Lysine-specific histone demethylase 1 (LSD1): A potential molecular target for tumor therapy

Lysine-specific demethylase 1 (LSD1), the first identified histone demethylase, was belonged to the superfamily of the flavin adenine dinucleotide (FAD)-dependent amine oxidases. LSD1 specifically demethylates mono- or dimethylated dimethylated histone H3 lysine4 (H3K4) and H3 lysine 9 (H3K9) via a redox process. Recently evidences showed that LSD1 played an important role in a broad spectrum of biological processes, including cell proliferation, adipogenesis, spermatogenesis, chromosome segregation and embryonic development. Furthermore, LSD1 also could promote progress of tumor by inhibiting the tumor suppressor activity of p53. To date, as a potential drug for discovering anti-tumor drugs, the medical significance of LSD1 inhibitors have been greatly appreciated. Here, we reviewed the remarkable progress being made in understanding of LSD1, mainly on its structure, basic function and medical application in tumor therapy.     

The expression pattern of MUC1 (EMA) is related to tumour characteristics and clinical outcome of invasive ductal breast carcinoma

AIMS: To clarify MUC1 patterns in invasive ductal breast carcinoma and to relate them to clinicopathological parameters, coexpression of other biological markers and prognosis. METHODS AND RESULTS: Samples from 243 consecutive patients with primary ductal carcinoma were incorporated into tissue microarrays (TMAs). Slides were stained for MUC1, oestrogen receptor (ER), progesterone receptor (PR), Her2/neu, p53 and cyclin D1. Apical membrane MUC1 expression was associated with smaller tumours (P = 0.001), lower tumour grades (P < 0.001), PR positivity (P = 0.003) and increased overall survival (OS; P = 0.030). Diffuse cytoplasmic MUC1 expression was associated with cyclin D1 positivity (P = 0.009) and increased relapse-free survival (RFS; P = 0.034). Negativity for MUC1 was associated with ER negativity (P = 0.004), PR negativity (P = 0.001) and cyclin D1 negativity (P = 0.009). In stepwise multivariate analysis MUC1 negativity was an independent predictor of both RFS [hazard ratio (HR) 3.5, 95% confidence interval (CI) 1.5, 8.5; P = 0.005] and OS (HR 14.7, 95% CI 4.9, 44.1; P < 0.001). CONCLUSIONS: The expression pattern of MUC1 in invasive ductal breast carcinoma is related to tumour characteristics and clinical outcome. In addition, negative MUC1 expression is an independent risk factor for poor RFS and OS, besides 'classical' prognostic indicators.     

A comparison of the patterns of laminin expression in fibroadenoma, fibrocystic diseases, pre-invasive and invasive ductal breast carcinoma

The basement membrane (BM), of which laminin is a major glycoprotein component, is an important barrier to tumour cells which must be breeched before metastatic spread can occur. We have compared the pattern of laminin expression in a range of benign and malignant breast lesions to better understand the process of tumour progression. A total of 162 cases of breast samples, comprising 18 fibroadenomas, 22 cases of fibrocystic disease, 96 cases of invasive ductal carcinoma and 26 carcinomas with intraductal components, were evaluated for laminin expression by a standard immunoperoxidase method on formalin-fixed, paraffin-embedded histological sections, using a commercial antibody against human laminin. The pattern of laminin expression was charted as follows: Type I, > 70% of BM complete/continuous; Type II, > 70% of BM moderately disrupted; Type III, > 70% of BM completely disrupted. The Type I pattern was observed in all cases of fibroadenoma and fibrocystic diseases, and in 77% of intraductal carcinoma components. Various patterns of BM disruption were observed in invasive ductal carcinoma. Severity of BM disruption correlated with histological grade of the carcinomas (P < 0.001). Small-sized tumours, those without lymphatic invasion and lymph node-negative tumours showed more complete patterns of laminin expression. The current study suggests that tumour cells with high histological grade possess an enhanced capacity to disrupt the basement membrane, an important step in the metastatic process. The detection of BM disruption by immunohistochemical staining for laminin is technically easy and may be usefully applied for the differentiation of in situ and microinvasive carcinoma.     

