Anticancer Efficacy of the Combination of Berberine and PEGylated Liposomal Doxorubicin in Meth A Sarcoma-Bearing Mice.

Berberine, the main isoquinoline alkaloid obtained from traditional plants, e.g., Berberis, Coptis, Coscinium spps., etc., is known to exhibit anticancer activity in vitro and in vivo. In this study, the anticancer potential of berberine combined with PEGylated liposomal doxorubicin (polyethylene glycol (PEG)-lip-DOX) was investigated. At first, the effect of berberine on endothelial cells was examined in vitro by use of human umbilical vein endothelial cells (HUVECs): Berberine inhibited HUVEC growth with an IC50 at 24 h of about 144 µg/mL and that at 72 h of about 29 µg/mL. In contrast, less than 50 µg/mL berberine inhibited the vascular endothelial growth factor (VEGF) expression to some extent after a 24-h incubation, suggesting that berberine suppressed angiogenic action under the condition of little cytotoxicity. Next, the in vivo anticancer activity of the combination of berberine (intraperitoneally (i.p.)) and PEG-lip-DOX (intravenously (i.v.)) was examined in Meth A sarcoma-transplanted BALB/c mice. The results showed that either berberine or PEG-lip-DOX exhibited antiproliferative activity against Meth A cells. Moreover, treatment with the combination of berberine and PEG-lip-DOX suppressed the tumor growth more strongly than that with berberine or PEG-lip-DOX alone. Based on these findings, the combination cancer chemotherapy with berberine and PEGylated liposomal doxorubicin may be beneficial for the treatment of cancer.

Inhibitory effect of liposomal rhinacanthin-N isolated from Rhinacanthus nasutus on pulmonary metastasis in mice.

We previously observed that rhinacanthins, which are the main naphthoquinone esters isolated from the roots of a Thai medicinal plant, Rhinacanthus nasutus KURZ. (family Acanthaceae), suppress the growth of Meth-A sarcoma in the tumor-bearing mice and that rhinacanthin-N has the strongest antitumor activity among these naphthoquinone esters tested. In the present study, we investigated the effect of rhinacanthin-N on pulmonary metastasis induced by B16F10 melanoma cells in mice. C57BL/6 male mice were injected intravenously with B16F10 melanoma cells, and liposomal rhinacanthin-N was administered intraperitoneally from day 1 to 7 after tumor implantation. Liposomes were used to formulate an injectable form of the hydrophobic agent. Treatment of the mice with 5 or 10 mg/kg/d of liposomal rhinacanthin-N significantly inhibited the pulmonary metastatic colonization of the melanoma cells. Based on these data, our findings demonstrate that rhinacanthin-N possesses antimetastatic efficacy, which may make it a lead compound for the development of a new anticancer drug for use in cancer chemotherapy.

Characteristics and anticancer properties of bacterial cellulose films containing ethanolic extract of mangosteen peel.

Bacterial cellulose (BC) films containing an ethanolic extract of mangosteen peel were prepared and their physical, chemical, and anticancer properties were characterized. The cumulative absorption and release profiles of bioactive compounds in the films were determined based on total phenolic and α-mangostin content. The BC films were filled with total phenolic compounds expressed as gallic acid equivalent varying from 4.72 to 275.91 mg/cm3 dried film, and α-mangostin varying from 2.06 to 248.20 mg/cm3 dried film. A Fourier transform infrared spectroscopy evaluation showed that there were weak interactions between the functional groups of the extract and the BC. Decreases in the water absorption capacity and water vapor transmission rate of the modified films were detected. Release studies were performed using Franz diffusion cells. In a non-transdermal system, the release of bioactive compounds from the films depended on concentration, immersion time, and the pH of the dissolution medium. A transdermal diffusion study showed that 59-62% of total phenolic compounds that were initially loaded were released from the films and more than 95% of bioactive compounds released from the films were adsorbed into pig skin. Only very small amount of the bioactive compounds penetrated through pig skin and into phosphate and acetate buffers. In studies of anticancer abilities, the release of 2.0 µg/ml α-mangostin from the BC films could suppress the growth of B16F10 melanoma (approximately 31% survival). With the release of α-mangostin at greater than 17.4-18.4 µg/ml, less than 15 and 5% survival of B16F10 melanoma and MCF-7 breast cancer cells, respectively, was observed.

Suppression in mice of immunosurveillance against PEGylated liposomes by encapsulated doxorubicin.

PEGylated liposomes (PEG-lip) can escape from recognition by immune system and show a longer half-life in the blood than non-PEGylated liposomes. In this study, we investigated the influence of injected PEG-lip encapsulating doxorubicin (PEG-lip-DOX) on the biodistribution of subsequently injected PEG-lip in mice. PEG-lip-DOX, free doxorubicin or empty PEG-lip were initially injected into BALB/c mice via a tail vein, and 3days later [(3)H]-labeled PEG-lip ([(3)H] PEG-lip) were injected into these same mice. At 24h after the injection, the distribution of [(3)H] PEG-lip in the liver and spleen was significantly reduced in the PEG-lip-DOX group compared with that in the free doxorubicin or PEG-lip group. Consequently, the plasma concentration of [(3)H] PEG-lip was significantly elevated by the pretreatment with PEG-lip-DOX. Altered pharmacokinetics was observed at least until 72h after the injection of [(3)H] PEG-lip. The influence of the injected PEG-lip-DOX on the pharmacokinetics of the subsequently injected [(3)H] PEG-lip was clearly observed from 1 to 14days, and slightly observed on days 21 and 28, after the injection of the PEG-lip-DOX. Flow cytometric analysis showed that the number of liver Kupffer cells was significantly reduced after the treatment with PEG-lip-DOX. On the other hand, a similar alteration in the distribution of the subsequently injected [(3)H] PEG-lip was observed in immunodeficient mice such as BALB/c nu/nu and severe combined immunodeficiency (SCID) mice. These findings suggest that immune cells including liver Kupffer cells responsible for recognizing PEG-lip were selectively damaged by the encapsulated doxorubicin in PEG-lip injected initially, which damage led to prolongation of the half-life of subsequently injected [(3)H] PEG-lip in the blood.

Antitumor activity of liposomal naphthoquinone esters isolated from Thai medicinal plant: Rhinacanthus nasutus KURZ.

We previously observed that rhinacanthins-C, -N and -Q, three main naphthoquinone esters isolated from the roots of Thai medicinal plant; Rhinacanthus nasutus KURZ. (Acanthaceae) induced apoptosis of human cervical carcinoma HeLaS3 cells. Since these rhinacanthins showed limited solubility in aqueous medium, we attempted to entrap them into liposomal membrane: Liposomalization enabled injection of the drugs and the drugs were expected to transfer to lipoproteins in the bloodstream. Liposomal formulations of rhinacanthins-C, -N and -Q showed strong antiproliferative activity against HeLaS3 cells with the IC50 values of 32, 17, 70 microM; 19, 17, 52 microM and 2.7, 2.0 and 5.0 microM for the exposure time of 24, 48, and 72 h, respectively. These liposomes suppressed the tumor growth in Meth-A sarcoma-bearing BALB/c mice at the dose of 5.0 mg/kg/d for 10 d. Among rhinacanthins, liposomal rhinacanthin-N significantly suppressed solid tumor growth. Based on these results, our findings demonstrated that rhinacanthin-N suppressed tumor growth in vivo, and suggested that liposomes are useful for preparing injectable formulation of hydrophobic drugs.