γ-Tocotrienol induces paraptosis-like cell death in human colon carcinoma SW620 cells.

Colorectal cancer is one of the most serious illnesses among diagnosed cancer. As a new type of anti-cancer composition from tocotrienol-rich fraction of palm oil, γ-tocotrienol is widely used in anti-cancer research. The objectives of this study were to investigate the effects of γ-tocotrienol on human colon cancer SW620 and HCT-8 cells.

A paraptosis-like cell death induced by δ-tocotrienol in human colon carcinoma SW620 cells is associated with the suppression of the Wnt signaling pathway.

Tocotrienol is considered a beneficial effect agent on inhibition of tumor development. In this study, we focused on the effects of δ-tocotrienol and its possible mechanism on induction of death in human colon cancer SW620 cells. δ-Tocotrienol inhibited proliferation of SW620 cell in a dose-dependent manner.

γ-Tocotrienol inhibits angiogenesis of human umbilical vein endothelial cell induced by cancer cell.

Antiangiogenic therapy mediated by food components is an established strategy for cancer chemoprevention. Growth factors play critical roles in tumor angiogenesis. A conditioned medium containing growth factors from human gastric adenocarcinoma SGC-7901 cell conditioned medium was used as an angiogenic stimulus in this study.

Growth inhibition effect of β-catenin small interfering RNA-mediated gene silencing on human colon carcinoma HT-29 cells.

The β-catenin gene is a critical component of Wnt signaling pathway. Aberrant activation of Wnt/β-catenin signaling and subsequent upregulation of β-catenin is related to enhancing cell proliferation and developing colon polyps and colon cancer. In the present study, the effect of β-catenin knockdown on the growth and survival of the human colon cancer cell line HT-29 was investigated in vitro.

gamma-Tocotrienol modulates the paracrine secretion of VEGF induced by cobalt(II) chloride via ERK signaling pathway in gastric adenocarcinoma SGC-7901 cell line.

Hypoxia is a common characteristic feature of solid tumors, and carcinoma cells are known to secrete many growth factors. These growth factors, such as vascular endothelial growth factor (VEGF), play a major role in the regulation of tumor angiogenesis and metastasis. In this study, the effect of gamma-tocotrienol, a natural product commonly found in palm oil and rice bran, on the accumulation of HIF-1alpha protein and the paracrine secretion of VEGF in human gastric adenocarcinoma SGC-7901 cell line induced by cobalt(II) chloride (as a hypoxia mimic) was investigated.

Effects of beta-ionone on mammary carcinogenesis and antioxidant status in rats treated with DMBA.

Recent chemopreventive studies from our group showed that dietary beta -ionone inhibited 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis by the inhibition of cell proliferation and apoptosis initiation. In this study, we examined the chemopreventive effects of varied doses of dietary beta -ionone on the development and growth of DMBA-induced rat mammary tumors as well as plasma antioxidant status. beta -ionone treatment groups were given 9, 18, and 36 mmol/kg in the AIN76A diet starting 2 wk prior to DMBA administration and continuing for the 24 wk.

Inhibitory effects of gamma-tocotrienol on invasion and metastasis of human gastric adenocarcinoma SGC-7901 cells.

Natural vitamin E is a mixture of two classes of compounds, tocopherols and tocotrienols. Recent research has revealed that tocotrienols, especially gamma-tocotrienol, exhibit not only the same antioxidant ability as tocopherols, but also remarkable anticancer capacity in cancer cell lines. In this study, the invasion and metastatic capacities of gastric adenocarcinoma SGC-7901 cells and the correlation with antimetastasis mechanisms induced by gamma-tocotrienol were explored.

Inhibition of proliferation and induction of apoptosis by gamma-tocotrienol in human colon carcinoma HT-29 cells.

Objective: gamma-Tocotrienol is a major component of the tocotrienol-rich fraction of palm oil, but there is limited evidence that it has antitumor activity. In particular, the effects of gamma-tocotrienol on human colon carcinoma cells have not been reported. To investigate the chemopreventive effects of gamma-tocotrienol on colon cancer, we examined its capacity to inhibit proliferation and induce apoptosis in HT-29 cells and explored the mechanism underlying these effects.

Fresh apples suppress mammary carcinogenesis and proliferative activity and induce apoptosis in mammary tumors of the Sprague-Dawley rat.

Whole apple extracts possess potent antioxidant activity and antiproliferative activity against cancer cells in vitro. The objectives of this study were to determine the anticancer activity of apple extracts in a rat mammary cancer model induced by 7,12-dimethylbenz(a)anthracene (DMBA) in vivo and to determine if apple extracts inhibited cell proliferation and affected apoptosis in mammary cancer tissues in vivo. Rats were given the whole apple extracts (0, 3.

Genotoxicity of water from the Songhua River, China, in 1994-1995 and 2002-2003: Potential risks for human health.

A previous study showed that the cancer mortalities are higher for residents who lived nearby the Songhua River heavily polluted by organic contamination. It is important to determine its risk of carcinogenic potential. Short-term genotoxic bio-assays using Salmonella, Sister Chromatid Exchange (SCE), and Micronuclei (MN) assays were employed to examine the genotoxic activity of ether extracts of water samples taken from the Songhua River.

