OBJECTIVETo investigate the expression of five kinds of cyclins in hepatocellular carcinoma (HCC) and their association with degree of tumor differentiation, metastasis and infection of hepatitis B virus (HBV).

METHODSThe HCC tissue microarrays were composed of those from 273 cases of HCC tissues, 144 surrounding-tumor liver tissues and 10 normal liver tissues obtained from autopsy. The diameter of each specimens on tissue microarrays was 2.0 mm. Immunohistochemistry was used to detect the expression of cyclin A, cyclin B, cyclin D1, cyclin D3 and cyclin E on HCC tissue microarrays. The association of the expression of these cyclins with the infection rate of HBV was also analyzed.

RESULTSThree paraffin-embedded HCC tissue microarrays were successfully constructed, including 136, 143 and 148 tissue spots, respectively. The positive rates of cyclins in 273 cases of HCC were cyclin A 52.7%, cyclin B 45.4%, cyclin D1 35.9%, cyclin D3 44.3% and cyclin E 23.1%; while the figures in 144 surrounding-tumor tissues were 8.3%, 5.6%, 4.9%, 6.3% and 1.4%, respectively. In 10 normal liver tissues these cyclins exhibited negative staining, with the exception that cyclin D1 was positive in one case of normal liver tissue. The positive rate of cyclins in HCC were significant higher than those in surrounding-tumor liver tissues (P < 0.01), in HCC tissues with histological grade II and III, the cyclins expression were stronger than that in grade I (P < 0.05). The positive rates of cyclins, except cyclin A in HCC with portal vein invasion were higher than those without portal vein invasion (P < 0.01). Infection of HBV did not have significant relationship with the expression of cyclins (P > 0.05).

CONCLUSIONCyclins in different cell cycles overexpressed at varied levels in hepatocellular carcinoma, and the increased expression of cyclins may shorten the tumor cell cycle phase, accelerate cell proliferation, and have a close relationship with HCC aggressiveness.

Carcinoma, Hepatocellular ; chemistry ; Cyclin A ; analysis ; Cyclin B ; analysis ; Cyclin D1 ; analysis ; Cyclin D3 ; Cyclin E ; analysis ; Cyclins ; analysis ; Hepatitis B ; metabolism ; Humans ; Immunohistochemistry ; Liver Neoplasms ; chemistry

OBJECTIVES: The molecular mechanisms that regulate cardiomyocyte cell cycle and terminal differentiation in humans remain largely unknown. To determine which cyclins, cyclin dependent kinases (CDKs) and cyclin kinase inhibitors (CKIs) are important for cardiomyocyte proliferation, we have examined protein levels of cyclins, CDKs and CKIs during normal atrial development in humans. METHODS: Atrial tissues were obtained in the fetus from inevitable abortion and in the adult during surgery. Cyclin and CDK proteins were determined by Western blot analysis. CDK activities were determined by phosphorylation amount using specific substrate. RESULTS: Most cyclins and CDKs were high during the fetal period and their levels decreased at different rates during the adult period. While the protein levels of cyclin D1, cyclin D3, CDK4, CDK6 and CDK2 were still detectable in adult atria, the protein levels of cyclin E, cyclin A, cyclin B, cdc2 and PCNA were not detectable. Interestingly, p27KIP1 protein increased markedly in the adult period, while p21CIP1 protein in atria was detectable only in the fetal period. While the activities of CDK6, CDK2 and cdc2 decreased markedly, the activity of CDK4 did not change from the fetal period to the adult period. CONCLUSION: These findings indicate that marked reduction of protein levels and activities of cyclins and CDKs, and marked induction of p27KIP1 in atria, are associated with the withdrawal of cardiac cell cycle in adult humans.
Adult ; Age Factors ; Animal ; Blotting, Western ; Cell Cycle ; Cells, Cultured ; Comparative Study ; Cyclin A/analysis ; Cyclin B/analysis ; Cyclin D1/analysis ; Cyclin E/analysis ; Cyclin-Dependent Kinases/analysis* ; Cyclins/analysis* ; Female ; Fetal Development ; Heart Atrium/growth & development* ; Heart Atrium/embryology ; Heart Atrium/cytology* ; Heart Atrium/chemistry ; Human ; Male ; Middle Age ; Myocardium/chemistry* ; Rats ; Rats, Sprague-Dawley ; Substances: Cyclin D1 ; Substances: Cyclins ; Substances: Cyclin-Dependent Kinases ; Substances: Cyclin E ; Substances: Cyclin B ; Substances: Cyclin A

OBJECTIVETo investigate the expressions of cyclin E, cyclin dependent kinase 2 (CDK-2) and cyclin-dependent kinase inhibitor p57(KIP2) in human gastric cancer, and to evaluate the relationships between protein levels and clinicopathological parameters.

