and Bim were detected; the cell apoptosis and cell cycle changes were detected using Hoechst/PI 33342 staining and flow cytometry, respectively. The transfected cells were challenged with cisplatin and the cell apoptosis was detected with flow cytometry.

RESULTSOver 90% of the cultured cells survived and contained more than 95% ovarian granulose cells. Infection of the cells with the recombinant adenovirus resulted in over-expressions of Foxo3a at the mRNA and protein levels at 36 h and 48 h after the infection, respectively. The infected cells showed suppressed proliferation, increased apoptotic rate and cell cycle arrest in G1 phase with increased expressions of Bim, p27, and cyclin D1 but without significant changes in Bax expression. Cisplatin exposure caused a significantly higher apoptosis rate in the infected cells than in the control cells.

CONCLUSIONOver-expression of Foxo3a gene can promote granulose cell apoptosis by increasing Bim expression and cause cell cycle arrest in G1 phase by increasing cyclin D1 and p27 expressions, but can not prevent the toxic effects of cisplatin on ovarian granulosa cells.

Animals ; Apoptosis ; Apoptosis Regulatory Proteins ; metabolism ; Bcl-2-Like Protein 11 ; Cell Cycle Checkpoints ; Cell Proliferation ; Cells, Cultured ; Cisplatin ; adverse effects ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Female ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; genetics ; metabolism ; Gene Expression ; Granulosa Cells ; cytology ; drug effects ; Membrane Proteins ; metabolism ; Proto-Oncogene Proteins ; metabolism ; Rats ; Transfection ; bcl-2-Associated X Protein ; metabolism

OBJECTIVE: To investigate the correlation between cyclin-dependent kinase inhibitor p27kip1 and trastuzumab-resistance in gastric cancer.
 METHODS: We selected HER2-overexpressed human gastric cancer cell line NCI-N87 to establish trastuzumab-resistant NCI-N87/TR cell line by stepwise exposure to different doses of trastuzumab. The 50% inhibitory concentration (IC(50)) of trastuzumab and resistance index (RI) were calculated or analyzed by MTT assay. The expression levels of cdk2 and p27kip1 were detected by Western blot. After the treatment with cdk2 inhibitor (Purvalanol A), the expression levels of relevant proteins in NCI-N87/TR cells were detected by Western blot, and the sensitivity to trastuzumab was analyzed by MTT assay. 
 RESULTS: Compared with NCI-N87 cells, the expression of cdk2 was significantly increased in NCI-N87/TR cells (P<0.001), while the expression of p27kip1 showed a significant decrease (P<0.001). Restoration of the p27kip1 protein expression by cdk2 inhibitor (Purvalanol A) increased the sensitivity of NCI-N87/TR to trastuzumab.
 CONCLUSION Down-regulation of p27kip1 might be a mechanism for triggering trastuzumab resistance to gastric cancer cell line NCI-N87.
Antineoplastic Agents ; pharmacology ; Cell Line, Tumor ; Cyclin-Dependent Kinase 2 ; antagonists & inhibitors ; genetics ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; genetics ; metabolism ; Drug Resistance, Neoplasm ; Humans ; Purines ; pharmacology ; Stomach Neoplasms ; genetics ; metabolism ; pathology ; Trastuzumab ; pharmacology

Although previous reports showed drug-eluting stent (DES) could effectively inhibit neointima formation, in-stent restenosis (ISR) remains an important obstacle. The purpose of this study was to investigate different effects of paclitaxel on proliferation and cell cycle regulators between vascular smooth muscle cells (VSMCs) and vascular endothelial cells (VECs) of rats in vitro. The cultured VSMCs and VECs of rats from the same tissues were examined by using immunohistochemistry, flow cytometry and Western blotting in control and paclitaxel-treated groups. The results showed paclitaxel could effectively inhibit proliferation of VSMCs and VECs. However, as compared with VECs, proliferation of VSMCs in paclitaxel-treated group decreased less rapidly. The percentage of cells in G0-G1 and G2-M phases was reduced, and that in S phase increased after treatment for 72 h. The expression of cyclin D1 and B1, p27 and PCNA in VSMCs of paclitaxel-treated group was up-regulated, but that of p21 down-regulated as compared with VECs. It is concluded that there are significant differences in the expression of cell cycle regulators and proliferation rate between paclitaxel-treated VSMCs and paclitaxel-treated VECs, suggesting that the G1-S checkpoint regulated by paclitaxel may play a critical role in the development of complications of DES, which provides new strategies for treatments of ISR.
Animals ; Blotting, Western ; Cell Cycle ; drug effects ; Cell Cycle Proteins ; metabolism ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cyclin B1 ; metabolism ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Endothelial Cells ; drug effects ; metabolism ; Flow Cytometry ; G1 Phase Cell Cycle Checkpoints ; drug effects ; Immunohistochemistry ; Microscopy, Fluorescence ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; Paclitaxel ; pharmacology ; Proliferating Cell Nuclear Antigen ; metabolism ; Rats ; Tubulin Modulators ; pharmacology

