Spatial Distribution of Endogenous Tissue Protease Activity in Gastric Carcinoma Mapped by MALDI Mass Spectrometry Imaging

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Highlights

• •New MALDI MS imaging sample preparation workflow reveals tissue protease activity.
• •Differential time- and inhibitor concentration-dependence confirm active proteases.
• •Mouse gastric tumor displays high protease activity compared to surrounding tissue.
• •Proteomic data and biochemical protease activity assay support MALDI MSI results.

     

免疫组化与影像学检测对肝癌的诊断价值

目的:通过对比免疫组化标记物与影像学检查诊断肝癌的特异性与敏感性,探讨两种方法在肝癌诊断中的价值以指导临床诊断。方法:对本院收治的180例拟诊肝癌的患者行螺旋CT增强扫描检查,并测定AFP、AFU、SF、CA199等免疫组化标记物,通过手术或经皮穿刺活检对患者确诊后,比较CT检查与、AFP、AFU、SF、CA199四项免疫组化联合检查的特异性与敏感性。结果:特异性比较:AFP、AFU、SF、CA199的特异性显著低于CT增强扫描(P0.05),免疫组化联合检查与CT增强扫描的特异性无显著差异(P0.05);敏感性比较,AFU、SF、CA199、联合检查的敏感性显著低于CT增强扫描(P0.05),AFP的敏感性与CT增强扫描无显著差异(P0.05)。结论:免疫组化的联合检测可以提高肝癌诊断的敏感性与特异性,因此应对拟诊肝癌的患者首先进行免疫组化联合检测,免疫组化异常患者可进行CT增强扫描等影像学检查进一步诊断。     

MALDI Mass Spectrometry Imaging: A Novel Tool for the Identification and Classification of Amyloidosis

Amyloidosis is a group of diseases caused by extracellular accumulation of fibrillar polypeptide aggregates. So far, diagnosis is performed by Congo red staining of tissue sections in combination with polarization microscopy. Subsequent identification of the causative protein by immunohistochemistry harbors some difficulties regarding sensitivity and specificity. Mass spectrometry based approaches have been demonstrated to constitute a reliable method to supplement typing of amyloidosis, but still depend on Congo red staining. In the present study, we used matrix‐assisted laser desorption/ionization mass spectrometry imaging coupled with ion mobility separation (MALDI‐IMS MSI) to investigate amyloid deposits in formalin‐fixed and paraffin‐embedded tissue samples. Utilizing a novel peptide filter method, we found a universal peptide signature for amyloidoses. Furthermore, differences in the peptide composition of ALλ and ATTR amyloid were revealed and used to build a reliable classification model. Integrating the peptide filter in MALDI‐IMS MSI analysis, we developed a bioinformatics workflow facilitating the identification and classification of amyloidosis in a less time and sample‐consuming experimental setup. Our findings demonstrate also the feasibility to investigate the amyloid's protein composition, thus paving the way to establish classification models for the diverse types of amyloidoses and to shed further light on the complex process of amyloidogenesis.     

Proteomic analysis of human papillomavirus‐related oral squamous cell carcinoma: Identification of thioredoxin and epidermal‐fatty acid binding protein as upregulated protein markers in microdissected tumor tissue

Human papillomavirus (HPV) infection has been identified as an etiologic agent for a subset of oral squamous cell carcinoma (OSCC) with increasing incidence. HPV DNA‐positivity may confer better prognosis but the related oncogenic mechanisms are unknown. For the identification of HPV relevant proteins, we analyzed microdissected cells from HPV DNA‐positive (n = 17) and HPV DNA‐negative (n = 7) OSCC tissue samples. We identified 18 proteins from tumor tissues by peptide fingerprint mapping and SELDI MS that were separated using 2‐DE. Among a number of signals that were detected as significantly different in the protein profiling analysis, we identified thioredoxin (TRX) and epidermal‐fatty acid binding protein as upregulated in HPV related tumor tissue. This study, investigating for the first time proteomic changes in microdissected HPV infected tumor tissue, provides an indication on the oncogenic potential of viruses.     

