使用奈米載體輔助專一性鑑定膀胱腫瘤

Abstract

膀胱癌又可以稱做泌尿上皮癌，經由膀胱鏡的診斷區分成肌肉侵入型的膀胱癌和非肌肉侵入型的膀胱癌這兩種形式。泌尿上皮癌又以形成非肌肉侵入型的膀胱癌為主。經尿道膀胱腫瘤切除術 (Transurethral resection of bladder tumor, TURBT)是治療非肌肉侵入型膀胱癌的第一線方法。而選擇性定位膀胱腫瘤對TURBT尤其重要。藉由伊文思藍 (Evans blue, EB) 的膀胱鏡檢查常用於輔助定位膀胱腫瘤的位置，但它在尿液滴注膀胱的期間會被沖刷脫色。因此，迫切需要開發一種替代的成像策略以幫助外科醫生精確定位腫瘤。本論文研究的目的是設計和開發裝載EB的奈米成像系統，藉由增強泌尿上皮的附著，以改善EB在腫瘤部位的滯留和累積量。我們首先製備具有硫醇基的二氧化矽奈米顆粒，由於硫醇基可與黏蛋白 (mucin) 中的半胱胺酸形成雙硫鍵，進而滯留該奈米顆粒於黏膜之上。本研究中藉由IVIS系統分析硫醇基修飾的二氧化矽奈米顆粒所攜帶之EB(EB@MSN-SH)之螢光強度，將對於被EB@MSN-SHEB染色之腫瘤球體，和灌流至小鼠膀胱且模擬尿液沖刷狀況的模式進行觀察。相對於純EB的染色，EB@MSN-SH所釋放之EB可累積在有膀胱癌的小鼠膀胱中，且經過多次沖刷後仍保有較多的EB殘留。從in vitro和in vivo的實驗證實我們的奈米成像系統用於膀胱腫瘤定位的可行性。本論文研究所研發的奈米成像系統具有很大的潛力，可以幫助外科醫生在進行TURBT時定位膀胱腫瘤的位置。

Bladder cancer so-called urothelial carcinoma (UCC), can be classified into two types via cystoscopy: one is muscle-invasive bladder cancer (MIBC), the other is non-muscle invasive bladder cancer (NMIBC). The primary form of UCC is the NMIBC. The TURBT remains the first-line treatment for NMIBC. The selective localization of bladder tumor is particularly important for TURBT. Evans Blue (EB) mediated white-light cystoscopy detection was frequently used to aid the detection of bladder tumor, but we often found it destained during the bladder instillation. Thus, it is in urgent need to develop an alternative imaging strategy facilitating surgeon to precisely localize the tumor. This study aims to design and develop the nano-image system that cargo EB and also can enhance the urothelial attachment to prolong the retention time and accumulation in the tumor sites. We designed a thiol-functionalized silica-based nanoparticle, exhibiting mucoadhesivity that was attributed to the formation of a disulfide bond between a thiol-functionalized nanoparticle and cysteine-rich subdomains of mucus. In this study, the EB was loaded into the thiol-functionalized nanoparticles, and subsequently used to stain the NBT-II bladder tumor spheroid or instill into the mouse bladder while mimicking urination. IVIS (in vivo image system) was used herein to monitor the EB fluorescence intensity. Compared to the group stained with free EB, the group treated with thiol-functionalized nanoparticle appeared to accumulated more EB in the bladder of tumor-bearing mice, even after five cycles of instillation. In vitro and in vivo studies were carried out to confirm the feasibility of our nano-imaging system for the location of bladder tumor. Our nano-imaging system holds great potential to aid visualization of superficial bladder tumor for surgeon during transurethral resection.