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

BACKGROUND: Inactivation of the retinoblastoma protein (pRb) is a mechanism by which tumor cells can subdue normal growth control. Among the molecules involved in control of pRb phosphorylation, cyclin D1 and cyclin E have been found to be deregulated and overexpressed in various types of cancers. METHODS: Immunohistochemical stains for pRb, p16, cyclin D1 and cyclin E were performed in 73 cases of infiltrating duct carcinomas of the breast. In addition to analysis of their expression rates, the relationships between their expressions and the clinicopathologic parameters were evaluated. RESULTS: pRb, p16, cyclin D1 and cyclin E were positive in 64.7% (44 out of 68 cases), 24.6% (15 out of 61 cases), 43.8% (32 out of 73 cases) and 61.6% (45 out of 73 cases), respectively. Their expression rates were not significantly associated with clinicopathologic prognostic factors. 33 out of 38 cases with p16-negative reactions were pRb positive, while 10 out of 15 cases with pRb-negative reactions were p16 positive. There was a significant inverse relationship between pRb and p16 expressions (P<0.005). 25 out of 32 cases with cyclin E-positive reactions were cyclin D1-positive, and 25 out of 45 cases with cyclin D1-positive reactions were cyclin E-positive. A statistically significant association was observed between cyclin D1 and cyclin E expressions (P<0.05). CONCLUSIONS: The main mechanism during tumorigenesis of breast carcinoma depends on the cyclin D1/p16/pRb pathway, but cyclin E might play a role in the absence of cyclin D1. The inverse correlation between the pRb and p16 expressions may represent one of the important mechanisms in tumorigenesis, as well.
Breast Neoplasms ; Breast* ; Carcinogenesis ; Coloring Agents ; Cyclin D1* ; Cyclin E* ; Cyclins* ; Phosphorylation ; Retinoblastoma ; Retinoblastoma Protein

Recently, many natural medicines, whose advantages are less side effects and possibility of long-term use, have been studied for their capacity, their anti-bacterial and anti-inflammatory effects and regenerative potential of periodontal tissues. Cervi Parvum Cornu(CPC) have been traditionally used as an hale, growth, hematogenous, anti-aging, back pain in Eastern medicine. The purpose of present study was to investigate the effects of CPC extract on cell cycle progression and its molecular mechanism in human fetal osteoblasts. CPC extracts (10 microgram/ml) increased cell proliferation in the human fetal osteoblasts as compared to non-supplemented control. There was no significant change in the G1 and S phase, but a increase in the G2/M phase in 10 microgram/ml and 100 microgram/ml of CPC extracts group as compared to non-supplemented control. The protein expression of cyclin E, cdk 2, cyclin D, cdk 4, and cdk 6 was higher than that of control group. The level of p21 was lower than that of control. But that of pRb and p16 was not distinguished from control. These results indicate that the increase of cell proliferation by CPC extracts may be due to the increased expression of cyclin E , cdk 2, cyclin D, cdk 4 and cdk 6, and the decreased expression of p21 in human fetal osteoblasts .
Back Pain ; Cell Cycle* ; Cell Proliferation ; Cyclin D ; Cyclin E ; Cyclins ; Humans* ; Osteoblasts* ; S Phase

PURPOSE: To evaluate the clinical impact of the altered expression of cell cycle regulators in stage I and II breast cancers. MATERIALS AND METHODS: The interaction between cyclin D1/E and p27Kip1 expressions were analyzed using tissue microarray (TMA) technology in 133 breast cancers. Data from the immunohistochemical assays of 3 molecules were merged, and analyzed, with a Ki67 labeling index of the same tumors. RESULTS: Cyclin D1 was expressed in 72 breast carcinomas (54.1%) and cyclin E in 60 (45.1%) out of the 133 breast carcinomas. Expressions of cyclin D1 and cyclin E were inversely related to each other, and significantly associated with the estrogen receptor (ER) expression and differentiation of the breast carcinoma. The expression of cyclin E was significantly decreased in tumors expressing cyclin D1 (p=0.022). There was a trend for cyclin D1 expression to increase in tumors expressing p27Kip1 (p=0.053), but the expression of cyclin E did not correlate with p27Kip1 expression. The Ki67 labeling index was markedly increased in tumors expressing cyclin E, whereas it was significantly decreased in the cyclin D1 or p27Kip1 expressing-tumors. From survival analysis, cyclin E expression was the only significant variable for the prediction of poor survival. CONCLUSION: The abnormal expressions of cell cycle regulatory molecules are prevalent, and interrelated with each other in breast cancer. Integration of TMA technology allowed a high-throughput analysis for correlating molecular the in situ findings, with the clinico-pathologic information. Among the three molecules studied, the cyclin E had a prognostic implication for stage I and II breast cancer.
Breast Neoplasms* ; Breast* ; Cell Cycle ; Cyclin D1* ; Cyclin E* ; Cyclins* ; Estrogens ; Prognosis

