Library Subscription: Guest
Begell Digital Portal Begell Digital Library eBooks Journals References & Proceedings Research Collections
Journal of Environmental Pathology, Toxicology and Oncology
IF: 1.625 5-Year IF: 1.63 SJR: 0.402 SNIP: 0.613 CiteScore™: 2.3

ISSN Print: 0731-8898
ISSN Online: 2162-6537

Journal of Environmental Pathology, Toxicology and Oncology

DOI: 10.1615/JEnvironPatholToxicolOncol.v20.i3.20
12 pages

Abrogation of Cell Cycle Checkpoint Controls During Malignant Transformation of Syrian Hamster Embryo Cells is Associated with Decreased Sensitivity to Apoptosis

K. V. K. Rao
Cellular Carcinogenesis Laboratory, Cancer Research Institute, Tata Memorial Centre, Parel, Mumbai 400012, India
Daisy M. Mahudawala
Cellular Carcinogenesis Laboratory, Cancer Research Institute, Tata Memorial Centre, Parel, Mumbai 400012, India
Alka A. Redkar
Tumour Marker Laboratory, Tata Memorial Hospital, Tata Memorial Centre, Parel, Mumbai, India

ABSTRACT

Malachite green (MG), consisting of green crystals with a metallic luster, is highly soluble in water, cytotoxic to various mammalian cells, and may act as a liver tumor promoter. In view of its industrial importance and possible exposure to human beings, MG poses a potential environmental health hazard. We have reported earlier the malignant transformation of Syrian hamster embryo (SHE) cells by MG. In this study, we investigated the effects of MG on flow cytometric cell cycle phase distribution of normal and MG-transformed SHE cells in asynchronous and synchronous cell populations. DNA flow cytometric analysis indicated that culturing cells for 48 hours in a medium containing MG 0.1 [mg/mL induced G2/M arrest in normal cells. Malignant-transformed cells showed no such accumulation of cells at the G2/M phase of the cell cycle in response to MG. Synchronization studies indicated that in the control, both in the presence and absence of MG, cells followed a normal cell cycle pattern up to 16 hours. After 16 hours, in the absence of MG, cells continued a normal cell cycle, whereas in the presence of MG they accumulated at the G2/M phase of the cell cycle. This pattern of accumulation of cells at the G2/M checkpoint control was not observed in either untreated or MG-treated transformed cells. We also studied the effects of MG on the induction of apoptosis using flow cytometric FSC/SSC scatter plots in normal and transformed SHE cells. Flow cytometric analysis showed a dose- and time-dependent induction of apoptosis by MG in control cells, whereas induction of apoptosis by MG was marginal in transformed cells. In the present study, we demonstrated the efficient operation of the G2/M checkpoint control, apoptosis in control SHE cells, the abrogation of checkpoint controls, and decreased sensitivity to apoptosis in transformed SHE cells.


Articles with similar content:

Molecular Characterization of Isocyanate-Induced Male Germ-Line Genomic Instability
Journal of Environmental Pathology, Toxicology and Oncology, Vol.29, 2010, issue 3
Deepika Jain, Gorantla Venkata Raghuram, Smita Banerjee, Subodh Kumar Jain, Hariom Panwar, Pradyumna Kumar Mishra, Neelam Pathak, Hemant Pandey
Vanadate Induces G2/M Phase Arrest in p53-Deficient Mouse Embryo Fibroblasts
Journal of Environmental Pathology, Toxicology and Oncology, Vol.21, 2002, issue 3
Fei Chen, Zhuo Zhang, Chuanshu Huang, Xianglin Shi
Cell Cycle Regulators Modulating Con A Mitogenesis and Apoptosis in Low-Dose Radiation-Exposed Mice
Journal of Environmental Pathology, Toxicology and Oncology, Vol.24, 2005, issue 1
Krishna B. Sainis, Bhavani Shankar
Wnt Pathway in Pulmonary Fibrosis in the Bleomycin Mouse Model
Journal of Environmental Pathology, Toxicology and Oncology, Vol.28, 2009, issue 2
William N. Rom, Ting-An Yie, Herman T. Yee, Li Liu, Benjamin Carron, Mustapha Hajjou
Curcumin Modulates Hepatocellular Carcinoma by Reducing UNC119 Expression
Journal of Environmental Pathology, Toxicology and Oncology, Vol.38, 2019, issue 3
Wu Yuan Seng, Anshoo Malhotra, Zhenjiang Zhao