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Featured researches published by Eunyoung Ko.


Phytomedicine | 2010

The alkaloid Berberine inhibits the growth of anoikis-resistant MCF-7 and MDA-MB-231 breast cancer cell lines by inducing cell cycle arrest.

Jong Bin Kim; Jaehoon Yu; Eunyoung Ko; Kyung-Mu Lee; A.K. Song; Soo Young Park; Incheol Shin; Wonshik Han; D-Y Noh

Berberine is a pure phenanthren alkaloid isolated from the roots and bark of herbal plants such as Berberis, Hydrastis canadensis and Coptis chinensis. Berberine has been established to inhibit the growth of breast cancer cells, but its effects on the drug resistance and anoikis-resistance of breast cancer cells have yet to be elucidated. Anoikis, or detachment-induced apoptosis, may prevent cancer progression and metastasis by blocking signals necessary for survival of localized cancer cells. Resistance to anoikis is regarded as a prerequisite for metastasis; however, little is known about the role of berberine in anoikis-resistance. We established anoikis-resistant cells from the breast cancer cell lines MCF-7 and MDA-MB-231 by culturing them on a Poly-Hema substratum. We then investigated the effects of berberine on the growth of these cells. The anoikis-resistant cells had a reduced growth rate and were more invasive than their respective adherent cell lines. The effect of berberine on growth was compared to that of doxorubicine, which is a drug commonly used to treat breast cancer, in both the adherent and anoikis-resistant cell lines. Berberine promoted the growth inhibition of anoikis-resistant cells to a greater extent than doxorubicine treatment. Treatment with berberine-induced cell cycle arrest at G0/G1 in the anoikis-resistant MCF-7 and MDA-MB-231 cells as compared to untreated control cells. In summary, these results revealed that berberine can efficiently inhibit growth by inducing cell cycle arrest in anoikis-resistant MCF-7 and MDA-MB-231 cells. Further analysis of these phenotypes is essential for understanding the effect of berberine on anoikis-resistant breast cancer cells, which would be relevant for the therapeutic targeting of breast cancer metastasis.


Cancer Epidemiology, Biomarkers & Prevention | 2009

Autoantibody to tumor antigen, alpha 2-HS glycoprotein: a novel biomarker of breast cancer screening and diagnosis.

Jae Kyo Yi; Jong Wook Chang; Wonshik Han; Jong Won Lee; Eunyoung Ko; Dong-Hyun Kim; Ji-Yeon Bae; J. Yu; Cheolju Lee; Myeong-Hee Yu; Dong-Young Noh

We sought to identify a new serum biomarker for breast cancer screening and diagnosis using stepwise proteomic analysis of sera from breast cancer patients to detect the presence of autoantibodies that react with urinary protein. Two-dimensional immunoblotting was done for screening autoimmunogenic tumor antigens in the urine of breast cancer patients. Reactive spots were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Among urinary proteins separated by two-dimensional electrophoresis, 13 spots showed strong reactivity with pooled sera from breast cancer patients or control sera. By mass spectrometry, we identified α 2-HS glycoprotein (AHSG) as a tumor antigen. Peripheral blood was obtained from 81 women diagnosed with breast cancer before surgery and 73 female donors without evidence of any malignancy for the individual analysis. In one-dimensional Western blot analysis, AHSG autoantibody was detected in 64 of 81 breast cancer patients (79.1%) and in 7 of 73 controls (9.6%). The sensitivity of this test in breast cancer patients was 79.0%. Our results suggest that AHSG and anti-AHSG autoantibody may be useful serum biomarkers for breast cancer screening and diagnosis. (Cancer Epidemiol Biomarkers Prev 2009;18(5):1357–64)


Planta Medica | 2008

Berberine Diminishes the Side Population and ABCG2 Transporter Expression in MCF-7 Breast Cancer Cells

Jong Bin Kim; Eunyoung Ko; Wonshik Han; Incheol Shin; Seo Young Park; Dong-Young Noh

The plant alkaloid berberine has many biological activities including the ability to induce cell cycle arrest and apoptosis, making it a potentially useful agent for targeting cancer cells. We have analyzed the effects of berberine on MCF-7 breast cancer cells. Berberine was added to MCF-7 cells in culture, and proliferation, side population (SP) cells and expression of ABCG2 were examined. Berberine caused a dose-dependent reduction in proliferation. Hoechst 33,342 dye staining and FACS analysis revealed that berberine treatment caused a decrease in SP cells relative to untreated controls. In addition, berberine treatment was associated with a decrease in expression of ABCG2 relative to untreated controls. These results indicate that the growth inhibitory effects of berberine treatment on MCF-7 cells may be partly via effects on SP and ABCG2 expression. Further work is warranted to explore whether berberine may be a novel therapeutic drug useful for targeting breast cancer stem cells.


Journal of Surgical Oncology | 2008

Sonographic lesion size of ductal carcinoma in situ as a preoperative predictor for the presence of an invasive focus.