Cell growth characterized by cell cycle progression is regulated by cyclin-dependent kinase (CDK). CDKs are activated by binding cyclins such as cyclin A, cyclin B, cyclin D1, and cyclin E. Proliferative indices such as Ki-67 and proliferative cell nuclear antigen (PCNA) are known to be correlated with the mitotic index and were reported to have increased in the lesional psoriatic skin in previous reports. In this study, we investigated the expression of cyclins and proliferative indices (cyclin A, cyclin B, cyclin D1, cyclin E, Ki-67, and PCNA) in the psoriatic epidermis before and after cyclosporin therapy (3mg/kg/day 12 wks). Cyclin A, Ki-67, and PCNA were 1+ to 2+ positive before treatment but showed positive staining in only a few cells after treatment. Cyclin B and cyclin E were also moderate-to-strongly positive before treatment and became only weakly positive after treatment. Cyclin D1 was expressed only in a few cells and was negative after treatment. Taken together, cyclosporin may have an anti-proliferative effect on keratinocytes which was demonstrated by reduction of the proliferative indices such as Ki-67 and PCNA. The mechanism of the anti-proliferative effect may be through the inhibition of the cell cycle progression. Cyclin A, cyclin B and cyclin E are amongst the targeted cell cycle modulators, whereas cyclin D1 seems to be less induced in the lesional psoriatic epidermis, both before and after cyclosporin therapy.
Cell Cycle ; Cyclin A ; Cyclin B ; Cyclin D1 ; Cyclin E ; Cyclins* ; Cyclosporine* ; Epidermis* ; Keratinocytes ; Mitotic Index ; Phosphotransferases ; Proliferating Cell Nuclear Antigen ; Psoriasis ; Skin

PURPOSE: Cyclins, and their associated cyclin dependent kinases, regulate progression of the cell cycle through the G1 phase and into the S-phase during the DNA replication process. Cyclin E regulation is an important event in cell proliferation. Despite its importance, abnormalities of these genes and their protein products have yet to be found in lits asoociation with lung cancer. MATERIALS AND METHODS: The relationships between expression of cyclin A, cyclin B1, cyclin D1, cyclin D3, and cyclin E and clinicopathologic factors were investigated in 103 cases with non-small cell carcinomas, using immunohistochemical analysis. RESULTS: The positive immunoreactivity was observed in 51 cases (50%) for cyclin A, 33 cases (32%) for cyclin B1, 83 cases (81%) for cyclin D1, 19 cases (18%) for cyclin D3, and 11 cases (11%) for cyclin E. Expression of cyclin E was significant for lymph node metastasis (p=0.004, Chi-square test). There was no relationship between cyclin A, B1, D1, and E and histological typing, tumor size, lymph node metastasis, or pathological tumor, node and metastasis staging. CONCLUSION: These findings suggest that the expression of cyclin E played a role, to some degree, in the lymph node metastasis.
Adenocarcinoma ; Carcinoma, Squamous Cell ; Cell Cycle ; Cell Proliferation ; Cyclin A ; Cyclin B1 ; Cyclin D1 ; Cyclin D3 ; Cyclin E ; Cyclin-Dependent Kinases ; Cyclins ; DNA Replication ; G1 Phase ; Lung ; Lung Neoplasms ; Lymph Nodes ; Neoplasm Metastasis

OBJECTIVE: To determine whether Indole-3-carbinol (I3C) can enhance the inhibitory effect of genistein on a human uterine leiomyoma cells. METHODS: Five uterine leiomyoma tissues were obtained from hysterectomies conducted on the benign diseases and cultured primarily. MTS reduction assay was carried out to determine the viability of human uterine leiomyoma cells. Cell cycle analysis for I3C and genistein treated human uterine leiomyoma cells was done by Fluorescent activated cell sorter (FACS) analysis. To detect the presence and expression of cell cycle related proteins was done by Western blot analysis. RESULTS: I3C and genistein induced growth inhibition in a dose dependent manner, treatment with 100 micro mol/L I3C and 100 micro mol/L genisten blocked 60% cell growth. FACS results showed that treatment with the I3C and genistein increased the percentage of cells in G2/M phase and decreased S phase. From Western blot analysis it revealed I3C and genistein induced the expression of p53, p21, and p27 increasing. Reduced expression of cyclin B1 and cyclin E were detected in treatment with I3C and genistein. The expression levels of these proteins correlate with G2/M cell cycle arrest. Activation of caspase pathway and fragmentation of PARP did not take place. CONCLUSIONS: These results demonstrate that I3C enhances genistein-mediated uterine leiomyoma cell growth inhibition through the cell cycle arrest at G2/M phase by decreasing the production of cyclin B1. Because of the synergistic effect of I3C and genistein, the potential exists for the therapeutic efficacy of each phytochemical when used in combination.
Blotting, Western ; Cell Cycle ; Cell Cycle Checkpoints ; Cyclin B1 ; Cyclin E ; Cyclins ; Genistein* ; Humans* ; Hysterectomy ; Leiomyoma* ; S Phase