Tumor metastasis in an orthotopic murine model of head and neck cancer: possible role of TGF-beta 1 secreted by the tumor cells

In an orthotopic murine model of head and neck cancer, combined subcutaneous and intratumoral vaccination with recombinant vaccinia virus expressing interleukin-2 (rvv-IL-2) induced significant tumor regression early on therapy. However, its efficacy was restricted by recurrent tumor growth and loco-regional metastases. In this study, we explored the mechanism of tumor metastasis. We compared the levels of expression of a number of molecules involved in tumor metastasis, which included transforming growth factor-beta1 (TGF-beta1), E-cadherin, matrix metalloproteinases (MMPs): MT1-MMP, MMP-2, MMP-9, their tissue inhibitors (TIMPs): TIMP-1/TIMP-2, and pro-angiogenic factors CD31, VEGF-R2, and iNOS between primary and metastatic tumors by real-time RT-PCR and immunohistochemistry. We detected spontaneous lymph node and tongue metastasis. Metastasis was delayed in rvv-IL-2 treated mice. Cultured tumor cells expressed negligible amount of TGF-beta1. Untreated or metastatic tumors, on the other hand, expressed high levels of TGF-beta1 and secreted TGF-beta1 in the sera of tumor-bearing mice. Levels of TGF-beta1 in the sera suddenly jumped at the time when tumor metastasis started. In the metastatic tumors, levels of MT1-MMP, MMP-2, and MMP-9 were significantly elevated (P < 0.001), while levels of TIMP-1/TIMP-2 and E-cadherin were decreased (P < 0.001) compared to control or primary tumors. Levels of CD31, VEGF-R2, and iNOS were also significantly elevated in the metastatic lesions (P < 0.001). The concurrence of high levels of TGF-beta1 in the sera, expression of proteins involved in metastasis and initiation of metastasis suggested possible role of TGF-beta1 in on setting the metastatic cascade in this model.     

Multi-photon Imaging of Tumor Cell Invasion in an Orthotopic Mouse Model of Oral Squamous Cell Carcinoma

Loco-regional invasion of head and neck cancer is linked to metastatic risk and presents a difficult challenge in designing and implementing patient management strategies. Orthotopic mouse models of oral cancer have been developed to facilitate the study of factors that impact invasion and serve as model system for evaluating anti-tumor therapeutics. In these systems, visualization of disseminated tumor cells within oral cavity tissues has typically been conducted by either conventional histology or with in vivo bioluminescent methods. A primary drawback of these techniques is the inherent inability to accurately visualize and quantify early tumor cell invasion arising from the primary site in three dimensions. Here we describe a protocol that combines an established model for squamous cell carcinoma of the tongue (SCOT) with two-photon imaging to allow multi-vectorial visualization of lingual tumor spread. The OSC-19 head and neck tumor cell line was stably engineered to express the F-actin binding peptide LifeAct fused to the mCherry fluorescent protein (LifeAct-mCherry). Fox1^nu/nu mice injected with these cells reliably form tumors that allow the tongue to be visualized by ex-vivo application of two-photon microscopy. This technique allows for the orthotopic visualization of the tumor mass and locally invading cells in excised tongues without disruption of the regional tumor microenvironment. In addition, this system allows for the quantification of tumor cell invasion by calculating distances that invaded cells move from the primary tumor site. Overall this procedure provides an enhanced model system for analyzing factors that contribute to SCOT invasion and therapeutic treatments tailored to prevent local invasion and distant metastatic spread. This method also has the potential to be ultimately combined with other imaging modalities in an in vivo setting.     

MALDI Mass Spectrometry Imaging of Early‐ and Late‐Stage Serous Ovarian Cancer Tissue Reveals Stage‐Specific N‐Glycans

Epithelial ovarian cancer is one of the most fatal gynecological malignancies in adult women. As studies on protein N‐glycosylation have extensively reported aberrant patterns in the ovarian cancer tumor microenvironment, obtaining spatial information will uncover tumor‐specific N‐glycan alterations in ovarian cancer development and progression. matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is employed to investigate N‐glycan distribution on formalin‐fixed paraffin‐embedded ovarian cancer tissue sections from early‐ and late‐stage patients. Tumor‐specific N‐glycans are identified and structurally characterized by porous graphitized carbon‐liquid chromatography‐electrospray ionization‐tandem mass spectrometry (PGC‐LC‐ESI‐MS/MS), and then assigned to high‐resolution images obtained from MALDI‐MSI. Spatial distribution of 14 N‐glycans is obtained by MALDI‐MSI and 42 N‐glycans (including structural and compositional isomers) identified and structurally characterized by LC‐MS. The spatial distribution of oligomannose, complex neutral, bisecting, and sialylated N‐glycan families are localized to the tumor regions of late‐stage ovarian cancer patients relative to early‐stage patients. Potential N‐glycan diagnostic markers that emerge include the oligomannose structure, (Hex)₆ + (Man)₃(GlcNAc)₂, and the complex neutral structure, (Hex)₂ (HexNAc)₂ (Deoxyhexose)₁ + (Man)₃(GlcNAc)₂. The distribution of these markers is evaluated using a tissue microarray of early‐ and late‐stage patients.     

