Apium graveolens Extract Inhibits Cell Proliferation and Expression of Vascular Endothelial Growth Factor and Induces Apoptosis in the Human Prostatic Carcinoma Cell Line LNCaP Tu ¨lay Ko ¨ken, 1 Bug˘ ra Koca, 1 Mete O ¨ zkurt, 2 Nilu ¨fer Erkasap, 2 Go ¨khan Kus x, 2 and Mustafa Karalar 3 Departments of 1 Clinical Biochemistry and 3 Urology, School of Medicine, Afyon Kocatepe University, Afyon, Turkey. Department of 2 Physiology, School of Medicine, Osmangazi University, Eskis xehir, Turkey. ABSTRACT Apium graveolens has been shown to inhibit the growth of a variety of cancer tissues. In this study, we investigated the anticancer effect of A. graveolens on the human prostatic carcinoma cell line LNCaP. LNCaP cells were treated with increasing concentrations of an ethanolic extract of A. graveolens ranging from 1000 to 3000 lg/mL, and viability was determined after 24 and 48 h using the XTT cell proliferation assay. The levels of cleaved poly (ADP-ribose) polymerase (PARP), one of the best biomarkers of apoptosis, were analyzed. Finally, quantitative gene expression analysis of vascular endothelial growth factor (VEGF), a critical mediator of angiogenesis, was performed using real-time reverse transcription– polymerase chain reaction. A. graveolens extract inhibited cell viability in both a time- and dose-dependent manner. Data from cleaved PARP assays suggested that A. graveolens caused induction of apoptosis in these cells. Treatment of cells with A. graveolens also resulted in downregulation of VEGF expression. This study showed that the antiproliferative effect exerted by an ethanolic extract of A. graveolens is triggered by induction of apoptosis. We also demonstrated that VEGF expression was downregulated by treatment with A. graveolens extract. KEYWORDS:  angiogenesis  Apium graveolens  apoptosis  prostatic carcinoma  vascular endothelial growth factor INTRODUCTION T he role of plant-derived products in the prevention of cancer has been confirmed by numerous laboratory and epidemiological findings. 1,2 One of these plants is Apium graveolens, which is also known as celery. 1 Many pharma- ceutical properties of A. graveolens have been described: antimicrobial, 3 anti-inflammatory, 4 antioxidant, 5,6 hepato- protective activity, 7 diuretic properties, and it can also help lower cholesterol levels. 8 In addition, celery seeds are used as a homeopathic treatment for rheumatism, arthritis, and gout. A. graveolens contains phenolic compounds, with the major phenolic acids being caffeic acid, p-coumaric acid, and ferulic acid, whereas the flavonoids present are apigenin, luteolin, and kaempferol. 5 During the last decade, apoptotic induction and inhibition of tumor angiogenesis have been new targets for anticancer drug discovery. 9,10 Cytostatic drugs that inhibit tumor cell proliferation and growth with low toxicity should be of in- terest for the research and treatment of cancer. A. graveolens and substances derived from it have been shown to inhibit growth and to induce apoptosis in various cancer tissues. They induce apoptosis of the human colon cancer cell line HCT116, 11 Dalton’s lymphoma ascites cells, 12 the human pancreatic cancer cell lines BxPC-3 and PANC-1, 13 the hu- man stomach cancer cell line BGC-823, 14 the mouse neuro- blastoma cell line neuro-2a, 15 the human cervical cancer cell line HeLa, 16 and the breast cancer cell line MCF-7. 17 How- ever, no further work on apoptotic effect on human prostate cancer cell line LNCap has been reported. Angiogenesis, which is initiated by particular tumor mi- croenvironmental conditions and several angiogenic factors, including vascular endothelial growth factor (VEGF), basic fibroblast growth factor, and platelet-derived growth factor, plays a principal crucial role during tumor development and metastasis. VEGF is the most important proangiogenic factor, and the level of VEGF is an important prognostic marker of tumor angiogenesis. 18 Thus, many antitumor and antiangiogenic strategies targeting VEGF have been devel- oped for inhibiting cancer angiogenesis, offering insights into the successful treatment of solid cancers. However, the side effects of anti-VEGF agents such as hypertension, bleeding, and gastrointestinal perforation, constrict their chronic use. 19 Considering these issues, there have recently been extensive studies done on plant-derived compounds and extracts that show potent antiangiogenic activity with the potential of overcoming the adverse effects of chemical compounds on human health. Manuscript received 21 February 2016. Revision accepted 11 October 2016. Address correspondence to: Tu¨lay Ko¨ken, MD, Department of Clinical Biochemistry, School of Medicine, Afyon Kocatepe University, Ali C xetinkaya Campuse B Block, 03200 Afyon, Turkey, E-mail: tkoken@aku.edu.tr JOURNAL OF MEDICINAL FOOD J Med Food 19 (12) 2016, 1166–1171 # Mary Ann Liebert, Inc., and Korean Society of Food Science and Nutrition DOI: 10.1089/jmf.2016.0061 1166