METHODSWestern blot was used to measure the expressions of cyclin E, CDK-2 and p57(KIP2) proteins in the surgically resected gastric carcinoma, adjacent normal mucosa and metastatic lymph nodes from 36 patients.

RESULTSCyclin E and CDK-2 protein levels were higher in gastric cancer tissues in comparison with normal tissues (P < 0.05). Overexpression of cyclin E was correlated with lymph node involvement, poor histological grade and serosa invasion (P < 0.05). Overexpression of CDK-2 was correlated with lymph nodes involvement (P < 0.05). No statistically significant difference between cyclin E and CDK-2 expression was found when samples were stratified according to tumor size (P > 0.05). Expression of cyclin E and CDK-2 showed a positive linear correlation (r = 0.451, P = 0.01). Protein levels of p57(KIP2) were lower in gastric cancer tissues than in the normal mucosa (P < 0.05). Decreased expression of p57(KIP2) was correlated with lymph node involvement (P < 0.05). No statistically significant difference in p57(KIP2) expression was found when sample were stratified according to tumor size, histological grade or serosa invasion (P > 0.05). In metastatic lymph nodes, expression of cyclin E was increased and the expression of p57(KIP2) decreased.

CONCLUSIONOverexpressions of cyclin E, CDK-2 and downregulated expression of p57(KIP2) may play important roles in tumorigenesis and metastatic potential of gastric cancer.

Blotting, Western ; CDC2-CDC28 Kinases ; Cyclin E ; analysis ; physiology ; Cyclin-Dependent Kinase 2 ; Cyclin-Dependent Kinase Inhibitor p57 ; Cyclin-Dependent Kinases ; analysis ; physiology ; Humans ; Lymphatic Metastasis ; Nuclear Proteins ; analysis ; physiology ; Protein-Serine-Threonine Kinases ; analysis ; physiology ; Stomach Neoplasms ; chemistry ; pathology

BACKGROUND: Cyclin E plays a pivotal role in the regulation of G1-S transition and could consequently be a deregulated molecule in tumors. The activity of the cdk2-cyclin E complex is increased by degradation of cdk inhibitor p27kip1. Little is known about the expression and prognostic significance of cyclin E and p27 in non-small cell lung cancer(NSCLC). MATERIAL AND METHOD: The expression of cyclin E and p27 in eighty-one cases of resected stage I NSCLC tissues and its relation to major clinico-pathological factors, including histology, differentiation, size of tumor, pleural invasion and survival rate were studied and analyzed. Immunohistochemical analysis with monoclonal antibodies specific for cyclin E and p27 were performed by ABC method. RESULT: Expression rates of cyclin E and p27 in stage I NSCLC tissues were 29.6% and 28.4% respectively. Cyclin E was expressed higher in cases of pleural invasion(p=0.04), and p27 was expressed higher in diameter of tumor less than 3cm(p=0.015). The 5-years survival rate was lower in cases of positive expression of cyclin E than in cases of negative expression of cyclin E(44.4% vs 68.2%, p=0.015), and the 5-years survival rate was 72.2% in positive expression of p27 and 56.2% in negative expression of p27(p=0.09). The 5-years survival rate was higher in negative expression of cyclin E and positive expression of p27 than in cases of positive expression of cyclin E and negative expression of p27 (73.5% vs 36.3%, p=0.0029). In multivariate analysis, expression of cyclin E was an unfavorable prognostic factor(RR=3.578, p=0.006) and p27 was a favorable prognostic factor(RR=0.183, p=0.019) independently. CONCLUSION: Cyclin E and p27 may play a pivotal role for the biological behavior of stage I NSCLC, so that the expressions of cyclin E and p27 may be new prognostic markers.
Antibodies, Monoclonal ; Carcinoma, Non-Small-Cell Lung* ; Cyclin E* ; Cyclins* ; Lung ; Multivariate Analysis ; Survival Rate

OBJECTIVETo investigate the effects of p57(kip2) and cyclinE proteins on the genesis and progression of human pancreatic cancer.