Jong Won Lee; Wonshik Han; Eunyoung Ko; Jihyoung Cho; Eun-Kyu Kim; So-Youn Jung; Nariya Cho; Woo Kyung Moon; In-Ae Park; Dong-Young Noh

To investigate the preoperative factors associated with upstage to invasive cancer in patients with core needle biopsy (CNB) diagnosis of ductal carcinoma in situ (DCIS) by ultrasound guidance alone.


International Journal of Cancer | 2008

Genomic copy number alterations as predictive markers of systemic recurrence in breast cancer

Ki-Tae Hwang; Wonshik Han; Jihyoung Cho; Jong Won Lee; Eunyoung Ko; Eun Kyu Kim; So-Youn Jung; Eun-Mi Jeong; Ji-Yeon Bae; Jason Jongho Kang; Song-Ju Yang; Sung-Won Kim; Dong-Young Noh

We tried to establish models that predict systemic recurrence in breast cancer by selecting marker clones with DNA copy number alterations (CNAs) using an array comparative genomic hybridization (CGH). Array CGH containing 4,044 human bacterial artificial chromosome clones was used to assess CNAs in 62 primary breast cancer tissues from 31 patients with systemic recurrence within 5 years after surgery and clinicopathologically well matched 31 patients who had no evidence of disease for at least 5years. Fourteen significant clones (11 clones showing gain and 3 showing loss) were identified by systemic recurrence‐free survival (SRFS) analysis and 23 significant clones (17 clones showing gain and 6 showing loss) identified by χ2 test and FDR test were selected as predictive markers of systemic breast cancer recurrence. The significant CNAs were found in the chromosomal regions of 5p15.33, 11q13.3, 15q26.3, 17q25.3, 18q23 and 21q22.3 with gain and 9p12, 11q24.1 and 14q32.33 with loss. We devised 2 prediction models for the systemic recurrence of breast cancer based on the 14 clones and the 23 clones, respectively. The survivals of the patients were significantly separated according to the scores from each model at the optimal cut off values in SRFS and overall survival analysis. We found candidate clones and genes of which CNAs were significantly associated with systemic recurrence of breast cancer. The devised prediction models with these clones were effective at differentiating the recurrence and nonrecurrence.


Planta Medica | 2008

Berberine inhibits growth of the breast cancer cell lines MCF-7 and MDA-MB-231.

Jong Bin Kim; Kyung-Min Lee; Eunyoung Ko; Wonshik Han; Jeong Eon Lee; Incheol Shin; Ji-Yeon Bae; Sangmin Kim; Dong-Young Noh

The effects of berberine on the behavior of breast tumors have not yet been established. To determine whether this compound is useful in the treatment of breast cancer, we analyzed the impact of berberine on the human breast cancer cell lines MCF-7 and MDA-MB-231 cells. Berberine was added to proliferating MCF-7 and MDA-MB-231 cells in culture. Following treatment, changes in cell growth characteristics such as proliferation, cell cycle duration, and the degree of apoptosis were assayed. Following berberine treatment, a time-dependent reduction in proliferation was observed in both cell lines at differing concentrations: 20 microM for MCF-7 and 10 microM for MDA-MB-231 cells. Annexin V staining showed an increase in apoptosis in both cell lines of 31 % in MCF-7 and 12 % in MDA-MB-231 cells compared to their respective controls. In addition, 12 % of the MCF-7 cells were arrested at G0/G1, compared to 62 % of control cells. These results demonstrate that treatment with berberine inhibits growth in both MDA-MB-231 and MCF-7 cells. In addition, they show that this partly occurs through the induction of apoptosis in MDA-MB-231 cells, and through both cell cycle arrest and induction of apoptosis in MCF-7 cells. Thus, berberine may be a novel therapeutic drug for breast cancer.


Molecular Oncology | 2011

NFIB is a potential target for estrogen receptor-negative breast cancers

Hyeong-Gon Moon; Ki-Tae Hwang; Jeong‐Ah Kim; Hee Sung Kim; Min-Joo Lee; Eun-Mi Jung; Eunyoung Ko; Wonshik Han; Dong-Young Noh

The association between nuclear factor I/B (NFIB) gene and triple negative breast cancer has been previously suggested.


