Aptamer mediated targeting of Fanconi Anemia oral cancer initiating cells

摘要： 我们试图使用一种新的细胞内化SELEX(系统进化的配体通过 指数富集法)分离硫代适配子偶联脂质体纳米粒(TA-NP) 将其siRNA内化并送入口腔鳞状细胞肿瘤起始细胞胞浆中 细胞癌，最大限度地减少偏离目标的传递。小干扰RNA在体内的传递和释放 内体到胞浆仍然是翻译抗癌siRNA药物的两大障碍 去诊所。口腔鳞状细胞癌俗称口腔癌(OC)是最常见的 头颈部常见的恶性肿瘤，对全球公共卫生的影响很大。范可尼贫血 (FA)是一种易患OC的遗传性癌症综合征。有证据表明，TIC是 野战癌变、抗拒治疗和疾病复发的关键驱动因素。一种治疗工具 选择性地靶向TIC并向TIC运送抗癌药物为OC提供了巨大的希望 治疗。我们的数据和已发表的研究表明：(1)TIC的FA-OC含量比 散发性OC；(2)Chk1和CD147促进TIC存活和化疗耐药及其机制 卵巢癌中过度表达与预后不良有关。这项建议的主要目标是使用FA- 以OC-TIC为靶细胞，制备TA-NP，用于胞浆递送siRNA。我们 假设分离的TA-NP将促进将siRNA靶向递送到OC-TIC 细胞质，并使OC-TIC中的CD-147/Chk1沉默，扰乱它们的生态位并呈现它们 化疗敏感且易被吉西他滨化疗消除。 目的：(1)阐明RNAi介导的CD147/Chk1沉默在FA-OC-TIC中的作用； (2A)：选择针对FA-OC细胞的TIC组分的TA-Liposomal NP(TA-NP)列表， 在避免肝细胞摄取的同时，使用基于正负细胞摄取的 SELEX；(2B)：确定选定的TA-NP的靶向性和治疗性 在体外和小鼠OC异种移植中的疗效。我们将在FA-OC细胞中分离ALDH+TIC 并检测siRNA介导的CD147和Chk1沉默的效果。(2)我们将使用 一种结合正反选择鉴定OC-TIC特异性的改良共轭SELEX 内化TA-NP。(3)我们将验证TIC靶向性和沉默效果。 分离的TA-NP-sRNA在体外和小鼠原位FA-OC异种移植中。RNAi介导的 抑制CD147和Chk1在OC-TIC中的表达将有助于深入了解它们在OC-TIC中的潜在作用 OC-TIC的肿瘤增殖和耐药特性。拟议的TA-NP将具有 靶向治疗和显像剂体内给药的重要临床潜力 OC-TIC。

Abstract: We seek to use a novel cell-internalization SELEX (Systemic Evolution of Ligands by Exponential enrichment) to isolate thioaptamer-conjugated liposomal nanoparticles (TA-NP) that internalize and deliver its siRNA into the cytosol of tumor initiating cells (TIC) of oral squamous cell carcinoma, minimizing off-target delivery. In vivo delivery and release of siRNA from the endosomes to cytosol remain the two biggest obstacles for translating anticancer siRNA drugs to the clinic. Oral squamous cell carcinoma commonly known as oral cancer (OC) is the most common malignancy of head and neck with high global public health impact. Fanconi anemia (FA) is a hereditary cancer syndrome that predisposes one to OC. Evidence points to TIC as the key driver of field cancerization, resistance to therapy and disease relapse. A therapeutic vehicle that selectively targets and delivers anticancer drugs to TIC offers great promise for OC treatment. Our data and published studies show: (1).TIC is more enriched in FA-OC than sporadic OC; (2) Chk1 and CD147 promote TIC survival and chemoresistance and its overexpression contribute to poor prognosis in OC. The main goal of this proposal is to use FA- OC-TIC as target cells to develop TA- NP for the cytosolic delivery of siRNA. We hypothesize that isolated TA-NP will facilitate targeted delivery of siRNA to OC-TIC cytosol, and silence CD-147/Chk1 in OC-TIC's, disrupting their niche and rendering them chemosensitive and susceptible to elimination by chemotherapy with gemcitabine. Aims:(1): Elucidate the effect of RNAi mediated silencing of CD147/Chk1 in FA-OC-TIC; (2A): Select a list of TA-Liposomal NP (TA-NP) specific for TIC fraction of FA-OC cells, while avoiding hepatocyte uptake, using a positive and negative cell-uptake based SELEX; (2B): Determine the selected TA-NP's targeting specificity and therapeutic efficacy in in vitro and in murine OC xenografts. We will isolate ALDH+ TIC in FA-OC cell lines and examine the effects of siRNA-mediated silencing of CD147 and Chk1. (2) We will use a modified conjugate SELEX with positive and negative selections to identify OC-TIC-specific internalizing TA-NP. (3) We will validate TIC-targeting specificity and silencing efficacy of isolated TA-NP-sRNA in vitro and in murine orthotopic FA-OC xenografts. RNAi mediated inhibition of CD147 and Chk1 in OC-TIC will yield valuable insight into their potential role in the tumor propagating and chemoresistant properties of OC-TIC. The proposed TA-NP will have important clinical potentials for in vivo delivery of therapeutic and imaging agents targeting the OC-TIC.