Amygdalin Influences Bladder Cancer Cell Adhesion and Invasion In Vitro

Abstract

The cyanogenic diglucoside amygdalin, derived from Rosaceae kernels, is employed by many patients as an alternative anti-cancer treatment. However, whether amygdalin indeed acts as an anti-tumor agent is not clear. Metastasis blocking properties of amygdalin on bladder cancer cell lines was, therefore, investigated. Amygdalin (10 mg/ml) was applied to UMUC-3, TCCSUP or RT112 bladder cancer cells for 24 h or for 2 weeks. Tumor cell adhesion to vascular endothelium or to immobilized collagen as well as tumor cell migration was examined. Effects of drug treatment on integrin α and β subtypes, on integrin-linked kinase (ILK) and total and activated focal adhesion kinase (FAK) were also determined. Integrin knock-down was carried out to evaluate integrin influence on migration and adhesion. A 24 h or 2 week amygdalin application distinctly reduced tumor cell adhesion and migration of UMUC-3 and RT112 cells. TCCSUP adhesion was also reduced, but migration was elevated under amygdalin. Integrin subtype expression was significantly and specifically altered by amygdalin depending on the cell line. ILK was moderately, and activated FAK strongly, lost in all tumor cell lines in the presence of amygdalin. Knock down of β1 integrin caused a significant decrease in both adhesion and migration of UMUC-3 cells, but a significant increase in TCCSUP adhesion. Knock down of β4 integrin caused a significant decrease in migration of RT112 cells. Since the different actions of amygdalin on the different cell lines was mirrored by β1 or β4 knock down, it is postulated that amygdalin influences adhesion and migratory properties of bladder cancer cells by modulating β1 or β4 integrin expression. The amygdalin induced increase in TCCSUP migratory behavior indicates that any anti-tumor benefits from amygdalin (seen with the other two cell lines) may depend upon the cancer cell type.

Inhibition of cell growth and down-regulation of telomerase activity by amygdalin in human cancer cell lines

“…Moreover, our results showed that the amygdalin is efficiently induced to the inhibition of cell growth at ∼10 mg/ml concentration as reported in the previous studies (Shragg et al 1982;Chen et al 2013;Makarević et al 2014aMakarević et al , 2014b. However, we interestingly found that the normal somatic cells (MCR-5 fibroblasts) show considerable resistance to the cell growth and senescence at 10 mg/ml concentration of amygdalin.…”

“…Cell growth and proliferation were dose-dependently induced in UMUC-3, RT112 and TCCSUP bladder cancer cell lines treated with amygdalin, resulting in arrest of cell cycle progression by down-regulation of cdk2 and cyclin A (Makarević et al 2014a), and amygdalin treatment to SNU-C4 human colon cancer cells also displayed anticancer effect via down-regulation of cell cycle-related genes, implying that the amygdalin compound is induced to incomplete DNA synthesis (Park et al 2005). Furthermore, it has been demonstrated that apoptosis is induced by up-regulating caspase-3 activity and pro-apoptotic Bax protein, whereas down-regulating anti-apoptotic protein Bcl-2 in the amygdalin-treated HeLa cells (Chen et al 2013), human DU145 and LNCaP prostate cancer cells (Chang et al 2006).…”

“…Amygdalin, sometimes known as laetrile or vitamin B17, is one of the natural cyanogenic diglucoside existing in the fruits and nuts, such as cherries, apricots kernels, apples and almonds (Holzbecher et al 1984;Santos Pimenta et al 2014). It has been previously reported that amygdalin treatment in human cancer cells exerts a potential cytotoxic and anti-cancer effects by inducing apoptotic cell death (Syrigos et al 1998;Chang et al 2006;Chen et al 2013), arrest cell cycle through downregulation of cell cycle-related genes (Park et al 2005;Makarević et al 2014a) and blocking metastasis that can lead to the spread of cancer to other tissues (Makarević et al 2014b). Primarily, cancer has been treated by using conventional therapies; however, amygdalin is also used as an alternative medicine and was found one of the most useful and effective alternative in cancer therapy (Milazzo et al 2007;Sauer et al 2015).…”

Recent updates and future perspectives about amygdalin as a potential anticancer agent: A review

“…Then we evaluated the antitumor effects of amygdalin in bladder cancer, which ranked the first in the incidence of genitourinary tumors in China . Makarević et al detected tumor cell adhesion to vascular endothelial cells or migration of immobilized collagen and tumor cells, and observed the effects of amygdalin on integrin α and β subtypes, ILK (integrin‐linked kinase) and FAK (focal‐adhesion kinase) after treatment of bladder cancer UMUC‐3 and RT112 cells with amygdalin at a dose of 10 mg/mL for 24 hours or 48 hours; they knocked down integrin to evaluate the impact of integrin knockdown on cell migration and adhesion, and found that adhesion and migration of UMUC‐3 and RT112 cells were inhibited after amygdalin treatment, and at the time the expressions of integrin α and β subtypes, ILK and FAK were all decreased.…”

Amygdalin Regulates Apoptosis and Adhesion in Hs578T Triple-Negative Breast Cancer Cells

“…Amygdalin induced apoptosis of HeLa cervical cancer cells mediated by endogenous mitochondrial pathway ( Chen et al ., 2013 ). A recent study showed that amygdalin reduced adhesion and migration of UMUC-3 and RT112 bladder cancer cells through activation of focal adhesion kinase (FAK) and modulation of β1 integrin ( Makarević et al ., 2014 ).…”