摘要:釐清幽門螺旋桿菌相關之胃淋巴癌的真實範疇,是否也包含胃瀰漫大型B 細胞淋巴癌。研究背景:除了低惡性度胃黏膜相關淋巴組織淋巴瘤(以下簡稱MALToma) 和高惡性度胃MALToma 可經由抗生素治療而痊癒,我們的初步臨床實驗亦證實,胃瀰漫大型B 細胞淋巴癌(以下簡稱DLBCL) 仍與幽門螺旋桿菌(以下簡稱HP) 有相關。重要的是,這些患者也可經由HP 根除治療(抗生素治療) 而痊癒。再者,我們初步研究顯示,CagA 蛋白質參與胃淋巴癌致癌機制,並廣泛地表現在HP 相關胃淋巴癌(包括低惡性度胃MALToma,高惡性度胃MALToma,和無MALT 組織成分之胃DLBCL) 的淋巴癌細胞上。CagA 的表現也與HP 相關胃淋巴癌之共同臨床病理特徵有關。研究假說:我們認為HP 相關的胃淋巴癌範疇,遠比我們想像的還廣泛,可能包括無MALT 組織成分之胃DLBCL (單純胃DLBCL)。為了證實這假說,我們將在傳統的胃MALToma中,分析CagA 的表現、表基因體及基因體、腫瘤細胞與腫瘤微環境間傳遞訊息和轉錄圖譜。並藉由這些分子病理表徵,去推斷單純胃DLBCL 是否有部份仍與HP 相關。研究特殊目標:1. 藉由完整分析CagA 蛋白質表現、臨床病理特徵和分子及基因改變現象,來廓劃出與HP 相關之胃淋巴癌的範疇。2. 探索HP 相關胃淋巴癌之腫瘤細胞與腫瘤微環境之相互間,其單純或層級間的傳遞訊息。3. 藉由結合表基因體及基因體,和轉錄圖譜之訊息,幫助我們釐清和廓劃出與HP相關之胃DLBCL 的生物意義。研究對象與方法:1. 藉由完整分析CagA 蛋白質表現、臨床病理特徵和分子及基因改變現象,來廓劃出與HP 相關之胃淋巴癌的範疇首先我們將在一系列低惡性度胃MALToma 中,證實CagA 蛋白質表現與HP依賴性有相關性。當確定CagA 表現為HP 依賴性機轉之重要生物角色,我們將針對胃淋巴癌(MALToma 和DLBCL) 患者(分為CagA 陽性及CagA 陰性兩組)去做一完整性分析並比較這兩組間,其臨床病理特徵、HP 依賴性狀況、HP 相關CpG 島甲基化表型(CIMP)、基因表現、CagA 訊息傳遞路徑(SHP2、ERK、P38和BCL2) 和臨床預後之差別性。2. 探索HP 相關胃淋巴癌之腫瘤細胞與腫瘤微環境之相互間,其單純或層次間的傳遞訊息為了釐清腫瘤微環境在HP 相關胃淋巴癌之淋巴癌致癌機制中所扮演之重要角色,我們將評估HP 相關胃淋巴癌之淋巴癌與腫瘤微小環境的相互關係,並針對腫瘤浸潤T 細胞、Th17 輔助細胞、IL22、CD4+CD25+/Foxp3+(Tregs,T 細胞調節細胞), 活化T 細胞核內因子(簡稱NFAT)、吞噬細胞(CD68、CD169)、樹突狀細胞、生物激素及生物激素接受體和CagA 訊息傳遞去深入研究。我們將使用雷射截取顯微手術方法和逆反性蛋白質微陣方法去分析胃MALToma 和DLBCL (分為CagA 陽性及CagA 陰性兩組) 之配對淋巴癌細胞和基質細胞這兩者間相互傳遞訊息間的層級關係。3. 藉由結合表基因體及基因體,和轉錄圖譜之訊息,幫助我們釐清和廓劃出與HP相關之胃DLBCL 的生物意義為了釐清表基因不正常及表基因所改變之分子表現是否與HP 相關胃DLBCL之致病機制有關,我們將使用DNA 甲基微陣法去定量和分析一整個世代胃DLBCL 患者(分為CagA 陽性及CagA 陰性兩組)之甲基化圖譜。而面對於新診斷胃DLBCL 患者,我們將使用訊息傳遞網路圖譜(結合以免疫表徵為主方式及搭配多樣化特殊磷酸之流式細胞分析儀方法),去深入瞭解胃DLBCL 之淋巴癌細胞間的相關訊息傳遞圖譜。最後,這些表基因表徵將與組織型態表現,基因體表徵,和轉錄表現做一整體性分析,去獲得HP 相關胃淋巴癌之細胞來源和致癌機制的真實線索。預期研究結果:1. 胃淋巴癌細胞中若有CagA 表現,是HP 相關胃淋巴癌的重要生物標記。而且相當大部分胃DLBCL 淋巴癌仍與HP 有相關性,並可藉由HP 根除治療而有效治癒。2. 具有CagA 蛋白質陽性表現之三種不同組織型態的胃淋巴癌(低惡性度MALToma,高惡性度MALToma 和DLBCL) 具有共同臨床病理特徵、生物表現、免疫表現及分子特徵。
Abstract: To clarify whether the full spectrum of H. pylori (HP)-related gastriclymphoma can be extended to diffuse large B-cell lymphoma (DLBCL).Background: In addition to the classical gastric low-grade and high-grademucosa-associated lymphoid tissue lymphoma (MALToma), we have recently providedpreliminary evidence that gastric DLBCL may also be closely related to Helicobaterpylori (HP); and most importantly, they can all possibly be cured by HP eradicationtherapy. Our preliminary data showed that CagA is expressed in a wide spectrum ofHP-related gastric lymphoma and its expression is associated with common specificclinicopathologic features.Hypothesis: HP-related gastric lymphoma may include pure DLBCL (without histologicevidence of MALT). To prove this, we will analyze CagA expression, epigenomic,genomic, cell-microenvironment communication signals, and transcriptional profiling inclassical MALToma, and then extrapolate to pure DLBCL.Specific aims:1. Delineation of the spectrum of HP-related gastric lymphoma throughcomprehensive analyses of the relationship between CagA expression,clinicopathologic features, and molecular/genetic changes.2. Exploration of the nature and hierarchy of communication signals betweenHP-related lymphoma cells and their microenvironments.3. Characterization