Although it has been suggested that kinesin family member 14 (KIF14) has oncogenic potential in various cancers, including hepatocellular carcinoma (HCC), the molecular mechanism of this potential remains unknown. We aimed to elucidate the role of KIF14 in hepatocarcinogenesis by knocking down KIF14 in HCC cells that overexpressed KIF14. After KIF14 knockdown, changes in tumor cell growth, cell cycle and cytokinesis were examined. We also examined cell cycle regulatory molecules and upstream Skp1/Cul1/F-box (SCF) complex molecules. Knockdown of KIF14 resulted in suppression of cell proliferation and failure of cytokinesis, whereas KIF14 overexpression increased cell proliferation. In KIF14-silenced cells, the levels of cyclins E1, D1 and B1 were profoundly decreased compared with control cells. Of the cyclin-dependent kinase inhibitors, the p27Kip1 protein level specifically increased after KIF14 knockdown. The increase in p27Kip1 was not due to elevation of its mRNA level, but was due to inhibition of the proteasome-dependent degradation pathway. To explore the pathway upstream of this event, we measured the levels of SCF complex molecules, including Skp1, Skp2, Cul1, Roc1 and Cks1. The levels of Skp2 and its cofactor Cks1 decreased in the KIF14 knockdown cells where p27Kip1 accumulated. Overexpression of Skp2 in the KIF14 knockdown cells attenuated the failure of cytokinesis. On the basis of these results, we postulate that KIF14 knockdown downregulates the expression of Skp2 and Cks1, which target p27Kip1 for degradation by the 26S proteasome, leading to accumulation of p27Kip1. The downregulation of Skp2 and Cks1 also resulted in cytokinesis failure, which may inhibit tumor growth. To the best of our knowledge, this is the first report that has identified the molecular target and oncogenic effect of KIF14 in HCC.
Carcinoma, Hepatocellular/*metabolism ; Cyclin-Dependent Kinase Inhibitor p27/genetics/*metabolism ; Cyclins/genetics/metabolism ; *Cytokinesis ; Gene Silencing ; Hep G2 Cells ; Humans ; Kinesin/genetics/*metabolism ; Liver Neoplasms/*metabolism ; Oncogene Proteins/genetics/*metabolism ; Proteasome Endopeptidase Complex/metabolism ; RNA, Messenger/genetics/metabolism ; S-Phase Kinase-Associated Proteins/genetics/metabolism ; *Ubiquitination

OBJECTIVETo explore the effect of downregulation of Tiam1 by siRNA on the esophageal squamous cell carcinoma (ESCC) EC9706 cells, and provide theoretical basis for gene therapy of ESCC using Tiam1 as a molecular target.

METHODSTiam1 siRNA was transfected into EC9706 cells, and expression changes of Tiam1 mRNA and protein after transfection were detected by quantitative real-time PCR and Western blotting. Cell proliferation was analyzed using CCK-8 kit. Cell cycle and apoptosis of the EC9706 cells were assessed by flow cytometry. Cell cycle-related proteins and cell apoptosis-associated proteins were analyzed by Western blotting.

