• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.94-94
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• 2002

Lactadherin (formerly known as BA46), a major glycoprotein of the human milk fat globule membrane, is abundant in human breast milk and breast carcinomas and may prevent symptomatic rotavirus infections. In this study, under the control of mouse whey acidic protein (WAP) promoter, the expression pattern of lactadherin (Ltd) in lactogenic hormone-dependent mouse mammary epithelial cell line HC11 were tested. pLNWLtd construct containing 2.4 kilobases of the WAP promoter and 1.5 kilobases of human lactadherin gene was stably transfered into HC11 cells using retroviral vector system. Integration and expression level of the transgene was estimated using PCR and RT-PCR, respectively. Prominent induction of Ltd gene under the WAS promoter was accomplished in the presence of insulin, hydrocortisone and prolactin, while induction with insulin alone resulted in lower expression. Our results demonstrate that the expression of the transgene is increased by synergistic effect of several lactogenic hormones, including insulin, hydrocortisone, and prolactin.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.11a
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• pp.145-145
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• 2002

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.145-145
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• 2002

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a prototype and the most potent chemical of the polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (dioxins). A variety of studies on the toxic effects of dioxin and related compounds have been conducted internationally since 1990.(omitted)

• BMB Reports
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• v.28 no.1
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• pp.57-61
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• 1995

The expression of a recombinant human lactoferrin is reported in mouse HC11 mammary epithelial cells. Expression of human lactoferrin (hLF) was achieved by placing its cDNA under the control of the bovine ${\beta}$-casein gene. To improve the hLF expression level in a cell culture system, two artificial introns were also introduced to construct expression vectors. One intron was a hybrid-splice signal consisting of bovine ${\beta}$-casein intron 1 and rabbit ${\beta}$-globin intron II. The other intron was a DNA fragment spanning intron 8 of the bovine ${\beta}$-casein gene. The hybrid intron moderately elevated hLF expression, whereas intron 8 alone did not express any detectable amount of hLF as judged by Northem and Western blot analyses. When the two introns were used together they contributed to a synergistic elevation of hLF expression. These data indicate that artificial introns on both sides of the hLF cDNA were necessary to increase expression of cDNA.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.59-59
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• 2001

Interleukin-10 (IL-10) is known as a regulator of inflammation and pathogenesis in mammalian organs, but its precise role is little known in the mammary gland. Our initial experiment showed that IL-10 expression levels in mice decreased at the lactation stage otherwise increased at the involution stage. To reveal the effects of IL-10 on the involution of mammary gland, expression profiles of the apoptosis-related genes were examined in transgenic mice expressing human IL-10 as well as in knock-out mice (IL-10-/-). Mild inflammatory legions by lymphocytes were observed in the mammary glands of transgenic lines at the lactation stage. The expression of TRAIL (Tumor necrosis factor-Related Apoptosis-Inducing Ligand) among the apoptosis-related genes was highly elevated in the transgenic mice while others were not significantly changed. Furthermore, TRAIL was down regulated by four fold in the IL-10-/- mice at the involution stage. The expression of DR4 was elevated at the involution stage of normal mice. DR4 was detected in the milk of transgenic mice but absent in that of normal mice. Our results proposed that the elevated IL-10 at the involution stage recruit lymphocytes and induce TRAIL and DR4 genes, therefore, lead to enter involution stage of mammary glands.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.17-17
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• 2003

The milk of transgenic animals may provide an attractive vehicle for large-scale production of hEPO. Since glycosylation is cell type specific, recombinant human EPO (rhEPO) produced in different host cells contain different patterns of oligosaccharides, which could affect the biological functions. However, there have been no reports on the characteristics of rhEPO derived from milk of transgenic animals. To address this objective, several transgenic mice by using pWAPhEPO and/or pBC1hEPO expression vector were produced. However, 2 lines of pWAPhEPO founder female mouse died during late gestational day (day 18) before offspring could be obtained. They showed a severe splenomegaly, Unlike those of pWAPhEPO, mammary gland epithelial cells from biopsies of lactating pBC1hEPO transgenic mice had marked immunoreactivity to EPO and any activity was not detected in other tissues. The expression level of rhEPO is about 0.7% of mammary gland cellular total soluble proteins and an amount of 300~500 mg/L rhEPO is secreted into milk. Furthermore, the pBC1hEPO transgenic mice transmitted this character to their progeny in mendelian manner. In order to determine the extent of glycosylation variation, N-linked oligosaccharide structures present in the milk-derived rhEPO were characterized. Most of milk-derived rhEPO is fully glycosylated. the biological activity of milk-derived rhEPO was comparable to that of purified CHO-derived rhEPO, and milk-derived rhEPO showed relatively stable after freezing and thawing. Taken together, the results illustrate the potential of transgenic animals in the large-scale production of biopharmaceuticals.

