유방암에서 17번 염색체 동원체 복제수 증가의 임상병리학적 의의

학위논문(박사)--서울대학교 대학원 :의과대학 의학과,2019. 8. 최기영.서론: 유방암에서 HER2제자리부합법 검사 과정 중 17번 염색체 동원체 부위를 대상으로 한 chromosome enumeration probe (CEP)증가가 때때로 관찰된다. 이와 같은 현상은 17번 염색체 동원체 주변 부위의 국소적 복제수 증가 혹은 증폭에 기인한 것으로 알려져 있다. 염색체 불안정성은 악성 고형성 종양에서 비정상 세포 분열로 인한 염색체 전체 혹은 일부의 손실 또는 증가를 초래하는 결함으로 정의된다. 이러한 유사한 두가지 유전자 이상은 유방암에서 예후 및 치료 반응과 관련이 있다고 알려져 있다. 이번 연구의 목적은 CEP17 복제수 증가의 임상병리학적 의의를 확인하는데 있다. 방법: 분당서울대학교병원에서 2004년부터 2011년까지 HER2 유전자의 형광제자리부합법 결과가 존재하는 945례의 침윤성 유방암을 이용하여 CEP17 복제수 증가의 임상병리학적 소견 및 예후와의 연관성을 분석하였다. CEP17복제수 증가와 염색체 불안정성과의 관계를 확인하기 위하여 다른 463례의 유방암을 이용하여 CEP1, CEP8, CEP11 및 CEP16의 형광제자리부합법 검사를 실시하여 염색체 불안정성의 정도를 측정하였다. 도출된 유방암 염색체 불안정성의 결과와 임상병리학적 소견 및 예후와의 관련성을 분석하였다. 마지막으로 71례의 침윤성 유방암을 이용하여 차세대염기서열분석법을 적용하여 염색체 불안정성 점수를 도출하고 CEP17복제수 증가와의 관련성을 분석하였다. 결과: 945례의 침윤성 유방암 중 185건에서 (19.7%) CEP17 복제수 증가가 (CEP17 ≥3.0) 확인되었다. 전체 유방암 집단 및 HER2 양성 그룹에서 CEP17 복제수 증가는 환자의 예후와 관련이 없었으나 HER2 음성 그룹에서 독립적인 나쁜 예후 인자로 밝혀졌다. 추가적인 분석에서 HER2 음성 및 호르몬 수용체 양성 그룹에서 CEP17 복제수 증가는 높은 병기, 나쁜 조직학적 등급, 림프관 침윤, P53 과발현 및 높은 Ki-67 지수 등의 조직학적 변인과 상관성이 있었고 독립적인 나쁜 예후 인자로 나타났다. 463례의 두번째 유방암 코호트를 이용한 염색체 불안정성 측정에서 높은 염색체 불안정성이 나쁜 예후와 관련된 임상병리학적 인자와 상관성을 보였다. HER2 양성, 높은 Ki-67 지수 및 CEP17 복제수 증가가 염색체 불안정성의 독립적인 예측 인자로 확인되었다. 전체 유방암 그룹, HER2 양성 그룹과 호르몬을 발현하는HER2 음성 그룹에서 높은 염색체 불안정성은 나쁜 예후와 관련성이 있었다. 반면에 염색체 불안정성과 anthracycline 및 taxane제제의 화학요법에 대한 반응과의 관련성은 관찰되지 않았다. CEP17 복제수 증가는 높은 염색체 불안정성을 보이는 그룹에서 통계적으로 유의미하게 자주 관찰되었다. 71례의 유방암을 이용하여 차세대염기서열분석법을 통해 각각의 유방암의 염색체 불안정성 지수를 도출하였고 염색체 불안정성 지수와CEP17 복제수 평균값 사이에 선형 비례 관계를 확인하였다. 결론: 호르몬 수용체를 발현하는 HER2 음성 유방암 그룹에서 CEP17 복제수 증가는 독립적인 예후 인자임을 확인할 수 있었다. 높은 염색체 불안정성은 유방암에서 독립적인 예후 인자임을 확인하였다. 유방암에서 CEP17 복제수 증가는 유방암의 염색체 불안정성에 대한 유용한 예측 인자임을 확인할 수 있었다. 이러한 결과를 통해 HER2 제자리부합법 검사 결과에 HER2뿐 아니라 CEP17 복제수에 대한 평가도 포함될 필요가 있다고 생각된다.Background: Increased copy number of chromosome enumeration probe (CEP) targeting centromere 17 is frequently encountered during HER2 in situ hybridization (ISH) in breast cancer. It is caused by amplification or gain in copy number of the pericentromeric region of chromosome 17. Chromosomal instability (CIN) is defined as a defect that frequently results in the loss or gain of a whole or part of a chromosome during cell division in malignant solid tumors. These similar genetic abnormalities have been reported to be associated with prognosis and treatment response in breast cancer. The aim of this study was to clarify the clinicopathologic implication of CEP17 copy number gain in breast cancer Methods: We analyzed 945 cases of invasive breast cancers whose HER2 fluorescence ISH reports were available from 2004 to 2011 at a single institution and evaluated the association of CEP17 copy number gain with clinicopathologic features of tumors and patient survival. To identify the correlation between CEP17 copy number gain and CIN, CIN status was determined by summing copy number gains of four CEPs (CEP1, CEP8, CEP11 and CEP16) on fluorescence in situ hybridization (FISH) using another 463 cases of breast cancer, and was correlated with clinicopathologic features and survival of the patients. In addition, CIN scores using next generation sequencing were calculated to validate the correlation between CEP17 copy number and CIN in 71 cases of breast cancer. Results: We detected 186 (19.7%) cases of CEP17 copy number gain (CEP17 ≥3.0) among 945 invasive breast cancers. In survival analysis, CEP17 copy number gain was not associated with disease-free survival of the patients in the whole group. Nonetheless, it was found to be an independent adverse prognostic factor in HER2-negative group, but not in HER2-positive group. In further subgroup analyses, CEP17 copy number gain was revealed as an independent poor prognostic factor in HER2-negative and hormone receptor-positive breast cancers, and it was associated with aggressive histologic variables including high T stage, high histologic grade, lymphovascular invasion, P53 overexpression, and high Ki-67 proliferative index. High CIN was associated with adverse clinicopatholgic parameters of breast cancer. Among them, positive HER2 status, high Ki-67 index and CEP17 copy number gain were found as independent predictors for high CIN. High CIN was associated with poor clinical outcome of the patients in whole group and in luminal/HER2-negative and HER2-positive subtypes as well. However, no predictive value of high CIN was found in response to anthracycline or anthracycline & taxane-based chemotherapy. CEP17 copy number was significantly higher in the high-CIN-score group than in the low-CIN-score group. A positive linear correlation between the mean CEP17 copy number and the CIN score, calculated by NGS, was found. Conclusion: We found that elevated CEP17 count can serve as a prognostic marker in luminal/HER2-negative subtype of invasive breast cancer. High CIN was proved as a poor prognostic factor in breast cancer. CEP17 copy number was confirmed as a useful predictor for CIN in breast cancer, suggesting that CEP17 status need to be evaluated carefully and should be included in HER2 ISH report.CONTENTS Abstract 1 Contents 4 List of tables 5 List of figures 7 List of abbreviations 9 Introduction 10 Materials and Methods 13 Results 27 Discussion 60 Conclusion 69 Appendix 70 References 71 Abstract in Korean 78Docto

