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Kim S, Baek N, Kwon B, Kwon Y, Ro J, Park I, Lee E. New HER2 Assay Using Trastuzumab for the Selection of Trastuzumab Responding Breast Cancer: The Positivity Is Significantly Associated with Pathologic Complete Response after Preoperative Chemotherapy. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-6050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background:The evaluation of HER2 status is required for trastuzumab therapy in breast cancer. Although there are a few methods for an evaluation of HER2 status, theoretically the better method would be to check trastuzumab uptake itself in the tumor after trastuzumab administration. Therefore, we developed a different HER2 test (QHerceptest) using trastuzumab to improve an accuracy in the selection of patient for trastuzumab therapy.Patients and Methods:31 patients with HER2 positive (IHC 3+: 19 and IHC 2+ with FISH positive: 12) early breast cancer who were enrolled in a phase II preoperative paclitaxel, gemcitabin and trastuzumab (PGH) combination chemotherapy trial were evaluated. The pre-chemotherapy tumor specimens were obtained from the breast mass (n=24) or metastatic lymph nodes (n=7). After completing 6 cycles of PGH therapy, all patients underwent breast conserving surgery or mastectomy. We applied trastuzumab and Quantum dot conjugated goat anti-human IgG (QD-IgG, 655nm, Invitrogen) in the process of immunuhistochemistry for HER2 using formalin-fixed paraffin embedded specimen. After antigen retrieval, trastuzuamb was applied followed by QD-IgG. The result of QHerceptest was scored as negative, weak positive, moderate positive, or strong positive, and its relative uptake (RU) were quantified by imaging analysis program (Q-IHC, http://www.bio-miblab.org).Results:The uptake of trastuzumab by QHerceptest was heterogenous, varying between 1.3% to 193.7%. Twenty one of 31 (67.7%) patients achieved pathologic complete response (pCR): 11 of 12 patients (91.7%) with QHerceptest strong positive tumors, 6 of 9 patients (66.7%) with QHerceptest moderate positive tumors, and 4 of 7 patients (57.1%) with QHerceptest weak positive tumors, and none of 3 patients (9.4%) with QHerceptest negative tumors (p=0.0203). Besides, RU was significantly different between non-pCR and pCR groups (43.9±38.3, 80.8±47.1, p=0.0396)Conclusion:We developed a new HER2 assay using trastuzumab and applied to clinical specimen. This assay showed heterogenous trastuzumab uptake in this patient population. Although the data need to be verified by further study, the assay could possibly eliminate patients among HER2 positive breast cancer who will not get benefit by trastuzumab .This study was supported by NCC Grant No 0710292-2 and NCC Grant No 0610240.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6050.
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Jung S, Kim H, Min S, Lee S, Park C, Kwon Y, Kim E, Ko K, Lee K, Park I, Shin K, Lee S, Kim S, Kang H, Ro J. Prognosis of Metaplastic Breast Cancer: Poorer Than the Rest of Triple-Negative Breast Cancer. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-4057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: The biologic behavior of metaplastic breast cancer (MBC) has not been well elucidated due to its rarity and heterogeneity. This study was designed to assess the clinical and tumor characteristics and outcomes of MBC patients as compared with invasive ductal carcinoma (IDC) in general and the triple-negative (TN) subtype.Materials and methods: This study included 35 MBC and 2,839 IDC patients diagnosed at the National Cancer Center, Korea between 2000 and 2008. We, retrospectively, reviewed the clinicopathologic characteristics and clinical outcomes.Results: The mean age was 47.4 years for MBC group and 48.3 years for IDC group. The MBC group presented with larger tumors (≥ T2, 78.8% vs 41.0%; P<0.001), higher histologic grade (grade 3, 92.0% vs 44.6%; P<0.001), fewer ER and PgR positivity (ER+, 14.3% vs 69.0% ; P<0.001 and PgR+, 25.7% vs 66.1%; P<0.001), higher Ki-67 expression (35.5%±26.2% vs 20.6% ±19.8%; P=0.024) and more TN subtypes (48.6% vs 11.9%; P<0.001) than IDC group. Excluding de novo stage IV patients, 14 of 32 (43.7%) MBC patients and 260 of 2782 (9.4%) IDC patents developed disease recurrence with a median follow-up of 36.2 months (range, 4.9-117.8 months). MBC was a poor prognostic factor for disease recurrence in univariate and multivariate analysis (HR 5.19; 95% CI, 2.04-13.18; P=0.001). MBC patients demonstrated aggressive pathologic features and experienced more disease recurrence (HR 4.77; 95% CI, 1.99-11.44; P=0.001) even when compared with 330 patients with TN subtype.Conclusions:Patients with metaplastic breast carcinoma appeared to have inherent aggressive tumor biology with poorer clinical outcomes than those with IDC in general and TN subtype.Partly supported by NCC Grant No 0610240
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4057.
