Doxorubicin response in a triple negative breast cancer cell model: long-term resistance versus short-term stress

We have used a cell model for triple negative breast cancer, CAL51 cells, to study the transcriptional profiling of chemotherapy drug response. A doxorubicin resistant derivative has been generated, named CALDOX, which is able to proliferate in the continuos presence of 0.4 micro molar doxorubicin in the culture medium. In addition, both naive CAL51 and drug resistant CALDOX cells, the short-term response to doxorubicin treatment has been studied. CAL51 cells were treated with 0.4 micro M doxorubicin until they were able to survive and proliferate in the presence of drug (these drug resistant cells are termed CALDOX). Short-term effects of doxorubicin were studied in CAL51 cells (with treatments for 24 and 48 h with 0.4 micro M doxorubicin) and CALDOX cells (with treatment for 24 h with 4 micro M doxorubicin). For the array experiment, RNA isolated from three independent cultures were used for each condition.