Prognostic relevance of tumour cell‐associated uPAR expression in invasive ductal breast carcinoma

Kotzsch M, Bernt K, Friedrich K, Luther E, Albrecht S, Gatzweiler A, Magdolen V, Baretton G, Zietz C & Luther T
(2010) Histopathology 57 , 461–471
Prognostic relevance of tumour cell‐associated uPAR expression in invasive ductal breast carcinoma Aims: The urokinase‐type plasminogen activator receptor (uPAR) is a key molecule for pericellular proteolysis in tumour cell invasion and metastasis. The aim was to evaluate the prognostic impact of uPAR in invasive breast cancer dependent on which cell types within the tumour express uPAR. Methods and results: uPAR expression was analysed by immunohistochemistry in 270 tumour tissue specimens of invasive ductal breast carcinomas using tissue microarrays. For evaluation of uPAR immunoexpression we used the epitope‐mapped, uPAR domain II‐specific monoclonal antibody IID7. High uPAR score values in both tumour cells (uPAR‐Tc) and stromal cells were significantly related to high tumour grade (G3), and inversely correlated with oestrogen receptor status. On multivariate analysis, high uPAR‐Tc values contributed independent prognostic information for disease‐free survival (hazard ratio 1.93, P = 0.007) when adjusted for prognostically relevant clinicopathological parameters, whereas uPAR expression in stromal cells was not related to prognosis. In addition, elevated uPAR‐Tc values were found to be prognostic indicators in clinically relevant subgroups of patients with invasive breast cancer. Conclusions: In invasive breast cancer uPAR expression in invasive carcinoma cells, but not in stromal cells, has a significant impact on patients’ prognosis, and contributes to a more aggressive tumour phenotype.     

Mechanisms of progression of ductal carcinoma in situ of the breast to invasive cancer. A hypothesis

Ductal carcinoma in situ (DCIS), a known precursor lesion of invasive cancer of the female breast, is surrounded by a thick basement membrane and a layer of myoepithelial cells. For DCIS to become invasive, both these barriers must be breached by cancer cells. It has been repeatedly suggested that proteolytic enzymes are somehow involved in this process but a direct proof of this event has never been provided. It is our hypothesis that invasion of the DCIS by capillary vessels derived from the periductal necklace of vessels is the most likely mechanism of breaching the basement membrane, providing an escape hatch for cancer cells. This hypothesis was initially tested on ten randomly selected cases of DCIS, with or without invasion. Capillary vessels were visualized by staining histologic sections with an antibody to CD 34 and, in three cases, by combined stain for CD 34 and collagen IV. In five of the 10 cases of DCIS, the presence of discrete capillary vessels invading DCIS could be documented. In two of these five cases, the vessels subdivided the cancerous ducts into territories of unequal sizes. Vascular invasion of DCIS is a plausible mechanism of breaching the basement membrane in DCIS as a prelude to invasion. This hypothesis must be further tested on a much larger number of cases. The hypothesis, if confirmed, may suggest that invasive cancer derived from DCIS may be prevented by antiangiogenic therapy.     

Matrix metalloproteinase-2 (MMP-2) and MMP-9 expression in invasive ductal carcinoma of the breast

Matrix metalloproteinase-2 (MMP-2) and MMP-9 are gelatinases that play a role in the invasion and metastasis of cancer through the destruction of the basal membrane and extracellular matrix. In this study, we investigated the immunohistochemical expression of MMP-2 and MMP-9 and the correlation between the expression levels and prognostic clinicopathological parameters in 140 patients with invasive ductal carcinoma (IDC). The staining scores for MMP-9 were negative in 21 cases (15%), mild in 27 cases (19%), and strong in 92 cases (66%). MMP-9 expression was increased in high-grade (p=0.001), triple-negative (ER, PR, HER2 negative) (p=0.006), and ER-negative tumors (p=0.004) and tumors with distant metastases (p=0.028). MMP-9 expression was increased in cases with HER2 over-expression/amplification, but no statistically significant difference was found (p=0.215). No correlation was found between lymph node metastasis or tumor size and MMP-9 expression (p=0.492 and p=0.448, respectively). The staining scores for MMP-2 in 140 cases were negative in 10 cases (7%), mild in 25 cases (18%), and strong in 105 cases (75%). MMP-2 expression was increased in ER-negative and high-grade tumors in the lymph node-negative group (p=0.025 and 0.026, respectively). High MMP-9 expression was associated with a shorter disease-free survival and overall survival times (p=0.042 and p=0.046, respectively). In conclusion, increased MMP-9 expression is related to poor prognostic clinicopathological factors in IDC, and hence, it can be utilized as a supplementary prognostic marker. The role of MMP-2 expression in the prognosis of IDC is rather limited.     

