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

PURPOSE: Peroxisome proliferator-activated receptor gamma (PPARgamma) has become a potential target for the prevention and treatment of human cancers. PPARgamma ligands inhibit cell proliferation of estrogen receptoralpha(ERalpha)-positive breast cancer cells. However, it has recently been shown that ERalpha-negatively inhibits PPARgamma signaling in breast cancer cells, indicating that PPARgamma ligand may be more useful for treating ERalpha-negative breast cancer cells compared to ERalpha-positive breast cancer cells. In this study, we attempted to elucidate the role of PPARg in ERalpha-negative breast cancer cells. METHODS: The effect of PPARgamma ligand on the growth of MDA-MB-231 cells was measured by MTT assay and flow cytometric analysis. TUNEL staining and Hoechst 33342 fluorescent staining were used to observe the effects of PPARgamma ligand on cell apoptosis. The regulatory proteins of the cell cycle were measured by Western blot. RESULTS: The treatment of MDA-MB-231 human breast cancer cells with the PPARgamma ligand, trgoglitazone, was shown to induce inhibition of cell growth in a dose-dependent manner. Cell cycle analysis showed a G1 arrest in MDA-MB-231 cells exposed to troglitazone. The apoptotic effect by troglitazone demonstrated that apoptotic cells were elevated from 2.5-fold of the control level at 10 mM, to 3.1-fold at 50micrometer and to 3.5-fold at 75 mM of troglitazone. Moreover, troglitazone treatment dose-dependently caused a marked decrease in the pRb, cyclin D1, cyclin D2, cyclin D3, cdk2, Cdk4 and Cdk6 expressions and there was a significant increase in the p21 and p27 expressions. CONCLUSION: These results indicate that trgoglitazone induces cell-cycle G1 arrest and apoptosis in ERalpha-negative MDA-MB-231 breast cancer cells. Collectively, this paper shows that PPARgamma ligand is an important player as a member of the chemotherapeutic candidates for treating ERalpha-negative breast cancer.
Apoptosis* ; Blotting, Western ; Breast Neoplasms* ; Breast* ; Cell Cycle ; Cell Proliferation ; Cyclin D1 ; Cyclin D2 ; Cyclin D3 ; Estrogens ; Humans ; In Situ Nick-End Labeling ; Ligands ; Peroxisomes* ; PPAR gamma*

The molecular mechanisms that regulate glossal muscle cell cycle and terminal differentiation remain largely unknown. To determine which cyclins, cyclin dependent kinases (CDKs), cyclin dependent kinase inhibitors (CKIs) are important for glossal cell proliferation, we have examined expression of cyclins CDKs, CKIs during normal glossal muscle development in the rat. All cyclins, CDKs, and KIP/CIP family of CKIs were highly expressed during fetal glossal muscle development, then they decreased at different rates after birth. While the mRNAs of cyclin Dl, D3, E , A, and B decreased gradually in glossal muscle during all stages of development, the protein levels of these cyclins decreased differently in tongue during pre- and postnatal development. While the functionally active formed of cyclin Dl, cyclin D3 and E proteins were observed until 7 days after birth, cyclin A and B proteins were decreased more slowly. While the CDK4, CDK6, CDK2, cdc2, and proliferating cell nuclear antigen (PCNA) proteins were higllly present during fetal glossal muscle development and gradually decreased during postnatal development. Particularly, cdc2 levels decreased markedly after birth. Immunohistochemical data for PCNA was consistent with Western blotting data for PCNA temporally and spatially. The mRNA and protein levels of p21, p27, and p57 were high, then their levels changed differently during glossal development. While the mRNA levels of p21 and p57 decreased gradually, the mRNA level of p27 did not change during glossal development. While the protein levels of p21 and p57 in tongue decreased markedly after birth, the protein levels of p27 increased slightly after birth, then decreased at adulthood. These findings suggest that the all cyclins and CDKs observed are involved in glossal muscle cell cycle, and reduction of cyclins and CDKs and induction of p21 are associated with the withdrawal of glossal muscle cell cycle after birth.
Animals ; Blotting, Western ; Cell Proliferation ; Cyclin A ; Cyclin D3 ; Cyclin-Dependent Kinases* ; Cyclins* ; Humans ; Muscle Cells ; Muscle Development ; Parturition ; Phosphotransferases* ; Proliferating Cell Nuclear Antigen ; Rats* ; RNA, Messenger ; Tongue

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

OBJECTIVETo investigate the expression, localization and interrelationship of P27(kip1) and cyclin D3 in non-Hodgkin's lymphoma (NHL).

METHODSThe expressions of P27(kip1), cyclin D3 and index Ki-67 was detected in 100 NHL and 20 reactive lymph nodes by immunohistochemical technique. The expression and localization of P27(kip1) and cyclin D3 in 3 NHL cell lines were detected by Western blot, double immunolabelling and laser scanning confocal microscopy, respectively.