Production of Tissue Microarrays, Immunohistochemistry Staining and Digitalization Within the Human Protein Atlas

The tissue microarray (TMA) technology provides the means for high-throughput analysis of multiple tissues and cells. The technique is used within the Human Protein Atlas project for global analysis of protein expression patterns in normal human tissues, cancer and cell lines. Here we present the assembly of 1 mm cores, retrieved from microscopically selected representative tissues, into a single recipient TMA block. The number and size of cores in a TMA block can be varied from approximately forty 2 mm cores to hundreds of 0.6 mm cores. The advantage of using TMA technology is that large amount of data can rapidly be obtained using a single immunostaining protocol to avoid experimental variability. Importantly, only limited amount of scarce tissue is needed, which allows for the analysis of large patient cohorts ^{1 2}. Approximately 250 consecutive sections (4 μm thick) can be cut from a TMA block and used for immunohistochemical staining to determine specific protein expression patterns for 250 different antibodies. In the Human Protein Atlas project, antibodies are generated towards all human proteins and used to acquire corresponding protein profiles in both normal human tissues from 144 individuals and cancer tissues from 216 different patients, representing the 20 most common forms of human cancer. Immunohistochemically stained TMA sections on glass slides are scanned to create high-resolution images from which pathologists can interpret and annotate the outcome of immunohistochemistry. Images together with corresponding pathology-based annotation data are made publically available for the research community through the Human Protein Atlas portal (www.proteinatlas.org) (Figure 1) ^{3 4}. The Human Protein Atlas provides a map showing the distribution and relative abundance of proteins in the human body. The current version contains over 11 million images with protein expression data for 12.238 unique proteins, corresponding to more than 61% of all proteins encoded by the human genome.     

人胃癌组织及胃正常组织氨基酸差异研究

对 2 2例胃癌组织及其癌边组织、胃正常组织氨基酸进行了测定。发现胃癌组织氨基酸总量低于癌边组织氨基酸总量 ,癌边组织氨基酸总量又低于胃正常组织氨基酸总量。癌中组织与癌边组织相比有 8种氨基酸明显降低 ,P <0 .0 1 ;其中三种为人体必需氨基酸 ,三种为生糖氨基酸。胃癌组织与胃正常组织相比 3种生糖氨基酸明显降低 ,P<0 .0 5。结果表明 :胃癌组织存在明显的氨基酸代谢异常     

乳腺癌免疫组化检测在乳腺癌患者诊治中的意义分析

目的：探讨免疫组化检测在乳腺癌患者诊治中的价值。方法：随机选取2011年1月-2013年1月的68例经过空心穿刺活捡并病理确诊的乳腺癌患者为研究对象,均采用免疫组化检测ER、PR、P53、Bcl-2,全部采用CEF化疗方案治疗3个月后手术治疗,再运用免疫组化SP法检测化疗前后乳腺癌组织中以上指标的阳性表达率情况。结果：ER、PR化疗前后比较无统计学意义（P〉0．05）;而P53、Bcl-2比较有明显的差异性（P〈0．05）;ER、PR的阴性和阳性和疗效情况无明显差异性,而P53、Bcl-2的阴性和阳性表达和化疗的效果有明显的差异性,P〈0．05,具有统计学意义。结论：免疫组化检测中ER、PR对乳腺癌化疗前后无明显差异性,而化疗可通过抑制P53的表达来抑制乳腺癌增值并通过升高Bcl-2表达来调整肿瘤细胞分化。     

Three-dimensional (3D) anatomic location,extension, and timing of severe osteoradionecrosis of the mandible

