• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.457-473
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• 2002

The purposes of this study is to evaluate the combination effects of TGF-${\beta}_1$ and PDGF-BB on the periodontal ligament cells to use as a regeneration promoting agent of periodontal tissue. Human periodontal ligament cells were prepared from the first premolar tooth extracted for the orthodontic treatment and were cultured in DMEM/100% FBS at the $37^{\circ}C$, 5% $CO_2$ incubator. Authors measured the DNA synthesis, total protein, collagen and noncollagenous protein synthesis according to the concentration of TGF-${\beta}_1$,(1,5ng/ml) and PDGF-BB (1,10 ng/ml) in combination. To explore further this delayed effect of TGF-${\beta}_1$, we preincubated human periodontal ligament cells with TGF-${\beta}_1$ for 4 or 24 hours before PDGF-BB stimulation. The results were as follows: The DNA synthetic activity was increased dose dependently by TGF-${\beta}_1$, PDGF-BB. The combination of TGF-${\beta}_1$ and PDGF-BB consistently enhanced the DNA synthetic activity to PDGF-BB alone. The ability of TGF-${\beta}_1$ to enhance DNA synthetic activity in PDGF-BB treated periodontal ligament cells was dose dependent. The maximum mitogenic effect was at the 5ng/ml of TGF-${\beta}_1$ and l0ng/ml of PDGF-BB. Preincubation of cell with TGF-${\beta}_1$ resulted in significantly greater response to PDGF-BB at all TGF-${\beta}_1$ concentration studied, and may be useful for clinical application in periodontal regenerative procedures. The total protein, collagen and noncollagen synthesis was increased dose pendently by TGF-${\beta}_1$, PDGF-BB. The % of collagen was slightly decreased according to the concentration of TGF-${\beta}_1$, PDGF-BB. The effect of TGF-${\beta}_1$, PDGF-BB were not specific for collagen synthesis since it also increased noncollagenous protein synthesis. This study demonstrates that PDGF-BB is major mitogens for human periodontal ligament cells in vitro, and supports a role for TGF-${\beta}_1$ as a regulation of the mitogenic and total protein formation to PDGF-BB in these cells.

• 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.

• BMB Reports
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• v.38 no.1
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• pp.9-16
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• 2005

Transforming Growth Factor (TGF)-$\beta$ family, including TGF-$\beta$, bone morphorgenic protein (BMP), and activn, plays an important role in essential cellular functions such as proliferation, differentiation, apoptosis, tissue remodeling, angiognesis, immune responses, and cell adhesions. TGF-$\beta$ predominantly transmits the signals through serine/threonine receptor kinases and cytoplasmic proteins called Smads. Since the discovery of TGF-$\beta$ in the early 1980s, the dysregulation of TGF-$\beta$/Smad signaling has been implicated in the pathogenesis of human diseases. Among signal transducers in TGF-$\beta$/Smad signaling, inhibitory Smads (I-Smads), Smad6 and Smad7, act as major negative regulators forming autoinhibitory feedback loops and mediate the cross-talking with other signaling pathways. Expressions of I-Smads are mainly regulated on the transcriptional levels and post-translational protein degradations and their intracellular levels are tightly controlled to maintain the homeostatic balances. However, abnormal levels of I-Smads in the pathological conditions elicit the altered TGF-$\beta$ signaling in cells, eventually causing TGF-$\beta$-related human diseases. Thus, exploring the molecular mechanisms about the regulations of I-Smads may provide the therapeutic clues for human diseases induced by the abnormal TGF-$\beta$ signaling.

• Archives of Pharmacal Research
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• v.22 no.1
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• pp.1-8
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• 1999

Transforming growth factor-$\beta$ (TGF-$\beta$) is the prototypical multifunctional cytokine, participating in the regulation of vital cellular activities such as proliferation and differentiations as well as a number of basic physiological functions. The effects of TGF-$\beta$ are critically dependent on the expression and distribution of a family of TGF-$\beta$ receptors, the TGF-$\beta$ types I, II, and III. It is now known that a wide variety of human pathology can be caused by aberrant expression and function of these receptors. the coding sequence of the type II receptor (RII) appears to render it uniquely susceptible to DNA replication errors in the course of normal cell division. By virtue of its key role in the regulation of cell proliferation, TGF-$\beta$ RII should be considered as a tumor suppressor gene. High levels of mutation in the TGF-$\beta$ RII gene have been observed in a wide range of primarily epithelial malignancies, including colon and gastric cancer. It appears likely that mutation of the TGF-$\beta$ RII gene may be a very critical step in the pathway of carcinogenesis.

