Publications by authors named "Min Ji Bak"

K vitamins are well known as essential cofactors for hepatic γ-carboxylation of coagulation factors, but their potential role in chronic diseases including cancer is understudied. K2, the most abundant form of vitamin K in tissues, exerts anti-cancer effects via diverse mechanisms which are not completely understood. Our studies were prompted by previous work demonstrating that the K2 precursor menadione synergized with 1,25 dihydroxyvitamin D3 (1,25(OH)D) to inhibit growth of MCF7 luminal breast cancer cells.

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Phylloquinone (vitamin K1) and menaquinones (vitamin K2 family) are essential for post-translational γ-carboxylation of a small number of proteins, including clotting factors. These modified proteins have now been implicated in diverse physiological and pathological processes including cancer. Vitamin K intake has been inversely associated with cancer incidence and mortality in observational studies.

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Ductal carcinoma (DCIS), which accounts for one out of every five new breast cancer diagnoses, will progress to potentially lethal invasive ductal carcinoma (IDC) in about 50% of cases. Vitamin D compounds have been shown to inhibit progression to IDC in the MCF10DCIS model. This inhibition appears to involve a reduction in the cancer stem cell-like population in MCF10DCIS tumors.

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Our previous studies have demonstrated antioxidant and cytoprotective properties of red ginseng oil (RGO). However, the role of RGO in models of intestinal inflammation has not been elucidated. In this study, we evaluated the chemopreventive effect of RGO in a mouse model of azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis and explored its underlying mechanisms.

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Estrogen plays an important role in breast cancer development. While the mechanism of the estrogen effects is not fully elucidated, one possible route is by increasing the stem cell-like properties in the tumors. Tocopherols are known to reduce breast cancer development and progression.

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Despite experimental evidence elucidating the antitumor activities of tocopherols, clinical trials with α-tocopherol (α-T) have failed to demonstrate its beneficial effects in cancer prevention. This study compared the chemopreventive efficacy of individual tocopherols (α-, δ-, and γ-T) and a γ-T-rich tocopherol mixture (γ-TmT) in the August-Copenhagen Irish (ACI) rat model of estrogen-mediated mammary cancer. Female ACI rats receiving 17β-estradiol (E2) implants were administered with 0.

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Hair loss (alopecia) is a universal problem for numerous people in the world. The present study was conducted to investigate the effects of red ginseng oil (RGO) and its major components on hair re-growth using testosterone (TES)-induced delay of anagen entry in C57BL/6 mice and their mechanisms of action. Seven-week-old C57BL/6 mice were daily treated with TES for 1 h prior to topical application of 10% RGO, 1% linoleic acid (LA), 1% β-sitosterol (SITOS), or 1% bicyclo(10.

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Estrogens have been implicated as complete carcinogens for breast and other tissues through mechanisms involving increased cell proliferation, oxidative stress, and DNA damage. Because of their potent antioxidant activity and other effects, tocopherols have been shown to exert antitumor activities in various cancers. However, limited information is available on the effect of different forms of tocopherols in estrogen-mediated breast cancer.

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Triple-negative breast cancer is one of the least responsive breast cancer subtypes to available targeted therapies due to the absence of hormonal receptors, aggressive phenotypes, and the high rate of relapse. Early breast cancer prevention may therefore play an important role in delaying the progression of triple-negative breast cancer. Cancer stem cells are a subset of cancer cells that are thought to be responsible for tumor progression, treatment resistance, and metastasis.

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Background: The induction of cellular defensive genes such as phase II detoxifying and antioxidant enzymes is a highly effective strategy for protection against carcinogenesis as well as slowing cancer development. Transcription factor Nrf2 (nuclear factor E2-related factor 2) is responsible for activation of phase II enzymes induced by natural chemopreventive compounds.

Methods: Red ginseng oil (RGO) was extracted using a supercritical CO extraction system and chemical profile of RGO was investigated by GC/MS.

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In the present study, we characterized the antioxidant and hepatoprotective mechanisms underlying of wild grape seed procyanidins (WGP) against oxidative stress damage in ethanol-treated HepG2 cell and Sprague-Dawley (SD)-rat models. In HepG2 cells, WGP not only diminished the ethanol (EtOH, 100 mM)-induced reactive oxygen species (ROS) formation and cytochrome P450 2E1 (CYP2E1) expression, but also renovated both the activity and expression of antioxidant enzymes including catalase, superoxide dismutase, and glutathione peroxidase. Additionally, to investigate the hepatoprotective effect of WGP, rats were orally administered 10 or 50 mg/kg WGP once daily for seven days prior to the single oral administration of EtOH (6 g/kg).

