Proteomic-based identification of multiple pathways underlying n-butylidenephthalide-induced apoptosis in LNCaP human prostate cancer cells

Abstract

Although numerous studies have shown the cancer-preventive properties of butylidenephthalide (BP), there is little report of BP affecting human prostate cancer cells. In the present study, proteomic-based approaches were used to elucidate the anticancer mechanism of BP in LNCaP human prostate cancer cells. BP treatment decreased the viability of LNCaP human prostate cancer cells in a concentration- and time-dependent manner, which was correlated with G0/G1 phase cell cycle arrest. Increased cell cycle arrest was associated with a decrease in the level of CCND1, CDK2, and PCNA proteins and an increase in the level of CDKN2A, CDKN1A, and SFN proteins. Proteomic studies revealed that among 48 differentially expressed proteins, 25 proteins were down-regulated and 23 proteins were up-regulated and these proteins fall into one large protein protein interaction network. Among these proteins, FAS, AIFM1, BIK, CYCS, SFN, PPP2R1A, CALR, HSPA5, DDIT3, and ERN1 are apoptosis and endoplasmic reticulum (ER) stress associated proteins. Proteomic data suggested that multiple signaling pathways including FAS-dependent pathway, mitochondrial pathway, and ER stress pathway are involved in the apoptosis induced by BP.

Keywords: 2DE; 3-(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate; 3-(4,5-dimethyl thizol-2-yl)-2,5-diphenyl tetrazolium bromide; ABC; ACN; Apoptosis; B-cell lymphoma 2; BAD; BCL2; BCL2 antagonist of cell death; BP; Butylidenephthalide; CCND1; CDC25A; CDK; CHAPS; Cell cycle; DMSO; DTE; EDTA; ER; IEF; IPG; LC/MS/MS; LNCaP human prostate cancer; MTT; NL; PAGE; PANTHER; PBS; PI; Proteomics; RPMI; Roswell Park Memorial Institute; SDS; STRING; TBST; TUNEL; acetonitrile; ammonium bicarbonate; cell division cycle 25 homolog A; cyclin D1; cyclin dependent kinase; dimethyl sulfoxide; dithiolerythritol; endoplasmic reticulum; ethylenediaminetetraacetic acid; immobilized pH gradient; isoelectric focusing; liquid chromatography tandem mass spectrometry; n-butylidenephthalide; non-linear; phosphate-buffered saline; polyacrylamide gel electrophoresis; propidium iodide; protein analysis through evolutionary relationships; search tool for the retrieval of interacting genes/proteins; sodium dodecyl sulfate; terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling, other proteins which are not mentioned above are denoted as their gene symbols as listed in Table 2; tris-buffered saline Tween-20; two-dimensional gel electrophoresis.