METHODSThe expression of p57(kip2) and cyclinE proteins in tumor tissues and adjacent tissues of pancreatic cancer in 32 patients was detected by SP immunohistochemical technique.

RESULTSThe p57(kip2) protein positive-expression rate in tumor tissues of pancreatic cancer was 46.9%, which was lower than that in adjacent pancreatic tissue (P < 0.05). The p57(kip2) protein positive-expression correlated significantly with tumor cell differentiation (P < 0.05) and did not correlate significantly with lymph node metastasis (P > 0.05). The cyclinE positive-expression rate in tumor tissues was 68.8%, which was higher than that in adjacent pancreatic tissues (P < 0.05). The cyclinE positive-expression also correlated significantly with tumor cell differentiation and lymph node metastasis (P < 0.05). The cyclinE protein positive-expression rate in the tumor tissues of the p57(kip2) protein positive-expression group was lower than that in the p57(kip2) protein negative-expression group, and there were no significant correlation between the two groups (r = -0.112, P > 0.05).

CONCLUSIONDecreased expression of the p57(kip2) protein and/or over-expression of the cyclinE protein may play an important role in the genesis and progression of human pancreatic cancer.

Adult ; Aged ; Cyclin E ; analysis ; Cyclin-Dependent Kinase Inhibitor p57 ; Female ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Nuclear Proteins ; analysis ; Pancreatic Neoplasms ; chemistry ; pathology

PURPOSE: Cyclin E is a key regulatory protein in the G1-S transition during the cell cycle. The correlations between cyclin E protein and the clinical features of breast cancer were investigated in order to evaluate its clinical utility in invasive breast cancer. METHODS: An immunohistochemical assay for cyclin E was performed in 101 consecutive invasive breast cancers. The correlation between cyclin E expression and the clinicobiological parameters including patient survival was analyzed. RESULTS: Cyclin E expression was observed in 50 patients (49.5%). The scoring of the cyclin E expression level was divided into low (<25%) and high (>or=25%). In high nuclear grade tumors, cyclin E overexpression was much higher than that in low nuclear grade tumors (P=0.049). In the younger age group (<50 yrs), cyclin E expression was significantly higher than the older age group (P= 0.016). No significant correlation was observed between cyclin E and the tumor size, lymph node status, hormonal receptor status, histological grade, mitotic index and Ki67. In multivariate analysis, only the lymph node status was significantly associated with the patients' outcome (P= 0.002). CONCLUSION: Cyclin E overexpression did not have prognostic impact on the patients' survival rate in invasive breast cancer. In high nuclear grade tumors, the cyclin E expression level was much higher. The definite value of cyclin E as a clinicobiologic marker should be further investigated by prospective studies with other cell regulatory proteins.
Breast Neoplasms* ; Breast* ; Cell Cycle ; Cell Proliferation ; Cyclin E* ; Cyclins* ; Humans ; Lymph Nodes ; Mitotic Index ; Multivariate Analysis ; Prognosis ; Survival Rate

Hexamethylene bisacetamide (HMBA) is referred as a differentiation-inducer for the clinical treatment of acute myeloid leukemia and myelodysplastic syndrome. However, the molecular mechanism of the effects of HMBA on myeloid leukemic cells remains unknown. In this study, the effects of HMBA on cell cycle and expression of cell cycle regulatory proteins in HL-60 cell were investigated in order to explore its pharmacological mechanism. The altered distribution of cell cycle and expression of its regulatory proteins (cyclin D, cyclin E and p27) in HL-6 0 cell induced by HMBA were analyzed by flow cytometry. The effects on transcription for mRNA of CKI p15, p16 and p27 in HL-60 cell were further studied by RT-PCR. The results showed that HMBA could mainly commit HL-60 cell to G0/G1 arrest and the significantly decreased endocytic cyclin E protein and increased cyclin D/p27 protein after HMBA treatment were found. There was no expression of p15, p16 mRNA in untreated HL-60 cell and 3 mmol/L of HMBA could make them expressed after exposed for 24 h or 48 h respectively. The expression of p27 mRNA was positive and no obviously different in untreated HL-60 cells exposed for 24 h, 48 h and 72 h. These results suggested that one of the pharmacological mechanisms of HMBA was to elevate the expression of p27 and reduce the cyclin E expression as well as to activate the expression of p15, p16 gene mRNA, that arrested cell at G0/G1 and exerted its effects of anti-proliferation.
Acetamides ; pharmacology ; Antineoplastic Agents ; pharmacology ; Cell Cycle ; drug effects ; Cell Cycle Proteins ; analysis ; genetics ; Cyclin D ; Cyclin E ; analysis ; Cyclin-Dependent Kinase Inhibitor p15 ; Cyclin-Dependent Kinase Inhibitor p27 ; Cyclins ; analysis ; Genes, p16 ; HL-60 Cells ; Humans ; RNA, Messenger ; analysis ; Tumor Suppressor Proteins ; analysis ; genetics

