Simultaneous but not sequential treatment with sodium butyrate improves the antiproliferative effect of alpha- or beta-interferon on a breast cancer cell line.

Clinical evidence indicates that alpha- and beta-interferon (alpha-IFN, beta-IFN) are only partially effective in human breast cancer. To improve their effectiveness, it has been proposed that differentiation inducers, such as sodium butyrate (NaB), be used to increase the IFN sensitivity of tumors. Therefore, we assessed concomitant or sequential combinations of low/intermediate concentrations of alpha-IFN or beta-IFN (10, 50 and 100 IU/ml) with a low concentration (0.

Effect of liposome-encapsulated alpha- or beta-interferon on breast cancer cell lines.

Experimental evidence and clinical studies have indicated that interferons (IFN) inhibit proliferation in a wide panel of neoplasms, including breast cancer. However, the antitumor activity of IFN requires the continuous presence of high concentrations of the drug and is associated with side effects. To explore the potential of liposomes as an IFN delivery system, we compared the effect of free or liposome-encapsulated alpha-IFN and beta-IFN on the growth of two breast cancer cell lines (MCF7 and MDA-MB231).

Effect of sodium butyrate on human breast cancer cell lines.

We have investigated the effects exerted by sodium butyrate (NaBu) on the growth and cell cycle perturbations of four human breast cancer cell lines (MCF7, T47D, MDA-MB231 and BT20) with different steroid receptor profiles. Moreover, since one of the supposed mechanisms of action for NaBu activity involves the induction of apoptosis, we have studied the effects of NaBu on DNA fragmentation by agarose gel electrophoresis and flow cytometry. In all investigated cell lines, NaBu exerted a time- and dose-dependent inhibition of growth and caused a maximum inhibitory effect (85% to 90%) at the concentration of 2.

Combined effect of tamoxifen or interferon-beta and 4-hydroxyphenylretinamide on the growth of breast cancer cell lines.

To improve the effectiveness of 4-hydroxyphenylretinamide (4-HPR), an analogue of retinoic acid used in chemoprevention and treatment of breast cancer, we investigated the effect of concomitant administration of 4-HPR (0.1, 1 microM) and tamoxifen (TAM, 0.1, 1 microM), or 4-HPR and interferon-beta (IFN-beta, 10, 100, 500 IU/ml) on the growth of four cell lines (MCF7, T47D, MDA-MB231 and BT20) characterized by a different steroid receptor profile.