Differential copy number aberrations in novel candidate genes associated with progression from in situ to invasive ductal carcinoma of the breast

Only a minority of intraductal carcinomas of the breast give rise to stromally invasive disease. We microdissected 206 paraffin blocks representing 116 different cases of low‐grade ductal carcinoma in situ (DCIS). Fifty‐five were pure DCIS (PD) cases without progression to invasive carcinoma. Sixty‐one cases had a small invasive component. DNA was extracted from microdissected sections and hybridized to high‐density bacterial artificial chromosome arrays. Array comparative genomic hybridization analysis of 118 hybridized DNA samples yielded data on 69 samples that were suitable for further statistical analysis. This cohort included 20 pure DCIS cases, 25 mixed DCIS (MD), and 24 mixed invasive carcinoma samples. PD cases had a higher frequency of DNA copy number changes than MD cases, and the latter had similar DNA profiles compared to paired invasive carcinomas. Copy number changes on 13 chromosomal arms occurred at different rates in PD versus MD lesions. Eight of 19 candidate genes residing at those loci were confirmed to have differential copy number changes by quantitative PCR. NCOR2/SMRT and NR4A1 (both on 12q), DYNLRB2 (16q), CELSR1, UPK3A, and ST13 (all on 22q) were more frequently amplified in PD. Moreover, NCOR2, NR4A1, and DYNLRB2 showed more frequent copy number losses in MD. GRAP2 (22q) was more often amplified in MD, whereas TAF1C (16q) was more commonly deleted in PD. A multigene model comprising these candidate genes discriminated between PD and MD lesions with high accuracy. These findings suggest that the propensity to invade the stroma may be encoded in the genome of intraductal carcinomas. © 2012 Wiley Periodicals, Inc.     

上皮钙依赖粘附素相关分子在乳腺浸润性小叶癌和导管癌中的表达及意义

目的 探讨上皮钙依赖粘附素相关分子α-、β-、γ-catenin在乳腺浸润性小叶癌（ILC）和浸润性导管癌（IDC）中的表达及其意义。方法 采用免疫组织化学LSAB法检测了19例ILC和32例IDC组织中α-、β-、γ-catenin的表达,并根据阳性癌细胞占肿瘤细胞的比例进行半定量化分析和统计学x^2检验。结果 α-、β-、γ-catenin在19例ILC中表达缺失和明显减少的分别为15例（78.9%),10例（52.6%)和16例（84.2%),而在32例IDC癌组织中的表达缺失和明显减少为24例（75.0%),14例（43.8%)和26例(81.3%)例。另外,这3种蛋白在浸润性癌组织中表达强度弱于原位癌灶的表达强度。α-catenin和β-catenin在乳腺浸润性癌中的表达具有明显的正相关性,未发现α-、β-、γ-catenin在乳腺浸润性癌中的表达与有无伴有淋巴结转移病例之间的关系有统计学意义。结论 α-、β-、γ-catenin在乳腺ILC和IDC中表达均为明显缺失和减少,说明这些粘附分子在乳腺浸润性癌发生中确实丧失了其正常的细胞粘附功能。     

乳腺浸润性导管癌微卫星不稳定性

目的 探讨乳腺浸润性导管癌的微卫星不稳定(MSI)性及其与临床病理资料的关系。方法 选取10个微卫星位点，从石蜡包埋的存档标本中选取34例肿瘤组织和其对应的自身正常对照组织，提取DNA后用PCR扩增，6％聚丙稀酰胺凝胶电泳，银染显色后进行微卫星不稳定性分析。用免疫组化S-P法观察p53、c-erbB-2、PR、ER在乳腺癌中表达情况。结果 在34例乳腺浸润性导管癌中有9例(26．47％)至少1个位点出现MSI。MSI和病人年龄、肿瘤大小、病理分级、淋巴结转移、p53、c-erbB-2之间没有明显的相关性。但ER和PR阴性的病例出现MSI的比例远远高于ER和PR阳性病例。结论在乳腺癌的发生、发展过程中出现MSI,并可能和ER、PR的表达降低有关。     

The expression pattern of MUC1 (EMA) is related to tumour characteristics and clinical outcome in 'pure' ductal carcinoma in situ of the breast

