Abstract 3664: Bendamustine induces a dose-dependent cell cycle arrest in Hela cells that results in different mitotic outcomes

Author(s):  
Neil Beeharry ◽  
Corinne Stobbe ◽  
Mitchell R. Smith ◽  
Timothy J. Yen
2021 ◽  
Vol 11 ◽  
Author(s):  
Krishnambal Govender ◽  
Indres Moodley ◽  
Raveen Parboosing

Background: The aim of the study was to determine the mechanism of Moringa oleifera-induced apoptosis in HeLa cells. HeLa cells over-express cyclin E and cyclin B1, abrogate G0-G1 and G2-M cell cycle arrest, promoting tumorigenesis. Cyclin E, cyclin B1, E2F1 and telomerase expression, and caspase-3 and -7 activation were assessed after 24-treatment with M. oleifera leaf fractions. Material and methods: Apoptosis through caspase-3 and caspase-7 activation was determined quantitatively by the FAM FLICA™ Caspase-3/7 assay. Cyclin E, cyclin B1 and E2F1 were quantified by flow cytometry. Telomerase was evaluated by Telomeric repeat amplification protocol (TRAP reaction). The effects on colony formation were assessed by seeding treated cells in six-well plates for 7 days under culture conditions. The MTT assay was used to determine cell survival. Results: HeLa cells treated for 24 hours with M. oleifera leaf fractions showed dose-dependent cytotoxicity, activation of caspases-3 and -7; down-regulation of cyclin E, cyclin B1, E2F1, and inhibition of telomerase expression. Cell cycle analysis of the dead cell population showed G2-M cell-cycle arrest. Conclusion: M. oleifera leaf fractions triggered apoptosis through the mitochondrial pathway and cell cycle arrest at G2-M phase in HeLa cells after 24-hour treatment, through down-regulation of cyclin E and cyclin B1 expression; and caspase-3 and -7 activation. In addition, M. oleifera leaf extract induces senescence in HeLa cells through the down-regulation of telomerase. Colony formation and cell proliferation were inhibited in a dose-dependent manner, corresponding with telomerase inhibition.


2015 ◽  
Vol 10 (2) ◽  
pp. 409 ◽  
Author(s):  
Jing Lv ◽  
Ming-Qin Cao ◽  
Jian-Chun Yu

<p>The aim of the current study was to evaluate the anticancer and apoptotic effects of alantolactone pyrazoline analogue in human non-small cell lung cancer (NCI-H460) cells. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra-zolium bromide) assay was used to evaluate the cell viability while as fluorescence microscopy was used to assess the effect on apoptosis, cellular and nuclear morphology. Flow cytometry evaluated the effect of APA on cell cycle arrest in these cells. The results revealed that APA induced potent, time and dose-dependent cytotoxic effects on the growth of NCI-H460 cells. It also inhibited colony forming tendency as well as cell invasion capability of these cancer cells. APA induced dose-dependent nuclear and cellular morphological effects including chromatin condensation and DNA fragmentation. Flow cytometry revealed that the anticancer effects of APA might be due to its cell cycle arrest inducing tendency in G0/G1 phase of the cell cycle.</p>


2016 ◽  
Vol 11 (4) ◽  
pp. 838 ◽  
Author(s):  
Ning Xia

<p class="Abstract">The present study was aimed at to demonstrate the antitumor effects of syringin in HeLa human cervical cancer cells. Its effects on apoptosis, cell cycle phase distribution as well as on cell migration were also examined. The effect on cell proliferation was evaluated by MTT assay, while as effects on colony formation were assessed using clonogenic assay. Syringin inhibited cancer cell growth in HeLa cells in a time-dependent as well as in a concentration-dependent manner. Syringin also led to inhibition of colony formation efficacy with complete suppression at 100 µM drug dose. Syringin could induce G2/M cell cycle arrest along with slight sub-G1 cell cycle arrest. HeLa cells began to emit red fluorescence as the dose of syringin increased from 0 µM in vehicle control to 100 µM. Syringin also inhibited cell migration in a dose-dependent manner with 100 µM dose of syringin leading to 100% inhibition of cell migration.</p><p> </p>


2000 ◽  
Vol 20 (3) ◽  
pp. 1001-1007 ◽  
Author(s):  
Mark W. Jackson ◽  
Steven J. Berberich

ABSTRACT The p53 tumor suppressor protein is stabilized in response to cellular stress, resulting in activation of genes responsible for either cell cycle arrest or apoptosis. The cellular pathway for releasing normal cells from p53-dependent cell cycle arrest involves the Mdm2 protein. Recently, a p53-binding protein with homology to Mdm2 was identified and called MdmX. Like Mdm2, MdmX is able to bind p53 and inhibit p53 transactivation; however, the ability of MdmX to degrade p53 has yet to be examined. We report here that MdmX is capable of associating with p53 yet is unable to facilitate nuclear export or induce p53 degradation. In addition, expression of MdmX can reverse Mdm2-targeted degradation of p53 while maintaining suppression of p53 transactivation. Using a series of MdmX deletions, we have determined that there are two distinct domains of the MdmX protein that can stabilize p53 in the presence of Mdm2. One domain requires MdmX interaction with p53 and results in the retention of both proteins within the nucleus and repression of p53 transactivation. The second domain involves the MdmX ring finger and results in stabilization of p53 and an increase in p53 transactivation. The potential basis for stabilization and increased p53 transactivation by the MdmX ring finger domain is discussed. Based on these observations, we propose that the MdmX protein may function to maintain a nuclear pool of p53 protein in undamaged cells.


Cell Cycle ◽  
2005 ◽  
Vol 4 (3) ◽  
pp. 465-472 ◽  
Author(s):  
Stuart Gallagher ◽  
Richard F. Kefford ◽  
Helen Rizos

Sign in / Sign up

Export Citation Format

Share Document