of the biologic significance of HP-related gastric DLBCL bycombined epigenomic, genomic, and transcriptional profiling.Patients and Methods:1. Delineation of the spectrum of HP-related gastric lymphoma throughcomprehensive analyses of the relationship between CagA expression,clinicopathologic features, and molecular/genetic changes: We will start byconfirming the role of CagA expression in HP-dependence status in a series oflow-grade gastric MALToma. Once the biologic role of CagA expression isconfirmed, we will further carry out a comprehensive approach to compare theclinicopathologic features, HP-dependence status, HP-related CpG islandmethylator phenotype (CIMP), genetic features, CagA-signaling pathway (SHP2,ERK, P38, and BCL2), and clinical outcome between CagA-positive andCagA-negative gastric MALToma and DLBCL.2. Exploration of the nature and hierarchy of communication signals betweenHP-related lymphoma cells and their microenvironments: To clarify the crucialrole of tumor microenvironment in lymphomagenesis of HP-related gastriclymphoma, we will evaluate the interaction between tumor microenvironment andlymphoma cells in a series of HP-related gastric lymphoma—with special attentionof the relationship between tumor-infiltrating T cells, Th17 helper cells, IL-22,CD4+CD25+/Foxp3+(Tregs), nuclear factor of activated T cells (NFAT),macrophage (CD68, CD169), dendritic cells, chemokine/chemokine receptors, andCagA-signaling. We will combine laser capture microdissection and reverse-phaseprotein microarrays to analyze the two patient subgroups of gastric MALToma andDLBCL (CagA-positive versus CagA-negative) with matched lymphoma cells andstroma cells to understand the hierarchy of communication signals.3. Characterization of the biologic significance of HP-related gastric DLBCL bycombined epigenomic, genomic, and transcriptional profiling: To clarify whetherepigenetic abnormalities and epigenetic alterations-related molecular changes cancause lymphomagenesis of HP-related gastric DLBCL, we will use array technologyto quantitatively assess methylation profiles in a cohort of gastric DLBCL patients(CagA-positive group versus CagA-negative group). For newly diagnosed gastricDLBCL patients, we will use the signaling network profiles (by combination of theimmunophentyping-based and multiplexed phospho-specific flow cytometry) tocomprehensively analyze the signaling profiles of lymphoma cells. Finally, theepigenetic patterns will correlate with the histologic characteristics, genetic changes,and transcriptional features (affymetrix microarray), to obtain clues of cellular originand mechanisms associated with HP-related gastric DLBCL.Major anticipated achievements: (1) CagA expression in tumor cells is a hallmark ofHP-related gastric lymphoma, and a substantial portion of gastric DLBCLs are HP-related,and is curable by HP eradication therapy. (2) Three histologic subtypes of CagA-positivegastric lymphoma (low-grade MALToma, high-grade MALToma, and DLBCL) may sharecommon clinicopathologic, biologic, immunologic, and molecular features.