BackgroundThe purpose of this study was to describe the topography, extension (volume), and timing of severe osteoradionecrosis (ORN) that required mandible resection in patients previously treated for head and neck cancer at a high-volume Veterans Affairs Medical Center.Materials and methodsThe records from a reference hyperbaric oxygen clinic were retrospectively analyzed (n = 50, 2018–2021). Inclusion criteria were: I) severe ORN defined as progressive ORN that required resection; II) pathologic confirmation of ORN; and III) availability of pre-operative CT-imaging. Using a radiotherapy (RT) imaging software, we performed a detailed volumetric (3D) analysis of the bone involvement by ORN. Time intervals from RT to surgery for ORN and from surgery to the last follow-up were calculated.ResultsAll patients that met inclusion criteria (n = 10) were male with significant smoking history (median 47.5 pack-years) and a median age of 57 years old at the time of RT. The primary tumors were: oropharynx (n = 6), oral cavity (n = 3) and nasopharynx (n = 1). The median time from RT to ORN surgery was 8 years. The most common ORN location was the posterior lateral body (molar) and six patients had associated fractures. The mean ORN volume was 3.6 cc (range: 0.6–8.3), corresponding to a mean 6.3% (range: 0.7–14) of the total mandibular volume. After a median follow-up of 13.5 months, no recurrence of ORN occurred. Three patients died of non-cancer and non-ORN-recurrence related causes (1 y OS 77.1%).ConclusionSevere ORN occurred after a median of 8 years from the previous RT and usually affected the posterior lateral body. Surgical resection achieved excellent ORN control.     

Assessing the need for adaptive radiotherapy in head and neck cancer patients using an automatic planning tool

BackgroundUnbiased analysis of the impact of adaptive radiotherapy (ART) is necessary to evaluate dosimetric benefit and optimize clinics’ workflows. The aim of the study was to assess the need for adaptive radiotherapy (ART) in head and neck (H&N) cancer patients using an automatic planning tool in a retrospective planning study.Materials and methodsThirty H&N patients treated with adaptive radiotherapy were analysed. Patients had a CT scan for treatment planning and a verification CT during treatment according to the clinic’s protocol. Considering these images, three plans were retrospectively generated using the iCycle tool to simulate the scenarios with and without adaptation: 1) the optimized plan based on the planning CT; 2) the optimized plan based on the verification CT (ART-plan); 3) the plan obtained by considering treatment plan 1 re-calculated in the verification CT (non-ART plan). The dosimetric endpoints for both target volumes and OAR were compared between scenarios 2 and 3 and the SPIDERplan used to evaluate plan quality.ResultsThe most significant impact of ART was found for the PTVs, which demonstrated decreased D98% in the non-ART plan. A general increase in the dose was observed for the OAR but only the spinal cord showed a statistical significance. The SPIDERplan analysis indicated an overall loss of plan quality in the absence of ART.ConclusionThese results confirm the advantages of ART in H&N patients, especially for the coverage of target volumes. The usage of an automatic planning tool reduces planner-induced bias in the results, guaranteeing that the observed changes derive from the application of ART.     

基于免疫组化和癌症基因组图谱数据分析的脾酪氨酸激酶在宫颈癌中的表达研究

摘要 目的：探讨Syk 在宫颈癌中的表达及其临床意义。方法：应用免疫组化检测Syk在宫颈癌、癌前病变(CIN)和相应的正常宫颈组织中的表达。借助R2生物信息平台挖掘Syk在TCGA数据库305例宫颈鳞癌中的mRNA表达及其与预后的关系。结果：免疫组化结果显示,Syk在宫颈癌巢分化较好的中心区表达较强,在分化较低的癌巢周边区表达较弱。Syk 染色主要定位在宫颈癌和正常宫颈组织的细胞质和细胞膜,正常宫颈组织基底细胞无 Syk 表达,8例CIN组织细胞核中可见Syk表达, 但宫颈癌组织细胞核中未见Syk表达。Syk在宫颈癌、CIN和正常宫颈组织中的阳性率分别是76%、54%、40%,三组间的表达差异具有统计学意义（P=0.001）。Syk 在深度浸润和淋巴结转移中表达较强。数据挖掘结果显示,Syk mRNA在305例不同临床分期的宫颈癌中均表达,Syk mRNA高表达组219例,Syk mRNA低表达组73例,其中13例生存数据缺失,Syk高表达组的患者预后较差。结论：Syk在宫颈癌中的表达提示Syk在宫颈癌中具有致癌蛋白的作用,Syk在某些CIN中的核表达可能与更好的预后相关。     

