Evaluation of antineoplastic action of 5-aza-2'-deoxycytidine (Dacogen) and docetaxel (Taxotere) on human breast, lung and prostate carcinoma cell lines.

The antineoplastic activity of 5-aza-2'-deoxycytidine (5-AZA-CdR) and docetaxel (Taxotere, Taxo) alone or in combination against human MDA-MB-231 breast, Calu-6 lung and DU-145 prostate carcinoma cell lines was evaluated by clonogenic assay. We also investigated by RT-PCR the capacity of these agents to re-activate the expression of E-cadherin and maspin, two tumor suppressor genes that were silenced by DNA methylation. 5-AZA-CdR and Taxo in combination produced a greater loss of clonogenicity than either agent alone. In MDA-MB-231 breast carcinoma cells, Taxo did not interfere with the re-activation of E-cadherin and maspin genes by 5-AZA-CdR. These results provide a rationale for clinical trials on the combination of 5-AZA-CdR and Taxo in patients with advanced cancer.