Apoptotic death in epithelial cells: Cleavage of DNA to 300 and/or 50 kb fragments prior to or in the absence of internucleosomal fragmentation

Author(s): Oberhammer F, Wilson JW, Dive C, Morris ID, Hickman JA et al.

Abstract

To date, apoptosis has been characterized biochemically by the production of 180-200 bp internucleosomal DNA fragments resulting from the activation of an endonuclease(s). The principal morphological feature of apoptosis is the condensation of chromatin and it has been assumed that this may reflect the oligonucleosomal fragmentation pattern. We have re-examined this dogma by comparing the biochemical and morphological features of cell death in several epithelial cell types (HT-29-I1 colon adenocarcinoma, CC164 mink lung, DU-145 human prostatic carcinoma and MCF-7 human breast adenocarcinoma) and one mesenchymal cell line (H11ras-R3 ras-transformed rat fibroblasts). Cell death was induced either by serum deprivation, TGF-beta 1 or etoposide, or by leaving cells to reach confluence. Cell death was assessed with respect to detachment from monolayers, morphological changes and DNA integrity. The DNA-binding fluorophore Hoechst 33258 revealed chromatin condensation patterns consistent with apoptotic cell death in all cell types except MCF-7 cells. Using field inversion gel electrophoresis in conjunction with conventional 2% agarose gel electrophoresis, cleavage of DNA to 50 kbp fragments was observed in all cases except MCF-7 cells. This preceded the appearance of oligonucleosomal fragments in HT-29-I1, CC164 and H11ras-R3 cells. Although the DNA of DU-145 cells fragmented into 50 kbp units, and although the cells exhibited classical apoptotic morphology, no subsequent internucleosomal cleavage was observed. These results suggest that changes in the integrity of DNA indicative of the release of chromatin loop domains occur before cleavage at internucleosomal sites is initiated and that the latter is not an essential step in the apoptotic process.

Similar Articles

Folic acid-CdTe quantum dot conjugates and their applications for cancer cell targeting

Author(s): Suriamoorthy P, Zhang X, Hao G, Joly AG, Singh S, et al.

A method to predict breast cancer stage using Medicare claims

Author(s): Smith GL, Shih YC, Giordano SH, Smith BD, Buchholz TA

Toxic potential of materials at the nanolevel

Author(s): Nel A, Xia T, M├Ądler L, Li N

From nanotechnology to nanomedicine: applications to cancer research

Author(s): Seigneuric R, Markey L, Nuyten DS, Dubernet C, Evelo CT, et al.

Superparamagnetic iron oxide nanoparticle probes for molecular imaging

Author(s): Thorek DL, Chen AK, Czupryna J, Tsourkas A

Freeze-drying of nanoparticles: formulation, process and storage considerations

Author(s): Abdelwahed W, Degobert G, Stainmesse S, Fessi H

Annexin V for flow cytometric detection of phosphatidylserine expression on B cells undergoing apoptosis

Author(s): Koopman G, Reutelingsperger CP, Kuijten GA, Keehnen RM, Pals ST, et al.

Synthesis of gold nanotriangles and silver nanoparticles using Aloe vera plant extract

Author(s): Chandran SP, Chaudhary M, Pasricha R, Ahmad A, Sastry M

Facile green synthesis of variable metallic gold nanoparticle using Padinagymnospora, a brown marine macroalga

Author(s): Singh M, Kalaivani R, Manikandan S, Sangeetha N, Kumaraguru AK

Gold nanoparticles: From nanomedicine to nanosensing

Author(s): Chen PC, Mwakwari SC, Oyelere AK

Near-infrared resonant nanoshells for combined optical imaging and photothermal cancer therapy

Author(s): Gobin AM, Lee MH, Halas NJ, James WD, Drezek RA, et al.

Biological applications of gold nanoparticles

Author(s): Sperling RA, Rivera Gil P, Zhang F, Zanella M, Parak WJ

Gold nanoparticles for biology and medicine

Author(s): Giljohann DA, Seferos DS, Daniel WL, Massich MD, Patel PC, et al.

Reperfusion induces myocardial apoptotic cell death

Author(s): Zhao ZQ, Nakamura M, Wang NP, Wilcox JN, Shearer S, et al.

Asbestos causes apoptosis in alveolar epithelial cells: role of iron-induced free radicals

Author(s): Aljandali A, Pollack H, Yeldandi A, Li Y, Weitzman SA, et al.

Distinct cytotoxic mechanisms of pristine versus hydroxylated fullerene

Author(s): Isakovic A, Markovic Z, Todorovic-Markovic B, Nikolic N, Vranjes-Djuric S, et al.

In vitro testing of the potential for orthopedic bone cements to cause apoptosis of osteoblast-like cells

Author(s): Ciapetti G, Granchi D, Savarino L, Cenni E, Magrini E, et al.