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Park I, Ro J, Lee K, Kim S, Lee Y. Single Nucleotide Polymorphisms of CYP19A1, rs10459592 and rs4775936 Predict Clinical Benefit of Letrozole in Patients with Metastatic Breast Cancer. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-2117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
BackgroundThe CYP19A1 gene encodes the enzyme aromatase, which is involved in the production of estrogen in various tissues. We evaluated the efficacy of an aromatase inhibitor, letrozole in metastatic breast cancer patients according to DNA polymorphisms of the aromatase gene CYP19A1.Patients and methodsPatients (n=113) with hormone receptor positive metastatic breast cancer were treated with letrozole. Monthly GnRH agonist was added in premenopausal patients. DNA was isolated from peripheral blood samples and was genotyped for 50 polymorphisms of CYP19A1 by iPLEX Gold assay based on matrix-associated laser desorptional ionization, time-of-flight mass spectrometry.ResultsAmong 50 examined single nucleotide polymorphisms (SNP), 10 SNPs were revealed as monomorphic for Korean population. After trimming of the data using HWE test, rs10459592 (T/G) and rs4775936 (C/T), which were located in exon I.6 of CYP19A, were significantly associated in an over-dominant model with higher disease control rate (CR+PR+SD≥ 6months) (HR=2.82 [95% CI 1.21-6.59], p=0.0149; HR=2.62 [95% CI 1.12-6.10], p=0.0238, respectively). In linkage disequilibrium analysis, these were strongly linked (D'=1.0, r2=0.936), and subsequent haplotype analysis showed a statistical significance with regard to higher disease control rate (HR=2.61 [95% CI 1.12-6.1], p=0.0238). Median time to progression (TTP) with a median follow-up of 85.7 months (range 9.7-107.4 months) was improved in patients having over-dominant form of rs10459592 without statistical significance (median 7.74 months [95% CI 6.48-9.00] vs. median 12.07 months [95% CI 8.87-15.26], p=0.147). In multivariate analysis, rs10459592 (HR=2.81 [95% CI 1.12-7.06], p=0.027) was an independent factor affecting disease control rate besides age (HR=1.06 [95% CI 1.01-1.12], p=0.019) and HER2 positivity (HR=0.25 [95% CI 1.12-7.06], p=0.027).ConclusionIn patients with hormone responsive metastatic breast cancer treated with aromatase inhibitor, letrozole, the presence of SNPs in the exon I.6 of CYP19A1, rs10459592 and rs4775936 were significantly associated with improved treatment efficacy. Although further study is needed, our data present possible candidate markers for the letrozole treatment in metastatic breast cancer. (NCC grant number 0910320-1)
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2117.
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Keam B, Kim H, Im S, Im S, Han S, Han S, Oh D, Oh D, Kim J, Kim J, Lee S, Lee S, Chie E, Chie E, Han W, Han W, Kim D, Kim D, Cho N, Moon W, Kim T, Kim T, Park I, Noh D, Noh D, Heo D, Heo D, Ha S, Ha S, Bang Y, Bang Y. Single Nucleotide Polymorphism (SNP) in RASSF1 and Clinical Outcomes of Breast Cancer Patients Treated with Neoadjuvant Docetaxel/Doxorubicin Chemotherapy. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-6061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
PurposeThe tumor suppressor gene RASSF1 (Ras association domain family member 1) regulates cell cycle, progression, apoptosis, and microtubule stability, and is inactivated by promoter hypermethylation in breast cancer. We analyzed the SNPs in RASSF1 and their predictive and prognostic value in stage II or III breast cancer patients who received neoadjuvant docetaxel/doxorubicin chemotherapyMethodsA total of 139 stage II or III breast cancer patients who received neoadjuvant docetaxel/doxorubicin chemotherapy were enrolled in this study. The patients received three cycles of neoadjuvant chemotherapy followed by curative surgery, and received additional three cycles of docetaxel/doxorubicin chemotherapy as an adjuvant. Germline DNA from peripheral blood mononuclear cells was extracted. The genotypes were performed using Illumina GoldenGate® Assay. We analyzed 3 SNPs in RASSF1 genes: rs3213621 T>C in 3'UTR, rs2073499 G>A in intron, and rs2073498 C>A in exon 3 Ala133Ser.ResultsThe overall radiologic response rate (RR) for neoadjuvant chemotherapy was 79.8% and 10 patients (7.2%) achieved a pathologic complete remission (pCR). None of the SNPs were correlated with radiologic RR or pCR rate. SNP in intron of RASSF1 (rs2073499) was associated with relapse free survival (RFS). RFS was longer in GA/AA genotype than GG genotype (Hazard ratio [HR]=0.374, p=0.034) After adjusting age and hormone status, prognostic value of RASSF1 SNP remained significant (HR=0.393, p=0.050). Other two SNPs were not significantly associated with RFS.ConclusionsThe GA/AA genotype in SNP of RASSF1 (rs2073499) is associated with significantly longer RFS than the GG genotype. Further research is warranted to identify the biologic characteristics of RASSF1.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6061.
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Malloy DC, Sevigny P, Hadjistavropoulos T, Jeyaraj M, McCarthy EF, Murakami M, Paholpak S, Lee Y, Park I. Perceptions of the effectiveness of ethical guidelines: an international study of physicians. MEDICINE, HEALTH CARE, AND PHILOSOPHY 2009; 12:373-383. [PMID: 19544088 DOI: 10.1007/s11019-009-9212-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Accepted: 06/08/2009] [Indexed: 05/27/2023]
Abstract
The intent of ethics is to establish a set of standards that will provide a framework to modify, regulate, and possibly enhance moral behaviour. Eleven focus groups were conducted with physicians from six culturally distinct countries to explore their perception of formalized, written ethical guidelines (i.e., codes of ethics, credos, value and mission statements) that attempt to direct their ethical practice. Six themes emerged from the data: lack of awareness, no impact, marginal impact, other codes or value statements supersede, personal codes or values dictate, and ethical guidelines are useful. Overall, codes were valued only when they were congruent with existing personal morality. The findings suggest the need to re-evaluate the purpose, content, and delivery of codes for them to improve their function in promoting ethical conduct.
