Cyclin D1 regulates mitogen-dependent progression through G(1) phase in cultured cells, and its overexpression in malignant cells is thought to contribute to autonomous proliferation in vivo. However, previous studies in cell lines have not demonstrated that cyclin D1 is sufficient to trigger cell replication. In this study, we found that transient transfection of adult hepatocytes with cyclin ...

Cyclin D1 regulates cell proliferation and is a candidate molecular target for breast cancer therapy. This study addresses whether Cyclin D1 is indispensable for ErbB2-associated mammary tumor initiation and progression using a breast cancer model in which this cell-cycle regulator can be genetically ablated prior to or after neoplastic transformation. Deficiency in Cyclin D1 delayed tumor onse...

Cyclin D1, an important cell cycle regulator, is overexpressed in several human cancers including breast. Both estrogens and progestins activate the transcription of the gene; antiestrogens have been shown to reduce cyclin D1 protein levels. Cyclin D1 protein overexpression has been strongly associated with well-differentiated, estrogen receptor-positive tumors. Little is known, however, as to ...

PURPOSE Despite promising initial results, recent Phase III trials of the selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor gefitinib ("Iressa"; AstraZeneca, Wilmington, Delaware) in advanced head and neck squamous cell carcinoma (HNSCC) have been equivocal. Cyclin D1, an EGFR target gene, is frequently overexpressed in HNSCC, has been implicated in its pathogenesis, a...

AIMS Several studies have reported that dysregulation of beta catenin or k-ras mutation promotes cyclin D1 expression. This study investigated the relation between cyclin D1 expression and clinicopathological parameters in carcinoma of the ampulla of Vater (CAV), and also assessed the relation between increased cyclin D1 expression and beta catenin/k-ras status in this series. METHODS Thirty ...

Cyclin D1 controls G1-associated processes, including G0-to-G1 and G1-to-S transitions. This study demonstrates a novel aspect of cyclin D1 as a regulator of the transition between G1 and G0. Overexpression of cyclin D1 in MCF7 breast tumor cells resulted in a continued proliferation under low-serum conditions, whereas nonoverexpressing cells ceased to grow. This difference in growth was due to...

Our previous studies indicate that the activation of mitogenactivated protein kinase (MAPK) pathway is involved in bombesin-induced cell proliferation in prostate cancer cells. Cyclin D1 is a critical regulator involved in cell cycle progression through the G1 phase into the S phase, thereby contributing to cell proliferation. Mostly, mitogen-stimulated expression of cyclin D1 is attributed to ...

The retinoids are reported to reduce incidence of second primary aerodigestive cancers. Mechanisms for this chemoprevention are previously linked to all-trans retinoic acid (RA) signaling growth inhibition at G1 in carcinogen-exposed immortalized human bronchial epithelial cells. This study investigated how RA suppresses human bronchial epithelial cell growth at the G1-S cell cycle transition. ...

Cyclin D1, an important cell cycle regulator, is overexpressed in several human cancers including breast. Both estrogens and progestins activate the transcription of the gene; antiestrogens have been shown to reduce cyclin D1 protein levels. Cyclin D1 protein overexpression has been strongly associated with well-differentiated, estrogen receptor-positive tumors. Little is known, however, as to ...

Prognostic markers for colorectal cancer (CRC) have not yet been fully investigated. Phosphatase and tensin homolog (PTEN), p27 and Cyclin D1 play significant roles in tumorigenesis and cell cycle regulation, and therefore require evaluation for their prognostic value in this disease. The aim of the present study was to assess the prognostic value of the single and combined expression of PTEN, ...