RESULTSIn general the expression of P27(kip1) in NHL was lower than in control group, and was negatively related to the tumor aggressiveness and proliferating activity; the expression of cyclin D3 in NHL was higher than in control group, and was positively related to the tumor aggressiveness and proliferating activity. There was a negative correlation between P27(kip1) and cyclin D3. Nevertheless, anomalous high P27(kip1) expression was found in a few NHL tissues with high expression of cyclin D3 and Ki-67. Overexpression and colocalization of P27(kip1) and cyclin D3 was found in Raji cell line.

CONCLUSIONSUnder expression of P27(kip1) and overexpression of cyclin D3 may play a role in the occurrence and development of NHL. Anomalous high P27(kip1) expression and its interaction with cyclin D3 may be another mechanism for tumor genesis of NHL.

Cell Line, Tumor ; Cyclin D3 ; Cyclin-Dependent Kinase Inhibitor p27 ; genetics ; metabolism ; Cyclins ; genetics ; metabolism ; Humans ; Lymphoma, Non-Hodgkin ; genetics ; metabolism ; pathology

Eugenol is an essential oil found in cloves and cinnamon that is used widely in perfumes. However, the significant anesthetic and sedative effects of this compound have led to its use also in dental procedures. Recently, it was reported that eugenol induces apoptosis in several cancer cell types but the mechanism underlying this effect has remained unknown. In our current study, we examined whether the cytotoxic effects of eugenol upon human melanoma G361 cells are associated with cell cycle arrest and apoptosis using a range of methods including an XTT assay, Hoechst staining, immunocytochemistry, western blotting and flow cytometry. Eugenol treatment was found to decrease the viability of the G361 cells in both a time- and dose-dependent manner. The induction of apoptosis in eugenol-treated G361 cells was confirmed by the appearance of nuclear condensation, the release of both cytochrome c and AIF into the cytosol, the cleavage of PARP and DFF45, and the downregulation of procaspase-3 and -9. With regard to cell cycle arrest, a time-dependent decrease in cyclin A, cyclin D3, cyclin E, cdk2, cdk4, and cdc2 expression was observed in the cells after eugenol treatment. Flow cytometry using a FACScan further demonstrated that eugenol induces a cell cycle arrest at S phase. Our results thus suggest that the inhibition of G361 cell proliferation by eugenol is the result of an apoptotic response and an S phase arrest that is linked to the decreased expression of key cell cycle-related molecules.
Apoptosis ; Blotting, Western ; Caspase 3 ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Proliferation ; Cinnamomum zeylanicum ; Cyclin A ; Cyclin D3 ; Cyclin E ; Cyclins ; Cytochromes c ; Cytosol ; Down-Regulation ; Eugenol ; Flow Cytometry ; Humans ; Hypnotics and Sedatives ; Immunohistochemistry ; Melanoma ; S Phase ; Syzygium

BACKGROUND: Chemotherapy with 5-fluorouracil (5-FU) has been one of the mainstay in breast cancer treatment. The effects of high dose 5-FU on cell cycle regulation were studied in breast caner cells. METHODS: A breast cancer cell line MCF-7 was used. Protein expressions of G1/S cyclins, p21(Waf1/Cip1), cdk2, E2F1 and retinoblastoma were tested by western blot analysis. Immunoprecipitation and immune complex kinase assay were done for the assessment of E2F1/RB interacton and the activity of cdk2 respectively. RESULTS: p21(Waf1/Cip1) expression was barely detectable in control cells. With addition of 5-FU level of p21(Waf1/Cip1) were induced and cyclin D3 level was decreased as cell growth decreases. In accordance with increased expression of p21(Waf1/Cip1), cyclin E-associated cdk2 kinase activity was reduced. Retinoblastoma protein (RB) became dephosphorylated and E2F-1 binding activity with RB was increased. CONCLUSION: In this situation of high concentration of 5-FU breast cancer cells tend to be G1/S cell cycle arrested. Overexpression of p21(Waf1/Cip1) and dephosphorylation of RB may mediate the effectss of 5-FU by inhibiting E2F-1 activity, which contributes to G1/S cell cycle arrest. These results could be an indicating landmark for further study of high dose chemotherapy with 5-FU.
Antigen-Antibody Complex ; Blotting, Western ; Breast Neoplasms* ; Breast* ; Cell Cycle Checkpoints ; Cell Cycle* ; Cell Line* ; Cyclin D3 ; Cyclins ; Drug Therapy ; Fluorouracil* ; Immunoprecipitation ; Phosphotransferases ; Retinoblastoma ; Retinoblastoma Protein