RESULTSCompared with the untreated group and control siRNA group, the relative expression levels of Tiam1 mRNA (1.00 and 0.11 ± 0.02) were not significantly different (P > 0.05). The relative expression levels of Tiam1 mRNA in the Tiam1 siRNA group at 24, 48 and 72 h after transfection were 0.30 ± 0.04, 0.09 ± 0.01 and 0.09 ± 0.006, respectively, significantly lower than that of the untreated group (P < 0.05 for all). The expression level of Tiam1 protein at 24 h after Tiam1 siRNA transfection in the EC9706 cells was 0.11 ± 0.02, significantly lower than that in the un-treated group (0.44 ± 0.05) and control siRNA group (0.44 ± 0.04, P < 0.05 for all). The percentages of G0/G1 cells in the Tiam1 siRNA group, untreated group and control siRNA group were (54.48 ± 2.14)%, (40.69 ± 1.85)% and (41.78 ± 1.31)%, respectively (P < 0.01). The percentages of S phase cells in the Tiam1 siRNA group, untreated group and control siRNA group were (27.18 ± 1.65)%, (32.32 ± 1.15)% and (30.35 ± 1.09)%, respectively (P < 0.01). The expression levels of cyclin D1 protein in the untreated group, control siRNA group and Tiam1 siRNA group were 0.43 ± 0.02, 0.41 ± 0.01 and 0.11 ± 0.02, respectively (P < 0.05). The expression levels of p27 protein in the untreated group, control siRNA group and Tiam1 siRNA group were 0.10 ± 0.01, 0.09 ± 0.02 and 0.20 ± 0.02, respectively (P < 0.05). The ratios of early apoptotic cells in the untreated group, control siRNA group and Tiam1 siRNA group were (10 ± 0.9)%, (10 ± 0.5)% and (27 ± 0.7)%, respectively (P < 0.01). The expression levels of Mcl-1 protein in EC9706 cells of untreated group, control siRNA group and Tiam1 siRNA group were 0.47 ± 0.12, 0.48 ± 0.13 and 0.16 ± 0.02, respectively (P < 0.05). The expression levels of Bcl-2 protein in EC9706 cells of the untreated group, control siRNA group and Tiam1 siRNA group were 0.49 ± 0.08, 0.50 ± 0.05 and 0.04 ± 0.03, respectively (P < 0.05). The caspase-3 activities in the untreated group, control siRNA group and Tiam1 siRNA group were 2.3 ± 0.09, 2.3 ± 0.10 and 16.0 ± 1.50, respectively; and that of caspase-9 were 2.3 ± 0.08, 2.3 ± 0.11 and 14.5 ± 0.9, respectively (P < 0.05 for all).

CONCLUSIONSTiam1 siRNA can significantly inhibit the proliferation of esophageal cancer EC9706 cells, induce cell cycle arrest and cell apoptosis. These effects are related to the regulation of the expressions of cell cycle-related genes (cyclin D1 and p27) and cell apoptosis-related genes (Mcl-1, Bcl-1, caspase-3 and caspase-9) by Tiam1 siRNA.

Apoptosis ; Carcinoma, Squamous Cell ; genetics ; metabolism ; pathology ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Cell Cycle Checkpoints ; Cell Line, Tumor ; Cell Proliferation ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Down-Regulation ; Esophageal Neoplasms ; genetics ; metabolism ; pathology ; Guanine Nucleotide Exchange Factors ; genetics ; metabolism ; Humans ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; T-Lymphoma Invasion and Metastasis-inducing Protein 1 ; Transfection

Uchl1 was found to be involved in spermatocyte apoptosis. The aim of the present study was to test whether Uchl1 and its associated proteins Jab1 and p27(kip1) were involved in spermatogenic damages in response to heat-stress in cryptorchidism. Hematoxylin and eosin (HE) staining and DNA end labeling (TUNEL) were used to observe morphological and apoptotic characteristics of spermatogenic cells; Immunohistochemical analysis was used to detect changes of Uchl1 and its associated proteins Jab1 and p27(kip1) in response to heat-stress from cryptorchidism leading to spermatocyte losses; And protein affinity analysis (pull-down) and immunofluorescence co-localization were used to verify the relevance among the three proteins in spermatocytes. The results showed that, Jab1 and p27(kip1), in parallel to Uchl1, increased in spermatocytes of apoptotic appearances in response to heat-stress, but not in multinucleated giant cells; Jab1 bound to Uchl1 in testis protein extracts, and co-localized with Uchl1 and p27(kip1) specifically in spermatocytes with apoptotic appearances. These results suggest that the accumulation of Uchl1 protein is involved in the heat-stress-induced spermatocyte apoptosis through a new pathway related with Jab1 and p27(kip1), but not the formation of multinucleated giant cells.
Animals ; Apoptosis ; COP9 Signalosome Complex ; Cryptorchidism ; pathology ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Hot Temperature ; Intracellular Signaling Peptides and Proteins ; metabolism ; Male ; Mice ; Peptide Hydrolases ; metabolism ; Spermatocytes ; cytology ; metabolism ; Stress, Physiological ; Ubiquitin Thiolesterase ; metabolism