• Environmental Mutagens and Carcinogens
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• v.19 no.1
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• pp.56-62
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• 1999

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) has been considered to be as one of major antioxidants present in grapes responsible for beneficial effects of red wine consumption on coronary heart disease. This triphenolic stilbene has been suggested as a potential cancer chemopreventive agent based on its striking inhiitory effects on diverse cellular events associated with tumor initiation, promotion, and progression. The compound has strong antioxidative and anti-inflammatory activities which amy contribute to its chemopreventive/chemoprotective properties. In the present work, we have found that resveratrol reduces viability and DNA synthesis capability of cultured human promyelocytic leukemia (HL-60) cells. Likewise, the viability of human breast cancer cell line, MCF-7 was reduced by resveratrol treatment. The growth inhibitory and antiproliferative properties of resveratrol appear to be associated with its induction of apoptotic cell death as determined by morphological and ultrastructural changes, agarose gel electrphoretic analysis of internucleosomal DNA fragmentation, and in situ terminal end-labeling of fragmented DNA (TUNEL). This compound also inhibited the phorbol ester-induced expression of cyclooxygenase-2 (COX-2) protein in immortalized human mammary epithelial MCF-10A cells. These results suggest that resveratrol has the promising cancer therapeutic/chemopreventive potential.

• Journal of Life Science
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• v.31 no.2
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• pp.248-255
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• 2021

Mammary gland tumors are one of the most common cancers in female dogs, and there are various types of cells depending on the tumor type. Complex carcinoma consists of a combination of luminal epithelial and myoepithelial cells with intra-tumoral heterogeneity. However, the origins of these tumor cells and their effects on the malignancies of tumors have not been identified. Recently, it has been reported that cancer stem cells, identified in several types of human tumors, are involved in tumor heterogeneity and may also contribute to malignancies such as tumor recurrence and metastasis. Interestingly, cancer stem cells share several abilities of self-renewal and cell differentiation into multiple types of cancer cells, but they have abnormal genetic mutation and signal transduction pathways to regulate the maintenance of stem cell characters. Moreover, it is known that these cell populations contribute to cell metastasis as well as cell resistance against chemo- and radio-therapeutics that promote tumor recurrence. The existence of cancer stem cells might explain the intra-tumoral heterogeneity and cancer aggressiveness during tumorigenesis in canine mammary gland tumors. This review summarizes the characteristics and types of canine mammary gland tumors, the definition of tumor stem cells, methods of isolation, and clinical significance.

• Biomedical Science Letters
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• v.11 no.2
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• pp.175-183
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• 2005

The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

• Genomics & Informatics
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• v.21 no.2
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• pp.19.1-19.13
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• 2023

Liver cancer, particularly hepatocellular carcinoma (HCC), poses a significant global threat to human lives. To advance the development of innovative diagnostic and treatment approaches, it is essential to examine the hidden features of HCC, particularly its 3D genome architecture, which is not well understood. In this study, we investigated the 3D genome organization of four HCC cell lines-Hep3B, Huh1, Huh7, and SNU449-using in situ Hi-C and assay for transposase-accessible chromatin sequencing. Our findings revealed that HCC cell lines had more long-range interactions, both intra-and interchromosomal, compared to human mammary epithelial cells (HMECs). Unexpectedly, HCC cell lines displayed cell line-specific compartmental modifications at the megabase (Mb) scale, which could potentially be leveraged in determining HCC subtypes. At the sub-Mb scale, we observed decreases in intra-TAD (topologically associated domain) interactions and chromatin loops in HCC cell lines compared to HMECs. Lastly, we discovered a correlation between gene expression and the 3D chromatin architecture of SLC8A1, which encodes a sodium-calcium antiporter whose modulation is known to induce apoptosis by comparison between HCC cell lines and HMECs. Our findings suggest that HCC cell lines have a distinct 3D genome organization that is different from those of normal and other cancer cells based on the analysis of compartments, TADs, and chromatin loops. Overall, we take this as evidence that genome organization plays a crucial role in cancer phenotype determination. Further exploration of epigenetics in HCC will help us to better understand specific gene regulation mechanisms and uncover novel targets for cancer treatment.