Toxicology in Vitro 25 (2011) 999

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Toxicology in Vitro

journal homepage: www.elsevier .com/locate / toxinvi t

Letter to the Editor

Identity Crisis – Bladder cells in vascular biology

Dear Editor,We would like to call attention of worldwide readers of this

outstanding journal, including researchers, reviewers and mem-bers of editorial boards, to the increasingly and sometimes ne-glected use of cross-contaminated cell lines, particularly theECV304 cell line.

In the section articles in press appeared an article authored byWang et al. (doi:10.1016/j.tiv.2009.11.006), where they used thecell line ECV304 as a ‘‘human umbilical cord endothelial cell line”,as stated in the subheading Reagents inside Material and MethodsSection.

ECV304 was initially reported as a spontaneously transformedline derived from a Japanese human umbilical vein endothelialcells (HUVECs) culture (Takahashi et al., 1990; Takahashi andSawasaki, 1992) and represented an appropriate alternative modelto the time-consuming isolation and primary culture of humanumbilical vein endothelial cells for those researchers using thisin vitro model. However, a seminal report was published in 1999,indicating that ECV304 is a derivative of the human urinary blad-der carcinoma T24 cell line because of cross-contamination (Dirkset al., 1999).

The problem of cross-contamination has emerged as real prob-lem which seriously compromise the quality of research (Rojaset al., 2008). In spite of many efforts, the problem is still expandingand affects many cell lines used as classical in vitro models formany years. Noteworthy, the incidence of research papers flawedby the use of misidentified and cross-contaminated cell culture isestimated between 15% and 20%.

In regards to cross-contamination of ECV304, many efforts havebeen done by important cell and tissue repositories including theGerman Culture Collection of Microorganisms and Cell Cultures;the first in reporting the cross-contamination; The American TypeCulture Collection (ATTC); and the Japanese Collection of ResearchBioresources to spread out the information that ECV304 is a deriv-ative of T24. This information is explicitly stated in their cataloguesand websites and ATCC has even contact all customers who haspurchased this cell line at anytime, alerting them about it.

Unfortunately, an increasingly number of papers using ECV304as ‘‘endothelial” cell line are published every year in different jour-nals covering areas such as of cancer cell biology, vascular biology,pharmacological and toxicological testing, and many other disci-plines where endothelium plays an important role in physiologicalor pathophysiological contexts. Some authors have even argued itsusefulness considering some endothelial cell-like features displayed

0887-2333/$ - see front matter � 2010 Elsevier Ltd. All rights reserved.doi:10.1016/j.tiv.2010.01.007

by this cell line (Suda et al., 2001). However, all scientists shouldseriously take into consideration that ECV304 is not of HUVEC ori-gin and is therefore an inappropriate cell line to study endothelialcell biology.

This situation must be faced up with seriousness to stop theapparent unawareness of some researchers about the identity ofthis or other cell line(s). Collaborative actions involving research-ers, cell banks, journals and funding agencies are needed to savescientific reputation as well as many public or private resourcesthat are used to produce misleading data.

Conflict of interest statement

None declared.

References

Dirks, W.G., MacLeod, R.A.F., Drexler, H.G., 1999. ECV304 (endothelial) is really T24(bladder carcinoma): cell line cross-contamination at source. In Vitro Cell Dev.Biol. Anim. 35, 558–559.

Rojas, A., Gonzalez, I., Figueroa, H., 2008. Cell line cross-contamination inbiomedical research: a call to prevent unawareness. Acta Pharmacol. Sin. 29,877–880.

Suda, K., Rothen-Rutishauser, B., Günthert, M., Wunderli-Allenspach, H., 2001.Phenotypic characterization of human umbilical vein endothelial (ECV304) andurinary carcinoma (T24) cells: endothelial versus epithelial features. In VitroCell Dev. Biol. Anim. 37, 505–514.

Takahashi, K., Sawasaki, Y., 1992. Rare spontaneously transformed humanendothelial cell line provides useful research tool. In Vitro Cell Dev. Biol. 28A,380–382.

Takahashi, K., Sawasaki, Y., Hata, J., Mukai, K., Goto, T., 1990. Spontaneoustransformation and immortalization of human endothelial cells. In Vitro CellDev. Biol. 26, 265–274.

Armando RojasIleana Gonzalez

Jacqueline RomeroHector Figueroa

Biomedical Research Labs,Medicine Faculty, Catholic University of Maule,

Talca, Chile Biomedical Research Labs,Medicine Faculty, Catholic University of Maule,

3605 San Miguel Ave.,Talca, Chile

Tel.: +56 71 203134; fax: +56 71 413657.E-mail address: arojasr@ucm.cl (A. Rojas)

Available online 21 January 2010