Near-Infrared Fluorescence Imaging of EGFR-Overexpressing Tumors in the Mouse Xenograft Model Using scFv-IRDye800CW and Cetuximab-IRDye800CW

Abstract

EGFR (epidermal growth factor receptor) is overexpressed in a variety of human cancers (including squamous cell carcinoma of head and neck, colon cancer, and some breast cancers) and therefore is regarded as an ideal target for cancer therapy or imaging purposes. In the current study, we produced a scFv-based near-infrared probe (called cet.Hum.scFv-IRDye-800CW) and evaluated its ability in recognizing and imaging of EGFR-overexpressing tumors in a mouse model. Like the molecular probe consisting of its parental antibody (cetuximab, an FDA-approved monoclonal antibody) and IRD800CW, cet.Hum.scFv-IRDye-800CW was able to recognize EGFR-overexpressing tumors in mice. cet.Hum.scFv-IRDye-800CW was found to be superior to the cetuximab-based probe in imaging of mouse tumors. The tumor-to-background ratio and blood clearance rate were higher when cet.Hum.scFv-IRDye-800CW was used as an imaging probe.

Tumour induction in BALB/c mice for imaging studies: An improved protocol

“…Since 1978, CsA has been frequently used both clinically and experimentally 4 . Many clinical researchers reported tumour xenograft development by modifying the CsA dose, administration route, combination with another drug and duration of treatment regimens 5–9 . CsA is metabolized in the liver by cytochrome P450.…”

“… 4 Many clinical researchers reported tumour xenograft development by modifying the CsA dose, administration route, combination with another drug and duration of treatment regimens. 5 , 6 , 7 , 8 , 9 CsA is metabolized in the liver by cytochrome P450. CsA metabolism can be decelerated by cytochrome inhibitors like diltiazem or ketoconazole.…”

“…In our previous work, we induced tumours of A‐431, U‐87‐MG human cancer cell tumours in BALB/c mice, 9 using the combination of CsA, ketoconazole and cyclophosphamide. In the current study, we describe the improved protocol in detail.…”

“…10 The risk for opportunistic invasive fungal infections is decreased when CsA and ketoconazole are combined. 11 In our previous work, we induced tumours of A-431, U-87-MG human cancer cell tumours in BALB/c mice, 9 using the combination of CsA, ketoconazole and cyclophosphamide. In the current study, we describe the improved protocol in detail.…”