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Yen YF, Kohler SJ, Chen AP, Tropp J, Bok R, Wolber J, Albers MJ, Gram KA, Zierhut ML, Park I, Zhang V, Hu S, Nelson SJ, Vigneron DB, Kurhanewicz J, Dirven HAAM, Hurd RE. Imaging considerations for in vivo 13C metabolic mapping using hyperpolarized 13C-pyruvate. Magn Reson Med 2009; 62:1-10. [PMID: 19319902 PMCID: PMC2782538 DOI: 10.1002/mrm.21987] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2007] [Accepted: 01/11/2009] [Indexed: 12/24/2022]
Abstract
One of the challenges of optimizing signal-to-noise ratio (SNR) and image quality in (13)C metabolic imaging using hyperpolarized (13)C-pyruvate is associated with the different MR signal time-courses for pyruvate and its metabolic products, lactate and alanine. The impact of the acquisition time window, variation of flip angles, and order of phase encoding on SNR and image quality were evaluated in mathematical simulations and rat experiments, based on multishot fast chemical shift imaging (CSI) and three-dimensional echo-planar spectroscopic imaging (3DEPSI) sequences. The image timing was set to coincide with the peak production of lactate. The strategy of combining variable flip angles and centric phase encoding (cPE) improved image quality while retaining good SNR. In addition, two aspects of EPSI sampling strategies were explored: waveform design (flyback vs. symmetric EPSI) and spectral bandwidth (BW = 500 Hz vs. 267 Hz). Both symmetric EPSI and reduced BW trended toward increased SNR. The imaging strategies reported here can serve as guidance to other multishot spectroscopic imaging protocols for (13)C metabolic imaging applications.
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Jeong J, Chae Y, Kim J, Sohn S, Park H, Park J, Yang J, Park I, Lee Y. Association between P53 expression or TP53 codon 72 polymorphism and prognosis in patients with operated invasive breast cancer. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e22175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e22175 Background: The present study analyzed the impact of p53 expression and TP53 codon 72 polymorphism on the prognosis in patients with operated invasive breast cancer. Methods: Two hundred thirty-four patients with ductal breast cancer who underwent surgery with curative intent were enrolled in the present study. The tumor expressions of p53, ER, PR, and HER2 were graded immunohistochemically and TP53 codon 72 polymorphism was determined by a PCR-RFLP assay using genomic DNA extracted from paraffin-embedded tissue. Results: The median age was 49 (range, 24–82) years, and 134 (57.3%) patients were premenopause at the time of diagnosis. Pathologic stages after surgery were as follows: stage I (n=77, 32.9%), stage II (n=110, 47.0%), and stage III (n=47, 20.1%). Tumor overexpression of p53 protein was observed in 59 (25.2%) patients and was associated with an unfavorable relapse-free survival (RFS) in an univariate analysis adjusted to age, stage, and menstrual status. In a multivariate analysis, p53 overexpression was an independent prognostic factor for RFS (HR=2.36; 95% CI=1.09–5.13; p=0.030). However, no associations were observed between the genotype of TP53 codon 72 polymorphism and survival or clinicopathologic characteristics. Conclusions: Overexpression of p53 protein can be considered as a prognostic factor for RFS in the breast cancer patients after surgery. No significant financial relationships to disclose.
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Han J, Lee S, Yun T, Moon Y, Park I, Kim H, Lee J. Randomized phase II study of gefitinib alone or with simvastatin in previously treated advanced non-small cell lung cancer (NSCLC). J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.8057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
8057 Background: Statins reduce not only serum cholesterol levels but also mevalonate synthesis by inhibiting HMG-CoA reductase. Mevalonate is a precursor of several cellular major products including dolichol, geranylpyrophosphate (GPP) and farnesyl-pyrophosphate (FPP). Dolichol has a stimulatory effect on DNA synthesis and is linked to several tumor cell proteins. GPP and FPP cause isoprenylation of Ras and Rho those regulate signal transduction of several membrane receptors crucial for cell proliferation, differentiation, and apoptosis, which result in resistance to gefitinib. Thus depletion of mevalonate metabolites may enhance gefitinib activity in NSCLC. This study compared gefitinib alone with gefitinib plus simvastatin in patients with recurrent NSCLC after at least one chemotherapy. Methods: Between May 2006 and September 2008, 107 patients (51% male, 74% adenocarcinoma, 50% never-smoker, 54% more than two prior regimens) were randomly assigned to gefitinib alone (250 mg/d orally, n=53) or gefitinib plus simvastatin (250mg/d and 40 mg/d orally, respectively, n=54). A cycle was considered as 4 weeks of treatment. Therapy was continued until disease progression or intolerable toxicities. The primary end point was to assess response rate. Secondary end points included time to progression and survival. Median follow-up was 10.1 months. Results: Efficacy was similar for gefitinib and gefitinib plus simvastatin groups. Objective tumor response rates (RR) were 31.5% (95% CI, 19.1 to 43.9) and 32.1% (95% CI, 19.5 to 44.7); median PFS were 1.9 and 2.0 months; and median OS were 9.5 and 12.7 months, respectively. In subgroup analysis, gefitinib plus simvastatin showed a trend for higher RR than gefitinib alone in non-adenocarcinoma group (38.5% vs. 7.7%, p=0.08). Adverse events at both arms were generally mild (grade 1 or 2) and consisted mainly of skin reactions. Conclusions: Gefitinib combined with simvastatin did not improved efficacy compared to gefitinib alone in this unselected patient population, but showed a trend for higher efficacy in non-adenocarcinoma patients. Although it is preliminary, gefitinib combined with simvastatin showed slightly increased OS. Updated survival data will be presented. No significant financial relationships to disclose.
