Identifying targets for combination therapy with FOLFIRINOX and investigating cell polarity loss as a potential driver of invasion in basal-like PDAC

摘要 胰腺导管腺癌(PDAC)是一种致命的疾病，其五年生存率令人沮丧。 即使在目前的治疗下，也有9%的人。PDAC有两种分子肿瘤亚型，基底样型PDAC较多 攻击性强，与较短的生存时间有关。最近的临床试验发现，基底样PDAC 患者对包括FOLFIRINOX在内的一线化疗药物无效，因此找到更好的药物至关重要 此子类型的治疗选项。为了研究PDAC亚型，有机化合物被利用，正如他们已经显示的那样 来代表两种分子亚型，与传统的2D细胞系不同。首先，这项研究旨在识别基因 其耗竭通过CRISPR/CAS9功能丧失增加基础样PDAC对FOLFIRINOX的敏感性 筛选395个碱基样标记物基因在碱基样PDAC有机物中。合成杀伤力命中可能是 未来作为药物靶点与FOLFIRINOX联合使用作为更有效的治疗药物的研究 基本型PDAC的策略。为了研究基底样PDAC的生物学，我将研究 用类器官模型研究PDAC亚型中细胞极性的失调。初步数据显示， 基底样PDAC的特征是细胞极性的丧失，而经典的PDAC则维持这种极性。类基座 有机化合物不像经典的有机化合物那样组织形成中空的管腔，而最不同的是 磷酸化的蛋白质和亚型之间的途径涉及细胞黏附和细胞极性。调控失调 细胞极性的改变可能会增加癌细胞的侵袭性，潜在地导致基底样PDAC的不良预后。 使用荧光显微镜，这项研究将确定细胞极性标记的定位是否 与经典的相比，基底样的PDAC以与细胞极性丧失一致的方式改变。它还将 被测试细胞极性基因的遗传耗竭是否导致从经典的向基底型的转变 表型，通过器质管腔的丧失和侵袭性增加来衡量。了解这一方面 亚型生物学可能导致未来的治疗策略，利用细胞极性将基底样PDAC转化为 一种更经典的表型，因为经典的PDAC对当前的治疗更敏感。总体而言，这个项目 将促进我们对PDAC亚型的生物学基础的理解，并朝着 基底样型PDAC的治疗策略。这一项目将得到世界银行 北卡罗来纳大学教堂山分校和药理学系，以及叶仁仁博士和 高拉夫·古普塔。

Abstract Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with a dismal five-year survival rate of 9% even with current treatments. There are two molecular tumor subtypes of PDAC; basal-like PDAC is more aggressive and associated with shorter survival times. Recent clinical trials have found that basal-like PDAC patients fail to respond to first-line chemotherapies including FOLFIRINOX, so it is critical to find better treatment options for this subtype. To study PDAC subtypes, organoids are utilized as they have been shown to represent both molecular subtypes, unlike conventional 2D cell lines. First, this study aims to identify genes whose depletion increases basal-like PDAC sensitivity to FOLFIRINOX using a CRISPR/Cas9 loss-of-function screen targeting 395 basal-like marker genes in basal-like PDAC organoids. The synthetic lethality hits may be studied in the future as drug targets for use in combination with FOLFIRINOX as a more efficacious therapeutic strategy for basal-like PDAC. To study the biology of basal-like PDAC, I will investigate the role of dysregulation of cell polarity in the PDAC subtypes using organoid models. Preliminary data suggest that basal-like PDAC is characterized by a loss of cell polarity while classical PDAC maintains it. Basal-like organoids do not organize to form hollow lumens like classical organoids and the most differentially phosphorylated proteins and pathways between subtypes involve cell adhesion and cell polarity. Dysregulation of cell polarity may increase cancer cell invasion, potentially contributing to poor outcomes in basal-like PDAC. Using fluorescence microscopy, this study will determine whether the localization of cell polarity markers is altered in basal-like PDAC compared to classical in a manner consistent with a loss of cell polarity. It will also be tested whether genetic depletion of cell polarity genes results in a shift from classical to basal-like phenotype, as measured by loss of organoid lumens and increased invasion. Understanding this facet of subtype biology could lead to future therapeutic strategies leveraging cell polarity to convert basal-like PDAC to a more classical phenotype, as classical PDAC is more responsive to current treatments. Overall, this project will advance our understanding of the biology underlying PDAC subtypes and move toward the development of therapeutic strategies for basal-like PDAC. This project will be supported by the extensive resources of the UNC Chapel Hill and the Department of Pharmacology as well as by co-mentorship by Drs. Jen Jen Yeh and Gaorav Gupta.