CYP2C19 Polymorphisms and Smoking Status Affects Responsiveness to the Platelet P2Y12 Receptor Antagonist Clopidogrel

Background: The “comparison of triflusal and clopidogrel effects in secondary prevention of stroke based on cytochrome P450 2C19 (CYP2C19) genotyping (MAESTRO)” study was a prospective, multicenter, randomized, open-label, and blind genotype trial. We performed a subgroup analysis of the MAESTRO study to explore the relationship between VerifyNow P2Y12 assay with regard to CYP2C19 polymorphisms and smoking status in patients with non-cardiogenic ischemic stroke who underwent clopidogrel treatment. Methods: For the study, patients treated with clopidogrel and who underwent VerifyNow P2Y12 assay was selected from the MAESTRO study. Results: Of the 393 patients in 18 hospitals, 256 (65%) patients in 12 hospitals were entered for this subgroup analysis. P2Y12 reaction unit (PRU) was significantly lower and percent inhibition (% INH) was higher in the current smoking group than in the nonsmoking group (p<0.001). The same results were also observed in the good genotype group when compared with the poor genotype group (p<0.001). Among the groups, significant lower PRU and higher % INH was demonstrated in current smoking with good genotype group. However, there was no difference in PRU and % INH between current smoking with poor genotype group and nonsmoking with good genotype group, suggesting that clopidogrel activity was concurrently related to CYP2C19 polymorphisms and smoking status. Conclusions: Regarding secondary stroke prevention, patients who were current smokers and had a poor genotype for clopidogrel metabolism may benefit from clopidogrel treatment similar to that in patients who were nonsmokers and had a good genotype.ope

Prevalence of Unruptured Intracranial Aneurysms: A Single Center Experience Using 3T Brain MR Angiography