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Yoon S, Yoo C, Park I, Chang H, Kim T, Lee J, Yook J, Oh S, Kim B, Kang Y. Prognostic significance of preoperative serum tumor markers in the patients with curatively resected advanced gastric cancers. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e15515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e15515 Background: We evaluated the prognostic significance of preoperative tumor markers, carcinoembryonic antigen (CEA), carbohydrate antigen 19–9 (CA19–9), and carbohydrate antigen 72–4 (CA72–4), in the patients with curatively resected advanced gastric cancers (AGC). Methods: Preoperative serum tumor markers were available for 667 patients who had been enrolled in a phase III trial of adjuvant chemotherapy (AMC0201). We compared the relapse free survival (RFS) and overall survival (OS) according to patient's pre-treatment clinical characteristics and serum tumor markers by using log rank test and Cox proportional hazard model. Results: Of total 667 patients, 3 year RFS rate and OS rate were 67.4% and 75.0%, respectively. Postoperative pathologic stage was II in 353 (52.9%), IIIA in 202 (30.3%), IIIB in 61 (9.1%), and IV (M0) in 51 (7.6%). CEA, CA19–9, CA72–4 were elevated pre-operatively in 64 of 665 patients (9.6%), 75 of 664 patients (11.3%), and 121 of 639 patients (18.9%), respectively. After the median follow-up of 38.4 months, 209 patients (31.3%) had recurrence, and 164 patients (24.6%) died. In the univariate analysis, location of tumor, type of surgery, Borrmann type, TNM stage, the elevation of CEA and CA72–4 level were significant prognostic factors for RFS and OS. In the multivariate analysis, serum CA72–4 was independent significant prognostic factor for RFS and OS as well as tumor location, Borrmann type, and stage Conclusions: Pre-operative serum CEA and CA72–4 levels were independent prognostic factors as well as clinical characteristics of pathologic stage, tumor location and Borrmann type in patients with curatively resected AGC. No significant financial relationships to disclose.
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Yoo BW, Park JH, Park IH, Lee J, Kim M, Jin JY, Jeon JA, Kim SW, Kim YK. MEMS micromirror characterization in space environments. OPTICS EXPRESS 2009; 17:3370-3380. [PMID: 19259174 DOI: 10.1364/oe.17.003370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This paper describes MEMS micromirror characterization in space environments associated with our space applications in earth observation from the International Space Station and earth's orbit satellite. The performance of the micromirror was tested for shock and vibration, stiction, outgassing from depressurization and heating, and electrostatic charging effects. We demonstrated that there is no degradation of the micromirror performance after the space environment tests. A test bed instrument equipped with the micromirrors was delivered and tested in the ISS. The results demonstrate that the proposed micromirrors are suitable for optical space systems.
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Park I, Yim H, Jang S, Shin D, Lim S, Jeong JI. Deformation of a LCD glass-panel by alignment process in nanoimprint lithography. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:684-687. [PMID: 19441371 DOI: 10.1166/jnn.2009.c003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Deformation of a LCD glass-panel during the alignment is analyzed for a UV-nanoimprint lithography process. In UV-nanoimprint processes for manufacturing LCD panels, a glass-panel should be aligned with respect to the position of fiducial marks on imprint mold and the target glass. The alignment process will place the nano-patterns on the mold into the designated position in the glass-panel. Usually, viscoelastic resin is laminated between the mold and glass-panel. The resin is solidified by ultra-violet light and is designed to be nano-patterns. Thus, shear force would be induced on the panel during alignment process. The shear force can cause deformation of glass-panel, which ultimately causes misalignment of nano-patterns. Thus, deformation analysis for the glass-panel in the alignment process is essential to enhance the accuracy and to reduce alignment cost in nano-imprint. In this work, deformation of the glass panel from the viscous force is calculated by using 'ALGOR' package. The mechanism of misalignment of nano-patterns due to the deformation is analyzed. Finally, the effect of misalignment is discussed, and the experimental results are also presented.
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Kim E, Han W, Park I, Lee J, Ko E, Yu J, Moon H, Noh D. Triple negative phenotype: not affecting survival in young patients with operable breast cancer. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-1083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #1083
Purpose: To investigate the clinicopathological characteristics and outcomes of triple negative breast cancer in young patients.
 Experimental Design: We analyzed 1,498 patients with primary invasive breast cancer who underwent surgery between January 2000 and December 2003. Patients were divided into those < 40 and ≥ 40 years old and into triple negative and non-triple negative groups.
 Results: A total of 326 (21.8%) were aged < 40; relative to patients ≥ 40 years old, the younger group showed larger tumor size, higher lymph node positivity, and elevated Ki-67 index. Recurrence-free survival (RFS; P = 0.0002) and overall survival (OS; P = 0.0483) were significantly lower in the younger group. Three hundred seventy four patients (25.0%) had the triple negative phenotype, and of which 93 (24.9%) were < 40 years old. Univariate survival analysis showed that the triple negative phenotype was not a prognostic factor for either RFS or OS in the younger group. In the older group, however, the triple negative phenotype was a significant prognostic factor for both RFS (P = 0.0103) and OS (P = 0.0081) by univariate analysis, and it remained a significant prognostic factor for OS by multivariate analysis (hazard ratio, 1.9; 95% confidence interval, 1.09-3.44; P = 0.025). When the non-triple negative group was subdivided into luminal and HER2 subtypes, the HER2 subtype showed the worst OS in both age groups (P < 0.001), followed by the triple negative group. However, the difference between the HER2 subtype and the triple negative group was significant only in the younger group (P = 0.0064), but not in the older group (P = 0.1446).
