The changes in the cell cycle distribution are associated with changed expression levels of CDKN1B (p27Kip1), a general inhibitor of Cyclin-CDK complexes and, thereby, of cell cycle progression.
However, no significant changes in the cell cycle patterns were observed between untransfected and Sin3B transfected cells under normal cycling conditions/without drug treatment.
This instability may be related to changes in the cell cycle and extracellular matrix degradation.
(c) Changes in the cell cycle markers Ccnd1a (Cyclin D1) and Cdkn1a (p21) were assessed by RT-qPCR, and (d) CCND1A by western blot.
Computations with an experimentally parameterized mathematical model show that modest changes in the Wee1/Cdc25 ratio can account for the observed qualitative changes in the cell cycle.
In addition, the modest level of MYC overexpression did not cause major changes in the cell cycle profile or timing of cell division in IMEC-MYC (Supplementary Fig. 1d, e).
Finally, changes in the cell cycle of the involved epithelium, with an increased number of cells in the S phase (corresponding to DNA synthesis) and the G2 phase (premitosis), have been described.70 Currently, the changes suggested to be of potential help in the surveillance of patients include changes in DNA content (DNA aneuploidy), increased proliferation, and alterations of p53.
In addition, knockdown of MELK with siRNA decreased cell proliferation and caused changes in the cell cycle after radiation or 5-FU treatment.
Regarding the mechanistic aspects of the above cytotoxic activity, flow cytometric analysis of DNA content did not reveal significant changes in the cell cycle phase distribution of rhodanine-treated HT-1080 comparedmpared with control ones, with the exception of an S-phase arrest caused by compounds 43 and 45 at 48 h (not shown).
No changes in the cell cycle profile (as analyzed by FACS) were detected in these experiments (data not shown).
In contrast, there were no significant changes in the cell cycle profile of differentiated ES cells after BNP knockdown (Fig. 4C).