Retinoic acid plays an important role in the regulation of cell growth and differentiation. In our present study, we evaluated the effects of all-trans retinoic acid (RA) on cell proliferation and on the cell cycle regulation of human gingival fibroblasts (HGFs). Cell proliferation was assessed using the MTT assay. Cell cycle analysis was performed by flow cytometry, and cell cycle regulatory proteins were determined by western blot. Cell proliferation was increased in the presence of a 0.1 nM to 1 microM RA dose range, and maximal growth stimulation was observed in cells exposed to 1 nM of RA. Exposure of HGFs to 1 nM of RA resulted in an augmented cell cycle progression. To elucidate the molecular mechanisms underlying cell cycle regulation by RA, we measured the intracellular levels of major cell cycle regulatory proteins. The levels of cyclin E and cyclin-dependent kinase (CDK) 2 were found to be increased in HGFs following 1 nM of RA treatment. However, the levels of cyclin D, CDK 4, and CDK 6 were unchanged under these conditions. Also after exposure to 1 nM of RA, the protein levels of p21WAF1/CIP1 and p16INK4A were decreased in HGFs compared with the control group, but the levels of p53 and pRb were similar between treated and untreated cells. These results suggest that RA increases cell proliferation and cell cycle progression in HGFs via increased cellular levels of cyclin E and CDK 2, and decreased cellular levels of p21WAF1/CIP1 and p16INK4A.
Blotting, Western ; Cell Cycle ; Cell Cycle Proteins ; Cell Proliferation ; Cyclin D ; Cyclin E ; Cyclins ; Fibroblasts ; Flow Cytometry ; Humans ; Phosphotransferases ; Tretinoin

Anti-cancer drug resistance is a major problem in colorectal cancer (CRC) research. Although several studies have revealed the mechanism of cancer drug resistance, molecular targets for chemotherapeutic combinations remain elusive. To address this issue, we focused on the expression of cellular prion protein (PrPC) in 5-FU-resistant CRC cells. In 5-FU-resistant CRC cells, PrPC expression is significantly increased, compared with that in normal CRC cells. In the presence of 5-FU, PrPC increased CRC cell survival and proliferation by maintaining the activation of the PI3K-Akt signaling pathway and the expression of cell cycle-associated proteins, including cyclin E, CDK2, cyclin D1, and CDK4. In addition, PrPC inhibited the activation of the stress-associated proteins p38, JNK, and p53. Moreover, after treatment of 5-FU-resistant CRC cells with 5-FU, silencing of PrPC triggered apoptosis via the activation of caspase-3. These results indicate that PrPC plays a key role in CRC drug resistance. The novel strategy of combining chemotherapy with PrPC targeting may yield efficacious treatments of colorectal cancer.
Apoptosis ; Caspase 3 ; Cell Survival ; Colorectal Neoplasms* ; Cyclin D1 ; Cyclin E ; Cyclins ; Drug Resistance* ; Drug Therapy ; Fluorouracil ; Signal Transduction*

PURPOSE: Bile acids were considered as a promoting factor for colon cancers. It has been suggested that bile acids could promote cellular proliferation or apoptosis according to their concentration. Therefore, we studied the expression of cell cycle and apoptosis related proteins on HCT116 colon cancer cells according to different deoxycholic acid concentrations. METHODS: HCT116 colon cancer cells were incubated with low (20 micro M) and high (250 micro M) concentrations of deoxycholic acid for 72 hours. Cellular proliferation and toxicity were then measured by MTS assay. The expression of cell cycle and apoptosis related proteins was evaluated by Western blot analysis. RESULTS: In a low concentration of deoxycholic acid, the change of expression of the cell cycle related proteins-cyclin D1, cyclin E, cyclin A and CDK2 were similar compared with cultures that were without deoxycholic acid. In a high concentration of deoxycholic acid, cyclin A and cyclin D1 proteins were not expressed and the expression of cyclin E and CDK2 were decreased. The expression of survivin protein was increased by a low concentration of deoxycholic acid but it showed no significant difference when compared with cultures without deoxycholic acid. However in a high concentration of deoxycholic acid, survivin was not expressed. Deoxycholic acid has no effect on the expression of Bcl-2 and Bax proteins. CONCLUSION: A high concentration of deoxycholic acid can inhibit HCT116 colon cancer cell proliferation by suppressing the expression of all the cell cycle related proteins and also survivin, an inhibitor of apoptosis.
Apoptosis* ; bcl-2-Associated X Protein ; Bile Acids and Salts ; Blotting, Western ; Cell Cycle ; Cell Proliferation ; Colon* ; Colonic Neoplasms* ; Cyclin A ; Cyclin D1 ; Cyclin E ; Cyclins ; Deoxycholic Acid*