 Conclusions: Triple negative phenotype did not affect survival in patients < 40 years old, because of the markedly poorer survival of non-triple negative tumors of the HER2 subtype in this age group.
Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1083.
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Lim K, Oh D, Chie E, Han W, Im S, Kim T, Park I, Nho D, Ha S, Bang Y. Metaplastic breast carcinoma: clinicopathologic features and prognostic value of triple-negativity. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-1085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #1085
Backgroud Metaplastic breast carcinomas (MBC) are a rare type of breast cancer comprising <1% of all invasive breast cancers and are generally characterized by hormone receptor and human epidermal growth factor receptor 2 (HER2) negativity. There is a paucity of information on prognosis according to hormone receptor and HER2 expression for these rare tumors. The aim of this study was to compare the clinical features and prognosis, between triple negative metaplastic carcinoma (TNMC) and non-triple negative metaplastic carcinoma (NTNMC).
 Material and Methods We retrospectively analyzed MBC patients treated at Seoul National University Hospital between 1996 and 2006. Pathologic, immunohistochemical findings and clinical outcome information were reviewed.
 Results fifty-one patients were identified. The median age at presentation was 45.8 years (range: 27.3-83.8). Median tumor size at diagnosis was 3.0 cm (range: 0.8-12.0). 34 cases (66.7%) were node-negative, 16 (31.4%) node-positive, and 1 (2.0%) were missing. Estrogen receptor (ER)/progesterone receptor (PR) yielded negative results in 49 cases (96.1%) and 48 cases (94.1%), respectively. HER2 overexpression by immunohistochemistry was negative in 41 of 51 (80.4%). At median follow-up of 40.8 months, the 5-year overall survival rate and disease free survival were 73.9% and 64.9%, respectively. Non-triple negativity (p=0.031) correlated significant with overall survival in multivariate analysis.
 Of the 51 patients, 39 (76.5%) were TNMC, and 12 (23.5%) were NTNMC. In TNMC and NTNMC group, median ages were 45.6 and 51.5 years and tumor sizes were 3.0 cm and 3.0 cm, respectively. There were 12 patients (30.8%) in TNMC and 4 patients (33.3%) in NTNMC for lymph node metastasis. Two groups did not differ significantly by age, tumor size, or nodal status. Positive rates for ER, PR and HER2 were 16.7%, 25% and 83.3% in NTNMC. The 3-year overall survival rates in TNMC and NTNMC were 91.4% and 61.9%, respectively (p=0.029). As regards to 3-years disease-free survival, there was no statistically significant difference between TNMC and NTNMC (p=0.694, 75.8% versus 75.0%).
 Discussion MBC mainly has triple negative features. However, in subgroup analysis of MBC, non-triple negative group displayed a poor prognosis compared with triple negative group, which is contrary to the case of invasive ductal carcinoma of breast. Further research exploring mechanism of this result.
Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1085.
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Im S, Lee K, Lee E, Kwon Y, Noh D, Park I, Ahn J, Ahn J, Kim J, Nam B, Ro J. Remarkable complete pathologic response rate after preoperative paclitaxel, gemcitabine, and trastuzumab chemotherapy in HER2 positive stage II/III breast cancer: a phase II multicenter study. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-5105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #5105
Background: Preoperative paclitaxel (P) and gemcitabine (G) combination therapy given on D1/D8 every 3 weeks (wks) for 4 cycles was well tolerated and effective in stage II/III breast cancer (BC) in our previous phase II study, with an 18% pathological complete response (pCR) rate. Adding trastuzumab (H) to the preoperative chemotherapy increases both of the clinical and pathological response rates in HER2 positive BC patients (pts). Thus far, the highest pCR rate reported in the literature was obtained with anthracycline-based regimens in combination with trastuzumab. This study evaluated whether non-anthracycline combination chemotherapy with PGH could improve the pCR rate in HER2 positive BC. Methods: HER2 positive, stage II/III BC pts with cytologically confirmed axillary lymph node (LN), ≥ 18 years of age, with adequate organ function, and good performance status were eligible. No prior therapy was allowed. Pts received H intravenously (iv) at 4 mg/kg on D1 of the first cycle with subsequent weekly doses of 2 mg/kg in combination with P 80 mg/m2 and G 1,200 mg/m2, iv, on D1/D8 every 3 wks for 6 cycles. Within 2 wks postoperatively, patients received H 6 mg/kg every 3 wks for 11 cycles with tamoxifen or an aromatase inhibitor for 5 years if indicated. All pts received postoperative radiation therapy. Initial evaluation included sonogram and MRI of the breast, MUGA scan, or echocardiogram, and PET-CT. Results: All 53 planned pts were enrolled between April 2007 and February 2008. The median age was 43 years (range, 26–61 years), the median primary tumor size by sonogram was 5.3 cm (range, 2.0 to > 12 cm) with 89 % ≥ stage IIIA, 42% T3/T4, and 28% N3. Twenty four tumors (45%) were multiple and 20 tumors (38%) were ER positive. By May 2008, 47 patients completed surgery with a 74% breast conservation rate. Twenty-eight of 47 (60%; 95% CI, 45-72) patients achieved pCR in both the tumor and lymph node, with 68% (32/47; 95% CI, 54-80) pCR in the primary tumor, and 77% (36/47; 95% CI, 63-86) pCR in the axillary LN. Median metastatic focus in 21 positive LNs (n=11 pts) was 1 mm (range, <1–13mm). Grade III/IV adverse events (AE) were neutropenia (53%), febrile neutropenia (4%), and transient elevation of AST/ALT (9%). After 6 cycles of PGH chemotherapy, all patients maintained above normal LVEF. Conclusions: A remarkably high pCR was obtained by non-anthracyline based PGH combination therapy for HER2 positive stage II/III breast cancer. This combination is well tolerated with mild degree of AEs.
