Soy milk digestion extract inhibits progression of prostate cancer cell growth via regulation of prostate cancer‑specific antigen and cell cycle-regulatory genes in human LNCaP cancer cells.
Soy milk, which is produced from whole soybeans, contains a variety of biologically active components. Isoflavones are a class of soy-derived phytoestrogens with beneficial effects, among which genistein (GEN) has been previously indicated to reduce the risk of prostate cancer. The present study evaluated the effects of soy milk digestion extract (SMD) on the progression of prostate cancer via the estrogen receptor (ER)β in human LNCaP prostate cancer cells. To evaluate the effects of SMD (daizein, 1.988 mg/100g, glycitein, 23.537 mg/100 g and GEN, 0.685 mg/100g) on cell proliferation, LNCaP cells were cultured in media containing vehicle (0.1% dimethyl sulfoxide), 17β‑estradiol (E2; 2.7x10‑7 mg/ml), GEN (2.7x10-2 mg/ml) of SMD (total aglycon concentration, 0.79 mg/ml), after which the cell viability was examined using an MTT assay. The cell viability was significantly elevated by E2 (by 45±0.18%), while it was markedly reduced by GEN (73.2±0.03%) or SMD (74.8±0.09%). Semi‑quantitative reverse transcription polymerase chain reaction analysis was performed to assess the mRNA expression levels of target genes, including ERβ, prostate cancer‑specific antigen (PSA) and cell cycle regulators p21, Cyclin D1 and cyclin-dependent kinase (CDK)4. The expression of ERβ was almost completely diminished by E2, whereas it was significantly elevated by SMD. In addition, the expression levels of PSA were considerably reduced by SMD. The expression of p21 was significantly elevated by SMD, while it was markedly reduced by E2. Of note, the expression levels of Cyclin D1 and CDK4 were considerably elevated by E2, while being significantly reduced by GEN and SMD. All of these results indicated that SMD may inhibit the proliferation of human prostate cancer cells via regulating the expression of ERβ, PSA, p21, Cyclin D1 and CDK4 in an ER-dependent manner.
Department of Nutrition and Functional Food Research, Central Research Institute, Dr Chung's Food Co., Ltd., Cheongju, Chungbuk 361‑782, Republic of Korea.
Nam-Hee
NH
Kang
Department of Nutrition and Functional Food Research, Central Research Institute, Dr Chung's Food Co., Ltd., Cheongju, Chungbuk 361‑782, Republic of Korea.
Hee-Chang
HC
Shin
Department of Nutrition and Functional Food Research, Central Research Institute, Dr Chung's Food Co., Ltd., Cheongju, Chungbuk 361‑782, Republic of Korea.
Seunghyun
S
Oh
Department of Nutrition and Functional Food Research, Central Research Institute, Dr Chung's Food Co., Ltd., Cheongju, Chungbuk 361‑782, Republic of Korea.
Kyun-Hee
KH
Lee
Department of Nutrition and Functional Food Research, Central Research Institute, Dr Chung's Food Co., Ltd., Cheongju, Chungbuk 361‑782, Republic of Korea.
Yoon-Bok
YB
Lee
Laboratory of Biochemistry and Immunology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea.
Kyung-Chul
KC
Choi
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D015415:Biomarkers; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D017430:Prostate-Specific Antigen / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism; D041942:Soy Milk / Q000737:chemistry
D000972:Antineoplastic Agents, Phytogenic; D015415:Biomarkers; D018797:Cell Cycle Proteins; D010936:Plant Extracts; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D017430:Prostate-Specific Antigen