Tumor suppressive and oncogenic properties of TGF-beta signaling in intrahepatic cholangiocarcinoma: role of Smad3 phosphorylation and long noncoding RNAs

肝内胆管细胞癌(ICC)是一种预后差、发病率上升、治疗机会有限的侵袭性肝癌。迫切需要新的治疗方案来提高患者的存活率。靶向肿瘤微环境(或间质)已被提出为一种新兴的癌症治疗方法。这在ICC中是一个特别有希望的策略，对ICC来说，密集的间质是一个突出的特征。细胞因子在肿瘤细胞与间质的相互作用中起着至关重要的作用。靶向这些介质是阻碍肿瘤发展进程的一种有前景的策略。转化生长因子-β(TGFβ)在肿瘤发病机制中起着关键作用，我们最近发现TGFβ在间质中的表达是预测ICC患者预后不良的一个指标。然而，TGFbeta的作用是复杂的，因为它同时表现出肿瘤抑制和致癌特性，取决于肿瘤的分期。为了提供靶向治疗的理论基础，我们的合作TGFbeta-ICC项目旨在确定在ICC细胞中塑造TGFbeta反应的上下文决定因素。根据我们实验室和其他实验室的初步数据，我们假设C末端和/或连接点的差异Smad3磷酸化(pSmad3C/L)和长的非编码RNA(LncRNA)驱动ICC中TGFbeta的肿瘤抑制和致癌特性。因此，我们将探讨i)不同的Smad3磷酸化和ii)TGFβ调控的lncRNA在ICC中的作用和功能后果。这两个合作伙伴将建立临床上注释良好的ICC集合，并通过免疫染色(IHC，IF)在形态上和通过基因表达谱在分子水平上进行表征。来自患者的ICC组织和ICC细胞系将被用来描述Smad磷酸化及其在ICC发育中的调控。我们将通过功能获得和丧失实验、功能测试和基因组分析来阐明pSmad3C/L信号和与转化生长因子-β相关的lncRNA的作用，包括本课题组最近发现的一种由转化生长因子-β诱导的lncRNA-T-linc1。这些发现的临床相关性将通过使用临床上注释良好的ICC肿瘤的基因表达谱的综合基因组学来检验。我们期待我们的TGFbeta-ICC项目将在基础和翻译层面上为ICC领域带来新的曙光。在基础科学方面，我们希望更好地了解在ICC及其环境中塑造TGFbeta信号后果的上下文决定因素。在翻译层面上，该项目将通过识别从干扰TGFbeta信号中受益的患者，为分层医学提供理论基础。

Intrahepatic cholangiocarcinoma (ICC) is an aggressive liver cancer with poor prognosis, rising incidence and limited therapeutic opportunities. New therapy regimens are urgently required to improve patient survival. Targeting the tumor microenvironment (or stroma) has been proposed as an emerging approach to tackle cancer. This is a particularly promising strategy in ICC, for which the presence of a dense stroma is a prominent feature. Cytokines play a crucial role in the interaction between tumor cells and stroma. Targeting these mediators is a promising strategy to impede the course of tumor development. Transforming growth factor-beta (TGFbeta) plays a key role in cancer pathogenesis and we showed recently that the expression of TGFbeta in the stroma is a predictor of poor prognosis in patients with ICC. However, the action of TGFbeta is complex given that it exhibits both tumor suppressive and oncogenic properties, depending on tumor stage. In order to provide a rationale for targeted therapies, our collaborative TGFbeta-ICC project aims at identifying the contextual determinants that shape the TGFbeta response in ICC cells. Based on preliminary data from our labs and others, we hypothesize that differential Smad3 phosphorylation at C-terminal and/or linker sites (pSmad3C/L) and long non-coding RNA (lncRNA) drive tumor suppressive vs oncogenic properties of TGFbeta in ICC. Accordingly, we will explore the role and the functional consequences of i) differential Smad3 phosphorylation and ii) TGFbeta regulated lncRNA in ICC. Collections of clinically well-annotated ICC will be established by the two partners and characterized morphologically by immunostainings (IHC, IF) and at a molecular level by gene expression profiling. ICC tissue from patients and ICC cell lines will be used to delineate Smad phosphorylation and its regulation in ICC development. Gain and loss of function experiments, functional tests and genomic analysis will be performed to elucidate the role of pSmad3C/L signaling and lncRNA associated with TGF-beta, including T-LINC1, a lncRNA induced by TGF-beta recently identified by our group. Clinical relevance of the findings will be tested by integrative genomics using the gene expression profiles of clinically well-annotated ICC tumors. We expect our TGFbeta-ICC project to shed new light on the field of ICC, both at the basic and translational level. In terms of basic science, we expect a better knowledge of the contextual determinants that shape the consequences of TGFbeta signals in ICC and its environment. At a translational level, the project will provide a rationale for stratified medicine by identifying patients that benefit from interference with TGFbeta signaling.