 Supported by NCC Grant No 0610240-3. Trastuzumab, paclitaxel, and gemcitabine were supplied by Roche, CJ Cheiljedang CO., and Eli Lilly and CO., respectively.
Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5105.
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Jung S, Han W, Lee J, Yu J, Ko E, Kim E, Moon H, Park I, Hwang K, Oh D, Kim T, Noh D. Ki-67 gives additional prognostic information on St Gallen 2007 and Adjuvant! Online risk categories in early breast cancer. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-1086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #1086
Purpose: We sought to determine the significance of Ki-67, one of the tumor cell proliferation indexes, as a useful prognostic factor in early breast cancer.
 Patients and Methods: 1,080 consecutive patients with stage I or II breast cancer operated between 1998 and 2003 were enrolled. Patients were categorized based on the 2007 St. Gallen consensus and Adjuvant! Online. The expression of Ki-67 in the tumor was assayed using immunohistochemistry (cut-off value: 10%).
 Results: Univariate analysis revealed that tumor size, lymph node involvement, histologic grade, estrogen receptor, progesterone receptor, bcl-2, and Ki-67 (≥10%) were significant for both overall survival (OS) and distant metastasis-free survival (DFS). Of them, lymph node involvement and high Ki-67 expression were identified as independent prognostic factors for OS at multivariate analysis. The survivals of intermediate- and high-risk groups according to 2007 St Gallen consensus were further separated by Ki-67 expression level (5-yr DFS rate=93.3% vs 86.6% for Ki-67<10% and ≥10%, respectively in intermediate-risk group (p=.001); 5-yr DFS rate=83.1% vs 61.5% for Ki-67<10% and ≥10%, respectively in high-risk group (p=.006)). The survivals of low- and high-risk groups according to Adjuvant! Online were further separated by Ki-67 expression level [5-yr DFS rate=97.8% vs 89.5% for Ki-67<10% and ≥10%, respectively in low-risk group (p=.010); 5-yr DFS rate=90.4% vs 82.6% for Ki-67<10% and ≥10% in high-risk group (p=.005)).
 Conclusion: Ki-67 was an independent prognostic factor for DFS and OS in early breast cancer, and could give additional prognostic information on the risk grouping by 2007 St Gallen consensus and Adjuvant! Online.
Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1086.
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Ro J, Park I, Lee K, Kang H, Kim S, Kwon Y, Lee E, Nam B. Comparable efficacies between premenopausal and postmenopausal metastatic breast cancer patients by letrozole with and without goserelin as first line hormone therapy: a phase II parallel group study. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-6134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #6134
Background: The use of goserelin in premenopausal patients(pts) is to produce castrated level of estradiol (E2), and the remaining peripheral E2 production is inhibited by letrozole, which would accomplish comparable clinical outcomes as in postmenopausal metastatic breast cancer (MBC) pts by letrozole alone.
 Methods: Hormone receptor positive pre- and postmenopausal pts with MBC were eligible. Letrozole 2.5 mg once a day was administered with goserelin 3.6 mg every 4 weeks in premenopausal pts and serial serum E2, FSH, LH were measured. Bone mineral density (BMD) and serum bone turnover markers were also checked (n=34).
 Results: Among total 78 pts enrolled, 32 pre- and 38 postmenopausal pts were assessed for efficacy and adverse events (AE). The median age was 42 years (range, 32–52) for pre- and 53 years (range, 33–70) for postmenopausal pts. Baseline characteristics were similar in the two groups, except for significantly longer disease free interval in postmenopausal pts (22.2 months vs. 41.2 months, P=0.01). Clinical benefit (CR+ PR+ SD ≥ 24 weeks) rates (62.5% vs. 68.4%, P=0.62), and objective response (CR + PR) rates (28.1 % vs. 23.7%, P=0.79) were comparable between the two groups. Median TTP was 8.6 months vs. 9.6 months (P=0.61) with a median follow-up of 11.6 months and 14.6 months, respectively. In multivariate analysis, strong ER status was significantly associated with clinical benefit rate (P=0.01), and HER2 positivity (P<0.001) and stage IV presentation (P=0.05) with shorter TTP. In premenopausal pts, the mean E2 level was dropped from 62.3 ± 81.8 pg/mL at baseline to 12.3 ± 2.2 pg/mL at week 2. AEs were mild with significantly more hot flushes in premenopausal pts. In premenopausal pts without bisphosphonate treatment, there was a trend of rising serum levels of osteocalcin (OC) (0% vs. 165%, P=0.065), bone alkaline phosphatase (bALP) (0% vs. 28%, P=0.055), and C-telopeptide (CTx) (0% vs. 108%, P=0.095), as well as a significant reduction in both lumbar spine (P=0.044) and femur (P=0.027) BMD. In contrast, in premenopausal pts with bone metastasis on bisphosphonate, there was no significant change in OC, bALP, CTx, and both BMD. In postmenopausal pts without bisphosphonate treatment, no significant change in OC, bALP, CTx, and femur BMD, while in pts with bone metastasis on bisphosphonate treatment, a significant decrease in OC (0% vs. -22%, P=0.050) and CTx (0% vs. -41%, P=0.020) and increase in both BMD (P=0.044, P=0.038 respectively) were observed.
 Conclusions: Clinical efficacies by letrozole and goserelin therapy in premenopausal MBC pts were comparable to those in postmenopausal pts by letrozole with mild AEs. While a modest increase in both bone formation and resorption especially in premenopausal pts, concurrent bisphosphonate therapy could stabilize bone metabolism in patients even with bone metastasis.