AIMS: To classify MUC1 according to five predefined expression patterns in ductal carcinoma in situ (DCIS) and related clinicopathological parameters, coexpression of other biological markers and prognosis. METHODS AND RESULTS: With a manual tissue arrayer, 92% (n = 80) of the 87 DCIS samples were successfully targeted. Immunohistochemistry was carried out for MUC1, oestrogen receptor (ER), progesterone receptor (PR), Her2/Neu, p53 and cyclin D1. Entire membrane expression was related to Her2/neu negativity (P =0.042). Apical membrane expression was associated with low grade (P = 0.027), Her2/neu negativity (P = 0.014) and PR positivity (P = 0.005). Focal cytoplasmic expression was related to high grade (P = 0.006). Diffuse cytoplasmic expression was associated with high grade (P = 0.004), large tumour size (P = 0.046), Her2/neu positivity (P =0.042) and cyclin D1 positivity (P = 0.002). On the basis of these analyses the four patterns were reclassified as membranous or cytoplasmic expression. On multivariate analysis, cytoplasmic MUC1 expression (hazard ratio 8.5, 95% confidence interval 1.0, 73.0; P = 0.04) was the only independent predictor of local recurrence. CONCLUSIONS: Four patterns of MUC1 expression are recognized in DCIS that suggest a relationship to functional differentiation and can be simplified into two types that are clinically relevant and could therefore be helpful in the distinction between different subgroups of DCIS.     

CD24 expression in ductal carcinoma in situ and invasive ductal carcinoma of breast: an immunohistochemistry-based pilot study

CD24 is a small, heavily glycosylated cell surface protein, that is expressed in a large variety of solid tumors. It is considered to play an important role in tumor progression and metastasis. We aimed to evaluate CD24 expression in invasive ductal carcinomas (IDCa), ductal carcinoma in situ (DCIS) and non-tumorous breast tissues, and to investigate the relationship between histopathological parameters, estrogen and progesterone receptors, and c-erbB2 expressions. The study included 34 IDCa, 25 DCIS, and 13 non-tumorous breast tissues. All cases were reevaluated histopathologically, and immunohistochemistry was performed with monoclonal CD24 antibody. The results clearly demonstrated that CD24 expression, including membranous and cytoplasmic staining, was significantly higher in DCIS and IDCa than in the non-tumorous breast (p=0.001, p=0.000, and p=0.035, p=0.000, respectively). Cytoplasmic staining was detected predominantly in neoplastic tissues and was significantly increased in high grade DCIS (p=0.013). In invasive carcinomas, although the level of membranous staining was significantly positively correlated with tumor grade (p=0.040), there was no such an association with the cytoplasmic level. However, it showed a trend towards pT (p=0.089). In conclusion, our results suggest that higher CD24 expression may be associated with malignant transformation and progression in breast cancer biology. Furthermore, higher membranous expression and, in particular, cytoplasmic staining seem to predict malignant transformation, and different patterns of CD24 expression may be associated with different pathological features in breast tumors.     

Analysis of HLA-G gene polymorphism and protein expression in invasive breast ductal carcinoma

The human leukocyte antigen G (HLA-G) is a non-classical HLA class I molecule predominantly expressed in trophoblastic placental cells to protect the fetus during pregnancy. However, evidence has shown that this molecule may be implicated in the immune escape mechanism of tumor cells. Thus, the aim of this study was to evaluate the frequency of 14-bp insertion/deletion HLA-G polymorphism, as well as the expression of this molecule in patients with invasive breast ductal carcinoma (IDC). A significant association between the expression of HLA-G and the presence of metastasis in lymph nodes (p = 0.01) was observed and the expression of HLA-G was significantly higher in patients with shorter survival time (p = 0.03). The analysis suggests that the polymorphism observed in patients with IDC may be inducing a higher expression of the HLA-G molecule, which may possibly contribute to shorter survival time and a worse clinical prognosis for such patients.     

Lysyl oxidase gene expression in the stromal reaction to in situ and invasive ductal breast carcinoma.

Lysyl oxidase is involved in the main pathway of collagen and elastin cross-linking: it has a role in the maturation of fibrillar matrix proteins in fibrosing processes and dictates their stability against metalloproteases. The stromal reaction patterns in ductal breast carcinoma are known to be morphologically varied. This has raised the hypothesis that there might be a differential expression of the lysyl oxidase gene as a function of stromal reaction pattern. The present study investigates this potential correlation and the role of matrix protein cross-linking in stromal differentiation. Lysyl oxidase was detected by immunohistochemistry and lysyl oxidase gene expression by in situ hybridization. Maximal expression was observed in myofibroblasts and myoepithelial cells around in situ tumors and in the reactive fibrosis facing the invasion front of infiltrating tumors. The lysyl oxidase substrates were observed in parallel, resulting in the stabilization of a scar-like peritumor barrier. In contrast, a lack of lysyl oxidase was associated with the loose or scirrhous stroma accompanying invading tumors; here, in situ hybridization revealed type I collagen synthesis, resulting in the deposition of non-cross-linked matrix proteins susceptible to degradation. The early development of a cross-linked matrix around ductal breast carcinoma suggests a possible bost defense mechanism, whereas the synchronous or late stromal reaction lacking lysyl oxidase favors tumor dispersion.     

