Cisplatin (CDDP) is widely used to treat several types of cancer. However, CDDP induces nephrotoxicity. This toxicity could be avoided, applying a lower cisplatin dose; however, it could induce a lesser therapeutic activity. In this paper, we present the cytotoxic activity against prostate human cancer cell line (PC-3) of the combination of CDDP with masticadienonic acid (MDA), a triterpene isolated from Amphypterygium adstringens.The combinations A (half of the IC₅₀), B (IC₅₀) and C (twice IC₅₀ of the compounds) in a radio 1:1 were evaluated. Our results showed that the B and C combinations presented synergism effect. However, B combination showed almost 100% inhibition of cell proliferative activity and increased apoptosis compared with those presented by each compound apart. A pretreatment of MDA 24 h to cells before the CDDP, AMD or B combination administration result in a resistance to the treatments. A xenograft study using PC-3 cells showed that the combination of 47.5 mM/kg (AMD) plus 4 mM/kg (CDDP) administered weekly for 3 weeks reducing the tumor volume in approximately 47 %. However, the combination of 47.5 mg/kg (AMD) plus 2 mg/kg (CDDP) administered every third day for 21 days reduce, approximately 82% of tumor compared with mice no treated.

Clinical evidence has shown that bacterial infections are more difficult to eradicate when form-ing a biofilm aggregate than when are produced by bacteria in planktonic form. Therefore, com-pounds that inhibit biofilm formation could be used against severe infections. It has been re-ported that bromo 2-(5H) furanones inhibited biofilm formation by their anti-quorum sensing properties. To determine if the 2-(5H) furanone moiety is essential to induce inhibition of biofilm formation, we evaluated ten halogen 2-(5H) furanones derivates previously synthesized. Besides evaluating the inhibition of biofilm formation, we assessed pyocyanin production, swarming motility, and transcription of essential QS genes: rsaL, rhlA, pqsA and phz1 genes. Our results showed that although three bromo-furan-2(5H)-one-type derivatives (A1-A3) and two bromo-4-(phenylamino)-furan-2(5H)-one-type compounds (B2 and B6) inhibited the biofilm formation in both P. aeruginosa PA14 (reference) and PA64 (drug-resistant) strains only the furanones A1-A3 were efficient to inhibit QSS.