## 2 Bioactive Compounds
### Quercetin  
Quercetin is found in a variety of foods such as apple (4.01 mg/g fresh weight), chili pepper (32.6 mg/100 g fresh weight), blueberry (14.6 mg/g fresh weight), cherry (17.4 mg/g fresh weight), and cranberry (25.0 mg/g fresh weight). Quercetin is also present in black tea (2.50 mg/100 mL) and red wine (3.16 mg/100 mL) [112]. The anti-cancer effects of quercetin have been widely studied using different models of cancer including liver, prostate, breast, lung, ovarian and cervical. Quercetin suppresses tumor growth and increases the survival rate of nude mice grafted with HepG2 human hepatocarcinoma cells, which is likely via the reduction of cyclinD1 expression in the tumors [122]. In addition, quercetin induces apoptosis by interfering with the cell cycle of human hepatocellular carcinoma LM3 cells, and simultaneously induces autophagy by down-regulating JAK2 and STAT3 activity, thereby protecting against the progress of hepatocarcinoma [123]. Quercetin reverses docetaxel resistance by modulating the androgen receptor expression and the PI3K/Akt signaling pathway in prostate cancer cells (LNCaP/R, PC-3/R) [123]. Moreover, quercetin treatment markedly decreases MALAT1 protein expression dose- and time-dependently in PC cells, thus inhibiting epithelial-to-mesenchymal transition (EMT) and inducing apoptosis [124]. This indicates that quercetin has protective effects against prostate cancer development [124]. The anti-cancer effects of quercetin are likely attributable to its induction of apoptosis, which has been evaluated in 9 different tumor cell lines [125]. Annexin V/PI staining indicates that quercetin significantly promotes apoptosis, especially in CT-26, LNCaP, MOLT-4, and Raji cell lines, while also reducing tumor volume significantly in MCF-7 and CT-26 mice [125]. [PERSON] et al. investigated the possibility that quercetin can overcome cisplatin-induced side effects. Interestingly, quercetin mitigated kidney toxicity, a potential side effect of cisplatin treatment, while cisplatin and quercetin together increased anti-tumor effects compared to the controls in EMT6 breast tumor-bearing mice [126]. In addition to the mitigation of side effects, quercetin also enhanced the anti-tumor effects of BET inhibitors in a xenograft model of pancreatic cancer [127]. Simultaneous treatment with quercetin and a BET inhibitor induced apoptosis and suppressed cell growth, while reducing hnRNPA1 expression in vivo, thereby enhancing the anti-tumor effect of the BET inhibitor [127]. These studies suggest that quercetin can be synergistically used with current cancer treatments under development. Quercetin also suppressed cancer metastasis including lung cancer via inhibition of Snail-dependent Akt activation and Snail-independent ADAM9 expression pathways [128]. Quercetin also increased radio-sensitivity of human -covarian cancer cells, which was mediated by p53-dependent endoplasmic reticulum stress pathways [129]. The anti-cancer effects included the induction of apoptosis, DNA damage, and inhibition of G2-M cell cycle arrest, which were associated with the up-regulation of caspase and pro-apoptosis genes, as well as the down-regulation of PI3K, MAPK, and WNT-mediated signaling pathways [130].