OBJECTIVE: To explore new hallmarks affecting the prognosis of patients with laryngeal squamous cell carcinoma (LSCC) via investigating the expression of CyclinE and p27 in LSCC tissues. METHOD: The expression of CyclinE and p27 was detected via Elivision immunohistochemical staining in 160 LSCC tissues and 20 normal laryngeal tissues (NLT). The relationship between CyclinE/ p27 and LSCC/ NLT was analyzed via Log-rank analysis. The relationship of CyclinE and p27 protein was statistically analyzed by spearman correlation analysis. The relationship between CyclinE/p27 and clinical-pathology-factors of patients with LSCC, such as age, gender, tumor site, diameter, differentiation, lymph node metastasis and PTNM stage were analyzed by Chi-square test. The relationship between clinical-pathology-factors, CyclinE, p27 and overall survival time of patients with LSCC was analyzed via Cox multiplicity and Kaplan-Meier survival analysis. A significant difference was recognized by P<0.05. RESULT: In LSCC the positive rates of CyclinE and p27 protein was 62.50% and 41.25% respectively (P<0.05). In NLT the positive rates of CyclinE and p27 protein was 35% and 70% respectively (P<0.05). The expression of CyclinE or p27 protein was closely correlated with lymph node metastasis, PTNM stage of patients with LSCC (P<0.05). The expression of CyclinE and p27 had no significant correlations with patients' gender, age and tumor site, diameter differentiation (P>0.05 for all). A negative correlation was found between the expression of CyclinE and p27 protein, r= -0.767(P<0.05). Kaplan-Meier survival analysis showed that the overall survival rate of patients with LSCC was 36.9% (P<0.05). The 5-year survival rate in positive group of CyclinE was 8%, in negative group was 80% (P<0.05). On the contrary, the 5-year survival rate of patients with LSCC in positive group of p27 protein was 77.27%, the rate was 5.32% in negative group (P<0.05). Cox multivariate regression analysis revealed that lymph node metastasis, PTNM stage, CyclinE and p27 were independent risk factors of prognosis for patients with LSCC. CONCLUSION It is the molecular basis underlying the development and invasion/ metastasis of LSCC that activation of CyclinE gene accompanying inactivation of p27 gene. It is very important of co-detecting CyclinE and p27 protein to predict the prognosis of patients with LSCC.
Carcinoma, Squamous Cell ; metabolism ; pathology ; Cyclin E ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Female ; Head and Neck Neoplasms ; metabolism ; pathology ; Humans ; Laryngeal Mucosa ; metabolism ; pathology ; Laryngeal Neoplasms ; metabolism ; pathology ; Lymphatic Metastasis ; Male ; Middle Aged ; Oncogene Proteins ; metabolism ; Prognosis ; Squamous Cell Carcinoma of Head and Neck ; Survival Rate

OBJECTIVETo investigate and compare the effects and mechanisms of three functional parts of Dahuang Zhechong Pill (DHZCP), including drugs with the function of removing blood stasis and promoting blood circulation (FP-I), drugs with the function of expelling heat and moistening dryness (FP-II), and drugs with the function of nourishing yin and replenishing blood (FP-III) of DHZCP, on platelet-derived growth factor (PDGF)-stimulated vascular smooth muscle cells (VSMCs) proliferation with the method of serum pharmacology.

METHODSVSMCs proliferation of rat was assayed by measuring the cell viability with the 3-(4, 5-dimethylthiazol-2yl)-2, 5-diphenyltetrazolium bromide (MTT) method. DNA synthesis in VSMCs was examined by detecting 5'-bromo-2'-deoxyuridine incorporation with the immunocytochemical method. Cycle of VSMCs was evaluated with flow cytometry. Expression of cyclin D1, p27, PKCα, and phosphorylated extracellular signal regulated kinase 1/2 (ERK1/2) was quantified by the Western blotting method.

RESULTSThe FP-I and FP-III containing serum was capable of inhibiting PDGF-stimulated proliferation and DNA synthesis of VSMCs, arrested VSMCs in G phase, downregulated cyclin D1, and upregulated p27 expression (P <0.01 or P <0.05). The FP-I and FP-III containing serum also inhibited the PDGF-induced phosphorylation of tyrosine of ERK1/2 and PKCα expression (P <0.01 or P <0.05).

CONCLUSIONSFP-I and FP-III of DHZCP are able to inhibit VSMCs proliferation via interrupting PKCα-ERK1/2 signaling, modulating the expression of cell cycle proteins to result in arresting the cells in G phase. The inhibitory effect is mainly related to the function of removing blood stasis and promoting blood circulation, slightly to the function of nourishing yin and replenishing blood, but not to the function of expelling heat and moistening dryness.

Animals ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; DNA ; biosynthesis ; Drugs, Chinese Herbal ; pharmacology ; Enzyme Activation ; drug effects ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; MAP Kinase Signaling System ; drug effects ; Male ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; enzymology ; Platelet-Derived Growth Factor ; pharmacology ; Protein Kinase C-alpha ; metabolism ; Rats ; Rats, Sprague-Dawley ; Serum ; metabolism

Adult ; Aged ; Aged, 80 and over ; Breast Neoplasms ; metabolism ; pathology ; Carcinoma ; metabolism ; pathology ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Female ; Humans ; Lymphatic Metastasis ; Middle Aged ; Neoplasm Staging ; Phosphorylation ; Prognosis ; S-Phase Kinase-Associated Proteins ; metabolism ; Threonine ; metabolism