 Supported by NCC Grant No NCS-0610240-3. Letrozole for premenopausal group was supplied by Novartis.
Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6134.
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Park JH, Garipov GK, Jeon JA, Khrenov BA, Kim JE, Kim M, Kim YK, Lee CH, Lee J, Na GW, Nam S, Park IH, Park YS. Obscura telescope with a MEMS micromirror array for space observation of transient luminous phenomena or fast-moving objects. OPTICS EXPRESS 2008; 16:20249-20257. [PMID: 19065163 DOI: 10.1364/oe.16.020249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We introduce a novel telescope consisting of a pinhole-like camera with rotatable MEMS micromirrors substituting for pinholes. The design is ideal for observations of transient luminous phenomena or fast-moving objects, such as upper atmospheric lightning and bright gamma ray bursts. The advantage of the MEMS "obscura telescope" over conventional cameras is that it is capable both of searching for events over a wide field of view, and fast zooming to allow detailed investigation of the structure of events. It is also able to track the triggering object to investigate its space-time development, and to center the interesting portion of the image on the photodetector array. We present the proposed system and the test results for the MEMS obscura telescope which has a field of view of 11.3 degrees, sixteen times zoom-in and tracking within 1 ms.
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Park IH, Ro J, Lee KS, Nam BH, Kwon Y, Shin KH. Trastuzumab treatment beyond brain progression in HER2-positive metastatic breast cancer. Ann Oncol 2008; 20:56-62. [PMID: 18664558 DOI: 10.1093/annonc/mdn539] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Although trastuzumab therapy improves survival in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer, 40% of patients develop brain metastasis (BM) even when extracranial disease is under control. We studied whether trastuzumab therapy beyond or after BM was beneficial to patients with BM. PATIENTS AND METHODS The effect of trastuzumab on survival after BM was analyzed in 78 HER2-positive breast cancer patients. Patients were grouped according to trastuzumab therapy; no treatment and treatment before and after BM were diagnosed. RESULTS Overall survival after the diagnosis of BM as well as time to progression (TTP) of intracranial tumors was prolonged in patients who received trastuzumab after BM was diagnosed. Conversely, BM occurred much later in patients who received trastuzumab before BM. In the multivariate Cox regression model, age at BM <50 years, disease-free interval >or=24 months, TTP of intracranial tumor >or=4.8 months, and trastuzumab treatment after BM were significantly associated with longer survival after the onset of BM. CONCLUSIONS Trastuzumab therapy after the onset of BM in HER2-positive breast cancer patients is associated with a significant survival benefit after BM diagnosis compared with patients who never received or completed trastuzumab before the BM diagnosis.
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Park I, Lee J, Ryu M, Chang H, Kim T, Sym S, Lee S, Jang G, Bae K, Kang Y. Phase I/II and pharmacokinetic study of combination chemotherapy with S-1 and oxaliplatin in patients with previously untreated metastatic or recurrent gastric cancer. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.4557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Rhee J, Oh S, Oh D, Im S, Lee S, Kim D, Heo D, Park I, Bang Y, Kim T. Does triple-negative breast cancer (TNBC) have distinct clinicopathologic characteristics and prognostic significance? J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.21088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
21088 Background: Studies have suggested that TNBC, defined by estrogen receptor-negative, progesterone receptor-negative, and HER2-negative, may represent the subset of breast cancer(BC) with different biologic behavior. Here we investigated the clinicopathologic characteristics of TNBC and its prognostic significance in Korean BC patients. Methods: Patients diagnosed as invasive BC and underwent curative surgery at Seoul National University Hospital between Jan. 2000 and Jun. 2003, were reviewed, retrospectively. We excluded the patients whose immunohistochemistry for hormone receptor nor HER2 status had not been evaluated, and who had been treated with adjuvant trastuzumab or neoadjuvant chemotherapy (CT). Clinicopathologic variables (age, T and N stage, endovascular or lymphatic tumor emboli, nuclear and histologic grade, p53, bcl2, Ki67) and 3 year relapse free survival (3YRFS) rate of TNBC were compared with those of non- TNBC. Results: 1,136 patients were eligible for analysis. The median follow-up was 48.7 months. 341 patients underwent breast conserving surgery followed by adjuvant radiotherapy. 249 patients were TNBC and 62.1% of those were node negative. 86.4% of node negative TNBC, 88.3% of node positive TNBC, 53.9% of node negative non-TNBC, and 90.2% of node positive non-TNBC received adjuvant CT. Compared with non-TNBC, TNBC was correlated with younger age (age<35,14.1% vs. 8.2%, p=0.013), higher nuclear and histologic grade(62.2% vs. 23.6%, p=0.001;60.2% vs. 24.6%, p=0.001, respectively); positive staining for p53 (p=0.001) and higher positivity for Ki67 (p=0.001), suggesting the biologic aggressiveness of TNBC. During the follow-up periods, 17.3% of TNBC were relapsed. In particular, 3YRFS in node negative TNBC and non-TNBC were 86% and 96%, respectively (p<0.001). But, in node positive BC, 3YRFS was not different between TNBC and non-TNBC (80.6% vs. 83%, p=0.99). Conclusions: We confirm that TNBC shows more aggressive clinicopathologic characteristics and in particular, higher relapse in node negative BC. Thus, triple-negativity(TN) may be integrated into risk factor analysis in node negative BC. Final results of more detailed molecular analysis for TNBC would be available in the meeting. No significant financial relationships to disclose.