The threshold of cyclin E expression at G1/S boundary is a characteristic feature of cell cycle progressing. In this study, we tried to develop a quantitative approach to analyze cyclin E threshold by multiparameter flow cytometry. The expression of cyclin E in exponentially growing MOLT-4 cells was detected under different photomultiplier tube (PMT) voltages by cyclin E/DNA multiparameter flow cytometry. Additionally, cyclin E was detected in cells which were treated with caffeine and cycloheximide (CHX) under the same PMT voltage. Moreover, the expression of cyclin E in MOLT-4 cells was compared with that in JURKAT cells. Cyclin E threshold was quantified by formula B2/AxC (A, B, C indicates the minimum, threshold, and maximum of cyclin E fluorescence intensity, respectively). Results showed that in MOLT-4 cells, cyclin E threshold calculated by formula B2/AxC was invariable under different PMT settings. It was decreased in cells treated with caffeine and remained changeless in cells treated with cycloheximide. Cyclin E threshold in JURKAT cells was much lower than that in MOLT-4 cells. It was suggested that Formula B2/AxC we firstly set up could be used to analyze cyclin E expression threshold quantitatively.
Caffeine/pharmacology ; Cell Cycle/*physiology ; Cell Line, Tumor ; Cyclin E/*analysis ; Cycloheximide/pharmacology ; DNA, Neoplasm/*analysis ; Flow Cytometry/methods ; Jurkat Cells ; Leukemia, Lymphoid/pathology

There is considerable need for reliable prognostic markers to guide clinicians in management decisions for the breast cancer. The cell cycle is governed by a family of cyclin-dependent kinases(Cdks), regulated by associated cyclin p27, a cyclin dependent kinase inhibitors, regulates progression from GI into S phase by inhibiting cyclin/cdks complex. This study was performed to evaluate the association between p27 expression, determined by immunohistochemical stain, and various histopathologic features in breast cancer. It was also determined whether p27 expression had the significance as the prognostic factorin the breast cancer patients. 45 patients who got the relatively good preserved paraffin blocks among the 100 patients was chosen for immunohistochemical staining against p27, cyclin E, c-erbB2, cathepsin D and p53 and reexamined their unclear and histological grades from Jan. 1989 through Dec. 1992. As a results, the patients with negative expression of p27 had more metastatic axillary nodes than those with positive expression. (5.87+/-1.87 vs 1.14+/-0.54, p=0.021) p27 negative group got worse nuclear grade than p27 negative group but beyond statistical significance. (48.4% vs 28.6%, p=0.281) On univariate analysis, primary tumor size, status of axillary nodes and the expression of p27 were the significant prognostic factors affecting overall survival rates. In particular, p27 positive group had better outcomes on 5 years survival rate than p27 negative group. (92.31+/-7.39% vs 73.33+/-8.07%, p=0.0441) but didn't affect the disease free survival with statistical significance. On multivariate analysis, the primary tumor size and axillary node were significant prognostic factors on overall and disease free survival. In conclusion, despite relativeiy small size of this study group, considering that p27 negative group got the more metastatic node and worse overall survival, 27 expression might be a novel prognostic indicator in the breast cancer.
Breast Neoplasms* ; Breast* ; Cathepsin D ; Cell Cycle ; Cyclin E* ; Cyclins* ; Disease-Free Survival ; Humans* ; Multivariate Analysis ; Paraffin ; Phosphotransferases ; S Phase ; Survival Rate

Acetamides ; pharmacology ; Antineoplastic Agents ; pharmacology ; CD11b Antigen ; analysis ; Cell Differentiation ; drug effects ; Cyclin D ; Cyclin E ; analysis ; Cyclins ; analysis ; G1 Phase ; Genes, Retinoblastoma ; Genes, bcl-2 ; Genes, myc ; HL-60 Cells ; Humans ; Leukemia, Myeloid ; pathology ; Proliferating Cell Nuclear Antigen ; analysis ; RNA ; analysis ; Reverse Transcriptase Polymerase Chain Reaction ; U937 Cells