Resistance to some cancer chemotherapeutic drugs has been identified. One strategy to overcome that problem is by combining two or more of the drugs to get co-chemotherapeutic effects. A derivate chalcone, 3 -(4'-hydroxy-3'-methoxyphenyl)-1-phenyl-2-propene-1-on or para hydroxy meta methoxy chalcone (pHmMC), has been reported to have cytotoxic activity on some cancer cells through some pathways. The aim of this study was to investigate the effects of combinations of pHmMC and Doxorubicin (Dox) on the cytotoxicity, anti-proliferation, apoptosis, and the cell cycle of T47D (breast cancer cell-lines) in vitro. The cytotoxic and antiproliferative activity were determined by MTT (3-[4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay. The combination index (CI) was used to determine the synergistic, additive or antagonistic effects of the combinations. Flowcytometry method was performed to determine the combination effects on the apoptosis and cell cycle. The results indicated that the combinations had a higher inhibitory effect on the cell growth compared to those of single treatments of pHmMC and Dox. All the doses used in the combinations were lower of the single doses at their IC 50 s. The results showed all the combinations gave synergistic (CI: 0.3 -0.7) up to strong synergistic (CI: 0.1 -0.3) effects. The synergistic effects of the combinations were due to increased apoptosis and induced cell cycle arrest in S and G2/M phases on the cancer cell lines.

Cancer is a disease, a public health problem, which is found in the world as well as in Indonesia. In general, some of cancer theraphies are ineffective, characterized by the resistance performance of cancer cell line, the exposed normal cell and by the side effects. Nowadays, studies to fi nd the specifi c and safely anti-cancer drugs were increased by the time. Several studies revealed that Curcuma mangga Val. Rhizome contains some secondary metabolites, essential or non-essential oil, which has cytotoxic activities to the cancer cells. Based on these anti-cancer potentials, this study has several aims to recognize anti-cancer selectivity and molecular mechanism by inducting apoptosis and inhibiting myeloma cell proliferation. To C. mangga Val. essential oil, immunocyto chemical test was performed to determine the expression of p53, caspase-9, Bcl-2, H-Ras protein while TUNEL test was performed to determine the number of apoptosis cells.The results of this study shown that anti-cancer molecular mechanism of C. mangga Val. essential oil to myeloma cell line was performed by increasing apoptosis; by increasing the expression of pro-apoptosis p53, caspase-9 protein and reducing protein which is increasing proliferation Bcl-2 and H-Ras.