Breast Cancer Research | 2011

Transglutaminase 2 facilitates the distant hematogenous metastasis of breast cancer by modulating interleukin-6 in cancer cells

Keunhee Oh; Eunyoung Ko; Hee Sung Kim; Ae Kyung Park; Hyeong-Gon Moon; Dong-Young Noh; Dong-Sup Lee

IntroductionInflammation has been implicated in cancer aggressiveness. As transglutaminase 2 (TG2), which has been associated with inflammatory signaling, has been suggested to play a role in tumor behavior, we propose that TG2 may be an important linker inducing interleukin (IL)-6-mediated cancer-cell aggressiveness, including distant hematogenous metastasis.MethodsTo investigate the role for TG2 and IL-6, TG2-knocked-down and IL-6-knocked-down cancer cells were generated by using shRNA. Human breast cancer cell xenograft model in highly immunocompromised mice and human advanced breast cancer primary tumor tissue microarrays were used in this study.ResultsIL-6 production in human breast cancer cells was dependent on their TG2 expression level. In vitro tumor-sphere formation was dependent on TG2 and downstream IL-6 production from cancer cells. Primary tumor growth in the mammary fat pads and distant hematogenous metastasis into the lung was also dependent on TG2 and downstream IL-6 expression levels. The effect of TG2 expression on human breast cancer distant metastasis was investigated by analyzing a tissue microarray of primary tumors from 412 patients with their clinical data after 7 years. TG2 expression in primary tumor tissue was inversely correlated with recurrence-free survival (P = 0.019) and distant metastasis-free survival (DMFS) (P = 0.006) in patients with advanced breast cancer. Furthermore, by using public datasets that included a total of 684 breast cancer patients, we found that the combined high expression of TG2 and IL-6 was associated with shorter DMFS, compared with the high expression of IL-6 only (P = 0.013).ConclusionsWe provide evidence that TG2 is an important link in IL-6-mediated tumor aggressiveness, and that TG2 could be an important mediator of distant metastasis, both in a xenograft animal model and in patients with advanced breast cancer.


Journal of Korean Medical Science | 2009

Fibrin Glue Reduces the Duration of Lymphatic Drainage after Lumpectomy and Level II or III Axillary Lymph Node Dissection for Breast Cancer: A Prospective Randomized Trial

Eunyoung Ko; Wonshik Han; Jihyoung Cho; Jong Won Lee; So Young Kang; So-Youn Jung; Eun-Kyu Kim; Ki-Tae Hwang; Dong-Young Noh

This randomized prospective study investigated the effect of fibrin glue use on drainage duration and overall drain output after lumpectomy and axillary dissection in breast cancer patients. A total of 100 patients undergoing breast lumpectomy and axillary dissection were randomized to a fibrin glue group (N=50; glue sprayed onto the axillary dissection site) or a control group (N=50). Outcome measures were drainage duration, overall drain output, and incidence of seroma. Overall, the fibrin glue and control groups were similar in terms of drainage duration, overall drain output, and incidence of seroma. However, subgroup analysis showed that fibrin glue use resulted in a shorter drainage duration (3.5 vs. 4.7 days; p=0.0006) and overall drain output (196 vs. 278 mL; p=0.0255) in patients undergoing level II or III axillary dissection. Fibrin glue use reduced drainage duration and overall drain output in breast cancer patients undergoing a lumpectomy and level II or III axillary dissection.


BMC Cancer | 2008

CD24 cross-linking induces apoptosis in, and inhibits migration of, MCF-7 breast cancer cells

Jong Bin Kim; Eunyoung Ko; Wonshik Han; Jeong Eon Lee; Kyung-Min Lee; Incheol Shin; Sangmin Kim; Jong Won Lee; Jihyoung Cho; Ji-Yeon Bae; Hyeon-Gun Jee; Dong-Young Noh

BackgroundThe biological effects of CD24 (FL-80) cross-linking on breast cancer cells have not yet been established. We examined the impact of CD24 cross-linking on human breast cancer cell line MCF-7.MethodsMCF-7 and MDA-MB-231 cells were treated with anti-rabbit polyclonal IgG or anti-human CD24 rabbit polyclonal antibodies to induce cross-linking, and then growth was studied. Changes in cell characteristics such as cell cycle modulation, cell death, survival in three-dimensional cultures, adhesion, and migration ability were assayed after CD24 cross-linking in MCF-7.ResultsExpression of CD24 was analyzed by flow cytometry in MDA-MB-231 and MCF-7 cells where 2% and 66% expression frequencies were observed, respectively. CD24 cross-linking resulted in time-dependent proliferation reduction in MCF-7 cells, but no reduction in MDA-MB-231 cells. MCF-7 cell survival was reduced by 15% in three-dimensional culture after CD24 cross-linking. Increased MCF-7 cell apoptosis was observed after CD24 cross-linking, but no cell cycle arrest was observed in that condition. The migration capacity of MCF-7 cells was diminished by 30% after CD24 cross-linking.ConclusionOur results showed that CD24 cross-linking induced apoptosis and inhibited migration in MCF-7 breast cancer cells. We conclude that CD24 may be considered as a novel therapeutic target for breast cancer.

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Wonshik Han

Seoul National University Hospital

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Dong-Young Noh

Seoul National University

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Eun-Kyu Kim

Seoul National University

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Jihyoung Cho

Seoul National University

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Jong Bin Kim

Seoul National University

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Ki-Tae Hwang

Seoul National University

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Hyeong-Gon Moon

Seoul National University

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D-Y Noh

Seoul National University Hospital

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