Although PTEN/Akt signaling is frequently deregulated in human gastric cancers, the in vivo causal link between its dysregulation and gastric tumorigenesis has not been established. Here we show that inactivation of PTEN in mouse gastric epithelium initiates spontaneous carcinogenesis with complete penetrance by 2 months of age. Mechanistically, activation of Akt suppresses the abundance of p53...

The bovine papillomavirus E2 protein can inhibit the proliferation of HT-3 cells, a p53-negative cervical carcinoma cell line containing integrated human papillomavirus type 30 DNA. Here, we analyzed HT-3 cells to explore the mechanism of p53-independent E2-mediated growth inhibition. Expression of the E2 protein repressed expression of the endogenous human papillomavirus type 30 E6/E7 genes. T...

Caulibugulones are novel but poorly characterized cytotoxic isoquinoline quinones and iminoquinones identified in extracts from the marine bryozoan Caulibugula intermis. We now report that the caulibugulones are selective in vitro inhibitors of the Cdc25 family of cell cycle-controlling protein phosphatases compared with either human vaccinia H1-related phosphatase (VHR) or tyrosine phosphatase...

This paper proposes a model in terms of metabolic P graphs of a few important processes occurring during the biological phase where the choice is made to begin again mitosis or to arrest it. The cellular processes during this phase turn out to be especially interesting in the case of DNA damage, which triggers a specific destruction of Cdc25A phosphatase. It has important implications to unders...

Emerging evidences show that disruption of the circadian rhythm is associated with tumor initiation and progression. Neuronal PAS domain protein 2 (NPAS2), one of the core circadian molecules, has been proved to be a potential prognostic biomarker in colorectal and breast cancers. However, to date, the potential functional roles and molecular mechanisms by which NPAS2 affects cancer cell surviv...

The Cdc25 family of protein phosphatases positively regulates cell division by activating cyclin-dependent protein kinases (CDKs). In humans and rodents, there are three Cdc25 family members--denoted Cdc25A, Cdc25B, and Cdc25C--that can be distinguished based on their subcellular compartmentalizations, their abundances and/or activities throughout the cell cycle, the CDKs that they target for a...

In this study, experimental pathology, flow cytometry (FCM), quantitative real-time polymerase chain reaction (qRT-PCR), and western blot (WB) were used to evaluate the effects of sodium fluoride (NaF) on hepatocellular cell cycle progression in mice. A total of 240 ICR mice were divided equally into four groups; the experimental groups received 12, 24, or 48 mg/kg NaF intragastrically for 42 d...

The cell division cycle 25 (CDC25) phosphatases include CDC25A, CDC25B and CDC25C. These three molecules are important regulators of several steps in the cell cycle, including the activation of various cyclin-dependent kinases (CDKs). CDC25s seem to have a role in the development of several human malignancies, including acute myeloid leukemia (AML); and CDC25 inhibition is therefore considered ...

Nitroxoline is an antibiotic by chelating Zn2+ and Fe2+ from biofilm matrix. In this study, nitroxoline induced G1 arrest of cell cycle and subsequent apoptosis in prostate cancer cells through ion chelating-independent pathway. It decreased protein levels of cyclin D1, Cdc25A and phosphorylated Rb, but activated AMP-activated protein kinase (AMPK), a cellular energy sensor and signal transduce...