[Study on inhibitory effects of c9, t11-conjugated linoleic acid on migration of human gastric carcinoma cell line via cyclooxygenase-2 pathway].

Objective: To study the inhibitory effects of c9, t11-conjugated linoleic acid (c9, t11-CLA) on migration of human gastric carcinoma cell line (SGC-7901) via cyclooxygenase-2 (COX-2) pathway.

Methods: After inhibiting COX-2 activity by 100 micromol/L COX-2 inhibitor NS-398 in SGC-7901 cell, we treated SGC-7901 cells with c9, t11-CLA at a concentration of 200,100, 50, 25 micromol/L for 24 h, respectively. Using reconstituted basement membrane invasion, adhesion, chemotaxis assays, we detected the effect of c9, t11-CLA and COX-2 on the cell migration.

beta-Ionone suppresses mammary carcinogenesis, proliferative activity and induces apoptosis in the mammary gland of the Sprague-Dawley rat.

beta-Ionone demonstrates potent anticancer activity both in vitro and in vivo. We determined tumor incidence and the number of rats bearing tumors as well as cell proliferation and apoptosis in a rat mammary cancer model induced by 7, 12-dimethylbenz[a]anthracene (DMBA). Rats were fed an AIN-76A diet containing beta-ionone (0, 9, 18 or 36 mmol/kg), starting 2 weeks before DMBA administration and continuing for 24 weeks.

Genotoxic activity of organic contamination of the Songhua River in the north-eastern region of the People's Republic of China.

The Songhua River is one of the biggest rivers in China and is the major freshwater source for industry and agriculture, as well as the source of the drinking water for millions of residents living along it. Heavy contamination of the Songhua River is due to domestic sewage and industrial wastewater. Thus, we set out to determine the carcinogenic potential of water samples taken from drinking water source of Harbin city in the Songhua River.

[Inhibitory effect of potential metastasis in SGC-7901 cells induced by beta-ionone].

Objective: To determine the effect of beta-ionone on the potential metastasis of human gastric adenocarcinoma cell line SGC-7901 and the underlying mechanism.

Methods: Using curve of cellular growth, Zymograms, and RT-PCR assays, we analyzed the growth rate, the activities of two types IV collagenase of Matrix met alloproteinase 9 (MMP-9) and MMP-2 and the expression of nm23-H1 gene, tissue inhibitor of met alloproteinase 1 (TIMP-1) and TIMP-2 in SGC-7901 cells which were treated with progressively increasing concentrations (25, 50, 100 and 200 micromol/L) of beta-ionone for 24 h and 48 h.

Results: The growth of SGC-7901 cells was inhibited by beta-ionone.

[Role of cyclooxygenase-2 in inhibition of human gastric adenocarcinoma cell line SGC-7901 by c9, t11-conjugated linoleic acid].

Objective: To study the effects of c9, t11-conjugated linoleic acid (c9, t11-CLA) on the critical enzyme (COX-2) and its product - prostaglandin E2 (PGE2) of linoleic acid metabolism path in human gastric adenocarcinoma cell line (SGC-7901).

Methods: Expression of COX-2 mRNA and protein were measured by reverse transcription polymerase chain reaction (RT-PCR) and Western blot, PGE2 was determined by radioimmunoassay (RIA).

Results: At the concentrations of 25, 50, 100, 200 pmol/L, c9, t11-CLA suppressed the expression of COX-2 mRNA, protein and PGE.

[Effects of conjugated linoleic acid on the expression of critical enzymes of linoleic acid metabolism in tumor cell].

Objectives: To study the effects of c9,t11-conjugated linoleic acid (c9,t11-CLA) on critical enzymes of linoleic acid metabolism in stomach granular cell (SGC-7901).

Methods: SGC-7901 was treated with c9,t11-CLA by 200, 100, 50 or 25 micromol/L for 24 hours. The effects of c9,t11-CLA on the cell proliferation was measured by monotetrazolium and the expression of Delta6-desaturase, Delta5-desaturase, COX-1, COX-2, 5-LOX mRNA were measured by reverse transcription polymerase chain reaction (RT-PCR).

Effects of c9,t11-conjugated linoleic acid on adhesion of human gastric carcinoma cell line SGC-7901.

Aim: To investigate the effect of c9,t11-conjugated linoleic acid (c9,t11-CLA) on the adhesion of human gastric carcinoma cell line (SGC-7901).

Methods: SGC-7901 cells were at first treated with different concentrations (25, 50, 100, 200 micromol/L) of c9,t11-CLA and 1 mL/L ethanol (as a negative control) for 24 h. Using adhesion assay and Western blot, we investigated the ability of SGC-7901 cells to adhere to intracellular matrix and examined the expression of E-cadherin (ECD), alpha-catenin, intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in these cells.

[The effects of conjugated linoleic acid on the ability of murine macrophage in killing tumor cells].

Objective: To study the effects of c9,t11-conjugated linoleic acid on the killing ability of macrophage to B16-MB cells in C57 mice and explore its possible mechanism.

