To determine the chemopreventive potential of alyssin and iberin, the in vitro anticancer activities and molecular targets of isothiocyanates (ITCs) were measured and compared to sulforaphane in hepatocellular carcinoma cell HepG2. The SR-FTIR spectra observed a similar pattern vis-à-vis the biomolecular alteration amongst the ITCs-treated cells suggesting a similar mode of action. All of the ITCs in this study cause cancer cell death through both apoptosis and necrosis in concentration dependent manner (20-80 μM). We found no interactions of any of the ITCs studied with DNA. Notwithstanding, all of the ITCs studied increased intracellular reactive oxygen species (ROS) and suppressed tubulin polymerization, which led to cell-cycle arrest in the S and G2/M phase. Alyssin possessed the most potent anticancer ability; possibly due to its ability to increase intracellular ROS rather than tubulin depolymerization. Nevertheless, the structural influence of alkyl chain length on anticancer capabilities of ITCs remains inconclusive. The results of this study indicate an optional, potent ITC (viz., alyssin) because of its underlying mechanisms against hepatic cancer. As a consequence, further selection and development of effective chemotherapeutic ITCs is recommended.

ObjectiveTo analyze two isothiocyanates (sulforaphene and sulforaphane) and their antiproliferative effect of 11 indigenous cruciferous vegetables.MethodsPhytoconstituents identification was conducted by high performance liquid chromatography and gas chromatography-mass spectrometer techniques. The antiproliferation was evaluated in colon cancer cell line HCT116 by MTT assay.ResultsIsothiocyanate identification by high performance liquid chromatography showed that broccoli, cabbage, “Khi-Hood” (Raphanus sativus L. var. caudatus Alef) and Chinese radish contained isothiocyanates sulforaphane. Sulforaphene and sulforaphane in broccoli, cabbage and “Khi-Hood” were characterized by the gas chromatography-mass spectrometer analysis. Antiproliferation screening by MTT assay found that the potent plants which possessed IC50 below 50 μg/mL were cabbage and “Khi-Hood”, while the others had low antiproliferation with IC50 higher than 50 μg/mL. Difference in antiproliferation was probably due to difference existed phytochemical constituents in each plant. “Khi-Hood” possessed the highest antiproliferation against HCT116 with the lowest IC50 at (9.42 ± 0.46) μg/mL. The IC50 of chemotherapeutic drug (mitomycin C) was (19.12 ± 1.00) μg/mL, while both melphalan and 5-fluorouracil possessed the IC50 value higher than 50 μg/mL.ConclusionsCommonly consumed cruciferous vegetables exerted varied antiproliferation and isothiocyanate contents. High isothiocyanate content in “Khi-Hood” was contributed to high antiproliferation. Among 11 plants studied, “Khi-Hood” could be an alternative chemopreventive diet

Owing to the crucial role of Src in cancer metastasis, interruption of Src and its signaling has been considered a promising strategy for cancer metastasis treatment. Cucurbitacin B, a dietary triterpenoid, has been shown to possess anti-proliferative and apoptosis-inducing activities in cholangiocarcinoma (CCA) cells via suppressing the activation of FAK which is a main downstream Src effector. We hypothesized that cucurbitacin B might act as a Src suppressant which conferring anti-metastasis effect against CCA cells. To investigate this, the role of Src in regulating metastasis behavior of CCA cells and the effect of cucurbitacin B on Src-mediated metastatic phenotype of these cells were determined. The results showed that activation of Src significantly enhanced the migratory and invasive abilities of CCA cells. Molecular analysis revealed that Src-facilitated metastasis behavior of CCA cells occurred by modifying expression of a wide range of metastasis-related genes in the cells. Consistent with gene expression results, activation of Src significantly induced the protein expression of 2 important metastasis-associated molecules, MMP-9 and VEGF. Cucurbitacin B markedly suppressed activation of Src and its key effector, FAK. As a consequence, the alteration of expression profiles of metastasis-associated genes induced by Src activator in CCA cells was diminished by cucurbitacin B treatment. The compound also down-regulated Src-induced expression of MMP-9 and VEGF proteins in the cells. Moreover, molecular docking analysis revealed that cucurbitacin B could interact with Src kinase domain and possibly restrain the kinase from being activated by hindering the ATP binding. In conclusion, cucurbitacin B exhibited anti-metastatic property in CCA cells via negatively influencing Src and Src-related oncogenic signaling. This compound may therefore be a potential therapeutic drug for further development as an anti-Src agent for treatment of metastatic CCA.

L-type amino acid transporter 1 (LAT1) is an amino acid transporter that is overexpressed in several types of cancer and, thus, it can be a potential target for chemotherapy. The objectives of this study were to (a) synthesize LAT1-targeted chlorambucil derivatives and (b) evaluate their LAT1-mediated cellular uptake as well as antiproliferative activity in vitro in the human breast cancer MCF-7 cell line. Chlorambucil was conjugated to l-tyrosine—an endogenous LAT1 substrate—via either ester or amide linkage (compounds 1 and 2, respectively). While chlorambucil itself did not bind to LAT1, its derivatives 1 and 2 bound to LAT1 with a similar affinity as with l-tyrosine and their respective cellular uptake was significantly higher than that of chlorambucil in MCF-7. The results of our cellular uptake study are indicative of antiproliferative activity, as a higher intracellular uptake of chlorambucil derivatives resulted in greater cytotoxicity than chlorambucil by itself. LAT1 thus contributes to intracellular uptake of chlorambucil derivatives and, therefore, increases antiproliferative activity. The understanding gained from our research can be used in the development of LAT1-targeted anticancer drugs and prodrugs for site-selective and enhanced chemotherapeutic activity.