西北地区汉族人核苷酸剪切修复蛋白的表达与头颈鳞癌发病风险的相关性研究

目的:初步探讨西北地区汉族人核苷酸剪切修复蛋白表达水平与头颈鳞癌发病风险的相关性,从翻译水平为头颈鳞癌提供新的筛检标志物。方法:收集118例头颈鳞癌患者和88例健康对照,均为西北地区汉族人。通过反向蛋白芯片实验检测研究对象外周血淋巴细胞中的5个核心核苷酸剪切修复蛋白的相对表达水平,采用卡方检验分析两组间一般特征的差异,并计算蛋白相对表达水平间的差异,logistic回归计算OR值及95%CI,最后通过绘制接受者操作特性曲线评价模型的诊断价值。结果:病例组XPB (Xeroderma pigmentosum, complementation group B)的表达水平显著低于对照组(P=0.013)。Logistic回归分析结果显示XPB高表达者相比,其低表达者头颈鳞癌患病风险的OR为1.74(95%CI,0.99-3.06)。此外,XPB的蛋白表达水平降低与SCCHN风险增加之间存在剂量反应关系(P_(trend)=0.042)。最后,我们通过接受者操作特性曲线计算曲线下面积,评估XPB表达水平的效应对于头颈鳞癌易感性筛检能力。包含XPB表达水平的效应模型中曲线下面积显著改善(P=0. 048)。结论:在西北地区汉族人中XPB的相对表达水平的降低与头颈鳞癌患病风险的增加相关。XPB表达水平的降低可能在既往吸烟者的头颈鳞癌患病风险中发挥更重要的作用。     

重组人甲状旁腺素（1-34）在大鼠体内的组织分布和排泄

目的：研究重组人甲状旁腺素（1-34）[rhPTH（1—34）]在大鼠体内的组织分布和排泄情况,为进一步的临床实验提供参考。方法：用^125I-同位素示踪法结合TCA酸沉淀法测定各主要器官组织的总放射性浓度和酸沉淀部分放射性浓度,获得rhPTH（1-34）的尿粪排泄和胆汁排泄数据。结果：各主要器官组织的总放射性浓度排序由高到低依次为：尿、肾、膀胱、肠内容物、肌肉、血清、肾上腺、空肠、肝、肺脏、卵巢、肠淋巴结、脾、胸腺、心脏、脂肪、睾丸和脑;大鼠皮下注射。^125I-rhPTH（1-34）后,骨骼组织中放射性分布低于血浆,但消除缓慢,血浆浓度4h较15min降低了78％,而骨骼浓度多数仅降低了50％以下;注射后72h,尿、粪分别排出注入放射性量的73．6％±10．9％和3．2％±1．3％,尿、粪合计排出注入放射性量的76．8％±11,4％;注射后12h,胆汁中累积排出注入放射性的6．64％±1．04％。经分子筛排阻HPLC证实,^125I-rhPTH（1-34）不与大鼠的血浆蛋白发生结合。结论：rhPTH（1-34）在泌尿系统中的分布较高,在脂肪和脑中最低,提示药物不易透过血脑屏障;就全身放射性分布而言,在骨骼中分布较高,提示药物具有一定的靶向性;rhPTH（1-34）主要经尿的形式排泄。     

Mitochondria as a critical target of the chemotheraputic agent cisplatin in head and neck cancer

Cisplatin is among the most important chemotherapeutic agents ever developed. It is a critical component of therapeutic regimens in a broad range of malignancies. However, more than a generation after its clinical introduction, the exact mechanism of cisplatin action on tumor cells is not fully defined. The preponderance of research over the last three decades has focused on cisplatin interactions with nuclear DNA which are felt to lead to apoptotic cell death in sensitive cells. However, recent data have shown that cisplatin may have important direct interactions with mitochondria which can induce apoptosis and may account for a significant portion of the clinical activity associated with this drug. These direct interactions between cisplatin and mitochondria may have critical implications for our understanding of this class of drugs and the development of new therapeutic agents.