Cyclin D1 is widely believed to regulate progression through G1 phase of the cell cycle, and previous studies have shown that this protein is induced during hepatocyte proliferation in culture and in vivo. In this study, the role of cyclin D1 in the cell cycle of primary rat hepatocytes was further examined. Following epidermal growth factor stimulation, cyclin D1 was upregulated at time points...

Cyclin D1 is a key cell cycle regulatory protein with demonstrated oncogenic activity in a variety of malignancies. Cyclin D1 mRNA and protein are overexpressed in approximately 50% of primary breast carcinomas; however, the pathophysiological consequences of increased expression remain unclear. To investigate the functional sequelae of cyclin D1 mRNA overexpression, we analyzed clinical outcom...

Cyclin D1 regulates G1 progression. Its transcriptional regulation is well understood. However, the mechanism underlying cyclin D1 ubiquitination and its subsequent degradation is not yet clear. We report that cyclin D1 undergoes increased degradation in the cytoplasm during S phase in a variety of cancer cells. This is mediated by phosphorylation at Thr286 through the activity of the Ras/Raf/M...

Although the molecular changes that characterize gliomas have been studied, the pathogenesis of tumor development remains unclear. p21 contributes to gliomagenesis by stabilizing cyclin D1-cdk4 kinase complexes, suggesting that cyclin D1 and cdk4 may also be required for glial tumor development. In this study, we used a mouse model to attempt to confirm this hypothesis, finding that cyclin D1 a...

Cyclin D1 is one of the most commonly overexpressed oncogenes in breast cancer; yet, it is not clear whether cyclin D1 alone is capable of causing malignant transformation of mammary epithelial cells. Here, we show that ectopic expression of cyclin D1 in benign mouse mammary epithelial cells promotes cell proliferation, anchorage-independent growth in soft agar, and tumorigenesis in severe comb...

Transforming growth factor-beta1 (TGF-beta1) inhibits cell growth in susceptible cells by interacting with a family of protein kinases that control cell cycle progression. In the present study, we investigated the effects of TGF-beta1 on cyclin D1 expression and activity in COLO-357 human pancreatic cancer cells. TGF-beta1 increased cyclin D1 mRNA and protein levels. Nuclear runoff transcriptio...

The t(11;14)(q13;q32) is the most common translocation in multiple myeloma (MM), resulting in up-regulation of cyclin D1. We used a segregation fluorescence in situ hybridization (FISH) assay to detect t(11;14) breakpoints in primary MM cases and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) to quantify cyclin D1 and MYEOV (myeloma overexpressed) expression, another putativ...

BACKGROUND Psoralea Fructus (PF), the dried and ripe fruit of Psoralea corylifolia exhibits an anti-cancer activity. However, the molecular mechanisms by which PF inhibits the proliferation of cancer cells have not been elucidated in detail. Cyclin D1 and CDK4 are important regulatory proteins in cell growth and are overexpressed in many cancer cells. In this study, we investigated the molecula...

Colorectal cancer is the third most common cancer worldwide. Aberrant overexpression of antiapoptotic BCL-2 (B-cell lymphoma 2) family proteins is closely linked to tumorigenesis and poor prognosis in colorectal cancer. Obatoclax is an inhibitor targeting all antiapoptotic BCL-2 proteins. A previous study has described the antiproliferative action of obatoclax in one human colorectal cancer cel...

OBJECTIVE To explore the expression of A-kinase anchor protein 95 (AKAP95), Cyclin D1, Cyclin E1, and Connexin43 (Cx43) in rectal cancer tissues and assess the associations between each of the proteins and pathological parameters, as well as their inter-relationships. METHODS AKAP95, Cyclin D1, Cyclin E1, and Cx43 protein expression rates were evaluated by immunohistochemistry in 50 rectal ca...