文献：Albumin conjugation promotes arsenic trioxide transport through alkaline phosphatase-associated transcytosis in MUC4 wildtype pancreatic cancer cells

文献链接：https://www.sciencedirect.com/science/article/abs/pii/S0141813023056556

作者：Kaidi Chen , Xiao Cheng , Shuai Xue , Junyan Chen , Xu Zhang , Yuwei Qi , Rong Chen , Yan Zhang , Hangjie Wang , Wei Li , Guilin Cheng , Ye Huang , Yang Xiong , Liping Chen , Chaofeng Mu , Mancang Gu

相关产品：indocyanine green（吲哚菁绿）

原文摘要：

Pancreatic cancer (PC) has a poor prognosis due to chemotherapy resistance and unfavorable drug transportation. Albumin conjugates are commonly used as drug carriers to overcome these obstacles. However, membrane-bound glycoprotein mucin 4 (MUC4) has emerged as a promising biomarker among the genetic mutations affecting albumin conjugates therapeutic window. Human serum albumin-conjugated arsenic trioxide (HSA-ATO) has shown potential in treating solid tumors but is limited in PC therapy due to unclear targets and mechanisms. This study investigated the transport mechanisms and therapeutic efficacy of HSA-ATO in PC cells with different MUC4 mutation statuses. Results revealed improved penetration of ATO into PC tumors through conjugated with HSA. However, MUC4 mutation significantly affected treatment sensitivity and HSA-ATO uptake both in vitro and in vivo. Mutant MUC4 cells exhibited over ten times higher IC50 for HSA-ATO and approximately half the uptake compared to wildtype cells. Further research demonstrated that ALPL activation by HSA-ATO enhanced transcytosis in wildtype MUC4 PC cells but not in mutant MUC4 cells, leading to impaired uptake and weaker antitumor effects. Reprogramming the transport process holds potential for enhancing albumin conjugate efficacy in PC patients with different MUC4 mutation statuses, paving the way for stratified treatment using these delivery vehicles.  

indocyanine green:吲哚菁绿（Indocyanine Green，ICG）是一种三碳菁染料，它是一种近红外荧光染料，化学名称为2 - [(7 -异丙基- 2 -甲基- 3H -吲哚- 3 -亚基) -亚甲基] - 3,3 -二甲基- 1 -丙基- 1H -吲哚- 6 -磺酸盐。ICG 在近红外区域（700 - 900nm）有较强的吸收和发射荧光的特性。这个波段的光在生物组织中的穿透性较强，组织自发荧光干扰相对较少，这使得 ICG 在生物医学成像等领域有优势。ICG 能溶于水和甲醇等有机溶剂，一般以注射用的水溶液形式存在。它的水溶液呈墨绿色，在一定条件下比较稳定，但对光和热较为敏感，长时间光照或高温环境可能会导致其分解。基于indocyanine green的性能，介绍如下：

图：吲哚菁绿结构式

标记过程：

用缓冲溶液将 HSA-ATO 配制成合适浓度的溶液，将吲哚菁绿（ICG）也用缓冲溶液配制成适宜浓度的溶液。按照一定的摩尔比或者质量比，将配制好的 ICG 溶液缓慢加入到 HSA-ATO 溶液中，一般是在温和搅拌的条件下逐滴加入，以保证反应均匀进行。之后将反应体系置于合适的温度环境下进行反应，期间可以间断性地涡旋混匀，确保反应充分进行。

将反应结束后的混合溶液转移至合适截留分子量的透析袋中，扎紧袋口，放入大量的缓冲溶液中进行透析，通过透析作用，使未反应的小分子 ICG 等杂质扩散到透析外液中，而标记好的 HSA-ATO-ICG 产物保留在透析袋内，达到纯化目的。

结论：

该文献成功使用indocyanine green标记HSA-ATO。结果表明，通过与 HSA 结合，ATO 能够更好地渗透到 PC tumour中，HSA-ATO 激活 ALPL 会增强野生型 MUC4 PC 细胞的转胞吞作用，但不会增强突变型 MUC4 细胞的转胞吞作用，从而导致摄取受损和抗tumour作用减弱。indocyanine green展现出良好的标记性能。