• Toxicological Research
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• v.27 no.4
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• pp.253-259
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• 2011

Transforming growth factor ${\beta}$ (TGF-${\beta}$) is involved in cellular processes including growth, differentiation, apoptosis, migration, and homeostasis. Generally, TGF-${\beta}$ is the inhibitor of cell cycle progression and plays a role in enhancing the antagonistic effects of many growth factors. Unlike the antiproliferative effect of TGF-${\beta}$, E2, an endogeneous estrogen, is stimulating cell proliferation in the estrogen-dependent organs, which are mediated via the estrogen receptors, $ER{\alpha}$ and $ER{\beta}$, and may be considered as a critical risk factor in tumorigenesis of hormone-responsive cancers. Previous researches reported the cross-talk between estrogen/$ER{\alpha}$ and TGF-${\beta}$ pathway. Especially, based on the E2-mediated inhibition of TGF-${\beta}$ signaling, we examined the inhibition effect of 4-tert-octylphenol (OP) and 4-nonylphenol (NP), which are well known xenoestrogens in endocrine disrupting chemicals (EDCs), on TGF-${\beta}$ signaling via semi-quantitative reverse-transcription PCR. The treatment of E2, OP, or NP resulted in the downregulation of TGF-${\beta}$ receptor2 (TGF-${\beta}$ R2) in TGF-${\beta}$ signaling pathway. However, the expression level of TGF-${\beta}1$ and TGF-${\beta}$ receptor1 (TGF-${\beta}$ R1) genes was not altered. On the other hand, E2, OP, or NP upregulated the expression of a cell-cycle regulating gene, c-myc, which is a oncogene and a downstream target gene of TGF-${\beta}$ signaling pathway. As a result of downregulation of TGF-${\beta}$ R2 and the upregulation of c-myc, E2, OP, or NP increased cell proliferation of BG-1 ovarian cancer cells. Taken together, these results suggest that E2 and these two EDCs may mediate cancer cell proliferation by inhibiting TGF-${\beta}$ signaling via the downregulation of TGF-${\beta}$ R2 and the upregulation of c-myc oncogene. In addition, it can be inferred that these EDCs have the possibility of tumorigenesis in estrogen-responsive organs by certainly representing estrogenic effect in inhibiting TGF-${\beta}$ signaling.

• KSBB Journal
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• v.14 no.1
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• pp.9-16
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• 1999

Transforming growth factor $\beta$1(TGF-$\beta$1) has potentials to be used as a new therapeutic agent. However, studies with TGF-$\beta$ were hindered by its high cost. In this study, we developed an improved method to purify TGF-$\beta$1 from human platelets, for which four purification steps were used: platelet extraction, gel filtration, cation exchange chromatography, and reverse phase high performance liquid chromatography. After a final step of purification, a pure protein with a molecular weight of 25,000 corresponding to the commercially available TGF-$\beta$1 was obtained, which were confirmed by silver staining and Western blotting after SDS-polyacrylamide gel electrophoresis (SDS-PAGE). It was confirmed by the inhibitory effects of TGF-$\beta$1 on a mink lung epithelial cell line that the purified TGF-$\beta$1 had its biological activity, whose activity is slightly higher than that of the commercially available TGF-$\beta$1. About 3.7$\mug of the purified TGF-$\beta$1 was obtained from 10 units of concentrated human platelets, the final yield of which is about 21%.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.193-207
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• 1990

Transforming growth factor ${\beta}(TGF-{\beta})$ is a multifunctional polypeptide with diverse effects on the proliferation, differentiation and other functions in many cell types. $TGF-{\beta}$ is highly abundant in bone matrix and induces divergent responses in many aspects of bone cell metabolism . Several lines of investigation indicate that matrix-associated $TGF-{\beta}$ is the products of bone cells themselves. However, exact bone cell type reponsible for the production of $TGF-{\beta}$ is still in controversy, The present study was undertaken to determine the cellular origin of matrix-associated $TGF-{\beta}$ and to assess how different bone cells respond to $TGF-{\beta}$. As a prerequisite for this, 5 bone cell populations of distinct phenotype were isolated from fetal calvaria with sequential enzyme digestion protocol and biochemical characterization. Calvarial cell populations released in early stage showed fibroblastic features whereas populations relesed later was enriched with osteoblast-like cell as judged by their acid and alkaline phosphatase activities, cAMP responsiveness to parathyroid hormone, calcitonin and prostaglandin $E_2$ and collagen synthesis rate. By polyacylamide gel and immunoblot analysis of bone and calvarial cell extracts, presence of $TGF-{\beta}$ in bone tissues and production of $TGF-{\beta}$ by bone cells were confirmed again. Subsequent analysis of calvarial cell extracts prepared as individual population revealed that all calvarial cell populations synthesize $TGF-{\beta}$. Exogenously added $TGF-{\beta}$ induced biphasic response upon bone cell proliferation under serum-free condition. In osteoblastic cell populations, it was stimulatory whereas inhibitory in fibroblastic cell populations. In contrast, collagen and noncollagen protein synthesis of all calvarial cell populations were stimulated by $TGF-{\beta}$. Enhancement of protein synthesis was found to be more general rather than specific for collagen synthesis. In addition, effects of $TGF-{\beta}$ on protein synthesis were independent to its effects on cell proliferation. In summary, production of $TGF-{\beta}$ by bone cells and differential actions on various cell populations observed in this study suggest that $TGF-{\beta}$ may play an important role in the regulation of bone metabolism by modulating the specific cellular functions in autocrine and paracrine fashion.

