Stem cells can reside in a state of reversible growth arrest, or quiescence, for prolonged
periods of time. Although quiescence has long been viewed as a dormant, low-activity state …

Uncontrolled cell proliferation is the hallmark of cancer, and tumor cells have typically
acquired damage to genes that directly regulate their cell cycles. Genetic alterations …

Senescence refers to a cellular state featuring a stable cell‐cycle arrest triggered in
response to stress. This response also involves other distinct morphological and intracellular …

Aberrant function of cell cycle regulators results in uncontrolled cell proliferation, making
them attractive therapeutic targets in cancer treatment. Indeed, survival of many cancers …

First identified as cell cycle inhibitors mediating the growth inhibitory cues of upstream
signaling pathways, the cyclin-CDK inhibitors of the Cip/Kip family p21Cip1, p27Kip1, and …

The irreversible G1 arrest in senescent human diploid fibroblasts is probably caused by
inactivation of the G1cyclin–cyclin-dependent kinase (Cdk) complexes responsible for …

IGF-I receptor (IGF-IR) signaling and functions are mediated through the activities of a
complex molecular network of positive (eg., type I IGF) and negative (eg., the type II IGF …

Targeted disruption of the murine p27 Kip1 gene caused a gene dose–dependent increase
in animal size without other gross morphologic abnormalities. All tissues were enlarged and …

Autophagy is a self-degradation pathway, in which cytoplasmic material is sequestered in
double-membrane vesicles and delivered to the lysosome for degradation. Under basal …

Disruption of the cyclin-dependent kinase–inhibitory domain of p27 enhances growth of
mice. Growth is attributed to an increase in cell number, due to increased cell proliferation …