Immunohistochemical expression of E‐cadherin in sclerosing adenosis,ductal carcinoma in situ and invasive ductal carcinoma of the breast

E‐cadherin (EC) is an important glycoprotein cell‐adhesion molecule that appears to play a significant role in the progression of breast lesions. The objective of this study was to evaluate EC expression in sclerosing adenosis, ductal carcinoma in situ and invasive ductal carcinoma. Samples of breast lesions from 44 women were used in this study, comprising cases of sclerosing adenosis (n = 11), ductal carcinoma in situ (DCIS) (n = 10) and invasive ductal carcinoma (n = 23). Immunohistochemical evaluation of EC expression was assessed semiquantitatively and considered negative (<10% of cells with stained cytoplasmic membranes), positive+ (10–50% of cells stained) or positive++ (> 50% of cells stained). Fisher's exact test was used to compare the distribution of staining intensity in the lesions (P< 0.05). There was a progressive loss of EC expression from benign to malignant lesions. This difference was statistically significant when sclerosing adenosis was compared with DCIS (P < 0.0002), when sclerosing adenosis was compared with invasive ductal carcinoma (P < 0.008) and when DCIS was compared with invasive ductal carcinoma (P < 0.007). The present findings point to a significant association between reduced EC expression and the progression and aggressivity of breast lesions. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.     

ALDH1A1在乳腺浸润性导管癌中的表达及临床意义

目的探讨ALDH1A1在乳腺浸润性导管癌中的表达及临床意义。方法收集2004年至2008年在中国医科大学附属第一医院乳腺外科病房行根治性手术的158例有完整随访资料的乳腺浸润性导管癌组织石蜡标本,采用免疫组化SP法检测ALDH1A1蛋白在乳腺癌组织中的表达,分析其与临床病理因素及预后的关系。结果 ALDH1A1主要表达于细胞浆。乳腺癌浸润性导管癌组织中ALDH1A1表达阳性率为56.3%。乳腺癌浸润性导管癌组织中ALDH1A1的表达与年龄、绝经状态、肿瘤大小、临床分期、临床分级无关(P0.05),而与淋巴结转移相关(P=0.009)。ALDH1A1阳性表达患者无病生存时间(DFS)和总生存时间(OS)均短于ALDH1A1阳性表达患者,差异具有有统计学意义(P=0.022和P=0.011)。Cox比例风险回归分析显示ALDH1A1是影响乳腺浸润性导管癌患者预后的危险因素(P=0.025和P=0.014),但不是独立危险因素(P=0.892和P=0.489)。结论 ALDH1A1蛋白在乳腺浸润性导管癌的发生、发展中起一定作用,与淋巴结转移密切相关,可能是影响乳腺浸润性导管癌预后的重要指标。     

乳腺浸润性导管癌HER2免疫组化检测结果判定的重复性研究

目的 探讨病理医师对乳腺浸润性导管癌HER2免疫组化(immunohistochemistry,IHC)检测结果判定的重复性及其影响因素,寻求提高判读重复性和准确性的措施.方法 参照<乳腺癌HER2检测指南>,2位乳腺专科病理医师共同读片选取56例浸润性导管癌的HER2 IHC切片作为研究对象.4位非专科病理医师独立盲法完成对该组病例IHC切片的前后两轮结果判定.对第一轮4位观察者间的判读重复性和观察者自身的判读重复性进行Kappa分析.同时将2位专科医师共同确定的判读结果作为HER2判读参考分级,4位非专科医师第一轮的判读结果分别与之进行配对Kappa分析.结果 观察者间的判读重复性为中等(K=0.593 9),重复性最高的级别是HER2为0(K=0.811 4),最低的是HER2为2 (K=0.473 6).判读级别简化为阳性和阴性后,观察者间的重复性明显提高(K=0.723 0).4位观察者自身的判读重复性极好(Kw=0.821 9～0.916 5),判读的准确性则与经验有关.结论 采用标准化的检测手段、深入学习和实践现有的判读标准以及联合判读等措施应有助于提高HER2 IHC判读的重复性和准确性.