• Journal of Microbiology
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• v.35 no.4
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• pp.341-346
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• 1997

In order to express recombinant porcine TGF-${\beta}1$ protein in a baculovirus expression system the entire TGF-${\beta}1$gene containing extra amino acids at the N terminus was cloned into pFBa and pFBb of the Bac-To-$Bac^{TM}$ baculovirus expression system. One of the clones contained 106 extra amino acids and was designated pFBa-106 TGF-${\beta}1$, and the other had 28 extra amino acids and was designated pFBb-28 TGF-${\beta}1$. The orientation of the gene was identified with restriction enzyme mapping and PCR with internal TGF-${\beta}1$ primers. Sf-9 cells were infected at a m.o.i. of 10 by the recombinant viruses generated from the two expected sizes of 55 kD and 46.4kD. these precursor forms of TGF-${\beta}1$ with a polyclonal antibody against human TGF-${\beta}1$. No mature form of TGF-${\beta}1$ protein was detected on SDS gels and an immunoblot indicated that TGF-${\beta}1$ precursor is not properlu processed in insect cells.

• The Journal of Korean Medicine
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• v.24 no.2
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• pp.1-11
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• 2003

Objectives : The aim of this study was to characterize the effect of Injinchunggan-tang on $TGF-{\beta}1-induced$ hepatic fibrosis. Methods : mRNA and protein expression levels of $TGF-{\beta}1$ in Injinchunggan-tang-treated HepG2 cells were compared to untreated cells using quantitative RT-PCR and ELISA assay, respectively. mRNA expression levels of the TGF-1 pathway genes (TR-1, TR-II, Smad2, Smad3, Smad4, and PAI-1) and fibrosis-associated genes (CTGF, fibronectin, and collagen type 1) were evaluated by quantitative RT-PCR. The effect of Injinchunggan-tang on cell proliferation of T3891 human fibroblast was evaluated using [$^3H$]thymidine incorporation assay. Results : Expression of $TGF-{\beta}1$ mRNA and protein was inhibited by Injinchunggan-tang in a dose- and time-dependent manner. Whereas $TGF-{\beta}1-mediated$ induction of PAI-1 was suppressed by Injinchunggan-tang, expression of the $TGF-{\beta}1$ pathway genes such as TR-1, TR-II, Smad2, Smad3, and Smad4 was not affected by Injinchunggan-tang treatment. Injinchunggan-tang was found to inhibit $TGF-{\beta}1-induced$ cell proliferation of T3891 human fibroblast, and also abrogated $TGF-{\beta}1-mediated$ transcriptional up-regulation of CTGF, fibronectin, and collagen type I. Conclusions : This study strongly suggests that the liver cirrhosis-suppressive activity of Injinchunggan-tang may be derived at least in part from its inhibitory effect on $TGF-{\beta}1$ functions, such as blockade of $TGF-{\beta}1$ stimulation of fibroblast cell proliferation and fibrosis-related gene expression as well as expression of $TGF-{\beta}1$ itself.

• Biomedical Science Letters
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• v.5 no.2
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• pp.181-190
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• 1999

To evaluate the usefulness of transforming growth factor-$\beta$1 (TGF-$\beta$1) as a new tumor marker, we determined the plasma TGF-$\beta$1 levels using sandwich ELISA assay in cancer patients. Patients with three most common adult cancers in Korea (stomach, liver and breast cancer) and children's cancers (leukemia and two kinds of solid tumor) were enrolled for the study. Furthermore, 39 individuals were subjected to age and sex-stratified plasma TGF-$\beta$1 analysis. No statistical difference was demonstrated with respect to age or sex. The mean plasma TGF-$\beta$1 level (16.0 ng/ ml) of stomach cancer patients was significantly higher than that (8.3 ng/ml) of controls. However, there was no difference among the mean plasma TGF-$\beta$1 levels of liver, breast cancer patients and controls. Seven of 16 patients (43.7%) with stomach cancer, one of 8 (12.5%) with liver cancer, and one of 7 (14.3%) with breast cancer showed higher TGF-$\beta$1 levels compared to controls. Plasma TGF-$\beta$1 concentrations of five leukemic children remained in the normal range regardless of the remission state. In contrast, initial high TGF-$\beta$1 levels from two children with solid tumors returned to normal range on surgical resection of tumors. From the above results, we could conclude that plasma TGF-$\beta$1 levels of apparently healthy individuals seem to be rather constant irrespective of difference in age or sex, and the plasma TGF-$\beta$1 has the limited value as a screening test for the diagnosis of aforementioned adult cancers because of its low sensitivity. Finally, additional studies need to be pursed for the large number of stomach cancer and pediatric solid tumor patients in order to reach a secure conclusion on the usefulness of plasma TGF-$\beta$1 as a tumor marker in these patients.