Effect of coumarin compound CHA-01 Clausena harmandiana (Pierre) Guillaumin on anti-proliferation activity in human cancer cell lines

Abstract

Clausena harmandiana (Pierre) Guillaumin or Song faa dong (in Thai), is classified in Family Rutaceae. Previous study, a coumarin compound designated CHA-01 was isolated from leave extract of C. harmandiana with inhibitory activity against calcium signaling in a ZDS1 null mutant yeast Saccharomyces cerevisiae (Δzds1). However, not much has been known on biological activity of this coumarin. In the past, some other coumarins were reported to contain anti-cancer activity. The aims of this research were to evaluate anti-proliferative activity of CHA-01 on several cancer cell lines and to study on molecular target(s) of CHA-01 in the Jurkat cells. The results revealed that CHA-01 showed anti-proliferative activity in several cell lines including Jurkat (Human acute T cell leukemia cell line), KATO III (Human gastric carcinoma cell line) and THP1 (Human acute monocytic leukemia cell line) by MTT assay. Jurkat T cell line was the most sensitity cell line to CHA-01 treatment with IC₅₀ value of 0.67±0.01 μM. It contained no cytotoxic activity against normal white blood cells and red blood cells. The CHA-01 treated Jurkat T cells arrested in S phase of the cell cycle. In addition, CHA-01 induced the cell death by apoptosis and inhibited DNA synthesis. Proteomic study of CHA-01 treated Jurkat cells for 60 minutes found total of 861 proteins. Among these, the proteins involved in cell proliferation, cell cycle and DNA synthesis were chosen. Some selected genes were cloned and studied for gene expression by quantitative real-time PCR. MCM4, POLD3 and NPM1 genes as well as their products were found to be down regulated while those of PRKACB and FADD were up regulated. The results suggested that CHA-01 might inhibit POLD3 and MCM4 genes expression that cause DNA synthesis inhibition, resulting in S phase cell cycle arrest. In addition, CHA-01 might activate PRKACB and FADD, hence the cells died from apoptosis and finally, the number of viable cells significantly decreased after CHA-01 treatment.