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Estrogen receptor (ER)-positive breast cancer, including luminal-A and -B, is the most common type of breast cancer. Extended exposure to estrogen is associated with an increased risk of breast cancer. Both ER-dependent and ER-independent mechanisms have been implicated in estrogen-mediated carcinogenesis.

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This study evaluated the anticancer activity and mechanism of action of a γ-tocopherol-rich tocopherol mixture, γ-TmT, in two different animal models of estrogen-induced breast cancer. The chemopreventive effect of γ-TmT at early (6 weeks), intermediate (18 weeks), and late (31 weeks) stages of mammary tumorigenesis was determined using the August-Copenhagen Irish rat model. Female rats receiving 17β-estradiol (E2) implants were administered with different doses (0%, 0.

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Fermented black ginseng (FBG) is prepared by repeated steaming and drying processes with fresh ginseng followed by fermentation with Saccharomyces cerevisiae. It has recently been shown to have several bioactivities. FBG contains crude saponin (1,440 µg/ml), ginsenoside Rg2 (2.

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Unlabelled: Procyanidins, polymeric flavan-3-ols, are known to possess antioxidant, antiatherogenic, and anticarcinogenic properties. In the present study, we investigated the role of almond (Prunus amygdalus) skin procyanidins (ASP) in regulating the protein expression of phase II detoxifying and antioxidant enzymes in HepG2 cells and acetaminophen (APAP)-treated hepatotoxic mice. Treatments of ASP significantly induced the expression of phase II enzymes including

Nad(p)h: quinoneoxidoreductase 1, catalase, glutathione peroxidase, and superoxide dismutase in the cells and mice.

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The single oral administration of red ginseng oil (5000 mg/kg) to Sprague-Dawley rats induced no changes in behavioral patterns, clinical signs, and body weight, and hepatotoxicity parameters such as aspartate aminotransferase and alanine aminotransferase for 14 d. Therefore, these results suggest that the red ginseng oil is safe and nontoxic acutely.

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In the present study, the anti-inflammatory effect and underlying mechanisms of wild grape seeds procyanidins (WGP) were examined using lipopolysaccharide- (LPS-) stimulated RAW 264.7 cells. We used nitric oxide (NO) and prostaglandin E2 (PGE2) and reactive oxygen species (ROS) assays to examine inhibitory effect of WGP and further investigated the mechanisms of WGP suppressed LPS-mediated genes and upstream expression by Western blot and confocal microscopy analysis.

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In this study, we investigated the anti-inflammatory effects of red ginseng marc oil (RMO) in the RAW 264.7 macrophage cell line. RMO was prepared by a supercritical CO(2) extraction of waste product generated after hot water extraction of red ginseng.

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The rhizome of ginger (Zingiber officinale Roscoe) is known to have several bioactive compounds including gingerols and shogaols which possess beneficial health properties such as anti-inflammatory and chemopreventive effects. Based on recent observations that 6-shogaol may have more potent bioactivity than 6-gingerol, we obtained a 6-shogaol-rich extract from ginger and examined its effects on the nuclear factor E2-related factor2 (Nrf2)/antioxidant response element (ARE) pathway in vitro and in vivo. 6-Shogaol-rich extract was produced by extracting ginger powder with 95% ethanol at 80 °C after drying at 80 °C (GEE8080).

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The aim of this study was to evaluate the antioxidant mechanisms of red ginseng essential oil (REO) in cells as well as in an animal model. REO was prepared by a supercritical CO(2) extraction of waste-products generated after hot water extraction of red ginseng. In HepG2 cells, REO diminished the H(2)O(2)-mediated oxidative stress and also restored both the activity and expression of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase.

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Procyanidins, polymers of flavan-3-ol units, have been reported to exhibit many beneficial health effects such as antioxidant and anti-carcinogenic effects. In this study, we investigated the cancer chemopreventive properties of procyanidins from wild grape (Vitis amurensis) seeds in particular their roles in inducing phase II detoxifying/antioxidant enzymes as well as in modulating the upstream kinases. Ethanolic extract of V.

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Cedrela sinensis has been widely used in traditional Oriental medicine to treat a variety of diseases. However, little is known about the cellular actions by which this plant mediates its antioxidant effects. In this study, activity-guided fractionations of C.

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