Detection of Esophageal Squamous Cell Carcinoma by Cathepsin B Activity in Nude Mice

Abstract

Background and ObjectiveDespite great progress in treatment, the prognosis for patients with esophageal squamous cell carcinoma (ESCC) remains poor, highlighting the importance of early detection. Although upper endoscopy can be used for the screening of esophagus, it has limited sensitivity for early stage disease. Thus, development of new diagnosis approach to improve diagnostic capabilities for early detection of ESCC is an important need. The aim of this study was to assess the feasibility of using cathepsin B (CB) as a novel imaging target for the detection of human ESCC by near-infrared optical imaging in nude mice.MethodsInitially, we examined specimens from normal human esophageal tissue, intraepithelial neoplasia lesions, tumor in situ, ESCC and two cell lines including one human ESCC cell line (Eca-109) and one normal human esophageal epithelial cell line (HET-1A) for CB expression by immunohistochemistry and western blot, respectively. Next, the ability of a novel CB activatable near-infrared fluorescence (NIRF) probe detecting CB activity presented in Eca-109 cells was confirmed by immunocytochemistry. We also performed in vivo imaging of tumor bearing mice injected with the CB probe and ex vivo imaging of resected tumor xenografts and visceral organs using a living imaging system. Finally, the sources of fluorescence signals in tumor tissue and CB expression in visceral organs were identified by histology.ResultsCB was absent in normal human esophageal mucosa, but it was overexpressed in ESCC and its precursor lesions. The novel probe for CB activity specifically detected ESCC xenografts in vivo and in vitro.ConclusionsCB was highly upregulated in human ESCC and its precursor lesions. The elevated CB expression in ESCC allowed in vivo and in vitro detection of ESCC xenografts in nude mice. Our results support the usefulness of CB activity as a potential imaging target for the detection of human ESCC.

Clinical significance of serum cathepsin B and cystatin C levels and their ratio in the prognosis of patients with esophageal cancer

“… 22 Moreover, CTSB was highly upregulated in human esophageal squamous cell carcinoma (ESCC), suggesting it plays a key role in the regulation of ESCC initiation and progression. 23 , 24 In the present study, we observed a significant increase of CTSB levels in the sera of patients with esophageal cancer compared with that of the healthy controls. Furthermore, CTSB levels were positively correlated with increasing tumor invasion depth, which is consistent with the findings listed earlier.…”

“…Tan et al showed that the serum level of CTSB was considerably higher in nasopharyngeal carcinoma patients than in controls and was correlated with the TNM score 22. Moreover, CTSB was highly upregulated in human esophageal squamous cell carcinoma (ESCC), suggesting it plays a key role in the regulation of ESCC initiation and progression 23,24. In the present study, we observed a significant increase of CTSB levels in the sera of patients with esophageal cancer compared with that of the healthy controls.…”

Cathepsins in digestive cancers

“…Cathepsin B is a potential target for detecting esophageal cancer [ 60 ] because it is expressed at low levels in the normal esophageal mucosa but is significantly overexpressed in esophageal cancer [ 61 ]. Habibollahi et al used white-light upper endoscopy combined with near-infrared imaging to detect cathepsin B and thereby screen for esophageal adenocarcinoma [ 62 ].…”

A microRNA-based liquid biopsy signature for the early detection of esophageal squamous cell carcinoma: a retrospective, prospective and multicenter study

“…Herein, we established a novel, noninvasive, miRNA-based signature using a systematic and comprehensive effort and by integrating transcriptomewide biomarker discovery and clinical validations using 7 independent, retrospective and prospective, multinational, multicenter cohorts. Our 8-miRNA signature demonstrated considerable clinical value for the noninvasive detection of early stage ESCC patients, remarkably superior to conventional tumor biomarkers for ESCC [17]. Application of our circulating, epigenetic signature as a non-invasive, inexpensive and facile diagnostic assay for ESCC could improve the mortality of patients with ESCC, long considered one of the deadliest malignancies.…”