Expression of viral oncoproteins results in the loss of cell cycle checkpoint control and the accumulation of chromosomal abnormalities. Expression of both human papillomavirus type 16 oncoproteins, E6 and E7, in normal human fibroblasts completely dissociates p21 and proliferating cell nuclear antigen from the quarternary cyclin-cyclin-dependent kinase (CDK) complexes present in normal cells, ...

The aim of our study was to determine to what degree one-year exposure of female rats to cadmium at a dose of 5, 50 and 100 mg Cd/l affects cell proliferation in the submandibular gland, shown by PCNA and Ki-67 expression. In the present study, we found a positive nuclear reaction for PCNA in single cells in microscopic preparations of control rats. In Group I, an increase was observed in the n...

The designed, chiral, acyclic polycarbamate nucleic acids (PCNA) exhibited sequence and orientation specific binding to nucleic acids. Complexes of PCNA with DNA were as stable as PNA:DNA complexes and those with RNA were as stable as natural DNA:RNA complexes.

The human papillomavirus type 18 E7 protein subverts the pRb/E2F pathway to promote S-phase reentry by postmitotic, differentiated primary human keratinocytes in support of viral DNA amplification. We prepared a panel of HPV-18 E7 mutations in pRb binding or in casein kinase II (CKII) phosphorylation. Our results showed that the ability of E7 binding to pRb correlated with the activation of DNA...

Chromatin endowed by histone modifications governs chromatin structure, which in turn represents a means to regulate cellular processes, including transcription and heterochromatin formation. Recent evidence revealed a plethora of enzymes that catalyze specific histone modifications for epigenetic maintenance, and dysregulation of which contributes to tumorigenesis and developmental defects. Th...

The requirement of a metalloprotease, a disintegrin and metalloprotease 17 (ADAM17) for the growth of cultured vascular smooth muscle cells has been demonstrated in vitro. However, whether this metalloprotease is responsible for vascular remodeling in vivo remains unanswered. Rat carotid arteries were analyzed 2 weeks after a balloon angioplasty. The neointimal cells were strongly positive for ...

Epithelial cell proliferation was studied in the normal colonic mucosa of 5-week-old Sprague-Dawley rats, comparing [3H]thymidine incorporation (group 1) with two newer proliferation markers, bromodeoxyuridine (group 2) and proliferating cell nuclear antigen (group 3). Microautoradiography (group 1) or immunoperoxidase assays (groups 2 and 3) were carried out. Cells were counted for positive re...

The structure and connectivity of protein-protein interaction (PPI) networks are maintained throughout evolution by coordinated changes (coevolution) of network proteins. Despite extensive research, relatively little is known regarding the molecular basis and functional implications of the coevolution of PPI networks. Here, we used proliferating cell nuclear antigen, a hub protein that mediates...