Purpose: The purpose of this study was to evaluate the prevalence and risk factors of unruptured intracranial aneurysms (UIAs), which can help establish guidelines of treatment for asymptomatic Korean adults using 3T magnetic resonance angiography (MRA). Materials and methods: Our Institutional Review Board approved this retrospective study, and informed consent was waived. All patients consisted of healthy individuals who underwent brain MRA using 3T magnetic resonance imaging between January 2011 and December 2012 as part of a routine health examination. Patient data and follow-up results were obtained from medical records. Results: A total of 2,118 individuals (mean age=53.9±9.6 years, male:female=1,188:930) who had undergone brain MRA were enrolled in the study. UIAs were found in 80 patients with 105 UIAs (3.77%). Female predominance (55% in UIA vs. 43.47% in non-UIA, P=0.0416) and hypertension were more common in the UIA group (43.75% vs. 28.8%, P=0.004, respectively). The mean size of the aneurysms was 3.10±1.62 mm, and they were all saccular in shape and asymptomatic. The UIAs were most common in the internal carotid artery (59.1%), internal carotid-posterior communicating artery (15.2%), middle cerebral artery (9.5%), anterior communicating artery (8.6%), anterior cerebral artery (4.8%), and vertebral artery (2.9%). Twenty-eight of 80 patients (35%) had multiple aneurysms. The incidence of UIAs increased significantly with age (P=0.014). Conclusion: In single center experience, we demonstrated the characteristics and prevalence of UIAs in asymptomatic adults, which may help establish guidelines or therapeutic standards for UIAs.ope

Comparison of Clopidogrel and Ticlopidine/Ginkgo Biloba in Patients With Clopidogrel Resistance and Carotid Stenting

Background and Purpose: Patients undergoing carotid artery stenting (CAS) who show low responsiveness to clopidogrel may have a higher risk of peri-procedural embolic events. This study aimed to compare the effectiveness and safety of clopidogrel and ticlopidine plus Ginkgo biloba in clopidogrel-resistant patients undergoing CAS. Methods: In this multi-center, randomized, controlled trial, we used platelet reactivity test to select patients undergoing CAS who showed clopidogrel resistance, and compared treatments using clopidogrel and ticlopidine plus ginkgo. The primary outcome was the incidence of new ischemic lesion in the ipsilateral hemisphere of CAS. Detection of microembolic signal on transcranial Doppler was the secondary outcome. The clinical outcomes were also monitored. Results: This trial was discontinued after 42 patients were randomized after preplanned interim sample size re-estimation indicated an impractical sample size. The primary endpoint occurred in 12/22 patients (54.5%) in the clopidogrel group and 13/20 patients (65.0%) in the ticlopidine-ginkgo group (P = 0.610). No significant differences in the presence of microembolic signal (15.0 vs. 11.8%, P = 0.580), clinical outcomes (ischemic stroke or transient ischemic attack, 0.0 vs. 5.5%; acute myocardial infarction 0.0 vs. 0.0%; all-cause death, 4.5 vs. 0.0%), or incidence of adverse events were found in the two groups. In terms of resistance to clopidogrel, treatment with ticlopidine-ginkgo significantly increased the P2Y12 Reaction Units (difference, 0.0 [-0.3-3.0] vs. 21.0 [6.0-35.0], P < 0.001). Conclusions: In patients who showed clopidogrel resistance, ticlopidine-ginkgo treatment was safe and increased P2Y12 Reaction Units; however, compared to clopidogrel, it failed to improve surrogate and clinical endpoints in patients undergoing CAS. This multimodal biomarker-based clinical trial is feasible in neurointerventional research. Clinical Trial Registration: http://www.clinicaltrials.gov. Unique identifier: NCT02133989.ope

A Case of Postpartum Cerebral Angiopathy

Postpartum cerebral angiopathy is a benign, reversible clinicoradiologic syndrome. The clinical significance of this syndrome is the difficulty in differentiating it from other severe disorders such as subarachnoid hemorrhage and cere-bral vasculitis. A 25-year-old woman who developed a severe headache, transient total blindness ,and generalized tonic clonic seizures 14 days postpartum was admitted to our hospital. A MRI of the brain revealed a bilateral anterior cere-bral artery (ACA) infarction. A cerebral angiography showed the narrowing of the M1 and M2 segments of the left middle cerebral artery (MCA), the right MCA M1 segment, and the A1 and proximal A2 segments of the right ACA. Also, it showed the narrowing of the proximal basilar artery portion from which the anterior inferior cerebellar artey arose, P1, P2, and P3 segments of the left posterior cerebral artery (PCA), and the right PCA P1 segment. With the treatment of nimodipine, the abnormalities on these studies were markedly improved two weeks later.ope

Distal hyperintense vessels on FLAIR: an MRI marker for collateral circulation in acute stroke?

