%0 Journal Article %T Anticancer Effect of Fucoidan in Combination with Tyrosine Kinase Inhibitor Lapatinib %A Byeongsang Oh %A Jihun Kim %A Weidong Lu %A David Rosenthal %J Evidence-Based Complementary and Alternative Medicine %D 2014 %I Hindawi Publishing Corporation %R 10.1155/2014/865375 %X Background. Despite a number of in vitro and in vivo studies reporting the efficacy of fucoidan in treating various cancers, few studies have measured the efficacy of dietary fucoidan (DF) in combination with cancer drugs. Thus, we examined the sensitivity of DF in combination with the EGFR/ERBB2-targeting reagent lapatinib on cancer cells. Method. We selected six EGFR/ERBB2-amplified cancer cell lines (OE19, NCI-N87, OE33, ESO26, MKN7, and BT474) as an in vitro model and tested their sensitivity to DF alone and to DF in combination with the well-known EGFR/ERBB2-targeting reagent lapatinib. Result. Overall, in drug independent sensitivity test, DF alone did not significantly inhibit the growth of EGFR/ERBB2-amplified cancer cells in vitro. When DF was given in combination with lapatinib, however, it tended to synergistically inhibit cell growth in OE33 but antagonized the action of lapatinib in ESO26, NCI-N87, and OE19. Conclusion. This study suggests that DF has the potential to increase or decrease the effects of certain anticancer drugs on certain cancer cell types. Further study is needed to explore the mechanism of interaction and synergistic antitumor activity of DF in combination with chemotherapy and targeted therapy. 1. Introduction The use of dietary supplements (DS) is gaining in global popularity as a form of complementary and alternative medicine (CAM) [1, 2]. DS, defined as any product that contains vitamins, minerals, herbs or other botanicals, amino acids, enzymes, and/or other ingredients intended to supplement diet, is currently one of the most increasingly used CAM therapies [3]. A study found that 69% of the cancer patients in the US use DS following their cancer diagnosis [4]. A recent Australian survey with cancer patients also reported that approximately 69% of respondents had used one form of CAM in the previous year and 41% of them had visited a CAM practitioner [5]. Currently, thousands of DS products are available over the counter without health professionals¡¯ prescription, though the majority of DS have yet to be evaluated in clinical trials. Thus, most oncologists are concerned about possible herb-drug interactions that might occur with conventional anticancer drugs resulting in either excess toxicity or reduced efficacy [6]. A few studies have examined the interaction between herbs and chemotherapy drugs, but none have been examined yet to look at targeted agents [6]. And so, study on DS is essential to provide evidence-based information for cancer patients as well as healthcare practitioners. Fucoidan, one kind of DS, has %U http://www.hindawi.com/journals/ecam/2014/865375/