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Shimato S, Natsume A, Takeuchi H, Wakabayashi T, Fujii M, Ito M, Ito S, Park IH, Bang JH, Kim SU, Yoshida J. Human neural stem cells target and deliver therapeutic gene to experimental leptomeningeal medulloblastoma. Gene Ther 2007; 14:1132-42. [PMID: 17508009 DOI: 10.1038/sj.gt.3302932] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Medulloblastomas are highly malignant neuroectodermal cerebellar tumors of children. One of the reasons for the difficulty for the treatment of medulloblastomas is their inherent tendency to metastasize through the cerebrospinal fluid (CSF) pathway leading to leptomeningeal dissemination. Recently, genetically modified neural stem cells (NSCs) were shown to have the capability of selectively migrating into glioma mass and delivering therapeutic agents with significant therapeutic benefits. In the present study, we applied the NSC strategy to target medulloblastomas, particularly their leptomeningeal dissemination. We used NSCs that were retrovirally transduced with the cytosine deaminase gene (CD-NSCs). In vitro studies demonstrated that CD-NSCs had sufficient migratory activity toward medulloblastoma cells and exerted a remarkable bystander effect on these cells following the application of 5-fluorocytosine (5-FC). It is noteworthy that neutralization of the hepatocyte growth factor blocked their migration In animal studies using our leptomeningeal dissemination model, CD-NSCs implanted directly into CSF space were shown to distribute diffusely within the disseminated tumor cells and could provide remarkable antitumor effect after intraperitoneal administration of 5-FC. Furthermore, CD-NSC treatment followed by 5-FC administration prolonged survival periods significantly in experimental animals. Our data suggest that the CD-NSC strategy can also be applied to target leptomeningeal dissemination of medulloblastomas.
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Song YS, Lee HJ, Park IH, Kim WK, Ku JH, Kim SU. Potential differentiation of human mesenchymal stem cell transplanted in rat corpus cavernosum toward endothelial or smooth muscle cells. Int J Impot Res 2007; 19:378-85. [PMID: 17460699 DOI: 10.1038/sj.ijir.3901539] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
One of the causes of erectile dysfunction (ED) is the damaged penile cavernous smooth muscle cells (SMCs) and sinus endothelial cells (ECs). To investigate the feasibility of applying immortalized human mesenchymal stem cells (MSCs) to penile cavernous ECs or SMCs repair in the treatment of ED, the in vivo potential differentiation of the immortalized human MSCs toward penile cavernous endothelial or smooth muscle was investigated. One clone of immortalized human bone marrow mesenchymal stem cell line B10 cells via retroviral vector encoding v-myc were transplanted into the cavernosum of the Sprague-Dawley rats and harvested 2 weeks later. The expression of CD31, von Willebrand factor (vWF), smooth muscle cell actin (SMA), calponin and desmin was determined immunohistochemically in rat penile cavernosum. Multipotency of B10 to adipogenic, osteogenic or chondrogenic differentiation was found. Expression of EC specific markers (CD31 or vWF protein) and expression of SMC specific markers (calponin, SMA or desmin protein) were demonstrated in grafted B10 cells. When human MSCs were transplanted into the penile cavernosum, they have the potential to differentiate toward ECs or SMCs. Human MSCs may be a good candidate in the treatment of penile cavernosum injury.
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Han J, Lim H, Kim J, Kim M, Lee C, Park I, Cho J. Inductively-coupled control unit for fully implantable middle ear hearing devices. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4704-7. [PMID: 17281291 DOI: 10.1109/iembs.2005.1615521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Recently, fully-implantable middle ear hearing devices (F-IMEHD) to enhance the hearing ability of auditory impaired persons have been developed in several countries. The implantable hearing device requires an external controller and a non-invasive power transmitter for recharging an internal battery of the device. This study shows the implementation of an inductively coupled control unit to be able to recharge the battery and transmit a control signal to the implanted device by designing the structure of coupled antennas and the data protocol using an on-off keying modulation. The implemented control unit has the advantages that it makes the implanted device reduce the power consumption and increase a recharging interval by externally supplying the power of a control signal receiver instead of using an internal battery. Through the experimental results, it has been verified that the implemented control unit has the performance of transmitting power and control signal to a F-IMEHD.
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Lim H, Yoon Y, Lee C, Park I, Song B, Cho J. Implementation of a transcutaneous charger for fully implantable middle ear hearing device. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:6813-6. [PMID: 17281838 DOI: 10.1109/iembs.2005.1616069] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A transcutaneous charger for the fully implantable middle ear hearing device (F-IMEHD), which can monitor the charging level of battery, has been designed and implemented. In order to recharge the battery of F-IMEHD, the electromagnetic coupling between primary coil at outer body and secondary coil at inner body has been used. Considering the implant condition of the F-IMEHD, the primary coil and the secondary coil have been designed. Using the resonance of LC tank circuit at each coil, transmission efficiency was increased. Since the primary and the secondary coil are magnetically coupled, the current variation of the primary coil is related with the impedance of internal resonant circuit. Using the principle mentioned above, the implanted module could transmit outward the information about charging state of battery or coupling between two coils by the changing internal impedance. As in the demonstrated results of experiment, the implemented charger has supplied the sufficient operating voltage for the implanted battery within about 10 mm distance. And also, it has been confirmed that the implanted module can transmit information outward by control of internal impedance.
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Chai S, Herath TC, Park I, Rao HR. Repeated Use of E-Gov Web Sites. INTERNATIONAL JOURNAL OF ELECTRONIC GOVERNMENT RESEARCH 2006. [DOI: 10.4018/jegr.2006070101] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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