Metildi Cristina A, Felsen Csilla N, Savariar Elamprakash N, Nguyen Quyen T, Kaushal Sharmeela, Hoffman Robert M, Tsien Roger Y, Bouvet Michael
Department of Surgery, University of California San Diego, San Diego, CA, USA.
Ann Surg Oncol. 2015;22(6):2082-7. doi: 10.1245/s10434-014-4144-1. Epub 2014 Oct 16.
The aim of this study was to evaluate the efficacy of using matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9)-cleavable ratiometric activatable cell-penetrating peptides (RACPPs) conjugated to Cy5 and Cy7 fluorophores to accurately label pancreatic cancer for fluorescence-guided surgery (FGS) in an orthotopic mouse model.
Orthotopic mouse models were established using MiaPaCa-2-GFP human pancreatic cancer cells. Two weeks after implantation, tumor-bearing mice were randomized to conventional white light reflectance (WLR) surgery or FGS. FGS was performed at far-red and infrared wavelengths with a customized fluorescence-dissecting microscope 2 h after injection of MMP-2 and MMP-9-cleavable RACPPs. Green fluorescence imaging of the GFP-labeled cancer cells was used to assess the effectiveness of surgical resection and monitor recurrence. At 8 weeks, mice were sacrificed to evaluate tumor burden and metastases.
Mice in the WLR group had larger primary tumors than mice in the FGS group at termination [1.72 g ± standard error (SE) 0.58 vs. 0.25 g ± SE 0.14; respectively, p = 0.026). Mean disease-free survival was significantly lengthened from 5.33 weeks in the WLR group to 7.38 weeks in the FGS group (p = 0.02). Recurrence rates were lower in the FGS group than in the WLR group (38 vs. 73 %; p = 0.049). This translated into lower local and distant recurrence rates for FGS compared to WLR (31 vs. 67 for local recurrence, respectively, and 25 vs. 60 % for distant recurrence, respectively). Metastatic tumor burden was significantly greater in the WLR group than in the FGS group (96.92 mm(2) ± SE 52.03 vs. 2.20 mm(2) ± SE 1.43; respectively, χ (2) = 5.455; p = 0.02).
RACPPs can accurately and effectively label pancreatic cancer for effective FGS, resulting in better postresection outcomes than for WLR surgery.
本研究旨在评估与Cy5和Cy7荧光团偶联的基质金属蛋白酶-2（MMP-2）和基质金属蛋白酶-9（MMP-9）可切割的比率激活细胞穿透肽（RACPPs）在原位小鼠模型中对胰腺癌进行准确标记以用于荧光引导手术（FGS）的疗效。
使用MiaPaCa-2-GFP人胰腺癌细胞建立原位小鼠模型。植入后两周，将荷瘤小鼠随机分为传统白光反射（WLR）手术组或FGS组。在注射MMP-2和MMP-9可切割的RACPPs后2小时，使用定制的荧光解剖显微镜在远红光和红外波长下进行FGS。利用GFP标记癌细胞的绿色荧光成像评估手术切除的有效性并监测复发情况。8周时，处死小鼠以评估肿瘤负荷和转移情况。
在实验结束时，WLR组小鼠的原发性肿瘤比FGS组小鼠的更大[1.72 g±标准误（SE）0.58 vs. 0.25 g±SE 0.14；p = 0.026]。平均无病生存期从WLR组的5.33周显著延长至FGS组的7.38周（p = 0.02）。FGS组的复发率低于WLR组（38%对73%；p = 0.049）。这导致FGS组的局部和远处复发率均低于WLR组（局部复发分别为31%对67%，远处复发分别为25%对60%）。WLR组的转移瘤负荷显著大于FGS组（96.92 mm²±SE 52.03对2.20 mm²±SE 1.43；χ² = 5.455；p = 0.02）。
RACPPs能够准确有效地标记胰腺癌以进行有效的FGS，与WLR手术相比，术后效果更佳。