BACKGROUND: Hyperintense vessels (HV) on fluid-attenuated inversion recovery imaging are frequently observed in acute ischemic stroke patients. However, the exact mechanism and clinical implications of this sign have not yet been clearly defined. The features of HV and its relevance to other imaging factors are presented here. METHODS: Prominence and location of HV were documented in 52 consecutive patients with middle cerebral artery (MCA) territory infarction, before treatment with IV recombinant tissue plasminogen activator. Pretreatment ischemic lesion volume, perfusion lesion volume, and vessel occlusion were determined in addition to recanalization status and ischemic lesion volume on follow-up imaging. NIH Stroke Scale (NIHSS) was used as a measure of clinical severity. RESULTS: HV distal to arterial occlusion was observed in 73% of patients; more frequent in proximal than distal MCA occlusion patients. Among the 38 patients with proximal MCA occlusion, initial perfusion lesion volume was comparable among patients with different grade distal HV. However, patients with more prominent distal HV had smaller initial, 24-hour, and subacute ischemic lesion volumes and lower initial NIHSS scores. CONCLUSIONS: The presence of distal hyperintense vessels before thrombolytic treatment is associated with large diffusion-perfusion mismatch and smaller subacute ischemic lesion volumes in patients with proximal middle cerebral artery occlusion. DWI = diffusion-weighted imaging; FLAIR = fluid-attenuated inversion recovery; GRE = gradient recalled echo; HV = hyperintense vessels; MCA = middle cerebral artery; MRA = magnetic resonance angiography; MTT = mean transit time; NIHSS = NIH Stroke Scale; PWI = perfusion-weighted imaging; rt-PA = recombinant tissue plasminogen activator; TE = echo time; TI = inversion time; TIMI = thrombolysis in myocardial infarction; TR = repetition time.ope

Hashimoto Encephalopathy Mimicking Acute Ischemic Stroke: Perfusion-Weighted Magnetic Resonance Imaging

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Traumatic Meningeal Enhancement on Post-Fluid Attenuated Inversion Recovery after Minor Head Trauma

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Blood-brain barrier disruption in humans is independently associated with increased matrix metalloproteinase-9

BACKGROUND AND PURPOSE: Matrix metalloproteinases (MMP) may play a role in blood-brain barrier (BBB) disruption after ischemic stroke. We hypothesized that plasma concentrations of MMP-9 are associated with a marker of BBB disruption in patients evaluated for acute stroke. METHODS: Patients underwent MRI on presentation and approximately 24 hours later. The MRI marker, termed hyperintense acute reperfusion injury marker (HARM), is gadolinium enhancement of cerebrospinal fluid on fluid-attenuated inversion recovery MRI. Plasma MMP-9 and tissue inhibitor of matrix metalloproteinase-1 were measured by enzyme-linked immunosorbent assay. Logistic regression models tested for predictors of HARM on 24-hour follow-up scans separately for MMP-9 and the ratio of MMP-9 to TIMP-1. RESULTS: For the 41 patients enrolled, diagnoses were: acute ischemic cerebrovascular syndrome, 33 (80.6%); intracerebral hemorrhage, 6 (14.6%); stroke mimic, 1 (2.4%); and no stroke, 1 (2.4%). HARM was present in 17 (41.5%) patients. In model 1, HARM was associated with baseline plasma MMP-9 concentration (odds ratio [OR], 1.01; 95% confidence interval [CI], 1.001-1.019; P=0.033). In model 2, HARM was associated with the ratio of MMP-9 to tissue inhibitor of matrix metalloproteinase-1 (OR, 4.94; 95% CI, 1.27-19.14; P=0.021). CONCLUSIONS: Baseline MMP-9 was a significant predictor of HARM at 24-hour follow-up, supporting the hypothesis that MMP-9 is associated with BBB disruption. If the association between MMP-9 and BBB disruption is confirmed in future studies, HARM may be a useful imaging marker to evaluate MMP-9 inhibition in ischemic stroke and other populations with BBB disruption.ope

Pharmacogenetics in Cerebrovascular Antithrombotic Therapy

Pharmacogenetics is an emerging field to find out genetic variations that explains different individual responses to given drug. Pharmacogenetics may be the basis of tailored medicine because it can help to predict drug resistance, side effect and dose adjustment. This review discusses current role of pharmacogenetics in antithrombotic treatment in cerebrovascular disease, especially focused on vitamin K antagonist and clopidogrelope