Methods: The five levels of CLA was designed as 0, 25, 50, 75, 100 micro mol/L. After macrophage was treated with CLA for 24 h, the killing ability of macrophage on B16-MB cells was evaluated by MTT, The expression of C57 mice macrophage cytokine IL-6, TNF-alpha and iNOS mRNA was detected by RT-PCR.

Apoptosis of human gastric adenocarcinoma cells induced by beta-ionone.

Aim: To investigate the effect of beta-ionone on the growth and apoptosis of gastric adenocarcinoma cell line SGC-7901.

Methods: Using MTT, fluorescence dye (Hoechst-33258), transmission electron microscopy and the TUNEL assay, we examined growth and apoptosis of SGC-7901 cells treated with beta-ionone at various concentrations (i.e.

Inhibition of beta-ionone on SGC-7901 cell proliferation and upregulation of metalloproteinases-1 and -2 expression.

Aim: To observe the effect of beta-ionone on the proliferation of human gastric adenocarcinoma cell line SGC-7901 and the inhibition of metalloproteinase.

Methods: Using growth inhibition, Zymograms assays and reverse transcription-polymerase-chain reaction (RT-PCR), we examined cell growth rates, activities of matrix metalloproteinases-2 (MMP-2) and -9 (MMP-9), and expression of metalloproteinases-1 (TIMP-1) and -2 (TIMP-2) in SGC-7901 cells after the treatment with beta-ionone for 24 h and 48 h, respectively.

Results: beta-ionone had an inhibitory effect on the growth of SGC-7901 cells.

Inhibitory effects of c9, t11-conjugated linoleic acid on invasion of human gastric carcinoma cell line SGC-7901.

Aim: To investigate the effect of c9, t11-conjugated linoleic acid (c9, t11-CLA) on the invasion of human gastric carcinoma cell line and its possible mechanism of preventing metastasis.

Methods: Using reconstituted basement membrane invasion, chemotaxis, adhesion, PAGE substrate zymography and RT-PCR assays, we analyzed the abilities of invasion, direct migration, adhesion of intracellular matrix, as well as the activity of type IV collagenase and expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 mRNA in SGC-7901 cells which were treated with gradually increased concentrations (25, 50, 100 and 200 micromol/L) of c9, t11-CLA for 24 h.

Results: At the concentrations of 200 micromol/L, 100 micromol/L and 50 micromol/L, c9,t11-CLA suppressed the invasion of SGC-7901 cells into the reconstituted basement membrane by 53.

[The effects of conjugated linoleic acid on the expression of invasiveness and metastasis-associated gene of human gastric carcinoma cell line].

Objectives: To study the effects of c9,t11-conjugated linoleic acid (c9,t11-CLA) on invasive ability of human gastric carcinoma cell line (SGC-7901) and to explore its possible mechanism.

Methods: Reconstituted basement membrane invasion assay was used to evaluate invasive ability of cancer cells. Expression of TIMP-1, TIMP-2 and nm23-H(1) mRNA was measured by reverse transcription polymerase chain reaction (RT-PCR) in SGC-7901 cells.

Inhibition of conjugated linoleic acid on mouse forestomach neoplasia induced by benzo (a) pyrene and chemopreventive mechanisms.

Aim: To explore the inhibition of conjugated linoleic acid isomers in different purity (75 % purity c9,t11-, 98 % purity c9,t11- and 98 % purity t10,c12-CLA) on the formation of forestomach neoplasm and chemopreventive mechanisms.

Methods: Forestomach neoplasm model induced by B(a)P in KunMing mice was established. The numbers of tumor and diameter of each tumor in forestomach were counted; the mice plasma malondialdehyde (MDA) were measured by TBARS assay; TUNEL assay was used to analyze the apoptosis in forestomach neoplasia and the expression of MEK-1, ERK-1, MKP-1 protein in forestomach neoplasm were studied by Western Blotting assay.

Effect of apoptosis on gastric adenocarcinoma cell line SGC-7901 induced by cis-9, trans-11-conjugated linoleic acid.

Aim: To determine the effect of apoptosis on gastric cancer cells (SGC-7901) induced by cis-9, trans-11-conjugated linoleic acid (c9, t11-CLA) and its possible mechanism in the inhibition of cancer cells growth.

Methods: Using cell culture, flow cytometery and immunocytochemical techniques, we examined the cell growth, frequency of apoptosis and distribution of cell cycle, expression of ki67, bcl-2, Fas, and c-myc of SGC-7901 cells which were treated with various c9, t11-CLA concentrations (25,50,100 and 200 micromol x L(-1)) of c9, t11-CLA for 24 h and 48 h, with a negative control (0.1 % ethanol).

Effects ofcis-9,trans-11-conjugated linoleic acid on cancer cell cycle.

Objectives: To determine the effect of cis-9, trans-11-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and its possible mechanism of inhibition cancer growth.

Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B(1), D(1), p16(ink4a) and p21(cip/wafl) of MCF-7 cells which were treated with various c9, t11-CLA concentrations (25 mM, 50 mM, 100 mM and 200 mM) of c9, t11-CLA for 24 and 48 h, with negative controls (0.1% ethanol).