The anti-cancer effects of betulinic acid (BA) on Jurkat cells and its in vitro mechanism were examined by using MTT assay. Apoptosis was detected by using Hoechst33258 staining and annexin-V/PI double-labeled cytometry. The effects of betulinic acid on the cell cycle of Jurkat cells were studied by propidium iodide method. RT-PCR and Western blotting were used to analyze the changes of cyclin D3, bcl-xl mRNA and protein levels in Jurkat cells after treatment with betulinic acid. Our results showed the proliferation of Jurkat cells was decreased in betulinic acid-treated group with a 24-h IC50 value being 70.00 mumol/L. Betulinic acid induced apoptosis of Jurkat cells in a time- and dose-dependent manner. The number of Jurkat cells treated with betulinic acid showed an increase in G(0)/G(1) phase and decrease in S phase. After treatment with 0, 20, 60, 100 mumol/L betulinic acid for 24 h, the number of Jurkat cells was increased from (31.00+/-1.25)% to (58.84+/-0.32)% in G(0)/G(1) phase, whereas it was decreased from (61.45+/-1.04)% to (35.82+/-1.95)% in S phase. PBMCs were less sensitive to the cytotoxicity of betulinic acid than Jurkat cells. The expressions of cyclin D3, bcl-xl mRNA and protein were decreased sharply in Jurkat cells treated with betulinic acid. It is concluded that betulinic acid is able to inhibit the proliferation of Jurkat cells by regulating the cell cycle, arrest cells at G(0)/G(1) phase and induce the cell apoptosis. The anti-tumor effects of betulinic acid are related to the down-regulated expression of cyclin D3 and bcl-xl.
Antineoplastic Agents, Phytogenic/*pharmacology ; Apoptosis/*drug effects ; Cell Proliferation/*drug effects ; Cyclin D3/metabolism ; Down-Regulation/drug effects ; Jurkat Cells ; Triterpenes/*pharmacology ; bcl-X Protein/metabolism

OBJECTIVETo clarify the role of these cyclins in human gastric cancer.

METHODS38 gastric cancer patients, 29 first degree relatives of gastric cancer patients, as well as 18 healthy subjects were included. The mRNA expression of cyclins D1, D2, D3 and E in gastric biopsies was evaluated by RT-PCR analysis using specific primers. Histomorphological features such as intestinal metaplasia, atrophy, H. pylori infection and severity of gastritis were determined by the updated Sydney System.

RESULTSSignificant mRNA overexpression was found for cyclins D2, D3 and E compared with healthy normal specimen, but cyclin D1 expression was not different between tumor and normal tissues. In addition, cyclin D2 and D3 overexpression was significantly more frequent in first degree relatives than in healthy controls (P < 0.05). Among the various pathological findings, the overexpression of cyclins D2 and E was associated with intestinal metaplasia, and the overexpression of cyclin D3 was associated with intestinal metaplasia as well as atrophy. The overexpression of cyclins D2 and D3 was significantly correlated with H. pylori infection. No correlation was observed between the overexpression of cyclin D1 and any pathological variables.

CONCLUSIONThe overexpression of cyclins D2, D3 and E is a frequent event in patients with gastric cancer and their first degree relatives and may be an early event in gastric carcinogenesis.

Adult ; Aged ; Aged, 80 and over ; Cyclin D1 ; genetics ; Cyclin D2 ; Cyclin D3 ; Cyclin E ; genetics ; Cyclins ; genetics ; Family Health ; Gastritis ; genetics ; Gene Expression Regulation, Neoplastic ; Helicobacter Infections ; genetics ; microbiology ; Helicobacter pylori ; growth & development ; Humans ; Middle Aged ; RNA, Messenger ; genetics ; metabolism ; Stomach ; metabolism ; microbiology ; pathology ; Stomach Neoplasms ; genetics ; pathology

Long-term spaceflight affects numerous organ systems in the body, including metabolic dysfunction. Recently, ample evidence has demonstrated that the liver is a vulnerable organ during spaceflight. However, the changes in hepatocyte proliferation and cell cycle control under microgravity remain largely unexplored. In the present study, we first confirmed that the serum levels of aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase, biochemical markers of liver function, were altered in rats under tail suspension (TS) conditions to simulate microgravity, as shown in previous reports. Next, we demonstrated that the cell proliferation activity, determined by Ki67, PCNA and PH3, was significantly decreased at the different TS time points (TS for 14, 28 and 42 days) compared with that in the control group. Consistently, the positive cell cycle regulators Ccna2, Ccnd1, Cdk1, Cdk2 and cyclin D3 were also significantly decreased in the TS groups as shown by quantitative real-time PCR and western blotting analysis. Subsequent analysis revealed that the aberrant hepatocyte proliferation inhibition under simulated microgravity was associated with the upregulation of miR-223 in the liver. We further found that miR-223 inhibited the proliferation of Hepa1-6 cells and identified CDK2 and CUL1 as its direct targets. In addition, the decreased expression of CDK2 and CUL1 was negatively correlated with the level of p27 in vitro and in vivo, which may have been responsible for retarding hepatocyte proliferation. Collectively, these data indicate that upregulation of miR-223 was associated with the inhibition of liver cell growth and reveal the role of miR-223 in rat hepatocyte proliferation disorders and the pathophysiological process under simulated microgravity.
Alanine Transaminase ; Alkaline Phosphatase ; Animals ; Aspartate Aminotransferases ; Biomarkers ; Blotting, Western ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Proliferation ; Cyclin D3 ; Hepatocytes* ; Hindlimb Suspension ; In Vitro Techniques ; Liver* ; Proliferating Cell Nuclear Antigen ; Rats* ; Real-Time Polymerase Chain Reaction ; Space Flight ; Up-Regulation* ; Weightlessness*