Department of Thoracic Surgery, University of Pennsylvania, Philadelphia, Pennsylvania.
Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
Ann Thorac Surg. 2023 Sep;116(3):631-641. doi: 10.1016/j.athoracsur.2022.05.019. Epub 2022 May 27.
Intraoperative molecular imaging has emerged as a potential tool in addressing challenges faced during lung cancer surgery by localizing small lesions, ensuring negative margins, and identifying synchronous cancers. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) glycoprotein has emerged as a potential target in fluorescent labeling of non-small cell lung cancer given the high antigen density in tumor cells and absence of expression in normal parenchyma. The goal of our study was to determine whether anti-CEACAM5 targeted near-infrared fluorochrome could be a suitable target in non-small cell lung cancer.
The CEACAM5 expression was evaluated in AB-12 (known negative control), HT29 (known positive control), and H460 (non-small cell lung cancer) cell lines by polymerase chain reaction. SGM-101, a CEACAM5 antibody, coupled with a BM-104 near-infrared fluorescent tracer was evaluated with dose escalation, in vitro cellular localization, and immunofluorescence microscopy. Subsequently, in vivo validation was performed in 52 athymic nude xenografts.
Polymerase chain reaction analysis demonstrated 3000x relative expression of CEACAM5 in HT-29 cells compared with AB-12. The H460 cells showed 1000x relative expression compared with AB12 (P < .05). Both HT29 and H460 cells showed tracer internalization with signal to background ratio of 4.5 (SD 0.34) whereas there was minimal uptake by AB12 cells with signal to background ratio 1.1 (SD 0.1; P < .05). There was linear fluorescence increase with increasing tracer dosing in receptor expressing cell lines. In preclinical models, HT-29 and H460 cells lines produced near-infrared fluorescence with average tumor to background ratio of 3.89 (SD 0.25) irrespective of tumor size compared with no fluorescence by AB12 tumors (P < .05). The CEACAM5 expressing tumors had excellent dye uptake compared with AB12 tumors.
CEACAM5 serves as a possible receptor for targeted intraoperative molecular imaging resections in lung cancer. This study sets a path for evaluation of CEACAM5 targets in future clinical trials.
术中分子成像已成为解决肺癌手术中面临的挑战的潜在工具，通过定位小病变、确保阴性切缘和识别同步癌。癌胚抗原相关细胞粘附分子 5（CEACAM5）糖蛋白作为一种潜在的靶点，在非小细胞肺癌的荧光标记中具有较高的肿瘤细胞抗原密度和正常实质中无表达的特点。我们的研究目的是确定抗 CEACAM5 靶向近红外荧光染料是否可作为非小细胞肺癌的合适靶点。
通过聚合酶链反应评估 AB-12（已知阴性对照）、HT29（已知阳性对照）和 H460（非小细胞肺癌）细胞系中的 CEACAM5 表达。SGM-101，一种 CEACAM5 抗体，与 BM-104 近红外荧光示踪剂偶联，进行剂量递增、体外细胞定位和免疫荧光显微镜评估。随后，在 52 例裸鼠异种移植瘤中进行体内验证。
聚合酶链反应分析显示，与 AB-12 相比，HT-29 细胞中 CEACAM5 的相对表达为 3000x。H460 细胞的相对表达为 1000x 与 AB12 相比（P<.05）。HT29 和 H460 细胞均显示示踪剂内化，信号与背景比为 4.5（SD 0.34），而 AB12 细胞的摄取信号与背景比为 1.1（SD 0.1；P<.05）。在受体表达细胞系中，随着示踪剂剂量的增加，荧光呈线性增加。在临床前模型中，HT-29 和 H460 细胞系产生近红外荧光，平均肿瘤与背景比为 3.89（SD 0.25），与 AB12 肿瘤无荧光（P<.05）。CEACAM5 表达的肿瘤与 AB12 肿瘤相比，染料摄取良好。
CEACAM5 可作为肺癌术中靶向分子成像切除的潜在受体。本研究为未来临床试验中 CEACAM5 靶标的评估奠定了基础。
