Computerized Video Time-Lapse Microscopy Studies of Ionizing Radiation-Induced Rapid-Interphase and Mitosis-Related Apoptosis in Lymphoid Cells

Abstract

Computerized video time-lapse (CVTL) microscopy of X-irradiated cultures of cells of the murine lymphoma cell lines ST4 and L5178Y-S and the human lymphoid cell line MOLT-4 demonstrated that these cells exhibit a wide disparity in the timing of induction and execution of radiation-induced cell death that included rapid-interphase apoptosis, delayed apoptosis, and postmitotic apoptosis. ST4 cells that received 2.5 or 4 Gy of X radiation underwent rapid-interphase apoptosis within 2 h. Apoptosis commenced with a 10-20-min burst of membrane blebbing followed by swelling for 2-4 h and cell collapse. No apoptotic bodies were formed. After a dose of 1 Gy, approximately 90% of ST4 cells died by rapid-interphase apoptosis, while the remainder completed several rounds of cell division prior to cell death. Postmitotic death of ST4 cells occurred with the same morphological sequence of events as during rapid-interphase apoptosis induced by doses of 1-4 Gy. In contrast, L5178Y-S and MOLT-4 cells that received 4 Gy underwent apoptosis more slowly, with a complex series of events occurring over 30-60 h. Only 3% of L5178Y-S cells and 24% of MOLT-4 cells underwent apoptosis without attempting cell division. The cells became abnormally large during a long G(2)-phase delay, and then most of the cells (76-97%) attempted to divide for the first or second time at approximately 18-30 h postirradiation. However, either mitosis failed or division was aberrant; i.e., the large cells divided into three or four fragments which eventually fused together. This process was followed by several rounds of complex and unpredictable membrane blebbing, gross distortions of shape, fragmentation-refusion events, and formation of apoptotic bodies, after which the cells collapsed at 36-60 h postirradiation.

Disruption of Cancer Cell Replication by Alternating Electric Fields

“…During this process, the cell membrane ruptured, and many small membrane blebs formed, resembling post-mitotic apoptotic cell death (13). Two exemplary cells undergoing such destruction are shown in Fig.…”

New concepts in radiation‐induced apoptosis: ‘premitotic apoptosis’ and ‘postmitotic apoptosis’

“…Recently, Endlich et al performed a more precise morphological analysis to further define the modes of radiation-induced cell death by using a computerized video time-lapse (CVTL) microscopy [12]. The CVTL technique allows the investigator to record the precise relationship between cell death and other observable events in individual cells [13,14].…”

“…In contrast, Tauchi and Sawada [17] characterized radiationinduced death of L5178Y cells as apoptosis after mitotic failure. Endlich et al [12] verified the induction of apoptosis after irradiation of ST4, L5178Y-S and MOLT-4 cells by visualizing apoptosis with a Hoechst 33324/PI staining. According to their report, early apoptosis occurred at 30 min in ST4 cells irradiated with 4 Gy and characterized by nuclear margination and fragmentation and the ability to exclude PI.…”

Down regulation of p53 with HPV E6 delays and modifies cell death in oxidant response of human diploid fibroblasts: an apoptosis-like cell death associated with mitosis

“…For example, Huang et al (2000b) show that arsenite induces cell death associated with mitosis in HeLa-S3 cells. Certain lymphoid cell lines respond to ionizing radiation by undergoing mitosis-associated cell death (Endlich et al, 2000). Our electron microscopy data suggest that E6 cells are arrested and die at prophase or prometaphase of mitosis.…”