Yonsei Med J.  2015 Jan;56(1):16-23. 10.3349/ymj.2015.56.1.16.

Anthocyanin Induces Apoptosis of DU-145 Cells In Vitro and Inhibits Xenograft Growth of Prostate Cancer

• Ha US
• Bae WJ
• Kim SJ
• Yoon BI
• Hong SH
• Lee JY
• Hwang TK
• Hwang SY
• Wang Z
• Kim SW

• KMID: 2352784
• DOI: http://doi.org/10.3349/ymj.2015.56.1.16

Abstract

PURPOSE
To investigate the effects of anthocyanins extracted from black soybean, which have antioxidant activity, on apoptosis in vitro (in hormone refractory prostate cancer cells) and on tumor growth in vivo (in athymic nude mouse xenograft model).
MATERIALS AND METHODS
The growth and viability of DU-145 cells treated with anthocyanins were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and apoptosis was assessed by DNA laddering. Immunoblotting was conducted to evaluate differences in the expressions of p53, Bax, Bcl, androgen receptor (AR), and prostate specific antigen (PSA). To study the inhibitory effects of anthocyanins on tumor growth in vivo, DU-145 tumor xenografts were established in athymic nude mice. The anthocyanin group was treated with daily oral anthocyanin (8 mg/kg) for 14 weeks. After 2 weeks of treatment, DU-145 cells (2x106) were inoculated subcutaneously into the right flank to establish tumor xenografts. Tumor dimensions were measured twice a week using calipers and volumes were calculated.
RESULTS
Anthocyanin treatment of DU-145 cells resulted in 1) significant increase in apoptosis in a dose-dependent manner, 2) significant decrease in p53 and Bcl-2 expressions (with increased Bax expression), and 3) significant decrease in PSA and AR expressions. In the xenograft model, anthocyanin treatment significantly inhibit tumor growth.
CONCLUSION
This study suggests that anthocyanins from black soybean inhibit the progression of prostate cancer in vitro and in a xenograft model.

Keyword

Prostatic neoplasms; anthocyanins; apoptosis

MeSH Terms

Animals
Anthocyanins/*pharmacology
Apoptosis/*drug effects
Cell Line, Tumor
Cell Proliferation/drug effects
Cell Survival/drug effects
Gene Expression Regulation, Neoplastic/drug effects
Humans
Male
Mice, Inbred C57BL
Mice, Nude
NAD/metabolism
Prostate-Specific Antigen/metabolism
Prostatic Neoplasms/genetics/*pathology
Receptors, Androgen/metabolism
Tumor Suppressor Protein p53/metabolism
*Xenograft Model Antitumor Assays
bcl-2-Associated X Protein/genetics/metabolism
Anthocyanins
NAD
Prostate-Specific Antigen
Receptors, Androgen
Tumor Suppressor Protein p53
bcl-2-Associated X Protein

Figure

• 

  Fig. 1 Effect of anthocyanin on the viability and apoptosis of DU-145 cells. (A) DU-145 cells were treated with specified anthocyanin concentrations at each treatment time, and cell viability was determined by MTT assay. (B) Viability of DU-145 cells in specified anthocyanin concentrations after 24 hr. (C) Results of a DNA laddering assay in DU-145 cells treated with specified anthocyanin concentrations.

• 

  Fig. 2 The effect of anthocyanin on p53, Bax, and Bcl-2 Expression in DU-145 cells. (A) Western blot analysis of p53, Bax, and Bcl-2. (B) Densitometric analysis of Bax relative to β-actin. (C) Densitometric analysis of Bcl-2 relative to β-actin. (D) The relative ratio of Bax to Bcl-2. (E) Densitometric analysis of p53 relative to β-actin.

• 

  Fig. 3 The effect of anthocyanin on PSA and androgen receptor expression in DU-145 cells. (A) Western blot analysis of PSA and AR. (B) Densitometric analysis of PSA relative to β-actin. (C) Densitometric analysis of AR relative to β-actin. PSA, prostate specific antigen; AR, androgen receptor.

• 

  Fig. 4 The effect of anthocyanin on the ratio of NAD+ to NADH in DU-145 cells. NAD+, nicotinamide adenine dinucleotide.

• 

  Fig. 5 The effect of anthocyanin on tumor growth.

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